Foreword — page 7
1. EXPERIMENTAL STUDIES OF NANOPARTICLES, NANOSYSTEMS, AND NANOMATERIALS — page 8
Anufriev I.E., Muratova E.N., Korolev D.V., Shulmeister G.A., Valeev R.G., Moshnikov V.A.
Development of a manual extruder for liposome homogenization — page 8
Abstract: Medications using liposomes are of great interest in pharmaceuticals. They increase the therapeutic index of the drug by enclosing the medicinal substance inside a biocompatible lipid envelope, which releases the solution only in the required area. Such drugs have already shown their effectiveness in the treatment of diseases related to oncology, dermatology, neurology, surgery, etc. To use liposomes for these purposes, it is necessary that their size be in the range from 50 to 200 nm. There are several ways to create vesicles of this size, but mostly they use either ultrasound exposure to a liposome solution or extrusion. The extrusion method is a method that allows to obtain the most homogeneous solution from liposomal particles. For extrusion, a special device – an extruder is required. It is a system that passes a liposomal solution under pressure through a filter with a certain pore size. In this paper, the process of liposome extrusion, types of liposomal extruders are considered and their pros and cons are evaluated, a model of a manual extruder capable of homogenizing up to 20 ml of solution was also developed. Different materials were considered and used for the construction of this device. The inspection of the extruder showed its operability and showed the advantages of using extrusion compared to the ultrasound exposure method.
Keywords: extrusion, liposomes, homogenization, membrane, porous aluminum oxide, extruder, 3D modeling.
Apekov A.M., Shebzukhova I.G.
Orientational dependence of the interphase energy of low-temperature modification of titanium at the boundary with an organic liquid — page 17
Abstract: Calculations of the interphase energy of low-temperature modification of titanium at the boundary with nonpolar organic liquids are carried out within the framework of the electron-statistical method, corrections to the interphase energy for the dispersion interaction of Wigner-Seitz cells and the electron density oscillation in the transition layer, the polarization of surface metal ions and organic liquid in the field of a semi-infinite metal are obtained. When calculating the interphase energy, changes in all components of the metal bond energy in the transition layer are considered – the eigenenergies of the electron gas, the energies of the interaction of the electron gas with ions. The effect of an organic liquid on the orientational dependence of the interphase energy of alpha-titanium and the corrections to the interphase energy taking into account the permittivity of the organic liquid is established. It is shown that the dispersion and oscillation corrections increase the interphase energy, and the polarization correction reduces the interphase energy. A sharp anisotropy of the interphase energy and corrections is obtained for this titanium structure.
Keywords: interfacial energy, polarization correction, dispersion correction, electron-statistical method, non-polar organic liquid, titanium.
Barbin N.M., Yakupova L.V., Terent’ev D.I., Kuanyshev V.T.
Decomposition of fullerene C28 in a nitrogen atmosphere — page 24
Abstract: A study of the behavior of С28 fullerene when heated in a nitrogen atmosphere was conducted. The calculations were made using the thermodynamic modeling method, which consists in a complete thermodynamic analysis of the system using the TERRA software complex. The range of minimum and maximum heating temperatures was 273-3373 K and pressure was 0,1 MPa. A graph of the carbon balance in the С28 – N2 system was built, chemical reactions were determined, temperature intervals were allocated for each reaction. Temperature intervals of the thermal stability of carbon nanoparticles in the condensed and vapor phases are established. In the gas phase, С28 steam shows increased thermodynamic stability and only reacts with vapors at high temperatures, as evidenced by a sharp decrease in its content. The equilibrium constants of the reactions are calculated, and graphs of the dependence of the equilibrium constants of the reactions on temperature are given. For each reaction, the calculated data were approximated by the linear dependence.
Keywords: fullerenes, carbon nanoparticles, thermodynamic modeling, physical and chemical process.
Bernatskii D.P., Pavlov V.G.
The effect of the interaction of barium atoms on the surface of the rhenium field emitter on the work function — page 31
Abstract: Modification of the emission surface on a nanometer scale during adsorption of barium atoms on the surface of a rhenium field emitter was investigated using field electron and desorption microscopy. Field electronic images of the emitter surface reflecting the localization of barium atoms on the emitter surface, representing the quasi-spherical surface of a rhenium single crystal, were obtained. The influence of the temperature of the emitter with adsorbed barium on the change in the emitter work function is shown. Deposition at room temperature leads to the appearance of a dependence of the work function on the concentration of adsorbate with a minimum in the area of optimal coating. Annealing of the emitter at T = 600 K after deposition of each portion of barium causes the minimum to disappear. After reaching the minimum value (optimal coverage with adsorbed atoms), the work function remains constant with an increase in the number of adsorbed barium atoms on the surface of the emitter. A sharp change in the localization of barium atoms due to a phase transition with the formation of islands in the region of the rhenium face was detected on the field electronic image. The change in the nature of the dependence of the work function is associated with a phase transition in the barium film with the formation of barium islands. The concentration of barium in the islet is constant and corresponds to the optimal coating.
Keywords: field emitters, field electron and desorption microscope, adsorption, rhenium, barium.
Blinov A.V., Shevchenko I.M., Pirogov M.A., Gvozdenko A.A., Golik A.B., Leontev P.S.
Investigation of the effect of the molar ratio of reagents on the dimensional and structural characteristics of cobalt hexacyanoferrate nanoparticles — page 39
Abstract: In this work the influence of the molar ratio on the dimensional and structural characteristics of cobalt hexacyanoferrate nanoparticles was studied. The synthesis was carried out by chemical method in an aqueous medium using potassium hexacyanoferrate and cobalt nitrate. As a result of the study of samples by the method of dynamic light scattering, the values of the hydrodynamic radius of the samples were obtained. It was found that the minimum size (R = 76 nm) has a sample with a molar ratio K3[Fe(CN)6] : Co(NO3)2= 4 : 1. Scanning electron microscopy revealed that cobalt hexacyanoferrate samples are irregularly shaped aggregates consisting of nanoparticles with a diameter of 50 to 150 nm. As a result of X-ray phase analysis, it was found that the samples have a face-centered cubic crystal structure (Fm 3 m). According to the Debye-Scherrer equation, the average size of crystallites in the samples is from 17 to 20 nm.
Keywords: transition metal hexacyanoferrates, cobalt hexacyanoferrate, cobalt nitrate, scanning electron microscopy, dynamic light scattering, powder diffractometry, hydrodynamic radius.
Bolshakova N.N., Druginina N.Yu., Ivanova A.I., Pavlova D.N., Ped`ko B.B., Semenova E.M.
Repolarization properties of copper-containing crystals of triglycine sulfate — page 50
Abstract: The paper presents the results of the analysis of experimental dielectric hysteresis loops and field dependens of polarization switching of initial and annealed crystals of triglycine sulfate, doped copper (the concentration range (4,2–8,7) 10-3 wt.%). It has been experimentally established that their dielectric hysteresis loops do not have distortions. It has been found that the relative and effective permittivities and switchable polarization increase with increasing impurity concentration in crystals of TGS:Cu2+. The field dependences of the effective permittivity have extrema: before annealing the samples, the maxima of the εeff(E) curves correspond to a field value of about (20-40)∙103 V∙m-1, and for annealed samples these fields have a value of ~(15-30)∙103V∙m–1. Annealing of the samples increases the mobility of domain walls, which promotes the transformation of lenticular nuclei of domains into lamellae.
Keywords: triglycine sulfate, repolarization, domain structure, switching processes, hysteresis, permittivity.
Golovanova O.A.
Study of calcium oxalate nanocrystalline structures and kinetics of calcium oxalate deposition — page 61
Abstract: Calcium oxalates, represented by wavellite CaC2O4·H2O and weddellite CaC2O4·2H2O (the most stable forms), are the main components of stones in the genitourinary system, and are also part of dental, gallstones, and other mineral deposits. It is known that modern approaches to the study and modeling of crystallization processes make it possible to analyze the influence of a number of factors (exogenous and endogenous) arising at various levels of organization: from atoms and molecules to macroscopic processes occurring in industrial devices. The process of crystallization, taking into account the variety of acting factors and forms of crystal structures, consists of two main stages: formation of a solid phase nucleus and its growth (formation of a solute crystal). In this work, using modern approaches, the physicochemical and kinetic patterns of crystallization of calcium oxalates under conditions close to physiological are determined. The effect of physiological solution components (organic and inorganic) was studied, the staged mechanism of the solid phase formation was established, and the kinetic parameters of the growth stage were calculated (lgk = 33.1). The inhibitory effect of inorganic additives (Mg2+, Cl–), amino acids (glycine, glutamine, aspartic) and the accelerating effect of hydroxyapatite crystals, seed in the form of calcium oxalate and urea crystals on the crystallization process were revealed.
Keywords: .
Golovanova O.A.
Crystallization of nanocrystalline hydroxylapatite in the presence of albumin — page 71
Abstract: Due to the development of modern biotechnologies and nanomaterials, in the near future it is expected to achieve a new, higher quality level in the design and improvement of the characteristics of intraosseous implants used in orthopedics. Calcium phosphate was synthesized from a model solution of synovia in the presence of albumin. Synthetic solid phases were studied using X-ray phase analysis, IR-Fourier spectroscopy, scanning electron microscopy, and energy dispersive analysis. The supernatant was examined for the presence of ions and to calculate the ratio. It was found that albumin does not affect the phase composition of the samples: the sediments are single-phase and consist of B-type hydroxylapatite carbonate. The study of the structure and morphology of the solid phase showed that the presence of proteins leads to formation of composites with a lower specific surface area compared to hydroxylapatite carbonate. The largest crystallite size is observed for the hydroxylapatite carbonate /albumin sample with the albumin concentration of 12 g/l. With the help of the thermal analysis of the fixation of thermal effects five stages of the thermal transformation were identified in the temperature range of 25-1000 °C; for all samples, the main stages are II–III, associated with the thermal destruction of organic additives. The study of the bioactivity of the samples showed that in the case of active resorption, the most soluble were the samples synthesized in the presence of albumin (>7 g/l), and in the case of passive resorption, the hydroxylapatite carbonate/albumin samples (5 and 7 g/l).
Keywords: crystallization, hydroxylapatite, albumin, adsorption, bioresorbability.
Gudkov S.I., Solnyshkin A.V., Zhukov R.N., Kiselev D.A.
Electrical response of lithium niobate and lithium tantalate thin films to modulated thermal radiation — page 82
Abstract: In this work, we studied the pyroelectric activity of thin polycrystalline lithium niobate films fabricated by radio frequency magnetron sputtering and laser ablation, and thin polycrystalline lithium tantalate films fabricated by radio frequency magnetron sputtering. Using the dynamic method of studying the pyroelectric effect, it was found that all samples have self-polarization that occurs during the post-growth thermal annealing of the structure. An estimate of the pyroelectric coefficient showed that the values of the pyroelectric coefficient of lithium niobate and lithium tantalate thin films are several times lower than the values of the pyroelectric coefficient for bulk crystals of the corresponding materials. This may be due to the fact that the polarization vector of some grains lies in the film plane, as well as to the traps existing in the film volume and at the film/substrate interface, on which charge carriers recombine and do not participate in the generation of the pyroelectric current.
Keywords: lithium niobate, lithium tantalate, thin film, dynamic method, self-polarization, pyroelectric effect, pyroelectric coefficient, LiNbO3, LiTaO3, ferroelectric, laser ablation method, radio frequency magnetron sputtering.
Zernitsa D.A.
Crystallization of lead-free binary tin-zinc alloys produced by the method of rapidly solidification from the melt — page 92
Abstract: The results of studies of the structures of rapidly solidified foils of alloys of the Sn – Zn system with a low content of alloying elements (up to ~1,5 wt.%), alloys of near-eutectic compositions, as well as alloys with an alloying element content of 20 – 95 wt.% are presented. In rapidly solidified alloys containing 1,5 wt. % Sn and 1,2 wt. % Zn, supersaturated solid solutions are formed, which decompose according to the mechanism of formation and growth of nuclei of a new phase at room temperature. Alloys (4,4 – 15 wt.% Zn) after rapidly solidification are supercooled and supersaturated with both components, and experience spinodal decomposition followed by the formation of supersaturated solid solutions based on Sn and Zn, which decompose at room temperature. In all other alloys, a two-phase structure is formed from solid solutions based on Sn and Zn. It was found that as the crystallization front moves from the surface of the contacting foil layer with the surface of the mold, the Sn particles coarsen and the specific surface of the interface
decreases. It has been established that rapidly solidified foils have a microcrystalline grain structure, with an increase in the concentration of alloying elements, a tendency to a decrease in grain size is observed.
Keywords: rapidly solidified alloys, zinc, tin, grain, spinodal decomposition, supersaturated solution, eutectic, structure.
Zigert A.D., Semenova E.M., Kuz`min N.B., Sdobnyakov N.Yu.
Fractal analysis of magneto-optical images of a magnet surface after exposure to a pulsed field — page 101
Abstract: The results of fractal analysis of images of the surface of a permanent magnet KS37 obtained by the method of the polar Kerr effect using an indicator bismuth-containing ferrite-garnet film after magnetization reversal by a pulsed field of 0,1 – 1,5 T are presented. The obtained dependences of the remanent magnetization on the magnitude of the external pulsed field are compared with the fractal dimension of the magneto-optical images of the magnet surface after exposure to the pulsed field. It is hypothesized that the field dependences of the fractal dimension of the profile of magneto-optical images of the magnet surface coincide in shape with the graphs of the first derivative dMr(H)/dH of the magnetization with respect to the field, i.e. there is a relationship between the nature of the magnetization change in a pulsed field and the type of the magneto-optical image analyzed by using the fractal geometry methods.
Keywords: permanent magnet, effect, ferrite-garnet films, domain structure, fractal dimension, derivative of magnetization with respect to magnetic field.
Ivanov D.V., Antonov A.S., Semenova E.M., Ivanova A.I., Kuz`min N.B., Sdobnyakov N.Yu.
On the formation of fractal iron films — page 108
Abstract: The patterns of formation of the fractal relief of nanosized iron films on the mica surface are considered using the atomic force microscopy. In order to prevent the formation of an oxide layer, iron films were studied immediately after their production employing at a magnetron sputtering unit. It has been established that magnetron sputtering makes it possible to obtain island films of iron, the structural element of which are truncated nanocubes – nanopyramids. The fractal dimension of the resulting agglomerates was determined at various scales: on a scale of 5 µm Dc = 2,462±0,113; on a scale of 3 µm Dc = 2,373±0,122; on a scale of 1 µm Dc = 2,298±0,139. The distribution of the probability of detecting agglomerates on the films under study with a certain fractal dimension of the surface of iron films is estimated. The subsequent elemental analysis of the iron films showed the presence of oxygen and, consequently, the formation of ordered oxide films of the core-shell type.
Keywords: atomic force microscopy, magnetron sputtering, fractal dimension, iron films, nanopyramids.
Ivanova A.I., Svesnikov P.A., Marinicheva K.A., Gugutsidze K.A., Vasilev A.D., Tretiakov S.A., Karpenkov A.Yu.
Comparative studies of the strength properties of germanum and silicon single crystals — page 120
Abstract: In this paper, we present the results of microhardness tests performed by Vickers indentation of germanium and silicon single crystals. It’s shown that in the investigated samples there is a dependence of microhardness on the crystallographic directions and the nature of the alloying impurity. Microhardness anisotropy coefficients are calculated: for germanium KII=1,2 and for silicon KII=1,3. The analysis of high-temperature annealing influence on microhardness value of germanium and silicon crystals is carried out. It has been established, that the microhardness of Ge(111) crystals grows on 12% after annealing at 550°С, the further thermal processing of germanium crystals at T=650°С considerably changes the structure and surface relief which contribute to a decrease in microhardness values. It is shown that the microhardness of silicon crystals increases by 10% after annealing at 750°C, further annealing to T=850°C leads to a decrease in microhardness. The surfaces of single crystals after high-temperature annealing have been studied; it has been established that thermal treatment at T≈0.6 Tm (Tm – the melting temperature of the single crystal) leads to the appearance of defects and a tenfold increase in the maximum height of the surface profile (from 10-12 nm to 100-200 nm).
Keywords: germanium and silicon single crystals, microhardness, Vickers method, microhardness anisotropy coefficient, interatomic bonds, dopants, high-temperature annealing, surface nanorelief, defects.
Ivanova A.I., Musabirov I.I., Semenova E.M., Vasilev A.D., Gugutsidze K.A., Karpenkov A.Yu.
Influence of deformation on the microsructure and magneic properties of Heusler alloys — page 132
Abstract: This paper presents the results of studies of the effects of deformation obtained by the method of multiple isothermal forging on the microstructure and magnetic properties of the NiMnGa alloy system. It is shown that the microstructure of the initial alloy during deformation undergoes changes, grain size decreases and a two-component structure is formed. The magnetic domain structure of the original and deformed alloys was visualized by magnetic force microscopy. It is shown that the distortion of the domain shape is associated with the presence of a martensitic relief and grain boundaries, 180-degree magnetic domains are continuous within the crystallites, while they cross the flat parallel boundaries of the martensite plates. The study of temperature and field magnetization dependences of the initial and isothermal forging samples demonstrates an insignificant magnetization decrease and a shift of the phase transition temperature toward low temperatures. It’s concluded that deformation by the isothermal forging method can be considered as a way to correct the phase transition temperature in NiMnGa alloys with preservation of magnetization.
Keywords: Heusler alloys, martensitic relief, multiple isothermal forging, micro and nanostructure, magnetic domain structure, magnetostructural transition.
Karmokova R.Yu., Karmokov A.M., Molokanov O.A., Khasanov A.I., Kanametov A.A.
Influence of the parameters of acoustic waves on the characteristics of cavitation bubbles in liquid aluminum — page 141
Abstract: Calculation of parameters of a cavitation bubble during irradiation of aluminum melt with acoustic waves is carried out. The dependences of the Mach number on the amplitude at frequencies of 1-20 kHz used in the experiments are obtained. A relationship has been established between the resonant frequency of acoustic waves and the size of cavitation bubbles in liquid aluminum. Allowing the possibility of generalizing the Minnert linear theory to the case of viscous liquids, the dependence of the maximum radius of cavitation bubbles on the frequency of the acoustic field at different temperatures is obtained, taking into account the surface tension, density and viscosity of liquid aluminum. It has been established that with an increase in the frequency of the acoustic field, the radii of the cavitation bubbles decrease. The temperature change inside the cavitation bubble is estimated as a function of the bubble radius at any moment of its compression under adiabatic conditions. It is shown that when the bubble radius decreases to a critical size, the temperature inside it can increase by an order of magnitude.
Keywords: aluminum, acoustic waves, cavitation, cavitation bubble, Mach number.
Karpenkov A.Yu., Rakunov P.A., Musabirov I.I., Dunaeva G.G.
Influence of deformation processing on magnetocaloric effect of Heusler alloys — page 149
Abstract: This paper presents the results of complex studies of the effect of deformation obtained by the multiple isothermal forging method on the magnetocaloric properties of the Ni-Mn-Ga Heusler alloy system. Direct measurements of the adiabatic temperature change show that cycling the sample in a magnetic field μ0ΔH=1,85 T can decrease the maximum of ΔTad(T)0→H by the value corresponding to the latent heat of transition. Neglecting this transformation effect leads to an overestimation of the magnetocaloric effect of materials with the first-order transition. An analysis of the deformation treatment effect on the phase transformation temperatures and the magnitude of the magnetocaloric effect indicates that the application of multiple isothermal forging leads to a small decrease of the magnetization and the magnitude of the magnetocaloric effect. Deformation also causes a shift in the phase transition temperature towards low temperatures and decrease of the temperature hysteresis width.
Keywords: Heusler alloys, multiple isothermal forging, magnetocaloric effect, magnetostructural phase transition.
Kul’kov V.G., Kul’kova V.V.
Internal friction caused by migration of the intercrystalline boundary in the metal — page 159
Abstract: The model of internal friction at the migrating intercrystalline boundary is considered. Under the action of an alternating external stress oriented normally to the boundary, compression and stretching of the mating crystallites occurs. Due to their anisotropy and mutual reversal, Young’s modules in the direction of the stress action are different. The volume density of elastic energy in crystallites is different. This leads to the emergence of an effective driving force for boundary migration. As a model, a square segment of the boundary is selected, fixed along the perimeter by triple grain joints. The Laplace stress from the side of the curved boundary is counteracting. The differential equation of the connection of the boundary displacement with the total voltage is solved by the Fourier method. Based on this solution, the internal friction is calculated. The relaxation time spectrum consists of a series of lines. Each of them corresponds to the peak of Debye. The main peak has a significant value, smaller peaks are superimposed on it. The resulting maximum of internal friction widens in comparison with the Debye peak.
Keywords: driving force, migration of the intercrystalline boundary, peak of internal friction, relaxation time.
Lapin V.A., Kasyanov I.V.
The growth of InAlN/Si heterostructures with a high content of In — page 168
Abstract: InAlN films on Si (111) were obtained by the ion-beam deposition with various technological growth parameters. The results of the study of grown films by the scanning electron microscopy were used to identify the conditions for obtaining InAlN continuous films. Due to the mismatch of the lattice parameters of the film and substrate, the growth has an island character, a solid film was obtained only with the following technological parameters: the energy level of the beam U = 600 eV at the ion current of the beam ji = 32 mA, with the neutralization current of the beam jn = 32 mA, the substrate temperature of 400°C. With an increase of the nitrogen concentration to 80-90% in the gas mixture, a transition from an island to an epitaxial growth mechanism took place. The ratio of the elements In, Al and N in the film showed that the active plasma of the ion beam breaks down weakly bound ions and leaves only normally embedded nitrogen atoms N-3, but excessively strong exposure leads to metallization of the films.
Keywords: heteroepitaxy, InAlN, ion-beam deposition, elemental analysis, scanning electron microscopy, heterostructures.
Malashenko V.V., Malashenko T.I.
Effect of dislocation density on the dynamic yield strength of alloys with nanoscale defects under high energy external actions — page 176
Abstract: A theoretical analysis of inelastic processes in aged alloys under intense external influences is carried out. The analysis was carried out within the framework of the theory of dynamic interaction of defects. An analytical expression for the dependence of the dynamic yield strength on the dislocation density has been obtained. The reason for the different influence of nanostructural defects on the dislocation motion under high strain rate deformation and quasi-static deformation is determined. It is shown that under high strain rate deformation, nanosized defects affect the nature of the dependence of the dynamic yield strength on the dislocation density. This dependence becomes nonmonotonic and has a minimum. At the minimum point, there is a transition from the dominance of the drag of the dislocation by Guinier-Preston zones to the dominance of its drag by other dislocations. Numerical estimates of the contribution of the Guinier-Preston zones to the yield strength are made. It is shown that at a high concentration of Guinier-Preston zones, this contribution is very significant. Numerical estimates are made of the dislocation density at which the Taylor relation is violated.
Keywords: high-speed deformation, dislocations, Guinier-Preston zones, point defects, nanomaterials, Taylor ratio.
Malyshkina O.V., Ivanova A.I., Mamaev D.V.
The effect of tellurium vapor on the structure formation and dielectric properties of a multicomponent system based on sodium-potassium niobate — page 183
Abstract: The paper presents the results of studying the effect of paratellurite vapor during sintering on the dielectric properties of a multicomponent system based on sodium–potassium niobate ceramics (mKNN) with the general formula (Na0,5K0,49Li0,05Sr0,05)(Nb0,9Ta0,05Ti0,05)O3. The inclusion of paratellurite in mKNN ceramics changes the shape and increases the grain size by an order of magnitude. Thus, if grains containing only mKNN material have a cubic shape, then the presence of tellurium leads to the formation of grains in the form of sufficiently long tubes (when the length is several times greater than the diameter) with a porous internal structure. The addition of TeO2 to the mKNN composition leads to the disappearance of the maximum observed for mKNN on the temperature dependence of the permittivity in the region of 220-250°C, which corresponds to a nonferroelectric structural phase transition in KNN ceramics, and to smoothing the resonant- antiresonant peak in the range of 5-15 MHz, which appears in the KNN system with the introduction of modifiers.
Keywords: piezoelectric ceramics of potassium sodium niobate, lead-free materials, grain structure, complex permittivity dispersion.
Malyshkina O.V., Shishkov G.S., Ivanova A.I.
Structure and dielectric properties of a layered composite of barium titanate – barium ferrite — page 194
Abstract: The paper presents the results of a study of the influence of a constant magnetic field on the dispersion of the complex permittivity of a layered composite (connectivity 2-2) based on barium titanate – barium ferrite. It is shown that in the manufacture of a magnetoelectric composite of barium titanate – barium ferrite with a connectivity of 2-2, a strong diffusion of iron appears into the barium titanate ceramic layer at the interface between the two materials. It was found that iron penetrates evenly, with random deviations, and no exponential decline as iron enters into barium titanate is observed. It has been established that a constant magnetic field does not affect the dielectric characteristics in an alternating electric field at frequencies above 1600 Hz. At lower frequencies, annealing in the paraelectric phase increases the resistance of the sample, and subsequent exposure to a constant magnetic field leads to its decrease. It was revealed that changing the type of connectivity of the magnetoelectric composite from 0-3 to 2-2 adds additional, smaller, resonance and
antiresonance peaks in the study of piezoelectric properties by the resonance-antiresonance method. At the same time, the samples have sufficient values of the piezoelectric modulus for practical application (d31 > 40·10-12 C/N; d33 > 120·10-12 C/N).
Keywords: multiferroic, barium ferrite, barium titanate, magneto-electric composite, piezoelectric ceramic structure.
Maraeva E.V., Tokmeilova S., Sagitova D.R., Kononova I.E., Moshnikov V.A., Skornikova S.A.
Study on the microporous structure parameters of BEA type zeolites — page 203
Abstract: The paper considers a series of zeolite materials used as catalysts. Since the formation of mesoporosity in a microporous matrix is one of the methods for increasing the efficiency of zeolite materials in catalysis, it is necessary to control their porous structure parameters. The effect of post-synthetic treatment with acid and alkali solutions on the specific surface area of zeolites of the BEA type has been studied. The method of low-temperature (at 77 K) adsorption of nitrogen vapors was used to determine the external specific surface area (excluding micropores) and the volume of micropores in the samples on a Sorbi device. It has been shown that modification of BEA-type zeolite with concentrated mineral acids leads to both a decrease in the volume of micropores and a decrease in the specific surface area. At the same time, it was established by the X-ray phase analysis that the treatment with concentrated acids does not lead to destruction of the crystal structure of zeolites. In the case of treatment with alkali solutions, the specific surface area of the samples increases and the volume of micropores sharply decreases.
Keywords: zeolites, BEA type, hierarchy, mesopores, micropores, adsorption, specific surface area.
Nepsha N.I., Veselov A.D., Savina K.G., Bogdanov S.S., Kolosov A.Yu.., Myasnichenko V.S., Sdobnyakov N.Yu..
Variability of structural transformations in bimetallic Cu-Ag nanoalloys — page 211
Abstract: In this work, bimetallic Cu-Ag nanoparticles of five stoichiometric compositions of various sizes were studied by molecular dynamics method using a many body EAM potential. Regularities of the structure formation are established, their characteristic features are described. In particular, in compositions with 10, 70, and 90 at.% Cu content, after the melt cooling, typical fcc structures with intersecting atomic planes of the hcp phase are formed. In compositions of 30 and 50 at.% Cu, the fraction of identified phases does not exceed 20% of the total number of atoms. A tendency to the formation of a core-shell structure was revealed in the case of a high copper content, while in the case of a high silver content, a so-called onion structure is formed. Using the caloric curves of the potential term of the internal energy, the melting and crystallization temperatures were determined. It has been established that the concentration dependences of the melting temperature of bimetallic Cu-Ag nanoparticles have a minimum corresponding to the equiatomic composition for all sizes. For the crystallization temperature, both the concentration dependences and the size dependences are less pronounced, but the minimum value of the crystallization temperature also corresponds to the equiatomic composition for all sizes; with an increase in the size of bimetallic Cu-Ag nanoparticles, a slight increase in the crystallization temperature is observed.
Keywords: molecular dynamics method, LAMMPS, EAM potential, polyhedral template matching method, bimetallic nanoparticles, silver, copper, structure formation, melting and crystallization temperatures.
Sidorov N.V., Smirnov M.V., Titov R.A., Teplyakova N.A., Palatnikov M.N.
Optical properties of LiNbO3:B crystals — page 227
Abstract: The optical properties of nominally pure LiNbO3stoich, near-stoichiometric LiNbO3stoich (6,0 wt% K2O), LiNbO3cong and LiNbO3:B (0,55 and 0,83 mol% B2O3 in the charge) crystals in the visible region of the spectrum (λ = 380-700 nm) were studied by photoluminescence. LiNbO3:B crystals were grown by Czochralski using the technology of a direct solid-phase doping of the congruent charge by boron oxide (B2O3). The photoluminescence intensity increases in the series of crystals: LiNbO3stoich, LiNbO3stoich (6,0 wt% K2O), and LiNbO3cong. The photoluminescence intensity is determined by the concentration of deep electron traps (NbLi – «niobium antisite») and the stoichiometry of these crystals. The photoluminescence intensity of LiNbO3:B (0,55 and 0,83 mol% B2O3 in the charge) crystals is close to the photoluminescence intensity of LiNbO3stoich crystal. This can be explained by the fact that the composition and structure of LiNbO3:B (0,55 and 0,83 mol% B2O3 in the charge) crystals approach the composition and structure of the stoichiometric crystal.
Keywords: lithium niobate, crystal, defects, direct solid-phase doping, photoluminescence.
Sidorov N.V., Kadetova A.V., Titov R.A., Teplyakova N.A., Palatnikov M.N.
Specific features of the defect structure of LiNbO3:B crystals — page 235
Abstract: Specific features of the defect structure of nominally pure LiNbO3:B crystals were studied by the X-ray diffraction analysis. Nominally pure LiNbO3:B crystals were grown by Czochralski using the technology of the direct solid-phase doping of the congruent charge by orthoboric acid (H3BO3). The bonds lengths of Me-O in MeO6 clusters (Me-Li, Nb) determine the ferroelectric and nonlinear optical properties of the lithium niobate crystal. The values of these bonds in LiNbO3:B crystals differ significantly from the bonds lengths of the nominally pure congruent crystal LiNbO3cong. The differences in the bonds lengths are caused by a change in the properties of the boron-containing melt, technological parameters of the growth of LiNbO3:B crystals, and the localization of a trace amounts of boron in tetrahedral voids of the lithium niobate crystal structure. The results of the study of LiNbO3:B crystals were compared with those for nominally pure LiNbO3cong crystals and near-stoichiometric LiNbO3stoich (5,5 wt% K2O) ones.
Keywords: lithium niobate, crystal, defects, direct solid-phase doping, X-ray diffraction analysis.
Strechen A.S., Kurnosov Yu..A., Karpenkov A.Yu.., Ivanova A.I., Sinkevich A.I., Semenova E.M., Pastushenkov Yu..G.
Surface study of Tb0,16Ho0,84Fe2,00-xCox intermetallics — page 243
Abstract: The results of the study of the crystal structure, magnetic properties, as well as of micro-and domain structure of the surface of a series of compounds Tb0,16Ho0,84Fe2,00-xCox (x = 0,1; 0,2; 0,3; 0,4) are presented. It is shown that an increase in the relative content of cobalt leads to a decrease in the crystal lattice parameter a from 7,310 Å at x = 0,1 to 7,304Å at x = 0,4. At the same time, the Curie temperature increases accordingly from 581 to 614 K. It has been experimentally established that, as x increases, the specific saturation magnetization decreases linearly with increasing temperature. It has been found that the mechanical impact on the surface of sections during polishing can lead to the appearance of a regular microrelief. The results of studying the domain structure of the surface are presented. It is shown that the configuration and linear dimensions of the domains change as a result of the impact on the surface of the samples.
Keywords: intermetallics, Laves phase, magnetic properties, surface, microstructure, domain structure.
Elcheparova S.A., Kokoevа A.A.
Luminescent method for determination of nanoscale particles of rare earth elements with sulfosalicylic acid derivatives — page 254
Abstract: It was of interest to search for luminescent reactions to terbium in complexes with sulfosalicylic acid derivatives and to enhance them by studying the effect of third components (aminopolycarboxylic acids, organic bases and surfactants). As the results of the conducted studies have shown, surfactants increase the intensity of the glow of terbium ions in complexes with sulfosalicylic acid derivatives. The existence of a bright luminescent reaction of green terbium in complex with the methyl ester of S-(4-bromanilide) sulfosalicylic acid has been established. Optimal conditions for the complexation of terbium have been selected and highly sensitive luminescent methods for the determination of terbium in various objects have been developed. Terbium is converted into a luminescent complex compound with an organic reagent –
methyl ether S-(4-bromanilide) sulfosalicylic acid in the presence of a cationic surfactant decylpyridinium chloride in a ratio of 1: 2: 13, pH = 7,9 ± 0,08. The resulting complex compound of terbium, when irradiated with ultraviolet light from a mercury lamp, gives intense green luminescence, stable during standing and irradiation. The proposed method makes it possible to determine terbium in oxides of rare earth elements, which are luminescence quenchers with a sensitivity of 10-6 – 10-8%, bypassing the extraction stage.
Keywords: nanoscale particles, rare earth elements, lanthanides, organic reagent, complex compound, terbium, luminescence, detection limit.
2. THE THEORY OF NANOSYSTEMS — page 264
Anofriev V.A., Nizenko A.V., Ivanov D.V., Antonov A.S., Sdobnyakov N.Yu..
To the problem of automation of the process of determination of the fractal dimension — page 264
Abstract: In this paper, using various software products (Gwyddion, Mountains 9 DigitalSurf, Image Analysis P9) as well as our own program FractalSurface, we analyzed the possibilities of calculating the fractal dimension for various types of data using several numerical methods (cube counting method, triangulation method, variation method, as well as methods of the spectrum power, «scaling» analysis, morphological envelopes) and the possibilities for their working with the obtained values, such as: selecting a linear section of the graph for recalculating the final value of dimension, using matrix convolutional filters with different convolution kernels for image processing and of the batch analysis of the studied images. At the current time, there is no software product that would satisfy all the requirements for image analysis for the presence of self-affine structures, however, the availability of sufficient functionality mainly depends on the type of study. The comparative analysis of the obtained results allows us to evaluate the capabilities of the software product for further use as tools for automating the process of determining the fractal dimension and of the primary image processing.
Keywords: fractal dimension, cube counting method, triangulation method, variance method, power spectrum method, scaling analysis method, morphological envelopes method, image processing software.
Akhmatov Z.A., Akhmatov Z.A.
On the possibility of controlling the band gap in graphene — page 277
Abstract: Using first principles calculations, the possibility of controlling the electronic band structure of the single-layer graphene was investigated. It is shown that when potassium atoms are adsorbed on the graphene surface, an energy gap appears in its electronic spectrum. It was also observed that the band gap strongly depends on the number of adsorbed atoms, namely, with an increase in the number of adsorbed atoms, the band gap in graphene can either increase or disappear. For example, when there is one potassium atom per 32 carbon atoms in the graphene lattice, the band gap is ΔE = 0,1 eV. An increase in the number of potassium atoms to two leads to disappearance of the energy gap, while for three potassium atoms ΔE = 0,22 eV. It should also be noted that the appearance of a band gap during adsorption does not break the symmetry of the graphene sublattices. This observation seems interesting to us, since according to many authors, it is the break of the sublattices symmetry that is the main reason for the appearance of a band gap in graphene.
Keywords: graphene, electronic band structure, ab initio calculations, adsorption, alkali metal atoms.
Belyaeva I.N., Kirichenko I.K., Chekanova N.N.
Solving of some nonlinear ordinary differential equations in the form of power series — page 284
Abstract: In the current scientific literature, a variety of nonlinear ordinary differential equations are widely and successfully used to describe real processes in various fields of natural sciences: optics, elasticity theory, molecular physics, etc. For example, the Ermakov and Riccati equations are used to solve the quantum Schrodinger equation, in electrodynamics. However, unfortunately, there are no well-and reliably developed and generally accepted methods for solving nonlinear differential equations. In addition, most of the Riccati equations are not integrated even in quadratures. In this paper, to construct solutions to the nonlinear Ermakov and Riccati equations, it is proposed to use the corresponding so-called connected linear differential equations, the solutions of the latter are in the form of power series using modern computer systems of analytical calculations.In this paper, solutions for some nonlinear Ermakov and Riccati equations are calculated using this proposed method. It is shown by direct substitution that the obtained solutions in the form of power series satisfy the considered nonlinear equations of Ermakov and Riccati with a known accuracy. Solutions of nonlinear Ermakov and Riccati equations can be used to describe the chemical and physical properties of nanostructures at the quantum level. Besides, solutions of nonlinear Ermakov and Riccati equations can be successfully applied in solving stationary and time-dependent Schrodinger equations.
Keywords: ordinary differential equations, Ermakov equation, Riccati equation, mathematical modeling, power series, Maple computer system.
Zamulin I.S., Gilubnichiy A.A., Chepkasov I.V., Baidyshev V.S.
Methods for describing the reactivity of transition metal nanoparticles — page 292
Abstract: Using modern calculations from first principles, in this work we systematically studied the adsorption of atomic oxygen on the surface of nanoparticles of fcc metals Ag, Cu, Pd consisting of 79 atoms. Two models were considered to describe the reactivity of transition metals based on the d-band center of surface atoms, as well as on the basis of the generalized coordination number. Both methods for predicting the adsorption energy of oxygen atoms at different sites have shown good results, however, the method based on the generalized coordination number is computationally simpler, since this method requires information only about the structure of the particle, while the d-band center model requires electronic structure calculations. The obtained values of the oxygen adsorption energy and d-band center correspond to the known literature data. The most favorable positions for the adsorption of an oxygen atom are on the (100) plane and are hollow consisting of 4 atoms and do not depend on the type of metal under consideration. The highest adsorption energy of the oxygen atom was observed in the case of copper nanoparticles.
Keywords: transition metals, nanoparticles, generalized coordination number, adsorption, electron density functional theory.
Magomedov R.A., Akhmedov E.N.
Water vapor P-ρ-T properties calculation in the temperature range from 773 K to 1673 K — page 298
Abstract: The paper presents the calculation of isotherms of the equation of state of water vapor in the temperature range from T = 773 K to T = 1673 K. The calculation was made using a specially developed software module “Fract EOS”. An approach that improves the accuracy of calculations of the previously described method is proposed. If there are tabular data of the P-V-T (P-ρ-T) ratio for several temperatures and the pressure dependences of the fractional derivative exponent α(ρ) (which is fitting parameter for the proposed model) obtained from them, then it is possible to obtain the dependence α(ρ) for any temperature within the range. After that, the equation of state can be calculated at a given temperature with high accuracy, without fitting α by experimental values. The results obtained are in good agreement with experimental data. It is shown that proposed method is suitable for calculating isotherms in the temperature ranges not presented in tabulated reference data.
Keywords: equation of state, integral-differentiation of fractional order, Maxwell relations, Helmholtz potential, partition function, water vapor, isotherm, thermophysical properties.
Talyzin I.V., Samsonov V.M., Bogdanov S.S., Sdobnyakov N.Yu.., Grigoryev R.E., Pervikov A.V., Mishakov I.V.
Identification of complex core-shell nanostructures from the radial distributions of the local density of components — page 307
Abstract: The paper is devoted to the substantiation and further development of the approach to the analysis of the mesoscopic and integral structure of binary metal nanoparticles from the radial distributions of the local density of the components. As an example, the local density distributions of Ni and Al obtained using the results of molecular dynamics modeling of binary Ni-Al nanoparticles with an initial uniform distribution of components and Ni@Al core-shell icosahedral nanostructures are considered. Both patterns demonstrate the surface segregation of Al atoms during relaxation and subsequent quenching of the initial configurations containing 5000 atoms in 1:1 ratio (nanoparticle radius 3 nm). During cooling, the temperature of the nanoparticles decreased from 1000 K to 0,01 K with a low for atomistic simulation cooling rate. Experimentally binary Ni-Al nanoparticles with a radius of about 100 nm (76Ni:24Al at.%) were synthesized by the wire electric explosion. The experimental intensity distributions obtained from the data of energy-dispersive analysis under the action of an electron beam are presented and analyzed. These distributions correspond to a greater extent to the initial configurations in our molecular dynamics experiments, i.e., they are obviously nonequilibrium. At the same time, it was concluded that the final molecular dynamic configurations are also not entirely equilibrium.
Keywords: core-shell nanostructures, Ni-Al nanoparticles, radial density distributions, embedded atom method, tight binding potential, molecular dynamics, wire electric explosion method, energy- dispersive analysis.
Tvardovskiy A.V.
General phenomenological approach for the description of adsorption and absorption equilibria — page 321
Abstract: Up to the present time, the construction of a general theory of the equilibrium adsorption is a very urgent task. In the present paper, a general phenomenological approach is developed to describe both adsorption and absorption equilibria. It was shown that under certain assumptions, the resulting equation transforms into the well-known classical Henry, Langmuir, Brunauer-Emmett-Teller equations with constants having a clear physical meaning. Thus, the constant in the Henry equation is determined by the temperature, the specific surface of the adsorbent, the size of the adsorbate molecules, the molar mass of the adsorbate and the isosteric heat of adsorption (the energy of interaction of the adsorbate molecules with the surface of the adsorbent). In the derived Brunauer-Emmett-Teller partial equation, in contrast to the classical version, a clear dependence of the equation constant on the specific physical characteristics of the adsorption system is indicated for the first time. It is determined by the concentration of adsorbate molecules in the liquid phase at the temperature under consideration, the concentration of adsorbate molecules during the formation of a dense monolayer on the surface of the adsorbent, the energy of interaction of adsorbate molecules with the
surface of the adsorbent and the heat of condensation. The presented approach can serve as a basis for modeling a variety of adsorption and absorption phenomena, including adsorption on microporous adsorbents.
Keywords: adsorption, adsorbent, absorption, thermodynamics of phase equilibria, Henry equation, Langmuir equation, Brunauer–Emmett–Teller equation.
Yurov V.M., Portnov V.S., Mausymbayeva A.D.
Thickness of the surface layer of as-class hydrocarbons — page 331
Abstract: The aim of the work is to build a model of the surface layer of objects (crystals) and to elucidate the role of surface energy in physical processes occurring in the nanoscale region. Frame hydrocarbons of the adamantane type, which have a highly symmetrical diamond-like structure, were chosen as objects. On the basis of an empirical model, the thickness of the surface layer and the surface energy of framework hydrocarbons were determined for the first time. In practice, this is very important, since all physical and chemical processes significant in operation occur through the surface layer. For adamantane, the thickness of this layer is 21.6 nm, and for diamond it is 8.2 nm, that is, they represent a nanostructure. Such a difference in the thickness of the surface layer of the two types of structures causes their sharp difference in their properties, in particular, in their surface energy, which determines their mechanical properties. For adamantane, the surface energy is 378.7 mJ/m2, and for diamond it is 9400 mJ/m2. In practice, researchers have found that under shock-wave action, the degree of adamantane→diamond transformation is almost 30%. The work of adhesion for frame hydrocarbons is 400–500 mJ/m2, and internal stresses are 35–45 MPa, which in the surface layer lead to a decrease in adhesive strength and the inverse Hall-Petch effect.
Keywords: surface layer, nanostructure, surface energy, atomic volume, size effect, hydrocarbon, adamantane, diamond, empirical model.
3. FIRST PRINCIPLES AND ATOMISTIC MODELING — page 342
Andre E., Tsirulev A.N.
Modeling of entangled states in qubit clusters — page 342
Abstract: The model of universal quantum computation, which uses quantum circuits consisting of one-qubit and two-qubit logic elements, is implemented in several existing quantum-computing devices. In the last decade, the idea of using multiqubit gates has become very relevant, since this, in the future, will reduce the noise level of quantum circuits. The main resource of quantum computing is the entanglement of individual qubits that form a cluster. Despite the actuality of this issue, so far only a few examples of the simplest logic elements with entanglement are considered in theory for a system of three qubits (Toffoli element and double controlled NOT). This work is devoted to mathematical modeling of the entangled states of quantum systems composed of several qubits. A mathematical method is proposed for the exact or approximate construction of Hamiltonians generating the required unitary transformations. It turns out that the approach based on the representation of Hamiltonians and unitary transformations in the Pauli basis is the most suitable in this context for two reasons: firstly, the Pauli basis forms the Lie algebra of the corresponding unitary group; secondly, there are only real coefficients in the decompositions of Hamiltonians and state density operators in this basis. The method is considered in detail on the example of a three-qubit cluster driven by a ternary Hamiltonian to obtain the Greenberger-Horn-Zeilinger entangled state. For this system, the thermal state is also studied and the corresponding density operator is obtained.
Keywords: quantum gate, quantum entangled state, unitary transformation, decomposition of Hamiltonian, Pauli basis, Greenberger-Horn-Zeilinger state.
Blinova A.A., Blinov A.V., Pirogov M.A., Ogurkov K.A., Maglakelidze D.G., Yakovenko A.A.
Computer quantum chemical modeling of the interaction of calcium phosphate with amino acids — page 352
Abstract: In this work, a quantum-chemical modeling of the process of interaction of calcium phosphate with amino acids was carried out. Within the framework of the quantum chemical modeling, the total energy of the molecular complex E, the energy difference between the amino acid molecule, and the «calcium phosphate – amino acid» system ∆E, the energy of the highest occupied molecular orbital EHOMO, the energy of the lowest free molecular orbital ELUMO, and the chemical rigidity of the system η were calculated. In this work, 8 essential proteinogenic amino acids were considered as stabilizers. As a result of the data analysis, it is found that all the presented interactions are energetically favorable: ∆E > 3370 kcal/mol, and the chemical rigidity of these interactions is in the range from 0,049 to 0,090 eV. Based on the obtained data, the most stable and energetically favorable interaction is the «calcium phosphate – Lys» system (∆E = 3395,848 ± 0,151 kcal/mol, η = 0,085 ± 0,006 eV). To confirm the data obtained, the samples were examined by IR spectroscopy. It has been established that the interaction of the amino acid lysine with the surface of a calcium phosphate particle occurs when oxygen is bound to amino groups in the lysine molecule.
Keywords: quantum chemical modeling, calcium phosphate, valine, leucine, isoleucine, methionine, threonine, lysine, phenylalanine, tryptophan, chemical rigidity, IR spectroscopy method, total energy of the molecular complex.
Vasilyev S.A., Puitov V.V., Talyzin I.V., Samsonov V.M.
Comparative molecular dynamics simulation of synthesis of silver nanoparticles from the gas phase — page 362
Abstract: A comparative molecular dynamics simulation of the gas-phase synthesis of Ag nanoparticles is carried out employing two different types of many-particle potentials of the interatomic interaction: a potential corresponding to the embedded atom method and the tight-binding potential. The initial temperature was varied from 1000 to 3000 K, and then it gradually decreased to 77 K, which corresponded to the temperature of liquid nitrogen. The results obtained using alternative force fields are consistent with each other, but, at the same time, they significantly differ both in the dynamics of evolution of the system and in the
obtained final configurations of nanoparticles. Increasing the cutoff radius of the tight binding potential significantly changes the rate of the nanoparticle formation. However, an increase in the cutoff radius when using the embedded atom method does not affect the evolution of the system. The configurations obtained as a result of simulation using the embedded atom method are characterized by a smaller size and a shape close to spherical, while when using the tight binding potential, larger nanocrystals with an elongated shape are formed.
Keywords: silver nanoparticles, gas-phase synthesis, embedded atom method, tight binding potential, molecular dynamics.
Veresov S.A., Savina K.G., Veselov A.D., Serov S.V., Kolosov A.Yu.., Myasnichenko V.S., Sdobnyakov N.Yu.., Sokolov D.N.
To the problem of investigating the processes of structure formation in four-component nanoparticles — page 371
Abstract: Various types of configurations of the Au-Cu-Pd-Pt four-component nanosystem, including complex core-shell structures, have been studied. The Monte Carlo method was used as a simulation method, the interatomic interaction was described by the tight-binding potential, i.e. the Gupta potential. According to the results of a series of computer experiments, it was found that four-component nanoparticles of this system do not tend to form a core-shell structure, even though gold atoms have an increased surface segregation. The melting temperatures for the nanosystems under study have been determined. The obtained values are in the range from 1100 K to 1250 K and weakly depend on the composition of nanoparticles (the ratio of the number of atoms). A stoichiometric composition based on these metals was found, for which, during cooling, an FCC crystal structure with inclusions of the HCP phase is formed. However, no distinctive features in the nature of segregation for this stoichiometric composition have been established. All considered stoichiometric compositions in the studied temperature range were stable with respect to decomposition.
Keywords: Monte Carlo method, tight-binding potential, four-component nanoparticles, structure formation, melting temperature, stability.
Gafner Yu.Ya., Ryzhkova D.A.
Simulation of the synthesis process Cu-Au nanoparticles from a gas medium: general analysis — page 383
Abstract: The process of synthesis of CuAu nanoclusters from a high-temperature gas phase was simulated. The molecular dynamics method was used. 91124 Cu and Au atoms were used as the initial configuration. The atoms were arranged randomly in space, the average distance between them was 30 Bohr radii. The set of parameters was chosen in such a way as to simulate the conditions of the inert gas condensation. This system was cooled with a thermal energy removal rate of 108 K/s. Based on the data obtained, conclusions were drawn about the main stages of the evolution of the model system. It is shown that the initial stage of synthesis consists of five different stages, which gradually lead to the formation of primary spherical nanoparticles of the CuAu binary alloy. At the final stage, the eventual transformation of the formed primary nanoparticles takes place. The initial atomic atmosphere almost completely disappears and spherical binary nanoparticles are formed, a characteristic feature of which is the displacement of gold atoms to the surface.
Keywords: nanotechnology, nanopowders, computer simulation, tight-binding model, nanoparticles, copper, gold.
Gafner Yu..Ya.., Ryzhkova D.A.
Analysis of the chemical composition of Cu-Au nanoparticles during simulation of the process of gas-phase synthesis — page 391
Abstract: The process of synthesis of CuAu nanoclusters from a high-temperature gas phase was simulated. The molecular dynamics method was employed, 1124 Cu and Au atoms were used as the initial configuration. The computer model of synthesis from the gas phase was based on an experimental setup located at the Budker Institute of Nuclear Physics SB RAS. On the basis of the data obtained, conclusions were made concerning the real chemical composition of clusters at the final stage of formation. It is shown that clusters larger than 400–500 atoms adhere to the given target ratio. The maximum deviations from the target ratio were recorded only for atomic vapor of stoichiometric composition. In other cases, with a reduction in the percentage of gold atoms in the initial pair, the deviations of clusters from the required composition decreased. It was determined that the reason for this was a different crystal structure of the nanoparticles obtained by modeling.
Keywords: nanotechnology, nanopowders, computer simulation, tight-binding potential, nanoparticles, copper, gold.
Gafner Yu..Ya.., Ryzhkova D.A.
Influence of gold atoms on the structure of Cu-Au nanoparticles at simulation of the process of gas-phase synthesis — page 399
Abstract: The article considers the process of formation of binary Cu-Au nanoclusters with different target composition from a high-temperature gaseous medium. The molecular dynamics method was used. The main attention was paid to studying formation of the crystal structure in such clusters and determination its type. It is shown that an increase in the percentage of gold atoms in the primary gaseous medium significantly affects the formation of the internal structure of simulated nanoparticles. With a relatively small increase in the proportion of gold atoms, there is a complete disappearance of clusters with the fcc structure. The formation of nanoparticles with, as a rule, five-particle symmetry is observed. In this case, the Dh configuration prevails. If both precursors are evaporated at the same rate, then an increase in the percentage of gold atoms in the gas mixture leads to the fact that CuAu clusters are often unable to form any clearly distinguishable crystalline form, due to which approximately every fourth cluster was fixed in the amorphous state. We concluded that the cause of this phenomenon may be the separation of atoms of different types, which is typical for binary nanoparticles of the studied chemical composition.
Keywords: nanotechnologies, nanopowders, computer simulation, tight-binding model, nanoparticles, copper, gold.
Kartashynska E.S.
Temperature dependences of the molecular area of surfactant 2D monolayers at the air/water interface — page 408
Abstract: The dependences of the molecular area (Ac) at the onset of the transition from the liquid-expanded to liquid-condensed (LE-LC) phase for 2D surfactant monolayer on the temperature and chain length are considered for seven surfactant classes at the air/water interface. A thermodynamic model of the amphiphilic monolayer behavior (taking into account the nonideality of mixing entropy) is used to evaluate Ac, as well as a quantum chemical approach that allows an assessment of the thermodynamic and structural parameters of surfactant associates. The calculated Ac values adequately reflect the experimental temperature dependence for the considered phase transition: the temperature increase leads to a decrease of the area per surfactant molecule with the fixed chain length and vice versa lengthening of the surfactant carbon chain at a fixed temperature results to the Ac value increase. The average values of the slope in the Ac = f(T) dependences for the regarded surfactant classes are in the range of 0,57-1,32 Å2/°C. The estimation of the (dAc/dn)T value shows that the best agreement of the calculated and available experimental data is achieved for saturated carboxylic acids and dialkyl-substituted melamine. The obtained results demonstrate applicability of the proposed approach for predictive purposes.
Keywords: 2D monolayer, clusterization Gibbs energy, unit cell, phase transition, thermodynamic model.
Kolosov A.Yu.., Mitinev E.S., Taktarov A.A., Myasnichenko V.S., Bazulev A.N., Sdobnyakov N.Yu..
Regularities of structural transformations in bimetallic Pd-Pt nanoparticles — page 419
Abstract: The processes of melting and crystallization of bimetallic Pt- and Pd-based nanoparticles have been studied by the method of molecular dynamics. The possibility of obtaining stable nanoparticles containing 3000 and 4000 atoms in the temperature range from 500 K to 1600 K is established. The concept about the possibility of fixing the temperatures of starting and ending of the phase transition for melting and crystallization is confirmed which was put forward earlier for monometallic platinum and palladium nanoparticles. The analysis shows that during the cooling of Pd-Pt nanoparticles with an initially uniform distribution of components, formation of a mixed structure with a surface monolayer of Pd atoms is observed. The possibility of structural segregation in bimetallic Pd-Pt nanoparticles containing 3000 and 4000 atoms is shown. At the same time, these two sizes correspond to different scenarios. For bimetallic nanoparticles with 3000 atoms, local zones are mainly polyhedral, and for bimetallic nanoparticles containing 4000 atoms, formation of extended band structures is observed.
Keywords: molecular dynamics method, bimetallic nanoparticles, platinum, palladium, segregation, structural transformations, stability.
Komarov P.V., Malyshev M.D.
Investigation of welding process of vitrimer-based material: meso-scale simulation — page 435
Abstract: A self-healing epoxy material is considered, based on bisphenol A diglycidyl ether and atricarboxylic fatty acid hardener, belonging to a new class of polymers called vitrimers. The res toration of the integrity of such systems in the case of a damage occurs due to the exchange reaction of covalent bonds between the comonomers forming a polymer network. In our previous work, we have developed a model of this material based on the method of reactive dissipative particle dynamics. In this work, we apply our model to study the welding process of vitrimer samples cut into two parts. The control of the integrity of the structure of the systems was carried out using a topological analysis by calculating the distributions over the lengths of simple cycles and the density of the number of load-bearing circuits. It has been shown that the rate of restoration of the integrity of the systems is determined by the concentration of the catalyst and the degree of crosslinking of the polymer. The results obtained also indicate that in the case of a high degree of crosslinking of the polymer, as well as a low catalyst concentration, the structure of the system is highly inhomogeneous.
Keywords: vitrimers, network polymers, mesoscopic modeling, dissipative particle dynamics, bond exchange reaction.
Kuznetsov Yu..A., Lapushkin M.N.
Electron-stimulated desorption of rubidium atoms adsorbed on the surface of gold-rubidium intermetallide — page 450
Abstract: The calculation of the density of states of various thicknesses of the 2D-layers of the intermetallic compound RbAu has been carried out. 2D-layers of intermetallic compound RbAu are simulated by supercells RbAu (111) 2×2×2. For a monolayer 2D-layer of an intermetallic compound RbAu the presence of a bandgap with a width of 2,70 eV has been established. An increase in the thickness of the 2D-layers of the intermetallic compound RbAu to three monolayers showed a decrease in the bandgap to 0,80 eV. A further increase in the thickness of the 2D-layers of the intermetallic compound RbAu leads to the disappearance of the band gap, which indicates a semiconductor-metal transition for the 2D-layer of the intermetallic compound RbAu with a thickness of four monolayers. The valence band of the 2D-layer of the intermetallic compound RbAu is formed mainly by Au 5d
electrons, with an insignificant contribution from Au 6s and Au 6p electrons. The conduction band of RbAu is formed mainly by Au 6p electrons with an insignificant contribution of electrons Rb 5s.
Keywords: electronic structure, ab initio calculation, intermetallic compounds, rubidium auride, 2D-layer.
Kurbanova E.D., Polukhin V.A.
Strength and functional characteristics of hexa and pentagonal 2D materials. Hydrogen — page 458
Abstract: An analysis of synthesized unique two-dimensional 2D materials with nanolayer hexagonal and pentagonal structures (based on carbon, silicon, tin, binary compounds CN2, BN2, PdSe2 and ternary compounds – BCN, CNP, PdSSe, Zn2C2P2) was carried out. The synthesis of these materials was performed by the chemical vapor deposition or metal epitaxy on pre-prepared substrates. The strength and functional characteristics (electronic, optical) of the created models were also analyzed using the DFT theory in the form of triple monolayers with double-sided deposition of hydrogen on the surface of the p-Si2C4 monolayer: hydrogen/p-Si2C4/hydrogen. It was found that the p-Si2C4-4H layer with its two-sided hydrogen adsorption and good properties was the most dynamically stable. This article also presents relatively recently obtained hexa- and pentagonal two-dimensional materials not only for the elements C, Si, Ge, B, but also for Cu1–xNix, Ti1–xNix alloys and Bi1–xSbx, CN2, BN2, PdSe2, etc. compounds. So, with the new unique materials created – the synthesis of superstrong, thermostable nanocomposites, superconducting layered composites (based on Bi, Hg and Sb), prospects are opening up for the development of nanoelectronics, spintronics, computer technology, as well as the creation of portable strain gauges, pressure sensors, gas sensors and dialysis catalysts for water dialysis with the release of hydrogen and oxygen.
Keywords: hexagonal and pentagonal structures of 2D materials, material modeling, mechanical properties, catalytic properties.
Myasnichenko V.S., Sokolov D.N., Bazulev A.N., Nepsha N.I., Ershov P.M., Sdobnyakov N.Yu..
Construction of a lattice Monte Carlo model of layer-by-layer growth of bimetallic nanoparticles — page 468
Abstract: Based on the Metropolis software, a lattice statistical model of the layer-by-layer growth of bimetallic nanoparticles has been implemented. As an example, this paper analyzes two types of lattices: fcc and decahedral. On their basis, the growth of free Au-Ag nanoparticles is modeled in three modes that differ in growth stages: 3, 4, or 7 bimetallic layers are added. The interatomic interaction is set by the tight-binding potential, however, the constructed model does not exclude the possibility of using other modifications of the proven many-particle potentials. The change in the specific potential energy of entire nanoparticles and gold atoms during layer-by-layer growth is analyzed. The dependence of the number of mixed bonds on the layer number is studied for the entire nanoparticle and for the gold subsystem.
Keywords: computer experiment, Monte Carlo method, Metropolis scheme, layer-by-layer growth, bimetallic nanoparticles, mixed bonds.
Pan’kin N.A.
Molecular dynamic simulation of heating of titanium nanoclusters — page 479
Abstract: The melting of titanium nanoclusters Tin (n = 3599, 28725, 97045) with different heating rates (from 0,1 to and 10,0 TK/s) was studied by the molecular dynamics method. Molecular dynamics simulation was carried out using the LAMMPS program on a multiprocessor computer. A many-particle potential of interatomic interaction was used. The crystal structure of a titanium nanocluster upon heating passes into the liquid phase through the formation of a system of atoms (islands) with an ordered local environment near the melting point. The appearance of the latter is due to the non-equilibrium of the simulated heating process – the system does not have time to relax to an equilibrium state for a chosen temperature. The melting temperature was taken as the average value between the temperatures of the beginning and finishing of the phase transition process. The temperature of the beginning of melting corresponded to the state of completion of formation of individual islands. At the end of melting, the nanostructure is characterized by a completely disordered structure. It is noted that the melting temperature increases with the size of the nanoparticle and the rate of its heating. The limiting temperatures of the considered phase transition (at N → ∞) are significantly lower than the melting temperature of the bulk titanium.
Keywords: titanium, nanocluster, melting point, heating rate, structure, islands, molecular dynamics method.
Ryzhkova D.A., Gafner S.L., Gafner Yu..Ya.., Cherepovskaya A.A.
Molecular dynamics study of the size limit of the transition of silver nanoclusters with an initial amorphous substructure into FCC phase — page 490
Abstract: Silver nanoclusters with diameter of 3,0 to 7,0 nm were studied by the molecular dynamics method using the tight binding potential TB-SMA (second moment approximation of tight-binding potential). A search was made for the stability limits of structural modifications of these nanoclusters for determination of the size limit of the thermally induced structural transition from the initial amorphous morphology to the fcc phase. The new data were compared with the results of previous studies for Ag nanoparticles up to 2,0 nm in size with initial fcc and amorphous structures. It is shown that the studied nanoclusters can be conditionally divided into three categories. The first one (N < 100 atoms) is characterized by partial preservation of the original morphology. For the second one (d < 4,0 nm), there is competition between the icosahedral and decahedral structures. And for the thirds (d > 4,0 nm), the mixed fcc/hcp phase predominates. In this case, the size limit of the transition from the initial amorphous morphology to the structure characteristic for the bulk matter is a diameter of about 7,0 nm.
Keywords: nanoclusters, silver, computer simulation, structure, tight binding, phase transitions, structural stability.
Savina K.G., Galuzin I.R., Kolosov A.Yu.., Bogdanov S.S., Veselov A.D., Sdobnyakov N.Yu..
On the processes of segregation and stability of bimetallic nanoparticles Ni@Ag and Ag@Ni — page 499
Abstract: This work studied bimetallic nanoparticles Ni@Ag and Ag@Ni with the total number of atoms 4000 by the molecular dynamics method using the tight-binding potential. The pattern of segregation and structural formation is established and its characteristics are described. Based on the analysis of the behavior of the calorie curves of the potential part of the internal energy, the melting and crystallization temperature was determined. The data obtained suggest that the processes of segregation in Ni@Ag and Ag@Ni nanoparticles are associated with the nanoparticle stability. The silver shell loses its stability above 900 K, while the nickel core remains solid and retains its structure. At the same time, in Ni675@Ag3325 nanoparticles the processes of the surface segregation of the nucleus atoms were less pronounced, whereas in Ag675@Ni3325 nanoparticles silver atoms actively segregated onto the surface of the nanoparticle. The features and fundamental differences in the processes of melting and crystallization of these nanosystems, as well as the temperature ranges of their stability, are analyzed. The relationship between the degree of intensity of segregation processes of nanoalloys during modeling and the stability of these systems is shown.
Keywords: molecular dynamics method, bimetallic nanoparticles, nickel, silver, segregation, structure formation, stability, core-shell.
4. PHYSICAL AND CHEMICAL BASES OF NANOTECHNOLOGIES — page 512
Belyakova R.M., Kurbanova E.D., Polukhin V.A.
Alloying and strain hardening of high-entropy membrane storage nano and crystalline alloys — page 512
Abstract: The article presents both molecular dynamics calculations of binary Fe–Ni alloys and experimental studies of Ti and Co alloyed nanocrystalline alloys with a B2–Ti(Fe, Co) matrix structure as well as bcc-(Nb, Ti) and B2– eutectic phases Ti(Fe, Co). The structures of membrane alloys based on Fe–Ni (arrangement of atoms in coordination polyhedra and interatomic distances between atoms), as well as the kinetics of hydrogen – diffusion and permeability have been studied. It is shown that in the membranes of alloyed alloys with the substitution of Ni for cobalt Fe35-XCoXTi35Nb30, with an excess of Fe than for cobalt, mechanical brittleness is manifested in the B2–TiFe phase, and the plasticity of the B2 phase also decreases. At the same time, the resistance to an increase in hydrogen absorption is also weakened, up to mechanical destruction of membranes, so that in high-entropy alloys Fe0,2Ni0,2Cr0,2Co0,2Mn0,2, Fe0,2Co0,2Cr0,2 Ti0,2Al0,2 Fe and Co in equal parts. Other intermetallic alloys are also promising, having more complex compositions with high or moderate entropy, for example, Zr0,2Ti0,2Nb0,2V0,2Co0,2 and Zr0,2Ti0,2Ta0,2V0,2Co0,2, in addition to hydrogen evolution, also have storage properties. Within the framework of molecular dynamics, the effect of strain hardening of membrane HEA alloys is experimentally presented – the mechanism of synergy with multiple deformation. As a result of such hardening, a partial transformation of the austenitic phase into a
martensite phase occurs with the formation of twinning in their fcc/hcp grains and the formation of a two-phase matrix structure.
Keywords: nanocrystalline alloys, modeling, alloying, work hardening, matrix structure, eutectic phases, high-entropy alloys, austenite, martensite, membranes, hydrogen, hydrides.
Bogdanova E.A., Skachkov V.M., Nefedova K.V.
Preparation of biocomposites based on nanoscale hydroxyapatite with titanium compounds — page 521
Abstract: The article discusses the possibility of obtaining a hardened composite material with a porous structure based on nanostructured hydroxyapatite (HAP) synthesized by precipitation from a solution. The new material by the mechanochemical synthesis of HAP with reinforcing additives of titanium compounds was obtained. The synthesized samples are certified using some modern physico-chemical methods of analysis. The influence of the qualitative and quantitative composition of the composite on the sintering processes, porosity, strength characteristics, the degree of dispersion and morphology of the studied samples is shown. It has been experimentally established that a sample based on hydroxyapatite, reinforced with non-stoichiometric titanium dioxide of the composition Ca10(PO4)6(OH)2 – 15%TiOx has the maximum strength characteristics and constant composition. The composite material, having a dense uniform structure with a high degree of crystallinity and a developed porosity, is a promising material for further research in order to introduce it into medical practice. A patent application has been filed on the developed composite material.
Keywords: hydroxyapatite, titanium oxide, titanium compounds, composite biomaterials, crystallinity, microhardness.
Bolotov A.N., Novikova O.O., Meshkov V.V.
Viscometric studies in the process of synthesis of magnetic lubricant nano-oils — page 531
Abstract: In the field of tribology, magnetic lubricating oils are promising, in which polymers are used to increase their colloidal stability, but their use is limited by the low magnetization of the colloid. It is possible to increase the magnetization of nanooils by synthesizing polymer shells directly on the surface of magnetic particles in the process of obtaining nanooils. The features of the technology for the synthesis of magnetic lubricating nanooils with polymeric solvation shells on particles, which protect them from coagulation, are described. Polymerization of hydroxy acid molecules proceeds by the mechanism of polycondensation on the solid surface of magnetite. The viscosity of the magnetic colloid increases due to the increase in the thickness of the solvate shell. Proceeding from this, a differential equation is proposed, which shows the dependence of the growth rate of the colloid viscosity on the rate of the polycondensation reaction. An experimental verification of the equation showed that it is fulfilled with an accuracy up to 8%. The resulting equation makes it possible to determine an important thermodynamic characteristic – the activation energy of the process of synthesis of polymer shells on the surface of dispersed particles. For calculations, it is necessary to
know the rate of change in the viscosity of a colloid with a dispersion medium without a monomer (hydroacid). Therefore, in the process of the polymer synthesis, samples of the intermediate magnetic colloid of a small volume are taken, which are used to determine the viscosity of the colloid and dispersion medium containing monomers. Then the viscosity of the colloid with a pure dispersion medium is found, which is necessary for calculating the activation energy of the polycondensation reaction. According to estimates, the error in determining the activation energy does not exceed 11%. In practice, using the values of the activation energy of polymerization, it is possible to carry out a purposeful choice of the optimal temperature-time regime for stabilizing the magnetic colloid in order to obtain a magnetic nanooil with the required viscosity and aggregative stability characteristics. Experimental studies were carried out on specially designed instruments for assessing the colloidal stability and dynamic viscosity of magnetic colloids.
Keywords: colloidal systems, magnetic lubricating nanooils, viscosity, colloidal stability, activation energy of polymerization.
Bolotov A.N., Novikova O.O.
The effect of the nanodisperse phase of magnetic oils on their lubricating properties — page 545
Abstract: The work is devoted to the study of processes occurring in the boundary lubricant layer, in which nanodisperse magnetic particles play a decisive or significant role. The friction between metal surfaces with lubricated oils of different concentrations of the magnetic nanodisperse phase was studied. The dispersion medium of magnetic oils consisted of liquids with various physico-chemical properties: dioctylsebacinate, triethanolamine, polyethylsiloxane. It has been shown that the wear intensity of surfaces with a hardness higher than that of nanoparticles monotonically increases with increasing the particle concentration, and wear is abrasive in nature. The wear rate of softer materials passes through a minimum at a particle concentration of about 2 vol.%. Magnetic separation of large agglomerates in oil allows for some time to reduce the abrasive wear until they are formed again under friction conditions. It was not possible to identify the regularities of the influence of nanodispersed particles on the friction force, it is probably insignificant. Several examples of the indirect effect of nanodispersed particles on the boundary friction are considered. In all the examples, the determining role plays huge area of the active surface of particles per unit volume of oil. For example, under conditions of friction, atomic hydrogen can be actively formed during the chemical interaction of fatty acids with the surface. Atomic hydrogen accumulates in the subsurface pores and is crystallized there. The increased pressure in the pores created by hydrogen molecules leads to an increase in wear by the peeling mechanism. The established regularities of the influence of nanodispersed particles on the rate of formation of the boundary lubricant layer and the corrosion wear of surfaces caused by surface-
active additives in magnetic oil are of scientific interest.
Keywords: nanodisperse particles, magnetic oil, grease, friction, wear.
Vostrov N.V., Solnyshkin A.V., Morsakov I.M., Belov A.N., Krylov P.N.
Investigation of the physical properties of PVDF thin films obtained by 4D printing — page 561
Abstract: In this work, we searched for the optimal way to create ferroelectric nanostructured composite materials based on 4D-printed polyvinylidene fluoride polymer films. Method fused deposition modeling allow using polyvinylidene fluoride and its copolymers not only in microelectronics as pyroelectric and piezoelectric sensors, as well as creating dynamic memory elements, organic solar cells and used in robotics. At the first stage of the work, the authors were selected optimal extrusion parameters for the manufacture of a thread from powder and granules. The next stage of the work included the analysis and determination of printing parameters by the method of layer-by-layer filament deposition to obtain the best quality of polymer films. Using scanning electron microscopy, the existence of two phases, a polar β-phase and a nonpolar α-phase, is shown, where the crystalline phase is observed in the form of lamellar crystals chaotically oriented in the α-phase matrix. Pyroelectric measurements performed by the dynamic method showed the presence of a noticeable pyroelectric response in polyvinylidene fluoride films obtained using additive technologies, bypassing the orientation extraction stage. The calculation of the pyroelectric coefficient gives values corresponding to the values of the pyroelectric coefficient for polyvinylidene fluoride samples obtained by traditional methods.
Keywords: composite, polymer ferroelectric, additive technologies, 4D printing, 3D printing, spontaneous polarization, piezoelectric effect, pyroelectric effect, scanning electron microscope.
Guseva O.S., Malyshkina O.V., Mitchenko A.S.
Effect of modifiers on the barium niobate-calcium ceramics structure — page 572
Abstract: In this work, the ceramic samples Са0,3Ba0,7Nb2O6 pure and with modifying additives (5%) SrTiO3, KTaO3 or LiTaO3 were obtained by solid-phase synthesis. All studied compositions of ceramics revealed the presence of large and small grains. It is shown that the addition of LiTaO3 to the composition of Са0,3Ba0,7Nb2O6 ceramics reduces the grain size by an order of magnitude, while the addition of SrTiO3 leads to an elongation of the grain shape. Based on the analysis of the elemental composition, it was found that the introduction of modifiers into the composition of Са0,3Ba0,7Nb2O6 reduces the excess of oxygen in the structure of tetragonal tungsten bronze, compared to unmodified Са0,3Ba0,7Nb2O6 ceramics. The maximum on the temperature dependence of the permittivity is practically independent of the type of modifier and is located in the range of 279-285°C. This is 60 degrees higher than the Curie temperature of the Са0,3Ba0,7Nb2O6 single crystal. Regardless of the measurement temperature, Са0,3Ba0,7Nb2O6 + 5%SrTiO3 material has the maximum value of the permittivity. Whereas the minimum value of the permittivity at room temperature has the Са0,3Ba0,7Nb2O6 + 5%LiTaO3 sample, and at the Curie point, the Са0,3Ba0,7Nb2O6 sample.
Keywords: piezoelectric ceramics, barium-calcium niobate, lead-free materials, modifiers, grain structure, permittivity.
Gyrdashova O.I., Stepanov A.E., Naumov S.V., Shkerin S.N.
Effect of synthesis conditions on the formation of Y3-xLaxFe5-yO12+δ/La1-xYxFe1-yO3 composite — page 583
Abstract: Glass-like composite materials with high oxygen conductivity values were obtained by growing from a homogeneous melt by the method of non-melting zone melting. A complex architecture of the composite is observed: the main phase is highly defective in cationic and anionic sublattices Y3-xLaxFe5-yO12+δ with a garnet structure, inside which the germination of filamentous crystals La1-xYxFe1-yO3 with a perovskite structure is observed. The effect of the method of synthesis of polycrystalline precursors used as raw materials for the production of the melt on the formation of the structure of composites La1-xYxFe1-yO3/Y3-xLaxFe5-yO12+δ is investigated. The composite obtained from the precursor formed by the formate method contains ~87 mol.% of the main phase.The composite obtained from the precursor formed by the self-propagating high-temperature synthesis is ~76 mol.% of the garnet phase. The obtained composites have a certain growth direction of the main phase Y3-xLaxFe5-yO12+δ <100>.
Keywords: yttrium ferrite, garnet structures, synthesis, precursors, morphology, composites, oxygen conductivity.
Devitsky O.V.
Structure and composition of thin GaAs1-x-yNxBiy films produced by pulsed laser deposition — page 593
Abstract: Uniaxial cold pressing was used to fabricate GaAs0,9Bi0,1 targets with 10% Bi content. Thin
films of GaAs1-x-yNxBiy onto a GaAs (100) substrate were obtained from the formed GaAs0,9Bi0,1 target
by pulsed laser deposition in an argon-nitrogen gas atmosphere, and their structure and composition
were studied. It is shown that on the surface of the film there are predominantly small microdroplets
with a diameter of less than 0,5 μm, formed by Bi atoms. Large microdroplets with a diameter of 2 to 6
μm consist partly of Bi and Ga. No microdroplets formed only from Ga were found. It is noted that
small Ga microdroplets are adsorbed on the surface of large Bi microdroplets without forming a GaBi
alloy. It was also found that the formation of Bi microdroplets also occurs due to the segregation of Bi
atoms on the film surface. The energy-dispersive spectroscopy data make it possible to characterize
the resulting thin films as GaAs0,995N0,015Bi0,03. The mean square roughness of the film surface was 12,2
nm. The resulting GaAs0,995N0,015Bi0,03 film has a polycrystalline structure. An analysis of the X-ray
diffraction data showed that the film grew according to the Volmer-Weber law, when islands are
nucleated and their sizes subsequently increase. The nuclei are most likely formed by GaAs, GaN,
GaAsN, GaAsBi, and GaAsNBi. The calculated full width at half height for GaAs0,995N0,015Bi0,03 was –
0,8656ʺ, and the average crystallite size was 1,6 nm.
Keywords: thin films, III-V-N-Bi, GaAs1-x-yNxBiy, pulsed laser deposition, diluted nitrides, diluted bismuthides.
Zajogin A.P., Trinh N.H., Malets M.A., Patapovich M.P.
Peculiar properties of methods for obtaining amorphous nanofilms for creating gas-sensitive sensors under the action of laser double pulses on the surface of a target containing tin — page 602
Abstract: A layer-by-layer analysis of metals and alloys has been carried out, and the possibility of deposition of nanofilms containing tin in their composition on various types of surfaces (metal, glass) under the action of dual laser pulses on a target in an air atmosphere has been studied. The experiments were carried out using the laser two-pulse multichannel atomic emission spectrometer LSS-1. The advantages of the pulsed laser deposition as a method for producing clusters and fractals are: versatility in relation to the material, the ability to exclude impurities, the flexibility of the method, and the ability of controlling the formation of film structures. The performed spectroscopic studies of the laser plasma formed by the action of two successive pulses on a target illustrate the development of methods for obtaining nanoclusters of various chemical elements. This method can be used to obtain nanofilms of not only pure metals, but also composite alloys. The possibility of obtaining nanofilms for creating gas-sensitive sensors is shown.
Keywords: double laser pulses, laser plasma, layer-by-layer analysis, deposition of thin films, nanopowder technologies, multichannel atomic emission spectrometry.
Ivanov Yu..F., Klopotov A.A., Lopatin I.V., Ivanova O.V., Petrikova T.L., Petukevich M.S., Nikonenko E.L.
Phase formation in high-chromium steel under electron-ion-plasma treatment — page 609
Abstract: The surface alloying was carried out by single-cycle and multi-cycle (5 cycles «sputtering-irradiation», in each cycle the thickness of the titanium film 0,5 µm), i.e. high-speed melting of the system «film (Ti)/(steel AISI 310S) substrate» by pulsed electron beam. Nitriding (793 K; for 1, 3 and 5 hours) was carried out under conditions of realization of the elion (electron and ion) treatment mode. The isothermal cross sections of the ternary systems of the state diagram of the Cr – Fe – Ni – Ti – N alloy formed at different stages of the complex treatment of steel are considered. It is shown that (1) irradiation of steel by a pulsed electron beam is accompanied by the formation of a structure of high-speed cellular crystallization of solid solution based on γ–Fe; (2) nitriding of steel in the initial state is accompanied by formation of nitrides of iron Fe4N and chrome CrN with a total content of 79,8 wt.%; (3) pulsed electron-beam pre-irradiation of steel leads to a decrease in the rate of nitride formation during subsequent nitriding; the total nitride content of 53 wt.%; (4) regardless of the number of alloying cycles (titanium concentration in the surface layer) after five hours of nitriding in the samples formed a surface layer of nitrides of chromium and iron (1 cycle of doping) or nitrides of chromium and titanium (5 cycles of doping).
Keywords: complex electron-ion-plasma treatment, electron plasma component heating of samples, high-chromium steel, surface alloying, phase composition.
Kapustinа G.G., Leonenko N.A.
Mechanisms of laser impact on ultra-fine mineral medium — page 621
Abstract: The development of modern technologies for the complex extraction of valuable components from refractory ores and technogenic deposits is possible on the basis of the latest achievements of fundamental sciences, a combination of physicochemical, enrichment and metallurgical processes. The paper describes the results on the impact of laser radiation on mineral samples with ultrafine «non-recoverable» gold from silt ponds-settlers of alluvial deposits in the Far East. The object of research is the impact of a source of continuous laser radiation on samples of minerals, objects of alluvial deposits containing submetric and nanosized forms of gold that are not recoverable by traditional gravity methods. The purpose of this work was to study the processes of interaction of laser radiation with dispersed mineral media containing ultrafine gold and to determine the conditions for agglomeration of ultrafine gold. Electron microscopic images of the samples were obtained using a LEO EVO 40HV microscope (Carl Zeiss, Germany) equipped with an INCA-ENERGY energy-dispersive analyzer. A model is proposed that describes the processes at the boundary of heterogeneous phases. An analysis of the discovered effect of gold agglomeration made it possible to formulate technical solutions that were reflected in patents for inventions. The discovered effect of gold agglomeration made it possible to find technical solutions in the form of patents for inventions.
Keywords: laser-induced, ultrafine, colloid-ion, gold, gold-bearing mineral products, structural ordering, scanning electron microscopy.
Klychkov N.A., Simakov V.V., Sinev I.V., Shikunov D.A.
The effect of copper and zinc oxide additives on the electrical and gas-sensitive properties of tin dioxide composite layers — page 632
Abstract: Composite thin films based CuO:SnO2 and ZnO:SnO2 with different impurity concentrations was synthesized by sol-gel method by mixing sols. The films were annealed in oxygen-containing atmosphere at 550°C. A contact system was formed on top of the films by thermal evaporation of chromium, followed by deposition through a mask onto the sample. Based on the temperature dependence of conductivity for layers based on pure tin dioxide, a local maximum of conductivity is observed in the range of 250°C, which is probably due to the thermal activation process of oxygen desorption. Conductivity of SnO2 layers was decreased as the concentration of Cu dopant. 2% Cu additive reduces the long-term conductivity drift by an order of magnitude. Arguably it’s the consequence of occurrence the low mobility complexes created by copper atoms and oxygen vacancies. The best sensitivity to ethanol vapors in all concentration range was shown by 6%Zn doped samples. Accordingly, supplementations of Cu and Zn boost sensitivity of SnO2 layers to ethanol and decrease response time by its impact at 150-300°C range.
Keywords: sol-gel method, composite gas-sensitive layers, tin dioxide, conduction drift, gas sensor’s response time.
Korolkov O.E., Pakhomov M.A., Polyakov A.V., Valiev R.Z., Stolyarov V.V.
Effect of grain size and duty ratio on the mechanical behavior of titanium under tension with pulsed current — page 639
Abstract: The influence of a high-density pulsed current on the deformation behavior of titanium with different structure refinement is studied. A comparison of the features of the deformation curves has been carried out of coarse-grained and nanostructured commercial pure Ti Grade 4 under tension with the introduction of a pulsed current. A current of various duty ratio and densities was supplied from a pulse generator to a sample in the grips of a tensile testing machine. The microstructure of a coarse-grained titanium in the sample head and near the fracture region in the longitudinal section was studied by optical microscopy. To study the microstructure of nanostructured titanium foils, the transmission electron microscopy was used. The electroplastic effect in the studied materials manifested itself in the tensile curve in the form of separate downward stress jumps. Under the same regimes of high-duty ratio pulsed current, the amplitude of stress jumps in the coarse-grained titanium is higher than in the nanostructured titanium. For a low duty ratio current the stress jumps are the same in the plastic region. A high duty ratio pulsed current in nanostructured titanium led to an anomalous hardening effect, the physical nature of which needs a further investigation. The used modes of the pulsed current did not lead to structural changes noticeable under optical magnification of the tensile samples, except for the disappearance of twins and the separation of impurity particles in the coarse-grained titanium. The fractographic fracture patterns of nanostructured titanium tested with and without current indicate ductile fracture without significant changes, which testified a minimal thermal contribution during the experiments.
Keywords: tension, titanium, nanostructure, electroplastic effect, pulsed current, fractography.
Kravchenko D.A., Medvedeva O.N.
Studies of the structure and properties of dental crowns made by selective laser melting and according to the technology of casting — page 652
Abstract: In recent times, 3D printing technologies are a young and actively developing production sector for many areas of economy, from aerospace and mechanical engineering to medicine. The obvious advantage of introduction of the additive technologies in medicine and in particular in dentistry is high accuracy in producing complex details, individually designed implants and prostheses for their maximum match with a place of injury or a substituted object, considerable reduction both the product materials and auxiliary materials usage. However, questions arise about the limits of applicability and reliability of the additive technologies with their active introduction. The properties of dental crowns made of nickel-chromium alloy NH-Dent NS vac and cobalt-chromium powder PR-KH28M6 were studied in this research. For the production of samples was used selective laser melting technology, which belongs to a number of additive technologies, and the casting technology in the mold. A comparative analysis of the microstructure of the samples, the surface profile and the Vickers hardness was carried out.
Keywords: additive technologies, medicine, dentistry, selective laser melting technology, selective laser melting, microstructure, surface profile, hardness of samples.
Masloboeva S.M.
Analysis of investigations of the lithium niobate charge LiNbO3:Mg synthesized on the basis of Nb2O5:Mg precursors of different genesis — page 662
Abstract: An analysis was made of studies on the preparation of a charge of lithium niobate used for growing crystals LiNbO3:Mg by the Czochralski method. The charge was synthesized on the basis of precursors Nb2O5:Mg of different genesis. The results of studies of the mixture by X-ray phase analysis, atomic emission spectrographic analysis, gas chromatography-mass spectrometry, mass spectrometry with inductively coupled plasma and laser ablation are presented. It has been established that in the studied systems, a uniform distribution of magnesium impurities in the charge is observed, which leads to the production of crystals of high optical quality with impurity distribution coefficients above unity. It has been shown that the presence of organic inclusions makes it possible to introduce more magnesium into the growing crystal. The results are of great importance in the technology of growing single crystals of lithium niobate when choosing a method for the synthesis of a charge in order to use the crystals obtained from it in specific areas of technology.
Keywords: niobium pentoxide, genesis, doping with magnesium, synthesis of lithium niobate charge, impurity distribution, single crystal, optical quality.
Nagaplezheva R.R., Orakova M.M., Kushkhova M.Yu.., Tseeva F.M., Mishaev H.A.
Influence of vacuum-plasma treatment modes on the surface photo-EMF of single-crystal silicon — page 671
Abstract: Plasma technologies in the last quarter of the twentieth century made a real scientific and technological revolution in microelectronics. Having come to the world of microelectronics technology as a necessary alternative to liquid etching, which had exhausted its resource by that time, plasma or «dry» technologies became the main tool for creating elements of electronic products. The 21st century, undoubtedly, began and proceeds under the sign of the improvement of such technologies in solid-state electronics. Plasma technologies include a set of methods for depositing thin and ultrathin layers on a semiconductor substrate, as well as a set of methods for dimensional etching of such layers with specified etching parameters. If we consider the methods of size etching using dry technologies, it should always be taken into account that the whole range of such methods is wide. Some methods, such as radical and plasma-chemical etching, imply a mild, purely chemical interaction of the plasma medium with the substrate material, resulting in the formation of a volatile etch product and its removal (pumping) from the plasma volume. Another group of «dry» methods includes methods of purely physical impact of high-energy plasma particles on the surface of the material and the removal of atoms from the surface only as a result of sputtering of the material. The surface photo-EMF method was used to study the real surface of single-crystal p-type silicon in the temperature range T = 289-473 K before and after plasma treatment. A significant difference was found in the surface electronic states spectra obtained by heating and cooling the samples. Heating leads to desorption of gases and dissociation of water molecules in the surface layer, which reduces the surface potential by an order of magnitude.
Keywords: plasma, photo-EMF, plasma surface treatment, silicon, surface electronic states.
Nalimova S.S., Shomakhov Z.V., Gerasimova K.V., Punegova K.N., Guketlov A.M., Kalmykov R.M.
Gas-sensitive composite nanostructures based on zinc oxide for detecting organic solvent vapors — page 678
Abstract: The paper shows the possibilities of using ZnO-Fe composite structures as gas-sensitive layers for detecting organic solvent vapors exemplifying on isopropyl alcohol. Composite structures were formed based on zinc oxide nanorods synthesized by the hydrothermal method, due to changes in their composition in a ferrous sulfate solution. The chemical composition of the surface was studied using X-ray photoelectron spectroscopy. It is shown that when using a ferrous sulfate solution with a concentration of 0,025 mol/l, iron and zinc atoms are observed on the surface. An increase in the concentration of the solution to 0,05 mol/l leads to the deposition of iron oxide particles on the surface of the nanorods. The study of some gas-sensitive characteristics was carried out at 250°C when exposed to isopropyl alcohol vapors in the concentration range from 200 to 1000 ppm. It was found that the response value of composite structures ZnO-Fe (0,025) exceeds the corresponding value for the zinc oxide nanorods, that may be due to the high content of oxygen vacancies in the composite sample.
Keywords: zinc oxide, gas sensors, composite nanostructures, X-ray photoelectron spectroscopy, organic solvent.
Nikolaychuk P.A.
Electrodeposition of silver nanoparticles for the development of electrochemical sensors: a short review — page 688
Abstract: In the present review the studies performed in the last two decades devoted to the electrodeposition of silver nanoparticles on the surface of carbon electrodes and their implementation in analytical chemistry are described. Usually graphite or glassy carbon electrodes (including screen-printed electrodes) are used, and the electrodeposition is performed from the solutions of potassium nitrate and silver nitrate during a few minutes. Silver nanoparticles or modified nanocomposites including silver nanoparticles are then immobilized on the surface of the electrodes, and obtained electrochemical sensors are capable to determine various compounds using different voltammetric methods with excellent selectivity and very good linearity range and precision. The described methods of analysis allow the determination of microgram quantities of hydrogen peroxide, glucose, cholesterol, methyl parathion, Pb2+ ions, chloramphenicol and metronidazole, doxorubicin, entacapone, tyrosine and tryptophan, lamotrigine, chromium (VI), antimony (III), trinitrotoluene, oligonucleotides and the bacterium Pseudomonas aeruginosa.
Keywords: silver nanoparticles, glassy carbon electrode, graphite electrode, electrodeposition, electroanalysis, voltammetry.
Skachkov V.M.
Features of dynamics change of properties of diffusion-hardening solder at various conditions — page 699
Abstract: A study was conducted of the change in the hardness of diffusion-hardening solder based on a low-melting gallium alloy: gallium-tin-zinc when interacting with the Spherical copper-tin alloy powder (SCTAP5) under normal conditions (temperature 25°C) and subjected to low-temperature (125°C) heat treatment. Mechanical properties are estimated by measuring microhardness at various time intervals. A differential thermal analysis was carried out, with calculations of thermal effects. The phases formed as a result of diffusion hardening were determined by X-ray phase analysis, and the parameters of the crystal lattices of the phases were compared under different conditions of diffusion hardening. It is shown that at different processing temperatures, different phases are formed – nanoscale intermetallic compounds, and with the help of a scanning electron microscope, the phase of tin released as a result of physicochemical transformations is found. It has been experimentally proved that diffusion-hardening solder without heat treatment gains hardness slowly, and after 60 days the hardness approaches to that of the sample subjected to heating, which also continues to gain hardness very slowly. Thus, it is shown that diffusion-hardening solders after six hours of low-temperature treatment have not yet reached physico-chemical equilibrium.
Keywords: composite diffusion-hardening solders, exothermic effects, properties, microhardness, differential thermal analysis, X-ray phase analysis.
Skachkov V.M., Pasechnik L.A., Medyankina I.S., Sabirzyanov N.A.
Properties of diffusion-hardening composite solder modified with tungsten powders — page 707
Abstract: The article considers the regulation of the properties of diffusion-hardening solder based on a low-melting gallium-tin-zinc alloy and copper-tin alloy powder by introducing inert tungsten metal powders. After heat treatment at low temperatures (125°C), the microhardness of composite diffusion-hardening solders with a tungsten content of 5, 10, 15 and 20% is estimated. It is shown that the heat treatment at low temperatures for 6 hours does not lead the solder to reach an equilibrium state, physico-chemical transformations are still ongoing, which shows an increase in the hardness of the samples after two months. The X–ray phase analysis has been used to determine the phases formed as a result of the diffusion hardening: micro- and nanoscale intermetallic compounds and metallic tin in the form of nanoscale inclusions in the space between the grains of copper alloy powder. Due to small additions of tungsten as a filler, inert to the effects of gallium, but well wetted by it, the characteristics of diffusion-hardening solder are improved. Judging by the microhardness, the introduction of 15% tungsten is optimal.
Keywords: composite diffusion-hardening solders, metal powder, properties, tungsten, microhardness, differential thermal analysis.
Sokolova E.M., Boiko A.S., Fokina M.I., Ponomareva A.A.
Development of tetraethoxysilane-based polymer absorbing coating with an adding of the cobalt oxide for a laser surgery — page 717
Abstract: The use of generated jets as «micro incisors» finds its application in laser surgery. Such methods of laser exposure are used to remove neoplasms, such as intervertebral hernias and cysts. An optical fiber is attached to the laser, which is inserted into the hernia or cyst through a puncture needle. To increase the efficiency of laser exposure, it is necessary to accumulate energy at the end of the waveguide by forming an absorbing coating, which should have high adhesion to quartz. In this work, a study was carried out on the development of a technique for polymer films by the sol-gel method for use in laser surgery as an absorbing coating. Tetraethoxysilane was chosen as a precursor for the formation of a polysilicate mesh holding small cobalt oxide particles. Optical, morphological, and absorbing properties of coatings obtained onto quartz glasses were studied in this work. Additionally, the solutions and the obtained coatings were studied using IR spectroscopy, the results of which showed the absence of a qualitative change in the sols during long-term storage (up to 3 weeks) and the formation of a three-dimensional silicate network and cobalt oxide in the films. The study of the surface morphology of the obtained coatings showed that high concentrations of cobalt salts are not required for the uniform distribution of the synthesized cobalt oxide. The absorbing properties of the samples were tested using an IR laser and a thermal imager. Owing to the research the optimal composition of the coating for the deposition on quartz waveguides was chosen.
Keywords: tetraethoxysilane, cobalt oxide, quartz, sol-gel technology, IR spectroscopy, laser radiation, absorbing coating.
Shomakhov Z.V., Nalimova S.S., Shurdumov B.Z., Maximov A.I., Moshnikov V.A.
Zinc stannate nanostructures for fast response gas sensors — page 726
Abstract: The possibilities of using zinc stannate nanostructures as sensitive elements of fast response gas sensors are considered, which are of great interest for use in a variety of applications from the detection of toxic substances to air quality monitoring or medical diagnostics. The synthesis of zinc stannate nanostructures was carried out by hydrothermal treatment of zinc stannate nanorods in a solution of potassium stannate and urea at different concentrations of precursors. The chemical composition of the sample surface was analyzed by X-ray photoelectron spectroscopy. It is shown that as a result of hydrothermal treatment, Sn4+ ions appear on the surface of zinc oxide nanorods. The study of gas-sensitive characteristics was carried out under the influence of isopropyl alcohol vapors at temperatures of 156°C and 310°C. It is shown that the maximum response at 310°C to 1000 ppm of isopropyl alcohol is 8,24. At the same time, the zinc stannate samples have a fast response of 23 s.
Keywords: .
Yurov V.M., Ibragimova D.A., Portnov V.S., Mausymbayeva A.D.
Nanostructures of rare-earth metals in the coals of the shubarkol deposit — page 736
Abstract: The rare metals of the Shubarkol coal deposit have a surface layer thickness of about 3 nm, i.e. are nanostructures. The thickness of the surface layer of the coal itself is of about 0,2 µm, i.e. it is a mesostructure. The pore radius in the coal substance is 30,6 nm, which corresponds to mesopores, and the specific surface area of coal is 857 m2/g. Rare metals, either in the form of pure impurities (~ 3 nm), or in the form of oxides (~ 7 nm), or in the form of organic impurities (~ 1-3 nm), freely enter into mesopores of the coal. The forms of occurrence of uranium and rare metals in the coals of the Shubarkol deposit indicate that their concentration in the coal is due to the leading role of the hydrogenous mechanism. In the d(I) layer, all rare metals are nanoluminophores, which can be considered as sensitive molecular probes for studying the structure of coal. It is emphasized that the influence of size effects on kinetics of the luminescence decay and anomalous thermalization of rare earths can be easily obtained experimentally. The fractal dimension of Shubarkol coal is 2,60, which is lower than that of anthracite – 2,74. In the mesoporous structure of Shubarkol coal, the adsorption of rare metal impurities is highly developed due to the formation of adsorption layers on the surface of these mesopores, which lead to volumetric filling of these pores by mechanism of the capillary condensation.
Keywords: surface layer, rare metal, nanostructure, mesostructure, atomic volume, size effect, carbon matter, fractal.
5. NANOCHEMISTRY — page 747
Bibanaeva S.A.
Synthesis of aluminosilicate zeolites in the conditions of alumina production — page 747
Abstract: The work is devoted to study of the possibility of obtaining synthetic sodium and calcium aluminosilicates from recycled solutions of alumina production by the hydro-alkaline method. The chemical qualitative and quantitative composition and morphology of zeolites obtained under conditions of high-temperature autoclave leaching have been studied. X-ray phase studies aimed at determining the composition and structure of the obtained aluminosilicate zeolites were carried out. The prospects of the method of the autoclave synthesis of synthetic zeolites with a high yield of the final product with the particle size up to 5 microns are shown. It has been established that the method allows the production of zeolites in parallel with the technological scheme of bauxite processing at an alumina plant, while minimally weighing down the production process. The resulting aluminosilicate zeolite has a wide range of applications in various industries. According to the results of the research, 2 applications for invention patents were filed.
Keywords: circulating solution, zeolite, calcium aluminosilicate, processing, calcium oxide, alumina production.
Blinov A.V., Slyadneva K.S., Gvozdenko A.A., Golik A.B., Taravanov M.A., Nazaretova E.D.
The effect of the mixing rate of the reaction mixture on the dispersed characteristics of the nanoemulsion of fat-soluble vitamin E (alpha-tocopherol acetate) — page 754
Abstract: The article presents the results of a study of the effect of the mixing rate on the dispersed characteristics of nanoemulsions of the fat-soluble vitamin E (alpha-tocopherol acetate). The mixing speed was varied in the range of 3000-22500 rpm. The average hydrodynamic radius of the micelles of fat-soluble vitamin E was considered as an output parameter, which was determined by the method of the dynamic light scattering. It was found that as a result of synthesis, micelles of the fat-soluble vitamin E emulsions are formed, having a monomodal size distribution. The smallest average hydrodynamic radius of the particles was 22 nm. It was found that an increase in the mixing speed from 3000 to 22500 rpm causes a decrease in the average hydrodynamic radius of micelles. The greatest changes are observed at τ = 30 s: a decrease in the average hydrodynamic radius of micelles Rm occurs by 3,3 times (from 210 to 63 nm). It is important to note that an increase in other synthesis parameters also leads to a decrease in the value of the average hydrodynamic radius of micelles of the vitamin E nanoemulsions. By v = 22500 rpm an increase in the mixing time τ from 30 s to 270 s leads to a decrease in Rm by 19 nm (from 63 to 44 nm).
Keywords: fat-soluble vitamin E, nanoemulsion, hydrodynamic radius, mixing speed.
Blinova A.A., Yasnaya M.A., Maglakelidze D.G., Taravanov M.A., Lapin V.A., Leontiev P.S.
Study of the structure and properties of zinc silicate stabilized with L-histidine — page 763
Abstract: This paper presents the results of a study of the process of stabilization of zinc silicate nanoparticles using the amino acid L-histidine. Zinc acetate was used as a precursor, sodium silicate was used as a precipitant, and the amino acid L -histidine acted as a stabilizer. Synthesis was carried out by chemical precipitation in an aqueous medium. A simultaneous thermal analysis was carried out, as a result of which it was found that the addition of an amino acid to nanosized zinc silicate has a great influence on the crystal structure and thermal transitions for this material. Next, the X-ray phase analysis was carried out, which showed that of zinc silicate particles have an amorphous structure and are in a nanoscale state. At the next stage of the work, the process of interaction of an amino acid with a zinc silicate particle was studied by IR spectroscopy. The results of the study showed that stabilization of particles is accompanied by the formation of a chemical bond between silicon in the zinc silicate molecule and the amino group in the L -histidine molecule.
Keywords: nanosized zinc silicate, amino acids, L-histidine, zinc acetate, sodium silicate, phase composition, simultaneous thermal analysis, derivatogram, IR spectroscopy, powder diffractometry.
Bogdanova E.A., Skachkov V.M., Nefedova K.V.
Development of composite mixtures based on hydroxyapatite and biogenic elements for the formation of bioactive coatings — page 771
Abstract: The hardened composite material with a porous structure was obtained by mechanochemical synthesis of nanostructured hydroxyapatite synthesized by precipitation from an aqueous solution with reinforcing additives of zirconium dioxide and silicic acid. Food gelatin is used as a binder. The influence of the phase composition on the physico-chemical properties of coatings (adhesive strength, microhardness, specific surface area, microstructure) is estimated. It has been established that the use of composite material together with gelatin as a part of a bioactive coating makes it possible to increase its hardness and adhesive strength. A patent application has been filed for the developed bioactive coatings based on nanoscale hydroxyapatite and biogenic elements with a binding agent. The composition of the dry mixture based on hydroxyapatite has been developed, which ensures a long shelf life without negative consequences and creates simple transportation conditions. Dilution of the dry mixture with distilled water gives a suspension that is convenient to use for coating implants of any configuration.
Keywords: hydroxyapatite, composite materials, biogenic elements, gelatin, collagen, bioactive coatings, adhesion.
Krut’ko V.K., Doroshenko A.E., Musskaya O.N., Kulak A.I.
Obtaining octacalium phosphate in aqueous medium during the interaction of calcite with monocalcium phosphate monohydrate — page 782
Abstract: Calcium phosphate composite powders consisting of brushite and calcite were obtained in an aqueous medium from a CaCO3/Ca(H2PO4)2 suspension at Ca/P ratios of 1,33, 1,50, 1,67, pH 5–7, and maturation time of 21-50 days. Prolonged maturation (up to 68 days) of composite calcium phosphate powders led to a hydrolytic transition of brushite to octacalcium phosphate, the amount of which increased with increasing duration of the maturation stage. Drying calcium phosphate powders at 37°C for 24 h contributed to the partially transition of the metastable phase of octacalcium phosphate to apatite represented by amorphous calcium phosphate. The presence of vibrations of О–Н at 633 cm-1 as the shoulder on the IR spectra indicates the presence of apatite in calcium phosphate powders. The use of an electric current (20 mA/cm2, 3–20 min) for a local increase of the pH value made it possible to increase the amount of octacalcium phosphate in the composition of the composite powder, which has a characteristic rosette morphology of thin lamellar crystallites.
Keywords: octacalcium phosphate, calcite, monocalcium phosphate monohydrate, brushite, apatite, hydrolytic maturation.
Krut’ko V.K., Maslova L.Yu.., Musskaya O.N., Kulak A.I.
Composites based on calcium phosphate foam ceramic and hydroxyapatite gel — page 791
Abstract: Bioactive calcium phosphate composites were obtained, consisting of open-pore multiphase calcium phosphate foam ceramic based on α / β-tricalcium phosphate, β-calcium pyrophosphate, biomimetic apatite and 5% hydroxyapatite gel at a mass ratio (ceramic foam / hydroxyapatite gel) of 1:3 and 1:10. Preliminary modification of the calcium phosphate foam ceramic with biomimetic apatite in a concentrated SBF×5 solution allows increasing the static strength to 0,05 MPa with a slight decrease in porosity and maintaining the open-pore structure of polyurethane foam. Calcium phosphate composites have increased resorbability in SBF×5 and are resorbed 3–5 times faster compared to calcium phosphate foam ceramic. The presence of a significant amount of hydroxyapatite gel increases the rate of resorption of calcium phosphate foam ceramic and the ongoing processes of apatite formation with the participation of SBF×5 ions due to its high reactivity. The obtained calcium phosphate composites are used in regenerative treatments to fill bone defects in unloaded areas.
Keywords: calcium phosphate foam ceramic, tricalcium phosphate, hydroxyapatite gel, simulated body fluid, biomimetic apatite, resorbability.
Medyankina I.S., Svetlakova K.I., Pasechnik L.A.
Formation of cobalt hydroxosilicate in amorphous silica matrix — page 800
Abstract: The synthesis of cobalt hydroxysilicate Co3(Si2O5)2(OH)2 in a matrix of high dispersity amorphous silica has been proposed. It is shown the formation of a hydroxosilicate, which combines coordinated silica and cobalt-oxygen polyhedrons in the overall structure, as well as the availability of surface hydroxyl groups, contribute to the preservation of a high specific surface area as is in amorphous SiO2. The hydroxosilicate also contributes to the effective manifestation of photocatalytic properties due to the presence of cobalt (2+), which has a high reactivity. As methods of synthesis of SiO2/Сo composites hydrochemical methods are used by impregnation and autoclave treatment with solution of cobalt formate of silica. The influence of the amount of introduced cobalt on the composition, structure, and properties of a composite material containing Co3(Si2O5)2(OH)2 in a SiO2 matrix has been traced. SiO2/Co composites have been tested in the hydroquinone photooxidation reaction when exposed to ultraviolet radiation. The highest degree of hydroquinone decomposition amounting to 84% in 18 hours was achieved for SiO2/Co at a molar ratio of components Co:Si = 0.01:1.
Keywords: amorphous silica, cobalt silicate, hydrothermal synthesis, mechanosynthesis, microstructure, photocatalysis, hydroquinone.
Musskaya O.N., Krut’ko V.K., Kulak A.I., Krutsko E.N.
Modification of fiber cellulose materials with amorphized calcium phosphates and copper nanoparticles — page 811
Abstract: Etherification of the surface of cellulose carriers with phosphoric acid in the presence of urea yielded fiber materials characterized by an increased degree of swelling in aqueous media (by a factor of 1,1-1,5). The copper nanoparticles and their composites with amorphized calcium phosphates were synthesized by the borohydride method using the sodium salt of carboxymethyl cellulose as a stabilizer polymer. The obtained colloidal solutions of copper and their composites with hydroxyapatite are characterized by stability from several days to 2 months. It was found that the modification of cellulose materials (initial and phosphorylated) by the immersion method using aqueous compositions containing amorphized calcium phosphates, copper nanoparticles or composites based on them in the presence of sodium carboxymethylcellulose and ascorbic acid at pH 6 and 11 leads to a decrease in the crystallinity of the polymer carrier. It has been shown by IR spectroscopy that the amorphization of modified fiber cellulose materials is due to a change in the static homogeneity of the system of hydrogen bonds in the polymer structure.
Keywords: cellulose, phosphorylated cellulose, sodium carboxymethylcellulose, amorphized calcium phosphates, hydroxyapatite, copper nanoparticles.
Ostroushko A.A., Zhulanova (Maksimchuk) T.Yu., Kudyukov E.V., Gagarin I.D., Russkikh O.V.
Lanthanum manganite nanopowders synthesis via combustion reactions under the influence of electromagnetic field — page 820
Abstract: Lanthanum manganite doped with strontium samples were synthesized by the combustion method of nitrate-organic precursors of different composition. The combustion process was realized under the influence of an external alternating electromagnetic field and in its absence. It was found that thermochemical generation of charges occurs during precursor’s combustion, recorded as a potential difference of precursor-earth. It is shown that the composition of the initial precursor (organic component and its quantity), as well as the presence of an external alternating electromagnetic field, affect the magnitude of the potential difference that occurs, varying from -7 to 125 V. The relationship between the studied electromagnetic properties (saturation magnetization, coercive force, Curie temperature) of the obtained samples and the precursor–earth potential difference arising during synthesis is shown. The Curie temperature values varied in the range of 38-79°C for samples obtained under the influence of an alternating electro-magnetic field, and 49-104°C in its absence.
Keywords: Complex oxides, lanthanum manganite, synthesis, combustion reactions, charges, electromagnetic field, magnetic properties.
Ostroushko A.A., Menshikov S.Yu.., Rozhentsev D.A., Tkachev N.K., Golub A.Ya.., Tonkushina M.O.
Nanostructured catalysts of the turpentine emulsion polymerization under the influence of potassium persulphate — page 829
Abstract: We have revealed the catalytic activity for initiating the water-emulsion turpentine polymerization of some nanostructured materials such as Keplerate type Mo72Fe30 nanocluster polyoxometalate, nanoporous iron and nanoporous composite of intermetallic compounds Pd2In@Pd3In obtained by dealloying of equiatomic alloys Fe – Mn and Pd – In. For polyoxometalate solutions and nanoporous metal samples, respectively, the yield of sufficiently pure polyterpene resins when using the potassium persulphate initiation depends on the nature of the contact between the catalysts and substrates: solid-liquid-liquid or liquid-liquid. A system that did not contain catalysts was taken as the reaction medium for comparison. Based on the obtained data on the softening point, the molecular weight of the resin samples was determined. Infrared spectroscopy was used to identify the obtained products. In the reaction medium (mainly aqueous) after the isolation of polyterpene resins, chromatographic analysis revealed so valuable products as alpha-terpineol, which is used as an intermediate for obtaining flavors and flotation agents.
Keywords: Nanostructured initiation catalysts, polyoxometalates, metals, emulsion polymerization, turpentine, polyterpene resins, potassium persulfate.
Permiakov N.V., Lebedeva A.I., Maraeva E.V.
Obtainanig and study of the material based on hydroxyapatite and polycaprolactone for extrusion three- dimensional printing — page 838
Abstract: The work is devoted to the search for a scientific and technical solution for the creation of filaments based on hydroxyapatite and polycaprolactone for extrusion three-dimensional printing. Hydroxyapatite powders were obtained by chemical precipitation using microwave radiation, and the average particle size in the powder was determined. Options for creating a filament by extrusion based on a composition of hydroxyapatite and polycaproloctone for subsequent printing of scaffolds (temporary scaffolds necessary for the formation of new functional tissues) are proposed. Images of the surface of calcium hydroxyapatite were obtained using a scanning probe microscope to assess the parameters of surface roughness, which is one of the most important factors for successful cell adhesion to the scaffold surface during osseointegration processes.
Keywords: hydroxyapatite, polycaprolactone, 3D printing, nanocomposite, scaffold, scanning probe microscopy.
Foreword — page 7
1. EXPERIMENTAL STUDIES OF NANOPARTICLES, NANOSYSTEMS, AND NANOMATERIALS — page 8
Bazzal K., Voropay E.S., Alekseenko N.A., Kovalenko M.N., Trinh N.H., Zajogin A.P.
Research of Al2O3 and Al nanopowder formation processes in plasma under the influence of defocused dual laser pulses on aluminum in the air atmosphere — page 8
Abstract: The influence of the magnitude and type of defocusing of twin laser pulses on the purposeful formation of the component and charge composition of laser plasma under the influence of twin laser pulses on a target made of aluminum alloy AD1 (LSS-1 spectrometer) has been studied. It is shown that when defocusing is more than 1 mm, the intensity of the ion line Al III increases several times in comparison with zero defocusing, the intensity of the ion lines Al II, N II also increases more or less monotonously. At the same time, the intensity of the bands AlO practically becomes zero. At the 1 mm defocusing value, the processes of formation of mixed nanopowders were studied and, under the influence of successive series of double laser pulses with the energy of 53 mJ and the inter-pulse interval of the iss on an aluminum target placed in a closed rectangular glass cuvette, the size of primary Al2O3 particles estimated using high-resolution electron microscopy was mainly 30-40 nm, and Al – 45-60 nm. The particles are collected into agglomerates.
Keywords: oxidized nanopowders Al, Al2O3, AlO suboxides, pulsed laser sputtering, laser plasma, laser spark spectrometry.
Bernatskii D.P., Pavlov V.G.
Field desorption of intercalated caesium atoms from graphene on the (100) iridium face — page 18
Abstract: The desorption of caesium atoms from the quasi-spherical carbonized surface of an iridium single crystal was studied using the field desorption microscopy. Field electron and desorption images of the surface during the formation of graphene on the (100) iridium face are obtained. The field electron images of the emitter surface before intercalation and after intercalation of graphene with caesium atoms do not change. The electric field stimulates the desorption of caesium atoms from the intercalated state, due to the breaking of the bonds of the extreme carbon atoms with the surface of the face (100) of iridium. Using frame-by-frame recording, the possibility is shown of observing the localization of graphene layer defects on the surface of the field emitter. It is also shown that the field desorption of caesium atoms from the intercalated state begins with graphene defects located along the perimeter of the graphene island. It is found that desorption centers can be located not only along the perimeter of the graphene island, but also in its central part in the case of the disordered graphene formation.
Keywords: field desorption microscopy, graphene, field emitter, alkali metals, intercalation.
Bernatskii D.P., Pavlov V.G.
Field desorption microscopy of carbon-coated field electron emitters — page 25
Abstract: Field electron emitters in the form of a metal tip with a carbon film on the surface have a number of promising operational properties. The characteristics of the emitter depend on the phase composition, thickness and uniformity of the film. Determining the parameters of films with a thickness of one or more monoatomic layers presents certain difficulties. In this paper, the formation and characteristics of carbon nanostructures on the surface of field emitters made of iridium and rhenium are studied using continuous-mode field desorption microscopy. In the field desorption images, the regions of carbon nanostructures appear as local flashes (avalanche-like desorption). Frame-by-frame analysis of flash video recordings revealed several stages of the flash formation and revealed differences in the desorption from carbon nanostructures on iridium and rhenium. The found differences are explained by formation of the single-layer graphene on iridium and a multilayer graphene on rhenium. Desorption images reveal inhomogeneities and local differences in the film thickness. It is shown that continuous-mode field desorption microscopy makes it possible to determine the regularities of formation of the field desorption images of various carbon nanostructures, in particular, the single-layer and multilayer graphene on the surface of the field emitter, and to diagnose the surface after carburization. Besides, control the uniformity of the resulting coating is possible. The obtained data are useful for developing technology of the effective field electronic emitters.
Keywords: field desorption, carbon, nanostructures, rhenium, iridium, field emitters.
Blinov A.V., Gvozdenko A.A., Blinova A.A., Kobina A.V., Golik A.B., Maglakelidze D.G., Vishnitskaya O.K.
Determination of optimal parameters for synthesis of silver nanoparticles stabilized with polyethylene glycol — page 32
Abstract: Within the framework of this work, the results are presented of a study of the effect of the concentrations of the stabilizer and precursor on the synthesis of silver nanoparticles. Silver nitrate was used as a precursor, and polyethylene glycol with a molecular weight from 200 to 600 Da was used as a stabilizer. The synthesis was carried out by the method of chemical reduction in an aqueous medium. The obtained samples were investigated by photon correlation spectroscopy and spectrophotometry. The presence of a characteristic absorption band at 400 nm in the absorption spectra of all samples of nanosized silver stabilized with polyethylene glycol was established, which is due to the appearance of surface plasmon resonance in metallic silver nanoparticles. It was also found that at the highest and lowest concentration of the stabilizer, equal, respectively, 0,005 and 0,1 mass. %, the formation of large silver particles with an average hydrodynamic radius from 132 to 1900 nm is observed in the reaction system. As a result, the optimal parameters for the synthesis of aggregatively stable silver nanoparticles were determined: the concentration of silver nitrate См(AgNO3)=0,05 M and the concentration of polyethylene glycol equal to 0,01— 0,05 %. Computerquantum-chemical modeling is carried out. It is found that the interaction of the silver atom with the terminal hydroxogroup in the polyethylene glycol molecule in the elementary act of interaction during the stabilization of silver nanoparticles by this polymer is energetically advantageous. This type of interaction is characterized by an absolute chemical hardness equal to η=0,146, and an internal energy of Е=—2048,34 kcal / mol.
Keywords: silver nanoparticles, polyethylene glycol, stabilizer, precursor, spectrophotometry, plasmon resonance, photon correlation spectroscopy, computer quantum chemical modeling.
Bolotov A.N., Novikova O.O.
Viscometry of nanodisperse magnetic liquids and lubricating oils. 1. Instrumentation for rheological studies of magnetic nanodisperse liquid media — page 44
Abstract: Analysis of the literature sources shows that the existing viscometers are not always and not completely able to provide comprehensive studies of magnetic nanofluids for scientific and practical purposes. Design has been developed of a magnetic rotary viscometer which makes it possible to carry out investigations in a wide range of the magnetic field induction. The magnetic field in the device is directed orthogonally to the shear stress and can vary from zero to 1,7·105 A/m. The device has two measuring gaps filled with liquid, that increases the accuracy of the results of studies of low-viscosity liquids. The viscometer allows you to measure the standard characteristics of magnetic nanofluids (viscosity coefficient, plastic viscosity, ultimate shear stress, etc.), as well as to study the structural features of liquids under shear stresses. The shear rate in the liquid can be stably maintained in a wide range of (1÷5) ·103 s-1. The viscosity of the studied liquids can vary from 10-3 Pa·s to ≈ 102 Pa·s. For studies on a viscometer, a small amount of magnetic nanofluid with a volume of about 3,5 cm3 is required. Using experimental data, the mathematical description of the process of laminar fluid flow in the annular gap of the viscometer made it possible to optimize its geometric dimensions and obtain formulas for calculating the viscosity coefficient, shear stress and shear rate.
Keywords: magnetic nanofluid, rheology, coaxial viscometer, shear stress, shear rate, coefficient of viscosity, magnetic field, external and internal friction.
Bolotov A.N., Novikova O.O., Meshkov V.V.
Viscometry of nanodisperse magnetic liquids and lubricating oils. 2. Metrological analysis of a device for rheological studies of magnetic nanodisperse liquid media — page 56
Abstract: An analysis is carried out of the main sources of methodological errors of the magnetic rotary viscometer. The analysis allowed to improve design and to eliminate critical modes of the research. Theoretical evaluations of the systematic error of the device showed that the value of the relative measurement error can be brought to a value of less than 1%. The greatest contribution to the systematic error of the device is made by the instability of the temperature regime of the nanofluid under study and by the inaccuracy of determining the height of the liquid layer in contact with the measuring cylinder. The measurement of the viscosity of the reference liquids on the magnetic viscometer showed that experimental values are slightly, by about 0.9% overestimated. Calibration of the device on various reference liquids allowed reducing the total measurement error down to tenths of a percent. The magnetic rotary viscometer can be used in non-standard scientific studies of the structure and rheological characteristics of nanofluids, for operational control of the processes of synthesis of magnetic liquids and certification of magnetic nanofluids intended for technical use.
Keywords: magnetic nanofluid, rheology, viscometer, shear stress, shear rate.
Bolshakova N.N., Vahterov E.V., Ivanova A.I., Ped`ko B.B., Semenova E.M.
Thermal-induced domain processes in triglycine sulfate crystals with chromium impurities — page 65
Abstract: The article presents the results of studies of thermally induced domain processes in chromium-containing crystals of triglycine sulfate (TGS). It is shown that a change in the temperature of TGS :Cr3+ crystals in the absence of external electric fields is accompanied by a rearrangement of the domain structure, that occurs most intensively in the region of the phase transition. A depolarizing field of ~1,4·105 V·m-1, which is generated by a gradient change in the temperature of the sample, causes the process of switching its domain structure. In unannealed crystals at impurity concentrations exceeding 5·10-3 wt.%, switching processes are hindered, and the intensity of thermally induced domain processes is significantly lower than that for samples with a lower impurity content. The intensity of the switching processes of TGS :Cr3+ crystals is significantly influenced by the rate of their heating. The dependences of the integral number of polarization-reversal jumps on the heating rate of the samples N=f (V) are extreme. The extrema of the N=f (V) curves lie in the rate intervals (0,2—0,8) K·sec-1. The domain structure of TGS :Cr3+ crystals consists of a matrix of the main domain, lenticular and lamellar domains. Evolution of the domain structure is observed under the influence of an electron beam, accompanied by the growth of domains, their coalescence, and sample switching. High-temperature annealing of crystals leads to their polydomenization.
Keywords: triglycine sulfate, domain structure, ligand, switching processes, annealing.
Greshnyakov V.A., Belenkov E.A.
Formation of a novel diamond-like bilayer based on 5-7 graphene — page 76
Abstract: First-principle calculations of the structure and properties of orthorhombic L5-7 graphene and a novel diamond-like bilayer formed on its basis are performed. The calculations using the density functional theory method showed that L5-7 graphene of Stone-Wales defects should exist stably under normal conditions, and its structure should be corrugated in a wave-like manner. Under strong uniaxial compression of bilayer L5-7 graphene, the formation of the novel diamond-like DL5-7 bilayer can occur. The pressure of the «L5-7 → DL5-7» phase transition is 10,1 GPa, when the interlayer distance in bilayer graphene decreases to 1,61 Å. This bilayer has an orthorhombic crystal lattice (pbam) with the parameters a=10,145 Å and b=5,270 Å. The unit cell of the DL5-7 pbam bilayer contains 32 carbon atoms. The bond lengths vary in the range from 1,5590 to 1,6226 Å, while the angles between these bonds range from 89,62 to 140,8 °. The structure of the diamond-like bilayer should be stable up to 270 K. The calculated values of the surface density and the difference total energy of this bilayer relative to the diamond total energy are 1,19·105 g/cm2 and 1,31 eV/atom, respectively. The DL5-7 pbam bilayer should be a semiconductor with a straight bandgap of 1,63 eV.
Keywords: graphene, topological defects, diamond-like layer, ab initio calculations, crystal structure.
Guseva O.S., Malyshkina O.V., Ivanova A.I., Boitsova K.N.
Barium and calcium niobate ceramics: specific features of their structure — page 85
Abstract: We obtained and studied the samples of ceramics based on barium niobate and calcium niobate CaxBa1-xNb2O6 with different percentages of barium and calcium ( x=1 ; 0,9 ; 0,8 ; 0,7 ; 0,6 ; 0,5 ; 0,4; 0,3 ; 0,2; 0,1 and 0). The effect of the sintering temperature on the structure and dielectric properties of ceramics has been investigated. One batch of the samples was sintered at a temperature of 1100°C, the second at 1250°C. We have shown that the sintering temperature of 1100 °C is not enough to obtain good ferroelectric properties, and the process of grain recrystallization is not completed. According to studies of the elemental composition, in samples sintered at a temperature of 1250 °C with the Ca content greater than 0,5, Ba atoms are not present in all grains, which also affects the course of the temperature dependences of the dielectric constant A sample with x=0,3 is distinguished by its dielectric properties.
Keywords: piezoelectric ceramics, barium-calcium niobate, lead-free materials, grain structure, permittivity.
Devitsky O.V., Kravtsov A.A., Sysoev I.A.
Study of the composition of GaAs1-yBiy films obtained by pulsed laser deposition — page 96
Abstract: Uniaxial cold pressing was used to fabricate the GaAs1-yBiy targets with the Bi content of 1 and 22 %. From the obtained targets, pulsed laser deposition of GaAs1-yBiy thin films on the GaAs and Si substrates was carried out for the first time. We studied the composition, Raman and PL spectra of thin GaAs1-yBiy films obtained from targets with 1 and 22 % of Bi . According to the photoluminescence spectra of thin GaAs1-yBiy films on GaAs substrates, it was determined that the maximum content of Bi in the films did not exceed 2,7 %. The results obtained well correlate with the results of the energy dispersive analysis, the composition of films obtained from targets with the Bi content of 1 and 22 % – GaAs0,975Bi0,025 and GaAs0,973Bi0,027 . It was found that the LO (GaBi) phonon mode of associated with disordering during mixing of GaAs and GaBi phases to be at a frequency of 181 cm-1. For the thin film obtained on the Si substrate, the mode LO (GaAs) was observed that was less pronounced and shifted by 3 cm-1 to the left, while the mode TO (GaAs) , forbidden by the selection rules, had a higher intensity and its shift was of about 1 cm-1 relative to the frequency of the mode TO (GaAs) of the thin film obtained on the GaAs substrate.
Keywords: thin films, pulsed laser deposition, GaAs1-yBiy, Raman light scattering, photoluminescence.
Devitskiy O.V.
Roughness and structure of InGaAsN thin films on Si — page 106
Abstract: By the method of pulsed laser deposition in atmosphere of an argon-nitrogen gas mixture, for the first time thin InGaAsN films on GaAs and Si substrates were obtained from the In0,02Ga0,98As target. The In0,02Ga0,98As target was formed by uniaxial pressing from GaAs and InAs powders. The surface morphology and structure of these thin films are studied by atomic force microscopy and X-ray diffraction. It is shown that In0,02Ga0,98As1-yNy films on Si have an average crystal size of 0,93 nm, and In0,02Ga0,98As1-yNy films on GaAs of 0,99 nm. It is determined that a decrease in the pressure of an argon-nitrogen mixture during pulsed laser deposition of thin In0,02Ga0,98As1-yNy films on GaAs and Si substrates leads to a decrease in the value of the root-mean-square roughness of the surface. The smallest root-mean-square roughness equal to 0,25 nm had a thin In0,02Ga0,98As1-yNy film on a GaAs substrate obtained in vacuum, the largest root-mean-square roughness of 19,37 nm had a thin In0,02Ga0,98As1-yNy film on a Si substrate obtained at the argon-nitrogen mixture pressure of 10 Pa -.
Keywords: InGaAsN , pulsed laser deposition, Raman spectra, thin films.
Dyshekova A.Kh.., Karmokov A.M., Khasanov A.I., Kalmykov R.M., Shomakhov Z.V.
Morphology and composition of the interface boundary of sodium chloride single crystals with lead — page 115
Abstract: The interface between liquid lead and sodium chloride after cooling and breaking the contact was investigated by the electron microscopy and X-ray spectral analysis. Accumulation of surface-active impurities, contained both in the bulk of lead and in sodium chloride was found on the fracture surface of the samples. As shown by the results of the X-ray diffraction analysis, the content of impurities on the surface of the sodium chloride substrate exceeds the bulk content by several orders of magnitude. A significant accumulation of silicon and indium impurities is also observed on the lead surface. Anisotropy of spreading of liquid lead over the surface of sodium chloride monocrystals is observed in the studied samples. The separation line of a solidified lead droplet on the surface of sodium chloride with orientation (110) deviates noticeably from a circle. In addition, on the electron microscopic image of the lead interface after detachment from the substrate of sodium chloride of orientation (110), there are areas in the form of a «cigar», in which the accumulation of impurities was detected. The orientation of these regions coincides with the crystallographic direction of the substrate.
Keywords: lead, sodium chloride, electron microscopy, interface, X-ray spectral analysis.
Efremov V.V., Palatnikov M.N., Shcherbina O.B.
Metastable state with high electric conductivity in Li0,12Na0,88Tа0,25Nb0,75O3 synthesized at high pressure — page 123
Abstract: The results are presented of a study of a ferroelectric solid solution Li0,12Na0,88Ta0,25Nb0,75O3 with a perovskite structure based on sodium niobate and synthesized under high pressure and temperature. In the temperature range of 290 — 800 K, the values of the specific conductivity at direct current, the activation energy of charge carriers, and the real part of the dielectric constant were determined by the method of impedance spectroscopy. Evolution of temperature anomalies of specific conductivity and dielectric constant during thermal cycling is shown. The observed effects are associated with structural phase transitions, and the Curie temperature is determined. The Li0,12Na0,88Ta0,25Nb0,75O3 undergoes a second-order phase transition. It was found that a metastable phase is formed in Li0,12Na0,88Ta0,25Nb0,75O3, which has a high electrical conductivity at the room temperature. When heated above the Curie temperature, this phase is destroyed. Possible mechanisms of the discovered phenomena are discussed.
Keywords: impedance spectroscopy, solid solutions based on sodium niobate, high pressure, metastable phase, phase transitions.
Zigert A.D., Dunaeva G.G., Sdobnyakov N.Yu.
Fractal analysis of the maze-like domain structure of ferrite-garnet films in the process of magnetization — page 134
Abstract: In this work, using a set of experimental techniques and specialized software, magnetic bismuth-containing ferrite-garnet films grown on gadolinium-gallium garnet substrates are investigated. The limiting magnetic hysteresis loops are obtained by the method of optical magnetometry for defective and defect-free areas of bismuth-containing ferrite-garnet films. It was found that, far from defects, the loop exhibits a non-coercive behavior within the error limits. For the case of magnetization reversal, a coercive state with HcI ~ 1Oe appears near the defect. For different sections of the limiting magnetic hysteresis loop, the fractal dimension is determined. The obtained values are in the range of DL=1,35÷1,46 for an arbitrary section of the film and DL=1,37÷1,54 for a section with defects. Typical morphological characteristics of the surface of a bismuth-containing ferrite-garnet film have been determined. The results obtained make it possible to predict the relationship between the value of magnetization and the value of fractal dimension for epitaxial bismuth-containing magnetic films of iron garnet.
Keywords: magnetic films, ferrite garnets, bulk defects, domain structure, coercivity, fractal dimension, nanorelief.
Ivanov V.I., Pyachin S.A.
Separation of particles in polydisperse nanosuspension in the laser radiation field — page 146
Abstract: On the basis of a stationary solution of a diffusion equation separation of nanoparticles in a transparent polydisperse aqueous suspension with different types of size distributions was studied under the action of the light pressure arising in the laser radiation field with the intensity of0,5—500 W/cm2. It was found that particles with a radius of more than 100 nm will mainly be precipitated at the bottom of the cell, and the concentration of smaller nanoparticles in the entire volume of the suspension will remain unchanged. In the case of a symmetrical initial distribution of nanoparticles size, the effect of a light beam with high intensity on the suspension leads to a violation of the symmetry of the distribution function curve, as well as a shift of the maximum to the region of smaller particle sizes on the irradiated surface. If the initial size distribution is asymmetric, the initial single-mode particle size distribution is transformed into a two-mode one. This technique can be used to isolate nanoparticles of certain sizes depending on the power density of the radiation.
Keywords: laser radiation, polydisperse medium, nanoparticles, deposition, separation.
Ivanov D.V., Antonov A.S., Semenova E.M., Ivanova A.I., Anofriev V.A., Sdobnyakov N.Yu.
Different schemes for obtaining fractal relief of nanosized platinum films — page 156
Abstract: The morphology of the relief of nanosized platinum films on the mica surface is investigated using the scanning probe (in the atomic force mode) and tunneling microscopy. Platinum films were investigated immediately after their preparation in a magnetron sputtering facility, as well as after annealing in a muffle furnace in an air atmosphere. Annealing made it possible to establish the possible ranges of variation of the fractal dimension and the altitude parameters corresponding to degradation of the nanorelief. The values of the fractal dimension were obtained for films of different thicknesses using two alternative methods of investigation at different initial scales of samples: based on the data of an atomic force microscope – c D=2,17÷2,38 and a scanning tunneling microscope – c D=2,28÷2,50 depending on the sequence of deposition of layers and annealing of films. For comparison, experimental data of other authors are presented. The choice of the sequence of operations for magnetron sputtering and annealing, and external conditions makes it possible to formulate recommendations for development of the technology for «growing» structures with a given surface morphology.
Keywords: scanning probe microscopy, atomic force microscope mode, scanning tunneling microscopy, magnetron sputtering, annealing, nanorelief, roughness parameters, fractal dimension, platinum films.
Ivanova A.I., Zigert A.D., Tretyakov S.A., Semenova E.M., Dilmieva E.T., Karpenkov A.Yu., Barabanova E.V., Sdobnyakov N.Yu.
Micromorphology of the surface of rapidly quenched Heusler-alloys — page 166
Abstract: The paper describes the results of the scanning electronic and atomic force microscopy research of the surface structure of the Ni57Mn21Al22, Ni57Mn21Al19Si3, Ni40Co10Mn34Al16 rapidly quenched ribbons. The influence of the chemical composition on the size, boundary geometry and structure of the grains is considered. It is shown that all the test samples have a nano-sized martensitic relief, and its parameters are determined. It has been established that the cross section of the ribbon is represented by crystalline grains of different shapes which are due to differences in the cooling rates along the edges and in the center of the samples. Elemental mapping of the cross-sectional surface of the ribbons was carried out using an X-ray energy dispersive spectrometer, and a uniform distribution of chemical elements in the samples was established. It is shown that the cobalt doping of Ni57Mn21Al22 ribbon causes changes in the micromorphology of the surface and has a significant effect on the magnetic properties of rapidly quenched ribbons: field dependences of themagnetization and domain structure.
Keywords: Heusler alloys, structural transformation, rapidly quenched ribbons, surface microstructure, martensitic relief.
Ivanova A.I., Marinicheva K.A., Tret’yakov S.A., Ivanov A.M., Molchanov S.V., Kaplunov I.A.
Temperature dependence of optical transmission of germanium single crystals — page 177
Abstract: In this work, we investigated optical transmission in the wavelength range of 2—14 µm of low-resistance germanium crystals (1—3 Ω·cm) doped with donor and acceptor impurities in the temperature range from 86K to 523 K. The values of the attenuation coefficients for investigated crystals are obtained. Minimum attenuation coefficients α of 0,0015—0,0231 cm-1 in the temperature range from 86K to 323K are characteristic for germanium single crystals doped with antimony in the range 2,1—11 μm. Studies have shown that the low values of α and the transmittance τ at a wavelength of 3,39 μm for Ge:Bi and Ge:Sb crystals make it possible to use these low-resistance germanium crystals for gas helium-neon lasers at temperatures from 86K to 323K. The temperature changes in the geometry of the crystal surface are investigated at the nanoscale level. It is shown that heating crystalline germanium leads to an increase in the diffuse reflection of radiation from the surface. The possibility of using the low-resistance germanium crystals doped with antimony as elements of infrared optics in the temperature range 86—373 K has been demonstrated.
Keywords: germanium single crystals, temperature stability, optical transmission, attenuation coefficient, surface nanorelief, diffuse reflection.
Kalmykov R.M., Karmokov A.M., Shomakhov Z.V., Dyshekova A.Kh..
Nanosized structures in PbTe matrix with CdSe impurities — page 187
Abstract: In this work, electron microscopic studies of semiconductor compounds based on PbTe with impurities of dispersed CdSe phases have been carried out. As shown by the research results, in the initial undoped PbTe compound, the content of lead atoms is about 63,8 wt.%, and the tellurium content was 36,2 wt.%, i.e. corresponded to the stoichiometric composition. According to the electron microscope images, these components are evenly distributed over the area. The results of the study also showed that the formed new phases had grain sizes from 90 nm to 2 μm. The obtained values of the lattice parameter for the lead telluride compound and crystal system are in good agreement with the literature data. The structure of the resulting phases has the same symmetry as the initial undoped PbTe compound, a face-centered cubic lattice with the Fm3m symmetry class. In the molecules of the newly formed phases, in which the abundances of the elements Cd and Se prevailed, a change in the crystal lattice syngony was found.
Keywords: lead telluride, cadmium selenide, nanoscale structures, lattice parameter, phase changes.
Kartashynska E.S.
On estimation of the area per a surfactant molecule in a 2D monolayer during the liquid-expanded-liquid-condensed phase transition at the air/water interface — page 196
Abstract: A method is proposed to estimate the area per molecule of a surfactant monolayer Ac at the transition onset of the liquid-expanded to a liquid-condensed phase based on two theoretical models. A thermodynamic model with account for nonideality of the mixing entropy makes it possible to estimate the Gibbs energy of surfactant clusterization using the Π-A isotherms obtained at different temperatures. On the other hand, the quantum-chemical approach also makes it possible to calculate this thermodynamic parameter and assess the structural features of the obtained monolayers. The values of the Gibbs clusterization energies of small surfactant associates and the geometric parameters of the monolayer unit cells were previously calculated using the quantum-chemical semiempirical method PM3 for eight classes of amphiphilic compounds: saturated and ethoxylated alcohols, saturated and cis-monoenic carboxylic acids, α -hydroxylic and α -amino acids, N -acyl-substituted alanines and dialkyl-substituted melamine. These parameters are used in the thermodynamic model with account for nonideality of the mixing entropy to calculate Ac . The estimated values Ac adequately reflect the experimental temperature dependence for the considered phase transition: with an increase in temperature the area per surfactant molecule of a fixed chain length decreases, and vice versa, with an increase in the surfactant chain length at a fixed temperature, the value Ac increases. This makes it possible to use the proposed approach for prognostic purposes.
Keywords: amphiphilic monolayer, clusterization Gibbs’ energy, unit cell, phase transition, thermodynamic model.
Kovalenko M.N., Alekseenko N.A., Markova L.V., Rutkovskaiy L.S., Patapovich M.P., Zajogin A.P.
Studies of processes of the precursor formation for production of CuAl2O4 nanoceramics at the effect of double laser pulses on AD1 and M2 alloys in the air atmosphere — page 209
Abstract: A study of formation of mixed Al nanopowders, copper and aluminum oxides, and precursors for production of CuAlO2 and CuAl2O4 nanoceramics under the influence of double laser pulses with energy of 53 mJ and the interpulse interval of 10 microseconds on a target consisting of plates of aluminum grade AD1 and copper grade M2, 0,4 mm thick, glued together and placed in a closed rectangular glass cuvette. It is found that the successive exposure of a series of double laser beams to an aluminum target and then to a copper target leads to a multiple increase in the yield of AlO suboxides, aluminum and copper ions and atoms in the laser torch, compared with the exposure to single laser pulses. To better understand the hidden mechanisms of this dependence, we study the processes occurring both on the surface and in the near-surface laser plasma inside the resulting microchannel when the target is broken by a series of single and double laser pulses. The possibility of obtaining precursors for the production of nanoceramics such as CuAlO2, CuAl2O4 is shown.
Keywords: oxidized nanopowders Al , Al2O3, AlO suboxides, copper oxides, CuAl2O4, CuAlO2, pulsed laser sputtering, laser plasma, laser spark spectrometry.
Kravtsov A.A., Chikulina I.S., Vakalov D.S., Chapura O.M., Krandievsky S.O., Devitskiy O.V., Lapin V.A.
Luminescence of YAG: Ce doped with silver nanoparticles — page 220
Abstract: This work was the first to study the effect of silver nanoparticles on the luminescence of cerium doped yttrium-aluminum garnet. A sol with the size of silver nanoparticles of ≈100 nm was synthesized using the method of chemical reduction. Phosphor ceramic powder of the yttrium- aluminum garnet doped with cerium was obtained by the two-stage precipitation method. The silver nanoparticles sol was introduced into the precursor powder before calcination in concentrations from 0,125 to 0,1 ml. It was shown that the photoluminescence intensity increased in comparison with the reference when we used this method of introducing silver nanoparticles. The optimal concentration within the study was 0,25 ml. At this concentration, the increase in the photoluminescence intensity at a wavelength of 540 nm was about 10 %. Studies have shown that silver nanoparticles can be successfully used to increase the brightness of the phosphor of the yttrium-aluminum garnet doped with cerium without distortion and deterioration of spectral characteristics.
Keywords: silver nanoparticles, ceramic powder, luminescence, yttrium-aluminum garnet doped with cerium, optical properties.
Krylov A.A., Alekseev V.G., Feofanova M.A., Ivanova A.I., Baranova N.V.
Change in the surface structure of semiconductor polymer films during reverse oxidation-reduction — page 228
Abstract: The surface morphology of films of semiconducting polymers: polyaniline, poly-o-toluidine, poly-naphthylamine was studied by scanning electron microscopy. The films were obtained by electrochemical synthesis from solutions of their monomers acidified with mineral acids by the method of cyclic voltammetry. The films are formed on platinum substrates made according to the principle of bimetallic plates. The processes of reversible oxidation and reduction of the obtained films were carried out using an electric current in aqueous solutions of hydrochloric acid, which led to the doping of polymers with chloride anions. It was shown that the surface of films of polyaniline and poly-o-toluidine has a similar structure, consisting of numerous spherical grains ranging in size from 1 to 5 μm. The surface of poly-α-naphthylamine films is significantly different and consists of dendrons and large pores. In this case, in all cases, the observed supramolecular formations for films in the oxidized state are somewhat larger than for films in the reduced state, which is due to a change in the conformation of macromolecules.
Keywords: .
Kuznetsov Yu.A., Lapushkin M.N.
Electron-stimulated desorption of lithium atoms adsorbed on the surface of gold-lithium intermetallic — page 235
Abstract: A thin film of the intermetallic compound LixAuy was obtained at room temperature by deposition Li atoms onto a layer of adsorbed gold on the tungsten surface. The processes of electron-stimulated desorption of Li atoms from the surface are investigated. It is shown that electron-stimulated desorption of Li atoms can be observed only in the case when at least one monolayer of Li and Au atoms is deposited. The dependence of the electron-stimulated desorption yield of Li atoms on the amount of deposited has a maximum when two monolayers of atoms Li are deposited on Au . The results obtained indicate the LixAuy formation of various stoichiometry: from with a deficit of lithium atoms to the deposition of two monolayers of atoms. In the kinetic energy distribution of desorbed Li atoms, two peaks were found: high-energy and low-energy. The first of them is associated with the desorption of Li atoms from LixAuy , and the second with the desorption of Li atoms from the upper monolayer of Li atoms.
Keywords: electron-stimulated desorption, adsorption, alkali metals, gold, intermetallic compounds.
Kuznetsova Yu.V.
Improving the efficiency of the contact force method of the atomic force spectroscopy — page 243
Abstract: We propose a technique that optimizing the method of contact force spectroscopy. With the help of a macro language integrated into the NOVA software of the Solver P47 scanning probe microscope, an algorithm was developed that allows analyzing force curves without leaving its main interface. The approbation of the method was done on samples of synthesized polymer, since one of the most important mechanical properties determining their range of applications is elasticity. In this paper, local values of the Young’s modulus on the polymer surface are obtained by the method of contact force spectroscopy using the YUNG script developed using a macro language integrated into the control program of a scanning probe microscope. It is shown that the use of the YUNG script makes it possible to optimize the method of contact force spectroscopy by searching for the exponent γ, choosing a model for calculating the interaction force for further determination of the local Young modulus.
Keywords: atomic force microscopy, the method of contact atomic force spectroscopy, Young’s modulus, elastic modulus, Hertz model.
Kuleshov D.S., Blinov A.V., Blinova A.A., Yasnaya M.A., Maglakelidze D.G., Vishnitskaya O.K.
Comparison of the efficiency of different detectors of the scanning electronic microscope « MIRA-LMH» for studying microstructure of nanomaterials — page 250
Abstract: At the first stage, the objects of study were synthesized – silicon dioxide by the Stober method, where tetraethoxysilane was used as a precursor, and a nanocomposite ZnO–Au by the sol-gel method using the aqueous zinc acetate dihydrate as a precursor. At the second stage, the microstructure and morphology of the obtained samples were investigated by scanning electron microscopy on a «MIRA-LMH» scanning electron microscope (Tescan company) using both a classical secondary electron detector and additional detectors – intralens secondary electron detector and back-scattered electrons detector. As a result of the research, it was found that when using the secondary electron detector, practically no noise images with topographic contrast are obtained. When using the intralens secondary electron detector, images of only material contrast are created, without the influence of the surface relief. Also, the use of this detector made it possible to obtain high-quality images with a high resolution at a distance of 5 mm from the sample. When using a back-scattered electrons detector with a working distance to the sample of 8 mm and increasing the resolution of the microscope, the resulting images have low border contrast, but represent compositional information with high sensitivity. Thus, it was found that the intralens secondary electron detector with a working distance of 5 mm to the sample is optimal for obtaining clear images of the microstructure of the surface of nanomaterials at multiple magnifications.
Keywords: silicon dioxide, nanocomposite ZnO—Au , scanning electron microscopy, detectors, microstructure.
Lapin V.A., Kravtsov A.A., Kuleshov D.S., Malyavin F.F.
Investigation of possibility of the misfit dislocation density reduction in Ge / Si films with a buffer layer — page 263
Abstract: The possibility of improving the quality of Ge/ Si heteroepitaxial structures with a buffer layer is investigated. It is shown that when using a preparatory layer consisting of nanostructures overgrown with a low-temperature buffer layer, it is possible to manifest the so-called effect of annihilation of the misfit dislocations in the bulk of the buffer layer Buf , which significantly improves the quality of the resulting structures. The dependence of the morphology of the surface of the pure Ge layer on the buffer on the growth time of nanostructures in the Si /Buf interface is presented. The optimal technological parameters of the growth of nanostructures for obtaining a Ge layer with a minimum roughness value are revealed. The best results were achieved when the deposition time of nanostructures was 2 min. At the same time, the minimum surface roughness value of 78 nm was achieved. It is shown that with a further increase in the size of the nanostructures, the process of annihilation of defects slows down, and the growth of the low-temperature buffer layer is replaced by a three-dimensional island growth, which increases the differences in the relief of the surface of the grown layer.
Keywords: heteroepitaxy, molecular beam epitaxy, misfit dislocations, buffer layer, defect annihilation.
Malashenko V.V., Malashenko T.I.
Specific features of inelastic processes in materials with nanoscale defects — page 272
Abstract: The high strain rate deformation of alloys containing Guinier-Preston zones under high- energy external influences has been theoretically analyzed. The analysis was carried out within the framework of the theory of dynamic interaction of structural defects. The investigated dissipation mechanism consists in the irreversible transfer of energy of an external impact into the energy of dislocation vibrations. An analytical expression for the dynamic yield stress taking into account all structural defects of the alloy has been obtained. It is shown that, under high-energy external influences, nanoscale defects affect the nature of the dependence of mechanical properties on the concentration of atoms of the second component. The dependence of the dynamic yield stress on the atomic concentration of the second component becomes nonmonotonic and has a minimum. Numerical estimates of the concentration corresponding to the minimum yield stress has been made. At this concentration value, a transition occurs from the dominance of the dislocation drag by the Guinier-Preston zones to the dominance of the drag by the atoms of the second component.
Keywords: high strain rate deformation, dislocations, Guinier-Preston zones, point defects, nanomaterials.
Malyshkina O.V., Patsuev K.V., Ivanova A.I., Ali M.
Comparative analysis of the properties of sodium niobate and sodium – lithium niobate ceramics — page 278
Abstract: The authors studied the effect of the temperature of sodium niobate synthesis on the state ofpolarization in c eramic samples of pure sodium niobate and modified with lithium. A comparative study of the structure and pyroelectric properties of the obtained samples has been carried out. It is shown that the introduction of lithium as a modifier leads to a significant change in the structure in the depth of ceramic samples based on sodium niobate. If in the depth of the pure sodium niobate samples, as well as on the surface, there are individual grains, then the central part of the sodium niobate- lithium niobate ceramics is a continuous mass in which individual grains are not observed. In all samples, except for pure sodium niobate, which was synthesized by double synthesis (the first at 650 °C, the second at 700 °C), the existence of a polarization gradient along the thickness of the samples was established. The gradient is directed from the side corresponding to the positive end of the polarization vector to the side corresponding to the negative end of the polarization vector.
Keywords: piezoelectric ceramics, lead-free materials, pyroelectric effect, spontaneous polarization, grain structure.
Mamaev D.V., Merkuryev S.A., Malyshkina O.V.
Pore percentage estimation of piezoelectric ceramics using CCANN and image made with SEM — page 286
Abstract: The authors synthesized samples of piezoelectric potassium sodium niobate ceramics of 10,25 and 40 pore percentage by volume. Capsule convolutional artificial neural network has been developed for estimation of the pore percentage in images. Using the scanning electron microscopy, f learning massive of examples was formed (photographs of surface and edges of so-synthesized samples). Development and approbation of the capsule convolutional artificial neural network was completed in a few stages. During the first stage, the network was trained using a backpropagation method. Secondly, it was tested by a testing set. At the final stage we made a comparison of the acquired results with the results of the density comparing method. The article shows that this method can be used the pore percentage estimation in sodium niobate ceramics because the acquired results are comparable with the results of other methods. It was found that the samples where the pores were not made also have some pore percentage (about 5%).
Keywords: piezoelectric ceramics, capsule convolutional artificial neural network, artificial neural networks, pore percentage.
Maraeva E.V., Moshnikov V.A.
Nitrogen thermal desorption of as a control method for determination of the nanoparticle size in compositions based on zinc oxide and hydroxyapatite — page 294
Abstract: In this paper we consider the possibility of using the nitrogen thermal desorption method for determining the size of nanoparticles in compositions based on hydroxyapatite and zinc oxide. The compositions in the form of tablets were obtained using a manual water press. The initial powders of hydroxyapatite were obtained by chemical deposition using a microwave radiation. Using the BET sorption method, the specific surface area of the powders is analyzed before and after pressing, and the effect of the composition formulation on the specific surface area is investigated. The calculation of the average sizes of nanoparticles in composites is given on the basis of the results of sorption measurements within the framework of the models of spherical and rod-like nanoparticles. The field of application of the materials under consideration is medicine, including the use of nanocomposites in targeted drug delivery and in bone engineering as bioactive coatings applied to the surface of a metal bioimplant.
Keywords: hydroxyapatite, zinc oxide, adsorption, specific surface area.
Matveev A.V., Mashukov M.Y., Nartova A.V., Sankova N.N., Okunev A.G.
Automatic analysis of microscopy images using the DLgram01 cloud service — page 300
Abstract: The study of materials by microscopy often includes counting the number of observed objects and determining their statistical parameters, for which it is necessary to measure hundreds of objects. The created DLgram01 cloud service allows specialists in the field of materials science who do not have programming skills to perform automated image processing – to determine the number and parameters (area, size) of the objects under study. The service is developed using the latest achievements in the field of deep machine learning. To train a neural network, the user needs to label only several objects. The neural network is trained automatically in a few minutes. Important features of the DLgram01 service are the ability to adjust the results of neural network prediction, as well as obtaining detailed information about all recognized objects. Using the service allows to significantly decrease the time for quantitative image analysis, reduce the influence of the subjective factor, increase the accuracy of the analysis and its ergo-intensity.
Keywords: microscopy, recognition, nanoparticles, deep neural networks, artificial intelligence.
Muratova E.N.
Thermal studies of porous aluminum oxide membranes — page 312
Abstract: Study of optical properties of nanoscale membranes of porous anodic alumina can significantly expand the scope of this material. The paper presents the results of thermal imaging studies of porous anodic alumina membranes with various structural parameters. Temperature distribution profiles for membranes obtained in various electrolytes based on sulfuric, oxalic and orthophosphoric acids have been constructed. It was found that the shielding of IR radiation is more pronounced (approximately 30 %) in membranes with a smaller pore diameter ds pore≈20 nm compared to membranes with a larger pore diameter dl pore≈200 nm. This is due to the scattering of thermal radiation on structural inhomogeneities, which are much higher in porous anodic aluminamembranes obtained with sulfuric acid. Small-diameter pores, under-etched areas and defects act assources of inhomogeneity. Also, due to the increased activity of sulfuric acid in comparison with other acids used, more anions are incorporated into the structure of the sample.
Keywords: porous aluminum oxide, membranes, pore diameter, optical properties, thermal imager, IR radiation.
Musskaya O.N., Krut’ko V.K., Kulak A.I., Krutsko E.N.
Composites based on calcium phosphates and copper nanoparticles — page 320
Abstract: Copper nanoparticles were synthesized by the borohydride method using polymer stabilizers (polyethylene glycol, polyvinylpyrrolidone). It was found by optical spectroscopy that copper nanoparticles obtained at a molar ratio Cu / polymer of 1:(3–6) have the highest stability (up to 1.5 months). It was shown that in the absence of polymer or at its low content (molar ratio Cu / polymer 1 : 1), the resulting nanoparticles aggregate and a precipitate forms containing copper and its oxides (Cu2O , CuO). By mechanical mixing of amorphized calcium phosphates (in powder and gel form) and copper nanoparticles (in the form of a colloidal solution), a powder composite containing Ca19Cu2H2(PO4)14 and Cu2PO4OH phases was obtained. It was shown that during the co-precipitation of calcium phosphates and copper nanoparticles, copper ions are incorporated into the crystal lattice of calcium phosphates with the formation of mixed acidic and medium salts.
Keywords: amorphized calcium phosphates, hydroxyapatite, copper nanoparticles, polyvinylpyrrolidone, polyethylene glycol, composites.
Mustafaev G.A., Mustafaev A.G., Cherkesova N.V.
Charge distribution in the Al2O3-SiO2 system exposed to ionizing radiation — page 329
Abstract: Metal-insulator-semiconductor (MIS) structures are key elements of modern electronic technology, including devices operating under conditions of exposure to penetrating radiation. One of the possible approaches to reducing radiation effects in MIS structures is the use of dielectrics, which reduce the generation and accumulation of excess space charge in the bulk of the dielectric. We investigated the system of dielectrics Al2O3–SiO2. The study shows the suitability of using MIS structures based on a system of dielectrics for formation of devices with high radiation resistance. Applying a Al2O3 layer on top of the SiO2 layer improves the performance of MIS structures by increasing the uniformity of parameters. The main effect of the influence of the Al2O3 layer on the parameters of the structures is to reduce the mechanical stresses at the interface SiO2 -substrate. The trapping of electrons in Al2O3 , compensates for the charge of the trapped holes in SiO2 , and reduces the parasitic current through Al2O3.
Keywords: ionizing radiation, surface states, charge distribution, system of dielectrics, radiation resistance.
Permiakov N.V.
The use of liquid probes based on an eutectic solution for studying the conducting properties of thin films — page 338
Abstract: The work is devoted to development of a modular four-probe setup using a liquid contact based on an indium-gallium eutectic solution ( EGaIn), which can be used to create clamping liquid contacts that do not introduce mechanical deformation into the measured structures. It is proposed to use this setup for measuring the current-voltage characteristics of thin-film samples. A modular measurement scheme is assumed. Each probe is driven by four motors to position and expel a drop from the syringe to form the desired contact area size. Optical control is used to prepare the probes and measure the diameter of the formed contact areas. The parameters for the manufacture of liquid probes are selected, namely, the speed of extrusion and movement of the probe along the vertical axis to form a conical droplet. The installation is controlled in the LabView environment.
Keywords: indium-gallium eutectic, electric probe, adjustable contact area size, thin films, current- voltage characteristic.
Polukhin V.A., Belyakova R.M., Kurbanova E.D.
Influence of alloying Ti, Mo and W on the kinetic and strength characteristics of membrane alloys based on Nb and V — page 345
Abstract: An analysis was carried out of influence of , Ti Mo and W on the nature of the amorphous nano- and crystalline structures on the strength and kinetic characteristics – diffusion D and permeability Φ of hydrogen in membrane alloys based on binary Nb – Ni and V – Ni . Doping with Nb – V alloys by titanium, molybdenum and tungsten leads to the gradual replacement of niobium and vanadium, and promotes the formation of several minor phases while acting as barriers for hydrogen diffusion, but contributing hydride reduction processes. A close dependence of the hydrogen kinetics was revealed not only on thermodynamic parameters – temperature and pressure, but also on the presence of free volume in the formed amorphous, nanocrystalline and crystalline alloys. So, the processes of selectivity, the dynamics of hydrogen – its flux J determined by the product of diffusion D and permeability Φ, J = D × Φ depend on the basic composition and the choice of alloying elements (Ti, Mo and W), as well as the formed structures – amorphous, nanocrystalline and duplex, represented by multiphase crystalline microstructures. It was found that a carefully selected composition determines the productivity of the selective process and promotes the release of high-purity hydrogen with its subsequent applications for green energy.
Keywords: hydrogen, amorphous and nanocrystalline alloys, V, Ni, Ti, Zr, Nb, structuring, selectivity, solubility, permeability, diffusion, hydrides, accumulation, thermal stability, fragility, crystallization, modeling, icosahedral clusters, nanophases, duplex structure, Laves phases..
Sverdlik G.I., Ataeva A.Yu., Ataev A.R., Khadzaragova E.A., Vazieva L.T.
Analysis of methods for studying the size of nanoparticles — page 358
Abstract: In the presented work, various methods for determining the size of nanoparticles are considered. An effective method for finding possible options has been determined. Information on various methods and studies was selected and analyzed. Fundamentally different methods for finding the sizes of nanoparticles are considered. Non-contact (optical) methods are the most promising. The particle size ranges of the investigated particles are analyzed and presented using the next methods: optical microscopy, electron microscopy, scanning probe microscopy. The principles of operation and possible schemes of installations for studying the material under study are described. The sedimentation method, using centrifugation and the X-ray principle of detection, is described in more detail. Its advantages over other methods are noted. Examples are given of its use in an experimental setup that allows obtaining differential and integral characteristics in various bases, which make it possible to analyze the particle size distribution in the granulometric study of materials, including nanomaterials.
Keywords: nanoparticles, sedimentation method, sedimentometer, gravity sedimentation, centrifugation, differential and integral curves.
Semenova E.M., Lyakhova M.B., Sinkevich A.I., Ivanov D.V., Antonov A.S., Sdobnyakov N.Yu.
Fractal analysis of the nanostructure of a heterogeneous high coercity alloy — page 368
Abstract: The atomic force microscopy was used to obtain images of the nanostructure of components of a heterogeneous intermetallic SmCoCuFeZr compound in a highly coercive state. At the microlevel, two types of regions were distinguished in the alloys, differing in integral elemental composition and coercivity intervals. Based on the atomic force microscopy data, an analysis of the fractal characteristics of the surface is carried out on both of the above types of areas. It is shown that the fractal dimension of the nanostructure correlates with the local coercivity of the phase components. The phase component with a relatively low coercivity demonstrates the possibility of the existence of structures with fractal dimensions in the 2,396–2,475 range corresponding to a moderately developed fractal relief. In this case, the high-coercive component with a regular nanostructure is characterized by a higher fractal dimension of 2,452–2,508, and in some areas of the sample there were regions with a fractal dimension up to the value of 2,577.
Keywords: atomic force microscopу, nanorelief, nanostructure, surface morphology, coercivity, fractal dimension.
Sidorov N.V., Teplyakova N.A., Palatnikov M.N.
Hydrogen bonds in lithium niobate crystals of different composition — page 376
Abstract: An analysis of complex defects was carried out by IR-spectroscopy method in the area of OH– groups stretching vibrations. The defects are caused by hydrogen bonds present in the structure of nominally pure congruent lithium niobate crystals, crystals of stoichiometric composition with a different Li /Nb ratio, as well as in LiNbO3:Zn(0,04–6,5 мол.% ZnO) crystals doped in a wide range of concentrations due to direct doping of the melt method. Dopants were determined to influence OH– groups concentration, type and localization of complex defects in the crystals structure. A change in the amount of hydrogen sites in the LiNbO3 crystals structure was shown to evaluate the composition either stoichiometric or congruent. The character of OH– groups complexing with cation sublattice point defects was shown to change when doped crystals LiNbO3:Zn(0,04–6,5 мол.% ZnO) trespass concentration thresholds. Dopant incorporation mechanism changes at this drastically, thus crystal properties also change quite sharply. Frequencies (as well as quasi-elastic constants of OH– bonds) change in congruent and doped crystals due to a difference in electronegativities and ionic radii of the main and dopant cations.
Keywords: single crystal, lithium niobate, defects, IR absorption spectra, doping, stretching vibrations of OH– group.
Sidorov N.V., Teplyakova N.A., Palatnikov M.N.
Influence of the method of doping on uniformity and optical properties of LiNbO3:Mg crystals — page 383
Abstract: The paper considers results for strongly doped turned to a single domain state crystals LiNbO3: Mg(5,03 mol % MgO and LiNbO3:Mg ( 4,75 mol % MgO ). Magnesium concentration in these crystals is close to each other and to threshold ≈5 mol % MgO . Crystals were grown from a charge synthesized using precursor LiNbO3:Mg (homogeneous doping method) and from a charge obtained at a direct addition of magnesium to the charge (direct doping method). Complex studies were carried out by Raman spectroscopy and laser conoscopy. Compositional homogeneity and some optical properties of studied crystals are considered. Homogeneous doping with precursor Nb2O5:Mg method allows us to obtain heavily doped LiNbO3:Mg single crystals with low coercive field and more compositionally homogeneous than method of direct melt doping with magnesium. In this case, a more uniform distribution of the dopant in homogeneously doped crystals begins to form at the stage of Nb2O5:Mg precursor synthesis during the formation of chemically active complexes that predominantly determine the oxygen-octahedral structure of the Nb2O5:Mg precursor.
Keywords: lithium niobate crystal, homogeneous and direct doping, Raman scattering, laser conoscopy.
Skachkov V.M., Pasechnik L.A., Medyankina I.S., Sabirzyanov N.A.
Study of the properties of diffusion-hardening composite solders modified with a Ti – Mo powder mixture — page 392
Abstract: The article discusses the possibility of regulating the properties of diffusion-hardening solder based on low-melted gallium-tin, gallium-indium-tin, gallium-tin-zinc alloys and a solid component consisting of a copper-tin alloy powder by introducing a mixture of inert powders of metallic titanium and molybdenum after the heat treatment at various temperatures. The microhardness and thermal stability of composite diffusion-hardening solders are evaluated. It is shown that the heat treatment at higher temperatures contributes to the transition of the solder to an equilibrium state, while a sharp increase in hardness occurs. The phases formed as a result of diffusion hardening were determined by the method of X-ray phase analysis. It is shown that at different processing temperatures, different phases are formed – nanoscale intermetallic compounds. Due to small additives of fillers that are inert or weakly interacting with gallium, but are well wetted by it, the characteristics of the diffusion-hardening solder are significantly improved.
Keywords: composite diffusion-hardening solders, metal powder, properties, microhardness, differential thermal analysis.
Staritsyn M.V., Fedoseev M.L., Kaptelov E.Yu., Senkevich S.V., Pronin I.P.
Structure changing of submicron PZT films with a fine variation of the composition corresponding to morphotropic phase boundary — page 400
Abstract: The paper discusses the possibility of a fine variation in the composition of submicron ferroelectric films of lead zirconate titanate solid solutions corresponding to a morphotropic phase boundary. Composition was varied by changing the distance from the target to the substrate in the range of 30–70 mm in an installation for radio-frequency magnetron sputtering of a ceramic target, in which films deposition occurred on a «cold» platinized silicon substrate. This made it possible to change the composition of the deposited films (i.e., the elemental ratio of Zr and Ti atoms) in the range of 0–1,5 % while maintaining the single-phase perovskite films annealed at 580 °С. In this case, the films were characterized by elemental inhomogeneity of the composition over the thickness, reaching several percents. The thickness of thin lead zirconate titanate layers was 500 nm. Changes in the microstructure and crystal lattice parameters were studied. The change in the composition of the films was accompanied by significant changes in the nature of the spherulite microstructure and growth texture. A sharp jump in the quasi-cubic crystal lattice parameter was discovered, which may be caused by the phase transformation of the ferroelectric phase – from the rhombohedral modification to the two-phase state, presumably consisting of monoclinic and tetragonal modifications.
Keywords: lead zirconate titanate solid solutions, thin films, morphotropic phase boundary, fine variation in composition, microstructure.
Starodub O.S., Voskresenskij V.M., Sidorov N.V., Palatnikov M.N.
Comparative analysis of the influence of doping ions of yttrium and boron formation of defects in lithium niobate crystals — page 411
Abstract: Lithium niobate crystals, which are a widely used and highly demanded as nonlinear optical material, are remarkable for their ability to vary a wide range of ferroelectric and nonlinear optical characteristics depending on the type and concentration of the impurity ion, as well as on the Li/Nb ratio. Based on our approach to modeling clusters in the lithium niobate crystal, in which the cluster grows not by unit cells, but by oxygen octahedra, we have carried out a comparative analysis of the features of the incorporation of impurity ions of yttrium and boron with the same charge +3 into the crystal. It is shown that due to the different ionic radii the incorporation proceeds by to two mechanisms. If for yttrium the usual mechanism operates, when the impurity ion is localized inside the oxygen octahedron. The ion of boron, i.e. a nonmetallic element, is incorporated into the tetrahedral voids of the structure, namely, into the oxygen planes forming the octahedron. In this case, the influence of these impurity ions on one of the most important characteristics of lithium niobate turns out to be diametrically opposite: yttrium enhances the photorefractive effect, boron decreases it, which must be taken into account in the direction of targeted use of lithium niobate crystals.
Keywords: lithium niobate, modeling, clusters, vacancy models, sublattice defects, single crystals, ferroelectrics.
Khubolov B.M.
Physico-chemical properties of electrochromic complex tungsten oxides — page 421
Abstract: A brief review of the problem of electrochromism in disordered thin films of complex tungsten oxides is given on the basis of experimental results published earlier. The problems of the ion- electron ordering in complex tungsten oxides MxWO3(M=Na or K and x=0,3) are regarded as well as their relationship with the dynamics of the process of electrochromic coloring in these condensed systems. Possible ways of solving the indicated problems are considered. The starting point of our campaign to study the electrochromism and to develop the physical grounds of the technology of electrochromic devices was the rejection of the generally accepted electrochemical consideration of this phenomenon. We are convinced that the electrochromic effect is a purely solid-state one occurring in a condensed system with a strong electron correlation. The electronic structure of a solid at the solid- electrolyte interface largely controls the nature and rate of reactions that take place on its surface. In the case of oxides, the role played by the electronic structure is particularly complex. All of the above indicates the need to consider the effect of deep levels in the bulk of the oxide tungsten bronze and on its surface, bordering the electrolyte, on the process of electrochromic coloring.
Keywords: complex tungsten oxides, electrochromic effect, tungsten oxide bronze, thin film, monocrystal.
Khubolov B.M.
Optical properties of amorphous thin films of sodium-tungsten oxide bronzes — page 430
Abstract: The spectral dependences were measured of the optical density of amorphous thin films of sodium-tungsten oxide bronze of the tetragonal structure and the composition Na0,3WO3, condensed on glass substrates, thermostated at temperatures of 373, 473 and 573K, as well as annealed in air vacuum, and electrochromically colored. The optical density D , which is proportional, as is known, to the absorption coefficient, was chosen as the studied optical characteristic. Spectral measurements of films deposited on substrates in the temperature range of 373, 473 and 573K showed the same type of spectral characteristics, with a peak of the exciton absorption in the near ultraviolet. The band of minimum absorption lies in the wavelength range of 400÷460 nm, while that of the impurity absorption is a wide band in the region of 650÷1000 nm with a maximum in the range of 900÷1000 nm. This spectral characteristic determines the blue-blue color of a thin film in transmission. The study of the optical properties of thin films of sodium-tungsten bronzes is an urgent problem.
Keywords: sodium tungsten bronze, thin film, monocrystal, electrochromic effect, optical density, spectral characteristics.
Shebzukhova I.G., Aref`eva L.P.
Influence of polymorphic transformations on anisotropy of the surface energy and the work function of the electron of lithium — page 439
Abstract: On the basis of the electronic-statistical method, a relationship is obtained and the surface energy and the work function of the electron of the faces of lithium crystals are estimated, taking into account the dispersion, polarization, and oscillatory interactions of the atoms of the surface layer. It was assumed that the crystal lattice has no defects. The expressions for the corrections and an analytical relationship between the work function of the electron and the surface energy are modified taking into account the type of the crystal lattice and the orientation of the faces. The work function of the electron and the surface energy of smooth faces are calculated at the limiting temperatures of the existence of polymorphic lithium phases. The influence of polymorphic transformations and temperature on the anisotropy is established. The temperature coefficient of the work function of an electron in a defect-free crystal is positive and amounts to about 0,1–1 meV. The calculation results are in good agreement with the experimental data for polycrystals.
Keywords: work function of an electron, surface energy, lithium, polymorphism.
Shomakhov Z.V., Nalimova S.S., Kalmykov R.M., Aubekerov K., Moshnikov V.A.
Study of the microstructure and composition of tin dioxide layers modified by silver nanoparticles — page 447
Abstract: Tin dioxide layers were synthesized by hydrothermal method from an aqueous solution of SnF2 . Silver nanoparticles were deposited on the surface of the obtained layers by the photoreduction method. The surface morphology of the samples was studied by atomic force microscopy. The size of the silver nanoparticles depends on the concentration of the AgNO3 solution used for the photoreduction reaction. When synthesized from 0,02 M solution with a concentration of, the size of the nanoparticles varies from 10 to 100 nm, when the concentration of the solution is doubled, the size of the nanoparticles is about 100 nm. The surface composition of the layers before and after the deposition of silver nanoparticles was studied using the X-ray photoelectron spectroscopy. It was shown that a layer of the tin dioxide is formed without external inclusions, and metallic silver is deposited. The chemical shift of the peaks of tin and oxygen after the deposition of silver nanoparticles indicates the exchange of electrons between tin and silver. The synthesized layers are of interest for application in the field of semiconductor adsorption gas sensors.
Keywords: tin dioxide, silver nanoparticles, gas sensors, atomic force microscopy, X-ray photoelectron spectroscopy.
2. THE THEORY OF NANOSYSTEMS — page 457
Izmailov V.V., Novoselova M.V.
Correlation-spectral analysis of the topography of engineering surfaces at the nanoscale level — page 457
Abstract: The nanotopography of some typical technical surfaces is investigated and the characteristics of the nanoroughness profile as a random process are experimentally determined – the autocorrelation function and spectral density. It is shown that for the investigated surfaces, their profilograms can be considered as realizations of a random stationary normal ergodic process. A visual check of the process normality was carried out by comparing the experimental values of the profile ordinates with theoretical values obeying the normal distribution, as well as by comparing the frequency polygon with the theoretical probability density function of the normal distribution. Quantitative confirmation of the process normality was carried out using the Kolmogorov goodness-of-fit test. It is shown that at the significance level p=0,05, the hypothesis about the normality of a random process (surface nanoroughness profile) does not contradict the experimental results. The correlation intervals of the considered processes are determined. The form of the autocorrelation functions and the values of the correlation intervals indicate the random nature of the surface profile: in the interval equal to one or two average values of the step of the irregularities of the profile, its ordinates become practically uncorrelated. Spectral density plots indicate that the surface profile can be considered as a wide-band random noise with a predominance of low-frequency components.
Keywords: surface, nanotopography, profile method, random process, normal distribution, autocorrelation function, spectral density, correlation interval.
Kramynin S.P.
Influence of size and pressure on the temperature dependencies of thermodynamic properties of platinum — page 465
Abstract: Based on the parameters of the pair interatomic interaction potential of the Mie-Lennard- Jones for Pt , and using the RP-model of the nanocrystal, the temperature, pressure and size dependencies of the following properties are studied: elastic modulus, thermal expansion coefficient, isobaric heat capacity, and surface energy. The calculation of the equation of state showed good agreement with experiment. The equation of state was calculated along five isotherms: T=300, 1300, 1500 , 1700 , 1900 K. For the first time, calculations of the temperature dependences of the above properties of Pt in the range from 0 to 1500 K along 0 and 50 GPa isobars were performed from a unified standpoint. Calculations of these dependencies were carried out for both macro- and cubic nanocrystals of 306 atoms. It is shown that with an isobaric-isothermal decrease in the nanocrystal size, the values of the elastic modulus and surface energy decrease, while the values of the thermal expansion coefficient and isobaric heat capacity increase over the investigated temperature range.
Keywords: platinum, nanocrystal, size dependencies, equation of state, surface energy.
Kuznetsov Yu.A., Lapushkin M.N.
Calculation of electronic structure of 2D NaAu intermetallic layers — page 475
Abstract: The calculation of the density of states of various thicknesses of the 2D -layers of the intermetallic compound has been carried out. 2D -layers of intermetallic compound NaAu are simulated by supercells NaAu (111) 2×2×2. For a monolayer 2D -layer of an intermetallic compound NaAu the presence of a bandgap with a width of 1,87 eV has been established. An increase in the thickness of the 2D -layers of the intermetallic compound NaAu to two monolayers showed a decrease in the bandgap to 0,81 eV. A further increase in the thickness of the 2D -layers of the intermetallic compound NaAu leads to the disappearance of the band gap, which indicates a semiconductor-metal transition for the 2D -layer of the intermetallic compound NaAu with a thickness of three monolayers. The valence band of the 2D -layer of the intermetallic compound NaAu is formed mainly by Au 5d electrons, with an insignificant contribution from Au 6s and Au 6p electrons. The conduction band of NaAu is formed mainly by Au 6p electrons with an insignificant contribution of electrons Na 3s .
Keywords: electronic structure, intermetallic compounds, 2D -layer, sodium auride.
Malyshkin Yu.A.
Preferential attachment with fitness dependent choice — page 483
Abstract: We study the asymptotic behavior of the maximum degree in the preferential attachment tree model with a choice based on both the degree and fitness of a vertex. The preferential attachment models are natural models for complex networks (like neural networks, etc.) and constructed in the following recursive way. To each vertex is assigned a parameter that is called a fitness of a vertex. We start from two vertices and an edge between them. On each step, we consider a sample with repetition of d vertices, chosen with probabilities proportional to their degrees plus some parameter β>-1. Then we add a new vertex and draw an edge from it to the vertex from the sample with the highest product of fitness and degree. We prove that the maximum degree, dependent on parameters of the model, could exhibit three types of asymptotic behavior: sublinear, linear, and of n / lnn order, where n is the number of edges in the graph.
Keywords: complex networks, random graphs, preferential attachment, power of choice, fitness.
Myasnichenko V.S., Matrenin P.V., Sdobnyakov N.Yu.
Prediction of bonding energy by structural descriptors of metal nanoalloys — page 495
Abstract: The problem of predicting the binding energy for ternary metal nanoparticles and the construction of learning models based on structural descriptors are discussed. Regression dependences of the specific interatomic bond energy were constructed for the ternary Au–Ag–Cu nanosystem. A number of five radial features were used, depending on the pairwise interatomic distance of the nanoparticle structure descriptors. For a more correct assessment of the accuracy, cross-validation was applied, then the results obtained on the validation parts of the sample were averaged. The resulting model limitedly predicts the value of the specific interatomic binding energy within a group of data for nanoparticles of the same composition. For the entire sample the average error in modulus is 14 %. In this case, the model almost accurately determines the composition of a nanoparticle of several variants. The largest value of the coefficient of determination in the entire sample was obtained using an ensemble random forest algorithm. A negative correlation was found between the binding energy of the nanoalloy and the position of the first peak of the radial distribution function for copper atoms.
Keywords: machine learning, radial distribution function, structural descriptor, bond energy, ternary alloy..
Samsonov V.M., Talyzin I.V., Puitov V.V., Vasilyev S.A.
To the problem of applicability of the Tamman temperature concept to nanosized objects: to the 160th anniversary of Gustav Tamman — page 503
Abstract: The introduction provides a brief critical review of the available definitions and interpretations of the Tamman temperature, usually defined as TT(∞)=0,5Tm(∞), and of the Hüttig temperature TH(∞)=0,5Tm(∞) where Tm(∞) is the macroscopic value of the melting point of the material. For a nanoparticle we propose to replace in the above relations Tm(∞) by the melting temperature of the small object Tm , i.e. to define TT as 0,5Tm and TH as 0,3Tm. In our molecular dynamics experiments on Au nanoparticles, carried out using the LAMMPS program, we found that at the temperature T=TT, in both the central part of the fcc nanoparticle (the core) and in its surface layer (the shell), some local species of a quasicrystalline structure appear which are alternately identified either as crystalline or as non-crystalline by the OVITO program. However, contrary to opinion of E. Rukenstein (1984), at T=TT, a liquid layer on the surface of the crystalline nanoparticle is not formed yet. However, a liquid-like layer was gradually developed in the course of the further temperature elevation. At the same time, in our molecular dynamics experiments we did not reveal any manifestation of the Hüttig temperature TH in the structure of crystalline Au nanoparticles reproduced in our molecular dynamics experiments. It is also of interest that in our molecular dynamics experiments the nanoparticle sintering took place not only above the Tammann temperature but below it as well.
Keywords: Tamman temperature, Hüttig temperature, metal nanoparticles, surface melting, sintering, molecular dynamics.
Skobin M.I., Feofanova M.A., Kryukov T.V.
Theoretical and experimental study of macromolecular nanostructures based on heparin and lanthanoids — page 513
Abstract: Study of synthetic and natural materials suitable for the creation of nanocarriers and their modification will provide a breakthrough in the treatment of many diseases. Glycosaminoglycans (heparin and its derivatives) are a good choice for creating nanocarriers due to their unique biological and physicochemical properties. The complexation of Pr (III), Sm (III), Eu (III) with heparin anions was studied by potentiometric titration at 37 °C and an ionic strength of 0,15 M NaCl . Significant forms and chemical equilibria were determined using the NewDALSFEK program. In the pH range from 2,7 to 5 , a complex of the type {[LnHep]}n, is formed, where Hep3- is a monomeric unit of the heparin macromolecule. Data on the stability of nanocompositions were obtained: lgβ [PrHep]=4,27±0,04, lgβ [SmHep]=4,28±0,04, lgβ [EuHep]=4,28±0,03. The M06-HF method in combination with the CSDZ+* basic set was used to perform quantum chemical modeling of the complexes.
Keywords: heparin, lanthanides, stability constant, quantum chemical calculation, anticoagulants, Hartree-Fock method.
Yurov V.M., Goncharenko V.I., Oleshko V.S., Guchenko S.A.
Surface layer thickness and anisotropy of the surface energy of cubic ruthenium crystals — page 522
Abstract: The paper deals with the anisotropy of the surface layer and the anisotropy of the free surface energy of cubic ruthenium crystals. This consideration is based on an empirical model of atomically smooth crystals, the thickness of the surface layer of which depends on single fundamental parameter – the atomic volume of an element. Calculations of ruthenium crystals showed that the thickness of the surface layer of ruthenium crystals in all directions does not exceed d(I)<10 nm and they represent a nanostructure. Crystals of ruthenium aluminum, ruthenium hafnium, ruthenium titanium, ruthenium zirconium have σ>3 J/m2 in the (100) direction. We have considered the problem of gas diffusion in a nanometer ruthenium plate. In contrast to the classical problem, a logarithmic term appears in the resulting equation. This leads to divergence at the origin. Therefore, the boundary conditions must be specified not at x=0, but at x=d(0) – the de Broglie wavelength of electrons. Only in this case the classical diffusion equations are meaningful. It is also important that, according to the obtained equation, the diffusion of the nanoplate depends both on the material of the plate through the diffusion coefficient of the bulk sample and on the size factor. In the classical case, there is no such dependence. Various models have been proposed to describe phase transitions in nanostructures, among which we can mention the Landau mean field method, in which the order parameter is used. We will use Landau’s theory, replacing the temperature T with the coordinate h .
Keywords: surface layer, nanostructure, surface energy, atomic volume, size effect, ruthenium.
3. FIRST PRINCIPLES AND ATOMISTIC MODELING — page 534
Alekseev V.G., Baburkin P.O., Tung S., Komarov P.V.
Computer simulation of π – π interactions of tetrathiophene molecules — page 534
Abstract: The properties of the supramolecular organization of conjugated polymers strongly affect the mobility of charge carriers and, consequently, the properties of produced electronic devices based on them. Therefore, it is important to learn how to build computational models capable of reproducing the structure of such polymers with the highest possible accuracy. One of the main driving forces of the self-assembly of supramolecular structures in conjugated polymers is π–π interaction. Taking it into account is a rather difficult task, especially when constructing mesoscale models. In this work, we use the electron density functional theory to develop a methodology for calculating conjugated polymers taking into account π–π interaction. The geometric characteristics of stacks of four tetra thiophene molecules were studied. The performed calculations show that the use of the M06-2X-D3 functional makes it possible to correctly model the interactions of oligothiophene molecules and the structure of the resulting aggregates, while semiempirical calculations by the PM7 method of conjugated polymers are suitable only for rapid preliminary optimization of models. The tested calculation technique is of great importance for the parametrization of mesoscale modeling schemes.
Keywords: organic solar cells, organic polymers, thiophenes, quantum chemical calculations, π–π stacking interaction.
Belenkov M.E., Chernov V.M.
Simulation of polymorphic varieties of hexagonal graphene functionalized by hydroxyl groups — page 541
Abstract: Computer simulation of the crystal and electronic structure of hexagonal graphene layers, on the surface of which hydroxyl groups, chemically adsorbed, was performed by the density functional theory method. As a result of calculations, the possibility of the stable existence of five structural varieties of COH–L6 layers was established. The layer density varies from 1,62 to 1,72 mg/m2. The length of the hydrogen-oxygen bond varies in the range from 1,046 to 1,079 Å, and the carbon-oxygen bond-from 1,455 to 1,465 Å. The orientation of the O–H bonds relative to the surface of the layers can vary depending on the choice of the unit cell of the layer. Layer COH–L6–T4 has the minimum sublimation energy equal to 18,69 eV/(COH), and layer COH–L6–T1 has the maximum sublimation energy 18,93 eV/(COH). The electronic structure of all COH layers is characterized by the presence of a direct band gap at the Fermi energy level, varying in the range from 3,02 to 4,56 eV.
Keywords: graphene, chemical adsorption, hydroxyl groups, ab initio calculations, crystal structure, electronic properties, polymorphism.
Belyakova R.M., Kurbanova E.D., Polukhin V.A.
Analysis of Nb – Ni and V – Ni based membrane characteristics — page 552
Abstract: To obtain ultrapure hydrogen by membrane technology, instead of expensive membranes made of Pd alloys, cheaper ones based on metals ( Nb–Ni) and (V–Ni) are considered. Due to alloying of these Ti alloys, the performance of the membranes increased – diffusion and permeability of hydrogen, wear resistance and thermal stability, exceeding the Pd alloys. For crystalline analogs, the problem was also solved by increasing the Ti concentration with the formation of eutectic phases in ternary alloy compositions (Nb85-xTixNi15 and V85-xTixNi15). Hydrogen accumulated in membrane matrices forms specific polyhedral eutectic TСР hydrides up to phase transitions, and upon cooling from 673 to 303К under conditions of thermal expansion from 473 to 673К, it increases the temperature of β-hydride formation and forms NiTi and NiTi2 compounds, which stabilize and protect nano- and crystalline membranes from brittle destruction.
Keywords: Ti alloying, ternary alloys Nb–Ni–Ti, V–Ni–Ti, hydrogenation, absorption, diffusion, hydrogen permeability, phase formation, Me–H hydrides, embrittlement, duplex matrix microstructure.
Malyshev M.D., Tung S-H., Komarov P.V.
Molecular-dynamic simulation of mixtures of modified fullerenes and 1,8-octandithiol — page 562
Abstract: In this work, we report on the results of comparative atomistic modeling of two systems containing functionalized fullerenes of phenyl- C61 -butyric acid methyl ester (PC61BM ) and phenyl- C71 -butyric acid (PC71BM) in the presence of a high-boiling solvent 8,1 -octanedithiol (ODT ). The calculations were performed by full atomistic molecular dynamics with using LAMMPS software package. A fundamental difference in the packaging of PC61BM and PC71BM molecules was detected. In the case of systems with PC61BM , there is a tendency towards gradual separation of the solvent and fullerenes. At the same time, in samples with PC71BM, there is a tendency to the formation of stable three-dimensional network structures formed by two interpenetrating phases: fullerenes and ODT molecules. In order to check the scalability of the observed structural ordering for the mixture of PC71BM with ODT , an additional simulation was performed in a cell with doubled edge size. In this case, we also observe the formation of bicontinual structures from fullerenes and the solvent.
Keywords: atomistic molecular dynamics, modified fullerenes, high-boiling solvent, networks, bicontinual structures.
Myasnichenko V.S., Eshov P.M., Savina K.G., Veselov A.D., Bogdanov S.S., Sdobnyakov N.Yu.
Regularities of structure formation in bimetallic nanoparticles with different crystallization temperatures — page 568
Abstract: In this work, of the structure formation was investigated using Au–Ag, Ti–Al, Ti–V bimetallic nanoparticles as the patterns. These bimetallic nanoparticles have different atomic size mismatches and different crystallization temperatures. A series of molecular dynamics experiments was carried out. Based on their results, the final configurations with the lowest energy were analyzed and the concentration dependences of the mixing energy were obtained. An analysis of the concentration dependences of the mixing energy makes it possible to predict the compositions and sizes of bimetallic nanoparticles, which can exhibit instability, such as for Ti–V bimetallic nanoparticles. The asymmetry of individual concentration dependences of the mixing energy is evidence of specific structural transformations characteristic for the given composition and size. It has been established that structural segregation is characteristic for Au–Ag, Ti–Al bimetallic nanoparticles and it is actively manifested at low concentrations of a more low-melting component. The competing phases in this case are fcc and hcp phases. In addition, for the average sizes considered in the article, the dependence of the crystallization temperature on the composition of bimetallic nanoparticles was investigated.
Keywords: molecular dynamics method, tight-binding potential, bimetallic nanoparticles, structure formation, crystallization temperature, mixing energy, stability.
Pan’kin N.A.
Change in the structure of titanium nanoclusters under thermal exposure: molecular dynamic simulation — page 580
Abstract: Investigation of the structure of nanoclusters at different temperatures is an urgent task of modern materials science. This fact is due to the prospect of their application in the creation of materials with unique physical, mechanical, chemical and operational properties. Computer simulation was carried out by the method of classical molecular dynamics in the LAMMPS software package. To describe the interatomic interaction in the cluster, a modification of the Finnis-Sinclair many-body potential was used. The structure of titanium nanoclusters of various sizes has been studied. They are obtained at various cooling rates from the liquid state. An increase in the cooling rate leads to the formation of a subblock structure and an increase in the number of atoms with a disordered environment. They are due to the fact that high cooling rates impede the equilibrium process of rearrangement of the atomic structure with the formation of long-range order. No regions with an icosahedral structure were found. It is shown that the crystallization temperature and binding energy decrease with decreasing nanocluster size. An increase in the cooling rate increases the temperature difference between the start and end points of crystallization, respectively. The simulation results indicate a less pronounced dimensional dependence of the crystallization temperature – its estimated value for a macroscopic system (810K) is much lower than the value for bulk titanium (1940 K).
Keywords: nanocluster, binding energy, crystallization temperature, cooling rate, structure, molecular dynamics method.
Ryzhkova D.A., Gafner S.L., Gafner Yu.Ya.
Role of «magic» HCP numbers in stability of the internal structure of Ag89 and Ag153 nanoclusters — page 593
Abstract: Currently, silver is actively used in microelectronics, mainly due to its high electrical and thermal conductivity. Taking into account the processes of interaction between a metal and a light wave (plasmon effects) gives completely new technical applications of silver. These applications are made possible by the strong interaction between incident light and free electrons in nanostructures. By now, it has already become clear that the size, shape, and structure of nanoparticles determine their plasmon properties, including resonance frequencies. Therefore, by adjusting the size, appearance of the metal nanostructure and its internal structure, it is possible to control light with a very high degree of accuracy. In this work, the boundaries of thermal stability of various initial structural phases in small silver clusters with the number of atoms corresponding to the «magic» numbers of the hcp structure were studied by the molecular dynamics method using the modified tight-binding potential TB-SMA (second moment approximation of tight-binding). It was shown that the nature of thermally induced structural transitions in the groups of nanoclusters under study differs sharply. This fact can make it possible to create small silver clusters with the required internal structure.
Keywords: nanoclusters, silver, computer simulation, «magic» numbers, hcp structure, tight-binding.
Ryzhkova D.A., Gafner S.L., Gafner Yu.Ya.
Structural stability of Ag55 and Ag147 nanoclusters with a change in the initial morphology — page 604
Abstract: This article provides a comparative analysis of thermally induced structural transitions in silver nanoclusters with a change in their initial morphology. The study was executed by the molecular dynamics method using the modified TB-SMA (second moment approximation of tight-binding) tight binding potential. The number of atoms in nanoclusters corresponds to the icosahedral structure «magic» numbers. It is shown that for nanoclusters with the initial FCC configuration, the Ih modification is formed either at the stage of preliminary thermal relaxation or during further heating. For nanoclusters with an initial amorphous morphology, the nature of structural transitions undergoes significant changes. For example, the formed Ih modification is more stable at high temperatures and the melting point of nanoclusters shifts by more than 100 K. This effect is due to a smoother change in the specific potential energy of the nanocluster in comparison with the case when a stable Ih configuration is formed at low temperatures. The data obtained can be used in processes to create silver nanoclusters with the required internal structure.
Keywords: structure stability, nanoclusters, silver, computer simulation, structure, tight-binding.
Sdobnyakov N.Yu., Bogdanov S.S., Veselov A.D., Savina K.G., Nepsha N.I., Kolosov A.Yu., Myasnichenko V.S.
Influence of the size effect on the regularities of the structure formation in bimetallic Au-Co nanoparticles — page 612
Abstract: This work studied bimetallic Au–Co nanoparticles of three stoichiometric compositions of various sizes by the molecular dynamics method using the tight-binding potential. The regularities of structure formation are established, their characteristic features are described. In particular, in compositions with 50at% and 75at% Au content, multiple small nuclei of local icosahedral symmetry are formed. Crystalline phases prevail only in the Co -25 at% Au composition with an increase in the particle size. Compositions are revealed in which the internal symmetry of a nanoparticle is determined by the presence of one icosahedron or a superstructure of several icosahedrons. The concentration dependences of the mixing energy of a bimetallic Au–Co nanoparticle are calculated. It is shown that there are concentrations of compositions at which bimetallic nanoalloys can exhibit instability in a certain size range. Crystallization temperatures were determined using the caloric curves of the potential part of the internal energy. It was found that the crystallization temperature demonstrates a moderate or significant, depending on the composition as well as growth with an increase in the size of bimetallic Au–Co nanoparticles.
Keywords: molecular dynamics method, bimetallic nanoparticles, cobalt, gold, size mismatch, structure formation, stability, crystallization temperature, mixing energy.
Sokolov D.N., Sdobnyakov N.Yu., Savina K.G., Kolosov A.Yu., Myasnichenko V.S.
New opportunities for high-performance simulations of nanosystem using Metropolis software — page 624
Abstract: The architecture and software Metropolis for computer simulation by the Monte Carlo method, as well as its modifications, are described. The tight-binding potential that does not exclude the possibility of using other modifications of many-body potentials. In comparison with previous software implementations of the Monte Carlo method, this modification has increased the rate of calculations by 700 times for a selected nanoparticle size. The data on the convergence of the results of modeling by the Monte Carlo method are presented on the example of the melting point. The developed software package is constantly tested for calculations of various mono- and multicomponent nanoparticles and nanosystems. The results obtained show fairly good agreement with other numerical methods, primarily molecular dynamics, and real experiment. Further development of the software package and its performance indicators are planned to be improved using parallelization of computations and the use of computing technology on graphics processors CUDA.
Keywords: computer experiment, Monte Carlo method, hybrid methods, nanoparticles, Metropolis API interface.
Chepkasov I.V.
Study of potassium intercalation in the graphene / MoS2 structure — page 639
Abstract: Using modern ab-initio calculations, in this work, we systematically studied the intercalation of potassium atoms into a hybrid two-layer graphene/MoS2 structure. In the course of the study, concentrations of potassium atoms were determined at which the formation energy is negative. So, in particular, when the concentration of potassium atoms (in relation to molybdenum atoms) is not more than x=0,43, formation of a layer of potassium atoms between the graphene/MoS2 layers is energetically favorable. Beginning with the concentration of potassium atoms x>0,75, an increase in the distance between the graphene and MoS2 layers is observed, which further leads to destruction of the structure. Calculation of charges showed that a potassium atom at low concentrations gives up about 0,8–0,85 electrons, 0,35 of which flow on carbon atoms, and 0,4–0,5 to molybdenum disulfide. Calculation of the difference in electron densities showed that the bond between the layers of graphene, molybdenum and potassium disulfide has a covalent nature.
Keywords: potassium-ion batteries, anodes, intercalation, transition metal dichalcogenides, graphene, density functional theory.
4. PHYSICAL AND CHEMICAL BASES OF NANOTECHNOLOGIES — page 646
Bakhvalova E.S., Bykov A.V., Nikoshvili L.Zh., Kiwi-Minsker L.
Influence of halogen nature on the adsorption ability of aryl halides on palladium clusters — page 646
Abstract: In this paper, the density functional theory calculations were carried out in order to find the adsorption energies of a benzene ring on small Pd0 clusters consisting of four or nine atoms. The adsorption of benzene on palladium clusters was found to result in a noticeable energy gain of the system: –146 kJ/mol in the case of Pd4, and –117 kJ/mol in the case of Pd9 . The adsorption energies of chloro-, bromo- and iodoanisole on Pd4⚹C6H6 were also calculated. The adsorption of iodoanisole was characterized by the highest energy gain of the system (–278 kJ/mol) and occurred dissociatively without activation, that fundamentally distinguished it from chloro- and bromoanisole. The data obtained can be used to explain the differences in the behavior of catalysts based on hyper- cross-linked polystyrene in cross-coupling reactions of various aryl halides and phenylboronic acid, and also the fact that aryl iodides can favor the formation of homogeneous forms of palladium.
Keywords: palladium, clusters, aryl halides, Suzuki cross-coupling, density functional theory.
Bogdanova E.A., Skachkov V.M., Giniyatullin I.M., Pereverzev D.I., Nefedova K.V.
Preparation of biocomposites based on nanoscale hydroxyapatite with zirconium and silicon oxides — page 655
Abstract: The article discusses the possibility of obtaining a hardened composite material with a porous structure based on nanostructured hydroxyapatite (HAP) synthesized by precipitation from a solution. The new material was obtained by the mechanochemical synthesis of HAP with reinforcing additives of zirconium dioxide and silicic acid. The synthesized samples are certified using modern physico- chemical methods of analysis. The influence of the qualitative and quantitative composition of the composite on the sintering processes, porosity, strength characteristics, the degree of dispersion and morphology of the studied samples is shown. It has been experimentally established that the sample has the maximum strength characteristics and a constant composition of Ca10(PO4)6(OH)2–15%SiO2·nH2O–5%ZrO2. The composite material has a dense uniform structure with a high degree of crystallinity, with a developed porosity, is a promising material for further research in order to introduce it into medical practice. A patent application has been filed for the developed composite material.
Keywords: hydroxyapatite, zirconium oxide, silicon oxide, composite biomaterials, crystallinity, microhardness.
Bogdanova E.A., Skachkov V.M.
Promising composite materials based on nanoscale apatite with gelatin as a binding agent — page 664
Abstract: Nanoscale hydroxyapatite and fluorapatite powders were synthesized by precipitation from solutions. Food gelatin is used as a binder. This composition has a high adhesion on materials of different nature and porosity. Porous films and granules with a developed specific surface area were also obtained. Their microstructures are considered. The possibility of using a colloidal suspension and an aqueous suspension of crystalline apatite in combination with a gelatin solution as a bioactive material, both for creating coatings and obtaining granules, has been studied. It is established that the use of apatite powder together with gelatin can significantly reduce the time of formation of a bioactive coating and significantly increase its adhesive strength. The obtained apatite granules are compared in size depending on the concentration of gelatin in an aqueous solution. Patent applications have been filed for the developed bioactive coatings and granular material based on nanoscale apatite with a binding agent.
Keywords: hydroxyapatite, fluorsubstituted hydroxyapatite, gelatin, collagen, biomaterial, bioactive coatings, adhesion, granules.
Zernitsa D.A., Shepelevich V.G.
Study of the structure and properties of lead-free rapidly solidified zinc-based alloys during a heat treatment — page 672
Abstract: The results of studies of the effect of ultrahigh melt cooling rates, equal to at least 105 K/s, on the properties of rapidly solidified alloys of the Zn–Sn system are presented. The upper region of the foil, in contact with the crystallizer during solidification, had more dispersed particles of the second phase, and as the distance from the upper layers increased, the particle sizes increased. At room temperature, the decomposition of a supersaturated solid solution proceeds with the release of dispersed particles. Additional heat treatment leads to the coarsening of the particles of the second phase, and helps to reduce the microhardness. Rapidly solidified foils with a maximum zinc concentration are characterized by the presence of a (0001) texture, which weakens as the tin content in zinc increases, and upon alloying up to 30 wt. % Sn is rearranged to (1010) texture. Heat treatment up to 160 °C does not change the texture.
Keywords: rapidly solidification, lead-free solders, Zn–Sn alloy, microhardness, unit cell, isochronous annealing, decomposition, solid solution.
Ivanov D.V., Anofriev V.A., Koshelev V.A., Antonov A.S., Vasilyev S.A., Sdobnyakov N.Yu.
Simulation of layer by layer growth of fractal metal Pt-Rh films — page 682
Abstract: In this work, the molecular dynamics method and the tight-binding potential are used to simulate the process of molecular beam epitaxy in order to determine the regularities in the formation of fractal platinum metal films on the rhodium surface. The possibility of formation of fractal structures both in island platinum films on the rhodium surface and in a continuous film has been established. The parameters of the computer experiment, which determine the transition from individual island films to a continuous film in the indicated system, have been established. Using various software products Gwyddion and Image Analysis, as well as our own software FractalSurface, the range of changes in the fractal dimension has been analyzed under various conditions of a molecular dynamics experiment by the method of cube counting. The obtained values of the fractal dimension are generally in acceptable agreement with each other; however, there is a number of exceptions, which are discussed in more detail. A comparative analysis of the results obtained allows one to formulate recommendations for the methodology for creating, adjusting and precision control when «growing» structures with a given surface morphology.
Keywords: molecular beam epitaxy, molecular dynamics modeling, tight-binding potential, fractal dimension, cube counting, platinum, rhodium, imaging software.
Ivanov Yu.F., Abzaev Yu.A., Klopotov A.A., Prokopenko N.A., Tolkachev O.S., Nikitin P.Yu., Shugurov V.V., Teresov A.D., Petyukevich M.S.
Features of the structural phase state of a film based on a high-entropy AlNbTiZrСu alloy synthesized by deposition of a multi-element metal plasma — page 693
Abstract: This paper presents the results of structural studies of films with a thickness of up to 5 microns of high-entropy alloys of the AlNbTiZrCu system. The films were synthesized on metal and cermet substrates by deposition of a multielement metal plasma created by electric arc plasma assisted simultaneous independent sputtering of several cathodes. It is shown that the films are a layered material and have an amorphous-crystalline structure. It was found that irradiation of films with a pulsed electron beam (18 keV, 20 J/cm2, 50 μs, 3 imp., 0,3 s-1) is accompanied by crystallization of the material. It is shown that the resulting films are dominated by the compound of the AlNbTiZr composition with the lattice parameter of 0,32344 nm. On the basis of theoretical calculations, the structural data of the crystal AlTi0,86Zr0,95Nb lattice were obtained, mechanical and thermodynamic characteristics of this compound were determined.
Keywords: high-entropy alloy, low-pressure gas discharge plasma, film/substrate system, pulsed electron beam, phase composition, structure.
Klychkov N.A., Simakov V.V., Sinev I.V., Timoshenko D.A.
Dynamics of response of a sensor based on a nanostructured tin dioxide layer exposed to the isopropanol vapors — page 708
Abstract: Nanostructured gas-sensitive tin dioxide films have been synthesized by sol-gel technology. A conductivity vs temperature dependence of a gas sensor into atmosphere of synthetic air has been investigated. A response vs temperature dependence of a gas sensor into atmosphere of isopropanol vapors with various concentrations has been investigated. Local minimum on the temperature dependence of the tin dioxide film conductivity in clean air atmosphere were observed. A decrease in conductivity with increase temperature in the range of 300…350 °C can be associated with a dissociation molecular form of the adsorbed oxygen. At temperatures above 350 °C, conductivity increases because of desorption of the atomic form of the adsorbed oxygen on the surface of gas-sensitive tin dioxide film. The greatest response value is achieved at a sensor temperature equal to 350 °C. It is proposed that the reason is a domination of the atomic form of the chemisorbed oxygen on the surface. The analysis of response time vs concentration and response time vs temperature of gas sensor has been carried out. Sensor response time decreases monotonically with increase admixture substance in gas-probes, apparently because of increase in adsorption rate admixture particles on the surface of gas-sensitive film. It was found that the dependence of the response time on the operating temperature has an Arrhenius form. This may be associated with thermally activated adsorption-desorption processes and heterogeneous chemical reactions on the surface of sensor active layer.
Keywords: sol-gel method, nanostructured films, tin dioxide, gas sensor response time.
Kovtun A.I., Mysyura A.G.
Physico-chemical properties of a nanocomposite hydrogel coating on a textile carrier for the wound treatment — page 717
Abstract: Nanotechnologies using biopolymers are widely used in biomedical applications. In this work, nanocomposite hydrogels based on natural (chitosan, carboxymethylcellulose) and synthetic (polyvinyl alcohol) polymers with silver nanoparticles for application to a textile carrier have been developed. Carboxymethylcellulose dialdehyde and boric acid were used as crosslinking reagents in the creation of hydrogels. Physicochemical properties (sorption capacity in unilateral contact with the model medium, degree of swelling, vapor permeability, capillarity) of hydrogel coatings on a textile carrier, and the kinetics of the drugs release (lidocaine, dioxidine) included in the hydrogels were determined. It is shown that materials with a two-layer coating are characterized by higher sorption properties relative to saline and a longer release of drugs than materials with a single-layer coating. The release of drugs from the two-layer coatings occurs in two stages with a maximum release within two days. The obtained textile materials with a film nanocomposite hydrogel coating can be used as dressings in the treatment of wounds.
Keywords: hydrogel, silver nanoparticles, textile, chitosan, polyvinyl alcohol, carboxymethylcellulose dialdehyde, drug release kinetics, dressing, wound treatment.
Kurbanova E.D., Belyakova R.M., Polukhin V.A.
Specific structure of effective membrane alloys based on niobium, vanadium and zirconium — page 728
Abstract: With unique mechanical and functional properties, amorphous, nanocrystalline and matrix duplex microstructure membrane alloys based on group V elements actively contribute to the development of hydrogen energy. There are still not completely resolved problems for these new alloys – their low thermal stability, insufficient mechanical strength (plasticity, hardness), and intermetallic and hydride embrittlement. For effective use, alloys with a triple composition are being developed – which, in addition to the elements of group V, also include nickel and titanium as alloying metals. Not only amorphous and nanocrystalline alloys are obtained that are applicable in electronics and power engineering, as well as membrane alloys with a duplex matrix structure that combines amorphous, nano- and quasicrystalline dendritic-hardening phases strengthening the amorphous matrix. In specialized membrane ternary alloys, NiTi and NiTi2 compounds are formed, which stabilize and protect nano- and crystalline membranes from brittle destruction. It has been found that the intense formation of hydrides in these alternative membrane alloys is as undesirable as for palladium-based compounds. The alloys under consideration actually make it possible to obtain high-purity gaseous hydrogen using new compositions instead of expensive membranes based on Pd–Au/Ag/Cu alloys.
Keywords: amorphous and nanocrystalline alloys, nickel, titanium, zirconium, niobium, structurization, membrane gas separation, hydrogen purification, solubility, hydrogen permeability, accumulation, thermal stability, fragility, crystallization, modeling, diffusion, nanophases, Me–H hydrides, embrittlement, duplex matrix microstructure.
Malyshkina O.V., Shishkov G.S., Ivanova A.I.
Optimization of technology for producing a composite based on barium ferrite and barium titanate — page 740
Abstract: It is shown in the work that as a result of sintering of composite samples of barium titanate (80 vol. %) – barium ferrite ( 20 vol. %) in a porcelain crucible at a temperature of 1300 °C, a eutectic appears. As a result of comparing the properties of the samples obtained at different sintering temperatures, it was found that the samples sintered at 1250 °C have optimal properties. The structure and dielectric properties of barium titanate ceramic samples and barium titanate (80 vol. %) – barium ferrite ( 20 vol. %) composite sintered at a temperature of 1250 °C are compared. It has been shown that the addition of 20% barium ferrite to the composition of barium titanate increases the dielectric constant, pyroelectric coefficient, and piezoelectric modulus d33 of the composite of 1,5–2 times compared to barium titanate ceramics, while the value of the piezoelectric modulus d31 remains unchanged. The introduction of 20 % barium ferrite into the barium titanate ceramics is sufficient for the resulting composite to have magnetic characteristics corresponding to pure barium ferrite.
Keywords: multiferroic, barium ferrite, barium titanate, magneto-electric composite, piezoelectric ceramic structure.
Masloboeva S.M.
Analysis of methods for synthesis of a boron-doped lithium niobate charge used for growing single crystals — page 750
Abstract: Known methods of a boron doped lithium niobate charge synthesis were analyzed. Such a charge is applied for the growth by Czochralski of single crystals with high optical quality. Homogeneous doping (the charge is obtained from precursor Nb2O5 : B and Li2CO3 ) was compared with solid phase doping (the charge is obtained from the mixture Li2CO3 : Nb2O5 : H3BO3). Homogeneous doping was determined to help produce LiNbO3 : B crystals with a more uniform distribution of a boron dopant, boron distributes more uniform in the melt volume; technological regimes established during crystal growth become easier. For the first time the paper considers liquidphase charge synthesis method; the method excludes the stage of annealing of homogenized mixture of niobium pentoxide and lithium carbonate. Results are crucial for the choice of technology at growing of boron doped lithium niobate crystals for exact areas of technics.
Keywords: lithium niobate, charge synthesis, single crystal, doping, boron, optical quality.
Ponomareva A.A., Sitnikova V.E., Tсoi K.A.
Formation of sol-gel catalytic coatings to improve the ecological parameters of intermetallic porous burners — page 760
Abstract: The environmental parameters of power equipment are important in terms of minimizing the negative impact on the environment. Intermetallic infrared porous flameless burners are a new generation of burners with improved performance. Gas burners are among the most efficient devices for direct conversion of combustion heat into infrared energy. Despite the improved environmental characteristics of infrared porous burners compared to traditional burners, during operation they can emit unwanted and hazardous combustion products of gas mixtures (or other fuels), especially during transient and high-power modes. In this work, catalytic coatings based on cerium-based oxide systems with a small addition of silicon oxides were obtained. The deposition of the catalytic material on porous intermetallic substrates was controlled using the gravimetric method, optical analysis system, and scanning electron microscopy, and its chemical structure was investigated using IR spectroscopy. The uniform distribution of the coating over the substrate surface and the correspondence of the IR peaks with the chemical composition of the synthesized systems were detected.
Keywords: catalytic coatings, metal oxide structures, porous burners, sol-gel technology, infrared spectroscopy.
Pravilnikova T.I., Golovanova O.A.
Precipitation of calcium phosphates from a model blood plasma solution on steel grade 12X18N10T — page 769
Abstract: The paper presents a study of the processes of precipitation of mineral-organic formations in a model solution of blood plasma in the presence of additives of albumin, glycine, glucose, glutamic and lactic acids. The phase composition of the samples was studied by the X-ray diffraction analysis. Photos were taken to measure the surface area of the sample with modified calcium phosphate. The solid phase coating areas were highlighted in the photos and the degree of coating of steel samples was calculated using the ToupView software. The deposition of the crystal phase occurs on all the studied samples. The differences are in the distribution of crystals on the surface of the plate. The additive albumin inhibits the deposition of hydroxyapatite on the studied samples. It is shown, that additions of glucose, glutamic and lactic acids catalyze the process of hydroxylapatite deposition on the surface of a steel sample. As a percentage of the total area of the image, the largest amount of precipitated hydroxylapatite powder is observed in samples with the addition of glucose.
Keywords: mineral-organic formations, blood plasma, calcifications, crystallization, hydroxylapatite, precipitation, steel grade 12X18N10T.
Raksha E.V., Glazunova V.A., Oskolkova O.N., Sukhov P.V., Volkova G.K., Davydova A.A., Berestneva Yu.V., Savoskin M.V.
Carbon nanoparticles based on thermally expanded graphite: effect of the TEG obtaining route on the particles morphology — page 777
Abstract: The paper presents the investigation results of the morphology of carbon nanoparticles formed during liquid-phase exfoliation of thermally expanded graphite in tert-butanol. The thermally expanded graphite used in this work was obtained by thermal expansion of graphite nitrate with acetic and formic acids in the thermal shock mode at 500 °C and 900 °C. Initial cointercalate was shown by powder X-ray diffraction analysis to be the mixture of the IInd and the IVth stage intercalation compounds. It has been established by transmission electron microscopy that dispersions of carbon nanoparticles formed during the exfoliation of thermally expanded graphite in tert-butanol via sonication contain mainly few-layer graphenes, the planar dimensions of which reach 8 μm. The influence of the conditions for thermally expanded graphite obtaining on the morphology of resulting carbon nanoparticles is discussed. Dispersions based on thermally expanded graphite obtained at a lower temperature, in addition to few-layer graphenes, also contain a significant amount of amorphous carbon particles with planar sizes up to 100 nm.
Keywords: few-layer graphenes, liquid-phase exfoliation, graphite nitrate, cointercalation.
Skachkov V.M.
Change in properties of diffusion-hardening solder in dependence on the composition of the liquid metal component — page 788
Abstract: The article discusses the change in the properties of diffusion-hardening solder in dependence on the composition of the liquid metal component based on low-melting gallium alloys: gallium-tin, gallium-indium-tin and gallium-tin-zinc when interacting with the Spherical copper-tin alloy powder (SCTAP5) subjected to low-temperature (125°С) and high-temperature (500°С) heat treatment. The mechanical properties were evaluated by measuring the microhardness, and the thermal properties were studied by differential thermal analysis. Heat treatment at high temperatures promotes the transition of the solder to an equilibrium state, with a significant increase in hardness. The thermal effects of heat treatment of diffusion-hardening solders are calculated and compared. The phases formed as a result of hardening are determined by X-ray phase analysis. It is shown that different phases and nanoscale intermetallic compounds are formed at different processing temperatures. The improvement of the mechanical properties of diffusion-hardening solder in the presence of zinc dissolved in a gallium liquid alloy has been experimentally proved.
Keywords: composite diffusion-hardening solders, exothermic effects, properties, microhardness, differential thermal analysis, X-ray phase analysis.
Timoshenko D.A., Sinev I.V., Simakov V.V., Klychkov N.A.
Recognition of gas-air mixtures by a single gas sensor based on the tin dioxide nanowhiskers — page 796
Abstract: Tin dioxide nanowhiskers were grown by physical vapor deposition and transferred to the contact system by the frozen drop method. The sensors demonstrate gas-sensitivity. Exposing sensors to the atmosphere contained vapors of reducing-gases leads to an increasing of their conductivity. A long-term drift of the sensor conductivity during reducing-gas exposition was shown. A sensitivity response vs concentration for ethanol, acetone, and propanol- 2 vapors at temperature 300 °C was investigated. Desorption energies of the particles and the positions of the donor levels induced by adsorption of reducing gases particles were calculated by analysis of the conductivity vs concentration dependence. The calculated parameters had a significantly smaller time drift in comparison with the conductivity. Using of these parameters makes possible to recognize gas-air mixtures: classify the each of three studied samples to one of classes.
Keywords: whisker nanocrystals, tin dioxide, gas detection, semiconductor gas sensor, gas sensitivity.
Fomin A.I., Pan’kin N.A.
Phase composition, substructure and residual macrostresses in the surface layer of a tape obtained by electric contact welding — page 802
Abstract: The surface layer of DI50-2 cast iron after its processing by electric contact welding has been investigated by methods of X-ray diffraction and electron microscopy. A 50HVA steel strip was used as a filler material. Processing technologies were used with the creation of an intermediate layer of nickel powder PC-12N-01 and without it. Results on phase composition, substructure and residual stresses are obtained. The system under study consists of α–Fe and γ–Fe phases. Substructure parameters (microstrain and block refinement) have the same values for different modes of electrical contact welding. Residual stresses are of a tensile nature and decrease when an intermediate layer of nickel powder material is created. The main mechanism of their formation is thermal effects on the material processed by electrocontact welding. Cracks may form after electrical contact welding of the tape. They are oriented mainly parallel to the surface to be treated and are due to the presence of a large temperature gradient.
Keywords: electrical contact welding, phase composition, microstrains, size of subblocks, macrostresses.
5. NANOCHEMISTRY — page 809
Bibanaeva S.A., Skachkov V.M.
The effect of metal additives on conversion hematite in the processing of bauxite by the Buyer method — page 809
Abstract: The work is devoted to the study of the influence of mono – and composite metal additives on the process of processing bauxite by the hydro-alkaline method. The chemical qualitative and quantitative composition, morphology of red mud (RM) obtained under conditions of autoclave high- temperature leaching were studied. X-ray phase studies aimed at determining the composition and structure of compounds in red mud were carried out. The prospects of the method of autoclave leaching of hard-to-open bauxites with simultaneous extraction of alumina and conversion of hematite to magnetite by hydrogen gas are shown. It was found that the method allows the processing of bauxite with a high degree of alumina extraction and allows to obtain red mud with different magnetic fraction content and low sodium content. The resulting magnetized red mud is suitable for processing by magnetic separation and makes it a promising raw material for the ferrous metallurgy. The dependence of the degree of conversion of hematite to magnetite on the type of reducing agent is determined. According to the results of the research, a patent for the invention was obtained.
Keywords: the bauxite leaching, the recovery of iron, the Bayer process, red mud, hematite, magnetite.
Glazov I.E., Krut’ko V.K., Vlasov R.A., Musskaya O.N., Kul’bitskaya L.V., Kulak A.I.
Precipitation of hybrid hydroxyapatite / autofibrin nanocomposites — page 818
Abstract: Hybrid composites based on hydroxyapatite and autofibrin were synthesized by precipitation in a medium with pH=9. Soft precipitation conditions and rapid isolation of the composite precipitates favored preservation of a biopolymer matrix of autofibrin. An effect of fibrin macromolecules contributed to destabilization of the amorphous calcium phosphate phase and formation of stoichiometric hydroxyapatite. The medium of the citrated plasma stimulated precipitation of calcium-deficient hydroxyapatite with x≈0,1 and the Ca/P ration of 1,65 which transformed into the mixture of hydroxyapatite / β -tricalcium phosphate at 800 °С. Biomimetic apatite composites were synthesized with an addition of 30 vol. % of a Simulated Body Fluid (SBF) model solution. The effect of Mg2+, CO32- ions of SBF promoted the stabilization of amorphous calcium phosphate and formation of carbonated hydroxyapatite that exhibited thermal stability up to 800 °С. The cummulative effect of autofibrin and ions of induced SBF provided controlling composition of the mineral part of hybrid nanocomposites without disruption of an autofibrin matrix.
Keywords: hybrid nanocomposite, hydroxyapatite, fibrin, citrated plasma, amorphous calcium phosphate, calcium-deficient hydroxyapatite, carbonated hydroxyapatite.
Golovanova O.A.
Synthesis and properties of Sr-containing trycalcium phosphate — page 829
Abstract: Sr -substituted tricalcium phosphate was obtained by precipitation from aqueous solutions. Synthetic solid phases were investigated using X-ray phase analysis, IR spectroscopy, scanning electron microscopy, energy dispersive analysis. The supernatant was examined for the presence of Ca2+ and PO43- ions to calculate the Ca/ P ratio. It was revealed that strontium ions are part of tricalcium phosphate, but do not change its phase composition. The addition of strontium ions to the initial solution contributes to a decrease in the size of crystallites and an increase in their porosity. When studying the bioresorbability of the obtained samples using direct potentiometry, it was found that the samples containing strontium ions in their composition have a lower value of the rate of resorption. Energy dispersive analysis data confirmed that strontium ions are included in the composition of TCP samples. But with an increase in their concentration, complete replacement of calcium ions with strontium ions in the TCP structure does not occur. At the same time, the highest values of the dissolution rate are recorded in acidic media.
Keywords: crystallization, calcium phosphates, substituted tricalcium phosphate, strontium, bioresorbability.
Gubarev Yu.A., Lebedeva N.Sh., Tonkushina M.O., Gagarin I.D., Golub A.Yu.., Ostroushko A.A.
Interaction of iron-containing nanocluster polyoxometalate with doxorubicin — page 841
Abstract: Actual problem in the field of targeted drug delivery is transport of highly toxic drugs, with undesirable side effects, in particular antitumor medicine. The thermodynamic parameters of complexation between nanocluster polyoxometalate {Mo72Fe30}, promising as a means of targeted drug delivery, and a cytostatic agent – doxorubicin, widely used in clinical practice, were studied. The interaction of doxorubicin with {Mo72Fe30} was accompanied by an exothermic effect, which indicates an energetically favorable formation of the complex. The kinetics of the release of doxorubicin from the complex in a buffer solution with a pH corresponding to the pH value of blood was studied by fluorescence spectroscopy. The rate constants of destruction processes in the complex, accompanied by the release of doxorubicin, and further complexation of the released doxorubicin with decay products were determined. In the future, it is possible to slow down the release of doxorubicin by stabilizing the {Mo72Fe30}, for example, when it is associated with albumin.
Keywords: Nanocluster polyoxometalates, doxorubicin, complexation, targeted delivery, nanoparticles, rate constant, thermodynamic parameters.
Klychkov N.A., Simakov V.V., Sinev I.V., Timoshenko D.A.
Multiparametric recognition of organic vapors by using a gas sensor based on a nanostructured tin dioxide film — page 852
Abstract: The influence of organic vapors (isopropanol, ethanol, and acetone) with different concentrations in air on a response gas sensor based on nanostructured tin dioxide films synthesized by the sol-gel method was studied. It was found experimentally that inject of the gas mixtures containing organic vapors into measure chamber results to an increase of the conductivity of nanostructured tin dioxide films. In the area of high concentrations (more than 50% of saturated vapor), the concentration dependence of conductivity trends to saturation. The recognizing possibility of species gas admixture by using statistical processing of response only single sensor at different analyzed gas mixture concentrations is validated. The surface donor level of gas-reducing relative to acceptor level oxygen and desorption heat of gas particle were determined. A new method based multiparametric recognition gas mixtures is proposed based on using concentration-independent physical and chemical parameters of analyzed gases as classification properties. It is shown that proposed multiparametric recognition method has higher reliability in comparison with standard methods based on the analysis gas sensor response.
Keywords: gas sensor, sol-gel method, signals preprocessing, adsorption center parameters, multiparametric recognition of gas mixtures.
Krut’ko V.K., Doroshenko A.E., Musskaya O.N., Rabchynski S.M., Kulak A.I.
Apatites formation on electrodeposited calcium phosphates in the Ca(NO3)2 / NH4H2PO4 and CаCO3 / Ca(H2PO4)2 systems — page 860
Abstract: Calcium phosphate coatings on titanium plates were obtained by electrochemical deposition at room temperature in a two-electrode cell at a constant current density of 30 mA/sm2 and a deposition time of 10 min, and brushite coatings from Ca(NO3)2/NH4H2PO4 system at pH = 4, and composite (brushite/calcite/apatite) coatings from the CaCO3/Ca(H2PO4)2 system at pH = 5. The apatite-forming ability (bioactivity) was determined by soaking both types of calcium phosphate coatings in a model SBF solution during month. The newly formed amorphized apatite layer after heat treatment at 800 °С crystallized into β –tricalcium phosphate/hydroxyapatite on brushite coatings and hydroxyapatite on composite coatings due to the presence of calcite, whose carbonate ions initiate formation of hydroxyapatite, as well as apatite nanoparticles in the initial coating. The obtained calcium phosphate coatings are promising as biocoatings capable to increase osseointegration of metal implants.
Keywords: calcium phosphate coatings, brushite, calcite, SBF model solution, apatite, hydroxyapatite.
Krut’ko V.K., Maslova L.Yu., Musskaya O.N., Safronova T.V., Kulak A.I.
Modification of calcium phosphate foam ceramics with bioapatite in SBF solution — page 870
Abstract: The multiphase calcium phosphate foam ceramics, represented by β -tricalcium phosphate ( 65%) and β -calcium pyrophosphate ( 25 %),including hydroxyapatite (5 %) and α -tricalcium phosphate (5 %), with 60–64 % porosity and a through architecture of polyurethane foam was obtained. The application of a layer of hydroxyapatite led to an increase in the content of hydroxyapatite to 25 %, α -tricalcium phosphate to 40%, and an increase in static strength to 0,03 MPa with a decrease in porosity to 49%. The application of the second layer of hydroxyapatite promoted an increase in the content of hydroxyapatite to 40%, the static strength reached 0,05 MPa at a porosity 40 %. The bioapatite formation in the shape of «foam spheres» with a size from 2 to 10 μm occurred in the process of modifying all types of foam ceramics in a SBF solution during 21 – 28 days. The modified calcium phosphate foam ceramics enriched with α -tricalcium phosphate and hydroxyapatite, was characterized by the maximum static strength 0,08 MPa at a porosity 38%.
Keywords: calcium phosphate foam ceramics, hydroxyapatite, polyurethane foam, tricalcium phosphate, SBF (Simulated body fluid), bioapatite.
Kryukov T.V., Feofanova M.A., Skobin M.I., Ivanova A.I.
Synthesis and physicochemical study of the cerium and cefazolin metal complex — page 881
Abstract: In this work, a team of authors obtained and isolated in solid form a metal complex compound by the interaction of aqueous solutions of trivalent cerium chloride and sodium salt of cefazolin. Its elemental composition was determined using the X-ray spectral electron probe analysis. The thermal characteristics of this compound, the temperature of its decomposition, the composition and the method of coordination of the inner sphere of this metal complex were clarified by the methods of thermogravimetry, differential scanning calorimetry and IR spectroscopy. Based on the data obtained, the inner sphere of the metal complex contains three molecules of cefazolin and three molecules of inner-sphere water. The composition of the inner sphere corresponds to the formula [CeCzl3(H2O)3]. Taking into account IR spectroscopy data, the authors concluded that the most likely way of coordination of cefazolin to the central ion is through the amide and carboxyl groups.
Keywords: coordination compounds of rare earth elements, cefazolin, cefazolin complexes, cephalosporins.
Malkanduev Yu.A., Kokoevа A.A., Dzhalilov A.T.
Polymerization by interaction α-haloacrylic acids with tertiary amines — page 890
Abstract: The results of spontaneous polymerization of α -chloroacrylic and α -bromoacrylic acids with tertiary amines at a low temperature are presented. As a result of spontaneous polymerization during the interaction of α -halodacrylic acids with tertiary amines, polymers containing quaternary ammonium groups are formed. In order to confirm this assumption, nuclear magnetic resonance and infrared spectroscopic studies of the products of the spontaneous polymerization were carried out. Spontaneous polymerization proceeds, consisting of two stages: the quaternization reaction and the polymerization reaction. The kinetic regularities of the polymerization reaction were studied and it was shown that the quaternization reaction, which is the limiting stage of the spontaneous polymerization process, proceeds according to the SN2–mechanism. It has described the first attempts to obtain new nanocomposite materials based on synthesized copolymers and modified montmorillonite. Analysis of the literature data shows that the features of the preparation of nanocomposites based on Na+–montmorillonite and water-soluble copolymers have not been previously studied.
Keywords: polyelectrolytes, chloroacrylic acid, bromoacrylic acid, spontaneous polymerization, polymerization kinetics, quaternary ammonium salts, composite.
Medyankina I.S., Skachkov V.M., Pasechnik L.A.
Kinetics aspect of hydrochemical fluorination of silicon-containing industrial waste — page 900
Abstract: A method for producing amorphous silica from the enrichment wastes of low-titanium vanadium containing titanomagnetites of JSC «EVRAZ ZSMK» – wet magnetic separation tailings is proposed. The use of a NH4HF2 solution makes it possible to practically selectively extract silicon into the solution in the form of ammonium hexafluorosilicate. The extraction of silicon with 1,0–2,5 wt.% NH4HF2 solution for 6 hours reached 46 %. The diffusion process of the silicon extraction is described by the kinetic equation 1–(1–α)1/3=0,0043·exp(–5230 / RT)·τ. Amorphous silica obtained by the sol-gel method from a fluoride silicon-containing solution has a highly developed surface 320 m2/g, the particle size calculated from the average density of «white carbon black» is of 10 nm. The increase in concentration to 20 wt. % NH4HF2 leads to the rise of the silicon solubility and of other tailings components, which are unwanted impurities in the final product. In general, it is shown that the hydrochemical leaching of silicon-containing industrial waste – tailings with weak solutions of ammonium hydrofluoride is promising for the synthesis of pure amorphous silica.
Keywords: wet magnetic separation tailings, amorphous silica, ammonium hydrofluoride, fluorination, kinetics of the process.
Nalimova S.S., Shomakhov Z.V., Punegova K.N., Ryabko A.A., Maximov A.I.
Synthesis and study of gas-sensitive nanostructures of the Zn–Sn–O system — page 910
Abstract: Zinc oxide nanorods were synthesized by the hydrothermal method. The obtained samples were processed in an aqueous-alcohol solution of potassium stannate and urea at 170 °C during different times. As a result, Zn–Sn–O nanostructures were obtained. The surface chemical composition of ZnO and Zn–Sn–O was studied using the X-ray photoelectron spectroscopy. Its sensitivity to vapors of isopropyl alcohol (1000 ppm) at 120 °C, 180 °C, 250°C was analyzed. The electron density redistribution during the Zn–Sn–O composite nanostructures formation manifests itself in the chemical shift of the O1s and Zn2p peaks. It confirm the rearrangement of chemical bonds when zinc atoms are replaced by tin ones. It was found that the sensitivity of composite structures to isopropyl alcohol vapors significantly exceeds that of ZnO in the entire temperature range under study. The improvement of gas-sensitive properties is associated with the presence of various types of surface centers in the Zn–Sn–O samples that participate in the adsorption and oxidation of isopropyl alcohol.
Keywords: zinc oxide, zinc stannate, gas sensors, nanorods, X-ray photoelectron spectroscopy.
Rozhentsev D.A., Mansurov R.R., Tkachev N.K., Russkikh O.V., Ostroushko A.A.
Catalytic properties in the heterogeneous Fenton reaction of the surface of nanoporous iron obtained by electrochemical dealoiyng in melted chloride mixtures — page 919
Abstract: The samples of partially oxidized micro- and nanoporous iron obtained by high-temperature dealloing of an iron-manganese alloy in a molten salt were investigated. The data concerning the structure of the samples and the composition of their surface were obtained by electron microscopy; it was found that after washing at room temperature in air the oxide phases of iron were formed as whiskers with a thickness of about 10 nm. During the preparation of the samples a quantitative removal of manganese from the initial alloy was achieved. The catalytic activity of the obtained samples in the heterogeneous Fenton reaction was estimated by oxidation of methyl orange by hydrogen peroxide. The rate of the first stage of the reaction, which was described by the first-order equation, was determined by the most active spent part of the samples, and then the reaction passed into the stationary mode. The nanoporous samples possessed a higher catalytic activity.
Keywords: nanoporous iron, dealloying, iron oxide whiskers, catalytic activity, Fenton reaction.
Kharaev A.M., Bazheva R.Ch.
Study of relaxation transitions in some aromatic polyesters — page 928
Abstract: The spin probe method was used to systematically study the main relaxation transitions of rigid-chain glassy polymers in a wide temperature range using spin probes of different sizes using polysulfone as an example. In the main relaxation region of aromatic polyesters, two inflections were found using the spin probe method. The two inflections found in the temperature dependence of the rotation correlation time are the result of unfreezing of segmental mobility in regions with different packing of segments. It was shown that the high-temperature inflection corresponds to the defrosting of the cooperative-type segmental mobility (α -transition), and the inflection at a lower temperature corresponds to the β -defrosting of the segmental mobility of the local type (the α′-process). To explain the nature of this transition, a theoretical model of the polymer was used, where it is assumed that different levels of supramolecular organization are possible in amorphous polymers, i.e. the existence of more ordered and more densely packed regions, which alternate with looser and less ordered regions. The influence of various factors on the position of the α′-transition on the temperature scale is investigated. The choice of the probe volume on the basis of a strictly substantiated model of its motion made it possible to reveal the relationship between the rotational motion of the probe and the motion of individual segments of the amorphous polymer below the glass transition temperature.
Keywords: polyester, polysulfone, polycarbonate, spin probe method, glass transition temperature, pre-carbonate temperature.
Yasnaya M.A., Blinov A.V., Golik A.B., Maglakelidze D.G., Gvozdenko A.A., Kravtsov A.A., Blinova A.A.
Influence of the polyethylene glycol molecular mass on thermal transitions of nanosized copper oxide — page 937
Abstract: In this work, samples of nanosized copper oxide stabilized with polyethylene glycol of various grades with molecular weights from 200 to 6000 Da were obtained. The crystal structure of the samples was investigated by X-ray diffractometry. As a result of the XRD analysis, it was found that the samples have a monoclinic crystal lattice with space group C2/c . The effect of the molecular weight of the polymer on the size of nanoparticles was studied by the photon correlation spectroscopy method. Analysis of the results showed the presence of one fraction of particles in all samples, the size distribution was monomodal. It was found that the molecular weight of polyethylene glycol has an effect on the CuO particle size in colloidal solutions, while the phase composition and crystallite size remain unchanged. The average hydrodynamic radius of CuO particles in the obtained samples was about 140±40 nm. The smallest hydrodynamic radius of 70±15 nm was observed in a sample of nanosized copper oxide stabilized with polyethylene glycol with a molecular weight of 6000 Da. The effect of stabilizers with different molecular weights on the phase transitions of samples during heat treatment was investigated by the synchronous thermal analysis. As a result of thermal analysis, it was found that the optimum temperature for calcining nanosized CuO powders was 500°C.
Keywords: copper oxide (II), polyethylene glycol, synchronous thermal analysis, XRD, photon correlation spectroscopy.
Foreword — page 7
1. EXPERIMENTAL STUDIES OF NANOPARTICLES, NANOSYSTEMS, AND NANOMATERIALS — page 8
Bazzal K., Alekseenko N.A., Voropay E.S., Kovalenko M.N., Trinh N.H., Zajogin A.P.
Spectral studies of the processes of aluminum nanopowder formation exposed by short series of twin laser pulses in the air atmosphere — page 8
Abstract: The processes of formation of oxidized nanopowders depending on the number of pulses were studied when double laser pulses with an energy of 52 mJ and an interpulse interval of 10 microseconds were applied to an aluminum target placed in a closed rectangular glass cuvette. It was found that the highest intensity of the Al III ion lines is observed at a small, about 15 pulses, consecutive double pulses in a series. The size of primary particles estimated by high-resolution electron microscopy was mainly 50-60 nm, and the particles were collected in agglomerates.
Keywords: oxidized nanopowders Al, Al2O3, AlO suboxides, pulsed laser sputtering, laser plasma, laser spark spectrometry, multicharged ions, dual laser pulses.
Barabanova E.V., Ospelnikov N.M., Ivanova A.I.
Electrophysical properties of solid solutions NaNb1-xFexO3-δ (x=0; 0,1; 0,2) — page 16
Abstract: Introduction of dopants is a classic method for modifying properties of perovskite complex oxides of the family of general formula ABO3. Sodium niobate NaNbO3 is widely used as a basis for creating solid solutions. The introduction of substitutional cations is carried out at both position A and at position B. Of particular interest is the case when valence of the dopant is greater or less than valence of the initial cation at the site. In this case, a defected structure is formed, which may have unique properties. This work is devoted to study of the electrical properties of sodium niobate ceramics doped with Fe3+. The substitution was carried out according to positions of the nibium cations Na5+. It is shown that such compositions are characterized by a significant increase in electrical conductivity, a decrease in the Curie temperature, and a diffuse of the phase transition.
Keywords: ionic conductivity, cation vacancy, ferroelectric solid solutions, sodium niobate, dielectric permittivity, diffuse phase transition, ferroelectric relaxors.
Blinov A.V., Kravtsov A.A., Raffa V.V., Kramarenko V.N., Krandievsky S.O., Maglakelidze D.G., Blinova A.A.
Influence of synthesis conditions on aggregative stability of Ag alcosols — page 25
Abstract: For the first time, the paper presents the results of investigation the effect of the type of alcoholic medium on the properties of highly concentrated sols of silver nanoparticles. Spectrophotometry revealed the presence of a selective absorption band corresponding to the surface plasmon resonance of silver nanoparticles. Measurement of the zetta potential showed that, regardless of the type of medium, the surface of silver nanoparticles is negatively charged. It was found that the most aggregatively stable particles that retain stability even in concentrated sodium chloride solutions were obtained in isopropyl alcohol and are characterized by the zetta potential equal to -99.8 mV.
Keywords: silver nanoparticles, optical properties, electroacoustic spectroscopy, zeta potential, nanoparticle stability.
Blinov A.V., Maglakelidze D.G., Kravtsov A.A., Blinova A.A., Gvozdenko A.A., Golik A.B., Raffa V.V., Konovalova E.V.
Influence of active acidity of the medium on the stability of MnO2 nanoparticles — page 33
Abstract: In this work, for the first time the results of studying the microstructure of manganese dioxide nanoparticles stabilized with sulfur-containing amino acids are presented. According to the results of scanning electron microscopy, nanoparticles with a diameter of 15-30 nm were presented in the samples. The optimal mass ratios of precursors were established by means of spectrophotometry, to obtain stable sols of manganese dioxide nanoparticles. The optimal mass ratios were: KMnO4: methionine – 1:1 and KMnO4: cysteine – 3:1. Investigation of the effect of the medium active acidity on the stability of manganese dioxide nanoparticles showed that MnO2 samples obtained with methionine are stable at 4 ≤ pH ≤ 11, and with cysteine – at 5 ≤ pH ≤ 8.
Keywords: active acidity of the medium, manganese dioxide, nanoparticles, spectrophotometry.
Bolshakova N.N., Zaviyalova S.D., Nekrasova G.M., Semenova E.M.
Effects of niobium-doping on the dielectric and switching properties of barium titanate crystals — page 42
Abstract: This paper reports the results of investigations of dielectric properties, switching processes and the domain structure of niobium-containing barium titanate crystals. It was shown that an impurity of niobium Nb5+, whose ions replace Ti4+ and change the ionic composition of the lattice, is important for behavior of the domain structure of BaTiO3:Nb5+ crystals. At a change in temperature (0,3 K/c-1) a transformation of the domain structure occurs in the BaTiO3:Nb5+ crystals under the influence of the internal thermoelastic stresses ~0,7 MPa and the depolarizing fields ~20 kV/m.
Keywords: BaTiO3, unipolar crystals, polarization switching, ligand.
Dementev P.A., Lapushkin M.N.
Changes in the structure of gold nanoparticles on the tungsten surface caused by heating — page 53
Abstract: The formation of gold nanoparticles on the tungsten surface and the effect of heating on their structure are studied. It was found that the thermal deposition of gold atoms on the tungsten surface at room temperature leads to formation of randomly located nanoparticles. The average area of nanoparticles is 10210 nm2. Heating for 30 minutes at a temperature of 600K leads to the fusion of nanoparticles, which is reflected in an increase in the average area of nanoparticles to 19520 nm2. Further heating for 30 minutes at temperature 600K did not lead to an increase in the average area of nanoparticles. An analysis of the shape of the nanoparticles showed that they are elongated ellipsoids. Unheated nanoparticles have a semi-major axis of 110 ± 30 nm and eccentricity 1,5 ± 0,4. Heating of gold nanoparticles leads to an increase in the semi-major axis to 200 ± 120 nm and an eccentricity to 1,8 ± 0,6. It is shown that the nanoparticles after heating become a cropped ellipsoid.
Keywords: nanoparticles, atomic force microscopy, surface topography, gold, tungsten.
Efremov V.V., Shcherbina O.B., Palatnikov M.N.
Electric conductivity at room temperature in Li0,12Na0,88Ta0,25Nb0,75O3 synthesized at a high pressure — page 61
Abstract: A ferroelectric solid solution Li0,12Na0,88Ta0,25Nb0,75O3 with a perovskite structure, synthesized under the high pressure and temperature conditions, has been studied by impedance spectroscopy in the temperature range 290-460 K. The values of static conductivity, the most probable relaxation times as functions of temperature, the activation enthalpy of charge carriers, and the real part of the dielectric constant have been determined. It was found that at room temperature Li0,12Na0,88Ta0,25Nb0,75O3 has a high electrical conductivity, close to the superionic one. Possible mechanisms of the discovered phenomenon are discussed.
Keywords: solid solutions, thermobaric synthesis, impedance spectroscopy, electric conductivity, charge carriers activation enthalpy.
Ivanov D.V., Antonov A.S., Semenova E.M., Ivanova A.I., Tretyakov S.A., Sdobnyakov N.Yu.
Obtaining nanosized platinum films with fractal properties — page 73
Abstract: A comprehensive study of the morphology of the relief of nanosized platinum films on the mica surface was carried out using a scanning probe (in the atomic force mode) and tunneling microscopes, as well as an optical interference profilometer. Сharacteristic features of the surface nanorelief of platinum films of various thicknesses, including fractal properties, are described. The values of the fractal dimension were obtained for films of different thicknesses using two alternative methods of investigation at different initial scales of samples: based on the data of an atomic force microscope – Dc = 2,28 ÷ 2,35 and a scanning tunneling microscope – Dc = 2,12 ÷ 2,26. For comparison, experimental data of other authors are presented. Recommendations for development of the technology for «growing» structures with a given surface morphology are proposed.
Keywords: scanning probe microscopy, atomic force microscope mode, scanning tunneling microscopy, nanorelief, roughness parameters, fractal dimension, platinum films.
Ivanov Yu.F., Klopotov A.A., Petrikova E.A., Regina M.E., Tolkachev O.S., Klopotov V.D.
Structural-phase state of silumin of hypereutectic composition irradiated by a pulsed electron beam — page 89
Abstract: Silumin (an alloy of aluminum with silicon) is a cheap industrial alloy with good corrosion resistance, high specific mechanical properties and good casting properties. As a result it has found wide applications in modern industry (aircraft and mechanical engineering, instrument making, shipbuilding, etc.). The aim of this work is to analyze the regularities of transformation of the structure and phase composition of the surface layer of a hypereutectic silumin (Al – 22 wt % Si), subjected to irradiation with an intense pulsed electron beam. It was found that irradiation of silumin with a pulsed electron beam (18 keV, 25 J / cm2, 200 μs, 3 pulses, 0,3 s-1) leads to melting of the surface layer up to 60 μm thick, the high-speed crystallization of which is accompanied by the formation of a submicro-nanocrystalline multiphase structure. It is shown that aluminum (a solid solution based on fcc crystal lattice) forms cells of high-speed crystallization; nanoscale particles of the second phases are located at the cell boundaries. Analysis of three-component state diagrams of the Al-Si-Fe-Cu system (the main elements of the studied silumin) demonstrated the possibility of forming a large number of two- and three-element compounds in the alloy under equilibrium conditions. It has been shown by diffraction electron microscopy that, along with three-element phases, phases based on four and, possibly, more elements are formed in silumin.
Keywords: hypereutectic silumin, pulsed electron beam, elemental and phase composition, defective substructure, equilibrium diagrams.
Ivanova A.I., Semenova E.M., Dunaeva G.G., Ovcharenko S.V., Tretyakov S.A., Zigert A.D.
Influence of defects on magnetic characteristics of ferrite-garnet films — page 103
Abstract: This paper presents a study of the effect of volumetric (bulk) defects associated with the local mechanical damage and thermal laser action on the domain structure and magnetic characteristics of epitaxial bismuth-containing garnet-ferrite Bi : FG magnetic films. It was found that uniaxial Bi : FG films are resistant to bulk defects, the size of which does not exceed the width of the film domains. It is shown that the considered bulk film defects affect the process of the film magnetization, the form of the magnetization curves, the magnitude of the coercive force and the ratio of the displacement field to the coercive force. Effect of femtosecond laser pulses exposure with a power density of 800 J/cm2 on the coercivity of film was found. The 4-fold increase of the coercive field near a defect is discovered (from 0,33 Oe to 1,44 Oe).
Keywords: magnetic films, ferrite garnets, bulk defects, domain structure, coercivity.
Karamurzov B.S., Kutuev R.A., Ponegev M.Kh., Sozaev V.A., Shermetov A.Kh., Shokarov A.A.
Wetting angle polytermes for lead-sodium melts on refractory metals — page 113
Abstract: The temperature dependence of the contact angle for Pb – Na melts of different concentrations on Co – Cr, Ni – Cr and stainless steel 25X18H9C2 substrate was studied by the method of a lying drop. Measurements were carried out by a lying drop method in the temperature range from 359 to 800°C in an atmosphere of pure helium grade A. It is shown that the value of the wetting angle decreases with increasing temperature, wetting thresholds are observed.
Keywords: wetting angle polytherms, wetting threshold, Co – Cr, Ni – Cr, 25X18H9C2 substrates.
Kasumov Yu.N., Manukyants A.R., Sozaev V.A., Khubolov B.M.
Phase formation in contact layers during contact melting of copper and aluminum — page 120
Abstract: In this work, an attempt is made to identify the features of the structure of contact layers during the contact melting of copper with aluminum brand AMG-2 (mass composition, %: Mg – 1,8 – 2,8, Mn – 0,2 –0,6, Cu – 0,1, Zn – 0,2, Fe – 0,4, Si – 0,4, rest – aluminum) and aluminum-lithium alloy (Al – 0,4 wt.% Li). The study of contact melting in the system is important for development of contact-reactive soldering technology, obtaining layered intermetallic composite materials, creating heat sinks for semiconductor devices, modeling dendrite formation. It was established that intermetallic compounds are formed in the contact layers, which affect the brittleness of copper-aluminum compounds and eutectic structures.
Keywords: contact melting, contact interaction, aluminium/copper system, euthetics, phase formation in contact layers.
Kramynin S.P.
The size dependencies of properties of Mo-W alloy of equiatomic composition — page 128
Abstract: Based on the parameters of the Mie–Lennard-Jones pair-wised potential of the interatomic interaction for Mo and W, the potential parameters for an equiatomic Mo – W substitution alloy were calculated. Size dependences for the equation of state, modulus of elasticity, coefficient of thermal expansion, isobaric heat capacity, surface energy and surface energy temperature derivative were obtained. Temperature dependencies of coefficient of thermal expansion and isobaric heat capacity for macro- and nano-crystals of Mo – W alloy were also obtained.
Keywords: tungsten, molybdenum, nanocrystal, alloy, size dependences, equation of state, surface energy.
Malashenko V.V., Malashenko T.I.
The effect of nanoscale defects on the dynamic yield stress of alloys — page 136
Abstract: The high strain rate deformation of aged alloys containing Guinier-Preston zones is theoretically analyzed. The analytical expression for the contribution of the Guinier–Preston zones to the value of the dynamic yield stress has been obtained. It is shown that the dynamic drag of dislocations by nanoscale defects differs significantly from the drag by point defects.
Keywords: dislocations, Guinier-Preston zones, point defects, nanomaterials, high strain rate deformation, dynamic yield stress.
Palatnikov M.N., Sidorov N.V., Kadetova A.V., Teplyakova N.A., Makarova O.V.
Concentration threshold in LiNbO3:Tb crystals — page 142
Abstract: A series of lithium niobate crystals doped with terbium was grown. Processes of crystallization and concentration dependences of structural characteristics were studied in LiNbO3:Tb ([Tb] = 0,1 – 2,89 wt. %) crystals. Comparative studies of the photorefractive properties of crystals LiNbO3:Tb of various chemical composition are carried out. A concentration threshold was determined in crystals near [Tb] ~ 2,2 – 2,3 wt. %. Anomalies of physic-chemical, optical and structural characteristics are observed in this area.
Keywords: single crystal, lithium niobate, doping, terbium, structural characteristics, photorefractive properties, concentration threshold.
Semenova E.M., Lyakhova M.B., Ivanov D.V., Kuznetsova Y.V., Karpenkov D.Yu., Ivanova A.I., Karpenkov A.Yu., Sinkevich A.I., Antonov A.S., Sdobnyakov N.Yu.
Effects of low-temperature treatment on magnetic properties of Sm(Co, Cu, Fe)5 compounds — page 149
Abstract: The results on the micro- and nanostructures and on the magnetic domain structure of Sm(Co0,45, Cu0,40, Fe0,15)5 compound are presented. It was shown that the sequential high- and low-temperature heat treatments lead to formation of a homogeneous microstructure with some nanoscale compositional heterogeneities. Such a structure provides the coercive field HcI of up to 32 kOe. The coercivity and remanent magnetization of the samples in the temperature range from 300 to 700 K linearly decrease. It is shown that the nanostructure of the alloy with the highest HcI corresponds to the fractal dimension Df-n ~ 2,3.
Keywords: Sm(Co, Cu, Fe)5 , coercivity, nanostructure, domain structure, fractal dimension.
Sigaev A.P., Averin I.A., Karmanov A.A., Pronin I.A., Yakushova N.D.
Study of adsorption properties of nanostructured films based on tin dioxide — page 162
Abstract: The results of theoretical and experimental studies of surface properties of nanostructured films based on tin dioxide using Fourier-transform infrared spectroscopy, ellipsometry and the indicator method of the distribution of adsorption centers are presented. Etching in inductively coupled plasma was used for additional post-processing of nanostructured films in order to activate the adsorption centers.
Keywords: sol-gel technology, films, mixed oxides, IR-Fourier spectroscopy, the adsorption centers, spectrophotometry, indicator method of a distribution of adsorption centers, plasma treatment.
Spivak Yu.M., Castro R.A., Sevryugina M.P., Kuznetsova M.A., Moshnikov V.A.
Dielectric relaxation in POR – Si layers at low frequencies — page 170
Abstract: Macroporous silicon with a mesoporous nanostructured surface layer on its top was obtained by a method of electrochemical anodic etching. The frequency dependences of the dielectric coefficients for porous Si layers were measured in the frequency range 5∙10-3 < f < 106 Hz at a temperature of 295 K and an applied voltage of 1 V. A maximum of the dielectric loss tangent is revealed, which is most likely due to the predominance of the dipole relaxation mechanism of polarization. The distribution of relaxers over relaxation times has been. An interpretation of the results obtained from the point of view of the structure of the porous layer is proposed.
Keywords: porous silicon, nanostructured layer, impedance, interface, dielectric relaxation, low-frequency dielectric spectroscopy, ion-electron microscopy.
Starodub O.R., Voskresenskii V.M., Sidorov N.V., Palatnikov M.N.
Influence of a doping ion on the processes of defect formation in simulated lithium niobate clusters — page 180
Abstract: An approach developed by us to calculation of clusters in the structure of a lithium niobate crystal based not on unit cells, but on oxygen clusters, makes it possible to prevent disruption of structures at the boundaries of the cluster and to preserve the electroneutrality of the model cluster. An optimal cluster size with a minimum energy and a structure tending to the structure of a congruent lithium niobate crystal, confirming the energy optimality of a congruent crystal, are found. With the introduction of the dopant ion 3+, in all three cases of concentrations, an energy optimum is observed precisely near the congruent ratio Li / Nb. A decrease in energy is also observed after optimization of the model cluster, which is consistent with the data of spectral analysis on the formation of microclusters with local ordering of the structure inside the crystal.
Keywords: lithium niobate, modeling, clusters, vacancy models, sublattice defects, single crystals, ferroelectrics.
Tvardovskiy A.V., Zaytsev D.S., Fomkin A.A.
Change of thermodynamic characteristics of the carbon adsorbent FAS-3 at adsorption of benzene — page 190
Abstract: For the first time, complex studies were carried out on adsorption deformation – sorbostriction of the microporous carbon adsorbent FAS-3 at adsorption of benzene vapors from the flow of carrier gas – nitrogen in non-equilibrium conditions. Adsorption isotherms of benzene vapors by the microporous carbon adsorbent FAS-3 under equilibrium conditions has been studied. Calculations of changes in the entropy and internal energy of the adsorbent in the adsorption process were performed.
Keywords: adsorption, adsorbent, adsorption deformation of the adsorbent, the dilatometric method of measuring the adsorption deformation of adsorbents, thermodynamics of adsorption deformation of the adsorbent.
Teplyakova N.A., Sidorov N.V., Palatnikov M.N.
Calculation of the point defect concentration of the cation sublattice and hydroxyl groups in lithium niobate crystals of different composition — page 200
Abstract: The IR absorption spectra in the region of stretching vibrations of OH-groups of lithium niobate crystals of stoichiometric and congruent compositions are studied. The results of calculations of the OH-groups concentration, the Li / Nb ratio and the concentration of point defects NbLi and VLi coincide with the literature data. The phase diagram of lithium niobate confirms these results. It is shown that an increase in the number of free protons that contribute to conductivity can lead to reducing the optical damage and higher electrical conductivity and the rate of thermal fixation of holograms.
Keywords: single crystal, lithium niobate, defects, IR absorption spectra, stretching vibrations of OH-group.
Titov R.A., Voskresenskiy V.M., Sidorov N.V., Teplyakova N.A., Palatnikov M.N.
Simulation of structure of LiNbO3 crystals grown with using of B2O3 flux — page 206
Abstract: It is shown that the B3+ element is able to incorporate into the facets of oxygen tetrahedra of LiNbO3 crystal structure ( [BO3]3- group) in a trace amounts (≈10-4 wt. %). In this case, boron noticeably distorts the anion sublattice of the crystal, changing the lengths of the <O – O> bonds, increasing the ordering of structural units of the cation sublattice. At the same time, boron changes the polarizability of the oxygen-octahedral MeO6 clusters (Me – Li, Nb) which determines the ferroelectric and nonlinear optical properties of the crystal.
Keywords: single crystal, lithium niobate, boron oxide, infrared absorption, Raman spectroscopy, computer simulation.
Khubolov B.M.
Electric crystallization of thin films of sodium – tungsten bronze — page 213
Abstract: The paper considers the problems of obtaining thin films of sodium-tungsten bronzes of a cubic structure by the method of electrocrystallization. The main parameters of the obtained films are presented. The reflection spectra of the films were recorded for uncolored and colored films. Investigation of the near-surface layer of sodium-tungsten bronze single crystals by protonography and nuclear reactions showed their high structural perfection. The anodic and cathodic polarizations of single crystals lead to a change in the structure of their surface layer. Depletion in sodium of the near-surface layer is present at both cathodic and anodic polarization, and the depletion depth increases with increasing polarization time of the voltage value. Thin films of sodium-tungsten bronzes have been investigated by electron diffraction, and the amorphous structure of freshly deposited films has been established for all substrate temperatures. Annealing with an electron beam leads to crystallization of the films.
Keywords: sodium-tungsten bronze, electrocrystallization, thin film, single crystal, reflection spectra, electrochromic effect, electrochromic indicator.
Shomakhov Z.V., Nalimova S.S., Kalazhokovv Z.Kh., Moshnikov V.A.
Analysis of changes in the surface composition during formation of zinc stannate nanostructures — page 222
Abstract: Zinc stannate nanostructures were synthesized by hydrothermal method, and zinc oxide nanorods were used as starting materials. Formation of multicomponent oxides was studied by using the X-ray photoelectron spectroscopy. It was found that tin ions are gradually embedded in the crystal lattice of zinc oxide nanorods and replaced zinc ions during hydrothermal synthesis with the formation of zinc stannate nanostructures. The study of the synthesis time effect on the surface chemical composition of the prepared samples has shown formation of zinc stannate after 1 hour, that is confirmed by changes in the binding energies of zinc and oxygen. With a longer synthesis, zinc stannate nanostructures collapsed, thus zinc and tin oxides are practically not observed on the sample surface.
Keywords: zinc stannate, nanostructures, hydrothermal synthesis, x-ray photoelectron spectroscopy.
Yasnaya M.A., Blinov A.V., Blinova A.A., Shevchenko I.M., Maglakelidze D.G., Senkova A.O.
Determination of optimal modes for measuring the size of colloidal particles by photon-correlation spectroscopy and acoustic spectroscopy — page 232
Abstract: This paper presents the results of measuring the size of colloidal SiO2 particles by two methods – photon-correlation spectroscopy of dynamic light scattering and acoustic spectroscopy. Mathematical processing of experimental data using the software of the Photocor-Complex and DT-1202 spectrometers made it possible to obtain of the size distribution histograms for silicon dioxide colloidal particles in a standard sample. For the first time it has been established that the optimal parameters for measuring the size of colloidal SiO2 particles by the photon-correlation spectroscopy are the substance concentration less than 1 %, the photodetector position angle of 90 degrees and the number of measurements in a cycle of 100 – 150, and for the acoustic spectroscopy – 1 % substance concentration.
Keywords: photon correlation spectroscopy of dynamic light scattering, acoustic spectroscopy, colloidal particles.
2. THE THEORY OF NANOSYSTEMS — page 243
Aref`eva L.P., Shebzukhova I.G.
The influence of surface and interphase characteristics on the behavior of the phase diagram of nanoparticles of the paladium-platinum alloy — page 243
Abstract: The melting and crystallization temperatures have been calculated and the phase diagram of Pd – Pt metal particles of 10 nm in size has been constructed. The surface and interfacial energies, their temperature and size dependences were estimated by a modified electron-statistical method. It was found that the form of the phase diagram for Pd – Pt nanoparticles has significant differences from the diagram of bulk phases, including the melting-crystallization hysteresis.
Keywords: size effects, melting temperature, crystallization temperature, phase diagram, melting-crystallization hysteresis, binary nanoparticles, palladium-platinum system.
Malyshev M.D., Pakhomov P.M., Komarov P.V.
Using of sticky sphere model for qualitative reproduction of basic phase transitions of cysteine-silver solution — page 252
Abstract: In this work, the previously formulated mesoscopic model of a cysteine-silver solution, in which silver mercaptide clusters are considered as hard «sticky» spheres, is implemented on the basis of the LAMMPS software package. The key parameter that has a direct impact on the morphology of the forming aggregates and the behavior of the system depends on the salt concentration. The test calculations show that the constructed model can reproduce the stage of the maturation, the formation of the fibers of the gel-network and the coagulation of the cysteine-silver solution at the mesoscale level.
Keywords: silver mercaptide, hydrogel, supramolecular system, supramonomer, mesoscopic modeling, coarse-grained model.
Myasnichenko V.S., Sdobnyakov N.Yu., Bazulev A.N., Ershov P.M., Davydenkova E.M.
Size dependences of linear expansion and volume elasticity of mono- and bimetallic nanoclusters — page 260
Abstract: A series of molecular dynamics experiments on cooling disordered Au, Cu, Al, Ti metal nanoparticles and Au – Cu, Ti – Al bimetallic nanoalloys using the tight-binding potential have been performed. The size dependences of the temperature coefficient of linear expansion and the elasticity modulus for mono- and bimetallic particles are obtained. In the first approximation, the size dependence of the linear expansion coefficient is inversely proportional to the corresponding dependence for the melting temperature of a nanoparticle, which correlates with an analytical model. Molecular dynamics results predict a more moderate relative increase in the linear expansion coefficient compared to the analytical model. It was found that the modulus of elasticity increases with decreasing the nanoparticle size.
Keywords: bimetallic nanoparticles, molecular dynamics, tight-binding potential, linear expansion coefficient, bulk modulus, size dependence, approximation.
Myasnichenko V.S., Ershov P.M., Bogdanov S.S., Savina K.G., Matrenin P.S., Sdobnyakov N.Yu.
Crystallization of bimetallic nanoparticles: effect of atomic size mismatch and external pressure — page 274
Abstract: In this work, molecular dynamics simulation is carried out of crystallization of bimetallic Co – Au nanoparticles from the melt with various compositions. The effects of the dimensional mismatch between the atomic radii and external pressure on the final configurations cooled up to the temperature 100 K was studied. It was found that the specific potential energy for the bimetallic Co – Au nanoparticle increases with an increase in external pressure. Besides, as the external pressure increases, structural changes occur, namely, the average number of icosahedral atoms inside the cluster changes in a nonlinear character. The dependence of the specific potential energy of bimetallic Co – Au nanoparticles of various compositions on the coefficient of the dimensional mismatch ξ is more complex. The minimum for the gold-enriched composition and equiatomic composition is observed at the values ξ = 1,09 and ξ = 1,15, respectively.
Keywords: bimetallic nanoparticles, molecular dynamics, structural transformation, icosahedron, external pressure, size mismatch.
Pyansin D.V., Pan’kin N.A., Chaldyshkin A.N., Chistyakov N.I.
To the problem of determining the coefficient of thermal expansion of materials — page 284
Abstract: An experimental study and computer modeling in the ANSYS software package of the thermal effect on a metal material was carried out. A decrease in the values of the coefficient of the thermal expansion is noted with an increase in the heating rate of the sample. It is shown that this behavior is due to the presence of the temperature gradient between its central and surface parts. Good agreement of the results of computer simulation with the corresponding experimental data is found. The values of the coefficient of thermal expansion are close to true ones determined at low heating / cooling rates or with long exposure of the sample at the final and initial temperatures. The simulation results in ANSYS can be used to interpret and predict thermal properties of metallic materials.
Keywords: coefficient of thermal expansion, modeling, heating rate, temperature gradient, experiment.
Romanovskii V.I., Kolosov A.Yu., Khort A.A., Myasnichenko V.S., Podbolotov K.B., Savina K.G., Sokolov D.N., Romanovskaia E.V., Sdobnyakov N.Yu.
Features of Cu – Ni nanoparticle synthesis: experiment and computer simulation — page 293
Abstract: Combination of experiment and computer simulation made it possible to study the features of the process of Cu – Ni nanoparticle synthesis. Nanoparticles are synthesized by the method of exothermic combustion in solutions. The X-ray phase analysis of the obtained materials showed that all samples are pure bimetallic nanopowders with a distorted cubic crystal structure of each metal. The Monte-Carlo method in the temperature range from 300 to 6500 K established regularities of the neck formation for two cases of the initial location of copper and nickel nanoparticles: direct contact and relative displacement by 0,2 nm. The possibility of close integration of crystal structures as a Cu and Ni nanoparticles interaction result is shown.
Keywords: Cu-Ni, coalescence, computer simulation, Gupta potential, Monte-Carlo method, solution combustion synthesis.
Samsonov V.M., Talyzin I.V.
To the problem of stability of nanoscale island films and extended films with nanosized thickness — page 310
Abstract: The geometric instability of nanoscale island films is interpreted as a manifestation of the solid state wetting phenomenon, and instability of continuous extended films with nanosized thickness as a consequence of the solid state dewetting. Using molecular dynamics experiment, regularities and mechanisms are investigated of spreading of Pb solid nanoparticles on different Cu faces at a temperature 10 K below the melting temperature of nanoparticles of the chosen size (10 nm). The results obtained in molecular dynamics experiments are compared with experimental data for Pb microparticles of 5 – 10 μm in size. It has been also established that in the same «island – substrate» system both solid state wetting and solid state dewetting phenomena can simultaneously take place.
Keywords: island films, extended films with nanosized thickness, solid state wetting, solid state dewetting, molecular dynamics.
Shebzukhova I.G., Aref`eva L.P.
Estimation of the polarization and dispersion corrections to the surface energy of the faces of metal crystals — page 319
Abstract: On the basis of the electronic statistical method, expressions for the dispersion and polarization corrections to the surface energy of the crystal faces IA of metals at the boundary with vacuum are obtained and their value are calculated. Both corrections are highly anisotropic. The dispersion correction increases the surface energies of the faces (from 3 to 23 %), the polarization correction reduces them by less than 1 %. Taking into account these interactions improves the agreement between the calculated surface energy and the experimental data of the melts.
Keywords: surface energy, dispersion interaction, ion polarization, alkali metals, electronic statistical method.
3. FIRST PRINCIPLES AND ATOMISTIC MODELING — page 326
Belenkov M.E., Chernov V.M.
Ab initio calculations of the crystalline and electronic structure of 5-7 fluorographene varieties — page 326
Abstract: First-principle calculations of the structural and electronic properties of two new polymorphic varieties of fluorographene were performed using the density functional theory method. New layers of fluorographene can be formed during chemical adsorption of fluorine on the surface of 5 – 7 graphene layers. The structure of the layer of the first type is more deformed in comparison with the structure of the second type (deformation parameters DefT1 = 60,48° and DefT2 = 31,51°). Sublimation energies and band gaps are 13,85, 14,17 eV/(CF), and 4,09, 3,32 eV for CF – L5-7 layers of T1, T2 types, respectively
Keywords: graphene, fluorographene, ab initio calculations, crystal structure, electronic properties, polymorphism.
Belov A.N., Turovtsev V.V., Orlov Yu.D.
Measures of the basis efficiency in the internal rotation problem — page 338
Abstract: Definition of the variational limit for the Schrodinger torsion equation solution was considered. Energies of levels and transitions at the variational limits were calculated for different basis sets. With many modeling potentials it was shown that the quantity of reliable calculated levels linearly depends on the number of the basis functions. This number (the number of the maximum reliable state) was recommended as a measure of the basis efficiency. The slope of the straight line for the planar wave basis dependence is approximately equal to 1,03.
Keywords: internal rotation, Schrodinger torsion equation, basis function, basis efficiency, planar waves.
Belyaeva I.N., Kirichenko I.K., Ptashnyi O.D., Chekanova N.N., Yarkho T.A.
Normalization of classical hamiltonian systems with two degrees of freedom — page 348
Abstract: The family of the Hamiltonian systems with two degrees of freedom was investigated. The calculations of the Poincaré sections show that with arbitrary values of the parameters of the Hamilton function, the system is non-integrable and dynamic chaos is realized in it. For the three parameter sets, the system in question was found to be integrable, but shows that in one integrable case on the potential energy surface (PES) there are regions with the negative Gaussian curvature. It was found that in one integrable case for the same values of the parameters, the potential energy surface has a region with the negative Gaussian curvature. At the same time, in the other two cases, the domains with negative Gaussian curvature are not integrable for the corresponding values of the parameters. Thus, the presence of regions with negative Gaussian curvature on the potential energy surface is not enough for the development of the global chaos in the system. The classical normal form for arbitrary parameter values is obtained.
Keywords: Hamiltonian systems, normalization, computer modeling, potential energy surface.
Belyakova R.M., Polukhin V.A.
Hydrogen permeability through tantalum alloys allowed with Nb and W — page 356
Abstract: An analysis of studies of membrane alloys Ta77Nb23 and Ta94,9W5,1 was carried out with an estimation of their characteristics – thermal stability, strength – by measuring microhardness, matrix structure – by X-ray analysis, as well as the dynamics of hydrogen – diffusion (theoretically) and permeability (experimentally). The efficiency of the hydrogen separation/purification using the Ta77Nb23 and Ta94,9W5,1 alloys was higher than that of palladium, measured under the same test conditions.
Keywords: hydrogen selective membranes, tantalum-based alloy, solubility, absorption, permeability, diffusion, concentration, gas separation, purification, embrittlement, thermal stability, resistance to hydrogen embrittlement.
Vysotsky Yu.B., Kartashynska E.S.
pKA change of saturated carboxylic acids and amines during their dimerization at the air/water interface. Quantum-chemical approach — page 370
Abstract: A theoretical approach to the pKA assessment for dimers of saturated carboxylic acids CnH2n+1COOH (n = 6 – 16) and amines CnH2n+1NH2 (n = 6 – 16) at the air/water interface is proposed. The model is based on calculation of the formation and dimerization Gibbs energies of the surfactants in neutral and ionized form in the water and gas phases. The calculations are done using semi-empirical quantum-chemical methods РМ3 and РМ6 within the framework of the conductor-like screening model (COSMO). It is shown that the dimer formation with one ionized and one neutral surfactant molecules is the most energetically favorable. The surface pKA value for surfactant dimers is found to depend on their surfactant chain length.
Keywords: dissociation, aliphatic amines, carboxylic acids, pKA , enthalpy, entropy, dimerization Gibbs energy, semi-empirical methods.
Gafner Yu.Ya., Gafner S.L., Kulikova Yu.A.
Some new results of modeling the processes of the gas-phase synthesis of Cu – Au nanoparticles — page 384
Abstract: Simulation of synthesis of binary Cu – Au nanoclusters from a high-temperature gas medium by the condensation method was carried out by the molecular dynamics method based on the tight-binding potential. The initial configuration consisted of 91124 Cu and Au atoms was located randomly in space with the target chemical composition Cu3Au, CuAu, Cu90Au10 and Cu60Au40. It was found that in the cases of the stoichiometric chemical composition of the initial gas mixture (CuAu or Cu3Au), very small clusters with an overwhelming content of gold atoms were observed. It was also shown that many nanoparticles obtained by this synthesis had a five-particle structure. It is assumed that the reason for such an arrangement of atoms in the compounds under study may be the size mismatch of gold and copper atoms, leading to «loosening» of the crystal lattice.
Keywords: nanotechnology, nanopowders, computer simulation, tight-binding potential, nanoparticles, copper, gold.
Gvozdenko A.A., Blinov A.V., Yasnaya M.A., Golik A.B., Raffa V.V., Kramarenko V.N., Maglakelidze D.G., Shevchenko I.M.
Computer quantum-chemical simulation of multicomponent SiO2 – MexOy systems — page 394
Abstract: For the first time, in this work, the possibility of forming multicomponent SiO2 – Fe3O4, SiO2 – MnO2 and SiO2 – CuO systems by adsorption of a metal oxide layer consisting of nanoparticles of manganese (IV) dioxide, mixed iron oxide or nanoparticles of copper (II) oxide on the surface of SiO2 microspheres has been shown by means of a computer quantum-chemical simulation. According to the results of the scanning electron microscopy, it was found that formation of a metal oxide layer in the SiO2 – Fe3O4 sample occurred most uniformly among all the presented samples of multicomponent systems. Within the framework of quantum-chemical simulation, it was found that the most energetically favorable and stable was the interaction of SiO2 with Fe3O4 nanoparticles.
Keywords: nanocomposites, multicomponent systems, quantum-chemical simulation, sol-gel method.
Greshnyakov V.A., Belenkov E.A.
Structure and stability of a tetragonal diamond-like layer: first-principle calculations — page 405
Abstract: Using the density functional theory method, a theoretical study of a novel layered DL4-8 polymorph of diamond, consisting of two polymerized tetragonal graphene L4-8 layers, was performed. It was established that the new diamond-like layer has a two-dimensional tetragonal lattice with the parameter a = b = 0,3822 nm and a thickness of 0,1599 nm. The calculated surface density and band gap of this layer are 0,109 μg/cm2 and 2,63 eV, respectively. The new DL4-8 layer must be stable up to at least K. It was also found that the layer can be obtained by strong uniaxial compression of two graphene L4-8 layers at a pressure of 29,6 GPa.
Keywords: graphene, diamond-like layer, ab initio calculations, crystal structure, phase transitions.
Zhuravkov M.A., Nagorny Yu.E., Politaev D.N.
Comparative analysis of results of numerical modeling of mechanical behavior of graphene and silicene in the frames of common harmonic field — page 415
Abstract: The article presents the results of application of the general harmonic field model for numerical modeling of mechanical properties of samples of graphene and silicene nanostructures similar in geometric form. A calculation of the stiffness coefficients of the elements for this model was made based on the stiffness of a pair of basic ones through the natural frequencies of oscillations of three-node fragments. Dependencies of elastic modules on linear dimensions for examined samples are given. In both cases, there is an increase in the modulus of longitudinal elasticity with an increase in asymptote with an increase in the length of the sample and a very weak dependence on its width. The coefficient of transverse strain decreases as the width increases. Increasing the length gives graphene an increase in this indicator, and in silicene – its decrease.
Keywords: general harmonic field, graphene, silicene, elastic coefficients, natural frequencies of oscillations, Young’s modulus, Poisson’s coefficient.
Ivanov D.V., Vasilyev S.A., Sdobnyakov N.Yu., Romanovskaia E.V., Anofriev V.A., Koshelev V.A., Antonov A.S.
Simulation of the fractal metal films formation — page 424
Abstract: In this work, molecular dynamics method and the tight binding potential was used to simulate the process of the molecular beam epitaxy in order to determine regularities in the formation of fractal metal films on a solid surface. Copper was used as a substrate, the film was formed from gold atoms. The possibility of formation of fractal structures in an island gold film on the copper surface is shown. Various analytical methods using the Gwyddion software product have used to analyze a range of changes in the fractal dimension under different conditions of molecular dynamics experiment.
Keywords: molecular beam epitaxy, molecular dynamics modeling, tight-binding potential, fractal dimension, gold, copper.
Kotomkin A.V., Rusakova N.P., Turovtsev V.V., Orlov Yu.D.
Electron parameters of the structural isomers of k,k-difluorooctane — page 438
Abstract: The investigation of the electronic structure of the 6,6-difluorine undecane (6,6 – F2C11H22) and structural isomers of k,k-difluorine octane molecules (k,k – F2C8H16, 1 ≤ k ≤ 8, where k is a position of the fluorine atoms in alkyl chain) has been carried out. Within the «quantum theory of atoms in molecules» the transferable or «standard» electron parameters of topological atoms and atomic groups (charge, energy and volume) have been determined. The inductive effect spread from the fluorine and the fluorine-containing fragments (CHF2 and CF2) on local environment was explored. The influence of CHF2 applies to four CH2 groups along the hydrocarbon chain, the influence of CF2 applies to two CH2 groups in both sides along the hydrocarbon chain. Data on changes in electronic parameters depending on the distance from the fluorine atom were obtained. Series of electronegativity of the functional groups has been made up. According to it CF2 group is a stronger acceptor of electron density, than CHF2.
Keywords: inductive effect, electronegativity, quantum theory of atoms in molecules, electron density, fluorine alkanes.
Mavrinskii V.V., Belenkov E.A.
Graphyne layers formed on the basis of 5 – 7 graphene layers — page 446
Abstract: The geometrically optimized structure of 43 new polymorphic varieties of L5-7α graphyne layers modeled on the basis of layers 5 – 7 of graphene has been calculated by the method of MM2 molecular mechanics. It was found that 3 polymorphic varieties of α type and 20 varieties of β and γ types are possible. The γ1 – L5-7α is the most stable layer since it has the minimal deformation parameter Def = 9,0°. Practical applications of new graphyne polymorphs can be used for molecular sieves or hydrogen adsorbents.
Keywords: graphene, graphyne layers, hybrid carbon compounds, polymorphism, two-dimensional nanostructures, polymorphism, crystal structure.
Polukhin V.A., Sidorov N.I., Belyakova R.M.
Hydrogen permeability of amorphous, nano- and crystalline alloys based on iron and nickel — page 457
Abstract: The kinetics of hydrogen permeability and diffusion in hydrogenated membrane alloys based on Fe and Ni have been investigated, which have functional characteristics, structural strength and thermal stability, and are a promising alternative to expensive palladium alloys. The strength characteristics, thermal stability and resistance to hydrogen embrittlement have been studied. The mechanisms of structuring, diffusion and permeability of hydrogen in crystalline, amorphous, nanocrystalline states are considered. For membrane alloys, a particularly important aspect is the combination in open structures (amorphous and bcc), while for hydrogen accumulation, in addition to transport channels (diffusion and permeability), high-density intermetallic clusters are also required. It is noted that, during long-term operation, due to the appearance of dense cluster configurations of intermediate ordering, which shorten the diffusion channels, the transport of hydrogen through them begins to decrease.
Keywords: membrane alloys, amorphous structure, interatomic bonds, clusters, hydrogenation, glass transition, sorption, diffusion, permeability, intermetallic compounds, hydrides, hydrogen energy, molecular dynamics.
Puitov V.V., Talyzin I.V., Vasilyev S.A., Samsonov V.M.
Generation of initial configurations of metal nanocluster isomers: algorithms and their approbation — page 474
Abstract: Algorithms for generating the initial configurations of icosahedral, decahedral and cuboctahedral nanoclusters have been developed and verified. Algorithms and corresponding computer programs have been approbated on the gold nanocluster isomers. Molecular dynamics was also employed to study the regularities of the thermally induced structural transformations in gold nanoparticles with the initial cuboctahedral configuration. It was found that the melting of cuboctahedra is preceded by their transition into icosahedral isomers.
Keywords: nanoparticles, icosahedrons, decahedrons, cuboctahedrons, generation algorithms, gold nanoclusters, molecular dynamics, thermally induced structural transformations.
Gafner Yu.Ya., Ryzhkova D.A.
Thermal stability of small fcc-magic size silver clusters structure with the initial amorphous configuration — page 486
Abstract: Silver particles smaller than the wavelength of visible light are capable of absorbing light to a large extent due to the surface plasmon resonance, the frequency and intensity of which depend on the shape and structure of nanoparticles. In other words, control of the structure of Ag nanoclusters, widely used in plasmonics, makes it possible to control the wavelengths of light that they scatter and absorb. This article discusses the issue of thermal stability of small Ag clusters with the number of atoms corresponding to the «magic» numbers of the fcc structure, with the initial amorphous configuration of the clusters. It has been shown that the initial amorphous morphology of particles can significantly change the nature of the structure formation of Ag nanoclusters: the formation of a stable fcc structure is replaced by a transition to Dh- and Ih- configurations.
Keywords: nanoclusters, silver, structure, computer simulation, tight-binding, molecular dynamics, fcc configuration, amorphous morphology.
Ryashentsev D.S., Belenkov E.A.
Investigation of new polymorphic varieties of boron nitride with diamond-like structures — page 493
Abstract: The article presents a theoretical study of new polymorphic varieties of boron nitride with diamond-like structures. As a result of calculations by the density functional theory method in the gradient approximation, the possibility of stable existence of four new structural varieties of boron nitride: BN – LA4, BN – LA5, BN – LA6, and BN – LA7 was established. The sublimation energy of new BN phases varies in the range from 16,85 to 17,84 eV/(BN), the band gap is from 4,34 to 6,07 eV. The bulk density of polymorphs varies from 3,020 to 3,452 g/cm3.
Keywords: boron nitride, diamond-like phases, ab initio calculations, crystal structure, electronic properties, polymorphism.
Sdobnyakov N.Yu., Myasnichenko V.S., Savina K.G., Kolosov A.Yu., Veselov A.D., Bazulev A.N., Grigoryev R.E., Sokolov D.N.
Study of internal nanoporous structure and external surface of bimetallic nanoparticles — page 504
Abstract: Exemplifying on two bimetallic nanoparticles Cu – Pt and Au – Ag, the internal structure and external surface has been investigated in the process of dealloying. Equiatomic compositions with the total number of atoms Ntot = 3000 are considered. In the dealloying process half of both the copper and silver atoms were removed. The Monte Carlo method within the Metropolis scheme is used as a simulation method. The interatomic interaction was described by the tight-binding potential. As it was expected, the selective corrosion leads to the fact that the surface layer of the particle is enriched with one of the components atoms. However, the particle core retains the structure of the binary nanoalloy. We also found that as a result of the selective corrosion, a defective structure of the nanoparticle is formed. Accordingly, we assume that it is these defects (mainly vacancies) that lead to the porous structure of larger binary nanoparticles observed in experiments on the dealloying. A change in the specific surface area per unit volume or weight affects the adsorption and catalytic properties, as well as the corrosion resistance of bimetallic nanoparticles.
Keywords: dealloying phenomenon, binary metal nanoparticles, Monte-Carlo method, defect, porosity, nanoalloys.
4. PHYSICAL AND CHEMICAL BASES OF NANOTECHNOLOGIES — page 516
Bazzal K., Alekseenko N.A., Voropay E.S., Kovalenko M.N., Patapovich M.P., Zajogin A.P.
Spectral studies of the Al2O3 and AlN nanopowder formation exposed aluminum by a series of twin laser pulses in the air atmosphere — page 516
Abstract: A study of the Al2O3 and AlN nanopowder formation under the influence of twin laser pulses with an energy of 52 mJ and between the pulse interval of 10 microseconds on an aluminum target placed in a closed glass rectangular box, depending on the number of pulses. It was found that the highest intensity of the bands of AlO suboxide and AlN molecules is observed at 40 – 50 consecutive double pulses in a series. The size of the primary particles estimated using the high-resolution electron microscopy was mainly 30 – 40 nm, the particles were collected in agglomerates. The possibility of obtaining active forms of aluminum oxides and products of their interaction with oxygen and air nitrogen in a laser plasma deposited on a glass surface is shown by RAMAN methods.
Keywords: oxidized nanopowders Al, Al2O3, AlN, AlO suboxides, pulsed laser sputtering, laser plasma, laser spark spectrometry, multicharged ions, dual laser pulses.
Bogdanova E.A., Skachkov V.M.
Investigation of rheological properties of hydroxyapatite and fluorapatite in colloidal state — page 525
Abstract: The article discusses the possibility of practical application of a suspension of hydroxyapatite and fluorapatite as components of medicines, pharmaceutical compositions, and biomaterials. Their viscosity, density and degree of dispersion were estimated by using the physical and chemical analysis methods. The concentration intervals in which the studied systems have the properties necessary for creating pharmaceutical compositions and biomaterials are determined. The biological activity of apatites largely depends on the degree of dispersion and manifests itself the more, the smaller the size of their particles, and the obtained in this work nanoparticles of hydroxyapatite and fluorapatite in suspensions have a particle size of the order of less than 100 nm, and, consequently, their rheological properties will be most fully manifested.
Keywords: hydroxyapatite, fluorapatite, rheological properties, biomaterials.
Bogdanova E.A., Veretennikova I.A.
Investigation of sintering features of ceramic materials based on hydroxyapatite and its substituted forms — page 535
Abstract: Stoichiometric and fluorsubstituted hydroxyapatite powders with increased sintering activity (the initial compaction temperature is 600 °C) were synthesized by precipitation from solutions. Properties of synthesized powders and ceramics after firing were investigated. It is shown that the introduction of fluoride ions can thermally stabilize the apatite phase to a temperature of 1000 °C, increase the degree of dispersion and the specific surface area, and almost three times increase the microhardness of the material. Comparison of the particle size distribution in synthesized powders and the grain distribution in sintered ceramics confirmed that ceramics inherited the nanostructure of the original powders.
Keywords: hydroxyapatite, fluorsubstituted hydroxyapatite, sintering, bioceramics.
Bolotov A.N., Novikova O.O., Novikov V.V.
Silicone magnetic nanofluids adapted for the conditions of boundary friction — page 546
Abstract: Currently known magnetic lubricant nanofluids have insufficiently good tribological characteristics when operating in the boundary friction mode. An adaptation method is proposed for the boundary friction of magnetic siloxane nanofluids by modifying their composition with chemically active antifriction, antiwear and extreme pressure additives. A number of lubricating compositions of magnetic nanofluids based on polyethylsiloxane PES-5 have been created. Conducted experimental studies have shown that the most significant improvement in the antifriction and antiwear properties of nanofluids is achieved with the introduction of Sovol and 3N2TE chlorine additives into their structure. Adding to the nanofluid the antioxidant additive DF-11, the fluorine-containing additive
EO-1, the metal-plating compound MKF-18 did not lead to a significant improvement in the antifriction properties. It has been established that magnetic nanofluids with modifying additives are comparable in tribological properties with traditional non-magnetic liquid lubricants and are superior to plastic lubricants based on polyethylsiloxane. The developed compositions based on siloxane nanofluids will be in demand for lubrication of rolling and sliding bearings, gears, contact seals, which operate at low and elevated temperatures in a gas environment or in a vacuum. Most successfully, they can be used in vacuum and space technology, for magnetic frictional units, where only one refueling with a limited amount of lubricant is possible.
Keywords: magnetic lubricant nanofluid, boundary friction, wear, lubrication, anti-friction and anti-wear additives.
Bolotov A.N., Novikova O.O.
Mobile magnetometer for rapid test of saturation magnetization of magnetic nanofluids — page 557
Abstract: The work is aimed at creating a magnetometric device for accurate determining the saturation magnetization of magnetic nanofluids and similar properties of functional dispersed materials. The device is based on a magnetometric method with the Hall induction transducers, improved taking into account the peculiarities of the physical and mechanical properties of liquids. The measuring magnetic system of the device is designed in such a way that with the help of permanent magnets it is possible to create a uniform magnetizing field up to (2 ÷ 4) · 105 A/m in a working gap where the cuvette with the studied magnetic nanofluid is installed. Under the cuvette with a magnetic nanofluid in its middle section is a Hall Converter, which serves to measure the strength of the magnetizing magnetic field. The second Hall Converter, designed to measure the magnetic field induction in a substance, is installed in a rectangular groove and is located in the center of the magnetic nanofluid in the cuvette. The relative error of measuring the magnetization on the device did not exceed 2 % for magnetic nanofluids with a magnetization in the range from 10 kA / m to 50 kA/m. The created device can be used for Express measurements in laboratory and industrial conditions and does not require special professional skills. It is shown that the additive component of the instrumental measurement error depends on the values of the residual voltage (nonequipotential EMF), side galvanomagnetic effects and thermo – EMF of the measuring Converter. The multiplicative component is related to the time and temperature instability of the conversion coefficient and the current or voltage supply. The methodic error of the magnetometer is caused by the fact that not a fully closed magnetic circuit is used for measuring the magnetic field induction. It is shown that the device meets international standards for magnetic measurements of soft magnetic materials in terms of their metrological parameters. The device allowed us to determine the magnetization of colloidal systems in magnetic fields of a start paraprocess, individual magnetization of nanoparticles of the dispersed phase, the aggregative stability of colloids in magnetic and gravity fields to estimate the size of the solvation shell of the nanoparticles.
Keywords: magnetic nanofluid, saturation magnetization, Hall converters, magnetic system, measurement error, numerical simulation.
Giniyatullin I.M., Bogdanova E.A., Nefedova K.V.
Development of composite materials based on nanoscale hydroxyapatite reinforced with aluminum and zirconium oxides — page 571
Abstract: The article discusses the possibility of strengthening nanostructured hydroxyapatite obtained by precipitation from a solution by introducing reinforcing additives of aluminum oxide and zirconium oxide. The influence of the amount of the added additive and the annealing temperature on the linear shrinkage, morphology and microhardness of the material was evaluated. It was found that the sample has the maximum strength characteristics, a dense uniform structure with a high degree of crystallinity Ca10(PO4)6(OH)2 – 15%Al2O3 – 5%ZrO2. The composite of this composition is a promising material for further research in order to introduce it into medical practice.
Keywords: hydroxyapatite, composite biomaterials, microhardness.
Davydova A.A., Raksha E.V., Oskolkova O.N., Gnatovskaja V.V., Sukhov P.V., Padun O.M., Glazunova V.A., Burkhovetskij V.V., Volkova G.K., Berestneva Yu.V., Savoskin M.V.
Few-layer graphene particles based on thermally expanded cointercalate of graphite nitrate with acetic and formic acids — page 580
Abstract: Dispersions of graphene nanoparticles were obtained by liquid phase exfoliation of thermally expanded graphite in ethanol as well as tert-butanol via sonication. Initial thermally expanded graphite was obtained by heat treatment in the shock mode of ternary graphite nitrate intercalation compound with formic and acetic acids. Investigation of the graphite nitrate intercalation compound and thermally expanded graphite structural characteristics by X-ray diffraction analysis has been carried out. The microstructure and morphology of the obtained graphene particles were studied by transmission electron microscopy.
Keywords: thermally expanded graphite, few-layer graphene particles, graphite nitrate, cointercalation, X-ray diffraction analysis, transmission electronic microscopy.
Devitskiy O.V., Kravtsov A.A., Pashchenko A.S., Sysoev I.A.
Influence of thermal annealing on the structure and optical properties of thin aluminum nitride films on sapphire — page 591
Abstract: The results of an experimental study of the effect of thermal annealing on the structure, surface morphology and optical properties of thin films of aluminum nitride on sapphire are presented. Thin films of aluminum nitride on sapphire with a thickness of 200 nm were annealed in air and in a nitrogen atmosphere at a residual gas pressure in the vacuum chamber of the ion-beam deposition unit of no less than 100 Pa at a temperature of 850 °C. It was found that thermal annealing of aluminum nitride films on sapphire in a nitrogen atmosphere leads to a decrease in the root mean square roughness of the films to 0,8 nm, an increase in the transmittance in the wavelength range of 300 ‑ 1100 nm up to 96 %, and an increase in the stoichiometry of the films. It is shown that for aluminum nitride films annealed in air on sapphire, aluminum nitride is oxidized to form amorphous aluminum oxide at a temperature of 850 °C. The results of energy dispersive analysis showed the complete absence of nitrogen on the surface of these films. A decrease in the transmittance over the entire wavelength range for films AlN annealed in air makes them unsuitable for use in optoelectronics. The surface morphology of these films is an array of pointed formations with a maximum height 190,7 nm and an arithmetic mean surface roughness 3,7 nm.
Keywords: aluminum nitride, ion-beam deposition, thermal annealing, nanoheterostructures, sapphire, optical properties, energy dispersive analysis.
Zernitsa D.A., Shepelevich V.G.
The structure formation of rapidly solidified foil of the eutectic alloy Sn – 8,8 wt. % Zn — page 601
Abstract: The results are presenred of a study of the microstructure of rapidly solidified foil of the eutectic alloy Sn – 8,8 wt.% Zn A and B surfaces, microstructure parameters are determined. The texture of the precipitates of tin and zinc solid solutions in the foil was studied, and the pole densities of the diffraction lines of these phases are presented. The effect is studied of ultrafast cooling on the distribution of misorientation angles of neighboring and randomly selected grains for surface foil layers in contact with surfaces A and B.
Keywords: rapidly solidification, Sn – Zn alloy, eutectic, microstructure, texture, spinodal decomposition, disorientation, twinning.
Izmailov V.V., Novoselova M.V.
Some statistical distributions, which describe the nanotopography of technical surfaces — page 609
Abstract: The nanotopography of engineering surfaces of machine parts made of high alloy heat-treated steel and electric silver after finishing mechanical treatment was studied. The probability density functions of the nanotopography parameters – the heights of peaks and the radii of curvature of their vertices – were experimentally determined. These parameters are necessary for theoretical description of processes of the contact interaction of engineering surfaces (exemplifying on surfaces of silver and steel). It is established that the distributions of the above mentioned nanoroughness parameters are essentially asymmetrical and are far from normal ones. It has been proved that for the studied surfaces the probability densities of the above mentioned nanoroughness parameters are adequately described by the beta-distribution. The validity of this conclusion is confirmed by the fitting criteria such as χ2 (K. Pearson’s criterion) and Romanovsky’s criterion.
Keywords: surface, nanotopography, parameters, probability density, beta-distribution, fitting criteria.
Kravtsov A.A., Devitskiy O.V., Kuleshov D.S., Pashchenko A.S.
The microstructure of polymer functional coatings with silver nanoparticles for solar cells — page 617
Abstract: Within the framework of this study, functional polymer coatings with silver nanoparticles were obtained on the surface of silicon solar cells. The size of the nanoparticles used to create the coatings was ~100 nm. For the first time, the microstructure of the obtained coatings was investigated by scanning electron microscopy. It was shown that nanoparticles have a sufficiently high and uniform distribution density in the coating. In the coatings obtained using the drying method, that there are single defects in the form of the absence of a film. These defects are presumably due to differences in microrelief on the surface of solar cells and can be eliminated by reapplying the film. Experimental studies of the quantum yield of photoconverters have shown that functional coatings based on polymers with silver nanoparticles can significantly improve the characteristics of silicon solar cells.
Keywords: olar cells, silver nanoparticles, functional coatings, microstructure, polyvinyl butyral, morphology, plasmon resonance, efficiency increase, quantum yield.
Malinskiy T.V., Mikolutskiy S.I., Rogalin V.E., Khomich Yu.V., Yamshchikov V.A., Kaplunov I.A., Ivanova A.I.
Modification of silicon surface under influence of radiation of a nanosecond ultraviolet laser — page 628
Abstract: The effect of radiation of a nanosecond ultraviolet laser (λ = 355 nm, pulse duration 10 ns, pulse energy up to 8 mJ, pulse repetition rate – up to 100 Hz) on a silicon single crystal has been investigated by methods of the optical profilometry and scanning electron microscopy. At an energy density of ≥ 1,2 J/сm2, formation of the plasma torch and crater was observed. At an energy density of ≥ 0,2 J/сm2, pockets of microbreakdown appeared on processing defects, and traces of uncontrolled surface uplift were recorded. Irradiation with a scanning laser beam at an energy density of 0,2 J/сm2 forms microcraters on a surface with a size of several microns. With an increase in the energy density, the size of the microbreakdowns increased, and at an energy density ≥ 0,7 J/сm2, the impact of the scanning beam forms a continuous damage zone.
Keywords: laser impact, silicon single crystal, UV laser, nanosecond pulse, micro- and nanomodification of the surface, plastic deformation.
Malkanduev Yu.A., Kokoevа A.A.
Investigation of optical properties of water-soluble electrolytes based on α-amino acids — page 637
Abstract: It is known from literature that L-amino acids, in addition to glycine, are optically active substances and have the ability to rotate the polarization plane of a polarized light beam passing through it to the left side. The paper presents the synthesis and radical polymerization of water-soluble polyelectrolytes based on L-valine and L-leucine. This paper describes a method for obtaining new nanocompositional materials based on synthesized polymers and modified montmorillonite. The optically active properties were investigated and the value of the specific rotation of the polarization plane for the alkylated amino acid – N,N-diallylvaline and N,N-diallylleucine was determined.
Keywords: amino acids, radical polymerization, alkylation of amino acids, nanocomposites, modified clay, optical activity, specific rotation of the polarization plane, rotation angle.
Malyshkina O.V., Ivanova A.I., Patsuev K.V.
Effect of the synthesis temperature on the structure of sodium-lithium niobate ceramics — page 644
Abstract: The authors synthesized samples and studied the structure of piezoelectric ceramics based on sodium and lithium niobates (Li0,1Na0,9)NbO3 with various technologies for the synthesis of sodium niobate material. A comparative study of the structure and dielectric properties of the obtained samples was carried out.. A significant dependence of grain formation during sintering of the samples on the synthesis temperature of the NaNbO3 composition is shown. It was found that the temperature of the phase transition strongly depends on the temperature of the first synthesis of the sodium niobate (Tmax ~ 375 °С if the first synthesis temperature was 650 °С; Tmax = 425 °С if the first synthesis temperature is 700 °С).
Keywords: piezoelectric ceramics, lead-free materials, grain structure.
Malyshkina O.V., Ivanova A.I., Karelina K.S., Petrov R.A.
Structure features of barium and calcium titanate ceramics — page 652
Abstract: Samples of ceramics based on barium titanate and calcium titanate were obtained and studied. We have analyzed the elemental composition of the obtained composite. It is shown that calcium-barium titanate Ba1-xCaxTiO3 solid solution contains calcium with x < 0,3. In ceramic samples with x ≥ 0,3, an excess of CaTiO3 was recrystallized in individual grains. An increase in the concentration of calcium leads to both a decrease in the size of the samples and a decrease in its density. An increase in the grain size (by several times) of the BaTiO3 ceramics in comparison with the CaTiO3 ceramics leads to a corresponding increase in the microhardness of the samples.
Keywords: barium titanate piezoelectric ceramics, lead-free materials, grain structure.
Mustafaev G.A., Mustafaev A.G., Panchenko V.A., Cherkesova N.V.
Development of a logical element based on polyphenylene molecules — page 662
Abstract: The high energy consumption of integrated electronics products and expensive methods of their production makes scaling silicon semiconductor devices to sizes less than 50 nm a difficult technological and design task. Recently, significant advances have been made in the development and research of molecular electronics products: molecular wires, molecular diodes made from individual molecules. Good results also obtained in the technology of forming a reliable electrical contact with electrically conductive molecules. Advances in nanoelectronics make it possible to develop more complex molecular electronic structures such as digital logic circuits. In this work, a quantum-chemical simulation of a molecule performing the function of a logical element is carried out, the equilibrium spatial configuration of the molecule is optimized, the design is developed and the topology of the layers for fabricating a substrate for mounting a molecule and creating external interfaces is developed. The obtained results demonstrate the promise of organic electronics as an alternative to silicon semiconductor materials in the development of integrated circuits.
Keywords: modeling, molecular electronics, logic element, nanoelectronics, molecular diode, digital logic, functional electronics.
Pan’kin N.A., Sigachev A.F., Mishkin V.P.
Investigation of pressing diagrams during molding a mixture of copper powders and silicon carbide — page 672
Abstract: A study of a mixture of copper and silicon carbide powders after one-sided cold forming in a closed mold was carried out by the next methods: scanning electron microscopy, hydrostatic weighing and analysis of pressing diagrams. The main stages of molding, their boundaries and characteristic processes occurring at each of them are identified. It was found that at least three areas can be distinguished in the molding diagram. It is shown that their boundaries (in terms of pressure) are determined by the mechanical properties of the materials of the used powders and the processes of redistribution / packing of structural elements and their elastic / inelastic deformation.
Keywords: copper, silicon carbide, pressing diagram, density, ultimate pressure, particle shape, forming mechanism.
Pasechnik L.A., Bibanaeva S.A., Medyankina I.S., Yatsenko S.P.
Mechanism and kinetics of neutralization of copper-containing solutions with modified red slurries of alumina production — page 681
Abstract: Methods for modification red mud (RM) by treatment with hydrochloric acid and by carbonization to obtain sorption materials for extracting metals from acidic solutions are proposed. Modification of the RM by carbonation increases the area and volume of pores in the carbonized red mud (CRM), that leads to a higher sorption capacity up to 246 mg/g with simultaneously neutralization of the copper solution from 1,5 to 4,5 pH. The acid treatment leads to less positive effects on the extraction of copper. The sorption kinetics is described by both pseudo-first-order (R2 > 0,96) and pseudo-second-order (R2 > 0,98) equations, which determine the equivalent contributions to the overall speed of the process of the mass transfer and the ion interaction stages. A mechanism was studied and it was found that surface diffusion processes at the «solid-liquid» interface turn into the mass transfer of Cu2+ ions and chemical interaction with functional groups on the surface and inside the particles of modified muds. For the initial mud, these processes are almost equivalent. Desorption of copper with water and a solution of ethylenediaminetetraacetic acid (EDTA) has shown that the strength of bonds in the structure of CRM–Cu and the stability of surface triple complexes Cu–EDTA–CRM are higher than for Cu–EDTA–RM. The potential have been demonstrated of creating sorption materials by used industrial waste, in particular alkaline red slurries, and their applications for the absorption of toxic metals from acidic wastewater for mutual neutralization and utilization of industrial waste from metallurgical industries – solid, gaseous and liquid.
Keywords: red mud, surface modification, acid treatment, carbonation, sorption, desorption, copper(II) ions.
Pereverzev D.I., Bogdanova E.A., Nefedova K.V.
Creating biocomposites based on nano-sized hydroxyapatite doped with zirconium oxide and calcium fluoride — page 697
Abstract: The article discusses the possibility of strengthening nanostructured hydroxyapatite (HAP) obtained by precipitation from a solution by introducing zirconium oxide and calcium fluoride. The influence of qualitative and quantitative composition on sintering processes and strength characteristics of investigated samples has been shown. It was found experimentally that the sample has the maximum strength characteristics and constant composition Ca10(PO4)6(OH)2 – 15%CaF2 – 5%ZrO2. The composite has a dense uniform structure with a high degree of crystallinity and is a promising material for further research in order to introduce it into medical practice.
Keywords: hydroxyapatite, composite biomaterials, microhardness.
Sverdlik G.I., Ataeva A.Yu., Ataev A.A.
Procedure for determining hydraulic jet barbotter resistance for collecting fine dust — page 706
Abstract: North Caucasian Institute of Mining and Metallurgy (State Technological University) has developed a design of a jet bubbler which is based on the patented design of the device main unit – a distribution plate, which allows to implement a foam mode in the bubbler. This dust collector allows you to capture small dust particles (<1 microns), including nanoparticles, that are not captured in bag filters. The article presents a method for calculating the hydraulic resistance of the bubbler, which is required for use, when selecting a fan for the process of dust collection in the bubbler. The hydraulic resistance of the bubbler is defined as the sum of the components: the static pressure of the liquid layer, the capillary drop in the zone of bubbles formation and the resistances of distribution plate parts. The developed method was used in the design of a process line for cleaning gases from pulverized ascents of waelz kiln of zinc production containing nanoparticles.
Keywords: hydraulic resistance, bubbler, bubbles, nanoparticles, capillary drop, surface tension.
Sinev I.V., Klychkov N.A., Timoshenko D.A., Simakov V.V.
Illumination effect on recognition ability of multisensor microsystems based on tin oxide nanowhiskers — page 713
Abstract: Using standard methods of data classification, the possibility of recognizing gas mixtures using a multisensor microsystem with a gas-sensitive layer based on whisker nanocrystals is shown. The statistical analysis of the experimental results showed that the illumination of a gas-sensitive layer of tin dioxide with a LED in the ultraviolet range significant increases the median Euclidean-Mahalanobis distance between the classes (recognition ability) of various gas samples compared to the results of measurements in the dark. Suggested that the increase in the recognition ability of a multisensor microsystem is associated with the selective effect of illumination on surface chemical reactions of oxygen species and particles of analyzed gases.
Keywords: tin dioxide, nanowhiskers, multisensor microsystems, ultraviolet illumination, recognition of gas mixtures.
Skachkov V.M., Pasechnik L.A., Yatsenko S.P.
Study of properties of diffusion-hardening composite solder GaSn – CuSn – Mo — page 722
Abstract: The article discusses the possibility of regulating the properties of a diffusion-hardening solder based on a low-melting gallium-tin alloy and a solid component consisting of a copper-tin alloy powder by introducing an inert metal molybdenum powder and heat treatment. The microhardness and thermal stability of composite diffusion-hardening solders were evaluated. It is shown that repeated heat treatment at high temperatures contributes to the transition of the solder to an equilibrium state, with a sharp increase in hardness, almost by an order of magnitude. It is confirmed that inert fillers reduce the mechanical strength relative to the initial diffusion-hardening solder, even those that are well wetted with gallium, but there is a certain range containing a certain amount of the inert component, for molybdenum powder it is 15%, at which the microhardness of the composite solder reaches the maximum.
Keywords: composite diffusion-hardening solders, structure, properties, microhardness, differential thermal analysis.
Timoshenko D.A., Sinev I.V., Simakov V.V.
Design of gas sensor based on tin oxide nanowhiskers — page 731
Abstract: Tin dioxide nanowhiskers were grown by the vapor deposition. The effect of technological parameters on the morphology of the grown nanostructures was investigated. It is shown that an increase in the partial pressure of oxygen in the range from 0,06 mbar to 9,3 mbar and the temperature of the deposition zone in the range from 940°C to 995°C leads to an increase in the diameter of the formed nanocrystals. Experimentally it was shown that the average diameter of nanowhiskers varied from 80 nm to 250 nm. A gas sensor was formed with an active layer, based on the nanocrystals, sensitive to acetone vapor. The value of the gas sensitivity and the characteristic times of the sensor are sufficient for practical use in gas analyzers and systems for recognizing gas mixtures and odors.
Keywords: nanowhiskers, tin dioxide, physical vapor deposition, gas sensor, gas sensitivity.
Khubolov B.M.
Electrochemical synthesis of tungsten oxide bronze powders — page 738
Abstract: Chemical analysis established that during electrochemical reduction in M2WO4 – WO3 (M – Li, Na, K, Cs, Tl) melts, tungsten oxide bronzes of various compositions and structures are formed. The dependence of the change in the equilibrium potentials of cathode products on the temperature and composition of the melt has been studied. It was found that with an increase in the content of alkali metal in tungsten melts, the number of crystal nuclei decreases. A decrease in the melt temperature and an increase in the cathode current density also lead to a decrease in the grain size of the cathode deposits, which makes it possible to obtain powders of tungsten oxide bronzes of controlled dispersion.
Keywords: oxide tungsten bronze, powders electrochemical synthesis, electrolytic reduction, molten salts.
Yurov V.M., Makhanov K.M., Portnov V.S.
Nanostructures in the thin layer of coal substance — page 746
Abstract: In the present work, the surface layer of a coal substance is considered, the structure and characteristics of which are different from the bulk structure. This layer has two levels: d(I) equal to 151,5 nm and d(II) ≈ 10 · d equal to 1515 nm for anthracite. For pure metals d(I) is equal 1 – 6 nm, that is 2 orders of magnitude lesser than the surface layer of the coal substance. The thickness of this layer is of the order of 135 nm for the higher C96 fullerenes. All these features of a coal substance, which has a carbon base and is a polymer with a supramolecular structure, lead to the fact that it is the surface layer that determines the physical processes in it associated with the flow of gases and liquids, as well as with the phenomena of the explosion hazard.
Keywords: surface layer, nanostructure, surface energy, atomic volume, size effect, coal substance.
5. NANOCHEMISTRY — page 758
Alekseenko N.A., Kovalenko M.N., Markova L.V., Zajogin A.P.
Processes of formation of nanodisperse Al2O3 powders with carbon in a dc electric arc — page 758
Abstract: The nanodisperse Al2O3 powders formation with carbon in a DC electric arc under the influence of an arc discharge between an D16T aluminum alloy electrode and a carbon electrode in the air atmosphere are studied. The effect of the arc current on the plasma-arc synthesis of an aluminum-carbon material, a precursor for production of hollow Al2O3 nanoparticles, was studied. It is found that with an increase in the arc current from 4 to 14 A, the amount of product increases by almost an order of magnitude, despite competing dissociation processes with an increase in temperature from 5000 to 5500 К.
Keywords: Al2O3 , AlO suboxides, DC electric arc, arc temperature, temperature of the area of formation of aluminum suboxides.
Alemasova N.V., Sukhova S.R., Kravchenko V.V., Zozulya M.A., Prokofieva L.A., Burkhovetskiy V.V., Savoskin M.V.
Sonication impact on the structure of graphite oxide reduced by thiourea — page 765
Abstract: The sonication impact on the process of the Hummers graphite oxide reduction by thiourea was investigated. It was found that treatment of the graphite oxide with thiourea leads to the partial removing of oxygen-containing and formation of sulfur-containing functional groups on the graphite oxide surface. The low-power ultrasound promotes an increase in the graphite oxide surface functionalization by sulfur. The morphology of the partially reduced and functionalized graphite oxide particles was studied by using the scanning and transmission electron microscopy. It was shown that ultrasound promotes the formation of a hydrogel with a highly developed surface.
Keywords: graphite oxide, reduction, functionalization, thiourea, sonication, structure, scanning electron microscopy, transmission electron microscopy.
Bakhvalova E.S., Nikoshvili L.Zh., Bykov A.V., Sidorov A.I., Kiwi-Minsker L.L.
Influence of the aromatic polymeric matrix type on stability of nanosized palladium catalysts in Suzuki reaction — page 775
Abstract: This work is devoted to the study of the influence of the type of polymeric matrix of hyper-crosslinked polystyrene on activity and stability of palladium catalysts of Suzuki cross-coupling. The use of the hyper-crosslinked polystyrene functionalized with tertiary amino groups was shown to be promising in terms of ensuring of the catalyst stability during recycles, but in order to achieve 100% conversion of aryl halide (4-bromanisole) the use of strong excess of phenylboronic acid and of a base is required. The catalyst based on non-functionalized hyper-crosslinked polystyrene had higher activity and allowed achieving complete conversion of 4-bromanisole during the reaction under mild conditions (70°C, ethanol and water mixture is in the ratio of 5:1 as a solvent) while using 1,5-fold excess of phenylboronic acid. However, strong adsorption of the cross-coupling product in a hydrophobic polymeric matrix was found to be a disadvantage of such a system.
Keywords: Suzuki cross-coupling, palladium, catalyst, nanoparticles, hyper-crosslinked polystyrene.
Bibanaeva S.A., Pasechnik L.A., Skachkov V.M., Surikov V.T., Yatsenko S.P.
Effect of metal additives in hydrochemical processing of diaspore-bemite bauxite on physicochemical properties of reduced muds — page 784
Abstract: The work is devoted to study of the high-temperature hydrochemical decomposition of mineral complexes of diaspore-bemite bauxites by the Bayer method with the extraction of macro-components-aluminum and iron in the presence of metal reducing agents. X-ray phase studies were performed to determine the composition and structure of new compounds in magnetized spent red mud. Based on the results of physical and chemical studies of leaching products, optimal parameters for reducing leaching of bauxite are recommended, aimed at extracting aluminum and synthesizing magnetite. The regularities of the influence of the type of metal reducing agent on the morphology, phase composition, and particle size in the red mud are revealed.
Keywords: bauxite, leaching, Bayer process, iron reduction, red mud, recycling, hematite, magnetite, dispersivity.
Gyrdasova O.I., Pasechnik L.A., Krasil’nikov V.N., Surikov V.T., Kuznetsov M.V.
Sorption and photocatalytic activity of Zn1-xCuxO (x = 0,05 and 0,15) to As(III) in an alkaline medium — page 792
Abstract: 1D solid solutions Zn1-xCuxO and composites Zn1-xCuxO / CuO with spherical morphology of aggregates from formate glycolate complexes Zn1-xCux (HCOO)(OCH2CH2O)1/2 (0 ≤ x ≤ 0,15) were obtained. All materials have been tested in the reaction of As(III) photooxidation upon exposure to ultraviolet and visible radiation. It was found that copper is an effective doping impurity in the composition of the solid solution Zn1-xCuxO (0 ≤ x ≤ 0,1). Its presence in the shell of the Zn1-xCuxO / CuO composite negatively affects the photoactivity of the material up to suppression of photocatalysis in the visible light range. The sorption efficiency of materials for arsenic is also shown, regardless of the composition and morphology of the material. According to x-ray photoelectron spectroscopy data, the surface of the samples after sorption contains arsenic mainly in the form of As(III).
Keywords: zinc oxide, nanoheterostructures, synthesis, precursors, morphology, microstructure, defective structure, dynamics of electronic excitations, photocatalysts.
Ivanov Yu.F., Petrikova E.A., Lykov S.V., Denisova Ju.A., Teresov A.D., Tolkachev O.S.
Structure and properties of the surface layer high chrome austenitic steel, submitted to ion-plasma nitrogen — page 805
Abstract: Ion nitriding is one of the most common methods of surface hardening of parts and tools. The purpose of this work is to identify and analyze the laws governing the transformation of the structure and properties of the surface layer of high-chromium stainless steel subjected to low-temperature nitriding in a low-pressure gas discharge plasma. It was found that the saturation with nitrogen (793 K, 3 hours) of austenitic high-chromium steel 20X23H18 in a low-pressure gas discharge plasma is accompanied by the formation of a plate type structure with alternating plates of austenite and iron nitride in a layer (55 – 60) μm thick (transverse plate sizes do not exceed 10 nm), the microhardness and wear resistance of which exceed the microhardness of the initial state by 6,5 times, wear resistance – more than 400 times.
Keywords: low pressure gas discharge plasma, austenitic steel, phase composition, defective substructure, microhardness, wear resistance.
Kovtun A.I.
Adsorption and dilational rheological properties of chitosan lactate at the liquid-gas interface — page 816
Abstract: The adsorption and dilatational rheological characteristics (the elasticity and viscosity modulus) of chitosan lactate at the liquid-gas interface are investigated by the oscillating drop shape method. The dependences of the dynamic and equilibrium surface tension on the concentration of chitosan lactate in solution have been determined. It was found that the dependences obtained are similar to those for surface-active high-molecular weight compounds. The dependences of the surface elasticity and viscosity of chitosan lactate on the oscillation frequency and concentration have been studied. It has been shown that chitosan lactate is capable of forming elastic adsorption layers with the values of the viscoelastic modulus comparable to that of protein biopolymers.
Keywords: chitosan, surface tension, viscoelastic modulus, elasticity modulus, viscosity modulus, liquid-gas interface.
Korabel M.D., Sinev I.V., Shikunov D.A., Klychkov N.A., Timoshenko D.A., Simakov V.V.
Principles of creating a virtual multi-sensor system for recognition gas mixtures — page 827
Abstract: The concentration dependence of the gas sensitivity of a gas sensor based on a nanostructured tin dioxide film was studied under various operating conditions in a wide range of concentrations of gases of various nature (ammonia, acetone, propanol, and ethanol). It has been experimentally shown that the concentration dependence of the gas sensitivity is power-law, the exponent n is different for different gas samples, and the value of the power-law exponent n depends on the operating mode of the sensor and the chemical nature of the sample being analyzed. The studied phenomenon makes it possible to recognize gas samples containing vapors of different chemical substances. The probability of classification of gas samples of ammonia, acetone, propanol and ethanol by the method of nearest neighbors was more than 95%.
Keywords: tin dioxide, nanostructured films, adsorption on an inhomogeneous surface, recognition of organic vapors.
Kuznetsov Yu.A., Lapushkin M.N.
Electron-stimulated desorption of potassium atoms adsorbed on the surface of gold — page 836
Abstract: An ultrathin intermetallic layer KxAuy was created at room temperature by depositing potassium atoms on adsorbed gold layer on the tungsten surface. The processes of electron-stimulated desorption of K atoms from the KxAuy surface are investigated. Quasi-resonance peaks are found in the dependence of the ESD yield on the excitation energy at 64 and 82 eV, which correspond to the excitation of the core levels Au 5p3/2 and Au 5p1/2. The obtained results indicate the formation KxAuy of different stoichiometry: from KAu8 to KAu. It is shown that the intermetallic compound KxAuy created at room temperature is a semiconductor, as it was previously obtained at 1000 K. A model of electron-stimulated desorption of K atoms in the K / KxAuy / Au / W system is proposed
Keywords: electron-stimulated desorption, adsorption, alkali metals, gold, intermetallic compounds.
Malkanduev Yu.A., Begieva M.B., Kokoevа A.A., Mikitaev A.K., Dzhalilov A.T.
Chemical transformations of copolymers of acrylic acid α–haloid with N–vinylpyrrolidone — page 845
Abstract: The paper presents results on copolymerization of α-halogens acrylic acid and N-vinylpyrrolidone in the presence of aminating agents at low temperatures in an organic environment. The IR spectra of the obtained copolymers confirm the amination reaction. The dependences of the reduced viscosity of synthesized polymers aqueous solutions were studied and a «polyelectrolyte swelling» was observed. The synthesized aminated polymers form internal complex compounds with divalent metal halides at room temperature. This paper describes the first attempts to obtain new nanocomposite materials based on synthesized copolymers and modified montmorillonite. Analysis of the literature data shows that the features of obtaining nanocomposites based on Na+-montmorillonite and water-soluble copolymers have not been studied before.
Keywords: water soluble polyelectrolytes, copolymerization, acrylic acid, N-vinylpyrrolidone, amination, nanocomposites.
Menshikov S.Yu., Belozerova K.A., Ostroushko A.A.
Influence of the nanocluster {Mo72Fe30} polyoxometalate on oxidation of iodide–ions by persulfate — page 853
Abstract: Catalytic properties of the nanocluster iron-molybdenum polyoxometalate {Mo72Fe30} in solutions during the oxidation of iodide ions by persulfate have been studied. Automated installation based on spectrophotometric method of analysis controlled by computer was used. Comparison of literary data and kinetic datа on the oxidation of iodide with persulfate showed that keplerate {Mo72Fe30} is a heterogeneous catalyst. These data allowed to assume a non-radical mechanism for persulfate decomposition on the surface of cluster molecules at the first stage of the potassium iodide oxidation reaction. The value of the effective activation energy of the process indicates the catalytic effect of {Mo72Fe30} at the intermediate stage of the decomposition of the hydrogen peroxide.
Keywords: nanocluster iron-molybdenum polyoxometalate, keplerate, catalytic properties, oxidation of iodide ions, potassium persulfate, hydrogen peroxide..
Musskaya O.N., Krut’ko V.K., Kulak A.I.
Synthesis of magnesium phosphates in a polymeric matrix — page 860
Abstract: The dependence of the phase composition of nanoscale magnesium phosphates (MgNH4PO4 · 6H2O, Mg(H2PO4)2, MgHPO4 · 3H2O, Mg3(PO4)2 · 22H2O) with 13 – 54 nm crystallite size on the conditions of precipitation from aqueous solutions in the presence of the polyvinyl alcohol and its mixture with polyvinylpyrrolidone was studied. In the polymer matrix an additional impurity phase MgOHCl is formed. The presence of medium and disubstituted magnesium phosphates in polymer films of polyvinyl alcohol and polyvinyl alcohol / polyvinylpyrrolidone inhibit their thermal destruction.
Keywords: smagnesium phosphates, struvite, newberite, polyvinyl alcohol, polyvinylpyrrolidone, composite polymer film.
Mustafaev G.A., Mustafaev A.G., Panchenko V.A., Cherkesova N.V.
Method of ionic mixing for silicide layer formation — page 868
Abstract: Ion implantation with recoil ions or ion mixing based on the introduction of the required impurity from the surface layers during the transfer of the kinetic energy of the primary beam to them have great prospects for obtaining structures and compounds with desired properties. In the process of ranging of very large scale integrated circuits, the parasitic resistance of interconnections and the non-ohmic nature of contacts are the limiting factors. Refractory metal silicides are promising materials for use in metallization systems. In this work a study was carried out on the introduction of phosphorus ions into molybdenum-silicon systems. The results obtained demonstrate the possibility of the molybdenum silicide formation at a low temperature using implantation of ions that cause ionic mixing. The developed technology makes it possible to achieve a homogeneous interface between the silicide and silicon with the necessary electrophysical characteristics of metalization and ohmic contacts. Due to the deepening of the interface into the bulk of the semiconductor, the effect of the silicon surface state on parameters of ohmic contacts decreases. As a result their necessary stability and reproducibility are ensured.
Keywords: ion implantation, ohmic contact, metallization, silicide, sputter deposition, heat treatment, integrated circuit.
Simonov Ya.I., Skvortsova Z.N., Traskin V.Yu.
Calcite powder deformation in the presence of aqueous solutions of various composition — page 875
Abstract: The rates of calcite powder compaction under uniaxial stress in CaCO3 saturated aqueous solutions containing magnesium cations or humate anions have been compared with computed rate estimations. The interplay of calcite solubility, dissolution kinetics, and mass transfer rate of solid matter through the liquid bulk controls the overall process kinetics. A not significant difference between the experimental and calculated datasets (within 20%) confirms the adequacy of the model proposed. The calcite creep rate in magnesium-containing media is limited by the material dissolution stage as a result of the surface dolomitization. The creep hindering by humate anions is likely to be due to the partial surface coverage with adsorbed matter.
Keywords: pressure solution. kinetic and diffusive regime of deformation, solubility, dissolution rate. liquid interlayers, diffusion coefficient.
Tonkushina M.O., Gagarin I.D., Russkikh O.V., Belozerova K.A., Ostroushko A.A.
Destruction of polyoxometalate {Mo72Fe30} as a transport agent in blood simulating media, its stabilization by albumin — page 885
Abstract: The creation and use of the targeted drug delivery systems based on nanocluster polyoxometalate {Mo72Fe30} implies its destruction in the body, accompanied by the gradual release of the drug. The rate constants of the destruction of pure {Mo72Fe30} and its associate with serum albumin in solutions simulating the blood media (phosphate buffer with pH 7,4 and blood serum of cattle) were determined. The stabilization of polyoxometalate by albumin in model solutions was shown. The ratio of components in the associate {Mo72Fe30}–albumin was determined, it was 1,6 polyoxometalate ions per albumin molecule.
Keywords: polyoxometalate, nanocluster, {Mo72Fe30} , protein corona, targeted delivery, the rate of destruction, the rate constant of the reaction.
6. PERSONALIA — page 893
Malyshkina O.V.
In memory of Rostislav Mikhailovich Grechishkin (1941–2020) — page 893
Abstract: This short communication is dedicated to memory of Rostislav Mikhailovich Grechishkin, an outstanding Soviet and Russian physicist, a specialist in the field of magnetic phenomena, Dr. of physical and mathematical Sciences, Professor of the Applied Physics Department at the Faculty of Physics and Technology of Tver State University, head of a scientific school in magnetoelectronics.
Keywords: magnetism, magnetooptics, ferromagnetic shape memory alloys, domain structure, nanostructured materials, methods and means of magnetic measurements.
Alemasova N.V., Savoskin M.V., Vdovichenko A.N., Prokofieva L.A.
Limitations in titrimetric determination of acid groups in graphite oxide – page 6
Abstract: Тhe Boehm titrimetric method gives distorted results when determining total quantity of acid groups total quantity in Hammers’ graphite oxide. It was established that the additional acidity of the aqueous phase of the Hammers graphite oxide suspension is due to intercalated sulfuric acid. The adding alkali during the acid-base titration is accompanied by the reaction of Hammers’ graphite oxide decarboxylation. Such an effect was not observed for an aqueous suspension of Brodie’s graphite oxide.
Keywords: graphite oxide, acid functional groups, cyclic acid-base titration.
Aref`eva L.P., Shebzukhova I.G., Sakhno T.A., Shakova L.S.
Application of atomic-force microscopy for investigation of anisotropy of interphacial energy on the boundary of the metal-oriented substrate – page 16
Abstract: A method we developed for determining anisotropy of the interfacial energy in a solid system was used to investigate nickel nanocrystals on an oriented silicon substrate. Nickel particles were obtained by the vapor-liquid-solid mechanism, i.e. by vacuum deposition on a substrate. The surface of the sample was visualized by the atomic force microscopy in the tapping mode. A analysis of AFM images made it possible to establish the geometric characteristics of nickel crystals and to investigate the relief. Based on the data obtained, the model shape and position of the Wulf point of the equilibrium crystals on the substrate are determined. The dependences of the characteristic value A/V2/3 on the effective contact angle in two directions are constructed and it is shown that in this system the interfacial energy of the crystal-substrate interface is highly anisotropic.
Keywords: interface energy, wetting, nanocrystals, nickel, atomic-force microscopic.
Ashkhotov O.G., Ashkhotova I.B., Aleroev M.A., Krimshokalova D.A.
Electron-stimulated oxygen adsorption on the surface of metals and semiconductors – page 26
Abstract: The phenomenon of electron-stimulated adsorption occurs in almost all devices where electron emission is used. Electron-stimulated adsorption can have a significant effect on the state of the adsorbed layer. This review presents typical results obtained in the study of electronically stimulated processes of the oxygen adsorption from a gas phase and the main patterns of changes in the surface structure caused by electron-stimulated adsorption.
Keywords: spectroscopy, surface, electrons, radiation, dissociation, migration, adsorption, desorption, experiments, exposure.
Bagrysheva I.S., Bolshakova N.N., Ivanova A.I., Rumyancev V.S., Semenova E.M.
Deuterated triglicine sulfate crystals switching processes – page 40
Abstract: The results of the study of dynamic processes of repolarization of crystals of pure and deuterated triglycine sulfate are presented. It is established that deuteration and an increase in the concentration of the alanine impurity in deuterated crystals lead to a decrease in the relative and effective dielectric constants, switchable polarization and an increase in the coercive field and the displacement field. Deuteration and substitution of a part of glycine molecules into alanine allows obtaining a stable unipolar state in crystals.
Keywords: processes of switching, domain structure, triglicinsulfate, deuteration, scanning electron microscopy.
Bazzal K., Voropay Е.S., Zajogin А.P., Patapovich М.P.
Spectral studies of the defocusing effect on the AlO and AlN formation processes when D16T aluminum alloy is subjected to double laser pulses in air – page 48
Abstract: The effect exerted by defocusing of double laser pulses on purposeful formation of the component and charge composition of the laser plasma has been studied using the laser spark spectrometry (LSS-1 laser). It has been shown that there is a possibility to increase the portion of differently charged aluminum ions as well as of AlO and AlN nanoclusters in the laser plasma when a target of D16Т aluminum alloy is subjected to a series of defocused double pulses.
Keywords: AlO, AlN, pulsed laser deposition, laser plasma, laser spark spectrometry, multiply charged ions, double laser pulses.
Bazzal K., Voropay Е.S., Zajogin А.P., Patapovich М.P.
Investigation of the channel-form effect on the formation processes of AlN and AlO nanoclusters in plasma when aluminum target is subjected to series of double laser pulses in air – page 57
Abstract: The microchannel-form effect on the formation of AlO and AlN in the laser plasma has been studied when the surface of a target of D16Т aluminum alloy was subjected to series of sequential focused double laser pulses in air. The possibility to increase the quantities of AlO and AlN as well as of nitrogen, oxygen, and aluminum ions with different charges in the laser plasma has been demonstrated depending on the microchannel form.
Keywords: AlO, AlN, pulsed laser deposition, laser plasma, laser spark spectrometry, multiply charged ions, double laser pulses, form of microchannel.
Bakhvalova E.S., Nikoshvili L.Zh., Matveeva V.G., Kiwi-Minsker L.
Palladium nanoparticles stabilized in aromatic polymeric environment – highly active ligandless catalysts of Suzuki cross-coupling – page 65
Abstract: This work is devoted to the study of influence of the type of polymeric matrix of hyper-crosslinked polystyrene on the formation of catalytically active palladium nanoparticles using palladium acetate as a precursor. It was shown that the use of nonfunctionalized hyper-crosslinked polystyrene as a support allows formation of palladium nanoparticles of larger diameter (4-10 nm) than in the case of the polymer functionalized with amino groups. However, this catalyst exhibits higher activity in the Suzuki cross-coupling reaction between 4-bromoanisole and phenylboronic acid. For the most active catalyst, the influence of the reaction temperature, solvent composition and the nature of base were studied. Moreover, the study of the influence of the aryl halide nature revealed that the use of competing substrates allows achieving 100% conversion for 4 minutes of 4-iodoanisole in the presence of 4-bromoanisole.
Keywords: Suzuki cross-coupling, palladium, catalyst, nanoparticles, hyper-crosslinked polystyrene.
Belyakova R.M., Piven V.A., Sidorov N.I., Polukhin V.A.
Influence of Ti – H hydrides on interatomic interactions and on characteristics of Ti alloying membrane alloys based on V – Ni – page 74
Abstract: Under the conditions of the fast crystallization of melts, the effect of hydrogen on mechanisms of structural transformations in V85Ni15 and V85-xTixNi15 alloys was experimentally studied. Structuring of phase compositions, diffusion, and hydrogen permeability were simulated. The regularities of improving the structural characteristics of alloys as a result of alloying with titanium, as well as the effect of hydrogen dynamics on the stability of the formed phases are revealed.
Keywords: hydrogen, BCC phase, diffusion, permeability, simulation, multiparticle potentials, titanium alloys, microstructure, hybridization of polymorphic-phase transitions, membrane technologies, hydrides.
Bernatskii D.P., Pavlov V.G.
Field electron emission from nanostrutured surface of carbonized iridium – page 86
Abstract: The characteristics of the field electron emission of the iridium tip with different carbon formations on its surface are investigated. It was found that in some cases, compared to metal emitters the carbon-coated emitter exhibits significantly greater emission stability and resistance to residual gases when operating in insufficiently good vacuum conditions.
Keywords: electron emission, carbon, iridium, vacuum, surface.
Bernatskii D.P., Pavlov V.G.
Cesium field desorption for visualization of graphite nanostructures on the surface of a rhenium field emitter – page 91
Abstract: Desorption of cesium atoms in an electric field from the carbonized rhenium field emitter was investigated by the field desorption microscopy. The effect of the concentration of cesium atoms on the voltage and on the distribution of emission centers on the surface of the emitter is studied. It is shown that rhenium carburization can lead to a surface modification with the formation of carbon nanostructures.
Keywords: field desorption microscopy, electric field, field emitter, alkali metals, graphite nanostructures.
Bobreva L.A., Masloboeva S.M., Sidorov N.V., Palatnikov M.N.
The effect of Mg and Fe dopants on concentration of complex defects associated with OH – groups in the lithium niobate crystal – page 97
Abstract: In the spectra of infrared absorption in the region of stretching vibrations of OH– -groups the effect is investigated of dopants Mg, Mg + Fe on the concentration of complex defects of MgNb – OH – MgLi, FeNb – OH – MgLi in lithium niobate crystals grown from the charge, synthesized with the use of homogeneously doped Nb2O5 precursor.
Keywords: homogeneous doping, charge, single crystal, lithium niobate, stretching vibrations of groups, complex defects.
Burtsev A.A., Butkovskii O.Ya.
Analysis of crystal structures on stainless steel surface – page 107
Abstract: In this paper experiments of crystallization from melt with an analysis of the morphology of formed crystal structures are presented, examples of the forming of complex dendritic formations are shown. The chemical composition of various types of crystals was established by energy dispersive X-ray spectroscopy. The relationships between the features of the forming morphology and its composition are analyzed.
Keywords: laser heating, metal surface modification, crystallization, fractal, dendritic crystals, energy dispersive spectroscopy.
Dyshekova A.Kh., Karmokov A.M., Bzhikhatlov K.Ch.
Interfacial characteristics of potassium and sodium chlorides doped with silver, tin and copper on the boundary with liquid lead – page 115
Abstract: Influence of small additives of copper, silver and tin on the wetting angle and the work of adhesion of monocrystals of potassium and sodium chlorides is considered. The nature of interfacial interactions at the lead – single sodium/potassium chloride boundaries has been revealed with respect of the above additives.
Keywords: angle of wetting, work of adhesion, sodium chloride, potassium chloride, monocrystal.
Eguzhokova R.M., Ivanova A.I., Semenova E.M.
Domain structure and magnetic transport properties on thin ferrite-garnet films – page 123
Abstract: This article provides an overview of the results of an experiment on the application of the magnetotransport properties of ferrite – garnet films in microfluidic devices, as well as on the determination of the composition of immunomagnetic microspheres. The article provides practical recommendations on the use of ferrite garnet films for the controlled transport of magnetic microspheres.
Keywords: ferrite-garnet films, magnetic microspheres, magnetic manipulation.
Efremov V.V., Palatnikov M.N., Shcherbina O.B.
Comparative study of electrophysical characteristics of ceramic and monocrystalline lithium tantalate – page 129
Abstract: The microstructure of ceramic lithium tantalite LiTaO3, obtained on the basis of finely dispersed microcrystalline monophasic powder, was studied by the probe microscopy. A comparative study of the dispersion of the complex impedance Z*(ω) of LiTaO3 and a crystalline sample of a non-polar X-orientation slice, grown by the Czochralski method, was carried out. Using measured Z and φ values, the real and imaginary components of the complex dielectric constant and impedance (admittance) are determined.
Keywords: lithium tantalate, ceramics, microstructure, impedance spectroscopy, dielectric permittivity, electrical conductivity.
Ivanov D.V., Antonov A.S., Sdobnyakov N.Yu., Semenova E.M., Scopich V.L., Romanovskaia E.V., Afanasiev M.S.
Fractal properties of nanosized films of nickel and chromium – page 138
Abstract: The morphology of the relief of nanoscale films of nickel and chromium on the surface of the mica was studied using a scanning probe microscope. The characteristic features of nanorelief of the surface of the studied films, including fractal properties, are described. The obtained fractal dimension data are compared with the available experimental data, as well as data obtained using scanning tunneling microscopy. Recommendations on the development of the technology of «growing» structures with a given surface morphology are proposed.
Keywords: scanning probe microscopy, nanorelief, fractal dimension, nanoscale films of nickel and chromium.
Izmailov V.V., Novoselova M.V.
On the ratio of diffusive and ballistic components of electrical contact resistance on micro- and nanoscale levels – page 153
Abstract: The ratio of diffusive and ballistic components has been analyzed of a contact electrical resistance as well as a role of the micro- and nanoroughness of contact surfaces in a generation of an electrical contact resistance and its components. In a contact of nanoroughness asperities a ballistic component of a resistance dominates, whereas in a contact of microroughness asperities a diffusive one.
Keywords: electrical contact, contact resistance, diffusive resistance, ballistic resistance, microroughness, nanoroughness.
Kiseleva M.A., Sokovnin S.Yu., Balezin M.E.
Production and characterization of Al2O3 + Ag composite nanopowders – page 161
Abstract: Nanoparticles of aluminum oxide partially coated with silver were obtained by the radiation-chemical method in size 50 and 80 nm, and the coating area was 2-3% and 16-40%, respectively. The stability of the suspension before irradiation using different stabilizers was studied. The reason for the color change of suspensions after sonication is determined. The antibacterial activity of the composite nanopowder was investigated on wine yeast.
Keywords: nanopowders, nanoparticles, nanosecond electron beam, silver-coated alumina, antibacterial properties.
Knatko M.V., Lapushkin M.N.
Study of methenamine adsorption on intermetallic NaAu2 by the surface ionization – page 169
Abstract: Based on a study of the surface ionization of methamine on the surface of the NaAu2 alloy, the orientation of adsorbed molecules is analyzed. It was determined that ionization and exchange reactions between adsorbed molecules occur at specific centers of the alloy, to which a record high work function of the surface yield of more than 7,6 eV can be attributed.
Keywords: adsorption, surface, work function, methenamine, surface ionization, mass spectrometry.
Kokoeva A.A., Begieva M.B., Malkanduev Yu.A., Dokshukina M.A.
Conductometric method for determining the conductivity of polyelectrolyte solutions – page 177
Abstract: A new polymer-based aminoethanoic acid was obtained by the reaction of the radical polymerization. The molar and specific conductivity values of aqueous solutions of the initial amino acid, monomer and polymer were measured by the conductometric method. The results demonstrate the most pronounced electro-conductive properties of the polymer – poly – N, N – diallylamine acid.
Keywords: polyelectrolytes, physical and chemical properties, electrical conductivity, molar conductivity, specific conductivity, electrical conductivity.
Kuznetsov Yu.A., Lapushkin M.N.
Electron-stimulated desorption of lithium atoms from oxygen monolayer covered tungsten – page 184
Abstract: The electron-stimulated desorption of neutral lithium atoms from the oxygen monolayer covered the tungsten surface have been studied. The model of the atom electron-stimulated desorption processes on the tungsten surface with the adsorbed oxygen monolayer have been suggested. Both common and different features of the electron-stimulated desorption processes have been foundfor high-energy and low-energy peaks in the kinetic energy distributions of the desorbed atoms.
Keywords: electron-stimulated desorption, adsorption, alkali metals.
Malashenko V.V., Malashenko T.I.
Features of dislocation dynamics in near-surface nanoregion of crystal – page 192
Abstract: The glide of dislocations in a near-surface nanolayer of crystal containing point defects is theoretically analyzed. An analytical expression for the dynamic drag force of dislocations by point defects is obtained. It has been shown that the crystal surface has a significant effect on the dislocation dynamics in the near-surface region.
Keywords: dislocations, point defects, surface, nanomaterials.
Malyshkina O.V., Tesnikova E.S., Malysheva N.E., Ivanova A.I.
Structural features of sodium – lithium niobat ceramics – page 198
Abstract: The authors synthesized samples and studied the structure of piezoelectric ceramics based on sodium and lithium niobates Li1-xNaxNbO3. A significant dependence of the grain formation during sintering of the samples on the ratio Li / Na is revealed. Based on the analysis of the structure and measurement of the temperature dependence of the dielectric constant, the optimal compositions for practical application are proposed Li0,1Na0,9NbO3 and Li0,4Na0,6NbO3.
Keywords: piezoelectric ceramics, lead-free materials, grain structure.
Milekhin Yu.M., Koptelov A.A., Koptelov I.A., Rogozina A.A.
Thermal decomposition kinetics of an energy composite material on the basis of inert binding – page 206
Abstract: The results are presented of the study of thermal decomposition kinetics of the K – 2 model mixed energetic material, the main components of which are ammonium perchlorate, octogen, aluminum and an inert binder, polybutadiene, plasticized with transformer oil. The activation energy E was determined by isoconversion methods and the Kissinger method according to thermal analysis at heating rates b < 5 K / min. In an open system, the evaporation of plasticizer (Emin = 65 kJ / mol), thermal decomposition of octogen (Emax = 192 kJ/mol) and ammonium perchlorate are successively realized in the samples. When limiting the free exit of gaseous reaction products, the peaks of the maximum heat release rate in octogen shift to the region of higher temperatures, the thermal decomposition of K – 2 is completed earlier than in the open system. An explanation of the mechanism of this phenomenon is proposed.
Keywords: energetic material, octogen, ammonium perchlorate, thermal decomposition, activation energy.
Ostroushko A.A., Russkikh O.V., Gagarin I.D., Filonova E.A.
Study of the charge generation in the synthesis of nanosized complex oxides in the combustion reactions of organo-inorganic precursors – page 215
Abstract: The presence of the generation of electric charges in precursors during the synthesis of nanosized complex oxides in the combustion reactions of compositions including metal nitrates, as well as glycine and glycerin as organic components, is shown. To measure the resulting potential difference, an automated system based on the IPEP-1 electrostatic field parameter meter and a signal amplification system were used.
Keywords: Nanosized complex-oxide materials, combustion synthesis, organic-inorganic compositions, charge generation, measurements.
Sidorov N.V., Teplyakova N.A., Titov R.A., Palatnikov M.N.
Influence of boron on structural features and photorefractive properties of LiNbO3 single crystals – page 223
Abstract: An analysis of studies of single crystals of LiNbO3 stoich, LiNbO3 cong and LiNbO3 : B (0,83 mol.% B2O3 in the charge) was performed. It was established that boron present in the melt is unable to incorporate into the crystal structure of LiNbO3. Boron brings closer in magnitude to each other the effective distribution coefficients of lithium and niobium linking excess niobium in the process of complexation in a melt of a congruent composition. In this case, LiNbO3 : B crystals approach to the stoichiometric crystals in ordering the structural units.
Keywords: single crystal, lithium niobate, photoelectric field, boron, doping, melt structuring.
Starodub O.R., Voskresenskij V.M., Sidorov N.V., Palatnikov M.N.
Analysis of cluster formation in modeled lithium niobate crystals – page 232
Abstract: In the framework of the semiclassical atomistic model, clusterization processes in a lithium niobate crystal LiNbO3 were investigated. Computer modeling of the energy-equilibrium cluster of a lithium niobate crystal LiNbO3 based on oxygen octahedrons has shown that random throwing of ions to the center of the octahedron is more energy-efficient, and a cluster with a congruent Li / Nb ratio is optimal in energy for any casting method and model cluster size .
Keywords: lithium niobate, modeling, clusters, vacancy models, sublattice defects, single crystals, ferroelectrics.
Teplyakova N.A., Sidorov N.V., Palatnikov M N.
Photorefractive properties and optical uniformity of crystals LiNbO3 (6,0 wt. % K2O) – page 241
Abstract: Comparative researches were carried out for lithium niobate crystals with congruent and stoichiometric composition with a different genesis. It was shown that it is possible to obtain LiNbO3 crystals close in composition to stoichiometric, grown from a congruent melt with the addition of a 6.0 wt.% K2O flux. Such crystals are far superior to optical uniformity and photoelectric parameters of congruent crystals.
Keywords: single crystal, lithium niobate, photoelectric field, band gap, IR absorption spectrum, stretching vibrations of OH-groups.
Khil’ko S.L., Rogatko M.I., Makarova R.A., Semenova R.G.
Using the dilatational rheology method for analysis of nanosized systems – page 249
Abstract. The regularities of the formation of interfacial layers of nanosized natural polyelectrolytes based on humic substances and their complexes with cationic surfactants are investigated. It is shown that application of the dilatation rheology method makes it possible to explain the behavior of such systems at the liquid-gas interface.
Keywords: dilatation rheology, interphase layers, nanosized systems, natural polyelectrolytes, salts of humic substances, surfactant-polyelectrolyte complexes.
Khubolov B.M., Podlinov V.P.
Features of the electrochromium effect in complex transition metal oxides – page 259
Abstract: Some features of electrochromically sensitive single crystals and thin films of the complex transition metal oxides are reviewed. Based on the results of studies that allow us to draw conclusions about specific models of the physical process underlying the electrochromic effect, the most urgent questions of further studies of complex transition metal oxides are formulated to obtain applied results that can form the basis of highly efficient technology of electrochromic devices. The efficiency of complex transition metal oxides as a more promising electrochromic material is substantiated.
Keywords: electrochromic effect, complex transition metal oxides, oxide tungsten bronze, monocrystals, thin films.
Shishulin A.V., Shishulina A.V.
Several peculiarities of high-temperature phase equilibria in nanoparticles of the Six – Ge1-x system – page 268
Abstract: Phase equilibria in Six – Ge1-x nanoparticles of various compositions within the two-phase region between the liquidus and solidus temperatures have been simulated by using methods of the equilibrium chemical thermodynamics. It has been shown that the equilibrium compositions of liquid and solid phases dramatically depend on the initial composition of a nanoparticle and the character of such dependences is different at different temperatures. Reducing the size of a nanoparticle is accompanied by narrowing the temperature interval of the two-phase region.
Keywords: nanostructuring, nanoparticles, germanium, silicon, melting, liquidus, solidus.
Shomakhov Z.V., Molokanov O.A., Karmokov A.M.
On special features of studying electric conductivity in special electron optics glasses – page 277
Abstract: The laws of the change in the electrophysical properties of the C87 – 2, C78 – 4, C78 – 5 glasses, used in electronic optics are studied. A comparative analysis of the effect of the transmitted electric current on the formation of a new phase and the time to achieve the phase equilibrium in glasses is carried out. It was established that annealing leads to an equilibrium state, stabilizes the structure, and also reduces the electrical conductivity of the glass.
Keywords: microchannel plate, lead-silicate glass, borate-barium glass, electrical conductivity, isothermal annealing, electromass transfer, phase equilibrium.
Belyaeva I.N., Kirichenko I.K., Ptashnyi O.D., Chekanova N.N., Chekanov N.A., Yarkho T.A.
The computer – assisted solution of the one – dimensional Schrödinger equation taking into account tunneling effects – page 283
Abstract: The general scheme of the method of integration of the second order ordinary differential equations with regular singular points is outlined. The algorithm of finding a general solution of the second order differential equation with regular singular points is given. The Schr dinger equation for anharmonic oscillator with the potential of the fourth, sixth and eighth degrees of non-linearity is considered, the values of its energy spectrum are found.
Keywords: ordinary differential equation, anharmonic oscillator, wave function, generalized power series.
Belyaeva I.N., Chekanov N.A., Kirichenko I.K., Chekanova N.N.
Accounting of tunneling effects when calculating the energy spectrum of the Schrödinger equation – page 291
Abstract: The general scheme of the method for integrating second-order differential equations in the form of power series is presented. The obtained results for the Schrödinger equation with potentials with two and three minima for quantum anharmonic oscillators are presented. The necessary accuracy of calculations is controlled by the number of terms in the power series and the number of digits in the mantissa of decimal numbers. The structure of the energy levels and wave functions are shown.
Keywords: ordinary differential equation, energy spectrum, wave function, generalized power series.
Blinov A.V., Gvozdenko A.A., Yasnaya M.A., Golik A.B., Blinova А.A., Shevchenko I.M., Kramarenko V.N.
Effect of synthesis parameters on dimensional characteristics of Fe3O4 nanoparticles: neural-network research – page 298
Abstract: Our research shows the possibility of using the neural-network processing of experimental data to study the influence of various factors on the process of synthesis of nanoscale Iron (II, III) oxide. A mathematical model was obtained which adequately describes the effect of temperature, stabilizer mass and precipitant quantity on the size of nanoparticles of Iron (II, III) oxide. The optimal synthesis conditions were determined, which provide a high content of Fe3O4 particles with an average hydrodynamic radius less than 100 nm.
Keywords: double iron oxide nanoparticles, neural network modeling, multilayer perceptron, response surface, dynamic light scattering method.
Kiselev V.M., Golovanova O.A.
Application of the fractal theory for studying brushit crystallization process in the presence of additives – page 307
Abstract: The paper considers the possibility of using the fractal analysis method for brushite-based samples, including modified with organic and inorganic additives. The dependencies between fractal parameters and properties of samples are determined. The results of the study can be used to develop the express methods used for analysis of synthetic biomaterials based on calcium phosphates.
Keywords: brushite, fractal analysis, precipitation, calcium phosphates, fractal dimension, biomaterials, drying drops.
Kramynin S.P.
Change in the baric dependences of the thermophysical properties of a niobium nanocrystal with a change in size – page 315
Abstract: From a general point of view, the equation of state and the change in thermophysical properties of Nb nanocrystals along 300 K and 3000 K isotherms with increasing pressure were calculated on the basis of the Mie – Lennard – Jones pair interatomic interaction potential and the nanocrystal RP model. The change in the baric dependences of thermophysical properties and the melting temperature of niobium nanocrystal with decreasing its size was studied.
Keywords: niobium, nanocrystal, size dependences, equation of state, melting point.
Musskaya O.N., Krut’ko V.K., Kulak A.I., Nasan A.A., Hvesenya S.S., Dobysh V.A., Tarasevich V.A., Budeiko N.L., Sycheva O.A.
Three-dimensional models based on polylactide and hydroxyapatite – page 326
Abstract: Three-dimensional models based on polylactide containing 1 and 5% hydroxyapatite were obtained by the method of fused deposition. In vitro testing showed that a surface modification of the polymer models with 4% hydroxyapatite gel or an aqueous suspension containing 4% polyvinyl alcohol and 4% hydroxyapatite can improve bioactive properties of such materials.
Keywords: 3D printing, fused deposition, polylactide, hydroxyapatite, polyvinyl alcohol.
Nagorny Y.E.
Numerical simulation of mechanical behavior of silicene in a general harmonic filed model – page 336
Abstract: The stiffness coefficients of two linear and two angular elements for the generic harmonic field model are derived from the stiffness coefficients of two linear elements for the central force field model. Recalculation is carried out through frequencies of three-node element assembled from these elements. Numerical modeling of uniform stretching of silicene samples was performed. Longitudinal and two transverse elastic modules are found to be dependent on linear dimensions.
Keywords: general harmonic field, silicene, stiffness coefficients, natural frequency, Young’s modulus, Poisson’s ratio.
Polukhin V.A., Belyakova R.M.
The specifics of the formation of Friauf cluster structures, 2D – packaging of the kagome and Laves phases during the hydrogenation of titanium alloys. Kinetics of hydrogen – page 345
Abstract: Using the results of computer modeling and experiment, an analysis has been made of the effect of hydrogen and its kinetics on the nature of the formation of cluster-block configurations in alloys – Laves phases based on Friauf polyhedra and kagome structures that determine the characteristics of new materials with the aim of advancing the ecological and energy-saving technologies for producing ultrapure hydrogen and then its accumulation in the concerning alloys.
Keywords: titanium alloys, hydrogenation, crystallization, modeling, Friauf polyhedra, diffusion, close-packed configurations, kagome nanostructures, cluster symmetry, Laves phases.
Rybina S.S., Tretyakov S.A.
Modeling process of distribution of light flow in the environment with diffusing centers – page 356
Abstract: A mathematical model is developed for calculating parameters of light fluxes propagating through a light-scattering and absorbing medium. Single crystals of paratellurite and germanium with known optical parameters and densities of various absorbing and scattering inhomogeneities were chosen as mediums.
Keywords: scattering, reflection, refraction, Bouguer-Lambert law, scattering indicatrix.
Talyzin I.V., Kartoshkin A.Yu., Vasilyev S.A., Samsonov M.V., Samsonov V.M.
On phase diagram of Au-Si nanoalloy: molecular dynamics and thermodynamic simulation – page 364
Abstract: Phase diagrams for Au-Si nanoparticles were constructed by using molecular dynamics and thermodynamic simulation, based on the CALPHAD methodology extended to nanoscale objects. It was established that the eutectic temperature of nanoparticles decreases by about 200 K compared to the bulk eutectic temperature, and the position of the eutectic point slightly shifts to a lower value of the molar fraction of Si.
Keywords: Au-Si nanoalloy, phase diagram, molecular dynamics, thermodynamic simulation, CALPHAD.
Chesnokova N.A., Gushchina A.S., Kuranova N.N.
Thermodynamics of complex formation of copper (II) with isonicotinamide and acid-basic equilibrium of ligand in water-organic solutions – page 374
Abstract: The stability constants of copper complexes with isonicotinamide and the ligand protonation constants in a range of compositions of a water-ethanol solvent of 0.0 – 0.7 molar fractions of ethanol at 298.2 K and an ionic strength of the medium 0.25 (NaClO4) were obtained by potentiometric methods.
Keywords: isonicotinamide, copper (II), potentiometry, ethanol, solvent, thermodynamics, aqueous-organic solutions.
Shishulin A.V., Shishulina A.V.
Equilibrium phase composition and mutual solubilities in fractal nanoparticles of the W – Cr heavy pseudo-alloy – page 380
Abstract: The influence of the nanomorphology on phase equilibria in core-shell nanoparticles of the stratifying W – Cr solid solutions has been simulated using methods of the equilibrium chemical thermodynamics. The nanoparticle shape has been determined by the value of the fractal dimension. The dependences of the mutual solubilities on the fractal dimension of nanoparticles have been calculated and some significant changes in the thermal stability of heterogeneous states in nanoparticles of different shapes have been revealed.
Keywords: decomposition of solid solutions, solubility, shape effect, core-shell, tungsten, chromium, fractal dimension.
Yurov V.M.
Thickness of the surface layer of atomic-smooth crystals – page 389
Abstract. A brief review of the physics of the surface layer of atomically smooth crystals is given. It already contains a fairly large number of practical applications in various fields of interdisciplinary areas. It has been shown that the thickness of the surface layer is determined by one fundamental parameter – the atomic volume of the crystal.
Keywords: surface layer, nanostructure, surface energy, atomic volume, size effect.
Baburkin P.O., Malyshev M.D., Ivanov V.A, Komarov P.V.
Can the crystallization of conjugated polymers be taken into account in simple mesoscopic models? – page 398
Abstract: The problem is considered of constructing coarse-grained models of matrices of conjugated polymers with regard to their crystallization. The performed simulation within the framework of the method of dissipative particle dynamics shows that to simulate the crystallization process, flexible-semi-flexible chains with thermodynamically incompatible blocks can be used.
Keywords: hydrogel, conjugated polymers, crystallization, mesoscopic modeling.
Belenkov M.E., Chernov V.M.
Crystal and electronic structure of 3-12 graphene functionalized by fluorine – page 406
Abstract: The structure and electronic properties of a new structural variety of fluorographene were calculated by the density functional theory method. Only one polymorphic variety of fluorographene based on graphene 3-12 is possible, in which all atoms are in equivalent structural positions. The hexagonal unit cell 3-12 of fluorographene contains 12 atoms, the sublimation energy is 13,77 eV/(CF), the band gap is 3,43 eV.
Keywords: graphene, fluorographene, ab initio calculations, crystal structure, electronic properties, polymorphism.
Blinov A.V., Yasnaya M.A., Blinova A.A., Shevchenko I.M., Momot E.V., Gvozdenko A.A., Senkova A.O.
Computer quantum-chemical simulation of polymeric stabilization of silver nanoparticles – page 414
Abstract: The paper presents the results of simulation the process of the silver nanoparticle stabilization with polyvinylpyrrolidone. The quantum chemical simulation was carried out in a QChem application using the IQmol molecular editor. At the first stage, models of the structures of polymer molecules and polymer complexes with silver were described. At the second stage, based on the designed models, the total energy of the polyvinylpyrrolidone-Ag system was calculated and the most energetically favorable type of interaction between silver atoms and polyvinylpyrrolidone was established. At the third stage, the spectral characteristics of the polyvinylpyrrolidone-Ag molecular complex were simulated and the obtained data were compared with the IR spectra of the synthesized polyvinylpyrrolidone-Ag samples.
Keywords: silver nanoparticles, polyvinylpyrrolidone, stabilization, computer quantum chemical modeling.
Bogdanov S.S., Myasnichenko V.S., Kolosov A.Yu., Sokolov D.N., Akimova Yu.N., Antonov A.S., Sdobnyakov N.Yu.
The features of the crystallization process in bimetallic nanostructures under external pressure – page 422
Abstract: In this paper the process of the structure formation in the bimetallic nanosystem Au – Ag of the equiatomic type at different external pressures has been investigated. It has been found that the external pressure affects the process of formation of the bcc phase only slightly, as does the size factor as well. At the same time, the ratios between fcc, hcp and icosahedral phases can vary significantly, under influence of both the external pressure and thesize effect.
Keywords: external pressure, crystallization, bimetallic nanostructures, molecular dynamics, external communication potential, structural transformations.
Vasilyev S.A., Kartoshkin A.Yu., Samsonov M.V., Dyakova E.V.
Melting of binary metal nanowires: molecular dynamics simulation – page 431
Abstract: In this paper a molecular-dynamic study of melting of binary metal nanowires with different initial composition and mesoscopic structure is carried out. For the Ni – Cu system it is shown that the melting temperature is significantly affected not only by the percentage of components, but also by their location in the particle, i.e. by the mesoscopic structure. Thus, the Ni nanowire coated with Cu atoms retains its stability at much higher temperatures than the Cu nanowire coated with Ni atoms, ceteris paribus.
Keywords: metal nanowire, Ni – Cu system, melting, size dependence, molecular dynamics.
Vasilyev S.A., Romanov A.A., Vostrov N.V., Skopich V.L., Savina K.G.
Molecular dynamics study of size dependences of melting and crystallization heats of platinum and palladium nanoclusters – page 436
Abstract: On the basis of the molecular dynamics results obtained by using the tight binding potential, the heats of melting, crystallization, and also the sublimation and evaporation heats of platinum and palladium nanoclusters were found. The obtained size dependences are linear if the inverse radius is chosen as an argument, which allows extrapolating the dependencies to the corresponding bulk phases and comparing with the tabulated values.
Keywords: platinum nanoclusters, palladium nanoclusters, molecular dynamics; tight binding potential, heat of melting, heat of crystallization, heat of sublimation, heat of evaporation.
Gafner Yu.Ya., Ryzhkova D.A., Zamulin I.S.
Estimating copper and gold nanoalloy applicability as an active layer of phase-inverse memory cells – page 443
Аbstract: In this work a method of computer simulation was used to study the process of the smooth cooling of nanoclusters of an alloy of copper and gold from the melt of various chemical compositions in order to analyze their applicability as the material of the active layer of phase-inverse memory cells. According to the results of the study, it was concluded that the optimal configurations are those with a gold content of 10% and 90% in the alloy with a particle size of 8 and 4 nm, respectively.
Keywords: phase-inverse memory, nanoclusters, computer simulation, gold, copper.
Gafner Yu.Ya., Gafner S.L.
Influence of chemical composition on the size of Cu – Au nanoparticles synthesized from the gas phase – page 449
Аbstract: The paper presents the results of a computer simulation by using a molecular dynamics method of synthesizing binary Cu – Au nanoclusters by condensation from a gaseous phase. To calculate the interatomic interaction forces, a modified tight-binding potentials with a fixed cutoff radius was used. The initial point of the process of condensation of nanoparticles from the gas phase was a configuration containing Cu and Au atoms (total number of 91124) distributed in a simple cubic lattice with the lattice parameter of 30aB, where aB is the Bohr radius (the periodic boundary conditions were used). For the analysis, we selected the initial configurations of different chemical compositions: Cu3Au, CuAu, Cu90Au10, Cu60Au40 which were cooled with the liquid nitrogen during the condensation process.
Keywords: nanotechnology, nanopowders, computer simulation, tight-binding, nanoparticles, copper, gold.
Greshnyakov V.A., Belenkov E.A.
Phase transformations of LA3 and LA5 diamond polymorphs – page 458
Abstract: Ab initio investigations of possible methods for obtaining diamond-like LA3 and LA5 phases, consisting of polymerized cyclobutane rings, were performed. It was established that LA3 phase can be obtained from L6 AA and L4-8 AA graphites at pressures from 50 to 67 GPa, whereas LA5 phase can be formed from L6 AB and L4-8 AB graphites at pressures from 45 to 71 GPa. In addition, LA5 phase can be obtained by strong uniaxial compressing of LA3 phase at pressures above 160 GPa.
Keywords: diamond, diamond-like phases, ab initio calculations, crystal structure, phase transitions.
Kartashynska E.S., Vysotsky Yu.B.
Quantum-chemical analysis of dimerization thermodynamics for carboxylic acids and aliphatic amines at the air/water interface – page 466
Abstract: In the frameworks of the quantum-chemical semiempiric PM3 method the thermodynamic parameters of the formation and dimerization processes are calculated for aliphatic amines CnH2n+1NH2 and carboxylic acids CnH2n+1COOH (n = 6-16). It was found that the spontaneous dimerization threshold for mixed associates of surfactants is carbon atoms in the 18-19 chain at 298 K. Formation of three types of mixed dimers from four is isoenergetic. They are mediate between corresponding pure dimers of amines and carboxylic acids. This suggests further formation of mixed 2D-film with the domain structure.
Keywords: aliphatic amines, carboxylic acids, enthalpy, entropy, Gibbs’ energy of dimerization, PM3 method.
Kotomkin A.V., Rusakova N.P., Turovtsev V.V., Orlov Yu.D.
Steric effect in difluorinealcane molecules – page 478
Abstract: Fifteen conformers of the CHF2 – (CH2)6 – CH3 molecule were found. Within a «quantum theory of atoms in molecules», their equilibrium geometry, total energies and the electron structure were studied. Analysis and comparison of electron parameters revealed in some structures a steric effect from CHF2.
Keywords: steric effect, electronegativity, quantum theory of atoms in molecules, electron charge density, fluorinealkanes.
Myasnichenko V.S., Samsonov V.M., Sdobnyakov N.Yu., Bembel A.G., Vasilyev S.A., Kolosov A.Yu., Savina K.G., Ershov P.M., Sokolov D.N.
Computer models of dealloying in binary metal nanoparticles – page 487
Abstract: Two alternative molecular dynamics models (programs) involving the Gupta (tight-binding) potential have been used to reproduce the dealloying phenomenon in the Au – Ag nanoalloy. Program I successively removes Ag atoms from the particle surface layer (we simulated nanoparticles consisting initially of 1500 Au and 1500 Ag atoms). Program II proposes search and removing atoms with lowest specific binding energies. We have found that as a result of dealloying the particle surface layer is really enriched with Au atoms. However the particle core keeps in general the structure of the initial nanoalloy. We have also established that dealloying results in formation a defected particle structure (vacancies, first of all). Presumably, just such an effect yields the porous structure of bigger Au – Ag particles in laboratory experiments on dealloying.
Keywords: dealloying phenomenon, molecular dynamics method, binary metal nanoparticles, segregation, defects, core-shell structures.
Myasnichenko V.S., Kolosov A.Yu., Shcherbatykh K.R., Sdobnyakov N.Yu.
Simulation of diffusion near the interface of metals in nanoalloys Co – M (M = Au, Cu, Pt) – page 500
Abstract: This paper presents results of molecular dynamics simulations for ordered configurations of cobalt nanoalloys. Atomic diffusion in Janus particles with a diameter of 3.6 nm was studied in the temperature range up to 1200K. It was found that the diffusion coefficient significantly depends on the composition of nanoparticles, namely on the degree of dimensional mismatch of the nanoalloy components. At the same time, the diffusion coefficient increases slightly when the relative number of vacancies doubles from 1% to 2%.
Keywords: cobalt-containing nanoalloys, volume and surface diffusion, interface, vacancies, molecular dynamics method, Janus particles.
Ryashentsev D.S., Belenkov E.A.
Ab initio calculations of the structure and electronic properties of BN layered compounds from sp- and sp2– hybritized atoms – page 511
Abstract: BN layers with a structure similar to that of graphyne were theoretically investigated by the density functional theory method in the generalized gradient approximation. The model structure of polymorphic varieties of BN layers was constructed on the basis of hexagonal boron nitride layers by replacing interatomic bonds with diatomic molecular BN fragments. As a result of theoretical analysis, the possibility of the existence of seven basic structural varieties of graphyne-like boron nitride has been established. However, with geometric optimization, only six polymorphs were stable. The structure of BN – L6 – γ3 polymorph was transformed into the structure of the initial BN – L6 layer. The sublimation energy of graphyne-like BN layers varies in the range from 16,29 to 17,00 eV/(BN), the width of the band gap is from 2,14 to 4,02 eV. The layered density of the BN layers varies from 0,33 to 0,58 mg/m2.
Keywords: boron nitride, ab initio calculations, crystal structure, electronic properties, polymorphism.
Sdobnyakov N.Yu., Samsonov V.M., Kolosov A.Yu., Vasilyev S.A., Myasnichenko V.S., Sokolov D.N., Savina K.G., Veselov A.D.
To the problem of stability/instability of bimetallic structures Co (core)/ Au (shell) and Au (core)/ Co (shell): atomistic simulation – page 520
Abstract: In this work, we performed atomistic modeling of the behavior of Co (core) – Au (shell) and Au (core) – Co (shell) during thermal exposure in order to study the stability/instability problem for the above nanostructures using the tight binding potential and two alternative computer programs based on the molecular dynamics and Monte Carlo methods. It has been shown that both the Co (core) – Au (shell) and Au (core) – Co (shell) structures can be stable. However, molecular dynamics results predict a short-term decay of Au2500 (core) / Co2500 (shell) nanostructures in a high-temperature region followed by a self-assembly, while the Monte Carlo method predicts the appearance of defects – cavities in the particle core and on the boundary between two components. It is concluded that the size effect can be the main factor determining stability/instability for the Co (core) – Au (shell) and Au (core) – Co (shell) structures.
Keywords: stability/instability, molecular dynamics method, Monte-Carlo method, binary metal nanoparticles, core-shell structures.
Ashkhotov O.G., Ashkhotova I.B., Aleroev M.A., Krimshokalova D.A.
Influence of heat treatment on the condition of thin-film system Cr + Ni on silicon – page 535
Abstract: Using Auger electron spectroscopy, an experimental study of the Si – Cr – Ni system was carried out. A comparative analysis of the results before and after exposure to thermal shock at the interfaces showed the effect of temperature on the distribution of elements over the thickness of the deposited layers. An increase in the number of thermal shocks leads to the fact that nickel remains on the surface of the silicon substrate, and chromium diffuses into silicon.
Keywords: analysis, substrate, distribution, spectrum, system, monochromaticity, energy analyzer, thermal shock, electron gun, temperature, diffusion, adhesion.
Bashkaykina A.N., Pan’kin N.A., Mishkin V.P.
Research of Al – SiC and Cu – SiC systems after forming of powder mixture – page 540
Abstract: This article presents the results of a study of the microstructure and density of powder materials of the Al – SiC and Cu – SiC systems. They are obtained by cold forming a mixture of powders of copper, aluminum and silicon carbide. A model for molding powder systems consisting of plastic (metal) and brittle (SiC) materials is proposed.
Keywords: molding, microstructure, powder body, porosity, density, mechanistic model, metal, silicon carbide.
Bogdanova E.A., Giniyatullin I.М., Pereverzev D.I., Razgulyaeva V.М.
Influence of reinforcement additives on sintering and hardening processes of nanoscale hydroxyapatite – page 548
Abstract: The article discusses a possibility of hardening nanostructured hydroxyapatite obtained by deposition from a solution, through the introduction of the reinforcement additive Al2O3, ZrO2, SiO2 (10, 15, 20, 30 wt.%). The influence of the qualitative and quantitative composition on sintering processes and strength characteristics of investigated samples has been shown.
Keywords: hydroxyapatite, composite biomaterials, ceramics, sintering, microhardness.
Bolotov A.N., Novikova O.O.
Lubrication properties of magnetic nanoliquids based on carboxylic acids – page 555
Abstract: We adduce technological characteristics of synthesis and properties of low-viscous magnetic lubricant nanoliquids with dispersion phase based on diester carboxylic acids. Some physical-chemical and tribological differential characteristic of the diester magnetic lubricant oils are presented. We researched the lubrication properties of the magnetic nanoliquids in various friction conditions and determine their peculiar characteristics. It was analized the influence of the series of antiwear additions on the friction.
Keywords: magnetic lubricant nanoliquid, friction, wear, lubricant, antifriction and antiwear additions.
Bolotov A.N, Novikova O.O
Magnetic properties of the magnetic nanodispersed lubricant oils – page 564
Abstract: In this work we adduce the results of the research of a magnetic properties of the magnetic lubricant oil in original condition and after triboeffects. We determined the parameters of the oil composition and structure changing in friction and causing the degradation it magnetic properties. The oils properties were measured with an original magnetometer with a Hall sensor.
Keywords: magnetic lubricating oils, friction, wear, lubricant, magnetic oil magnetization intensity, dispersion phase polarity.
Devitsky O.V., Kravtsov A.A.
Study of functional coatings of polyvinyl butyral with silver nanoparticles for photovoltaic converters – page 574
Abstract: Films of polyvinyl butyral with silver nanoparticles were obtained on the surface of solar cells. Spectral dependences of the external quantum yield of a solar cell at various concentrations of silver nanoparticles in a polyvinyl butyral film are presented. The largest increase in the external quantum yield of the solar cell (by 22,3%) in the spectral range 540-1040 nm was recorded at a concentration of silver nanoparticles in a film-forming solution of 7 mmol/L.
Keywords: plasmon resonance, silver nanoparticles, functional coatings.
Zlygosteva O.A., Sokovnin S.Yu., Ilves V.G.
Managing the textural properties of SiO2, SiO2 – MnO2, CaF2 nanopowders – page 582
Abstract: Physical and chemical properties of nanomaterials depend not only on the nature of the substance, but also on the size and shape of particles and pores. This paper investigates methods for managing the textural properties of nanopowders, obtained by pulsed evaporation by an electron beam in vacuum. The methods include doping at the stage of the nanopowder production, ultrasonic processing of aqueous suspensions of nanopowders and irradiating nanopowders with relativistic electrons.
Keywords: managing properties, porosity, nanopowder, silicon dioxide, fluorides.
Ivanova G.D., Myagotin A.V., Ivanov V.I.
Light induced lens in a transparent dense nanosuspension – page 590
Abstract: The light-induced concentration lens in a transparent dispersive medium at high radiation intensity was analyzed taking into account the interaction (repulsion) of nanoparticles. It is shown that the dependence of the light-lens response versus the intensity of radiation has the maximum due to the saturation of concentration of nanoparticles in the dense nanosuspension.
Keywords: light-induced lens, light-lens response, self-action of the radiation, electrostriction, nanosuspension.
Ivanov Yu.F., Petrikova E.A., Teresov A.D., Tolkachev O.S.
Structure and properties of surface layer of high-chrome austenitic steel borated by combined electron-ion-plasma method – page 596
Abstract: It was established that comprehensive surface treatment of 12Cr18Ni10Ti (AISI 321) high-chromium stainless steel, combining the electro-explosive alloying with titanium and boron and subsequent irradiation with an intense pulsed electron beam, allows the formation of a multiphase submicro- nanocrystalline surface layer up to 60 µm thick, whose microhardness and wear resistance exceed the initial state microhardness by 7 times, wear resistance – by more than 9 times.
Keywords: plasma, intense pulsed electron beam, austenitic steel, titanium, electroexplosive boration, phase composition, defective substructure, properties.
Klopotov A.A., Ivanov Yu.F., Petrikova E.A., Teresov A.D., Tolkachev O.S., Volokitin O.G., Klopotov V.D.
Saturation of the steal surface by titanium and boron electron-ion-plasma method: phase-structural composition – page 605
Abstract: The analysis of diagrams of the state of the Fe – B – Ti, Fe – Cr – B and Fe – Cr – Ti systems is carried out, describing the phase converting into high-chromium stainless steel of 12Cr18Ni10Ti (AISI 321) alloyed by titanium and boron. It is shown that in the conditions of the high-speed tempering realized at the electro-explosive alloying by titanium and boron and irradiation by an intensive pulsed electronic beam, compounds from two elements are formed in the steel only.
Keywords: austenitic steel, titanium, boron, state diagram, intense pulsed electron beam, electric explosive alloying, phase composition, defective substructure.
Krut’ko V.K., Musskaya O.N., Kulak A.I., Safronova T.V.
Thermal evolution of calcium phosphate foam ceramics obtained on the basis of hydroxyapatite and monocalcium phosphate of monohydrate – page 615
Abstract: The introduction of a 15 – 85 wt.% powder of monocalcium phosphate monohydrate Ca(H2PO4)2 · H2O into the hydroxyapatite suspension after annealing at 1200°C leads to the formation of resorbable calcium phosphate phases (tricalcium phosphate, calcium pyrophosphate), which makes it possible to control the phase composition of foam ceramics.
Keywords: calcium phosphate ceramic foam, hydroxyapatite, monocalcium phosphate monohydrate, thermal evolution, calcium pyrophosphate, tricalcium phosphate.
Nazarov A.D., Pan’kin N.A.,.Mishkin V.P.
Research of the powder system «titan – copper» after cold forming – page 624
Abstract: This article presents the results of a study of the microstructure and density of the material obtained after molding a mixture of powders of copper and titanium. Scanning electron microscopy indicates a slight deformation (mainly in the elastic region) of titanium particles and plastic – for copper grains. Scanning electron microscopy and density measurement results indicate the presence in the powder body of the volume occupied by the pores. The process of pressing a copper-titanium system is well described within the framework of a mechanistic model.
Keywords: mechanistic model, powder body, microstructure, density, pore space, pressing diagram.
Neustroev E.P., Prokopiev A R.
Properties of nanographite formed by plasma deposition and subsequent heat treatment – page 629
Abstract: The properties of nanographite flakes formed by the plasma deposition of methane CH4 on the SiO2 surface and subsequent heat treatment at 650°C were studied using Raman spectroscopy, atomic force microscopy and electrical measurements. From the results of studies, the formation of a carbon nanocrystalline structure with domain sizes of about 1,7 nm and a thickness of up to several nanometers was established.
Keywords: Plasma deposition, methane, heat treatment, nanographite, conductivity mechanism.
Petrik G.G.
Intermolecular potential curves – «companions» and forecast on their basis of the critical parameters – page 636
Abstract: An inflection point is entered in the description of the potential curve (PC). Taking into account the emerging possibilities, the potentials of Mi (n – 6) reduced by the properties of nine substances from globular molecules were analyzed. The observed inconsistencies in the shape of the WF6 potential was the starting point of the analysis that led to the new notion of companion PCs. It was found that the restored PC with low error is predicted to be critical temperature, and the PC companion is predicted to be critical volume.
Keywords: intermolecular interaction, model potential, potential curve, form factors, inflection point, Mi’s (n – m) potential, critical parameters, globula.
Sarkisov V.V., Logvinovich A.S., Shcherbakova V.B., Sadovskaуa L.Yu., Sviridova Т.V., Kapariha A.V., Sviridov D.V.
Structure and morphology control of metal-matrix composites by using redox-active nanophases – page 645
Abstract: The paper presents the results of a study of the possibility of creating metal-matrix composites «nickel – transition metal oxide», characterized by increased corrosion resistance, due to the targeted compaction of the metal matrix under the conditions of catalysis of electrocrystallization processes by oxide phases with controlled redox activity.
Keywords: metal – matrix composites, molybdenum trioxide, tungsten trioxide, vanadium pentoxide, electrochemical nickel coatings.
Skachkov V.М., Pasechnik L.А., Yatsenko S.P.
Low-melting non-toxic alloys as matrices of composite compounds for permanent connection of heterogeneous materials – page 654
Abstract: A number of diffusion-hardening composite solders for flux-free connection of heterogeneous materials are considered. The possibilities of changing the thermal expansion coefficient of connecting soldering joints are checked. The manufacturability of using solder pastes of different composition is shown and recommendations for connecting of heterogeneous materials are given. Joining of heterogeneous materials with the use of composite alloys by applying pastes at room temperature and subsequent low-temperature treatment (< 180 °C) with the production of vacuum-tight and durable joints finds wide application in new equipment (gyroscopes, optical quantum generators, solar panels, electronic systems, etc.). The introduction of heterodesmic compounds into the composition of composite materials allows one to obtain a connecting seam with a thermal expansion coefficient value, which is intermediate between the connected parts. Mechanochemical activation, ensuring the generation of non-equilibrium defect structures, makes it possible to dramatically improve the reactivity and synthesize new phases with a high chemical activity. A non-toxic tooth filling material has been created, which has a convenient manufacturability period and mechanical properties exceeding those of toxic amalgams, «metallogent»/silver amalgam: compression strength after 1 h 160 / 110 MPa; microhardness after 24 h 2000 / 1200 MPa. The compositions based on a matrix of gallium alloys with copper or copper with tin, zinc, silver, indium, bismuth etc. powders are hardened forming mainly medium-temperature (450 – 550 °C)) compounds.
Keywords: gallium, diffusion-hardening solder, flux-free soldering, powder, alloy.
Shikunov D.A., Simakov V.V., Sinev I.V., Shcherbakova E.A., Timoshenko D.A.
Recognition of organic vapors in air by variation operation mode of the gas sensor – page 665
Abstract: The results of experimental studies of sensitivity to organic vapors in air of the tin dioxide gas sensor are presented. It is shown that there is a fundamental possibility of recognizing organic vapors in air using a single chemoresistive sensor by varying temperatures of the operation heater.
Keywords: gas mixtures recognition, variation operating mode, gas sensors, tin dioxide thin films.
Aleroev M.A., Ashkhotov O.G., Ashkhotova I.B.
Kinetics of electronic spectra of surface of india with adsorbed oxygen – page 6
Abstract: The spectra of Auger and plasmon losses of polycrystalline indium before and after aging in an oxygen medium have been studied. The kinetics of electronic states on the surface of indium with adsorbed layers of oxygen (exposure in an oxygen medium up to 5000 Langmuir and at atmospheric pressure at room temperature) is studied. It is shown that aging in an oxygen medium leads to the formation of an ordered oxide layer consisting of In2O3+In+O.
Keywords: surface, adsorption, indium, oxide, energy, spectroscopy, oxygen, analysis, ion, bond, atom.
Antonova E.S., Pastushenkov Yu.G.
Features of the low-temperature transformation in the micromagnetic structure of the intermetallic compound Ho2Fe17 – page 13
Abstract: We found that a three-phase micromagnetic structure may emerge when a magnetic field is applied to the intermetallic compound Ho2Fe17 with the magnetic crystallographic anisotropy of the «easy plane» type in the temperature range 10 ÷ 110 К. Using the method of magneto-optic Kerr effect, the temperature dependence of the field value where the third magnetic phase emerges was determined.
Keywords: micromagnetic structure, magnetic anisotropy of the type «easy plane», rare-earth intermetallic compounds, three-phase magnetic structure.
Apekov A.M., Shebzukhova I.G.
Polarization and dispersion corrections to the interfacial energy of the facets at the boundary between calcium/barium crystals and nonpolar organic liquids – page 20
Abstract: In this paper we have obtained polarization and dispersion corrections to the interfacial energy of the faces at the boundary between calcium and barium crystals of low-temperature modifications and nonpolar organic liquids using the electron-statistical method. We have shown orientation dependence of the corrections and interfacial energy of the crystals in view of polarization and dispersion corrections.
Keywords: interfacial energy, polarization correction, dispersion correction, electron-statistical method, nonpolar organic liquid, barium, calcium.
Aref`eva L.P., Shebzukhova I.G.
Wetting and anisotropy of interfacial energy on the contact boundary of indium nanocryctals and orientied substrate – page 27
Abstract: We propose a technique for estimating the wetting and anisotropy of the interfacial energy at the interface between the metal particles (indium) with a substrate based on the construction of the Winterbottom equilibrium shape of the crystal. The effective contact angle and the ratio of interfacial energies at the particle-substrate interface are calculated from the experimental data of the geometric characteristics of the particles obtained by analyzing the AFM images of the samples. The obtained dependences are qualitatively consistent with thermodynamic states and known data for other systems.
Keywords: interface energy, wetting, nanocrystals, indium, Winterbottom analysis, atomic-force microscopic.
Aref`eva L.P., Shebzukhova I.G.
The interfacial energy of metalic thin films on the boundary with liquid polar dielectric – page 35
Abstract: Expressions have been obtained for estimating the interfacial energy of metallic thin films at the interface with an organic dielectric coating. The case of the boundary of the contact of cobalt films with polyatomic alcohols (diols) is considered. Comparison with the experimental data shows a good agreement between the theoretical model and real objects.
Keyword: interface energy, polyatomic alcohols, thin films, polar organic dielectric.
Ataeva A.Yu., Sverdlik G.I., Kambolov D.A., Ataev A.R.
Modern methods of granulometric analysis of dusted materials containing nanoparticles – page 44
Abstract: In the work the differential and integral distribution of particles of dolomite flour and wings of zinc-containing welsh furnaces by size was studied by the method of analytical disk centrifugation with X-ray detection. The results of measurements for large particles in the regime of natural sedimentation G and for small particles, including nanoparticles, are considered in the centrifugation regime X.
Keywords: granulometric analysis, sedimentation regime, centrifugation mode, basis of weighing, nanoparticles, detection principle.
Akhmedov E.N.
Gold nanocrystal properties dependence on size and shape at isobaric conditions – page 53
Abstract: Using the nanocrystal RP-model, the state equation of a gold was calculated. On the basis of this equation the isobaric dependence of the melting temperature on the size and shape was obtained at P = 0. It is shown, that the stronger the shape of the nanocrystal deviates from the most energetically effective one, the bigger the size of the nanocrystal at the crystallization start point. Approximation of such points for various shapes made it possible to determine the crystallization start temperature of the Au macrocrystal: Tcr(N = ∞, P = 0) = 921K, which coincided with the rule of Turnbull.
Keywords: equation of state, nanocrystal, gold, size, shape.
Baidyshev V.S.
Computer simulation of the Cu@Si core-shell nanoparticles formation – page 64
Abstract: In this work computer simulation of the condensation processes of Cu-Si core-shell nanoparticles was performed by the molecular dynamics method. It was shown that simultaneous cooling of atomic vapors of copper and silicon leads to the formation of disordered CuSi alloy particles. A possible mechanism for the formation of nanoparticles (Cu – core, Si – shell) is associated with deposition of small silicon clusters onto a pre-formed copper core.
Keywords: computer simulation, molecular dynamics, core-shell nanoparticles, condensation.
Barakhtin B.K., Sedletsky R.V.
Peculiarities of structural variations at crystallization of highly filled composites on polymeric basis – page 73
Abstract: Composite samples with polymer matrixes of different compositions are investigated. The volume fraction carbon fillings of globular form quasi-isotropically distributed in the samples was found to range from 0.4 to 0.7. Under increasing the density, the modulus of elasticity and strength of the composites under discussion, some the quasi-periodical oscillations of mechanical parameters are discovered accompanied by changing both the value and sign of the Poisson coefficient. The nature of this phenomena has been established and a model of the structural variations has been proposed.
Keywords: polymer composite materials, mechanical tests, Poisson coefficient.
Bembel A.G., Talyzin I.V., Samsonov V.M.
Solid state wetting and dynamics of solid surface nanorelief – page 83
Abstract: Using molecular dynamics solid state wetting in the Cu (nanoparticle) / Cu (substrate) system was studied. It has been found that the solid state spreading mechanism corresponds, first of all, to the surface diffusion that was confirmed by the linear dependence of square radii of the first monolayer on the spreading time. A hypophysis was put forward and justified that the degradation of nanorelief of the solid surface occurs by means of the solid state wetting mechanism.
Keywords: solid state wetting, surface diffusion, nanoparticle, surface, nanorelief, molecular dynamics.
Bernatskii D.P., Pavlov V.G.
The effect of carbon on the diffusion of cesium on the renium surface – page 93
Abstract: The diffusion of cesium over the rhenium surface and the rhenium surface coated with carbon was studied by methods of the field electron and desorption microscopy. The method of continuous field desorption was used, in which surface diffusion ensures the flow of the adsorbate to the desorption site. It was found that the carbon-coated surface undergoes intensive diffusion of cesium, while there is no diffusion on the rhenium surface.
Keywords: surface diffusion, alkali metals, electric field, carbon, rhenium.
Bernatskii D.P., Pavlov V.G.
Application of the method of field desorption of sodium for studying carbon nanostructures on the surface of rhenium field emitter – page 99
Abstract: Field desorption microscopy was used to study the surface of the rhenium field emitter after its carbonization. Field electron and field desorption images of the surface after carbonation at adsorption of sodium atoms are obtained. On the basis on the analysis of modifications of the field electron and field desorption images of the surface at different values of the electric field we concluded that formation on the surface of the carbonized rhenium of bulk graphite nanostructures affects the emission processes.
Keywords: field desorption microscopy, electric field, field emitter, alkali metals, carbon nanostructures.
Berov Z.Zh., Manukyants A.R., Kasumov Y.N., Sozaev V.A.
Fhase forming and structural feature twu-layer coating «titanium/nichrome» on artificial polycrystalline diamonds – page 106
Abstract: The phase forming and the structural features of two-layer coating «titan/nichrome» on the surface of artificial polycrystalline diamonds ASB-4 are examined. The film was deposited by method of ion-plasma vacuum 10-2 Pа evaporation. The X-ray-phase film analysis indicated that at the surface the phases Ni4Ti3, Cr7Ni3, Cr2Ti, Cr0,875Ti0,125, NiTi and others are organized. In the films it is seen the fomation of spherical phases, conceivably Cr0,075Ti0,125. On diamond films, obtained by recuperation, the structural patterns are seen which are typical for Zn.
Keywords: phase forming, ion-plasma metallization, recuperation, diamonds.
Blinov A.V., Snezhkova Yu.Yu., Yasnaya M.A., Dyudyun O.A., Kaznacheev Y.V., Shevchenko I.M.
Comparison of the ζ-potential measuring methods accuracy for the colloidal particles – page 115
Abstract: The study is devoted to the choice of an optimal method for determining the ζ-potential of colloidal SiO2 particles. The electrokinetic potential was measured using two methods: (i) acoustic and electro-acoustic spectroscopy; (ii) horizontal agarose gel electrophoresis. Based on experimental and calculated data, an optimal method for measuring the ζ-potential of colloidal SiO2 particles was chosen.
Keywords: ζ-potential, electro-acoustic spectroscopy, electrophoresis, absolute error, relative and normalized error, distribution of the mean square deviation.
Bobreva L.A., Masloboeva S.M., Sidorov N.V., Palatnikov M.N.
Obtaining and investigation of the structural features of the LiNbO3:Zn (2,12 wt. % Zn) single crystal – page 124
Abstract. We carried out preparation of homogeneously doped charge LiNbO3:Zn ([Zn] = 2,44 wt. %) of congruent composition (ratio [Li]/[Nb]=0,96). From this charge a LiNbO3:Zn (Zn ~ 2.12 wt. %) single crystal by the Czochralski method was grown. Defect complexes (VLi)—-OH— of the LiNbO3 cong and LiNbO3:Zn crystals were discovered by IR-absorption spectroscopy in the area of stretching vibrations of OH—-groups.
Keywords: homogeneous doping, charge, single crystal, lithium niobate, stretching vibrations of OH——groups.
Bogdanova E.A., Skachkov V.M., Shirokova A.G., Sabirzyanov N.A.
The use of different forms of hydroxyapatite to create a bioactive coating on a porous titanium-base – page 133
Abstract: The article discusses methods of creating a bioactive composite on a porous titanium base. The possibility of formation of coatings based on colloidal hydroxyapatite and an aqueous suspension of powder hydroxyapatite in various ways has been studied. The adhesive properties of the obtained coatings are estimated.
Keywords: biocomposites, functional bioactive coating, strength properties, hydroxyapatite, porous titanium.
Bogdanova E.A., Skachkov V.M., Sabirzyanov N.A.
Study of the influence of anionic substitution in hydroxyapatite structure and properties of ceramics on it based – page 142
Abstract: The article discusses the possibility of strengthening stoichiometric hydroxyapatite obtained by precipitation from the solution by partial substitution of phosphate groups with silicate ions. Such characteristics of samples as phase composition, morphology, particle size distribution, specific surface area have been studied. It was established that the degree of substitution affects the mechanical properties of synthesized powders and ceramics after annealing.
Keywords: hydroxyapatite, silicon-substituted hydroxyapatite, biocomposites, microhardness.
Bolotov A.N., Novikov V.V., Novikova O.O.
Hard lubricant ceramic coatings with nano- and microdispersed filler – page 150
Abstract: A basis was developed for a technology of the solid lubricant ceramic coatings with antifriction filler. We have made physical, mechanical and tribotechnical tests of the received materials and gave a recommendation for their practical application.
Keywords: composite ceramic coatings, hard lubricant materials, antifriction fillers, nanodispersed particles, friction, wear.
Bolotov A.N., Novikov V.V., Novikova O.O.
Lubricating oils on the basis of nanoliquids – page 159
Abstract: We established applicability of dispersed medium based on diesters of carbonic acids for production the low-viscosity magnetic oil of new generation. It was shown unusual approach to select surfactant-stabilizer for colloidal structure of oils considering their dielectric properties and friction effects. It was submitted the preselection findings of the additions and fillers for magnetic oil which are characterized by the different mechanism of reducing friction.
Keywords: magnetic lubricating oil, friction, wear, lubricant, dispersed medium, dispersed phase, antifriction and wearproof additives.
Bolshakova N.N., Bolshakova О.V., Ivanov V.V., Ivanova T.I., Semenova E.M.
Niobium-containing barium titanate crystals switching processes – page 169
Abstract: The results of research of the processes of polarization of niobium-containing crystals of barium titanate in changing electric fields are presented. It has been established that the time for reorganization of the ferroelastic domain structure is 30-40 times shorter than the switching time of the total polarization of the crystal, which indicates that the main switching time of BaTiO3 : Nb5+ crystals is determined by the change in its ferroelectric 180° domain structure.
Keywords: processes of switching, domain structure, barium titanate, polarization-optical method, Barkhausen effect.
Brylkin Yu.V., Zalogin G.N., Kusov A.L., Rudin N.F.
The error in probe measurements of heat flux dissociated gas streams – page 178
Abstract: The main error in strongly dissociated laminar gas jets (nitrogen, air, CO2) affecting the measured heat flux is the surface catalytic activity of the heat-receiving element with respect to the reactions of the heterogeneous recombination of atoms. The purpose of this work is to estimate the heat flux measurement errors due to the influence of the surface layer area on the micro-and nanoscale.
Keywords: catalytic activity, surface structure, heat flux.
Burtsev A.A., Butkovsky O.Ya.
Modeling fractal crystals forming on the surface of stainless steel by cellular automata – page 187
Abstract: In this paper experiments on crystallization from melts and results of analysis of the morphology of formed crystal structures are discussed. Some examples of forming complex dendritic formations are shown. Different types of the crystal morphology arise in dependence on the duration of heating and the energy of the acting radiation. Models of the distribution of crystallization centers and the growth of an individual cluster under the diffusion process were modelled by the methods of cellular automata. The relationship between the morphology and the model parameters is analyzed.
Keywords: laser heating, metal surface modification, crystallization, fractal, dendritic crystals, diffusion-limited aggregation, cellular automata.
Vazirov R.A., Sokovnin S.Yu., Ilves V.G.
Antioxidant properties of cerium dioxide nanoparticles – page 196
Abstract: Studies of biological activity of cerium dioxide nanoparticles show that this compound exhibits antioxidant, antitumor, antibacterial and antiviral properties. The cerium dioxide nanoparticles were obtained by evaporation of a target by a pulsed electron beam in a low-pressure gas with a specific surface area of 190 m2/g. To determine the enzyme-like activity of cerium dioxide nanoparticles, chemical analysis of interaction with the hydrogen peroxide was carried out. The results show an active inhibition of reactive oxygen species at pH above 6.
Keywords: nanopowder, nanoparticles, suspension, cerium dioxide, reactive oxygen species, antioxidant.
Vasilyev S.A., Kartoshkin A.Yu., Samsonov M.V., Dyakova E.V.
Melting of metal nanowires: molecular dynamics simulation – page 204
Abstract: A comparative molecular dynamics study has been carried out of the melting of infinite metallic nanowires and free spherical metallic nanoparticles of the same diameter. It was found that the nanowire is melted at a higher temperature than its spherical analogue as the shape of the nanowire is non-equilibrium. As a result, the melting of the nanowire leads to the loss of its stability, i.e. to the break of the nanowire.
Keywords: metal nanowire, melting, size dependence, molecular dynamics, free nanoparticle.
Gafner Yu.Ya., Gafner S.L., Redel L.V.
Nanostructures as a material for phase-inverse memory – page 210
Abstract: Despite on long researches, chalcogenide alloys are still generally used in the contemporary PCM layouts as the operating layer material undergoing structural transformations. However, the evolution of the technique aimed at the creation of new non-volatile arrays of information requires different technical solutions. First of all, it deals with the reduction of one bit storage area to several nanometers and reduction of the access time, in particular the possible application in the PCM memory of small metallic nanoclusters.
Keywords: phase transition, memory cells, nanostructures.
Gafner Yu.Ya., Bashkova D.A., Gafner S.L., Redel L.V.
Evaluation of applicability of small silver nanoparticles as the cells of PCM memory – page 219
Abstract: In this paper, one of the aspects of using metallic nanoclusters was considered, namely the use of silver nanoparticles as separate bits of information in memory devices based on the phase-change memory (PCM) method. The basic principle of this approach is that to locally change the phase state of a memory cell from crystalline to amorphous, keep this phase as long as you like and, if necessary, and return the material to its original crystalline state. Based on the results of simulation of silver nanostructures, it was concluded that their use as a memory element based on phase transitions is allowed, but with a particle size limitation exceeding 8.0 nm.
Keywords: phase transition, memory cells, silver, nanoclusters.
Gafner Yu.Ya., Bashkova D.A., Gafner S.L.
Using nanoparticles of Ag – Cu alloy as separate bits of PCM memory – page 226
Abstract: One of the promising areas of application of metallic nanoparticles is the creation of devices on their basis with a high information recording density that generates interest in the study of their magnetic, optical and structural-phase properties. In this paper, one of the aspects of using metallic nanoclusters. Namely we mean the use of silver-copper nanoparticles as separate bits of information in memory devices based on the phase-change memory.
Keywords: phase transition, memory cells, silver, copper, nanoclusters.
Grebenyuk G.S., Lobanova E.Yu., Pronin I.I.
The influence of the intercalated silicon on the graphene electronic structure – page 234
Abstract: Intercalation of the graphene-cobalt system with silicon was investigated experimentally. The ab initio calculation of the electronic structure of a low-dimensional graphene-silicon-cobalt system was carried out using the density functional theory. The most advantageous positions of intercalated Si atoms are determined. It is shown that the introduction of silicon under graphene leads to a sharp decrease in the interaction of carbon atoms with the substrate.
Keywords: graphene, intercalation, cobalt silicides, DFT calculations, thin films, photoelectron spectroscopy.
Ershov P.M., Kolosov A.Yu., Myasnichenko V.S., Sokolov D.N., Khort A.A., Bogdanov S.S., Shimanskaya H.N., Sdobnyakov N.Yu.
Invetigation of size dependences of melting and crystallization temperatures and specific excess surface energy of nickel nanoparticles under melting / crystallization phase transition – page 242
Abstract: The Monte Carlo method was used to study size dependences of the melting and crystallization temperatures of nickel nanoparticles, their hysteresis area, and changes in the specific excess surface energy during the direct and reverse melting/crystallization phase transition. Simulation results for nickel nanoclusters indicate the presence of melting and crystallization temperature regions, which generally correlates well with simulation results for other metals. We employed simulation by using the embedded atom model and tight-binding Cleri-Rosato potential. Results of three series of computer experiments for the size dependences of the melting and crystallization temperatures made using the two interatomic potentials in the software package LAMMPS and our own softwares were found to be in good accordance between themselves.
Keywords: nickel nanoparticles, Monte-Carlo method, Gupta potential, size dependences, melting and crystallization temperatures, specific excess surface energy.
Efremov V.V., Shcherbina O.B., Radyush Yu.V., Palatnikov M.N.
Microstructure, phase states, dielectric and elastic properties of ceramic solid solutions Li0,17Na0,83NbyTa1-yO3 obtained at high pressure – page 252
Abstract: Microstructure and elastic properties of ferroelectric ceramic solid solutions Li0,17Na0,83NbyTa1-yO3 with a perovskite structure were investigated, obtained by thermobaric synthesis at high pressures and temperatures. The electrical characteristics and phase states of a series of ferroelectric high-pressure solid solutions Li0,17Na0,83NbyTa1-yO3 ( y = 0,1 — 0,5 ) were investigated by the impedance spectroscopy method. Some anomalies are revealed in ε'(T) and σsv(T) dependencies associated with phase transitions in the studied ceramic samples. The values were established of the static conductivity as a function of the temperature and enthalpy of activation of charge carriers. It was found that Li0,17Na0,83NbyTa1-yO3 is a high-temperature superionic.
Keywords: solid ferroelectric high-pressure solutions, microstructure, Young’s modulus, impedance spectroscopy, dielectric permittivity, electrical conductivity.
Zlygosteva O.A., Sokovnin S.Yu., Il’ves V.G.
The use of SiO2 — MnO2 nanopowders for targeted drug delivery – page 262
Abstract: Application of manganese-doped mesoporous silica nanopowders SiO2 — MnO2 for targeted drug delivery was researched. It has been established that an increase in sonicated time leads to changes in the NP structure. The produced nanopowders have a high loading capacity 0,09 mg of Amoxicillin per mg of nanopowder, 0,075 mg of Doxorubicin per mg of nanopowder that is five times higher than the loading capacity of chemically synthesized nanopowders.
Keywords: mesoporous silica nanopowder, dopant manganese dioxide, targeted drug delivery.
Ivanov V.V., Golubeva E.N., Sergeeva O.N., Nekrasova G.M., Pronin I.P., Kiselev D.A.
Peculiarities of the process of switching polarization in polycrystalline thin films of lead zirconate-titanate – page 270
Abstract: The paper presents the results of a study of relaxation of the dielectric permittivities in constant electric fields upon switching the polarization of thin films of lead zirconate-titanate, crystallized at different annealing temperatures. It is shown that the relaxation processes are characterized by at least three relaxation times which depend on the crystallization temperature. It is shown that the relaxation processes depend on the localization of lead oxide in the bulk of the film.
Keywords: thin films of lead zirconate-titanate, dielectric permeability, relaxation time, crystallization temperature, lead oxide.
Ivanov V.I., Ivanova G.D., Mjagotin A.V.
Thermodiffusion contribution in the thermal lens response of the nanosuspension – page 280
Abstract: A new two-beam configuration of the thermal lens method for the nonlinear optical diagnostics of nanosuspensions is presented. The proposed configuration eliminates the influence of the electrostrictive response and thus provides the determination of thermodiffusion coefficient of nanoparticles.
Keywords: thermal lens response, nanosuspension, thermodiffusion, electrostriction.
Ivanov V.I., Ivanova G.D., Krylov V.I., Khe V.K.
Sedimentation of nanoparticles under the action of light pressure forces in liquid media – page 286
Abstract: A model of sedimentation of nanoparticles in a uniform light field is considered as an alternative to methods of precipitation in a gravitational field and centrifugation. The exact analytical solution of the one-dimensional nonstationary mass transfer problem in a bounded cell is given. The main parameters of the centrifugal and light-induced sedimentations of nanoparticles are compared.
Keywords: sedimentation, dispersed media, light pressure.
Ivanov D.V., Antonov A.S., Sdobnyakov N.Yu., Shimanskaya H.N., Romanovskaia E.V., Afanasiev M.S.
About «technological» properties of nano-sized nickel and copper films – page 291
Abstract: As an example of studying morphology of the relief of nickel and copper nano-sized films on the mica surface, it is possible to create a technology to «grow» structures with a given surface morphology using a scanning tunneling microscope. The characteristic features of the film surface nanorelief are described, including fractal properties. The current-voltage characteristics of a metal-to-metal contact for nickel and copper films with a tungsten tip are obtained. It is shown that for surface areas containing fractal structures, the current-voltage characteristics may differ from the dependences obtained on ordinary surfaces.
Keywords: scanning tunneling microscopy, nanorelief, fractal dimension, nanoscale films of nickel and copper, current-voltage characteristic, tunnel contact.
Ivanov Yu.F., Denisova Yu.A., Petrikova E.A., Teresov A.D., Lykov S.V., Ivanova О.V., Klopotov A.A.
Combined method of diffusion saturation of steel by nitrogen – page 304
Abstract: The results obtained during the study of 20H13 steel subjected to a combined treatment including irradiation with a pulsed electron beam and nitriding in a plasma of a low-pressure gas discharge are presented. It is shown that nitriding of steel previously irradiated with an electron beam makes it possible to increase in 1,8 times the microhardness of the surface layer of 140 μm in thickness on the original sample and in 1,4 times on the sample after nitriding.
Keywords: intense pulsed electron beam, nitriding, gas discharge plasma, nanoparticles, phase composition, defective substructure, properties.
Izmailov V.V., Novoselova M.V.
On nanotopographic parameters of engineering surface and its profile – page 313
Abstract: Amplitude and spacing parameters of engineering surfaces nanotopography and some their correlations have been considered in comparison with similar parameters and correlations on a microscale level (microroughness). It is shown that on a nanoscale level theoretical and empirical relations characterizing a surface topography on a microscale level hold true.
Keywords: surface, topography, nanoroughness, microroughness, amplitude parameters, spacing parameters, correlations.
Ilves V.G., Sokovnin S.Yu., Zayats S.V., Murzakaev A.M., Demina Т.М., Zuev M.G.
Properties of compacts from BaF2 nano-powder obtained by pulsed electron beam evaporation – page 322
Abstract: In this work, a mesoporous crystalline BaF2 nanopowder with specific surface area (Sred) up to 34,8 m2/g was obtained by evaporation of targets of a micron BaF2 powder (Sred = 0,38 m2/g) of optical purity with a pulsed electron beam. Textural and thermal features of BaF2 nanopowder (before and after annealing at 200°C in air) and individual properties of compacts made from BaF2 nanopowder by pulsed magnetic pressing and static pressing are studied. By means of pulsed magnetic pressing in vacuum at a temperature of about 425°C, vitreous, opaque compacts of black color, promising for use as scintillators and dosimeters, were obtained. The effect of pressing methods on the cathodoluminescence and photoluminescence characteristics of compacts from BaF2 is studied.
Keywords: pulsed electron beam evaporation, nanocrystalline barium fluoride, textural and thermal properties of BaF2 nanopowder, luminescence of compacts from BaF2 nanopowder.
Kandaurov M.V., Vladimirova E.V., Dmitriev A.V.
Sol-gel fabrication, morphology and magnetic properties of multiferroics BiFe1-xMnxO3 – page 330
Astract: Experimental data on the synthesis and properties of the solid solution BiFe1-xMnxO3 are given. The length of the solid solution (0 ≤ x ≤ 0,20) was established, the morphology of the particles and magnetic properties of the samples were investigated in dependence on the content of a dopant. Nonlinear concentration dependences of magnetic characteristics for BiFe1-xMnxO3 with a maximum at the manganese 5 — 7 mol. %. content were found.
Keywords: bismuth ferrite, doping, sol-gel method, morphology, agglomerates, solid solution, phase composition, magnetic properties.
Karpenkov A.Yu., Dunaeva G.G., Rakunov P.A., Semenova E.M.
Method of analysis of the reversal magnetization processes using magnetic domain structure images – page 338
Abstract: A unique software and hardware system for obtaining and automatic analysis of the magnetic domain structure images in an external magnetic field for further study of the magnetization reversal process was developed. The method efficiency and possibility of its use for studying the magnetization reversal of local surface regions of magnetic materials are shown, using the experimental magnetization curves of an yttrium-iron garnet film.
Keywords: magnetic domains, magnetization reversal, magnetization curves, magnetic films, yttrium-iron garnet.
Kiseleva M.A., Sokovnin S.Yu., Balezin M.E.
Producing nanodimensional silver covering on aluminum oxide nanopowder – page 345
Abstract: The principal possibility of the composite particles production by the radiation-chemical method was shown. The composite particles were obtained in the nanoscale range ( 60 — 80 nm) from aluminum oxide partially coated with silver. The coating percentage was from 2 — 3% to 16 — 40%. The high efficiency of the production method was demonstrated. The ability to control the deposition process and the type of silver coating by changing the deposition time had also been established.
Keywords: radiation technology, nanoparticles, silver-coated alumina.
Knat’ko M.V., Lapushkin M.N.
Violation of the energy distribution of desorbiting ions Na+ in thermal ionization on the surface of NaAuy alloy – page 352
Abstract: The effect of the applied external electric field on the energy distribution of desorbed from the alloys are presented. It is shown that the energy distributions of the desorbed depend on the distribution of positive charge carriers near the surface that, in turn, depends on the external electric field.
Keywords: thermal ionization, adsorption, surface states, intermetallic alloys.
Kolosov A.Yu., Myasnichenko V.S., Bogdanov S.S., Romanovskiy V.I., Nepsha N.I., Shcherbatykh K.R., Sdobnyakov N.Yu.
On the regularities of formation of mono- and bimetallic nanoparticles in the coalescence process – page 359
Abstract: The simulation was carried out using two alternative Monte Carlo and molecular dynamics methods of the coalescence process with gradual thermal action for metallic nanoparticles based on nickel, aluminum, copper, silver and gold. The following types of mono- and bimetallic systems were considered: in the form of a sphere and in the form of two perpendicular blocks. It is established that the evolution of the coalescence process for monometallic nanoparticles differs significantly from that for bimetallic nanoparticles. Characteristics such as the coalescence temperature, the structure and shape of the neck, the dihedral angle between the nanoparticles can differ significantly. It is argued that it is impossible to accurately predict the behavior of a bimetallic system in the process of coalescence, knowing the evolution of the process of coalescence for monometallic systems consisting of the same metals.
Keywords: mono- and bimetallic nanoparticles, molecular dynamics, coalescence, Monte-Carlo method, molecular dynamics, dihedral angle.
Kotomkin A.V., Rusakova N.P., Turovtsev V.V., Orlov Yu.D.
Electronic integral characteristics of groups in the fluoro-substituted of isobutan and neopentan – page 368
Abstract: Within a «quantum theory of atoms in molecules» (QTAIM) the equilibrium geometry and the electron structure of fluoro-substituted molecules (CH3)2−CH−CH(3-n)Fn and (CH3)3−C−CH(3-n)Fn, where 1 ≤ n ≤ 3, were studied. Intramolecular interactions also discussed.
Keywords: branched fluorinealkanes, electronegativity, quantum theory of atoms in molecules, electron charge density, steric effect.
Krut’ko V.K., Kulak A.I., Musskaya O.N., Safronova T.V., Budeiko N.L.
Calcium phosphate foam ceramics with regulated bioactivity – page 374
Abstract: The introduction of a 10−50 mass.% of brushite powder or tricalcium phosphate heated at 50−70°C in a hydroxyapatite slip leads after annealing at 1200°C to formation of resorbable calcium phosphate phases which make it possible to regulate the degree of bioactivity of the foam ceramics.
Keywords: calcium phosphate foam ceramics, hydroxyapatite, brushite, tricalcium phosphate, bioactivity.
Kuznetsov Yu.A., Lavrovskaya N.P., Rut’kov E.V., Gall N.R.
Temperature effect on electron-stimulated desorption of cesium atoms from graphene on iridium – page 383
Abstract: Electron-stimulated desorption of cesium atoms from monolayer graphene on iridium has been observed at 160 K and 300 K. Migration processes have been shown to be frozen at 160 K, and cesium atoms to be located only at the graphene surface. At 300 K, due to intercalation an additional layer of cesium atoms is produced and located under the graphene layer. We believe that observed electron-stimulated desorption of cesium atoms is due to the non-metal nature of the adsorbed graphene film independently on the metal nature under it: iridium or cesium.
Keywords: electron-stimulated desorption, graphene, intercalation.
Kuznetsov Yu.A., Lapushkin M.N.
Electron-stimulated desorption of Cs atoms from graphene on Ir: experiment and model – page 393
Abstract: The processes of electron-stimulated desorption of Cs atoms from the graphene film on the iridium ribbon have been studied. The model of the Cs atom electron-stimulated desorption processes from the graphene film have been suggested. It has been shown the community and the difference of the electron-stimulated desorption processes for high-energy and low-energy peaks in the kinetic energy distributions of the desorbed atoms.
Keywords: electron-stimulated desorption, adsorption, alkali metals, graphene.
Kul’kov V.G., Syshchikov A.A.
Intergranular slippage on faceting boundaries with a bimodal distribution of facet dimensions – page 401
Abstract: The speed of mutual displacement of the grains along faceting boundary with two characteristic sizes of facets under the external shear stress is considered. Based on the solution of the stationary equation of diffusion of vacancies at the grain boundary, the distribution of their concentration and normal stresses along the facets is found. The presence of smaller facets leads to an increase in the speed of intergranular slippage.
Keywords: faceted grain boundaries, intergranular slippage, vacancies, diffusion.
Kumykov T.S., Nagaplezheva R.R.
The influence of the filler on the surface tension of a binary mixture of butadiene nitrile rubber (SKN-26) with polyvinyl chloride (PVC) – page 408
Abstract: The effect of the concentration of carbon black and aluminum oxide nano-additives on the surface tension of polymer-composite materials SCN-26 and PVC was investigated by the neutral drop method. Extreme changes in properties of the materials under study depending on the composition are found, which are explained by the effects of redistribution of high — and low-molecular fractions on the surface of the filler and colloidal chemical phenomena in the binary polymer mixture.
Keywords: neutral drop method, nanoparticle, filler, interphase phenomenon, polymer matrix.
Kurbanova E.D., Polukhin V.A.
Structure – dynamic effects in metal melts, glasses and nanocrystals in dependence of temperature – page 414
Abstract: The researchers have conducted a comprehensive analysis of both the original material characteristics and the available information on phase-structural transformations during cooling, glass transition and crystallization of melts, with detailed tracking of their ordering with using the methods as synchrotron X-ray diffraction, scanning electron microscopy, differential scanning calorimetry measurements, and with the interpretation of data by molecular dynamic simulation and thermodynamic calculations.
Keywords: melts, amorphous alloys, glass transition, X-ray diffraction, differential scanning calorimetry, medium order, structural factor, heat capacity, hidden liquid transitions, viscosity, diffusion, crossover.
Kushnarev B.O., Khludkova L.S.
Gas-sensitivity of tin dioxide thin film to kerosene vapours at room temperature – page 420
Abstract: The results of experimental studies the gas sensitivity of SnO2 thin films to kerosene vapor at room temperature in an atmosphere of dry and wet air are presented. The presence of water vapor in the surrounding atmosphere does not significantly affect the gas sensitivity of thin films to kerosene vapor. It is suggested that the process of oxidation of unsaturated hydrocarbons on the surface of tin dioxide has an autocatalytic character.
Keywords: gas-sensitivity, tin dioxide, thin films, kerosene vapors, room temperature.
Laipanov M.Z., Manukyants A.R., Sozaev V.A., Khubolov B.M.
Diffusional interaction in tin film – nickel base system – page 427
Abstract: In this work a Sn film was deposited on the nickel base of NP-2 sort in vacuum and bimetal nickel-tin compositions have been received. Eutectic formations, arising at the surface of tin film owing to a diffusional cooperation with the nickel base have been found by the scanning electron microscopy method. The X-ray-phase analysis of tin film was performed by using the small-angle scattering.
Keywords: bimetal compositions, diffusional of interaction, eutectic, films.
Magomedov M.N.
On the variation of the baric properties with a decrease in the size of a silicon nanocrystal – page 434
Abstract: Properties of a nanocrystal are calculated by means of the Mie-Lennard-Jones pair interatomic potential and the RP-model of the nanocrystal. The state equation P(v/v0, T) and the baric dependences for the lattice and for the surface properties both for macro- and for nano-crystals of silicon are found. A changes in the properties both at isochoric (v/v0 = 1) and at isobaric (P = 0) decrease in the number of atoms in a cubic nanocrystal at the different temperatures were studied.
Keywords: nanocrystal, the state equation, isochoric, isobaric, silicon.
Magomedov R.A., Akhmedov E.N., Meilanov R.R., Beybalaev V.D., Aliverdiev A.A.
Calculations of thermophysical characteristics of xenon – page 446
Abstract: On the basis of a generalization of thermodynamics in fractional derivatives and some analytical expressions obtained, taking into account the second virial coefficient B, we calculated thermophysical characteristics of a noble gas xenon Xe: entropy S and isochoric heat capacity CV. The calculated thermophysical parameters of exemplifying on xenon at temperatures 500, 1000, 1400, 2000 К in the pressure range from 0,1 to 90 MPa are given.
Keywords: thermodynamics, fractional derivative, fractal equation of state, entropy, isochoric heat capacity.
Malyshev M.D., Baburkin P.O., Adamyan A.N., Pakhomov P.M., Komarov P.V.
Simulation of the maturation process cystein-silver solution – page 453
Abstract: In this paper, the process of maturation of an aqueous solution of L-cysteine and silver nitrate using the method of atomistic molecular dynamics is investigated. To study the maturation process, an atomistic model of the solution was developed. The study allowed to obtain new data on the structure of silver mercaptide clusters and the role of their structural features in the process of further self-organization.
Keywords: hydrogel, supramonomer, computer simulation, atomistic model.
Mikitchuk E.P., Kozadaev K.V.
Convergence for simulation of surface nanostructure optical properties using finite integral technique – page 460
Abstract: Computer model of 2D-monolayer of noble metal nanoparticles on the solid substrate in the air surrounding is improved. Convergence for simulation of surface nanostructure optical properties using finite integral technique is studied by means of electromagnetic far-field analysis as well as re-calculation of scattering matrices obtained with finite integral technique. Both simulation residual and time is estimated for named approaches.
Keywords: surface nanostructure, monolayer of metallic nanoparticles, finite integral technique, surface plasmon resonance.
Musskaya O.N., Kulak A.I., Krut’ko V.K., Glazov I.E.
Adsorption-structural properties of calcium phosphates xerogels obtained by liquid-phase synthesis – page 468
Abstract: It has been established that xerogels of basic and medium calcium phosphates obtained by dehydration of calcium phosphate gels in air at 20°C with water-removing agents, cryogenic treatment (at −18 and −196°C) are characterized by a high specific surface (up to 158 m2/g). It was found that high-temperature heating of calcium phosphates at 800−1200°C leads to a significant decrease in their adsorption capacity (ABET 10−17 m2/g).
Keywords: calcium phosphate xerogel, adsorption-structural properties, hydroxyapatite, tricalcium phosphate, brushite, carbonate hydroxyapatite.
Myasnichenko V.S., Kolosov A.Yu., Sokolov D.N., Davydenkova E.M., Sdobnyakov N.Yu.
Calculation of the surface energy of copper nanowires of different thickness and orientation – page 477
Abstract: The Monte-Carlo lattice method is used to search for the surface structure of crystalline copper nanowires of various orientations. Fragmentation of 3,3 nm thick wires into individual spherical nanoparticles is observed. When a nanowire with an initial orientation along the [100] crystallographic axis is rotated, its surface energy increases monotonically to a certain value of the angle of rotation, with a further decrease with orientation along the [110] axis. A dependence of the surface energy on the nanowire’s diameter was not revealed.
Keywords: surface, Monte Carlo method, tight-binding potential, crystal lattice, nanowire, Rayleigh-Plato instability, fragmentation.
Nagorny Y.E., Politaev D.N.
Investigation of mechanical properties of silicane in the valence force field model – page 485
Abstract: Numerical simulation of mechanical properties of silicene samples are made in the valence force field model. The dependences of elastic modules on linear dimensions are found. The results are compared with those obtained in the of central force field model. Behavior of the corresponding graphs is similar. At the same time, a lag of values of the elastic modules received within the valence force field model in comparison with the central forces field model was observed. The lag in question accrues with growth of the sample sizes.
Keywords: central force field, valence force field, silicene, Young’s modulus, Poisson’s ratio.
Nemygina N.A., Bahvalova E.S., Buchma E.V., Smirnov I.S., Nikoshvili L.Zh., Sulman E.M.
Influence of local surface plasmon resonance on behavior of polymer-stabilized bimetallic nanoparticles in Suzuki cross-coupling reaction – page 492
Abstract: This paper is devoted to investigation of the effect of light in the visible spectral range on the activity of mono- (Au, Pd) and bimetallic (Au−Pd) catalysts. Electron microscopy data showed that nanoparticles with a core-shell structure are formed during the synthesis of a bimetallic catalyst. As a result of the testing of mono- and bimetallic samples in the Suzuki reaction between 4-bromoanisole and phenylboronic acid under optimum conditions, it was found that the activity of the bimetallic catalyst increases markedly when the light response is carried out by the occurrence of a local surface plasmon resonance, which is supposed to accelerate the stage oxidative addition of 4-bromoanisole to palladium.
Keywords: Suzuki cross-coupling reaction, gold, palladium, bimetallic catalyst, hypercrosslinked polystyrene, local surface plasmon resonance.
Orakova M.M., Mustafaev G.A., Nagaplezheva R.R.
Study of wetting the surface of silicon with NaCl-water solution – page 501
Abstract: The dependence of the water runoff angles from the silicon surface on the conditions of their preparation is investigated. The objects of investigation were single-crystal silicon plates KDB-10 with orientations (111) and (100). It is shown that the use of ethanol in the preparation of plates improves wetting with water. It is also established that small doses of NaCl in water do not affect the angle of the droplet flow.
Keywords: adsorption, drain angle, wetting angle, surface tension, Auger analysis.
Pan’kin N.A., Bataykina I.A.
Investigation of the bombardment of low-energy isomers of Tin clusters (n = 7, 13, 15, 19) by titanium atoms: molecular dynamics simulation – page 506
Abstract: The process of bombardment of low-energy isomers of Tin (n = 7, 13, 15, 19) clusters by titanium atoms is considered by molecular dynamics. It is shown that the initial cluster temperature (up to 500 K) does not influence the final results. Ion bombardment leads to the destruction of the initial cluster structure with the release of smaller particles. A significant fraction of the spray/decomposition products are monomers and dimers.
Keywords: isomer, bombardment, distribution functions, cluster.
Pan’kin N.A., Mishkin Vl.P.
Electron microscopy of Cu – SiC composites: a cold-molding and solid phase sintering – page 517
Abstract: Cu − SiC composites were studied by scanning electron microscopy after processes of molding and a heat treatment. After pressing, plastic deformation of copper particles and traces of destruction of silicon carbide (cracks and debris) are observed. After the solid-phase sintering, formation of a porous structure in the matrix material is noted without significant changes in the filler particles. Data on the distribution of chemical elements near the SiC − Cu interface indicate an insignificant effect of diffusion processes.
Keywords: composite, electron microscopy, copper, silicon carbide, microstructure, pores.
Petrik G.G.
A modelling approach to the choice of the equations of state of analogues of three series – page 524
Abstract: Within the framework of a simple molecular thermodynamic model, the problems of comparing the equations of state and the choice of analogues in three sets are analyzed: equations based on the model of interacting point centers, van der Waals type equations, and Martin equations obtained on the basis of translation by volume.
Keywords: simple equations of state, cubic equation, model of interacting point centers, volume translation, control parameters, choice of optimal equations of state.
Polukhin V.A., Kurbanova E.D., Belyakova R.M., Rigmant L.K.
The effect of hydrogenation on the processes of structuring and vitrification of suppercooled melts – page 535
Abstract: There have been considered the characteristics and structure forming of amorphous and nanocrystalline binary and ternary alloys based on Pd, as well as high-entropy Zr − Cu (Ni, Ti) compositions based on binary Ni − Ti, Ni − V and ternary Zr − Cu − Ti systems, which are difficult to manufacture, however, can significantly improve the economic efficiency of the processes of separation, purification of hydrogen and its safe storage. The analysis of the formation specificities of stable functional structures of membrane amorphous and nanocrystalline alloys in depending on their ability to hydride formation was also carried out.
Keywords: molecular dynamics, metallic glasses, vitrification, nanocrystalline alloys, transition metals, hydrogenation, clusters, short-range ordering, medium and long-range order.
Redel L.V., Gafner Yu.Ya., Gafner S.L.
Structural stability of small FCC – magic silver clusters for plasmonic applications – page 542
Abstract: One of the new applications of silver nanoparticles is their use in plasmon applications, which are determined by the strong interaction between the electromagnetic wave and free electrons in nanostructures. Particles of a metal with a size smaller than the wavelengths of visible light can strongly absorb light due to the phenomenon of surface plasmon resonance, due to the collective oscillation of conduction electrons. The frequency and intensity of the plasmon resonance depends on the distribution of the polarization charge in the nanostructure, which, in turn, is determined by the shape and structure of the nanoparticle. Thus, control of the structure of the metallic nanostructure allows you to control the wavelengths of light that it dissipates and absorbs.
Keywords: nanoclusters, silver, structure, computer simulation, tight-binding.
Savenko V.I., Samkanashvili D.G.
Nanoscale diagnostics of the «chicken wire» structure on the electron image of microchannel plates exposed to photoelectron scrubbing – page 550
Abstract: This paper presents the results of investigation of experimental prototypes of microchannel plates after photoelectron scrubbing. In the case of photoelectron scrubbing microchannel plate parameters are influenced mainly by the electron processing. The UV light influence on microchannel plate performance is insignificant when there is no voltage supply. Nano-scale contamination which exists in small amounts at some multi-boundaries is cleaned off when exposed to the input current.
Keywords: microchannel plate, photoelectron scrubbing, UV radiation.
Savenko V.I.
Effect of electronic irradiation on properties, composition of lead-silicate glasses and coefficient of secondary electron emission on their surface – page 557
Abstract: The paper discusses the effectiveness of methods for degassing surfaces of lead-silicate glasses by electron irradiation (treatment) in order to increase the efficiency of secondary electron emission. Changes in the properties and composition of the processed materials as a result of additional effects (heat treatment, reactions with ethyl alcohol, etc.) are revealed. Chemical compounds and elements formed as a result of impacts on the surface of lead-silicate glasses are described. The effect of sample storage on a further change in the secondary electron emission coefficient was studied.
Keywords: electron irradiation, electron processing, lead-silicate glass, processed surface of lead-silicate glasses, secondary electron emission, amplification.
Sverdlik G.I., Ataeva A.Y., Kambolov D.A., Ataev A.R.
Classification and selection of barbage equipment for collecting dust nanoparticles – page 566
Abstract: А classification of bubblers according to a constructive feature has been developed on the basis of literature analysis and patent search. A comparison of different types of bubblers has been performed according their ability to effectively capture small particles, including nanoparticles. For this purpose it is recommended to use a jet bubbler developed in the North Caucasian Institute of Mining and Metallurgy (State Technological University) on the basis of the patented distribution cup cap plate.
Keywords: gas emissions, nanoparticles, bubbler classification, jet bubbler, foam regime, experimental installation.
Sdobnyakov N.Yu., Samsonov V.M., Bazulev A.N.
Size of metal nanoparticles as a factor of their stability – page 576
Abstract: Using available experimental data on evaporation rates for metal nanoparticles and shrinkage rates for vacancy pores, evaluations have been performed of the particle size ranges where the linear dependence σ = Kr between the surface tension σ and the particle radius r. The reliability intervals have been found for the proportionality coefficient K. The results obtained are compared to evaluations by E.N. Vitol (1992). On the bases of the results of these evaluations a conclusion has been confirmed that a thermodynamic stability condition obtained before is fulfilled for nanoparticles of all metals considered in the paper.
Keywords: metal nanoparticles, Rusanov’s formula, stability, evaporation of nanoparticles, shrinkage of vacancy pores.
Sidorov N.V., Shuvalova A.M., Teplyakova N.A., Palatnikov M.N.
Particularities of the structure and photoelectric fields of LiNbO3 : Zn crystals – page 584
Abstract: Values of intensities of photovoltaic and diffusion fields were determined in congruent LiNbO3 crystals both nominally pure and doped by zinc due to parameters of a photoinduced light scattering. A change in electro-optical properties of LiNbO3 : Zn crystals at an increase in the zinc concentration to a threshold value was shown to be determined by particularities of oxygen octahedra deformations and an order of cation sublattice structure units along the polar axis.
Keywords: single crystal, lithium niobate, doping, photoinduced light scattering, photorefractive effect, photovoltaic field, diffusion field.
Simakov V.V., Sinev I.V., Osyko I.D., Shcherbakova E.A., Grebennikov A.I.
I-V characteristics of gas sensors based on tin dioxide thin films in wet air at room temperature – page 591
Abstract: In this work cyclical I−V characteristics of a gas sensor based on tin dioxide thin films in wet air at room temperature has been studied. It was demonstrated that cyclical voltage variation leads to redox reactions on the surface of the gas sensor active layer. Redox reaction potential does not depend on the gas concentration in an analyzed gas probe. Therefore, the redox potential can be used as an identifying agent.
Keywords: I−V characteristics, gas sensors, thin films, tin dioxide, room temperature, gas mixture identification.
Skachkov V.М., Pasechnik L.А., Skachkova О.V., Yatsenko S.P.
Diffuzionno-hardening solders based alloy gallium-indium-tin and powder of metal PCTSP5 reinforced with titanium – page 600
Abstract: The paper considers a new composition of diffusion-hardening solder based on a low-melting gallium alloy and copper-tin spherical powder (PCTSP5). The influence of the powder filler – titanium composition on the structure and properties of solder for expanding the areas of use is investigated. Strength properties, microstructure, thermal stability of the samples were studied.
Keywords: metal powder, composite diffusion-hardening alloys, solders, structure, properties, microhardness, differential thermal analysis.
Starodub O.R., Voskresenskij V.M., Sidorov N.V., Palatnikov M.N.
Mathematical simulation of cluster formation in lithium niobate crystals with introduction of the impurity ion – page 609
Abstract: Processes of clustering in a lithium niobate crystal (LiNbO3) were studied. It is shown that the cluster with the ratio Li / Nb ≈ 0,945, which is close to the ratio of lithium to niobium in a congruent crystal, is the most energy-efficient cluster. It was found that because of the loss of electroneutrality, a cluster of stoichiometric composition can not exist. It is established that there is an optimal relationship between the energy of the cluster, its size and the Li / Nb ratio.
Keywords: lithium niobate, modeling, clusters, vacancy models, sublattice defects, single crystals, ferroelectrics.
Talyzin I.V., Samsonov M.V., Vasilyev S.A., Pushkar M.Yu., Dronnikov V.V., Samsonov V.M.
Molecular dynamics research of size dependence of the melting temperature of silicon nanoparticles – page 618
Abstract: Size dependence of the melting temperature of Si nanoparticles has been investigated combining molecular dynamics and thermodynamic simulations. The results of the atomistic simulation obtained using the Stillinger-Weber potential agree with the results of other authors and with the thermodynamic simulation results based on Thomson’s formula. These results predict that the melting temperature Tm of Si nanoparticles diminishes with increasing their reciprocal radius R-1 following to the linear law. The available experimental data predict much lower values of Tm, including underestimated values of the limiting value Tm(∞) found by means of the linear extrapolation of experimental dots to R-1 → 0 (i.e. to the particle radius R → ∞), and the underestimation of Tm(∞) ranges from 200 to 300 K in comparison with the melting point 1688 K of the bulk crystalline Si. Taking into account the obtained results and their comparison with available results of other authors, a conclusion is made that molecular dynamics results, obtained by using the Stillinger-Weber potential, should be more adequate than the available experimental data on the melting temperature of Si nanoparticles.
Keywords: silicon nanoparticles, melting temperature, size dependence, molecular dynamics, thermodtynamics.
Teplyakova N.A., Sidorov N.V., Palatnikov M.N.
Defective structure and photorefractive properties of double doped crystals LiNbO3 : Fe : Mg and LiNbO3 : Fe : Zn – page 628
Abstract: A comparative analysis of photorefractive properties was carried out for congruent, stoichiometric and double doped lithium niobate crystals: LiNbO3 : Fe(0,009) : Mg(5,04) and LiNbO3 : Fe(0,02) : Zn(4,34) mol %. These crystals are different in defect types, which are responsible for the effect of photorefraction. Band gap was shown to be minimal for double-doped crystals, photorefractive effect to be the same as for stoichiometric crystals, and photoinduced light scattering was not observed.
Keywords: single crystal, lithium niobate, doping, photoinduced light scattering, photorefractive effect, band gap.
Uglev N.P., Zamorin I.N., Uglev S.N., Smirnov S.A., Selivanov A.M.
Distribution of components of jewelry alloy in the bulk of metal castings – page 636
Abstract: The process is investigated of stratification of a quaternary jewelry alloy within the height of a vertical metal crucible. The concentration distribution of the alloy components near the surface of castings, as well as the features of the structure formation of the solid alloy is studied. It is shown that the distribution of metals in the volume generally corresponds to known data for other metallic melts. A direct correlation of the microhardness to the alloy composition is revealed.
Keywords: multicomponent metal melt, stratification, distribution of components, microhardness, long-range order, swarm of clusters, superfluidity.
Khubolov B.M., Podlinov V.P., Bagov A.M.
Study of materials for electrochromic devices: physical and chemical methods – page 646
Abstract: The methods of producing and investigation of electro-chromically-sensitive thin films of tungsten oxide bronzes have been considered in peer-review. The researches allowing one to make deductions on the particular models of the physical process laying in the basis of the electrochrome effect have been described in detail. The most important problems of the further studies on the complex oxides of the transition metals for obtaining applied results capable to start the highly effective technology of the electrochrome devises have been formulated.
Keywords: electrochromism, oxide potassium-tungsten bronze, thin films, spectral characteristics, single crystals, electrovacuum deposition, technological parameters of deposition.
Khubolov B.M., Podlinov V.P., Bagov A.M.
Optical characteristics of thin films of potassium-tungsten bronzes – page 656
Abstract: The spectral dependences of the optical density of thin amorphous film of oxide potassium-tungsten bronze of hexagonal structure and composition K0,3WO3 have been measured. The central problems of interpreting of optical spectra of oxide tungsten bronzes have been postulated.
Keywords: tungsten-potassium oxide bronze, thin films, spectral characteristics, discrete evaporation, absorption centers.
Shepelevich V.G.
Grain structure of bismuth-tin alloys, additional doping with indium – page 665
Abstract: Results of investigation of the grain structure of bismuth-tin additionally doped with indium are presented. The foils have microcrystalline structure. Average sizes of bismuth ones were less than 2 μm and of tin ones were of 3 μm. The bright (10 1 2) textures of bismuth and (100) of tin are formed in the foils.
Keywords: high speed crystallization, foil, grain, grain boundary specific surface, tin, bismuth, indium.
Shermetov A.Kh., Shokarov A.A., Ponezhev M.Kh., Sozaev A.V., Karamurzov B.S.
Wetting of aluminum and copper substrates by lead – nickel melt – page 671
Abstract: In this paper, the task of obtaining new solders for brazing nickel and its alloys. Polyterms of wetting angle for Pb − Ni melts in the range from the melting point to 940 K on copper substrates and up to 900 K on aluminum were studied and wetting thresholds were detected: wetting of copper substrates starts at 640 K, and aluminum substrates are not wetted by the abovemelts.
Keywords: wetting angle, aluminum, nickel, copper, temperature of wetting threshold.
Shomakhov Z.V., Shomakhova R.A., Molokanov O.A., Karmokov A.M.
Diffusion of potassium ions and electrical conductivity in glass for electronic optics – page 677
Abstract: The results of a study of the electrical conductivity and diffusion of potassium ions in borate-barium glass (C78–5) – 2,2% SiO2 57,8% B2O3 8,2% K2O 19,0% BaO 3,5% CaO 8,8% Al2O3 0,5% MgO with the passage of electric current through the sample. The time dependences of self-diffusion coefficients are calculated for the transmission of an electric current at a constant temperature.
Keywords: electrical conductivity, ion diffusion, borate-barium glass, isothermal annealing.
Shcherbakova V.B., Sadovskaya L.Yu., Logvinovich A.S., Sviridova Т.V., Sviridov D.V.
Photo-accumulating composite materials based on heteropolymolybdates – page 683
Abstract: It was shown that modifying titanium dioxide particles with ammonium 6-molybdoferrate (II) and ammonium 6-molybdonickelate (II) gives the photocatalyst the ability to accumulate a photogenerated charge and maintain oxidative activity for some time after ultraviolet irradiation. In this case, heteropolymolybdates not only ensure the accumulation of a photoinduced cathodic charge, but also the conversion of hydrogen peroxide, formed during the oxidation of reduced forms of heteropolymolybdates with air oxygen, to highly active hydroxyl radicals.
Keywords: nanodispersed titanium dioxide, photochemistry, polycondensation of oxoacids of transition metals, ultraviolet radiation, heteropolymolybdates.
Yurov V.M., Guchenko S.A., Laurinas V.Ch.
Thickness of the surface layer, surface energy and atomic volume of the element – page 691
Abstract: The thickness of the surface layer of an atomically pure metal, which turned out to be equal to 5-6 nm, was calculated in this work. It is shown that the thickness of the surface layer is determined by one parameter – the atomic volume of a chemical element. A simple relationship between the surface energy of a metal and its melting point is obtained. All the relationships obtained are in good agreement with the experimental data.
Keywords: surface layer, nanostructure, surface energy, atomic volume, size effect.
Simulation of interaction process in the system STM probe – sample with a complex relief: recommendations on the standard technological mode – page 6
A.S. Antonov, D.N. Sokolov, N.Yu. Sdobnyakov, A.Yu. Kolosov, V.S. Myasnichenko, V.I. Romanovskiy
Abstract: Using the Gupta many body potential and the Monte Carlo method, simulation of interaction in the probe (copper) – sample (gold) system with thermal expansion, depending on the distance between them has been carried out for two types of relief: «wave» type and «grain» type. It is established that the thermal expansion of the tip of the probe can reach values comparable to the width of the tunnel gap, and possibly the occurrence of an avalanche process of thermal expansion of the tip, leading to the formation of a contact between the tip of the probe and the surface of the sample. The recommendations on the standard technological mode of the scanning tunneling microscope have been formulated.
Keywords: Monte-Carlo method, Gupta potential, scanning tunneling microscopy, probe-sample contact.
Research of morphology of the relief of copper films on the mica surface – page 19
A.S. Antonov, N.Yu. Sdobnyakov, D.V. Ivanov, K.B. Podbolotov
Abstract: A scanning tunneling microscope has examined morphology of the relief of copper films obtained by thermal vacuum deposition on the surface of mica. The characteristic features of the nanorelief of the film surface, including fractal properties, are described.
Keywords: scanning tunneling microscopy, nanorelief, fractal dimension, copper films.
Influence of polarization of metallic ions of a transition layer on the metal – nonpolar organic liquid boundary on the interfacial energy – page 27
A.M. Apekov, I.G. Shebzukhova
Abstract: Within the frames of a modified version of the electronic statistical theory, an amendment to the interfacial energy at the metal-nonpolar organic liquid interface on the polarization of metal ions of the transition layer in the field of a semi-infinite metal is obtained. An effect of the correction on the macroscopic dielectric permeability of the liquid and orientation of the metallic crystal is established.
Keywords: polarization correction, interfacial energy, electron-statistical method, alkali metals, nonpolar organic liquid.
Surface energy of thin films of tantalum and niobium with the monoaxies deformation – page 32
L.P. Aref`eva, I.G. Shebzukhova
Abstract: Dependence of the surface energy of metal thin films on the monoaxies deformation of compression and stretching has been qualitatively described. Calculations made for films of tantalum and niobium by modified electron-statistical method. The influence of deformation on the electron density of the system and the Gibbs coordinate has been demonstrated. A weak nonlinear change of the surface energy with the monoaxies deformation has been determined.
Keywords: surface energy, thin films, monoaxies deformation, tantalum, niobium, modified electron-statistical method.
Interfacial energy of uranium-metal melt boundary – page 38
L.P. Aref`eva, I.G. Shebzukhova
Abstract: The interfacial energy of uranium boundary with alkali and alkaline-earth metals has been estimated by the electron-statistical method. It has been shown that alkali and alkaline-earth metals are strong surfactants relative to uranium. Formulas for polarization correction, external and temperature terms, have been obtained which take into account change of density at the contact boundary. The temperature contribution in the interfacial energy of crystal faces of three allotropic modification of uranium has been estimated. The influence of s-metal melts on the profile of electron density has been analysed.
Keywords: interfacial energy, uranium, alkali metals, alkaline-earth metals, melt, actinides, allotropic phases.
Diffusional interaction and phase formation in nickel–aluminum films – page 45
S.N. Akhkubekova, V.K. Kumykov, M.Z. Laipanov, A.R. Manukyants, V.A. Sozaev, B.M. Khubolov
Abstract: In the present paper bimetal nickel –aluminum films are obtained in vacuum by method of the contact melting at temperature 650°C. The eutectic formations which appear on the surfaces of the films due to diffusion are detected by method of the raster-type electron microscopy.
Keywords: Contact melting, intermetallics, phase formation, eutectic.
Calculation of the state equation and the isobaric size dependencies of molybdenum nanocrystal – page 49
E.N. Akhmedov
Abstract: On the basis of the RP-model the equation of state of the bcc-molybdenum nanocrystal has been calculated that accounts its size and shape. It is shown that the isobaric size dependencies of the Debye temperature and the first Grüneisen parameter increase with increasing temperature. The surface energy isotherms for macrocrystal and nanocrystal intersect. In a particular area the surface energy of nanocrystal becomes higher than that of macrocrystal.
Keywords: equation of state, nanocrystal, molybdenum, size, shape.
Study of the distribution of somonomers in virtually synthesized block-pvkl-pvkl-pvi-copolymers – page 57
P.O. Baburkin, A.V. Lebedev, P.V. Komarov
Abstract: In this publication the results are presented of an analysis of statistical properties of the distribution of monomer units in copolymer chains synthesized in silico based on vinylcaprolactam and vinylimidazole. Such polymer chains demonstrate one of the basic properties of protein molecules, and exactly, they are able under conditions of a «bad» solvent (for vinylcaprolactam blocks) to take a dense globular structure with a hydrophobic core surrounded by a hydrophilic «corona». Despite the external similarity of the morphology of globules with protein-like copolymers, the distribution of comonomers attached to the first hydrophobic block has a random character.
Keywords: Coarse-grained computer simulation, amphiphilic copolymers, protein-like polymers, enzyme.
Modeling of CuAu nanoparticle formation during the gas phase synthesis – page 64
V.S. Baidyshev, V.А. Tsura, I.V. Chepkasov
Abstract: In this work computer simulation of the cluster condensation from a high-temperature gas phase containing pairs of copper and gold atoms was carried out by the molecular dynamics method. The average growth rates of clusters and the stoichiometric composition of the emerging particles are determined. It is shown that for particles with diameter of 3 nm or more the molar composition tends to Cu0,75Au0,25.
Keywords: computer simulation, molecular dynamics, condensation, CuAu nanoalloy.
The structure of body after manufacturing selective laser melting of iron powder – page 71
B.K. Barakhtin, A.S. Zhukov, M.V. Staritsin, N.A. Vershinina
Abstract: The structure investigation results of selective laser melting (SLM) samples of iron powders are presented. The size of a volume was determined, where crystallographic face germs have been formed via condensation from metals vapors. Nanofaces formed during the crystallization contribute to the SLM material stability.
Keywords: selective laser melting, metal powder, nanophase.
Molecular dynamics and thermodynamic simulations of segregation phenomena in binary Au-Ag nanoparticles – page 81
A.G. Bembel
Abstract: A complex approach combining atomistic molecular dynamics (MD) and thermodynamic simulations was applied to predict segregation in binary Au-Ag nanoparticles consisting of 2000 atoms (of about 4 nm in size). Both approaches predict the surface segregation of Ag to the surface of Au-Ag nanoalloys. Besides, Au-Ag nanoparticles demonstrated an onion like structure with an outer Ag monolayer. The results of MD and thermodynamic simulations agree with the available experimental data.
Keywords: Au-Ag nanoparticles, surface segregation, molecular dynamics, thermodynamic simulation.
Field desorption of sesium atoms from nanostructured rhenium surface – page 89
D.P. Bernatskii, V.G. Pavlov
Abstract: Using method of the field desorption microscopy, desorption of cesium atoms from quasi-spherical surface of a rhenium microcrystal in the electric field has been investigated. The dependence of the desorbing electric field strength vs cesium coverage of the surface has been obtained. In the framework of the image force model for the field desorption, the heat of adsorption of cesium atoms in dependence on the surface concentration of cesium and the work function of the surface has been evaluated.
Keywords: field desorption microscopy, ion sources, field emitter, rhenium, alkaline metals.
The effect of calcium-containing reagents on Bayer leaching of bauxites – page 94
S.А. Bibanaeva, N.А. Sabirzyanov, V.N. Koryukov
Abstract: The results of the experimental study of the effect of calcium-containing reagents on the degree of leaching of Timanian deposit bauxites by a parallel method of Bayer sintering are presented. The phase composition of the interaction products is determined by the XPA and EDAX methods. The formation of calcium hydoxysilicate in red mud is found.
Keywords: alumina production, leaching, calcium oxide, calcium hydrosilicate.
The influence of fluoride ions on the strength properties of hydroxyapatite and based on it composite materials – page 99
E.A. Bogdanova, O.V. Skachkova, V.M. Skachkov, N.A. Sabirzyanov
Abstract: The article discusses the possibility of hardening of stoichiometric hydroxyapatite (HAP) obtained by deposition from a solution by means of the partial substitution of hydroxyl groups with fluorine ions and the introduction of reinforcement additive (10, 15, 20 wt.% CaF2). The peculiarities of chemical interaction of HAP with the reinforcement additive during thermal treatment have been revealed. The effect of the phase composition on the strength characteristics of investigated samples has been shown.
Keywords: hydroxyapatite, fluorine-substituted hydroxyapatite, composite biomaterials, microhardness.
Instrumental and methodological support of the non-standard researches of the magnetic nanodispersed oils – page 108
A.N. Bolotov, V.V. Novikov, O.O. Novikova
Abstract: In the present work we submit an equipment and research technique to study corrosive and tribotechnical properties of the nanodispersed media. The proposed equipment allows to examine the processes which are taking place at friction contact of magnetic oils and solid surface as well as to predict the working capacity of the real tribounits with innovative nanodispersed oils.
Keywords: nanodispersed magnetic media, magnetic liquids, corrosive properties of the magnetic, friction of magnetic oils.
Thermally induced switching in PIN-PMN-PT single crystals – page 114
N.N. Bolshakova, V.V. Ivanov, A.I. Ivanova, E.M. Semenova, A.D. Senkovskiy, A.S. Smirnov
Abstract: The results of investigation of thermally induced switching in PIN-PMN-PT single-crystal solid solutions are presented. It was found that samples have the stable unipolarity. The intensity of thermally induced crystal switching processes depends significantly on the direction of the polarizing field or the electric field applied to samples.
Keywords: Barkhausen thermal effect, switching processes, PIN-PMN-PT.
Molecular dynamic study of size dependences of melting and crystallization temperatures of platinum nanoclusters – page 121
S.A. Vasilyev, A.A. Romanov
Abstract: The melting and crystallization temperatures of platinum nanoclusters have been found by using results of molecular dynamics modeling, obtained employing two different computer programs and different interatomic interaction potentials. The size dependences found in computer experiments are compared with molecular dynamics data of other authors and with estimations of the melting temperature using Thomson’s formula.
Keywords: nanoclusters of platinum; molecular dynamics; tight-binding potential, embedded atom method, melting temperature, crystallization temperature.
Magnetooptical control of spatial magnetic field distribution in microelectromechanical systems – page 128
M.K. Virchenko, R.M. Eguzhokova, A.B. Zaletov, A.I. Ivanova
Abstract: A study is performed of the spatial distribution of magnetic field of a microelectromechanical systems (MEMS) with the aid of magneto-optical indicator ferrite garnet films (MOIF). In order to increase the accuracy and the dynamic range of measure a procedure was developed including the use of auxiliary external field resulting in a controlled shift of the zero-field lines. In this case the MOIF serves as a null-indicator eliminating the dependence of the measuring results on the specific transfer parameters (linearity characteristics). Imposition of biasing field provides a possibility of shifting the saturation threshold field of the MOIF either in the region of positive or negative values.
Keywords: magnetic measurements, magneto-optical effects, indicator films, microelectromechanical systems (MEMS), dynamic range of measurement.
Study of the possibility of diamond formation at moderate pressures and temperatures – page 133
S.А. Voropaev, N.V. Dushenko, A.S. Aronin, V.M. Shkinev, E.M. Galimov
Abstract: Data on the diamond synthesis in experiments with carbon-saturated metal melts at moderate pressures and temperatures are presented. Features of the resulting diamond phase, the types and nature of inclusions are discussed and compared with those for natural microdiamonds found at the volcanic rocks of Kamchatka.
Keywords: diamond, impurity, inclusions, volcanic, rock, catalysts.
Computer simulation of structure and dimensions of oxygen-octaadric clusters in lithium niobate crystal and the dynamics of their development with changes in composition – page 140
V.M. Voskresensky, O.R. Starodub, N.V. Sidorov, M.N. Palatnikov
Abstract: The peculiarities of formation of energetically equilibrium dipole oxygen-octahedral clusters in the structure of a ferroelectric crystal of lithium niobate (LiNbO3) have been studied by computer simulation. It is shown that there is an optimal relationship between the cluster energy, its size, and the Li / Nb ratio.
Keywords: lithium niobate, modeling, clusters, vacancy models, defects of sublattice.
Physico-chemical aspects of electrotransport of keplerate-type nanocluster polyoxoanions in native membranes – page 147
I.D. Gagarin, N.A. Kulesh, M.O. Tonkushina, D.A. Vlasov, A.A. Ostroushko
Abstract: Optimal mode of percutaneous electrotransport of keplerate-type nanocluster polyoxometallate in vitro experiments is chosen. A research method is developed, new experimental data on the layer-by-layer distribution of iron-molybdenum polyoxometallate in the skin are obtained using the X-ray fluorescent spectroscopy.
Keywords: nanocluster polyoxoanions, native membranes, percutaneous electrotransport, concentration-depth distribution.
Modelling of the L12 → FCC phase transition in Cu3Au nanoclusters – page 153
Yu.Ya. Gafner, S.L. Gafner, L.V. Redel, I.S. Zamulin
Abstract: Boundaries of thermal stability of the initial L12 phase in clusters of Cu3Au nano-alloy of up to 8 nm in size were investigated by molecular dynamics method using a modified tight-binding potential TB-SMA. It is shown that under the influence of the temperature factor FCC structure in Cu3Au clusters is possible i.e. a structural transition L12 → FCC. It is concluded that, unlike macroscopic bodies this transition in nanoparticles occupies a wide temperature range.
Keywords: nanoalloy, structure, computer simulation, tight-binding potential.
Photo-catalysts on the basis of quasi-unidimensional state of cobalt and copper activated – page 160
O.I. Gyrdasova1, I.V. Baklanova1, E.V. Shalaeva1, M.A. Melkozerova1, L.Yu. Buldakova1, N.S. Sycheva1,2
Abstract: Zn1-xMxO (0 ≤ x ≤ 0,1) solid solutions with tubular morphology of aggregates and Zn1-xMxO1-yCy : nMO (0,1 ≤ x ≤ 0,3) composites were obtained using formate-glycolate complexes Zn1-xMx(HCOO)(OCH2CH2O)1/2 (M = Co, Cu; 0 ≤ x ≤ 0,3). The materials are tested in the oxidation of 1,4-dihydroxybenzene under the action of visible radiation. It is established that copper in Zn1-xMxO (0 ≤ x ≤ 0,1) is more effective than cobalt. Its presence in composites leads to a decrease of the photocatalytic activity.
Keywords: Zinc oxide, nanostructures, synthesis, precursors, morphology, microstructure, defects of structure, dynamics of electron excitations, photocatalysts.
Magnetic properties of sintered heterogeneous compositions based on alloys of 3d- and 4f- transition metals – page 169
O.B. Dyogteva, Е.М. Semenova, М.B. Lyakhova, Yu.V. Kuznetsova
Abstract: The paper presents the results of investigation of the magnetization reversal processes of sintered powder compositions based on micropowders of Nd2Fe14B and Sm(Co0,6Cu0,4)6,0 alloys. Samples were obtained in a high-coercivity state. It is shown that an increase in the volume content of Nd2Fe14B in the composition of the samples under study leads to an increase in the saturation magnetization and to a significant decrease in the coercive force.
Keywords: magnetic properties, heterogeneous state, rare earth intermetallics, coercivity.
Temperature dependence of angles of wetting of porous nickel by Pb-0,49 atomic percent % Na melt – page 177
K.M. Elekoeva, Y.N. Kasumov, A.R. Manukyants, M.Kh. Ponegev, V.A. Sozaev, A.Kh. Shermetov
Abstract: Polyterms of angles of wetting of porous nickel and nickel of brand НП-2 by atomic percent melt are investigated. Thresholds of wetting, which are bound with oxides on the surface of drops and nickel are detected. It is found, that temperature at which the threshold of wetting at porous nickel is observed by ° below than at nickel of brand НП-2.
Keywords: wetting, temperature dependence, porous nickel.
Formation of fases at the boundary of the double-layer copper-aluminium film – page 182
K.M. Elekoeva, P.K. Korotkov, M.Z. Laipanov, A.R. Manukyants, V.A. Sozaev, B.M. Khubolov
Abstract: Outcomes of formation of phases are reduced at the contact melting of recordings of aluminium with copper. With the help of a raster electronic, atomic – force microscopy and X-ray analysis the eutecticum and intermetallic AlCu4 phases are detected.
Keywords: phase forming, contact melting, intermetallides.
Local environment of cations in double shellites Li(Na)Bi(MoO4)2 by NMR data and quantum-chemical calculations – page 189
N.A. Zhuravlev, D.V. Suetin, I.R. Shein, A.V. Skachkov, A.A. Savina, T.S. Spiridonova, A.L. Buzlukov, T.A. Denisova
Abstract: The electronic structure was calculated by the first-principle methods of quantum chemistry and the parameters of the electric field gradient near the 7Li nuclei of the double molybdate LiBi(MoO4)2 were determined. Analysis of the NMR spectra revealed that the states of the 7Li nuclei in LiBi(MoO4)2 in the cation sublattice do not differ, whereas in the NaBi(MoO4)2, the Na atoms in Bi positions have different populations and electric field characteristics.
Keywords: LiBi(MoO4)2, NaBi(MoO4)2, scheelite structure, electronic structure, quantum chemical calculations, NMR 7Li , 23Na , parameters of EFG.
Properties evaluation of mesoporous silica nanopowders doped with manganese dioxide produced by a pulsed electron beam evaporation for biomedical applications – page 199
O.A. Zlygosteva, S.Yu. Sokovnin, V.G. Il’ves
Abstract: The researched manganese-doped mesoporous silica nanopowder (NP) SiO2 – MnO2 with different dopant concentrations has been carried out by a physical method of the electron beam evaporation in vacuum on NANOBIM-2 installation. Basic analyses of NP demonstrate high porosity and ferromagnetic properties. Cytotoxicity experiments on cells showed that NP exerted low toxicity. The loading experiments using a spectrophotometer demonstrate interaction of the Amoxicillin drug with the surface of NP.
Keywords: mesoporous silica nanopowders doped with manganese dioxide, active targeted drug delivery.
Electrostriction mechanism of light induced lens response in nanosuspension – page 205
V.I. Ivanov, A.V. Myagotin, G.D. Ivanova
Abstract: A theoretical analysis of the light induced mass transfer in a dispersive liquid is carried out for large intensities of radiation in the field of Gaussian beam. The non-linear lens exponentially increases with the intensity of light, when the change in concentration is greater or comparable to the primary value. It is shown that the light induced response is limited by the Raleigh scattering for the case of high concentrations of nanoparticles.
Keywords: self-action radiation, electrostriction, nanosuspension.
Influence of the surface nanotopography on the electrical resistance of a discrete contact of solids – page 210
V.V. Izmailov, M.V. Novoselova
Abstract: An influence of micro- and nanoscale deviations of real surfaces of engineering devices from ideal form on the electrical resistance of a discrete contact of solids has been considered. It is shown that the influence of the nanoroughness on the value of the contact electrical resistance is minor both in contact of nominally flat surfaces and in local contact of a ball and the plane.
Keywords: surface, microroughness, nanoroughness, contact, contact electrical resistance.
Properties of mesoporous amorphous-nanocrystalline Gd2O3 – SiO2 powders prepared by pulsed electron beam evaporation – page 217
V.G. Ilves, S.Yu. Sokovnin, A.M. Murzakayev, T.M. Demina
Abstract: Mesoporous amorphous-nanocrystalline powders Gd2O3 – SiO2 (the specific surface area up to 177 m2/g, particle size less than 10 nm and large pore volume up to 1,19 cm3/g) were obtained by pulsed electron beam evaporation. Porous Gd2O3 – SiO2 nanoparticles are promising as nanocontainers for the drug delivery to cancer cells and contrast agents for the magnetic resonance imaging. Besides, they can used in catalysis and in other fields of nanotechnology.
Keywords: pulsed electron beam, mesoporous amorphous-nanocrystalline powders Gd2O3 – SiO2.
Experimental and theoretical substantiations of stepwise mechanism of crystal formation from liquid phase – page 223
B.I. Kidyarov, A.S. Stoporev, A.Yu. Manakov
Abstract: This article reviews studies of the sequence of phase transitions of the «liquid – solid» and «solid – solid» type, including formation of intermediate phases (Ostwald’s rule of stages). It is emphasized that such transformations also take place in a nanoscale state with the formation of nano-nuclei of high-pressure phases. Experimental data on the kinetics of the nanoscale stage of gas hydrates nucleation in water-in-oil emulsions, pointing to the stepwise mechanism of the process, are discussed for the first time.
Keywords: nano-nuclei, phase transitions of the «liquid – solid» and «solid – solid» type, Ostwald’s rule of stages.
Temperature and concentration dependence of effective potentials of Na+ and Cl– ions in aqueous solution – page 230
A.P. Klinov, E.A. Zubova, M.A. Mazo
Abstract: We have derived effective potentials of Na+ and Cl– ions in implicit water at temperatures from 273 to 340 K and concentrations between 0,3 and 1 M. We divide the potentials into two parts: slowly decreasing Coulomb function and solvation energy. The primary dependence of the effective potentials on the parameters proved to be in the dependence on them of the dielectric constant. Slight temperature dependence of the solvation is present for the pairs Na+ – Na+ and Na+ – Cl– only.
Keywords: effective ion potentials, coarse-grained model, temperature dependence, concentration dependence.
Formation of MAX-phases by electronically-ion-plasma methods – page 236
A.A. Klopotov, Yu.F. Ivanov, A.D. Teresov, E.S. Marchenko, V.D. Klopotov
Abstract: The results of structural studies of the formation of MAX-phases on the surface of titanium alloys synthesized as a result of combined treatment combining the electric explosive alloying and irradiation with a high-intensity pulsed electron beam are presented.
Keywords: MAX–phase, state diagram, triple layered compounds, electric explosive alloying, high-intensity pulsed electron beam.
Effect of charge transfer in semiconductor films NaAuy on its emission properties – page 245
M.V. Knatko, M.N. Lapushkin
Abstract: The dependence of the current of sodium ions in an external electric field from the surface of gold coated with a NaAuy film on time of its exposure in electric field of high intensity was studied. A model is proposed that relates kinetics of the ion current recovery after a change in the electric field intensity with the redistribution of positive and negative charges in the bulk NaAuy under the action of an external electric charge.
Keywords: adsorption, alkali metals, gold, intermetallic, thermal desorption of atoms and ions, surface ionization.
The investigation of the influence of point defects on the thermodynamic and structural properties of nanocompacted cobalt and copper – page 252
A.Yu. Kolosov, D.N. Sokolov, V.S. Myasnichenko, N.Yu. Sdobnyakov, P.M. Ershov, A.A. Khort
Abstract: To study the effect of volume and surface defects on the thermodynamic and structural characteristics of nanoclusters of cobalt and copper, the Monte Carlo method was applied. The interaction between atoms was described by the many-body Gupta potential. It is determined that in simulation of thermal exposed metallic nanoparticles with point defects there are insignificant deviations of their structural characteristics from values corresponding to non-defect nanoparticles.
Keywords: metal nanoparticles, Monte Carlo method, Gupta potential, volume and surface defects.
The internal rotation in 1,1,1-trifluorinealkanes – page 258
A.V. Kotomkin, N.P. Rusakova, V.V. Turovtsev, Yu.D. Orlov
Abstract: 14 potential functions V(φ) of the internal rotations around the C – C bonds in molecules of 1,1,1-trifluorine alkanes CF3 – (CH2)n – CH3, where 1 ≤ n ≤ 4, were obtained and approximated by Fourier series. The local minima of V(φ) and transition states (TS) have been studied for all examined compounds. A comparison of the rotation characteristics of studied molecules those of same in n-alkanes and 1-monofluorine alkanes was performed. The transferability of rotation parameters around C – C bonds has been showed.
Keywords: 1,1,1-trifluorine alkanes, potential function, conformational analysis, internal rotation.
Influence of tricalcium phosphate phase on the strength of hydroxyapatite foam ceramics in the thermal annealing process – page 264
V.K. Krut’ko, A.I. Kulak, O.N. Musskaya, T.V. Safronova
Abstract: The presence of the tricalcium phosphate phase in hydroxyapatite foam ceramics after annealing at 1200°C during 3 h leads to a certain decrease in porosity from 45% to 27 – 38%, to an increase in the degree of resorption and to a significant decrease in the static strength from 3 – 7 to 0,2 – 0,4 MPa.
Keywords: hydroxyapatite foam ceramics, tricalcium phosphate, polyurethane foam, polyvinyl alcohol.
Electron-stimulated desorption of lithium atoms from oxidized tungsten – page 271
Yu.A. Kuznetsov, M.N. Lapushkin
Abstract: We have studied the processes of electron-stimulated desorption (ESD) of neutral lithium atoms from oxidized tungsten. A model has been suggested of the ESD processes from an oxidized tungsten surface. It has been shown the community and the difference of the ESD processes for high-energy and low-energy peaks in the atomic energy distributions.
Keywords: electron-stimulated desorption, adsorption, alkali metals.
Microtribological properties of metal-matrix nanocomposites based on the layered oxides which behave as the nanocontainers – page 278
A.S. Logvinovich, T.V. Sviridova, D.V. Sviridov, A.V. Kaparikha
Abstract: The paper demonstrates the possibility of electrochemical synthesis of nickel-based metal-matrix composites doped with dispersed molybdenum oxide phase, which is capable to play a role of container of corrosion inhibitor that have a significant effect on the micro- and macrotribological properties.
Keywords: atomic-force microscopy, microtribology, metal-matrix composites, molybdenum trioxide, galvanic nickel coatings, benzotriazole, container systems.
Analysis of the spd method for determining anisotropy fields of ferromagnetic polycrystals – page 283
М.B. Lyakhova, O.V. Zhdаnova, Е.М. Semenova, Yu.G. Pastushenkov, D.Yu. Karpenkov, A.Yu Karpenkov, M.V. Filimonov
Abstract: The simulation results on the magnetization curves I(H) and the d2I(H)/dH2 dependences are presented. For this purpose models of rotation of the magnetization vector and the Néel model of magnetic phases were used. Recommendations for implementing the SPD-method for the anisotropy field determining for polycrystalline multidomain samples of ferromagnetic compounds with easy-axis MCA are proposed.
Keywords: SPD-method, magnetocrystalline anisotropy, anisotropy field, magnetization curve.
On the dependence of the phase diagram of a substitutional alloy on size and shape of a nanocrystal – page 291
M.N. Magomedov
Abstract: A method for calculating of solidus and liquidus temperatures for a disordered substitutional alloy is proposed. The method was tested on the SiGe alloy and it was obtained a good agreement with experimental data. It is shown that when the size of a nanocrystal of the solid substitution solution decreases, the difference between the liquidus and solidus temperatures decreases the more, the more noticeably of the nanocrystal shape is deflected from the most energetically optimal shape.
Keywords: substitution alloy, temperatures of solidus and liquidus, nanocrystal.
Surface properties of alkaline metals in the electric field in view of relaxation – page 301
A.R. Manukyants
Abstract: Influence of the surface relaxation on the surface energy of low-index faces of alkaline metals is considered. It is shown, that compression of interplane distances is observed on friable faces (111) in all cases, and either a stretching or absence of relaxation is observed on close-packed faces (110) for Li and K. Presence of a field strengthens the surface relaxation and changes the value of the surface energy.
Keywords: surface energy, relaxation, electronic work function.
Interactions of the phases containing calcium and aluminium as a part of red mud with ammonium hydrofluoride – page 307
I.S. Medyankina, L.A. Pasechnik, V.M. Skachkov, S.P. Yatsenko, V.G. Bamburov
Abstract: Fluorination processes of calcium, aluminum and iron phases in the composition of alumina production red mud using ammonium bifluoride to develop conditions of separation multicomponent materials and extract the valuable products have been considered in this paper. It is found that interaction of Al2O3 and 3CaO · Al2O3 · 6H2O as a part of red mud with ammonium hydrofluoride takes place the formation of ammonium fluoroaluminates and their decomposition to simple fluoride under the elevated temperatures. Calcium containing phases are the most active components and already at the initial moment of contacting the reaction mixture are decomposed with the fluorite CaF2 formation which in the presence of fluorine-containing aluminum compounds at a temperature above 400°C is a part of calcium cryolite CalAlF5. The research allows to justify the direction of sequential processes to separate phase components of red mud after their fluorination.
Keywords: red mud, bauxite residue, tricalcium aluminate, ammonium hydrofluoride, ammonium fluoromellate, industrial waste, fluorination.
Physical and chemical properties of cement based on calcium phosphate suspensions – page 317
O.N. Musskaya, V.K. Krut’ko, A.I. Kulak
Abstract: The effect of phase composition, concentration of calcium phosphates suspensions and polymer binder on the physicochemical properties of calcium phosphate cements is found. It has been established that the introduction of monetite and polymers (polyvinyl alcohol, polyethylene glycol) in the composition of calcium phosphate cements makes it possible to increase their static strength up to 7,1 MPa varying the setting time from 1 min to 1,5 h.
Keywords: calcium phosphate cement, tricalcium phosphate, hydroxyapatite, monetite, polyvinyl alcohol, polyethylene glycol.
Modeling of processes of structure formation in bimetallic nanoalloys of different composition – page 323
V.S. Myasnichenko, N.Yu. Sdobnyakov, A.Yu. Kolosov, D.N. Sokolov, V.V. Kulagin, A.A. Khort
Abstract: In this work the processes of an internal structure formation in copper-bearing nanoalloys of silver, cobalt and palladium were studied using molecular dynamics with a modified tight-binding potential. For each bimetallic system, five chemical compositions with different proportions of copper atoms were investigated. Non-structural clusters, obtained by melting the primary fcc nanoparticles, were then subjected to freezing procedure at room temperature with a fixed cooling rate. It is shown that upon cooling from the liquid superheated phase it is possible to form structural domains of different internal structure, including multiple nuclei of icosahedral symmetry. Some criteria for obtaining the ordered structure of the nano-melting core with a dense packing of atoms are determined.
Keywords: nanoalloys, molecular dynamics, tight-binding potential, structure formation.
Thermal stability of copper clusters with the size of 100 – 150 atoms – page 330
V.S. Myasnichenko, P.M. Ershov, N.Yu. Sdobnyakov, R. Mikhov, L. Kirilov
Abstract: In the framework of this paper we have studied the thermal stability of copper clusters in the range of 100 – 150 atoms. The size of the copper nanocluster is determined, which has the greatest thermal stability in the size range under consideration.
Keywords: molecular dynamics, tight-binding potential, copper nanoclusters, melting point, thermal stability.
AFM research of morphology of surface layer sapphire after plasma surface treatment – page 337
R.R. Nagaplezheva, M.M. Orakova, V.K. Luev
Abstract: An AFM study of the sapphire surface after plasma treatment was carried out. The AFM images of the sapphire surface in the initial state and after plasma treatment are obtained. It is established that after plasma treatment the arithmetic mean deviation of the surface profile increases and the surface becomes more homogeneous.
Keywords: plasma, scanning probe microscopy, atomic force microscopy, sapphire.
Investigation of mechanical properties of silicene In a central force field model – page 341
Y.E. Nagorny, D.N. Politaev
Abstract: Numerical simulation of mechanical behaviour of graphene and silicene are made in the central forces field model approximation. Dependences of Young’s modulus and Poisson’s ratio are obtained from the sample sizes. Comparison of results is carried out.
Keywords: central force field, graphene, silicene, Young’s modulus, Poisson’s ratio.
Interrelation between optical and radiation resistance of lithium niobate crystals of different chemical composition – page 347
M.N. Palatnikov, N.V. Sidorov, O.V. Makarova, D.V. Ivanenko, S.L. Panasyuk, E.R. Kurkamgulova, I.V. Yudin
Abstract: Optical characteristics of nominally pure and Mg2+, Zn2+, Gd3+, B3+ cations doped LiNbO3 crystals were investigated. The radiation resistance of β- and γ- irradiated LiNbO3 : Zn crystals was studied. The features of the optical transmission of LiNbO3 : Zn crystals are determined in dependence on the type and dose of irradiation and the concentration of the doping additive.
Keywords: crystals, doping, lithium niobate, photorefractive effect, β- and γ- irradiation, optical and radiation resistance.
Structure and properties of lithium niobate ceramics produced from the batch of various genesis – page 356
M.N. Palatnikov, O.B. Shcherbina, S.M. Masloboeva, V.V. Efremov, D.V. Ivanenko, S.V. Vladimirova
Abstract: The paper compares the structure, mechanical and electrical properties of ceramics obtained on the basis of highly disperse monophasic lithium niobate powders synthesized by various ways.
Keywords: lithium niobate, dispersity, ceramics, probe microscopy, impedance-spectroscopy, microhardness, Yong modulus, mechanical and electrophysical properties.
Criteria of thermodynamic similarity: sources and forecast at the molecular level – page 363
G.G. Petrik
Abstract: One more control factor of a new one-parameter family of equations has been added to a number of known thermodynamic similarity criteria. Its relation to the characteristics of the molecular level is established. The results obtained earlier at the atomic-molecular level of modeling objects and interactions make it possible to predict the values of a number of criteria on the basis of minimal information about molecules.
Keywords: model of interacting centers, similarity criteria, control factor, spherical shell model, object rigidity, critical compressibility factor, prediction of similarity criteria.
The strain mechanisms in the reinforced graphene layered and matrix composites. Experiment and simulation – page 375
V.A. Polukhin, E.D. Kurbanova
Abstract: In the present article the comparative analysis of results of MD simulation and experiments concerning properties of nanocomposites (metals/graphene, Me: Mg, Al, Cu, Ni, Ti) was carried out. The possibilities of improvement of structural and thermodynamic stability of the metal/graphene interface states, determining the strengthen characteristics of examined nanocomposites, were considered.
Keywords: graphene, metallic nanofilms, hybridization, sorption, interface, layered nanocomposite, reinforcement, thermostability, strain.
Computer analysis of the sensory properties of nanostructured SnO2 films. 1. Calculation of conductivity in gas sensors based on SnO2 nanoparticles – page 383
L.V. Redel, S.L. Gafner
Abstract: For modeling sensory properties, tin dioxide SnO2 was used as the working layer. The paper presented the main possible conduction mechanisms and their computer analysis. Based on the results obtained by using of the model with only one contact between two particles, we concluded that the reduction of the contact area between SnO2 particles less than 30 nm can significantly improve the sensor sensitivity to dangerous gases.
Keywords: semiconductor, computer modeling, nanocompacted material, gas sensor.
Computer analysis of the sensory properties of nanostructured SnO2 films. 2. The percolation approach to development of gas-sustainable sensors – page 390
L.V. Redel, S.L. Gafner
Abstract: We propose a model of a gas sensor developed on the basis of the nanocrystalline layers of SnO2. The basis of the model is the account of the real morphology of SnO2 nanolayers, and that some of the constituent nanoparticles may be in the non-conducting state even when the interaction with the reagent gas. It is shown that this probability determined by the diameter of nanoparticles and degree of their connection during sintering of nanocrystalline powder. It is expected that the inclusion of percolation effects can significantly increase the sensitivity of gas sensors based on SnO2 nanofilms. The percolation threshold corresponding to the critical concentration of gas to be detected can be controlled by means of the average particle size used and by degree of porosity of the film.
Keywords: semiconductor, computer modeling, nanocompacted material, gas sensor.
Computer analysis of the sensory properties of nanostructured SnO2 films. 3. Analysis of susceptibility of SnO2 sensor to carbon monoxide – page 397
L.V. Redel, S.L. Gafner
Abstract: In the presented work, the conductivity of a metal oxide film consisting of SnO2 nanoparticles interconnected due to the interaction of the detectable gas (CO ) with the surface of the semiconductor layer was investigated. Conditions under which the percolation effects is possible are found and their role in the sensitivity of the gas sensor under consideration. It was concluded that the percolation threshold can be controlled by means of parameters that can be directly controlled.
Keywords: semiconductor, computer modeling, nanocompacted material, gas sensor.
Synthesis of nanodispersed titanium dioxide via PH-controlled polymerization of titanium acid – page 404
L.Yu. Sadovskaja, T.V. Sviridova, D.V. Sviridov
Abstract: The possibility of synthesis of nanodispersed titania employing polycondensation of titanium acid under the pH control is discussed. The resultant spherical TiO2 nanopartcles exhibits extra high light-induced oxidation activity remaining for some time even after termination of UV illumination. The nanodispersed titania readily penetrate into the surface pores and can be used for deposition of photocatalytic coatings by the impregnation technique.
Keywords: nanodispersed titanium dioxide, photochemistry, polycondensation of oxoacids of transition metals, UV irradiation.
Combined application of atomistic and thermodynamic simulations to investigation of size dependence of the melting temperature of metal nanoparticles – page 411
V.M. Samsonov, I.V. Talyzin, S.A. Vasilyev, A.Yu. Kartoshkin
Abstract: An approach to simulation of the nanoparticle melting is discussed which combines thermodynamic and atomistic (molecular dynamics) simulation of objects under consideration. The approach has been applied to study the size dependence of the melting temperature of Ni and Ag nanoparticles. Exemplifying on the size dependence of the melting temperature, a conclusion is made that in spite of a number of disputable topics of both thermodynamic and atomistic simulations, combined application of both methods make it possible to obtain some more reliable results and to justify some conclusions on the reliability of available experimental data.
Keywords: thermodynamic simulation, atomistic simulation, size dependence of the melting temperature, nanoparticles Ni, nanoparticles Ag.
Effect of treatment of molten quartz surface on its wetting by germanium droplets – page 422
V.M. Samsonov, I.A. Kaplunov, A.M. Ivanov, I.V. Talyzin, S.A. Tretyakov
Abstract: We have measured equilibrium contact angles formed by germanium droplets on surfaces of molten quarts and some other surfaces prepared by using different variants of abrasion, polishing and, in some cases, etching. Using the optical interference method, a roughness coefficient of the relief profile was measured. It has been found that, in dependence of the way of treatment of the solid surface, the equilibrium contact angle varies in a wide enough range: from 147° to 164°. A conclusion has been made that for the system under consideration the Wentzel-Deryagin equation is not fulfilled.
Keywords: wetting, equilibrium contact angle, germanium droplet, surface of molten quarts, treatment of the solid surface, Wentzel-Deryagin equation.
Research of parameters of a foam in the jet regime bubbler – page 430
G.I. Sverdlik, A.S. Vickrebenets, R.N. Maxsimov, A.Y. Ataeva
Abstract: Advantages of the foam regime in bubbling apparatuses for the dust collection are considered, in which it is possible to capture a wide dimensional spectrum of pulverized materials, including nanoparticles not captured by other dust collectors. An experimental laboratory facility for studying parameters for obtaining a foam regime in a jet bubbler is described. A table of values of parameters of a foam mode and their interrelations are discussed.
Keywords: dust and gas emissions, jet regime bubbler, foam mode, experimental installation, collision of jets, variation of parameters.
Dielectric and photovoltaic properties of heterostructure SiC / Si – page 435
O.N. Sergeeva, A.V. Solnyshkin, S.I. Gudkov1, S.A. Kukushkin, I.P. Pronin, G.M. Nekrasova
Abstract: The paper presents the results of a study of dielectric and photovoltaic properties of heterostructures SiC / Si with different conductivity type of silicon substrates. The stationary photovoltaic responses of the structures were observed under electromagnetic radiation in the wavelength range from 400 – 980 nm. It is shown that the phase of photovoltaic responses depends on the capacitance jump in C – V characteristics. Possible mechanisms of the photovoltaic phenomena in heterostructures SiC / Si are discussed.
Keywords: SiC / Si heterostructures, dilatation dipole, nanosized silicon carbide, photovoltaic response.
Research of photorefractive properties in lithium niobate crystals by raman and photoinduced light scatering – page 442
N.V. Sidorov, N.A. Teplyakova, M.N. Palatnikov
Abstract: In Raman spectra of LiNbO3 crystals with photorefractive response in Y(ZX)Y scattering geometry a significant widening was detected of the band with frequency 630 cm-1 4A1(TO) that corresponds to totally symmetrical vibrations of oxygen octahedra. Any analogous line widening was not observed in Y(ZZ)Y scattering geometry. Not only photorefractive effect but also degree of oxygen octahedra distortion contributes to the width of this band.
Keywords: single crystal, lithium niobate, doping, Raman spectroscopy, photoinduced light scattering, photorefraction.
Influence of water vapor and illumination on conductivity of tin dioxide thin films at room temperature – page 449
V.V. Simakov, I.V. Sinev, A.V. Smirnov, I.D. Osyko, A.I. Grebennikov
Abstract: Investigation results of water vapour and illumination influence on the conductivity of tin dioxide thin film based gas sensors are presented. According to literature it is known that water vapor has a donor effect on the conductivity of the tin dioxide (n-type semiconductor), i.e. its conductivity in the water vapor atmosphere increases. It was experimentally found that the presence of water vapor in the measuring chamber leads to an increase in the conductivity of the sensor (in the dark) or to a decrease in conductivity (when the active layer of the sensor is illuminated).
Keywords: gas sensors, thin films, tin dioxide, acceptor action of water vapor.
Composite solders on the basis of metal powders and gallium alloy – page 455
V.M. Skachkov, N.A. Shevyrev, L.A. Pasechnik, S.P. Yatsenko
Abstract: The article considers new structures of composite alloys based on gallium. The effect of composition of powder filler on the structure and properties of the solder to impart unique properties and expansion of applications. The strength properties, microstructure, and thermal stability of the original samples and derived products have been studied.
Keywords: metal powder, composite diffusion-hardening alloys, solders, structure, properties, microhardness, differential thermal analysis.
A mathemetical model of the charge accumulation and the spectrum formation in detectors on the basis of CdTe (CdZnTe) at the gamma-quanta irradiation – page 465
A.A. Smirnov, I.A. Kaplunov, A.A. Ol’nev, A.N. Nikiforova
Abstract: The features of spectrum formation in CdTe (CdZnTe) detectors under gamma quanta radiation are presented. The main characteristics of a semiconductor detector, i.e. the energy resolution and the registration efficiency, are determined. The results can be used as a basis for physical and mathematical models of operation of CdTe (CdZnTe) semiconductor detectors for registration of gamma- and x-ray radiation over a wide energy range.
Keywords: semiconductor detectors, cadmium telluride.
Corrosive properties of coatings based on Ti1-xAlxN – page 475
Т.О. Soshina
Abstract: Corrosion properties of coatings based on Ti1-xAlxN precipitated by pulsed magnetron sputtering were studied. The effect of phase composition, aluminum content in Ti0,40Al0,60N and Ti0,62Al0,38N coatings on their electrochemical characteristics obtained in 0,3% NaCl solution was established.
Keywords: pulsed magnetron sputtering, Ti1-xAlxN coating, elemental composition, phase composition, the potential for free corrosion, the polarization curve, electrochemical characteristics, pitting corrosion.
Structure and electronic properties of the hybrid carbon phase formed by polymerization of bundles of nanotubes (6,0) – page 481
M.I. Tingaev, E.A. Belenkov
Abstract: Geometrically optimized structure and electronic properties of a new carbon phase consisting of carbon atoms in sp2 and sp3 hybridized states are calculated by the density functional theory method. The initial structure of the phase was constructed with partial cross-linking of the bundles of carbon nanotubes (6,0). The calculated sublimation energy of the sp2 + sp3 structure is 7,49 eV/atom. The density of electronic states at the level of the Fermi energy is zero, the width of energy gap band is 0,54 eV.
Keywords: carbon, crystal structure, carbon nanotubes, hybrid compounds, hybridization of atomic orbitals, density of electronic states.
Nano- and microsized heterodiamonds obtained from mixtures of carbon nitride and melamine with boron – page 488
V.P. Filonenko, I.P. Zibrov, A.S. Anokhin
Abstract: The paper presents experimental results of the synthesis under high pressure and temperature conditions of individual nano- and micron-sized heterodiamond crystals from mixtures of carbon nitride and melamine with boron. Heterodiamonds have the basic structure of cubic boron nitride, in which carbon occupies the positions of boron and nitrogen, and oxygen – only nitrogen ones. It is established that oxygen is responsible for the unit cell of boron nitride increase. It can enter to the lattice only if there is a deficit of nitrogen relative to boron.
Keywords: high pressure and temperature, boron nitride, carbon, boron, synthesis, heterodiamonds.
Gibbs potential of particles on two-dimensional lattice in the muffin-tin model – page 495
S.A. Khubezhov, V.I. Kesaev, I.V. Tvauri, A.P. Bliev, O.G. Ashkhotov, T.T. Magkoev
Abstract: The system of N identical particles in the tight bonding model on two-dimensional square periodic lattice, developed by axisymmetric partially-constant potential well, is considered. The chemical and thermodynamic Gibbs potentials of the system in Boltsman approximation are calculated.
Keywords: potential, particle, lattice, theorem, function, level, crystal, model, reaction, equation, approximation, zone.
Thermodynamic stability of CuxAg1-x nanoparticles – page 500
I.V. Chepkasov, N.D. Artemova, V.S. Baidyshev
Abstract: Molecular dynamics method was applied to simulate processes of melting of disordered CuAg alloy particles in the D = 3 – 5 nm size range. It is shown that for small nanoparticles (diameter D = 3 nm) melting process is associated with formation of an outer layer consisting of Ag atoms and further transition of the particle to an amorphous state. With increasing the particle size to D = 5 nm, this effect was not observed.
Keywords: computer simulation, molecular dynamics, CuAg nanoalloy.
Estimation of stability of CuAu nanoparticles of different type – page 505
I.V. Chepkasov, A.Yu. Baev, V.S. Baidyshev
Abstract: The thermal stability of the structure of nanoparticles (D = 5 nm) of various types (binary alloy, core-shell, «Janus» type) and with different percentage of copper atoms was studied by molecular dynamic simulation. The most thermodynamically advantageous variants of the structure were determined and the influence of various temperatures on the structural stability of these nanoparticles was studied.
Keywords: nanoparticles, gold, copper, EAM potential, structure.
Wetting of copper surface by solid nanosized lead particles: molecular dynamics study – page 510
A.V. Chirkov, V.M. Samsonov
Abstract: Using molecular dynamics method, the solid state wetting in the system Pb (nanoparticle) / Cu (substrate) has been observed and studied. It has been found that the solid state spreading mechanism corresponds to the surface diffusion developed via the linear dependence of the square first monolayer radius on the spreading time. From the dependence in question, the surface diffusion coefficient was evaluated.
Keywords: solid state wetting, surface diffusion, nanoparticles, surface, molecular dynamics.
Contribution of dispersion interaction of s-spheres into the interfacial energy of α – Li and α – Na crystals bounding non-polar organic liquid boundary – page 518
I.G. Shebzukhova, A.M. Apekov
Abstract: The contribution of the dispersion interaction into the interfacial energy of lithium and sodium BCC-crystals has been found on the boundaries with non-polar organic liquids on the grounds of the electron-statistical method as well as the E.M. Lifshits theory.
Keywords: dispersion interaction, interface energy, electron-statistical method, lithium, sodium, non-polar organic liquid, theory by E.M. Lifshits.
Formation of microstructure of Bi-40 wt. % Sn alloy during hightspeed crystallization – page 522
V.G. Shepelevich
Abstract: Rapidly solidified foils of Bi – 40 wt. % Sn have homogeneous distribution bismuth and tin phases with microcrystalline structure. Its formation is caused by the spinodal decay of supercooled supersaturated liquid solution and subsequent nucleation and growth of centers of crystallization in areas rich in bismuth and tin.
Keywords: hightspeed crystallization, foil, phase, grain, bismuth, tin, spinodal decay.
Technological approaches for modified multilayer coatings formation based on nanostructured porous anodic Al2O3 and deposited dielectric films – page 529
D.L. Shimanovich
Abstract: Technological methods and conditions for additional inorganic dielectric films formation using the vacuum deposition on nanostructured porous alumina bases are investigated. Modified multilayer structures with closed porosity have been obtained. The improvement of thermophysical and electrophysical properties of finite dielectric coatings on aluminum substrates is demonstrated.
Keywords: aluminum, electrochemical anodization, porous anode alumina, nanostructured material, vacuum deposition, thermophysical and electrophysical properties.
Scanning electron microscopy in studying biocomposites with metal or organic scaffolds – page 536
A.G. Shirokova, E.A. Bogdanova, V.M. Skachkov, I.G. Grigorov, N.A. Sabirzyanov
Abstract: The authors proposed a new method of investigation of the microstructure of biocomposites with a metallic or organic matrix by scanning electron microscopy. Using the ScanMaster program 3D-images of highly porous honeycomb materials with HAP-coating were formed. The planar and spatial morphometric parameters of investigated objects for implant purposes were obtained.
Keywords: highly porous honeycomb materials (HPHM), hydroxyapatite (HAP), coating, biocomposites, scanning electron microscopy.
Investigation of electromass transfer in the borate-barium glass – page 544
Z.V. Shomakhov, O.A. Molokanov, A.M. Karmokov
Abstract: The results of investigation of processes occurring under heating and in isothermal conditions during the passage of electric current through borate-barium glass С78 – 5, applied in electronic engineering, are presented. Experimental data have been used to determine the dependence of the specific electric conductivity on the temperature and on the annealing time for a continuous unidirectional current through the sample, and also for a symmetric alternating current excluding electromass transfer.
Keywords: isothermal annealing, kinetics of electrical conductivity, borate-barium glass, structural transformations, specific electric conductivity, phase formation, activation energy of electrical conductivity.
SURFACE MODIFICATION OF STRONTIUM HEXAFERRITE COLLOIDAL NANOPARTICLES BY SILICA COATING – page 5.
E.O. Anokhin, L.A. Trusov, A.V. Vasiliev, A.E. Sleptsova, A.A. Eliseev, E.A. Gorbachev, P.E. Kazin
Abstract: We report a technique for producing hard-magnetic strontium hexaferrite colloidal particles with silica-modified surface. Three types of nanomaterials can be obtained by varying the synthesis conditions: «core-shell» particles; silica gels and sols filled with uniformly distributed hexaferrite particles.
Keywords: strontium hexaferrite, magnetic nanoparticles, magnetic fluids, colloids, silica, core-shell, coating.
COMPARATIVE INVESTIGATION OF THE CURRENT-VOLTAGE CHARACTERISTICS OF TUNELLING CONTACT FOR NANOSIZED GOLD AND SILVER FILMS – page 13.
A.S. Antonov, D.V. Ivanov, I.I. Sorokina, N.Yu. Sdobnyakov
Abstract: A comparative investigation of the current-voltage characteristics of the gold and silver film samples with tungsten tip proves that experimental results demonstrate the need for careful analysis of the parameters affecting the tunneling current to receive additional information about the electronic structure of the sample.
Keywords: scanning tunneling microscopy, gold, silver, mica, current-voltage characteristic, the thermal expansion of the tip.
TEMPERATURE CONTRIBUTION TO THE INTERFACIAL ENERGY OF THE CRYSTAL FACES OF Sc, α – Ti AND α – Co AT THE BOUNDARY WITH THE ORGANIC LIQUIDS – page 19.
A.M. Apekov, I.G. Shebzukhova
Abstract: We developed a modified version of the electron – statistical method of calculation of the temperature contribution to the interfacial energy of the metal on the boundary with non-polar organic liquids. The dependence of the temperature contribution to the interfacial energy of Sc, α – Ti and α – Co metal on the orientation of the crystal and the dielectric permeability of the liquid has been obtained.
Keywords: interfacial energy, temperature contribution, scandium, titanium, cobalt, electron-statistical theory.
THE SIZE AND CONCENTRATIONAL DEPENDENSE OF THE SURFACE ENERGY OF THIN FILMS OF THE TRANSITIONAL METAL ALLOYS – page 26.
L.P. Aref`eva, I.G. Shebzukhova
Abstract: On the bases of thermodynamic model we have obtained the ratio for the bond energy of alloy crystals. The modified electron-statistical method has reproduced size and concentration dependences of the surface energy of thin films of the transitional metal alloys.
Keywords: surface energy, concentration dependence, thin films.
THE RATE OF CONTACT MELTING AND PHASE TRANSFORMATION IN THE PAIR COPPER / ALUMINUM OF AMG-2 BRAND SYSTEM – page 32.
A.A. Ahkubekov, P.K. Korotkov, M.Z. Laypanov, A.R. Manukyants, M.Kh. Ponegev, V.A. Sozaev
Abstract: Studying of the contact melting (CM) in Cu / Al system plays an important role for the development of technology of the contact – reactive soldering. Also the data on CM can be of interest at design of layered intermetallic composite material of the system Cu – Al, by development of heat-dissipating devices, powerful high-frequency diodes and transistors. In the present work an attempt is made to reveal features of the structure of contact layers at contact melting of copper with aluminum of the AMG-2 brand (addition of Mg ~ 2 wet. %, the rest aluminum) and to fix influence of Mg impurity on the time dependence of the thickness of a contact layer for system Cu / Al.
Keywords: contact melting, intermetallics, phase formation, impurity.
MESOSCOPIC SIMULATION OF ENZIMLIKE NANOSTRUCTURS ON BASE OF N-VINYLCAPROLACTAM AND N-VINYLIMADAZOLE – page 36.
P.O. Baburkin, P.V. Komarov
Abstract: We present new results of computer simulations of synthesis of block A – AB copolymers. Our model shows that compact and water-soluble globules, which can be used as basis for sinzymes, can be obtained in narrow range of investigated parameters.
Keywords: coarse-grained computer simulation, amphiphilic copolymers, protein-like polymers, enzyme.
INFLUENCE OF ELECTOMIGRATION ON THE FORMATION OF A TRANSIENT ZONE IN CONTACT OF SOLID BODIES AT A TEMPERATURE BELOW THE MELTING POINT OF A LOW-MELTING COMPOUND – page 41.
A.M. Bagov
Abstract: A number of new systems has been increased in which the decrease of the temperature of a phase transition (melting) in the contact of pairs of solid heterogeneous metals (with differing state diagrams) can be observed. The joining of samples has been revealed in all studied systems and takes place in some temporal and temperature ranges specific to each pair of metals. The experiments have been conducted at the presence of electromigration. The passing current helps to identify the mentioned process.
Keywords: contact melting, electromigration, metals, alloys, diffusion, delta Т – effect, metastable contact melting, intermetallics, eutectics.
NONLINEAR CRYSTALLIZATION KINETICS OF LONG CHAIN POLYMER MATRIX INTO HIGH FULL COMPOSITES – page 46.
B.K. Barakhtin, R.V. Sedletsky
Abstract: The polymer matrix composites samples have been investigated. The volume portions filling was ranged from 0,45 to 0,65. At the density, modulus of elasticity, strength and pitch amorphous coefficient increasing background, the quasi-periodical oscillations for the first time were fixed. Structure investigations with electron scanner and atomic force microscopes were carried out.
Keywords: polymer composite materials, mechanical tests, structure investigations.
THE SYNTHESIS OF COMPOSITES BASED ON POWDERS OF ALUMINIUM WITH SMALL ADDITIONS OF BARIUM – page 59.
S.A. Bibanaeva, V.M. Skachkov, B.N. Latosh, N.A. Sabirzyanov
Abstract: The article describes a method of producing a porous material of aluminum powders doped with small additions of barium after treatment with water. Studies of the strength properties, microstructure, specific surface area of the original samples and derived products were performed.
Keywords: aluminium powder, barium, cermet, specific surface, microhardness, scanning microscopy.
THE EFFECT OF THERMAL ANNEALING ON THE STRENGTH OF BIOACTIVE COATING ON THE POROUS TITANIUM – page 64.
E.A. Bogdanova, V.M. Skachkov, A.G. Shirokova, I.G. Grigorov, N.A. Sabirzyanov
Abstract: A number of works on creation of biocomposites based on highly porous titanium coated with hydroxyapatite (HAP) was conducted. Features of formation of the surface layer with the combination of the vacuum impregnation method and thermal annealing have been investigated. The effect of the heat treatment on the adhesive properties of the biocoatings is studied.
Keywords: composite biomaterial, bioactive coating, heat treatment, adhesion strength, hydroxyapatite (HAP), porous titanium.
DEVELOPMENT OF MODIFIED TECHNOLOGY OF PRODUCING NANOSTRUCTURAL MAGNETIC OIL – page 69.
A.N. Bolotov, V.V. Novikov, O.O. Novikova
Abstract: In the present work a technology is discussed of producing magnetic grease oil on the basis of a chlorsiloxane including synthesis from its molecules of the surfactant stabilizing magnetite particles. The obtained oil has high tribotechnical properties during the work in extreme service conditions.
Keywords: nanostructural magnetic oil, friction.
SYNTHESIS OF CARBON NANOSTRUCTURES FROM METHANE BY PLASMA-CHEMICAL METHOD – page 76.
Yu.V. Brylkin, G.N. Zalogin, A.V. Krasilnikov, N.F. Rudin
Abstract: The possibility of synthesis of carbon nanostructures by plasma-chemical method based on the decomposition of methane in an argon plasma is shown.
Keywords: scanning tunneling microscopy, electron microscopy, RF plasma torch, carbon materials.
STUDY OF PHASE FORMATION IN THE SYSTEM SrO – Fe2O3 – MoO3 – B2O3 – page 82.
A.V. Vasiliev, A.G. Fedorovskiy, A.A. Sycheva, L.A. Trusov, E.O. Anokhin, P.E. Kazin
Abstract: Oxide glasses were obtained by high-speed melt quenching. The glass ceramic samples were prepared by thermal crystallization method in reducing atmosphere. The phase composition and magnetic characteristics of the glass-containing Sr2FeMoO3 are investigated.
Keywords: strontium hexaferrite, magnetic nanoparticles, magnetic fluids, colloids, colloidal stability.
SYNTHESIS OF EXCHANGE-COUPLED COMPOSITE BASED ON SrFe10,7Al1,3O19 / Co CORE/SHELL PARTICLES – page 88.
E.A. Gorbachev, L.A. Trusov, A.A. Eliseev, A.E. Sleptsova, E.A. Anokhin, A.V. Vasiliev, P.E. Kazin
Abstract: Exchange-coupled core/shell-structured magnetic materials can be potentially used as rare-earth free permanent magnets, but their synthesis presents a challenge. We report a wet chemistry method to synthesize core/shell structured particles consisting of a magnetically hard SrFe10,7Al1,3O19 core and a soft Co shell.
Keywords: magnetic materials, composites, hexaferrites, chemical synthesis, nanostructures.
QUANTUM-CHEMICAL MODELING OF CLUSTERS Bi(N-n)Sbn – page 95.
E.N. Gribanov, O.I. Markov, Yu.V. Khripunov
Abstract: In the present article the results are presented of quantum-chemical modeling of clusters of bismuth-antimony. Physico-chemical characteristics of the clusters of various compositions are calculated.
Keywords: cluster, bismuth, antimony, the transition semiconductor-semimetal.
INVESTIGATION OF INTERPHASE BOUNDARIES SYSTEMS Ag / TiO2, Au / TiO2, Ag / MoO3, Au / MoO3 – page 100.
G.S. Grigorkina, S.A. Khubezhov, I.V. Tvauri, O.G. Ashkhotov, I.B. Ashkhotova, E.N.Kozirev, V.B.Zaashvili, M. Wilde, D. Sekiba, S. Ogura, K. Fukutani, T.T. Magkoev
Abstract: The supported metal/oxide systems consisting of Au and Ag metal clusters, deposited on the surface of TiO2 and MoO3 in high vacuum, have been studied by means of X-ray photoelectron spectroscopy and X-ray diffraction. The major feature for all the studied systems is the reduction of the oxide at the contact interface by the deposited metal. The minor details differentiating Au and Ag, as well as TiO2 and MoO3 are determined by the differences in electronic structure of Au and Ag, TiO2 and MoO3, as well as their transformation at the contact.
Keywords: surface, border, interfacial oxide, metal, vacuum, diffraction, photoelectron spectroscopy, molybdenum, titanium, gold, silver.
THE STUDY OF HYDROXYAPATITE CONTAINING BIOCOMPOSITES BASED ON TITANIUM WITH VARYING POROSITY BY SCANNING ELECTRON MICROSCOPY – page 105.
I.G. Grigorov, A.G. Shirokova, E.A. Bogdanova, V.M. Skachkov, O.V. Skachkova, N.A. Sabirzyanov
Abstract: The work provides morphological and topographical data of the surface of synthesized biocomposites, with the aim of using them for bone implants obtained by scanning electron microscopy. As a metallic matrix, titanium of different porosity was selected, bioactive coating was formed by various methods from an aqueous suspension of hydroxyapatite. For coated samples 2D- and 3D- surface images were obtained using the Scan Master program.
Keywords: implant, biocomposites, titanium, hydroxyapatite (HAP), 2D- and 3D-images, scanning electron microscopy.
QUANTUM CHEMICAL MODELING OF THE MOLECULAR AND ELECTRONIC STRUCTURES OF THE ESTRON-CONTAINING BISFULLERENOL RADIONUCLIDE CANCER FIGHTING AGENTS – page 110.
E.A. Dikusar, A.L. Pushkarchuk, T.V. Bezjazychnaja, A.G. Soldatov, S.A. Kuten
Abstract: DFT-modeling of the molecular and electronic structures of the estron-containing bisfullerenol radionuclide cancer fighting agents has been carried out.
Keywords: DFT-modeling of the electronic structure, estron, bis-fullerenol radionuclide clusters, cancer fighting agents.
EFFECTS OF WATER SOLUBILITY IN ALKANES AND INTERFACE CHARGING ON STABILITY OF SHORT CHAIN ALKANE NANOFILMS ON WATER – page 119.
K.A. Emelyanenko
Abstract: Influence of water solubility in alkanes and charging of water/oil interface on the stability of alkane film was studied. Taking into account interactions, caused by charging and polarization of interfaces, as well as dissolution of water molecules inside the film, allows calculating equilibrium film thickness as a function of water concentration. Results indicate significant effects of dissolved water on the film thickness.
Keywords: disjoining pressure, wetting films, stability, image charge forces, Van-der-Waals forces, water solubility in alkanes.
ANALYSIS OF THE POSSIBLE USE OF NANOCLUSTERS OF Pt, Pd AND THEIR ALLOYS FOR RECORDING INFORMATION – page 128.
I.S. Zamulin, L.V. Redel
Abstract: On the basis of a computer simulation the possibility is evaluated of using individual nanoclusters of Pt and Pd as well as Pt – Pd nanoalloy particles as bits of information built on the principle of changing the phase state of the carrier. It is concluded that the most appropriate material to create the memory elements are nanoclusters of alloy Pt – Pd with 10% content of platinum atoms and diameter D ≥ 3,5 nm.
Keywords: computer simulation, molecular dynamics, nanoclusters, platinum, palladium, phase transitions, memory cells.
LIGHT INDUCED THERMODIFFUSION OF NANOPARTICLES – page 135.
V.I. Ivanov, G.D. Ivanova
Abstract: We have analyzed the optical transmittance response of thin cell with liquid containing absorbing nanoparticles in a Gaussian beam field. The transmittance spatial changing is caused by the thermal diffusion phenomenon (Soret effect) which produces the variations of concentration of absorbing nanoparticles.
Keywords: radiation, nanoparticle thermodiffusion, non-linear absorption.
THE INFLUENCE OF SURFACES NANOTOPOGRAPHY ON CHARACTERISTICS OF SOLIDS DISCRETE CONTACT – page 139.
V.V. Izmailov, M.V. Novoselova
Abstract: The influence of nanoscale deviations of real surfaces of engineering devices from the perfect shape (nanoroughness) on real contact area has been considered. The real contact area ensures the electrical charges or heat transport through the contact of solids. It is shown that the neglecting of the nanoroughness in significant overestimation of real contact area.
Keywords: surface, contact, nanoroughness, contact area.
PROPERTIES OF GADOLINIUM DOPED AMORPHOUS SILICON DIOXIDE NANOPOWDERS, PREPARED BY PULSED ELECTRON BEAM EVAPORATION – page 145.
V.G. Il`ves, S.Yu. Sokovnin, A.M. Murzakaev
Abstract: Amorphous silicon dioxide nanopowders doped with Gd (specific surface area of 175 to 212 m2/g) were prepared using the pulsed electron beam evaporation of the target presented by mechanical mixtures of amorphous Aerosil 90 (90 m2/g) and Gd2O3 powder (REO 99,9%). The obtained particles are small (less than 10 nm) and of high interparticle porosity and high concentration of gadolinium dopant, that indicates on the possibility of using the prepared nanoparticles SiO2 – Gd2O3 as contrast agents for magnetic resonance imaging.
Keywords: pulsed electron beam, the amorphous-nanocrystalline powders SiO2 – Gd2O3.
ELECTROMASSTRANSPORT IN GLASSES FOR ELECTRONICS – page 151.
A.M. Karmokov, O.A. Molokanov, Z.V. Shomakhov
Abstract: The results are presented of the investigation of the influence of heating and isothermal exposure on the electrical conductivity special glasses C87 – 2, C78 – 4 (lead-silicate) and C78 – 5 (borate-barium) which are applied in electronics.
Keywords: borate-barium glass, ionic conductivity, crystalline phase, nanoscale phase, annealing, lead-silicate glass, electromasstransport, electrical conductivity, electrical conductivity activation energy.
THERMODYNAMIC ANALYSIS OF PHASE FORMATION IN STAINLESS STEEL TREATED WITH A HIGH-INTENSITY PULSED ELECTRON BEAM – page 155.
A.A. Klopotov, Yu.F. Ivanov, V.A. Vlasov, A.I. Potekaev
Abstract: A thermodynamic analysis of phase transformations occurring during heat treatment of the alloy Fe – Cr – Ni – C, which is the basis of steel AISI 321, is carried out. The results of the analysis of the elemental and phase composition, the defect substructure of stainless steel caused by the irradiation with a high-intensity pulsed electron beam are presented.
Keywords: stainless steel, phase diagram of state, high-intensity pulsed electron beam, structure, properties.
DIFFUSION PROCESSES IN NANOSCALE NaAuy FILM – page 164.
M.V. Knatko, M.N. Lapushkin
Abstract: Alkali metal diffusion processes were studied in the semiconductor film NaAuy under the sodium flux modulation conditions deposited on the surface with the following thermal desorption. It is shown that the sodium ion emission in the surface ionization process is determined by a combination of adsorption and diffusion exchanges of Na atoms between surface and volume of the NaAuy film, as well as by diffusion processes within the film.
Keywords: adsorption, alkali metals, gold, intermetallic, thermal desorption of atoms and ions, surface ionization.
ABOUT ASSESSMENT OF DIHEDRAL ANGLE BETWEEN METAL NANOPARTICLES IN THE COALESCENCE PROCESS – page 172.
A.Yu. Kolosov, D.N. Sokolov, N.Yu. Sdobnyakov, P.V. Komarov, V.S. Myasnichenko, S.S. Bogdanov, A.A. Bogatov
Abstract: The Monte-Carlo simulation of the coalescence of gold, copper and silver nanoparticles of different shapes was carried out. The interaction between nanoparticles was described by the many-body Gupta potential. An algorithm for detection and assessment of the dihedral angle was developed. An assessment of the dihedral angle between metal nanoparticles in the coalescence process was carried out.
Keywords: coalescence, gold nanoparticles, copper nanoparticles, silver nanoparticles, Monte-Carlo method, Gupta interatomic potential, phase transition, neck formation.
THE INTERNAL ROTATION IN 1,n – DIFLUORINEALKANES – page 180.
A.V. Kotomkin, N.P. Rusakova, V.V. Turovtsev, Yu.D. Orlov
Abstract: Eight potential functions of the internal rotations around the C – C bonds in molecules 1,n-difluorine alkanes F – (CH2)n – F, where 3 ≤ n ≤ 6, were obtained and approximated by Fourier series. The local minima and transition states (TS) have been studied for all the examined compounds. A comparison of the rotation characteristics of studied molecules with same in 1-monofluorine alkanes was performed. The transferability of rotation parameters around C – C bonds has been showed.
Keywords: 1,n-difluorine alkanes, potential function, conformational analysis, internal rotation.
ELECTRONIC STRUCTURE OF NEW GRAPHENE POLYMORPHOUS TYPES – page 186.
A.E. Kochengin, E.A. Belenkov
Abstract: The structure of new polymorphic types of graphene was obtained as a result of different variants of linking of carbyne chains. Geometrically optimized structure and a number of properties of modelling derived layers were calculated using the density functional theory in the gradient approximation. As a result of calculations, the possibility of the stable existence of fifteen new polymorphic types of graphene were established, composed of carbon atoms in two or three different crystallographic positions. The band gap of eight polymorphs is zero, and for the rest is from 0,13 to 0,59 eV. The energy of sublimation for polymorphs L4-6-8a, L4-6-8b, L4-6-8c, L4-6-8e and L4-6-8f was higher than the values of the sublimation energy of main polymorphs of graphene (L4-8, L3-12 and L4-6-12), but lower than the energy of atomization of hexagonal graphene.
Keywords: graphene, polymorphism, electronic structure, computer modeling.
SURFACE MODIFICATION OF APATITE-POLYMER COATINGS BY ULTRAVIOLET RADIATION – page 195.
V.K. Krut’ko, A.I. Kulak, O.N. Musskaya, S.A. Ulasevich
Abstract: It has been found that ultraviolet radiation can enhance the degree of hydrophilicity of apatite-polymer coatings on the titanium surface, electrochemically deposited in a polyvinyl alcohol medium at a constant current density 10 – 60 mА/sm2 and the deposition time of 10 – 30 min.
Keywords: apatite-polymer coatings, polyvinyl alcohol, electrodeposition, ultraviolet radiation, hydrophilicity-hydrophobicity.
LIGHT INDUCED BUBBLE CLUSTERS – page 202.
A.A. Kuzin
Abstract: The formation of light induced bubble clusters on the liquid surface has been investigated experimentally. Ordered bubble clusters are formed by means of thermocapillary mechanism in a developed convection.
Keywords: mass transport in the binary media, microparticle thermocapillary drift, bubble cluster, light induced convection.
EFFECT OF PENETRATION DEPTH OF EXCITING ELECTRONS ON THE ELECTRON-STIMULATED DESORPTION YIELD – page 207.
Yu.A. Kuznetsov, M.N. Lapushkin
Abstract: We have studied the concentration dependences of electron-stimulated desorption (ESD) of Cs, Na, Sm, and Eu atoms upon their adsorption on nonmetallic layers of films grown on W substrate. It has been found that ESD processes occur at the adlayer – nonmetallic substrate interface. It has been also shown that reducing the ESD yield beyond one monolayer is due to a decrease in the number of exciting ESD electrons reaching the interface.
Keywords: electron-stimulated desorption, adsorption, alkali metals, rare-earth metals, gold, intermetallic compounds.
X-RAY AND MÖSSBAUER STUDY OF AMORPHOUS AND CRYSTALLINE FERROMAGNETIC MICROWIRES – page 214.
V.S. Larin, V.V. Korovushkin, A.T. Morchenko, L.V. Panina, V.G. Kostishyn, Yu.A. Lopatina, M.M. Salem, A.V. Trukhanov
Abstract: Study of amorphous ferromagnetic microwires in a glass shell before and after heat treatment under different conditions was performed by X-ray diffraction and Mössbauer spectroscopy. In the initial state, such microwires are of magnetically soft materials and show the effect of magnetic impedance used to create highly sensitive sensors. After procedure of the directional solidification, wires with a high cobalt content have hard magnetic properties and can serve as permanent magnets in devices of Microsystem engineering and other applications. To identify the processes occurring at transformation of the wire substances from amorphous to nano- and/or microcrystalline state, it was studied features of the wire structure.
Keywords: amorphous ferromagnetic microwires, magnetically soft\hard alloys, magnetic impedance, micromagnets. directional solidification, nanocrystalline state, coercivity, magnetic anisotropy.
SELF-HEALING COATINGS MADE OF METAL-MATRIX NANOCOMPOSITES COMPRISING LAMELLAR OXIDES EMPLOYED AS THE CARRIERS OF FUNCTIONAL COMPOUNDS – page 225.
A.S. Logvinovich, T.V. Sviridova, D.V. Sviridov, A.V. Kaparikha
Abstract: The paper results demonstrate the possibility of electrochemical synthesis of nickel-based metal-matrix composites doped by dispersed tungsten oxide which is capable to play role of dispenser of incorporated compounds of different functionality.
Keywords: metal-matrix composites, tungsten trioxide, electrochemical synthesis, electrochemical nickelcoating, benzotriazole, corrosion resistance.
THE DEPENDENCE OF THE VACANCY CONCENTRATION FROM THE SIZE AND SHAPE OF THE NANOCRYSTAL AT DIFFERENT PRESSURES – page 231.
M.N. Magomedov
Abstract: On the basis of generalized RP-model of the nanocrystal, in which there are vacancies in the lattice and the delocalized (diffusing) atoms, the expression for the Helmholtz free energy and the equation of state for the nanocrystal were obtained. The change in the probability of the vacancy formation and the probability of delocalization of an atom, depending on the size and shape of the nanocrystal at different temperatures and pressures were studied. The calculations are performed for BCC iron.
Keywords: vacancies, self-diffusion, nanocrystal, pressure, iron.
OBTAINING AND RESEARCH OF MICROCRYSTAL POWDERS OF LITHIUM NIOBATE AND TANTALATE – page 239.
S.M. Masloboeva, M.N. Palatnikov, L.G. Arutjunjan, D.V. Ivanenko
Abstract: A method of synthesis of microcrystal single phase high disperse powders of lithium niobate and tantalate with and narrow distribution of particle size was developed. Researches of final and intermediate products were carried out by differential thermal analysis, X-ray analysis, IR-spectroscopy, crystal optics, low-temperature nitrogen adsorption. Powder fractions 1 – 5µ and 5 – 10µ were obtained by decantation for different technical applications.
Keywords: lithium niobate (tantalate), niobium (tantalum) hydroxide, lithium acetate and citrate, liquid phase synthesis, annealing, fractioning.
PHASE TRANSITIONS IN THE FRUSTRATED ISING MODEL ON TRIANGULAR LATTICE – page 247.
A.K. Murtazaev, M.K. Ramazanov, M.K. Badiev
Abstract: Critical properties of an antiferromagnetic Ising model on a triangular lattice with interactions of the next-to-nearest neighbors are investigated by a replica Monte-Carlo method. Using the finite-size scaling theory the static critical exponents of specific heat, ordering parameter, susceptibility, correlation radius as well as the Fisher exponent are calculated.
Keywords: Monte Carlo method, Izing model, phase transition, antiferromagnetic frustration.
CELLULAR AUTOMATA MODEL OF THE TWO-DIMENSIONAL SINGLE COMPONENT AND BINARY NANOCRYSTALS GROWTH – page 253.
V.S. Myasnichenko, A.Yu. Kolosov, N.Yu. Sdobnyakov
Abstract: This paper describes a discrete model layered growth of nanocrystals and nanoalloys based on mathematical tools of cellular automata. It is shown that with the help of set of simple rules on a hexagonal grid we can simulate various physical characteristics of the self-organizing process, including atomic segregation and vacancies formation.
Keywords: discrete simulation, cellular automata, crystal, ultra-thin film, nanoalloy, spatial self-organization.
EFFECT OF EXTERNAL PRESSURE ON THE PHASE TRANSITION TEMPERATURE IN BIMETALLIC ARGENTIC NANOPARTICLES – page 259.
V.S. Myasnichenko, V.V. Kulagin, D.N. Sokolov, N.Yu. Sdobnyakov, L. Kirilov
Abstract: In this paper, a series of computer experiments on heating of clusters in the form of a truncated box is made by a molecular dynamics method (NPT ensemble). Clusters of the stoichiometric compositions AB and A3B were investigated for Cu – Ag and Au – Ag bimetallic systems. We used a modified many-body tight-binding potential. It was found that the temperature range of the structural stability for bimetallic nanoparticles (nanoalloys) have combined influence of the following factors: nanoparticle size and initial geometric form, nanoparticle composition, type and degree of atomic ordering, external pressure.
Keywords: external pressure, melting temperature, structural phase transition, bimetallic clusters, «core-shell» structure, silver nanoparticles, molecular dynamics method.
INSTALLATION FOR RESEARCH ON INFLUENCE OF PLASMA TREATMENT PHOTOELECTRON EMISSION – page 266.
R.R. Nagaplezheva, M.M. Uyanaeva
Abstract: The plasma treatment of the surface of sapphire was performed. The composition of the sapphire surface before and after plasma treatment was investigated by X-ray photoelectron spectroscopy (XPS).
Keywords: plasma, photoelectron emission.
ON THE SIZE DEPENDENCE OF THE ABSORPTION COEFFICIENT OF NANOSCALE FILM OF ETHANOL ON SILICON SUBSTRATE – page 269.
N.V. Novozhilov, N.Yu. Sdobnyakov, I.D. Rodin
Abstract: Using photometric spectroellipsometer «El`f» based on the spectrum analysis of the ellipsometric angles ψ and Δ, the investigation was performed of the size dependence for the absorption coefficient of ethanol film on silicon substrate.
Keywords: ellipsometry, nanoscale liquid films, absorption coefficient, ethanol, silicon.
TEMPERATURE RESISTANCE OF ELECTROMECHANIC CHARACTERISTICS OF Y + 42° -CUT LiTaO3 SINGLE CRYSTALS – page 273.
M.N. Palatnikov, V.A. Sandler, N.V. Sidorov, O.V. Makarova
Abstract: The temperature resistance of electromechanic characteristics of Y + 42° -cut LiTaO3 single crystals was investigated by dielectric spectroscopy and research of static and dynamic piezoelectric effect. Clear influence of the thermal history of crystal samples at thermocycling on resonance characteristics (values of resonance and antiresonance frequencies) was revealed.
Keywords: single crystals, lithium tantalate, piezoelectric modulus, electromechanic resonance, residual deformation, anisotropy, thermal history, thermocycling.
STUDY OF ATOM BOMBARDMENT ISOMERS CLUSTERS Ti7. MOLECULAR DYNAMICS SIMULATION – page 280.
N.A. Pan’kin
Abstract. Molecular dynamics has been performed of synthesis processes and ion bombardment titanium clusters Ti7 with pentagonal bipyramid structures (space group – D5h) and octahedron with an attached one of its faces a tetrahedron (C3υ). It is shown that an increase in the synthesis temperature is accompanied by increased frequency of the low-energy D5h structure. The initial temperature of isomers (up to 300K) does not affect the interaction of the ion-cluster. The distribution of the particles formed as a result of cluster ion bombardment, according to their size. We construct the energy spectrum and the function for scattering angles for the distribution of ions and atoms and their analysis.
Keywords: cluster, isomers, bombardment, distribution function, space group.
ANALYSIS OF MOLECULAR MODELS UNDERLYING LOW-PARAMETRICAL EQUATIONS OF THE STATE: FROM EMPIRICAL MODIFICATIONS TO PHYSICALLY REASONABLE MODELS – page 292.
G.G. Petrik
Abstract: The paper presents some results of systematic approach to the search of physically reasonable equations of the state (EOS). The main result is that a large group of cubic EOS of VDV-type fits into the scope of the studied molecular model of interacting centers; it allows eliminating their basic disadvantage – poor connection with the micro-level.
Keywords: equation of state, control parameter, interacting centers model, Van der Waals equations of state, intermolecular interaction.
THE FORMATION OF THE INTERMEDIATE ORDER IN THE METGLASSES AND THE LONG ORDER IN NANOCRYSTALLINE ALLOYS TAKING IN ACCOUNT THE CHARACTER OF THEIR BONDS AND SHORT ORDER CHANGES – page 302.
V.A. Polukhin, E.D. Kurbanova, R.M. Belyakova
Abstract: Basing on the analysis of the available research data, the short and intermediate order of the structure formations in the amorphous as well as the long order in the nanocrystalline alloys have been revealed for both states of alloys considering with that their structures in corresponding atomic cluster configurations formed not only on the base of icosahedral packing but on the base of helicoid one with fraction symmetry supplying, for the inner structure of nanocrystalline alloys, the mutual coherence of crystalline and non-crystalline coordinations.
Keywords: molecular dynamics, metglass, nanocrystalline alloys, transition metals, Rare Earth elements, clusters, long order, intermediate order, short order.
FORCES IN ELECTRON-NUCLEAR SYSTEMS – page 312.
V.I. Repchenkov, A.A. Nalichayev, K.P. Deshkevich
Abstract: In present work a mechanism of occurrence returning forces in electron-nuclear systems is described.
Keywords: electron-nuclear systems, equilibrium, returning forces, chemical bonds, atom-atom potentials.
RELIABILITY ASSESSMENT OF COMPOSITION TiNiHf – page 315.
P.O. Rusinov, Zh.M. Blednova
Abstract: Based on comprehensive metalophysical researches, new information was obtained about the composition within the nanoscale surface-modified layer, its structural and mechanical properties. On the basis of experimental data on X-ray analysis of the alloy TiNiHf, the energy consumption, the theoretical strength have been calculated.
Keywords: shape memory effect, mechanical activation, durability, theoretical strength, energy capacity.
PHOTOINDUCED PROCESSES IN THIN FILM-PHOTOCATALYSTS BASED ON OXIDE NANOHETEROSTRUCTURES – page 323.
L.Yu. Sadovskaya, T.V. Sviridova, D.V. Sviridov
Abstract: The possibility of synthesis of hybrid oxide photocatalytic systems with prolonged oxidation activity has been demonstrated by combining nanodispersed titanium particles with
redox-active molybdenum trioxide capable to store photoproduced charges.
Keywords: nanodispersed titanium dioxide, photochemistry, molybdenum trioxide, solvothermal synthesis, hybrid oxide photocatalysts, oxidation activity, UV irradiation.
ON THE PROBLEM OF THE PHASE DIAGRAMM FOR BINARY METAL NANOPARTICLES – page 330.
V.M. Samsonov, S.A. Vasilyev, A.G. Bembel, A.Yu. Kartoshkin
Abstract: The problem of the phase diagram for binary metal nanoparticles is stated and discussed. From this viewpoint, three size ranges of metal nanoparticles are distinguished: small metal nanoparticles less than 1-2 nm in size, for which concepts of the thermodynamic phase and phase transitions seem to fail completely, mesoscopic particles containing from several hundreds to several thousands of atoms and big particles of order of 100 nm in size, for which the size dependence of the surface energy is not principal. As a pattern of phase diagrams for mesoscopic particles, phase diagram for binary Au – Ag particles consisting of 2000 atoms has been obtained using molecular dynamics results and discussed. It has been found that the form of this phase diagram principally differs from that for the corresponding balk phases. The melting-crystallization hysteresis is treated as the main reason of such a divergence.
Keywords: phase diagram, binary nanoparticles Au – Ag, melting-crystallization hysteresis.
EVALUATION OF THE PROPORTIONALITY COEFFICIENT IN THE RUSANOV’S FORMULA FOR THE SURFACE TENSION USING KINETIC DATA ON RATES OF EVAPORATION OF NANOPARTICLES AND SHRINGKAGE OF VACANCY PORES – page 337.
N.Yu. Sdobnyakov, V.M. Samsonov, A.N. Bazulev, D.A. Novozhilova
Abstract: Using experimental data on the evaporation rate of small metal particles (silver, lead) and of the rate of shrinkage of vacancy pores (aluminum), intervals of the reliability are estimated for the proportionality coefficient in Rusanov’s linear dependence σ = Kr between the surface tension σ and the particle radius r. The results obtained are compared to earlier estimations by E.N. Vitol (1992) and other authors.
Keywords: Rusanov`s formula, surface tension, proportionality coefficient, evaporation rate, shrinkage of vacancy pores rate.
ON SIZE DEPENDENCES OF MELTING AND CRYSTALLIZATION ENTROPIES OF COPPER NANOPARTICLES – page 345.
N.Yu. Sdobnyakov, A.D. Veselov, P.M. Ershov, D.N. Sokolov, V.M. Samsonov, S.A. Vasilyev, V.S. Myasnichenko
Abstract: Using molecular dynamics (MD) and Monte Carlo (MC) simulation results on melting and crystallization of copper nanoparticles (temperatures and heats of phase transitions), size dependences of the melting and crystallization entropies were obtained and analyzed. Besides, a theoretical approach to the estimation of size dependence of melting and crystallization entropies was developed. It has been found that the size dependence of the melting entropy is more pronounced than that for the crystallization entropy. The conclusion was confirmed using two alternative methods of computer simulation (MD and MC).
Keywords: size dependence, melting and crystallization entropies, copper nanoparticles.
RELIEF DYNAMIC HOLOGRAMS IN THIN LAYERED MEDIUM WITH THERMOINDUCED PHASE TRANSITION – page 354.
S.R. Simakov, V.I. Ivanov
Abstract: Theoretical analysis of the efficiency of reflective relief hologram in thin media layer was executed. The relief nonlinearity coefficient caused by phase transition in thin media layer is analyzed on the basis of two-dimensional thermal task.
Keywords: dynamic holography, relief holograms, phase transition.
SURFACE MODIFICATION OF POLYSTYRENE THIN FILMS BY RADIO FREQUENCY NITROGEN PLASMA TREATMENT – page 359.
A.V. Smirnov, I.V. Sinev, I.D. Osyko
Abstract: The effect of treatment by the radio frequency (RF) nitrogen plasma of magnetron discharge on surface modification of polymer thin films was studied. The dependence of surface roughness and wettability on the plasma exposure time was investigated. It was shown that increasing the treatment time in the nitrogen plasma in the range of 0 – 20 seconds reduces wetting angle from 110° to 69°. Also, it was observed a non-monotonic dependence of the roughness index in the range of 1,54 – 18,9nm.
Keywords: plasma treatment, surface modification, polystyrene.
THE FEATURES OF BEHAVIOR OF THERMODYNAMIC AND STRUCTURAL CHARCTERISTICS OF COBALT NANOPARTICLES WITH «MAGIC» NUMBER OF ATOMS – page 363.
D.N. Sokolov, V.S. Myasnechenko, A.P. Andriychuk, V.V. Kulagin, N.Yu. Sdobnyakov
Abstract: Investigations of thermodynamic and structural characteristics of cobalt nanoclusters in the process of phase transition melting/crystallization with the goal to identify characteristics of their behavior typical for the clusters with the «magic» number of atoms. The melting point of nanoclusters was determined using the temperature dependence of the specific internal energy of nanoclusters.
Keywords: cobalt nanoclusters, phase transition, melting temperature, «magic» numbers.
RESEARCH OF STRUCTURE AND OPTICAL PROPERTIES OF LiNbO3 : Zn CRYSTALS – page 372.
N.A. Teplyakova, N.V. Sidorov, А.А. Yanichev, M.N. Palatnikov, L.A. Alyoshina, A.V. Kadetova
Abstract: Structure of LiNbO3 : Zn crystals was shown to be more ordered in concentration range ~ 3,95 ÷ 4,54 mol. % ZnO. Rise of dopant concentration to 5,84 mol. % leads to sharp increase of 876 cm-1 Raman band. This band is connected with changes in B – O – B (B = Nb, Li, Zn) bridge. Change of ion contribution to this band explains smooth rise in electro-optical coefficients at 3 – 7,6 mol. % ZnO in LiNbO3.
Keywords: single crystal, lithium niobate, doping, zinc cations, Raman spectroscopy, full-profile XRD, stretching modes.
ASSESSMENT OF THE STABILITY OF THE PALLADIUM-PLATINUM NANOPARTICLES OF VARIOUS TYPES OF STRUCTURE – page 379.
I.V. Chepkasov
Abstract: Using molecular dynamics method and the EAM potential, the thermal stability was investigated of the structure of Pt – Pd nanoparticles (D = 1,5 – 4,0 nm) of various types (binary alloy, core-shell, Janus) and with different percentages of platinum atoms. It is shown that under the growth of the nanoparticles size, the thermal stability of their structure increased, and at the D = 3,0 nm transitions to other isomorphic modification were not found.
Keywords: nanoparticles, platinum, palladium, EAM-potential, structure.
THE ANALYSIS OF THE THERMAL STABILITY OF Cu@Si NANOPARTICLES – page 387.
I.V. Chepkasov
Abstract: In the work using molecular dynamics simulations, the parameters of the thermal stability of the composite nanoparticles Cu@Si of different size and structure were calculated. It was found that the thermal point of abrupt change in potential energy of the investigated particles. The relationship of these changes with the violation of the nanocomposite structure is discussed. It was concluded that with increasing the temperature the diffusion of copper atoms to the surface results in a reversal of the particle structure.
Keywords: nanoparticles, core-shell, MEAM- potential, thermal stability.
STUDY OF CuAu NANOPARTICLES CONDENSATION FROM THE GAS PHASE. MD-SIMULATION – page 393.
I.V. Chepkasov
Abstract: The condensation of the gas medium consisting of 85 000 Cu and Au atoms was studied by molecular dynamics using the tight-binding potential. The evolution of the modelled system while cooling with various constant rates shows a clear relationship between the cooling rate of the system, the final temperature, concentration, size and structure of the synthesized clusters.
Keywords: computer simulation, nanoparticles CuAu, structure, shape, the gas phase.
STRUCTURAL PROPERTIES OF FERROELECTRIC POLYMERS (PVDF AND PTFE-42, SKF-32) AND COMPOSITES BASED ON IT – page 398.
R.I. Shakirzyanov, V.A. Astakhov, A.T. Morchenko, N.P. Bessonova, N.A. Shmakova, A.E. Afonkin, A.A. Korlukov, M.I. Buzin
Abstract: Some structural properties of ferroelectric polymer thin film samples of polyvinylidenefluoride, its copolymers (F-42, SKF-32) and its composites with ferrite powder were investigated. Infrared spectroscopy shows that film of SKF-32 does not have areas of VDF chains with long sequences in planar zigzag conformation. Evaluation of the effect of the ferrite particles on the polymer matrix shows, that filler promotes the formation of new crystallization nuclei in the polymer F-42 and PVDF (F2M). By using the methods of polarizing optical microscopy and laser light scattering it was revealed that the PVDF film obtained by hot pressing, have spherilitic supramolecular structure, whereas the samples prepared by precipitation from solution, do not have such structure.
Keywords: ferroelectric polymers, ferrites, composites.
STRUCTURE OF RAPIDLY SOLIDIFIED BISMUTH-TIN ALLOYS ADDITIONAL DOPING WITH INDIUM – page 404.
V.G. Shepelevich
Abstract: Results of investigation of phase composition and microstructure of rapidly solidified doping with indium bismuth-tin alloys are presented. Doping with indium causes the consolidation of the structure.
Keywords: high-speed crystallization, foil, specific surface of interphase boundary, tin, bismuth, indium.
ELECTROCHEMICAL METHODS FOR NANOSTRUCTURED THICK-LAYER Al2O3-COATING FORMATION FOR EFFECTIVE HEAT-CONDUCTING BASES – page 410.
D.L. Shimanovich
Abstract: The aluminium alloys electrochemical anodizing methods in one-component and two-component pore-forming electrolytes for the manufacturing of large-format alumina bases (including the heatsink systems) with one-sided and two-sided dielectric anode alumina coatings are optimized. The comparative analysis of the dependences of thickness and nanostructured anode Al2O3 films formation rate on the anodizing electrochemical modes and the preliminary temperature Al treatment is demonstrated.
Keywords: aluminum, electrochemical anodization, porous anode alumina, nanostructured material, anodization rate, base plate, heatsink system.
ANALYSIS OF FUSION AND CRYSTALLIZATION PROCESSES OF CRYSTALLINE HYDRATES ON BASIS OF FUSIBILITY THERMOGRAMS – 5 page.
V.D. Aleksandrov, Sh.K. Amerkhanova, V.A. Postnikov, A.Yu. Sobolev, O.V. Sobol
Abstract: On basis of heating and cooling thermograms analysis of fusion, dehydration, hydration and solidification processes of crystalline hydrates Na2S2O3•5H2O, Na2SO4•10H2O, Na2SO3•7H2O, Na2CO3•10H2O and Na2CH3COO•3H2O is given. Hydrates structurization schemes in the liquid state are offered. The interpretation of different crystallization types reasons (quasiequilibrium and nonequilibrium-explosive) is given. Various stages of crystallization at EC and NEEC are considered. The equations for enthalpies of nucleation, coagulation and an isothermalpre-crystallization are obtained.
Keywords: crystalline hydrates, solutions, crystallization of water, fusion, dehydration, hydration, overcooling, equilibrium and nonequilibrium crystallization, nucleation, coagulation, enthalpy.
NOVEL ORGANIC HEAT STORAGE MATERIALS BASED ON PHASE TRANSFORMATIONS – 16 page.
V.D. Aleksandrov, Sh.K. Amerhanova, O.A. Pokyntelytsia, A.Ye. Pokyntelytsia
Abstract: In present paper the possibility of implementation of a number of the aromatic substances and their mixtures as promising heat storage materials (HSMs) is analyzed. The studied samples were not included in the nomenclature of HSMs. Physical and chemical parameters of the hydrocarbons as well as the eutectic compositions of their mixtures are presented. The fusibility thermograms indicate the applicability of these substances and their mixtures as HSMs.
Keywords: heat storage materials, aromatic hydrocarbons, phase transformations, fusibility thermograms, eutectic alloys.
STUDY OF THE STABILITY OF AQUEOUS COLLOIDS BASED ON HARD-MAGNETIC STRONTIUM HEXAFERRITE NANOPARTICLES – 22 page.
E.O. Anokhin, L.A. Trusov, A.V. Vasiliev, E.A. Gorbachev, A.A. Eliseev, P.E. Kazin
Abstract: Herein we investigate the stability of strontium hexaferrite aqueous colloid by dynamic light scattering method in relation to solution acidity and electrolyte concentration.
Keywords: strontium hexaferrite, magnetic nanoparticles, magnetic fluids, colloids, colloidal stability.
SCANNING TUNNELING MICROSCOPY FOR THE NANOCOATING «SILVER/MICA»: RELIEF MORPHOLOGY AND ELECTRICAL CHARACTERISTICS – 31 page.
A.S. Antonov, O.V. Mikhailova (Zonova), N.Yu. Sdobnyakov, D.N. Sokolov, D.V. Ivanov
Abstract: As a result of our investigation, it was shown that of thin metal films on dielectric substrates allow to prepare samples that satisfy the requirements for working the scanning probe microscope in scanning tunneling microscope mode. This preserves the information about the features of the surface morphology of individual objects smaller than 100 nm. The sample «silver/mica» is considered as an example. Linear dimensions of individual surface objects (peaks and troughs) have been determined including the factors affecting the formation of relief pattern. Certain parts of the profile and surface have been investigated for the presence of fractal structures. It was found that the system of clusters on the surface of the investigated sample is fractal. In addition, for each cluster dependence of the natural logarithm of the number of particles on the natural logarithm of the particle size of the cluster is approximately linear, that allows to consider the structure of individual clusters and the surface profile as fractal. The investigation of the current-voltage characteristics of the metal-metal silver sample with tungsten tip proves the experimental results demonstrating the need for careful analysis of the parameters affecting the tunneling current to receive extract information about the electronic structure of the sample.
Keywords: scanning tunneling microscopy, silver, mica, fractal dimension, profile, surface, current-voltage characteristic, the thermal expansion of the tip.
DEPENDENCE OF INTERFACIAL ENERGY OF ALKALI METALS BOUNDING TO HEXANE ON ORIENTATION AND ATOMIC NUMBER OF ELEMENT – 47 page.
A.M. Apekov, I.G. Shebzukhova
Abstract: The method to calculate the interfacial energy on the boundary with non-polar organic liquids has been developed within the electron-statistical theory. The dependence of interfacial energy of faces of alkali metal crystals bounding to hexane on the atomic number of the element has been obtained. The anisotropy of the interfacial energy has been found.
Keywords: interfacial energy, lithium, sodium, potassium, rubidium, cesium, atomic number, electron-statistical theory.
ANISOTROPY OF WORK FUNCTION OF BCC 4D AND 5D METALS
L.P. Aref`eva, I.G. Shebzuhova
Abstract: On the bases of modified electron-statistical method, we have proposed the method of calculation of the work function’s anisotropy of metallic monocrystals. The work function and surface energy had been calculated for closepacked faces of allotropy phases of 4d– and 5d– metals with bcc structure. We had demonstrated that this method gives the results, which correlate with experimental data for polycrystals.
Keywords: anisotropy, work function, surface energy, transition metals, temperature dependence, allotropy phases.
THE CONTACT MELTING OF COPPER WITH ALUMINUM – 59 page.
A.A. Ahkubekov, P.K. Korotkov, A.R. Manukyants, M.Kh. Ponegev, V.A. Sozaev
Abstract: The contact melting of copper (in shape of a cylinder) and aluminum (in shape of a cone) has been carried out. The needle-like structures of sizes 250-270 microns in length and 10-11 microns in width as well as the dendritic arrangements of ~2,6 millimeters length have been revealed within the formed contact layer. The thin film (of thickness about 30 microns) has been observed straight of the copper which is, obviously, the phase Al4Cu9 the presence of which the state diagram indicates.
Keywords: contact melting, dendritic arrangements, metals.
SIMULATION OF SYNTHESIS AND COLLAPSE OF AMPHIPHILIC COPOLYMER WITH THE NUCLEATING HYDROPHOBIC BLOCK – 63 page.
P.O. Baburkin
Abstract: Results of coarse grained simulations of synthesis of amphiphilic AB copolymers with the aim to obtain compact and stable core-shell nanostructures are presented. It is shown that the target nanostructures are formed at an optimal monomer ratio in the reaction mixture. These results can be used as the reference point in a laboratory synthesis.
Keywords: Coarse-grained computer simulation, amphiphilic copolymers, protein-like polymers, enzyme.
INVESTIGATION OF ALUMINUM NITRIDE FORMATION PROCESSES IN PLASMA WHEN THE ALUMINUM ALLOY D16T IS SUBJECTED TO THE EFFECT OF DOUBLE LASER PULSES IN THE AIR – 70 page.
Bazzal Khodor, Fadaijan Аhmad Reza, Е.S. Voropay, А.P. Zajogin
Abstract: The effect exerted by defocusing of double laser pulses on the formation of the component and charge composition in the surface laser plasma has been studied by the laser spark spectrometry (LSS) method. The possibility to increase the portion of variously charged aluminum ions in the surface laser plasma and also of AlN clusters when the target was subjected to a series of successive double laser pulses has been demonstrated.
Keywords: AlN radicals, pulsed laser deposition, surface laser plasma, laser spark spectrometry, multiply charged ions, double laser pulses.
MOLECULAR DYNAMICS STUDY OF THE KINETICS OF CuAu CLUSTERS FORMATION IN THE CONDENSATION PROCESS FROM HIGH TEMPERATURE GASEOUS PHASE – 76 page.
V.S. Baidishev, Yu.Ya. Gafner, E.A. Kartavych
Abstract: Condensation of copper-gold clusters from gas phase at high temperatures was simulated using molecular dynamics. It is shown that the initial density of the metal vapor has a significant influence on the kinetics of cluster structures formation.
Keywords: computer simulation, molecular dynamics, condensation, nanoclusters.
THE STRUCTURE SYSTEM ANALYSIS APPLICATION FOR OPTIMIZATION OF STILL-WELDING REGIMES – 83 page.
B.K. Barakhtin, M.A. Vysockaya
Abstract: The structure investigation results on still-welding zones of aluminum-magnesium group’s alloys are presented. The structure changing at still-welding regimes was exposed by metallographic and system analysis methods.
Keywords: still-welding, microstructure, plastic deforming, tribolodgy, fractal analysis.
CREATING A HEAT SINK METAL-COMPOSITE MATERIAL – 97 page.
V.V. Batin, N.A. Pan’kin
Abstract: The results are presented on the creation of a composite material for heat sink substrate of semiconductor crystals of power electronics products with a given set of physical and mechanical properties.
Keywords: metal matrix composite material, melting temperature, the thermal expansion coefficient.
ON PROSPECTS OF PRODUCTION AND APPLICATION OF AMORPHOUS CHALCOGENIDE FILMS GeSbTe-101 page.
S.A. Baturkin
Abstract: This work may be treated as a review of papers devoted to the structural transition from amorphous to crystalline state of chalcogenide films GeSbTe and the effect of memory related to the transition in question, i.e. to the keeping of the conductive state of the film in the absence of the external voltage for a long time. Besides, a review is presented of the result of author related to the improvement of the polylayer film technology.
Keywords: chalcogenide films, compounds germanium-antimony-tellurium, memory effect, polylayer films, technology.
STRUCTURE OF SP2+SP3 HYBRID PHASES RESULTING FROM CARBON NANOTUBES -111 page.
E.A. Belenkov, M.I. Tingaev
Abstract: A theoretical analysis of the possible structure of new carbon phases consisting of carbon atoms in the three- and four-coordinated states resulting by cross-linking bundles of zigzag nanotubes is performed. The calculation of the structures of sp2+sp3 hybrid phases was performed using density functional theory (DFT). As a result of the simulation revealed that there are 14 new hybrid carbon phases. Structural parameters, density of states and bandstructures for all phases were calculated.
Keywords: carbon, diamond, graphene, crystal structure, carbon nanotubes, hybrid carbon phases, computer simulation.
STRUCTURE AND ELECTRONIC PROPERTIES OF Α-GRAPHYNE, WHICH CAN BE OBTAINED BY L4-8 GRAPHENE -117 page.
T.E. Belenkova, V.M. Chernov
Abstract: Using the density functional theory method, we calculated the crystalline structure and electronic properties of new structural modification of α- graphyne, which can be obtained by L4-8 graphene.
Keywords: carbon, graphene, hybridization, electronic structure, modeling.
INFLUENCE OF TEMPERATURE TREATMENT ON THE STRUCTURE AND COMPOSITION OF NANOSIZED ZnO, OBTAINED BY SOL-GEL METHOD – 123 page.
A.V. Blinov, A.A. Kravtsov, M.A. Jasnaja, A.Ju. Rusanov, E.V. Momot
Abstract: Synthesis of nano-sized zinc oxide was performed by sol-gel method. The structure of the nano-sized ZnO was studied at the gel stage. The effect of calcination temperature on ZnO nanoparticles size and polydispersity of the samples and their phase composition and structure was investigated. IR spectroscopy of the samples of nano-sized zinc oxide was carried out.
Keywords: ZnO nanoparticles, sol-gel method, TEM, XRD, IR spectroscopy.
EVALUATION OF BIOACTIVE COATING DURABILITY ON THE TITANIUM OF VARIOUS POROSITY – 130 page.
E.A. Bogdanova, V.M. Skachkov, A.G. Shirokova, N.A. Sabirzyanov
Abstract: The ways of bioactive composite creation on porous titanium substrate are considered. Strength and adhesive properties of hydroxyapatite on the titanium are studied. The methods of determining suitable for evaluation of metal and non-metallic components adhesion in the composite are offered.
Keywords: biocomposites, functional bioactive coating, strength properties, hydroxyapatite (HAP), porous titanium.
THE INFLUENCE OF THE MAGNETIC FIELD ON THE LUBRICATING PROPERTIES OF THE NANOSTRUCTURED MAGNETIC OIL – 137 page.
A.N. Bolotov, G.B. Burdo, V.V. Novikov, O.O. Novikova
Abstract: We researched the effect of the magnetic field on the structure and properties of the lubricants. The magnetotribological effect was discovered. It was established that wear-preventive properties of the oil degrade because of the uniform fields influence.
Keywords: magnetic oil, disperse medium, nanodispersed particles, friction, deterioration, magnetotribological effect.
RESEARCH OF THE DEPENDENCE OF SURFACE PHYSICAL PROPERTIES FROM THE FRACTAL DIMENSION – 142 page.
Yu.V. Brylkin, A.L. Kusov
Abstract: On the basis of images obtained using a scanning tunneling microscope, it is shown that the fractal dimension may be a universal feature in the study of surfaces development at a level close to the nanometer. Also the dependence of the material catalytic properties from the surface morphology is revealed.
Keywords: fractal, scanning tunneling microscopy, surface topology, catalytic activity.
SPECTRAL AND VOLTAMMETRIC CHARACTERISTICS OF NANOSTRUCTURED ZnO – 150 page.
L.Yu. Buldakova, O.I. Gyrdasova, V.N. Krasil’nikov, I.V. Baklanova, M.Yu. Yanchenko
Abstract: Nanostructured ZnO was obtained by using zinc salts with an organic ligand as a precursors. It is shown that ZnO synthesized from Zn(OCH2OCHCH2O) possessed the best optical, voltammetric and photocatalytic characteristics.
Keywords: Zinc oxide, nanostructures, synthesis, precursors, morphology, microstructure, defects of structure, dynamics of electron excitations, photocatalysts.
STUDY ON THE POSSIBILITY OF DOPING WITH NITROGEN AND SILICON CAVITATION NANODIAMONDS – 158 page.
S.А. Voropaev, N.V. Dushenko, A.S. Aronin, V.M. Shkinev, E.M. Galimov
Abstract: Colour centers in nanodiamonds by experiments with organic liquids under cavitation are obtained. The features of doping with nitrogen and silicon at their occurrence in a crystalline structure of carbon nanoparticles are considered.
Keywords: diamond, impurity, photoluminescence, cavitation, nitrogen, silicon.
RESEARCH OF CLUSTER FORMATION IN CRYSTALS OF LITHIUM NIOBATE BY COMPUTER MODELING METHOD – 165 page.
V.M. Voskresensky, O.R. Starodub, N.V. Sidorov, M.N. Palatnikov
Abstract: A study of the processes occurring during the formation of the energy equilibrium oxygen octahedral clusters of lithium niobate crystal is carried out. It is shown that there is energetically favorable size of a cluster, and due to the loss of electrical neutrality cluster of stoichiometric composition cannot exist. The most favorable energy corresponds to the cluster with a ratio of Li/Nb≈0,945, which is close to the ratio of lithium to niobium in congruent crystal.
Keywords: lithium niobate, cluster, simulation.
CRYSTALLINE STRUCTURE AND PROPERTIES OF LA7 DIAMOND-LIKE PHASE -174 page.
V.A. Greshnyakov, E.A. Belenkov
Abstract: Using the density functional theory method, we calculated the crystalline structure and properties of LA7 diamond-like phase, which can be obtained by linking of graphene layers.
Keywords: diamond, polymorphism, diamond-like phase, modeling, crystal structure, electronic density of states, bulk modulus, hardness, X-ray pattern.
SEM STUDY OF THE MICROSTRUCTURE OF BIOCOMPOSITES BASED ON HIGHLY POROUS HONEYCOMB MATERIALS – 179 page.
I.G. Grigorov, A.G. Shirokova, E.A. Bogdanova, V.M. Skachkov, S.V. Borisov, N.A. Sabirzyanov
Abstract: The paper is devoted to the study of the morphology and surface topography of the synthesized biocomposites, intended for creation of implants by scanning electron microscopy. Produced by ion-plasma spraying NiTi was selected as the metal substrate. Bioactive coating formed from an aqueous slurry of hydroxyapatite. The effectiveness of the proposed in the work methods of the coating was evaluated by constructing 2D- and 3D-images of the surface.
Keywords: implant, biocomposites, Titanium Nickelide (NiTi), hydroxyapatite (HAP), 2D-, 3D-image, scanning electron microscopy.
EFFECT OF LATERAL INTERACTION ON THE IMPURITY SEGREGATION IN FILMS – 186 page.
I.М. Davydova, T.N. Мelnik, V.М. Yurchenko
Abstract: Theoretical analysis of the effect of lateral interaction on the kinetics and the result of segregation in multi-layered films has been carried out. The ranges of the parameters (the initial impurity concentration, the temperature and the film thickness) are found where the effect substantially modifies the process. As compared to the impurity segregation in bulk samples, the established range of the parameters is narrower because of the limited reserve of the impurity within a thin layer.
Keywords: segregation, lateral interaction, Fowler isotherm
QUANTUM CHEMICAL DESIGNING OF ENDOHEDRAL CONTAINING INDIUM DERIVATIVES OF BUCKMINSTERFULLERENE C60 AND C70 FOR DEVELOPMENT RADIONUCLIDE NANOSIZED AGENTS THAT DESTROY A TUMOR -193 page.
Е.А. Dikusar, А.L. Pushkarchuk, V.I. Potkin, S.Ya. Kilin, А.G. Soldatov, S.А. Kuten, A.N. Khmelevskiy, L.F. Babichev
Abstract: In this work the simulation was performed of the electronic structure and geometry of endohedral containing Indium derivatives of buckminsterfullerene C60 and C70 and monoester – a heterocyclic carboxylic acid derivative.
Keywords: electronic structure simulation, endohedral containing Indium derivatives of buckminsterfullerene, agents that destroy a tumor.
INVESTIGATION OF INFLUENCE OF SCANNING STEP ON IR-TRANMISSION SPECTRA OF NITRIDE ALUMINUM FILMS – 208 page
O.S. Zurkhaeva, D.S. Zurkhaev, L.P. Aref`eva
Abstract: The influence of scanning step on IR-tranmission spectra of nitride aluminum films had been study. The optimal conditions of scanning, when the ratio «signal-noise» has minimum, had been determined.
Keywords: IR-spectroscopy, thin films, semiconductors.
A HOLOGRAPHIC SENSITIVITY OF THE NANOHETEROGENEOUS MEDIUM WITH A BLURRED PHASE TRANSITION – 216 page.
V.I. Ivanov, S.R. Simakov
Abstract: A holographic sensitivity of the nanoheterogeneous medium with a blurred metal-semiconductor phase transition is analyzed. It is shown that the maximum value of the energy sensitivity is achieved for the final width of the phase transition.
Keywords: holographic sensitivity, metal-semiconductor phase transition, vanadium dioxide.
NONEQUILIBRIUM CURRENTS IN THIN-LAYER METAL-FERROELECTRIC-METAL SANDWICH STRUCTURE – 220 page
V.I. Ivanov
Abstract: A thermoinduced nonequilibrium current is described in thin metal-ferroelectric-metal sandwich system. The thermal response value increases dramatically when one reduces the thickness of the crystal. Possible mechanisms of the phenomenon are discussed.
Keywords: thermovoltaic effect, lithium niobate, metal-ferroelectric-metal sandwiched structure.
MODIFICATION OF SURFACE LAYER OF HYPEREUTECTIC SILUMIN BY HIGH-INTENSITY PULSED ELECTRON BEAM – 225 page.
Yu.F. Ivanov, A.P. Laskovnev, A.D. Teresov, N.N. Cherenda, V.V. Uglov, E.A. Petrikova, M.V. Astashinskaya, N.N. Koval
Abstract: The results of the analysis of the elemental and phase composition, the defect substructure, strength and tribological characteristics of the hypereutectic composition silumin in the molten state and after irradiation with high-intensity electron beam are presented. The formation of the modified surface layer with thickness of up to 1000 µm, having increased strength and tribological characteristics was demonstrated as a result of irradiation.
Keywords: hypereutectic composition silumin; high intensity pulsed electron beam, structure, properties.
STRUCTURAL PHASE STATES OF Cu-Zn-Al ALLOY POWDERS PRODUCED BY HF-PLASMA-CHEMICAL DENITRATION -232 page.
Yu.F. Ivanov, A.A. Klopotov, N.V. Dedov, N.A. Popova
Abstract: The paper presents a study of Cu-Zn-Al alloy that is proved to be a multiphase material. In the equilibrium state, α– phase (fcc crystal lattice) and β– phase (simple centered cubic lattice) can be formed in this alloy based on copper. It is shown that γ– phase can be formed due to the three-component alloy composition, and the different chemical composition of the Cu- based solid solution (Zn or Al alloys), the different concentrations of its second element result in the formation of a certain amount of α- and β-phases within the one type of the crystal lattice that differ in its parameter. The possibility of the alloy powder synthesis is shown using the plasma-chemical techniques that allows the formation of X-ray amorphous and nanocrystal structure. A variety of binary phases characterized by Zn and Al concentration in the Cu– based solid solution is described in this paper. The experimental results show that plasma-chemical synthesis of metal alloy powders is accompanied by decomposition of chemical elements. Powders of the triple composition were not observed.
Keywords: alloy; HF-plasma-chemical denitration, phase diagram, phase composition, structure.
THE INFLUENCE OF THIN FATTY ACID FILMS ON TRIBOLOGICAL PROPERTIES OF A DISCRETE CONTACT OF METAL SURFACES – 242 page.
V.V. Izmailov, A.F. Gusev, M.V. Novoselova
Abstract: The values of the coefficient of friction in a single ball–plane contact have been measured experimentally under small normal loads (0,5-5 mN). The contact parts are made of steel. The experiments have been carried out with thin fatty acid films layered on a flat contact part. The fatty acids have various molecular lengths. Experimentally obtained values of the specific force of friction at a microscale level are higher than similar values known from literature and obtained in experiments at a macroscale level.
Keywords: friction coefficient, specific force of friction, fatty acids.
PROPERTIES OF ZnO CERAMICS SINTERED FROM NANOPOWDERS ZnO-Zn, OBTAINED PULSED ELECTRON EVAPORATION – 249 page.
V.G. Il`ves, S.Yu. Sokovnin, V.R. Khrustov, S.V.Zayats, S.V. Pryanichnikov, M.G. Zuev
Abstract: We investigated the properties of ceramic ZnO, sintered from nanopowders ZnO-Zn, obtained by a pulsed electron evaporation of diverse targets. Behavior of shrinkage curves of nano ZnO-Zn depends on the history of their production. Evolution of properties of nanoparticles ZnO-Zn during annealing in the air were traced via XRD and pulsed cathodoluminescence.
Keywords: pulsed electron beam, nanopowders ZnO-Zn, ceramic ZnO-Zn, cathodoluminescence ceramic ZnO-Zn.
THE CALCULATION OF SURFACE THERMODINAMICAL PARAMETERS FOR BINARY ALLOYS OF METALLIC SYSTEM – 257 page.
Z.Kh. Kalazhokov, Zaur Kh. Kalazhokov, Kh.Kh. Kalazhokov, N.S. Reutskaya, Z.V. Kardanova, E.Kh. Sherieva
Abstract: The methods for estimation of adsorption and surface concentration of binary alloys components by the particle exchange parameter between surface and bulk phases of binary alloys are suggested. It is shown the suggested methods allow to exclude some tradition calculation methods deficiency of these surface parameters.
Keywords: surface tension, adsorption, surface composition.
THE ELECTRO-PHYSICAL PROPERTIES OF A SPECIAL GLASS ELECTRONIC ENGINEERINGS – 263 page.
A.M. Karmokov, O.A. Molokanov, Z.V. Shomakhov
Abstract: The regularities of changes in the electrical properties of glasses S87-2, S78-4, S78-5 used in vacuum electronics. A correlation between structural change and electrical conductivity is proposed. A comparative analysis was carried out of the influence of an electric current on the formation of a new phase and the time to reach the phase equilibrium in the glass.
Keywords: microchannel plate, the emission layer, lead-silicate glass, barium borate glass, conductivity, isothermal annealing, elektromassoperenos, phase equilibria.
SYSTEMATIC COMPARISON OF THE SOLUBILITY AND SUPERSOLUBILITY ON THE BASE OF THE SALT DIMENSIONAL FACTORS – 270 page.
B.I. Kidyarov
Abstract: A comparison of the solubility line and the metastability boundary in aqueous solutions have been carried out on the basis of the salt dimensional factors. It is shown that these solution parameters and other ones are changed non-monotonically due to the ionic radii increasing for iso-valence salt groups. It is observed the salt taxonomy on the characteristic subgroups of ideal and non-ideal electrolytes.
Keywords: ion dimension, mechanism of the nano-stage nucleation, solution supercooling, dimensional dependence of the salt solubility and supersolubility.
A NONLINEAR OPTICAL DIAGNOSTICS OF NANO-LIQUIDES – 280 page
S.I. Kirjushina, A.V. Mjagotin
Abstract: Nonlinear lens technique is widely used to study nonlinear media and optical diagnostics of materials. In the dispersed environment there is a specific mechanism of optical nonlinearity based on the redistribution of the dispersed particle concentration in the light gradient field. In this paper a theoretical analysis of the light-induced mass transfer in the dispersed liquid medium in the Gaussian beam field was carried out.
Keywords: radiation self-action, electrostriction, dispersion medium.
EFFECT OF ELECTRIC FIELD ON PROCESSES IN SEMICONDUCTOR NaAuy FILM – 284 page.
M.V. Knatko, M.N. Lapushkin
Abstract: The processes in semiconductor film NaAuy under the influence of an external electric field are studied. The model based on the properties of hole and electron conductivity of the semiconductor was suggested.
Keywords: adsorption, alkali metals, gold, intermetallic compounds, thermal desorption of atoms and ions, surface ionization.
METALS COALESCENCE AS A MECHANISM FOR NANOSOLDERING: SEARCHING STABLE CONFIGURATIONS – 292 page.
A.Yu. Kolosov, D.N. Sokolov, N.Yu. Sdobnyakov, P.V. Komarov, S.S. Bogdanov, A.A. Bogatov
Abstract: The simulation of the creating gold nanoscale contacts between tracks of nanoscale buses for different system configurations by Monte-Carlo method was carried out. The interaction between nanoparticles was described by many-body Gupta potential. The optimum parameters for creating nanoscale contacts between tracks of nanoscale buses have been determined. The final stable structure of nanoscale contacts has been analyzed.
Keywords: nanoscale contact, nanosoldering, gold and silver nanoparticles, coalescence, Monte-Carlo method, Gupta potential, stability.
THE DEVELOPMENT OF CORSEGRAINED MODEL OF ALUMINOSILICATE HALLOYSITE NANOTUBES – 302 page.
P.V. Komarov, V.A. Ivanov
Abstract: The problems of constructing of large-scale model of composites based on polymers and aluminosilicate nanotubes have been considered.
Keywords: nanocomposite, nanoparticles, computer simulation.
WAVE NATURE OF THE SYNTHESIS REACTIONS OF DOPED CALCIUM CARBONATE- PHOSPHATES AS ACTIVE BIOMATERIAL FOR OSTEOGENESIS – 311 page.
L.F. Koroleva
Abstract: A mechanism of the synthesis reactions of doped nanocrystalline calcium carbonate phosphates is considered, which has a wave nature and this result does not conflict with wave package. For the synthesis of doped calcium carbonate – phosphates motion the wave packet on the surface describes a set of consecutive zeroth order reactions.
Keywords: synthesis, mechanism, doping, carbonates, calcium phosphate, biomaterial, osteogenesis.
SCHEME FOR OBTAINING POLYMORPHOUS MODIFICATIONS OF GRAPHENE FROM CARBYNE CHAINS – 316 page.
A.E. Kochengin, E.A. Belenkov
Abstract: In the paper it was studied the structure of polymorphic modifications of graphene that can be obtained by cross-linking carbyne chains. It was found possibility of stable existence of new structural modifications of graphene.
Keywords: carbon, graphite, crystal structure, polymorphism, modeling.
ELECTROCHEMICAL DEPOSITION OF APATITE-POLYMER COATINGS ON TITANIUM SURFACE – 322 page.
V.K. Krut’ko, A.I. Kulak, O.N. Musskaya
Abstract: The apatite-polymer coatings on titanium substrates have been obtained using electrochemical deposition at constant current density of 20-80 mА/sm2 and room temperature in polyvinyl alcohol medium containing CaCl2–NH4H2PO4 electrolyte. The apatite-polymer coatings consist of brushite CaHPO4 × 2H2O, portlandite Ca(OH)2, amorphous calcium phosphate Ca3(PO4)2 × nH2O and hydroxyapatite Ca10(PO4)6(OH)2 depending on the deposition conditions.
Keywords: calcium phosphates, polyvinyl alcohol, electrochemical deposition, biocompatible coatings.
THE LIGHT INDUCED PSEUDO-PRISM METHOD IN NANOFLUID – 329 page.
V.I. Krylov, G.D. Ivanova, V.K. Khe
Abstract: The light induced pseudo-prism method is used to study nonlinear media and for optical diagnostics of materials. This paper proposes a way to create pseudo-prisms in the nanodispersive liquid through the light radiation pressure. As a result of the analytical solution of the light induced mass transport task it was obtained an expression for the deflection angle of the beam in a pseudo-prism.
Keywords: pseudo-prism method, light pressure, nanoliquids.
ELECTRON-STIMULATED DESORPTION OF CESIUM ATOMS ADSORBED ON GOLD SURFACE – 333 page.
Yu.A. Kuznetsov, M.N. Lapushkin
Abstract: The Cs atom electron-stimulated desorption (ESD) processes in Cs / CsAu / Au / W system have been studied. There have been shown that ESD processes occurred in the adlayer and in the nearest CsAu layer. The Cs atom ESD model in Cs / CsAu / Au / W system have been suggested. Nonmetallic (semiconductor) nature of CsxAuy compounds have been corroborated.
Keywords: electron-stimulated desorption, adsorption, alkali metals, gold, intermetallic compounds.
SIMULATION OF COORDINATION TRANSFORMATION AND ATOMIC DYNAMICS OF LOW DIMENSIONAL SYSTEMS REINFORCED Cu,Ru,Ru-Pd FILMS GRAPHENE -341 page.
E.D. Kurbanova, V.A. Polukhin, N.S. Mitrofanova, L.K. Rigmant
Abstract: In the presented article results of the molecular and dynamic modeling executed with use of many-body potentials. There has been carried out the analysis the thermoactivity of processes of a relaxation, diffusion and formation of the interface structures metal/graphene (is carried out by Me:Cu, Ru / G), their destruction, as analog of melting in low-dimensional systems.
Keywords: interface graphene/metal, parameter of incommensurability , corrugation defect.
THE TEMPERATURE DEPENDENCE OF THE SURFACE POTENTIAL OF p–TYPE MONOCRYSTALLINE SILICON – 350 page.
V.K. Lyuev, I.V. Lyuev
Abstract: The real surface of the p-type monocrystalline silicon was studied by the method of surface photo-EMF in the temperature range T = 289 – 473 K. A significant difference between the surface electronic states spectra obtained by heating and cooling the samples was found. Heating causes gas desorption and dissociation of water molecules in the surface layer, which reduces the surface potential on the order.
Keywords: photo-EMF, surface potential, p-type silicon.
INFLUENCE OF CHEMICAL TREATMENT AND THE TEMPERATURE ON THE SURFACE POTENTIAL OF THE MONOCRYSTALLINE SILICON KDB-10 (111) – 354 page.
V.K. Lyuev, I.V. Lyuev
Abstract: The spectra of the surface photo-EMF at temperatures of T = 289 – 473 K after processing in 10 % HF solution was investigated. It has been shown that the removal of an oxide layer reduces the concentration of surface electronic states located at the interface between silicon and surface film. In addition, the concentration of electron states in the films themselves changes. Processing in HF and subsequent washing with water reduces the concentration of traps, exciting nonequilibrium holes that deforms photomemory surface potential.
Keywords: monocrystalline silicon, surface potential, KDB-10.
ON THE DEPENDENCIES OF THE MELTING PARAMETERS VERSUS NUMBER OF ATOMS IN THE SILICON NANOCRYSTAL -358 page.
M.N. Magomedov
Abstract: Using the results of the paper [Zhao, J. Crystallization of silicon nanoclusters with inert gas temperature control / J. Zhao, V. Singh, P. Grammatikopoulos et al. // Physical Review B. – 2015. – V. 91. – I. 3. – P. 035419-1-035419-12] for calculation dependencies of the melting temperature Tm and the temperature of the beginning of crystallization TN on the number of atoms N in the silicon spherical nanocrystal the dependencies on N for the next melting parameters of silicon nanocrystal were obtained: the jump of the melting entropy, latent heat of melting, the slope of the melting line, the jumps of the volume and the surface energy.
Keywords: silicon, nanocrystal, melting, crystallization, heat of melting, jumps of properties at melting.
THE PROCESSES OF OBTAINING «COMPLEX» FILMS ON ALUMINUM – 367 page.
E.S. Markaryan
Abstract: In this paper, we consider the processes occurring during the formation of «complex» films on aluminum. We prepared them according to the characteristic of the growth kinetics of a continuous film in a matrix of porous anodic oxide. The geometric parameters of the nanostructured aluminum oxide were obtained in the process of reanodizing.
Keywords: anodic aluminum oxide, growth kinetics, «complex film», growth rate, porosity.
ON THE RELATIONSHIP BETWEEN STRUCTURE AND THERMAL STABILITY PROPERTIES OF COPPER CLUSTERS SIZE UP TO 100 ATOMS IN MOLECULAR-DYNAMICS SIMULATION – 378 page.
V.S. Myasnichenko, P.M. Ershov, N.Yu. Sdobnyakov, D.N. Sokolov
Abstract: In this paper a molecular-dynamics simulation of the structure and thermal stability of the copper clusters size up to 100 atoms has been carried out using many-body tight-binding potential. On the basis of the calculation of a local minimum energy for copper clusters it the «magic» nanoclusters can be found which are more stable. The size dependencies of the thermodynamic and structural characteristics for such clusters demonstrate specific behavior.
Keywords: molecular dynamics, tight-binding potential, copper nanoclusters, melting temperature, magic clusters.
EFFECT OF PLASMA TREATMENT ON THE SURFACE COMPOSITION OF SAPPHIRE – 391 page.
R.R. Nagaplezheva, A.M. Karmokov, B.N. Nagoev, M.M. Uyanaeva, V.K. Luev
Abstract: The plasma treatment of the surface of sapphire was performed. The composition of the sapphire surface before and after plasma treatment by X-ray photoelectron spectroscopy (XPS) is discussed.
Keywords: plasma, sapphire, XPS.
A GRAPH MODEL OF THE ENTHALPY OF FORMATION CALCULATION FOR ALKANES C11H24 WITH RESPECT OF MULTIPLE NON-VALENCE INTERACTIONS IN THREE ATOMS ALONG THE CHAIN – 391 page.
D.Yu. Nilov
Abstract: For the first time, a series of 159 C11H24 alkanes was proposed. A graph scheme containing 13 constants was obtained for evaluation of thermodynamic properties of branched saturated hydrocarbons.
Keywords: graph model, enthalpy of formation, multiple non-valence iteractions.
MODIFICATION OF LITHIUM TANTALATE CRYSTALS BY HIGH-TEMPERATURE TREATMENT OF VTE – 393 page.
M.N. Palatnikov, O.B. Shcherbina, N.V. Sidorov, S.V. Drogobuzhskaya
Abstract: The appearance of characteristical defects is demonstrated in lithium tantalate crystals treated by VTE (vapor transport equilibration) in lithium vapor. Raman spectra and mass spectrometry with inductively coupled plasma with laser ablation revealed existence of layers tens to hundreds microns thick with different Li / Ta ratio in modified lithium tantalate (LT VTE).
Keywords: lithium tantalate, VTE (vapor transport equilibration), mass spectrometry, inductively coupled plasma, laser ablation, Raman spectroscopy, Curie temperature, stoichiometry.
DISCRETE MODELING AT THE ATOMIC-MOLECULAR LEVEL OF MECHANICAL PROCESSES IN NANOCOMPOSITES – 400 page.
V.I. Repchenkov, Y.E. Nagorny, A.V. Akavity
Abstract: An analysis of the quadratic force fields at the interfaces in composites is presented.
Keywords: composite materials, carbon nanotubes, covalent bonds, non-bonded connection, interface, normal and tangential stresses.
MOLECULAR DYNAMICS MODEL OF THE TECHNOLOGY OF AMORPHOUS METAL FILMS PRODUCTION BY CONDENSATION ON THE COOLED SUBSTRATE – 407 page.
V.M. Samsonov, S.A. Vasilyev, A.G. Bembel
Abstract: A computer molecular dynamics program has been developed which makes it possible to imitate processes of thin film and epitaxial technologies. The program was approbated on the technology of amorphous metal films production by means of condensation on cooled substrate. It has been found that even at high cooling rates from 300 to 4 K (helium temperature) the silver atom beam forms amorphous films whereas the gold atom beam forms amorphous film under the same cooling conditions. The results obtained agree with the results of direct experiments demonstrating that bulk silver does not transfer into the amorphous state even at maximal available cooling rates.
Keywords: amorphous metal films, method of condensation on cooled substrate, molecular dynamics.
ON ALTERNATIVE APPROACHES TO DETERMINATION OF RADIUS AND OTHER GEOMETRIC CHARACTERISTICS OF NANOPARTICLES -413 page.
V.M. Samsonov
Abstract: The concept of the nanoparticle radius has been analysed and its relationship with the number of molecules (atoms) the particle consists of. A conclusion has been made that in most cases the radius of the equimolecular dividing surface can be used as an adequate measure of the particle size.
Keywords: nanoparticle, radius, equimolecular dividing surface, nanoclusters, Gibbs method of surface phases, Wigner-Seitz radius, gyroscopic radius.
ON BOUNDARY WETTING CONDITIONS FOR ROUGH SOLID SURFACE – 425 page.
M.V. Samsonov, V.M. Samsonov
Abstract: An equation has been obtained for the equilibrium contact angle on the rough surface. Contrary to the Wenzel-Deryagine equation, our equation takes into account the difference between the values of the surface tension of a rough surface and the corresponding smooth one. It has been shown that the conventional expression for the work of adhesion to the rough surface seems to be incorrect. An alternative expression was proposed and analyzed.
Keywords: equilibrium contact angle, rough surface, Wenzel-Deryagine equation, work of adhesion.
EVALUATION OF THE PROPORTIANALITY COEFFICIENT IN RUSANOV`S FORMULA FOR THE SURFACE TENSION ON THE BASIS OF COMPUTER SIMULATION OF NANOPARTICLES – 431 page.
N.Yu. Sdobnyakov, V.M. Samsonov, A.N. Bazulev, D.A. Novozhilova
Abstract: A method is proposed to calculate the proportionality coefficient K in Rusanov’s linear formula σ = KR for the surface tension of a small object using the size dependence of the specific total surface energy ε(R), where R is the particle radius. Contrary to σ(R), the ε(R) dependence be can easily enough found via computer simulation results.
Keywords: Rusanov’s formula for the surface tension of nanoparticles, conditions of thermodynamic stability for nanoparticles and nanoconstructional materials.
ON THE TECHNIQUE OF THE EVALUATION OF THICKNESS DEPENDENCES OF REFRACTIVE INDEX FOR NANOSIZED LIQUID FILMS BY ELLIPSOMETRIC METHOD – 444 page.
N.Yu. Sdobnyakov, N.V. Novozhilov, A.S. Antonov, E.A. Voronova, O.V. Mikhailova
Abstract: On the basis of the spectrum analysis of ellipsometric angles ψ and Δ, the technique of the evaluation of the thickness dependence of the refractive index for nanosized liquid films is outlined using the photometric spectroellipsometry.
Keywords: photometric spectroellipsometer, nanosized liquid films, refractive index, thickness dependence.
INFLUENCE OF CALCINATION TEMPERATURE ON STRUCTURAL CHANGES OF NANOSIZED ZIRCONIA – 450 page.
D.G. Selemeneva, A.A. Kravtsov, A.V. Blinov, M.A. Jasnaja
Abstract: The synthesis of nanosized zirconia by sol-gel method was performed. The optimal conditions for stable ZrO2 gel was determined, and then was set a point of gelation. Obtained samples of zirconia nanoparticles were studied by infrared spectroscopy and XRD analysis. Acid-base properties of the surface of the samples were studied by indicator method.
Keywords: sol-gel method, ZrO2 nanoparticles, infrared spectroscopy, X-ray difraction analysis, indicator method.
STUDY ON THE MICRO- AND NANOSTRUCTURE OF NdPrGdDyTbFeCoBAl PERMANENT MAGNETS – 456 page.
E.M. Semenova, M.B. Lyakhova, А.I. Ivanova, А.А. Lukin, Yu.V. Kuznetsova, D.Yu. Karpenkov
Abstract: Microstructure, phase composition and nanostructure of NdPrGdDyTbFeCoBAl permanent magnets were investigation by optical, electron and scanning probe microscopy. The parameters of the microstructure and of the magnetic domain structure and elemental composition of the phases of the permanent magnets type R2M14B ( R = Nd,Pr,Gd,Dy,Tb: M = Fe,Co,Al) were determined. The correlation between the hysteresis characteristics and micro- and nanostructure of the magnets was defined.
Keywords: permanent magnets, high coercivity state, microstructure, nanostructure, magnetic properties.
EFFECT OF SOLID COMPONENT OF DIFFUSION-HARDENING SOLDERS ON PROPERTIES OF CONNECTING LAYER – 463 page.
V.M. Skachkov, S.P. Yatsenko, L.A. Pasechnik, N.A. Sabirzyanov
Abstract: The article provides new formulations of gallium-based composite alloys. The influence of the composition of powder filler on the structure and properties of solder for the purpose of obtaining unique properties and expansion of areas of their use is investigated.
Keywords: diffusion-hardening composite alloys, solders, filler, structure, properties.
EFFECT OF THE CONTENT TUNGSTEN ON THE MECHANICAL PROPERTIES AND THERMAL STABILITY OF COMPOSITE MATERIAL BASED ON POLYSTYRENE – 471 page.
A.V. Smirnov, I.A. Gorbachev, I.V. Sinev
Abstract: The influence of the composition of the composite tungsten-polystyrene on its micro hardness and heat resistance was investigared. It is shown that the introduction of micropowder tungsten into the volume of polystyrene matrix results in the linear increase in the microhardness of the composite in the range of 0-3 vol. %. Further increasing the concentration of tungsten up to 30 vol. %, also results in the linear increase in the microhardness, but with a smaller slope. Thermal stability of samples monotonically depends on the concentration of tungsten and has a maximum at 10 vol. %.
Keywords: metal-polymer composite, micro hardness, thermal stability, thermogravimetry.
THE CHANGING OF GLASS PROPERTY SURFACE LAYERS, PROCESSED IN MELT SALT – 479 page.
Yu.K. Startsev
Abstract: Analysis of experimental data, pursuing the goal of either the glass strengthening for different purposes, or get on their surface property gradient layers for various purposes, allowed the author to offer closed physical-chemical model of the glass property changing and calculation algorithm, called coordination relaxation model. Fragmented information accumulated in the two applications of surface glass layer property changing, able to understand and explain under the proposed model, allowing to describe and to predict quantitatively values of the changes of the basic properties of glass.
Keywords: chemical hardening glass, gradient glass, glass property modeling.
PHENOMENOLOGICAL DESCRIPTION OF VITRIFICATION AND STRUCTURAL RELAXATION PROCESSES – 494 page.
Yu.K. Startsev
Abstract: Analysis of characteristics of relaxation processes of vitrification and their known phenomenological descriptions was done. A detailed examination of the microscopic description of vitrification and nature of atomic dynamics in glassy materials led the author to the conclusion that physical-chemical functions of fractional exponents, widely used for the spectrum of structural relaxation times.
Keywords: glassy state, relaxation processes, stretched exponent.
INVESTIGATION OF THE FORMATION PROCESSES OF URANIUM AND ALUMINUM OXIDES NANOCLUSTERS ON THE SURFACE OF OXIDIZED ALUMNUM USING DOUBLE LASER PULSES – 505 page.
D.S. Umreiko, А.I. Komyak, Е.V. Vileishikova, А.P. Zajogin
Abstract: This work presents the results obtained in studies of the production of variable valence uranium oxides at the surface of oxidized aluminum under irradiation by double laser pulses. The well developed aluminum surface activated by uranium oxides was produced with the use of a LSS-1 multichannel laser atomic-emission spectrometer with double pulses.
Keywords: spectral analysis, uranium complexes, laser atomic-emission spectrometry, double laser pulses.
THE EFFECT OF CALCIUM NITRATE ON THE PHOTOCHEMICAL FORMATION PROCESSES OF URANIUM NANOCLUSTERS IN THE SOLUTIONS OF URANYL PERCHLORATE IN ACETONE – 509 page.
D.S. Umreiko, А.I. Komyak, Е.V. Vileishikova, А.P. Zajogin
Abstract: Using the electron absorption method, the effects exerted by the physical and chemical properties of calcium nitrate solutions on the photopolymerization processes of acetone and on the photochemical nanocluster formation due to the tri-, tetra-, and pentavalent uranium complexes with organic ligands have been studied on LED-illumination of UO2(ClO4)2•5H2O solutions in acetone over the region 420-440 nm. The process patterns have been established.
Keywords: uranium, cations of metal, photochemical activity, electronic absorption spectra, acetone.
CHANGING THE SHAPE AND STRUCTURE OF COPPER NANOCLUSTERS SYNTHESIZED FROM THE GAS PHASE – 515 page.
I.V. Chepkasov
Abstract: To analyze thermal effects on the shape and structure of the synthesized copper nanoparticles, their smooth heating in the temperature range from 100 to 1200 К was produced. It was concluded that as a result of short-term heating, there was a significant ordering of the internal structure of 70 % of agglomerated nanoparticles with the preferential formation of spherical shape.
Keywords: computer simulation, copper nanoparticles, the structure, the gas phase.
SYNTHESIS AND STUDYING OF ACID-BASE PROPERTIES OF TiO2 – Ag NANOCOMPOSITE – 519 page.
M.S. Shama, A.A. Kravtsov, A.V. Blinov, M.A. Jasnaja, D.G. Selemeneva
Abstract: This article is devoted to studying the acid-base properties of the surface of titanium dioxide and Ag nanocomposite based on it (TiO2 modified nanosize silver) synthesized by sol-gel method.
Keywords: TiO2 nanoparticles, nanocomposite TiO2 – Ag, the sol-gel method, acid-base properties, the indicating method.
STRUCTURE, MICROHARDNESS AND THERMAL STABILITY OF RAPIDLY SOLIDIFIED Bi31Sn34Pb35 ALLOY – 527 page.
V.G. Shepelevich
Abstract: Results of investigations of structure, microhardness and stability of rapidly solidified Bi31Sn34Pb35 alloy are presented. Textured ε- phase and dispersive Sn and Bi particles are forming in rapidly solidified alloy. Ageing of foil course change of structure and increase of microhardness take place at the room temperature.
Keywords: rapid solidification, foil, alloy, phase, texture, microhardness, lead, tin, bismuth, ageing.
CONSTRUCTIVELY TECHNOLOGICAL PRINCIPLES OF CAPACITIVE HUMIDITY SENSING Al2O3 NANOSTRUCTURES AND SENSITIVE PARAMETERS STUDY – 533 page.
D.L. Shimanovich
Abstract: Volumetric-surface variants of capacitive MDM (metal-dielectric-metal) structures of the vertical direction based on high-ordered matrices of free anodic porous alumina membranes for applications in humidity sensing elements were designed. The improved humidity sensitivity, reduced response and recovery time over a wide humidity range were obtained due to preparing of alumina membranes with open-ended and widened pores without the barrier layer. Such technological approach allows to eliminate the effect of electrolyte anions embedded in pore walls on adsorption and desorption processes in humidity sensing elements.
Keywords: aluminum, electrochemical anodization, porous alumina, barrier layer, membrane, nanostructured material, humidity sensing element, adsorption, response time, recovery time, sensitivity.
MODELLING OF THE COPPER CLUSTER’S GROWTH: TOPOLOGICAL DESCRIPTION, STABILITY AND OCCURRENCE IN INTERMETALLICS – 541 page.
A.A Esser, V.S Myasnichenko, L.A. Myasnichenko, N.Yu. Sdobnyakov
Abstract: In this paper, we study the structure of the modeled copper clusters containing up to 100 atoms. The most stable configuration were determined by calculating the internal potential energy with using the Cleri-Rosato many-body potential. Using ToposPro we have performed the topological analysis of the Cu4 – Cu100 clusters, as a result one can see that the modeled clusters have the certain types of internal polyhedral cores. With increase of the size of the nanoclusters their occurrence in intermetallics monotonically decreases. The sequential topological growth of copper nanoclusters with internal icosahedron was realized only in certain size ranges.
Keywords: cluster, intermetallic compound, structure, topology.
THE SIZE DEPENDENCE OF SURFACE TENSION AND HOMOGENEOUS NUCLEATION OF CRYSTALS – 548 page.
V.M. Yurov
Abstract: In this paper we show that, despite various modifications and clarifications of the classical theory of nucleation, it is far from matching the experimental and theoretical data. The main reason for this is due to not taking into account the size dependence of the surface tension of the emerging centers of crystallization. For many metals the critical radius of the homogeneous crystal formation were calculated.
Keywords: crystallization center, surface tension, critical radius.
INFLUENCE OF MELT OVERHEATING NAPHTHALENE, DIPHENYL AND DIBENZYL ON CRYSTALLIZATION – 4 page.
V.D. Aleksandrov, O.A. Pokyntelytsia
Abstract: A sharp change in naphthalene, diphenyl, and dibenzyl crystallization behavior from the equilibrium without overcooling to the nonequilibrium-explosive with overheating was determined by thermoanalysis. The crystallization behavior depends on liquid phase overheating relative to the melting temperature. An average amount of the overheating that practically does not depend both on further overheating and number of heating – cooling cycles were calculated. A range of kinetic and thermodynamic parameters of crystallization was calculated using thermograms. By X-ray diffraction and optical microscopy changes in crystal structure were detected depending on the type of crystallization.
Keywords: naphthalene, diphenyl, dibenzyl, thermal analysis, melt overheat, subcooling, equilibrium and nonequilibrium crystallization, crystal structure, crystallization parameters.
ON THE TECHNIQUE OF PREPARING SAMPLES TO STUDY FRACTAL DIMENSION AND ELECTRICAL PROPERTIES OF SAMPLES USING A SCANNING TUNNELING MICROSCOPE – 15 page.
A.S. Antonov, O.V. Mikhailova, E.A. Vorovova, N.Yu. Sdobnyakov
Abstract: In this paper the technique of preparation of samples for the study of fractal dimension and obtaining the current-voltage characteristics using a scanning tunneling microscope has been demonstrated.
Keywords: sample preparation, scanning tunneling microscopy (STM), fractal dimension, current-voltage characteristics.
COMPUTER MODELLING METHODS FOR PREDICTING PERFORMANCE OF CATHODE MATERIALS FOR LITHIUM-ION BATTERIES – 22 page.
M.Yu. Arsent’ev, P.A. Tikhonov, M.V. Kalinina, T.L. Egorova, A.V. Shmigel
Abstract: Electrical conductivity, in particular ionic conductivity, is one of the major obstacles for further improvement of lithium-ion batteries and is expected to remain so in the foreseeable future. Without the high ionic conductivity of LiCoO2 it would not be possible to create Li – ion batteries based on it. Computer simulation is an important and critical component for the search of the best materials for Li-batteries. Increasing productivity while maintaining the accuracy of the calculations is the main condition for the selection of materials. In this study, we propose a new method based on the combined use of methods of crystal analysis and density functional theory. This method allows to plot topologies of the most energetically favorable migration paths and to analyze the value of the radius of channels without the use of resource-intensive computations.
Keywords: lithium ion batteries, supercapacitors.
THE POLYSCALE TRANSFORMATION FEATURES IN THE STEELS AND ALLOYS STRUCTURES AT THE HOT PRESS CONDITIONS – 29 page.
B.K. Barakhtin
Abstract: The results of the FSS steels and alloys hot pressing at T>0.5 Tmelt and range from 10 to 10 -3 s-1 are presented. At σ(ε) maps the auto oscillations stress were revealed. The dissipative mechanical energy estimates and structure investigations results have showed to auto oscillations by non equilibrium deform simultaneously at micro-, mezo- and macroscopic structures levels had caused. The structures transformations are self-organized as oscillation form on the chemical composition and the hot pressure regimes dependence.
Keywords: hot plastic deform, non equilibrium, mechanical energy dissipation, oscillation, structure self-organization.
FORMATION OF HYBRID CARBON SP2 AND SP3 PHASES FROM GRAPHENE LAYERS L4-8 -41 page.
E.A. Belenkov, M.I. Tingaev
Abstract: In this paper research of carbon compounds is connected, which can be obtained as a result of partial cross-linking of graphene layers L4-8 . It is established that after cross-linking and geometry optimization of graphene layers L4-8 only diamond-like phase or the original graphene layers L4-8 can be obtained.
Keywords: carbon, diamond, graphene, crystalline structure.
BAND STRUCTURE CALCULATIONS OF GRAPHENE POLYTYPES – 47 page.
E.A. Belenkov, A.E. Kochengin
Abstract: In this paper optimized structure of graphene layers L6, L3-12, L4-8, L4-6-12, and their band structure were calculated geometrically and by DFT.
Keywords: graphene, polytypism, band structure, modeling.
ELECTRONIC STRUCTURE OF LAYERED COMPOUNDS WHICH CONSISTS OF TWO- AND TRICOORDINATED CARBON ATOMS – 53 page.
T.E. Belenkova, V.M. Chernov
Abstract: In this paper the electronic structure of five major structural modification of graphyne: α-,β1-. β2-. γ1- and γ2- graphyne were calculated by method of density functional theory.
Keywords: polymorphism, carbon, graphene, graphyne, electronic structure, modeling.
FRACTAL STRUCTURE OF TITANIUM NITRITE DEPOSITED ON STAINLESS STEEL SUBSTRATE – 59 page.
Yu.V. Brylkin
Abstract: On the basis of images obtained using scanning tunneling microscope, it was shown that the fractal dimension can be considered as some universal surface characteristic of the titanium nitrite, deposited on stainless steel.
Keywords: fractal, scanning tunneling microscopy, surface topology.
MODEL OF CRYSTALLIZATION AS THERMODYNAMICAL PARAMETERS FLUCTUATION – 66 page.
A.A. Burtsev
Abstract: In this thesis self-organization processes under crystallization of sodium hydroxide while drying droplets of different volumes on a glass substrate has been investigated. Similar complex crystal structures arise in the action of laser radiation on the surface of metals. Theoretical model includes the mathematical description of non-stationary fluctuations of thermodynamical parameters.
Keywords: change of phase, crystallization, dendritic arborescent crystals, fluctuations.
N-DIAMOND: BOND MECHANICS – 74 page.
S.A. Voropaev, A.Yu. Dnestrovsky, E.A. Podolskaya, N.V. Dushenko
Abstract: Results of the synthesis of -diamond in experiments with cavitation in carbon containing liquids are presented. A mechanical model of the chemical bonds between carbon atoms in the diamond with the availability of a stable FCC crystal lattice structure is developed.
Keywords: diamond, n-diamond, FCC-carbon, cavitation, the interaction potential.
OBTAINING METAL COVERINGS AND THEIR PROPERTIES STUDYING – 82 page.
Е.S. Gerasimova, Е.V. Vladimirova, В.G. Vasilyev, Т.S. Karpova, A.Sh. Haliullina
Abstract: Properties of metals films ( Cu, Fe, Ni, Co ) obtained by thermohydrolysis in the recovery atmosphere on different bases are studied.
Keywords: Cu, Fe, Ni, Co covering, thermohydrolysis, morphology, phase composition, X-ray diffraction method, electron microscopy.
«STRUCTURE OF ALKYNES C2H2– C9H16 HEAT OF VAPORIZATION» CORRELATION – 87 page.
V.V. Grebeshkov, V.M. Smolyakov
Abstract: To investigate the quantitative correlation «structure of 132 alkynes C2H2– C9H16-property», topological indexes χ Randich and Δi3 were used. Then using the two-parameter functions, quantitative correlation «structure of alkynes – property» are investigated According to the obtained formulas, numerical calculations of the heats of vaporization were found for alkynes LHTK C2H2– C9H16 at normal boiling point not studied experimentally.
Keywords: topological index, alkynes, heat of vaporization, correlations «TI-alkyne property».
MODELING OF CLUSTERS Bi8-nSbn – 95 page.
E.N. Gribanov, O.I. Markov, Yu.V. Khripunov
Abstract: In this paper results of calculations by quantum-chemical methods of structure and power parameters of nanoclusters of bismuth-antimony Bi8, Bi7Sb1, Bi6Sb2, Bi5Sb3, Bi4Sb4, Bi3Sb5, Bi2Sb6, Bi1Sb7, Sb8 are presented.
Keywords: cluster, bismuth, antimony semiconductor – semimetal transition.
SIZE EFFECT OF TEMPERATURE ON CONTACT MELTING OF SMALL-DIMENSIONAL PHASES – 101 page.
O.V. Gudieva, D.A. Kambolov, P.K. Korotkov, V.A. Sozaev
Annotation: The attempt to derive the relation for the temperature of contact melting of small-dimensional phases (nanoparticles, nanofilms) has been made with account for the A.I. Rusanov size dependence of the surface tension of nanoparticles.
Keywords: size effect, surface energy, temperature of contact melting, nanofilms, nanoparticles, nanowires.
QUANTUM CHEMICAL DESIGNING OF ENDOHEDRAL CONTAINING INDIUM DERIVATIVES OF BUCKMINSTER FULLERENE C60 AND C70 FOR DEVELOPMENT RADIONUCLIDE NANOSIZED AGENTS THAT DESTROY A TUMOR – 105 page.
Е.А. Dikusar, V.М. Zelenkovskii, А.L. Pushkarchuk, V.I. Potkin, D.А. Rudakov, S.J. Kilin, А.G. Soldatov, S.А. Kuten, A.N. Khmialeuski, L.F. Babicheu
Abstract: In this work a simulation was performed of the electronic structure and geometry of endohedral containing indium derivatives of Buckminster fullerene C60 and C70 and monoester – a heterocyclic carboxylic acid derivative.
Keywords: electronic structure simulation, endohedral containing Indium derivatives of Buckminster fullerene, agents that destroy a tumor.
PHOTOINDUCED CHANGES OF OPTICAL CONSTANTS IN CHALCOGENIDE GLASS SEMICONDUCTORS – 116 page.
V.I. Ivanov, S.R. Simakov
Abstract: The results of an experimental research of the photoinduced optical constants change in As2Se3 films are described at different temperatures of exhibiting. It is shown, that the basic experimental dependences describing photoinduced changes of optical constants are coordinated with model of the microheterogeneous environment with a local warming up of microareas.
Keywords: chalcogenide semiconductors, photoinduced changes, optical constants.
DYNAMIC HOLOGRAMS EFFICIENCY IN A NANOSUSPENSION – 122 page.
G.D. Ivanova, S.I. Kirjushina, A.V. Mjagotin
Abstract: A theoretical analysis of the dynamic holograms efficiency in the dispersion liquid medium with electrostrictive nonlinearity is carried out. The amplitudes of the first harmonics depends on the intensity of the light at a nonlinear regime.
Keywords: electrostriction, dispersion liquid, dynamic holography.
PROPERTIES OF AMORPHOUS NANO-SILICA OBTAINED BY PULSED ELECTRON EVAPORATION – 126 page.
V.G. Ilves, S.Yu. Sokovnin, A.M. Murzakaev
Abstract: In this work the amorphous nanopowder SiO2 with a specific surface 154 m2/g was produced by the method of pulsed electron beam evaporation of target from pyrogenic amorphous NP Aerosil 90 (90 m2/g). Nanoparticles of NP SiO2 showed the improved magnetic and thermal properties in comparison with NP Aerosil 90. Possible reasons of emergence dº ferromagnetism at the room temperature in amorphous NP SiO2 are discussed.
Keywords: pulsed electron beam, nanopowder SiO2 , Aerosil 90, dº ferromagnetism SiO2.
CALCULATION OF SURFACE TENSION ISOTHERMS, ADSORPTION AND SURFACE CONCENTRATIONS OF ALLOY COMPONENTS OF BINARY LITHIUM SODIUM SYSTEM IN SOLID STATE – 133 page.
Z.Kh. Kalazhokov, Zaur Kh. Kalazhokov, R.I. Khatsukova, E.Kh. Sherieva, Kh.Kh. Kalazhokov
Abstract: It is suggested a method to estimate values of surface thermodynamic parameters: surface tension, adsorption and surface concentrations of components in solid state by the electron work function. In the example of Li-Na system was shown that sodium is surface active with regard to lithium in solid state, and the values of some parameters in solid state exceed several times the appropriate parameters in liquid state.
Keywords: surface tension, adsorption, work function, surface concentration.
INVESTIGATION OF ELECTROPHYSICAL PROPERTIES OF LEAD SILICATE
GLASSES C87-2 – 138 page.
A.M. Karmokov, O.A. Molokanov, O.O. Molokanova, Z.V. Shomakhov
Abstract: We experimentally investigated the temperature dependence of the electrical conductivity and the kinetics of lead-silicate glass C87-2. The influence of mass transfer under the influence of an electric field on the electrical conductivity was also. evaluated via the dependence of the size of nanocrystals on the time of isothermal annealing.
Keywords: isothermal annealing, kinetics of the conductivity of lead-silicate glass, structural transformations, specific conductivity, phase formation, the activation energy of conduction.
IMPURITY REDISTRIBUTION IN THE ALUMINUM MELT RESULTING ACOUSTIC IMPACT – 144 page.
R.Yu. Karmokova, A.M. Karmokov
Abstract: In this paper a study of redistribution of impurities after aluminum acoustic impact frequency of 5 and 15kHz on its melt is performed.
Keywords: aluminum, acoustic impact, cavitation bubbles segregation.
POLYTHERMS OF ANGLES OF WETTING OF POROUS NICKEL BY TIN-BARIUM AND INDIUM-SODIUM MELTS – 149 page.
A.Z. Kashezhev, R.A. Kutuev, A.R. Manukyants, M.Kh.Ponegev, V.A. Sozaev, A.Kh. Shermetov
Abstract: The polytherms of angles of wetting of the porous carbonyl nickel (with 30% porosity) by tin-barium and indium-sodium melts have been studied for the first time. The temperature thresholds of the beginning of wetting have been discovered: T>475ºC in case of tin-barium melts and T>250ºC in case of indium-sodium ones. The bunch-shaped arrangements of intermetallics In8Na5 with sizes 7-9 microns have been revealed on the surface of the porous nickel wetted by the melt In-0,5 wt.% using the raster electron microscopy.
Keywords: angles of wetting, polytherms, tin-barium and indium-sodium melts, porous nickel, morphology of surface.
NANO-STAGE MECHANISM OF CRYSTAL NUCLEATION KINETICS FROM LIQUID PHASE – 155 page.
B.I. Kidyarov
Abstract: The set of experimental data, vouched for crystal nucleation by stages from liquid phase, has been collected. The initial stage includes a formation some metastable phase, and last stage – a formation of stable phase. The influence of such crystal nucleation mechanism on process kinetics and formation of defect or perfect crystals has been noted.
Keywords: nucleation, nano-stage mechanism, metastable and stable phases, melting-crystallization temperatures, dimensional dependence.
STRUCTURAL-PHASE STATE OF THE SURFACE LAYER OF AI-SI ALLOY AFTER ELECTRON-ION-PLASMA TREATMENT – 162 page.
A.A. Klopotov, Yu.F. Ivanov, E.A. Petrikova, A.D. Teresov, V.E. Gromov, E.A. Budovskih
Abstract: The results of silumin surface modification by combined method including irradiation by plasma produced in the electric explosion of conductive material followed by a pulsed electron beam treatment are presented. The formation of a multilayer polyphase sub-micro and nanoscale structure with high mechanical and tribological properties is revealed. The results obtained are discussed from the viewpoint of thermodynamics.
Keywords: silumin, electroexplosive alloying, high-intensity pulsed electron beam, structure, properties, phase diagram.
SURFACE PHOTOEMISSION OF THE K/W(100) SYSTEM UNDER – 171 page.
M.V. Knat’ko, M.M. Lapushkin
Abstract: The coadsorption of potassium and oxygen on W(100) by the threshold photoemission spectroscopy was studied. It is shown that coadsorption of potassium and oxygen on the W(100) leads to the formation a dielectric layer with a possible stoichiometry K2O2.
Keywords: threshold photoemission spectroscopy, adsorption, surface states, metal oxides.
STUDY OF DISPERSION PHENOMENA OF A NANOSTRUCTURED SHUNGITE ROCK – 178 page.
S.V. Kovalevskii, I.E. Kalashnikov
Abstract: Dispersion phenomena of a nanostructured shungite rock have been studied in different fluids. Dispersion was shown to be useful for classification of nanostructured shungite rocks by specified constituents and can be suggested as pretreatment techniques for obtaining of filling and modifying agents and using those in metal-matrix composite materials.
Keywords: shungite rock, nano-structurization, metall-matrix composites, dispersion, X-ray diffraction analysis, Raman spectroscopy, electron microscopy.
LASER SYNTHESIS AND OPTICAL DIAGNOSTICS OF SILVER PLASMONIC NANOSTRUCTURES ON THE GLASS SURFACE – 186 page.
K.V. Kozadaev, V.K. Goncharov, A.P. Mikitchuk, M.A. Prohorovich
Abstract: The present paper is dedicated to description of formation method for surface silver nanostructures during the laser erosion of metal target under atmospheric pressure. The obtained monolayer of silver nanoparticles is investigated by implementation of the methods of SEM, AFM and spectral analysis of PPR band.
Keywords: laser synthesis, monolayer of silver nanoparticles, surface plasmon resonance.
DETERMINE THE OPTIMUM PARAMETERS OF THE SYSTEM FOR CREATING GOLD NANOSCALE CONTACTS BETWEEN TRACKS OF NANOSCALE BUSES – 193 page.
A.Yu. Kolosov, D.N. Sokolov, N.Yu. Sdobnyakov, M.A. Kharitonova
Annotation: The simulation of the creating gold nanoscale contacts between tracks of nanoscale buses for different system configurations by Monte-Carlo method was carried out. The interaction between nanoparticles was described by many-body Gupta potential. The optimum parameters for creating nanoscale contacts between tracks of nanoscale buses have been determined. The final stable structure of nanoscale contacts has been analyzed.
Keywords: nanoscale contact, gold nanoparticles, coalescence, Monte-Carlo method, Gupta potential, phase transition, stability.
THERMAL DECOMPOSITION OF POLYMER COMPOSITE OF POLYTETRAFLUOROETHYLENE AND DETONATION NANODIAMONDS – 202 page.
A.P. Koscheev, P.V. Gorokhov, A.A. Perov, C.A. Khatipov
Abstract: The effect of nanodiamond filler on the thermal decomposition of polytetrafluoroethylene composites under vacuum pyrolysis was studied by means of thermodesoption mass spectrometry. The results indicate that the presence of nanodiamonds affects both the temperature profiles and the chemical composition of decomposition products.
Keywords: polytetrafluoroethylene composites, detonation nanodiamond, thermal destruction, thermodesorption mass spectrometry.
EFFECT OF SURFACE CHEMISTRY OF NANODIAMOND FILLER ON THE PROPERTIES OF POLYTETRAFLUOROETHYLENE COMPOSITES – 208 page.
A.P. Koscheev, A.A. Perov, P.V. Gorokhov, A.V. Tereshenkov, N.A. Chukov, S.A. Khatipov
Abstract: The tribology properties of polymer composites of polytetrafluoroethylene filled with detonation nanodiamonds of various types were studied. The composite properties were found to depend on the oxygen-containing groups on nanodiamond surface. The direct evidence of chemical interaction of nanodiamond with polymer matrix during preparation (sintering stage) of composite was obtained.
Keywords: polytetrafluoroethylene composites, nanodiamond, surface chemistry, thermodesorption mass spectrometry.
ELECTROCHEMICAL DEPOSITION OF CALCIUM PHOSPHATE COATINGS ONTO TITANIUM AND CARBON SUBSTRATES – 214 page.
V.K. Krut’ko, A.I. Kulak, O.N. Musskaya, L.A. Lesnikovich, S.A. Ulasevich
Abstract: The calcium phosphate coatings on titanium and carbon (fabric, felt) substrates have been obtained using electrochemical deposition in water electrolyte at рН 3,2-3,6 and room temperature. In accordance with XRD data it was determined that the calcium phosphate coatings consist of brushite CaHPO4•2H2O, α-tricalcium phosphate Ca3(PO4)2 and additional amount of octacalcium phosphate phase Ca8H2(PO4)6•5H2O on carbon substrates.
Keywords: calcium phosphates, biocompatible coatings, electrodeposition.
ELECTRON-STIMULATED OXIDATION OF THE SURFACE POLYCRYSTALLINE THALLIUM – 220 page.
D.A. Krimshokalova, I.B. Ashkhotova, O.G. Ashkhotov
Abstract: In this paper, using Auger electron spectroscopy and electron energy-loss spectroscopy the kinetics of oxygen adsorption on thallium was studied in two cases: under continuous electron irradiation (100-1000 eV) and without depending on the exposure time in oxygen 10-6 at a partial pressure oxygen Torr at room temperature.
Keywords: exposure, electrons, energy, spectroscopy, surface oxidation kinetics, radiation, adsorption, concentration, monolayer, thallium.
A STATIONARY THERMAL LENS RESPONSE OF A NANOLIQUID – 227 page.
A.I. Livashvily, G.D. Ivanova, V.K. Khe
Abstract: The stationary two-dimensional thermodiffusion in a two component medium in the Gaussian beam radiation field was analyzed. The expression for a thermo-lens medium response is obtained.
Keywords: thermal lens, thermodiffusion, two components medium.
STRUCTURE REFINEMENT PECULARITIES AND SOLID SOLUTION FORMATION IN THE CAST Cu-Fe ALLOU, SUBJECTED TO SEVERE PLASTIC DEFORMATION – 231 page.
A.V. Lukyanov, A.A. Churakova, A.V. Ganeev, V.D. Sitdikov, D.V. Gunderov
Abstract: The effect of high pressure torsion (HPT) on the microstructure of Cu-Fe 36% wt alloy has been studied. The initial Cu-Fe alloy has a dendritic structure, the length of dendrites is up to 100 µm. As a result of HPT (20 anvil rotations at 400ºC) the nanostructured state is formed. The average grain size of the -Cu and α-Fe is 60 and 35 nm correspondingly. The refinement of α-Fe dendrites occurs, and a microstructure with inclusions with a size from 0,1 to 5 µm distributed in the copper matrix forms. A volume fraction of the Fe phase reduces from initial 37% up to 15% after HPT. The concentration of copper in the lattice dissolved iron reaches 20%. Subsequent annealing at 700ºC for 1 hour results in some coarsening of α-Fe particles, as compared to the state after HPT. However, the dendritic structure typical of the cast alloy does not recover; it remains dispersed with a size of α-Fe particles less than 20 µm. As a result of HPT the alloy microhardness increased from 1800 to 4000 MPa. The subsequent annealing at T=700ºC decreased the microhardness to 2700 MPa, but this value is 1,5 times higher than that in the initial as‑cast state.
Keywords: nanocomposite, high pressure torsion deformation, Cu-Fe alloy.
ON THE DEPENDENCIES OF THE COEFFICIENT OF THERMAL EXPANSION VERSUS SIZE AND SHAPE OF NANOCRYSTAL – 239 page.
M.N. Magomedov
Abstract: A model of nanocrystal in the form of a rectangular parallelepiped with a variable surface shape (RP-model) is used to study of the dependencies of the coefficient of thermal expansion (αp) versus size and surface shape of the nanocrystal of the simple matter. The calculations for the nanocrystal of silicon have shown that αp increases at reduction N, moreover at reduction of the temperature the dependency αp(N) is increasing. At the isomorphous reduction N along isotherm of the function αp(N) at defined size (for cube N≈1125) passes from the negative into the positive field.
Keywords: nanocrystal, size, shape of the surfaces, thermal expansion.
FRACTAL ANALYSIS OF PHOTOINDICED LIGHT SCATTERING PICTURES IN LiNbO3 CRYSTALS – 247 page.
D.V. Manukovskaya, N.V. Sidorov, M.N. Palatnikov, O.R. Starodub
Abstract: The dynamics of laser-induced defects in different layers of photoinduced light scattering (PILS) pictures in lithium niobate was researched by analysis of fractal dimension of PILS picture layers. Stoichiometric LiNbO3 crystal had different genesis. This method was compared with the method of measurement of PILS indicatrix opening angle. The transition of energy between PILS layers was detected.
Keywords: lithium niobate, photoinduced light scattering, laser-induced defects, fractal dimension.
FORMING DISSIPATIVE STRUCTURES IN POROUS ONODIC OXIDE OF ALUMINA – 253 page.
E.S. Markaryan
Abstract: In this paper we consider the processes of the formation of dissipative structures in porous anodic oxide on alumina. Using the theory of bifurcations due regularity of the formation oxide. Were obtained depending on the characteristic of the growth kinetics of anodic oxide. Spatio-temporal ordering is regarded as a self-oscillating and auto-wave processes.
Keywords: anodic aluminum oxide, growth kinetics, dissipative structures, bifurcation point.
PHASE TRANSITIONS IN THE FRUSTRATED ISING MODEL ON A SQUARE LATTICE WITH NEAREST NEIGHBOR INTERACTIONS – 261 page.
A.K. Murtazaev, M.K. Ramazanov, M.K. Badiev
Abstract: The phase transitions in the two-dimensional Ising model on a square lattice are studied using a replica algorithm, the Monte Carlo method, and histogram analysis with allowance for the next-nearest-neighbor interactions in the range 0.1≤r≤1.0. A phase diagram is constructed for the dependence of the critical temperature on the next-nearest-neighbor interaction.
Keywords: Monte Carlo, Izing model, phase transition, antiferromagnetic frustration.
MATHEMATICAL MODEL OF DIRECTED GROWTH OF THE REGULAR FCC CLUSTER WITH A CENTRAL ATOM – 267 page.
V.S. Myasnichenko, N.Yu. Sdobnyakov
Abstract: In this paper clusters of the FCC structure with short-range interaction forces between atoms have been considered. The interaction only between nearest neighbors has been taken into account. Algebraic relations for the number of atoms and the number of bonds between neighbors in the cluster have been obtained, it has been allowed to evaluate the surface energy of the cluster in an analytical form.
Keywords: FCC lattice, cluster, coordination number, surface.
CALCULATION OF STRESS-STRAIN STATE OF STRETCHING NANOTUBES WITH DEFECTS – 273 page.
Y.Е. Nagorny, A.V. Akavity, V.I. Repchenkov
Abstract: This paper presents the results of numerical calculation and analysis of the stress-strain state of a regular straight single-walled open carbon nanotube with vacancies in tension.
Keywords: carbon nanotubes, defects, vacancies, stress-strain state.
MAGNETIC PROPERTIES OF GARNET Y3Fe5O12 NANOCRYSTALS PREPARED BY COPRECIPITATION METHOD – 280 page.
Nguyen Anh Tien
Abstract: Yttrium iron garnet Y3Fe5O12 nanocrystalline powders were synthesized by simultaneously dehydrating of hydroxide of iron (III) and yttrium, and then heating in the air environment. Garnet Y3Fe5O12 nanocrystals at the size of 30 nm formed after calcinating up to 775ºC had large saturation and high coercive force (H c =60 Oe).
Keywords: coprecipitation method, magnetic properties, nanocrystal, garnet ferrite,Y3Fe5O12 .
QUANTITATIVE CORRELATION «STRUCTURE DIALKENES C4H6-C10H18 – THE HEAT OF VAPORIZATION» – 287 page.
D.Yu. Nilov, V.M. Smolyakov
Abstract: To investigate the quantitative correlation «structure of 1012 dialkenes C4H6-C10H18 – property» topological indices χGi=Gj and were used. Using the two-parameter functions quantitative correlation «dialkenes structure – property» are investigated. According to the obtained formulas, numerical calculations of the heats of vaporization at normal boiling point LHTK dialkens C4H6-C10H18 not studied experimentally. Dependences «dialkenes structure – property» are considered
Keywords: topological index, dialkyl, heat of vaporization, correlations «TI-dialkyl property».
ATOMIC STRUCTURE OF CLUSTERS ZIRCONIUM ZrN MOLECULAR DYNAMICS SIMULATION – 295 page.
N.A. Pankin
Abstract: Various isomers of free clusters of zirconium ZrN (N=4÷15 ) were studied. The results were obtained using molecular dynamics simulation and many-body Clery and Rosato interaction potential. The average length and the binding energy, the coordination number and the frequency of occurrence of various isomers were calculated.
Keywords: clusters of zirconium, classical molecular dynamics, many-body potential, atomic structure.
NEW POTENTIAL OF INTERPARTICLE INTERACTION ON THE BASIS OF SHORT MODEL OF SPHERICAL SHELLS – 301 page.
G.G. Petrik
Abstract: Study of analytical and computational capabilities for the molecular model of spherical shells has been continued. New results have been obtained. It is found that two terms mainly contribute to the potential of spherical shells (eight contributions). Calculations show that for all values of model objects rigidity it is fully justified the complete replacement of adequate potential of spherical shells by the truncated potential corresponding to the interaction of near arc-“dipoles”. This makes it possible to apply more simple function for computer calculations.
Keywords: modeling, molecular model, potential of spherical shells, model potentials, parameters, singular points, truncated potential.
INTERFACE FORMING WITH MUTUAL SUPERPOSITION OF D-METAL CLUSTER SURFACES AND MONOLAYERS OF GRAPHENE, SILICENE AND GERMANENE – 311 page.
V.A. Polukhin, N.S. Mitrofanova, E.D. Kurbanova
Abstract: Analyzing MD simulation data on the thermic evolution of transition metal nanoclusters (transition metals: Pd, Ni ,Cu ) deposited on graphene substrates specificities have been revealed of such main factors of melting processes and premelting stage including as the nucleation and the kinetic activation of upper cluster shell fluidization and coordination transformation especially in contact interlayer zones of grain transition metals nanocluster/graphene interfaces with different cohesive energies. The following sharp thermostability decreasing of clusters as the consisting and functional interactive units of the whole effective electronic and catalytic systems has been also displayed.
Keywords: nanoclusters, MD simulation, interlayer surface zone (interface) of metal/graphene, graphene substrate.
STRUCTURAL AND TECHNOLOGICAL DEVELOPMENT OF SURFACE LAYERS OF SHAPE MEMORY MATERIALS. HIGH SPEED FLAME SPRAYING – 322 page.
P.O. Rusinov, Zh.M. Blednova
Abstract. A universal system for the preparation of nanostructured coatings with shape memory effect, a coating and the necessary post-processing are considered. Control parameters of the surface modification of steel material with shape memory effect, controlling the structural state of the material, are found.
Keywords: shape memory effect, high-speed flame spraying, nanostructure, nikelidtitanium
CORRESPONDING STATES LAW FOR SIZE DEPENDENCE OF MELTING TEMPERATURE – 330 page.
V.M. Samsonov
Annotation: Size dependence of the nanocluster melting temperature Tm has been analyzed using some similarity considerations and generalized Thomson’s formula Tm= Tm(∞)(1-α/R) where R is the particle radius, Tm(∞) is the macroscopic melting temperature and α is a parameter having the dimension of length and being the reduction parameter for R . Using Thomson’s formula and extrapolation to Tm=0K, the parameter α was calculated for nanoclusters of several metals with different types of lattice. It has been found that in most cases this parameter is close in magnitude to the first coordination sphere radius.
Keywords: melting temperature, size dependence, metal nanoclusters, thermodynamic similarity theory.
SONOCHEMICAL IMMOBILIZATION OF NANOCLUSTERS OF MOLYBDENUM OXIDE ON THE NICKEL SURFACE – 335 page.
T.V. Sviridova, A.S. Logvinovich, A.V. Kondratjuk, D.V. Sviridov
Abstract: The paper deals with the sonochemical modification of the surface of galvanic nickel plating with nanoclusters resulting from the polycondensation of oxo-acid (with the use of the molybdic acid as the example). The results of the investigation of thus obtained metal-oxide film nanocomposite are presented.
Keywords: metal-oxide clusters, oligomers, molybdic acid, sonochemical synthesis, electrochemical nickel coatings.
САLCULATION OF THE HEAT OF FUSION AND THE HEAT OF FREEZING SIZE DEPENDENCIES FOR METAL NANOPARTICLES – 342 page.
N.Yu. Sdobnyakov, D.N. Sokolov, V.S. Myasnichenko, A.N. Bazulev
Abstract: On the basis of temperature dependencies of internal energy the size dependences of heat of fusion and heat of freezing for gold, cuprum, aluminum and cobalt nanoclusters have been calculated. For the simulation the Monte-Carlo method has been used and interaction between atoms has been described by many-body Gupta potential.
Keywords: heat of fusion, heat of freezing, Monte-Carlo method, Gupta potential, metal nanoclusters.
INVESTIGATION OF THICKNESS DEPENDENCES OF REFRACTIVE INDEX FOR NANOSIZED ACETONE FILM BY ELLIPSOMETRIC METHOD – 349 page.
N.Yu. Sdobnyakov, N.V. Novozhilov, A.S. Antonov, E.A. Voronova, O.V. Mikhailova
Abstract: On the basis of analyzing the spectrum of the ellipsometric angles Ψ and Δ the investigation of thickness dependence of refractive index for nanosized acetone films on silicon surface using the photometric spectroellipsometer was carried out.
Keywords: photometric spectroellipsometer, nanosized acetone films, refractive index, thickness dependence.
INVESTIGATION OF THE STRUCTURAL CHARACTERISTICS OF THE COPPER NANOCLUSTERS IN MELTING/CRYSSTALLIZATION PROCESS – 353 page.
N.Yu. Sdobnyakov, M.A. Khazitonova, A.P. Andriychuk, A.N. Bazulev, I.V. Kartashov, P.V. Komarov, D.N. Sokolov
Annotation: In this work the investigation of the structural characteristics of the copper nanoclusters in the melting/crystallization process has been carried out. The possibility of the determination of the phase transition temperature has been shown by the temperature dependence of the mean value of the first coordination number. The process of the forming FCC/HCP structures for copper nanoclusters during melting and crystallization has been described.
Keywords: copper nanoclusters, melting and crystallization, Monte-Carlo method, Gupta potential, first coordination number, local density, FCC structure, HCP structure.
EFFECT OF THE STRUCTURE AND SYMMETRY ON THE THERMODYNAMIC PROPERTIES OF NANOPARTICLES WITH THE «MAGIC» NUMBER OF ATOMS – 362 page.
N.Yu. Sdobnyakov, V.S. Myasnichenko, A.P. Andriychuk, D.N. Sokolov
Abstract: The investigation of the thermodynamic characteristics of the gold nanoclusters with «magic» numbers of atoms in melting/crystallization phase transition has been carried out. Using the temperature dependence of the specific internal energy of nanoclusters, the melting temperature has been determined.
Keywords: nanoclusters, phase transition, melting temperature, «magic» numbers.
[C60]- FULLERENE.COUNTING AND ORDERING ISOMER OF SUBSTITUTIONS ON THE TOPS, EDGES, AND FACES – 370 page.
V.M. Smolyakov, D.V. Sokolov, D.Yu. Nilov, V.V. Grebeshkov
Abstract: This paper discusses the substitution isomers on vertices, edges and faces of the [C60] fullerene. The derivation of the isomers based on Polya theorem. Installed formula symmetry Z , generating functions for determining the number of chiral and non-chiral isomers substitution distribution isomers families ρ(m), and depending on the number m of seats substitution. By additive scheme calculated thermodynamic properties (Δf Hº298, Sº298, Cº298, ΔHsubl, Δf Gº298,lgK298) gaseous [C60] – [C100] -fullerens.
Keywords: fullerenes, counting and ordering of isomers replacement elements and symmetry operations, generating functions, chirality, achiral.
BULK AND SURFACE NANOSTRUCTURING OF TITANIUM BASED ALLOYS – 379 page.
V.V. Stolyarov
Abstract: The paper is a brief review of structure refinement deformation methods for bulk samples of titanium alloys with different nature. Typical microstructures of alloys in nanostructured and ultrafine-grained state are demonstrated.
Keywords: microstructure, deformation, rolling, pressing, forging.
PRELIMINARY MATHEMATICAL MODEL OF A STRATIFICATION OF METAL MELTS IN CAPILLARIES – 390 page.
N.P. Ouglev, S.N. Ouglev
Abstract: The preliminary mathematical model of the stratification process based on assumed special properties of mononuclear skin (interphase layer) of a melt describing satisfactory all experimental results on stratification of metal melts in capillaries is proposed. The model uses Landay’s equation for the barometric stratification, and the first order kinetic equation as well.
Keywords: stratification of metal melts, cluster, barometric equation, interface fluidity.
EXPERIMENTAL TESTING OF CLUSTERS STABILITY IN METAL MELTS – 397 page.
N.P. Ouglev
Abstract: Effect of conservation the cluster structure of metal melts dew to cooling from 730ºC to 230ºC is researched. The dimension of clusters does not advance to equilibrium size during two hours attached to 230ºC . This fact shows the kinetic difficulties to change the mass of clusters and ring liquid metal. The results also show indirectly the existence of clear-cut boundary between clusters and surround melt.
Keywords: metal melts, cluster, barometric distribution, the bundle in the capillary, the inheritance of the structure.
SPECTRAL STUDIES OF THE PHOTOCHEMICAL FORMATION OF THE VARIABLE VALENCE URANIUM COMPLEXES IN ACETONE WITH DMSO – 402 page.
D.S. Umreiko, Е.V. Vileishikova, А.P. Zajogin, А.I. Komyak, S.D. Umreiko
Abstract: Using the electronic and IR absorption methods, the photochemical formation processes of the nanoclusters of three-, tetra-, and pentavalent uranium with organic ligands on LED illumination (430-450 nm) of the solutions of UO2(ClO4)•5H2O with DMSO in acetone have been studied. The possibility for deposition of the tetra- and pentavalent-uranium complexes onto the glass substrate has been established.
Keywords: spectral analysis, uranium complexes, uranyl nitrate, uranyl perchlorate, band intensities, organic ligands.
SPECTRAL STUDIES OF THE AlO AND AlN RADICALS FORMATION PROCESSES IN THE PLASMA WHEN OXIDIZED ALUMINUM IS SUBJECTED TO SERIES OF DOUBLE LASER PULSES – 409 page.
А.R. Fadaijan, Bazzal Khodor, Е.S. Voropay, А.P. Zajogin
Abstract: The effect of an additional laser pulse on the desired formation of the component and charge composition of the surface laser plasma has been studied by the laser spark spectrometry method with the use of a LSS-1 spectrometer. The possibility to increase a portion of AlO and AlN and radicals in the plasma when the target is subjected to a series of double laser pulses has been demonstrated. The influence exerted by laser parameters on the formation of the desired ionic and molecular composition of the plasma has been shown.
Keywords: spectral analysis, AlO and AlN radicals, double laser pulses, laser ablation, processes in the plasma.
TO THE QUESTION OF REACTIONARY INTERACTION IN B-C-N SYSTEM WITH A PRESSURE OF 12 GPa – 415 page.
V.P. Filonenko, I.P. Zibrov, N.N. Kuzin, M.V. Trenikhin
Abstract: The paper presents experimental results of reacting between carbon nitride and amorphous boron under high pressure and temperature. It is shown that below the degradation temperature of carbon nitride get ordered graphite-like C3 N4 phase fails. In a mixture with boron significantly impeded the formation of hetero-graphene phase. At a temperature of about is 1500ºC formed finely diamond-like phase crystal size ranging from tens to hundreds of nanometers. Hetero-diamond cBCxN phase has a basic structure of cubic boron nitride in which carbon atoms are replaced atoms of boron and nitrogen.
Keywords: high pressure, carbon nitride, boron, reacting, hetero-diamond phase.
INFLUENCE OF SODIUM CHLORIDE BARRIER ON THE SIZE AND PARTICLE MORPHOLOGY OF SYNTHESIZED COBALT OXIDE – 424 page.
A.Sh. Khaliullina, V.G. Vassil’ev, E.V. Vladimirova, V.I. Pastukhove, T.S. Karpova, E.S. Gerasimova
Abstract: Powders of cobalt oxide consisting from different size and morphology particles have been obtained by methods of thermal hydrolysis, thermal hydrolysis with sodium chloride as a barrier and thermal decomposition of cobalt oxalate. The size and morphology of the particles in obtained powders were investigated to the dependence of synthesis method.
Keywords: thermohydrolisis, barrier, sodium chloride, cobalt oxalate, cobalt oxide, nanoparticles, morphology.
STRUCTURE AND THERMAL STABILITY OF RAPIDLY SOLIDIFIED SN-IN-SB – 430 page.
V.G. Shepelevich
Annotation: Results of investigation of phase composition, grain structure and of its change under the next annealling for Sn-In-Sb alloys are presented.
Keywords: rapidly solidification, foil, phase, grain, texture, coalescence, recrystallization.
TECHNOLOGICAL METHODS FOR SYNTHESIS OF HIGH-ORDERED MEMBRANE NANOSTRUCTURED MATRICES BASED ON POROUS ANODIC ALUMINA – 438 page.
D.L. Shimanovich
Abstract: Technological methods for the formation of 30–70 μm thick free porous one-layer Al2O3 membranes with open-ended modificated pores from 50 to 90 nm in diameters by a two-stage one-sided anodization in oxalic acid electrolyte and combined method for the barrier layer removal were developed.
Keywords: aluminum, electrochemical anodization, porous alumina, barrier layer, membrane, nanostructured material.
DEVELOPMENT OF RATIONAL METHOD FOR THE SYNTHESIS OF NANOCRYSTALLINE Fe MOLYBDATES (3+) BASED ON THE SYSTEM Fe2(SO4)3 –Na2CO3 –MoO3 – 444 page.
G.K. Shurdumov, Z.A. Abazova, Y.L. Kardanova, B.K. Shurdumov
Abstract: The paper presents theoretical and experimental data on the development of a rational method for producing powders of nanocrystalline molybdates (3+) at a relatively low temperature (600ºC) in a relatively short time (40 min) with the yield of 99,85% of the basic substance of the brand «h.ch».
Keywords: Fe2(MoO4)3, nanocrystal synthesis, identification.
EVALUATION FORCES OF INTERACTION OF GOLD NANOPARTICLES AND DNA IN WATER SOLUTION – 449 page.
P.V. Komarov
Abstract: Analytical evaluation of the interaction of gold nanoparticles with a diameter of 2 fragment of deoxyribonucleic acid has been performed at conditions of aqueous solution.
Keywords: gold nanoparticle, DNA, aqueous solution.
THE CHARTS OF CLUSTERIZATION AND NON-EQUILIBRIUM CRYSTALLIZATION OF ALLOYS OF EUTECTICUM TYPE – 4 page.
V.D. Aleksandrov, O.A. Pokyntelytsia
Abstract: The charts of clusterization of liquid and its subsequent crystallization are obtained cooling alloys with a limit solubility and without mutual solubility of components. It is shown that the transition from a binary solution of liquid to the solid phase occurs in two parallel lines as in the pre- and in hypereutectic areas. The dynamics of change of the cluster state in the course of fusion is analyzed as well as near-equilibrium crystallization and non-equilibrium crystallization from the supercooled metastable state.
Keywords: fusions, the binary system, alloys with limited solubility, alloys without mutual solubility of components, clustering, equilibrium and non-equilibrium crystallization, solid solutions, eutectic.
THERMODYNAMICS ANALYSIS OF INFLUENCE OF VACANCIES ON THE INTERPHASE SURFACE ENERGY AND ENTALPY OF CRYSTALLIZATION AT FORMATION OF CRYSTAL NUCLEI FROM A LIQUID PHASE – 10 page.
О.V. Aleksandrova
Abstract: Dependences of thermodynamics parameters of crystallization (entropy, enthalpy and the interphase surface energy) from the concentration of vacancies are in-process set. The analysis of energy of Gibbs is carried out for forming critical nuclei.
Keywords: energy of Gibbs, to entropy, enthalpy, the interphase surface energy, crystal nuclei, vacancies, critical nuclei.
THE PRODUCTION OF 3-D IMAGES OF THE CHROME NANOCOATING ON THE GLASS SUBSTRATE AND THE MEASUREMENT OF THE CURRENT-VOLTAGE CHARACTERISTICS – 14 page.
A.S. Antonov, T.Yu. Zykov, E.A. Voronova, N.Yu. Sdobnyakov,P.S. Kutilin, A.S. Mikhailov, O.V. Mikhailova
Annotation: In this paper, we have been analyzed the 3-d images of the chrome nanocoating on the dielectric substance (glass), which were obtained using by the scanning tunneling microscope and measured the current-voltage characteristics.
Keywords: chrome nanocoating on the glass substrate, 3-d images, scanning tunneling microscopy (STM), the current-voltage characteristic.
TEMPERATURE CONTRIBUTION OF INTERFACE ENERGY OF THE LOW DEMENSIONAL METALLIC SISTEMS ON DIFFERENT BOUNDARIES – 20 page.
L.P. Arefjeva, I.G. Shebzukhova
Abstract: Electron-statistical method by Frenkel-Gambos-Zadumkin has been modified to determine the temperature dependence of interface energy of low dimensional metallic system on the interface with different surrounding. The temperature contribution of interface energy, which caused by changing the Fermi energy, has been estimated. The temperature and the dimensional dependences of temperature contribution of rhodium have been shown for the interfaces thin films – vacuum and nanopartical – self-melt.
Keywords: interface energy, temperature dependence, thin films, nanopartical, rhodium.
METHOD OF OBTAINING THIN WIRE FROM ALUMINUM ALLOY Al – 14%Cu – 7%Ce – 29 page.
E.A. Babich, M.A. Zhuravleva, A.A. Mogucheva
Abstract: The influence of equal channel angular pressure on the microstructure and mechanic properties of aluminum alloy Al – 14%Cu – 7%Ce, the influence of dragging on the microstructure and failure surface of wire samples of aluminum alloy Al – 14%Cu – 7%Ce was study.
Keywords: aluminum alloys, microstructure, equal channel angular pressure, mechanic properties, dragging, deformation.
RELATION BETWEEN FRACTAL DIMENSION AND SURFACE ROUGHNESS FOR THE COPPER SAMPLES – 33 page.
Yu.V. Brylkin, A.L. Kusov
Annotation: Microscopic characteristics of copper surfaces with different roughness were produced using scanning tunnel microscope and fractal analysis.
Keywords: fractal, scanning tunnel microscopy, surface topology.
THE EVALUATION OF THE TUNNELING MAGNETORESISTANCE MANGANITE-PMMA COMPOSITES – 39 page.
A.V. Vasiliev, A.A. Eliseev, E.O. Anohin, L.A. Trusov
Annotation: Lanthanum-strontium manganite containing composites were synthesized by a warm pressing technique. The LSMO precursor was prepared by modified sol-gel method. Samples showed two types of magnetoresistance effect, tunnel, due to composite structure, and colossal, due to LSMO properties.
Keywords: composite materials, magnetoresistance, grain boundaries, tunneling.
EVALUTION OF THERMODYNAMIC CHARACTERISTICS OF METAL NANOCLUSTERS VIA MOLECULAR DYNAMICS DATA – 46 page.
S.A. Vasilyev, O.D.O. Obies, V.M. Samsonov
Abstract: Molecular dynamics results on transition metal nanoclusters were used to calculate the enthalpies of melting and sublimation. The values for the sublimation enthalpies (heats) demonstrate a good agreement with the tabulated values for the corresponding bulk phases, whereas the melting enthalpies (heats) are 2-3 times less than the corresponding tabulated values that may be interpreted as a demonstration of the corresponding size effect.
Keywords: nanoclusters of transition metals, enthalpy of melting, enthalpy of sublimation, molecular dynamics, tight-binding potential.
THE INTERFACE BOUNDARY ROLE DURING THE HEAT CAPACITY CALCULATIONS OF CU NANOCLASTERS SYNTHESIZED FROM GAS PHRASE – 52 page.
Yu.Ya. Gafner, I.V. Chepkasov
Annotation: Using molecular dynamics and modified tight-binding potential, the heat of Cu nanoclusters synthesized from the gas phase has been studied. It was shown that the interface boundary in agglomerated clusters cannot be the main reason of the significant growth of the capacity of compactioned nanomaterial, pointed in a lot of researches.
Keywords: condensation, computer modeling, copper, nanoclusters.
INFLUENCE OF DISORDER ON STRUCTURE IN SMALL ALUMINIUM CLUSTERS IN THE COURSE OF THERMAL PROCESSING – 60 page.
Yu.Ya. Gafner, V.S. Baydyshev
Annotation: The method of molecular dynamics and modified tight-binding potential (TB-SMA) were used to investigate influence of the disorder degree in nanocompacted aluminium (mean cluster diameter 3 nm) on formation of crystal structure in the course of heat treatment. It is shown, that under the influence of the temperature factor there is a transition from initial FCC phases in other structural modifications, including with pentagonal symmetry.
Keywords: computer simulations, molecular dynamics, tight-binding, nanocompacted matter, nanoclusters, aluminium.
QUANTITATIVE CORRELATION «STRUCTURE OF ALKYNES C2H2 – C9H16 – THE HEAT OF VAPORIZATION » – 67 page.
V.V. Grebeshkov, V.M. Smolyakov
Abstract: For series alkynes CnH2n-2 based on group additive method (which based on the first environment of atoms), one obtained 8-constant additive scheme of calculation of their physical and chemical properties. It is shown that within the accepted classification of structural elements in the molecules of alkynes demonstrate a linear relationship. According to the obtained formula, numerical calculations of the heats of vaporization at normal boiling point Hvap of alkynes C2H2 – C9H16 not studied experimentally were carried out.
Keywords: additive schemes, alkynes, the heat of vaporization, multiple non-bonded interactions, additive-group method.
QUANTUM-CHEMICAL MODELING OF BISMUTH’S HYDROGENATED CLUSTERS – 73 page.
E.N. Gribanov, O.I. Markov, Yu.V. Hripunov
Abstract: The paper presents the results of calculations of structure and energy parameters of BinHm nanoclusters by quantum-chemical methods.
Keywords: cluster, bismuth, quantum-chemical simulation.
ON CONTRIBUTION OF TRUE SECONDARY ELECTRONS INTO THE IMAGE FORMATION IN ELECTROOPTICAL CONVERTERS – 79 page.
V.N. Grinyuk, O.V. Gudieva, V.A. Sozaev
Abstract: The paper is aimed on refinement of the theory of originating of true secondary electrons in shooting oxide structure Al2O3 and on estimation of contribution of such electrons into the resolving ability of images in electrooptical converters. The conclusion on the decreasing resolving parameter ΔR̅i with decreasing thickness of structure and initial energy at increasing coefficient of electron multiplication βi = 1,1 ÷ 2,0 has been drawn on the basis of dependence of relative tailing of electron energies on the thickness of structure and on the initial energy. Obtained data are useful at choosing material of the structure in the conditions of processes of originating of true secondary electrons.
Keywords: aluminum oxide, shooting film, resolving ability.
ASYMMETRIC IMPURITY SEGREGATION IN MULTI-LAYERED FILMS -84 page.
I.M. Davydova, T.N. Melnik, V.M. Yurchenko
Abstract: Peculiarities of segregation of impurities at the boundaries of a thin film separating two different solid materials are considered. Theoretical and numerical analysis of kinetics of impurity redistribution within the film and at the boundaries has been carried out. Subject to the energy of interaction of the impurity atoms with the boundaries, the initial impurity concentration and temperature, the criteria of realization of different variants of segregation were ascertained.
Keywords: diffusion, weak solution, impurity segregation.
SYNTHESIS OF URANIUM OXIDE NANOCLUSTERS ON THE SURFACE OF OXIDIZED ALUMINUM – 92 page.
А.P. Zajogin, D.S. Umriko, Е.V. Vileishikova, А.I. Komyak, S.D. Umreiko
Abstract: Deposition of the products from photocondensation of acetone and uranium on the surface of oxidized aluminum with the use of hydrogen peroxide has been studied by the methods of electronic and IR absorption. It has been demonstrated that in the process of deposition the sexavalent uranium peroxide nanoclusters, strongly bonded to the substrate, are formed. Heating of the substrate and of the deposited uranium peroxide to 400 – 450 °C offers the production of the β–UO3– type uranium oxide and to 500 – 600 °C – of different forms of U3O8.
Keywords: spectral analysis, uranium complexes, uranium perchlorate, band intensity, uranium oxides, photocondensation of acetone.
BIOLOGICAL ACTIVITY OF SULFUR NANOPARTICLES OBTAINED FROM SODIUM POLYSULFIDE AQUEOUS SOLUTIONS – 98 page.
R.M. Zaynitdinova, A.N. Khusainov, L.R. Zaripova, I.A. Massalimov, A.G. Mustafin
Abstract: Studied the process of the formation of nanoparticles sulfur obtained by mixing polysulfides with of organic and inorganic acids solutions. We revealed a significant acceleration of the growth of plants with the introduction of nanoparticles sulfur in composition with alcohols and glycols, the optimal concentration of preparation, providing the maximal growth of shoots up to 58% within 3 days of their vegetation.
Keywords: sulfur, polysulphides, nanoparticles, biological activity.
NANOPHOSPHORS ON THE BASIS OF TR SILICATES – 104 page.
M.G. Zuev, S.Yu. Sokovnin, V.G. Il’ves
Abstract: Phosphors Sr2Y8Si6O26 :(0,15)Eu are received in the form of micro and nanopowders (NP). It is established that upon transition from micro- to NP, there is a modification of an vibration range of nanosamples: density of oscillatory conditions is impoverished. Width of the forbidden zone of silicates increases upon transition from micro to a nanocondition. In a range of a luminescence of nanophosphors there is a broadening of lines of a luminescence and change of their intensity.
Keywords: nanoamorphous phosphor, electronic beam, spectral-luminescent properties.
A THERMODIFFUSION INFLUENCE ON THE THERMAL LENSE RESPONSE IN A LIQUID DISPERSIVE MEDIA – 112 page.
V.I. Ivanov, G.D. Ivanova, V.K. Khe
Annotation: The stationary thermal lens response in thin layers of two component medium is analyzed. It is showed thermodiffusion can strongly influences on the thermal lens itself and the transmittance coefficient of medium.
Keywords: thermal lens, thermal diffusion, two-component medium, self-action of light.
DUFOUR EFFECT IN A DISPERSIVE LIQUID-PHASE MEDIUM IN THE GAUSSIAN BEAM FIELD – 116 page.
V.I. Ivanov, A.I. Livashvily
Abstract: The effect of thermal radiation produced when the transparent dispersion medium is under the Dufour effect is analyzed theoretically. Analytical expression describing the dynamics of the medium temperature is received.
Keywords: Dufour effect, electrostriction nonlinearity, dispersed liquid-phase medium, thermal self-action of radiation.
ELECTRICAL CONDUCTIVITY OF BORATE-BARIUM GLASS C78-5 IN THE EDUCATION AND GROWTH OF NANOCRYSTALS – 120 page.
A.M. Karmokov, Z.V. Shomakhov, O.A. Molokanov
Abstract: The temperature dependence and kinetics of changes in the electrical conductivity at a constant temperature annealing of borate-barium glass C78-5 is investigated experimentally. The values of the activation energy of electrical conductivity in different temperature ranges corresponding to different mechanisms of conductivity are found. It is established that during isothermal annealing conductivity of glass increases the higher, the higher is the temperature of annealing.
Keywords: isothermal annealing, an electrical conductivity kinetics, borate-barium glass, structural transmutations, a specific conductivity, phase formation, conductivity activation energy.
SURFACE TENSION OF A CYLINDRICAL SURFACE – 124 page.
E.V. Kishtikova, S.Sh. Rekhviashvili
Abstract: Analytical expressions for the size dependence of a surface tension are received in the framework of two various approaches (Gibbs theory and Van-der-Waals theory of an inhomogeneous medium) for cylindrical surface. It is shown, that the both approaches lead to a very close results. The coefficient of proportionality in A.I.Rusanov’s formula for a cylindrical surface is defined.
Keywords: thermodynamics of surface, Gibbs method, density distribution profile, size dependence of a surface tension, cylindrical surface.
HIGH-INTENSITY METHODS OF FORMATION OF THE MAX-PHASES IN ALUMINUM-BASED AND TITANIUM-BASED ALLOYS – 129 page.
Е.А. Кnestyapin, Е.А. Petrikova, Yu.F. Ivanov, A.А. Klopotov
Annotation: In work are submitted data on evolution of structure and properties of a titanic alloy of BT6 and silumin after an electroexplosive alloying and radiation by an electronic bunch. Formation the MAX -phase of structure of Ti3SiC2 and Ti3AlC is established.
Keywords: Titanium and titanium alloys, electroexplosive alloying, electron beam treatment, MAX phases.
SIMULATION OF THE COALESCENCE PROCESS OF METAL NANOPARTICLES OF DIFFERENT SHAPES – 134 page.
A.Yu. Kolosov, N.Yu. Sdobnyakov, P.V. Komarov, N.V. Novozhilov, A.N. Bazulev, D.N. Sokolov
Abstract: The simulation of the coalescence process of gold and copper nanoparticles of different shapes by Monte-Carlo method was carried out. The interaction between nanoparticles was described by many-body Gupta potential. It was found that the shape of nanoparticles significantly affects the melting point and the coalescence process. Moreover, the coalescence doesn’t happen at all at certain distances between nanoparticles of an initial configuration.
Keywords: gold nanoparticles, copper nanoparticles, coalescence, Monte-Carlo method, Gupta potential, phase transition, neck.
INVESTIGATION OF THREADLIKE AGGREGATES FORMED BY SILVER MERCAPTIDE BY LANGEVIN DYNAMICS – 146 page.
P.V. Komarov, P.M. Pakhomov, S.D. Khizhnyak
Annotation: Stability of threadlike aggregates formed from silver mercaptide has been investigated by using of the Langevin dynamics. These aggregates are presumably formed at a late stage of maturation of cysteine silver solution.
Keywords: hydrogel, computer simulations.
THE VACANCY CLUSTER IN THREADED CRYSTALS OF SILVER AZIDE – 157 page.
L.V. Kuzmina, E.G. Gazenaur, V.I. Krasheninin, E.V. Sugatov
Annotation: This paper presents the results of experimental studies of education the vacancy cluster in threaded crystals of silver azide. It is experimentally shows the role of vacancy cluster in the reactivity of these materials. Methods of time management formation vacancy cluster are proposed.
Keywords: threaded crystals of silver azide, vacancy cluster, reactivity, impurity defects, dislocations.
STRUCTURE AND MORPHOLOGY OF NANOPARTICLES OF MAGNETITE (Fe3O4) AT SORPTION OF HEXAVALENT CHROME FROM AQUEOUS SOLUTION – 161 page.
O.D. Linnikov, A.M. Murzakaev, I.V. Rodina, A.P. Tjutjunnik,
L.B. Mamtcev, N.A. Khlebnikov, A.P. Tyutyunnik
Abstract: Nanopowder of magnetite before and after sorption on it of hexavalent chrome from aqueous solution was studied by methods of X-ray analysis and electron microscopy. Obtained results testify that at sorption (chemisorption) of chrome(VI) by magnetite the formation of new phase in the form of compound body of chrome and iron occurs not in the volume of solution or onto surface of magnetite but in its thin surface layer.
Keywords: magnetite, chrome (VI), nanoparticles, sorption, X-ray analysis, electron microscopy, aqueous solution.
ON THE SIZE DEPENDENCIES OF PARAMETERS OF THE CRYSTAL-LIQUID PHASE TRANSITION -169 page.
M.N. Magomedov
Abstract: The relatively simple method for calculation of the size dependencies of the latent heat, the
volume jump and the interphases surface energy under crystal-liquid phase transition is proposed. For the calculation by this method is necessary to know of the experimental size dependencies of the melting point and the temperature of the beginning of crystallization. The method is tested for nanoparticles of Cu, Au, Al and Ni.
Keywords: melting, crystallization, latent heat of the phase transition, volume jump, nanocrystal, nanodrop, size, shape of the surfaces.
KINETICS OF THE ELECTROCHEMICAL OXIDATION OF ALUMINUM IN SULFURIC ELECTROLYTE – 176 page.
E.S. Markaryan
Annotation: It is investigated the kinetics of the growth of porous alumina by anodization in an aqueous solution of sulfuric acid. Kinetic data obtained as a result of the anodic process are extremely informative in terms of a general theory of pore formation in aluminum. It was observed to the existence of the «bifurcation point». The position the «bifurcation point» of for oxides molded at different current values has been defined.
Keywords: anodic aluminum oxide growth kinetics, the point of bifurcation.
ANALYSIS OF CREATING A MAGNETIC FIELD SENSOR BASED ON OFF-DIAGONAL MAGNETOIMPEDANCE – 180 page.
A.T. Morchenko, L.V. Panina
Annotation: Effect of a magnetic impedance (MI) is a very promising for the creation of high performance magnetic sensors. For sensor applications, off-diagonal configuration is preferable when the MI element is excited by ac current and the output is detected from the coil. In this case, the signal is linear on the external field. The paper analyses the work of the magnetic field sensor on amorphous microwire with off-diagonal configuration of the sensor element.
Keywords: off-diagonal magnetoimpedance, magnetic field sensor, amorphous microwire, pulse excitation of the sensor element.
EVOLUTIONARY SEARCH FOR OPTIMAL STRUCTURES OF THE SMALL GOLD-SILVER CLUSTERS WITHIN THE TIGHT-BINDING APPROXIMATION – 187 page.
V.S. Myasnichenko
Abstract: The structures of the global minima for AunAg14-n clusters all the compositions were calculated. Atomic interaction was modeled by a many-body Cleari-Rosato potential. The combination of genetic algorithm with simulated annealing method used to search for global minima. Results are six possible configurations optimal geometric isomers.
Keywords: cluster, nanoalloy, structure, optimization, gold, silver.
QUANTITATIVE CORRELATION «STRUCTURE ALLENES C3H4 –C10H18 – THE HEAT OF VAPORIZATION » – 194 page.
D.Y. Nilov, V.M. Smolyakov
Abstract: For series allenes CnH2n-2 based on group additive method (witch basis on the first environment of atoms) is obtained 9-constant additive scheme of calculation of their physical and chemical properties. It is shown that within the accepted classification of structural elements in the
molecules of allenes have a linear relationship. According to the obtained formula, numerical calculations of the heats of vaporization at normal boiling point Hvap allenes C3H4 –C10H18 not studied experimentally.
Keywords: additive schemes, allenes, the heat of vaporization, multiple non-bonded interactions, additive-group method.
COMPARATIVE STUDIES OF SOLID SOLUTION Li0,125Na0,875NbO3 SYNTHESIZED AT ATMOSPHERIC AND HIGH PRESSURES – 200 page.
M.N. Palatnikov, V.V. Efremov, O.V. Makarova, N.V. Sidorov
Abstract: Structural and electrical properties of a solid solution (SS) of Li0,125Na0,875NbO3 are studied. Synthesis of the solid solution of Li0,125Na0,875NbO3 under high pressure achieves more highly ordered structure. This increases the dielectric constant and ionic conductivity while decreasing the activation enthalpy of ion transport compared with the solid solution of Li0,125Na0,875NbO3 obtained by the usual ceramic technology.
Keywords: ferroelectric solid solutions, pressure-thermal synthesis, the usual ceramic technology, Raman scattering, admittance diagrams, the structural ordering of the ionic conductivity, and the enthalpy of activation.
THE USE OF THE OFF-DIAGONAL MAGNETOIMPEDANCE PHENOMENON TO BUILD SENSORS OF WEAK MAGNETIC FIELDS AND CURRENTS – 210 page.
L.V. Panina, N.A. Yudanov, A.T. Morchenko, V.G. Kostishyn, D.G. Krutogin, A.A. Rudenok
Annotation: In the present work, the off-diagonal sensor design was advanced by utilising a complex waveform excitation produced by a microcontroller and applied to a multiple wire magnetoimpedance element. For optimised excitation the field resolution of about mV/Oe was achieved. The concept of microcontroller driven sensor element could be attractive for the development of intellectual sensors.
Keywords: off-diagonal magnetoimpedance, magnetic field sensor, amorphous microwire, pulse excitation.
APPLICATION OF THE EFFECTIVE IMPEDANCE METHOD FOR IN SITU ELLIPSOMETRIC ANALYSIS OF MAGNETIC FILMS – 219 page.
L.V. Panina, A.T. Morchenko, V.G. Kostishyn, D.N. Chitanov, R.D. Piliposyan
Abstract: The technique of effective surface impedance is proposed and applied as useful tool for non-destructive in situ characterisation of optical and magneto-optical parameters of magnetic heterostructures. Standard ellipsometry analysis requires the model response to be calculated from every layer in the structure. For any ellipsometry investigations a proper choice of a physical model is important for solving the inverse problem by a regression method. Reasonable approximations used for in situ ellipsometry monitoring are assumptions of a constant rate of layer growth and stable optical parameters. In this case a method of a pseudosubstrate is used which approximates the underlying structure as a single interface (so called virtual interface), rather than tracking the entire sample history.
The virtual interface is placed at some level and growth is modelled on this interface with no knowledge retained for the underlying structure.Magneto-optical spectra were detected in the configuration of equatorial Kerr effect which is fully compatible with the ellipsometry measurements. The method is successfully used to analyse Co, Fe/Si/glass films.
Keywords: effective impedance, in situ ellipsometry, magnetic films, kerr effect, magneto-ellipsometry, multilayers, pseudosubstrate, virtual interface.
STRUCTURE OF SMALL CLUSTERS OF TITAN TiN ( N = 2 ÷ 15) – 231 page.
N.A. Pankin
Abstract: The study was performed of the structure of free clusters of titanium TiN ( N = 2 ÷ 15) by means of molecular dynamics using a many-particle cooperation in the tight-binding model. The values of coordination number, length, binding energy and frequency of the studied clusters are found.
Keywords: clusters of titanium, molecular dynamics method, many-particle potential, atomic structure.
SYNTHESIS OF THE ZINC OXIDE NANOCLUSTERS DOPED WITH COPPER FROM ORTHOPHOSPHATE SALTS IN POROUS SAMPLES ON LASER ABLATION – 239 page.
М.P. Patapovich, N.H. Trinh, Le Thi Kim Anh, A.P. Zajogin
Abstract: Spectroscopic studies of the surface laser plasma formed close to the porous body containing nanoquantities of different zinc and copper salts under the effect of two successive pulses have been performed. The potentialities for the development of the metal oxide nanoclusters formation methods have been demonstrated. It has been shown that, depending on the concentration of the starting metals in the solutions used, one can vary the quantity and composition of the clusters.
Keywords: nanoclusters, pulsed laser sputtering, surface laser plasma, laser spark spectrometry, metal oxides, double laser pulses.
AN ADEQUATE POTENTIAL BASED ON MOLECULAR INFORMATION: SELECTION AND APPROBATION – 245 page.
G.G. Petrik
Abstract: The results are given obtained due to a new approach to description of the potential curves shapes, defined links of the special point coordinates for the curves with the critical parameters and the analytical and calculation possibilities of the molecular model of spherical shells. It is shown that an adequate potential of spherical shells is formed simply by the most general control factor of the model – the rigidity of the shell. The method of selection in the family of the potentials of the adequate potential-analogue is supposed.
Keywords: intermolecular interaction, interacting point centers, spherical shells, adequate potentials, parameters, special points of the curves.
INVESTIGATION INTO THE AND RADICAL FORMATION PROCESSES IN THE PLASMA DUE TO DEFOCUSING OF DOUBLE LASER PULSES INCIDENT ON OXIDIZED ALUMINUM – 261 page.
S.V. Protsenko, Aljdigaui Haidar Ali Rai, A.R. Fadaijan, E.S. Voropay, А.P. Zajogin.
Annotation: The influence of the laser-pulse radiation defocusing on the formation of the desired component and charge composition of the surface plasma is studied using the laser spark spectrometry (LSS-1 spectrometer). The possibility for increasing the portion of AlO and AlN radicals in the plasma when the aluminum target is subjected to the effect of the successive defocused double laser pulses is shown.
Keywords: spectral analysis, AlO and AlN radicals, double laser pulses, laser ablation, plasma processes.
STRUCTURE OF COMPOSITE COATINGS IMMISCIBLE COMPONENT OF Cu-Mo, RECEIVED ELECTROEXPLOSIVE SPRAYING AND A MODIFIED HIGH INTENSITY ELECTRON BEAM – 267 page.
D.A. Romanov, O.V. Olesyuk, E.A. Budovskikh, V.E. Gromov, Yu.F. Ivanov, A.D. Teresov
Abstract. The studies of the phase and elemental composition, condition of the defect substructure of the surface layer of electrical grade copper M00 subjected electroexplosive composite coating deposition systems Cu-Mo and subsequent exposure of high-intensity pulsed electron beam. Identified modes of electron-beam processing, enable the development of compact, high-gloss surface layers with submicron and nano-crystalline structure based on molybdenum and copper.
Keywords: electroexplosive spraying, electron beam processing, pseudo-alloy, molybdenum, copper, structure.
USE OF EXPLOSION ENERGY FOR STRENGTHENING WORKING BODIES OF SOIL-CULTIVATING MACHINES – 274 page.
V.V. Semashko, L.V. Sudnik, A.F. Ilyushchenko
Abstract: The research has defined technological methods that combine energy use of explosives and traditional methods of surface treatment (quenching and tempering) to improve the parameters of agricultural machinery.
Keywords: endurance, strength, resilience, hardness, tribological surface, microstructure, laminated material, high-energy loading, shock wave of high intensity.
DRIVING FORCES FOR SURFACE SEGREGATION IN THE Cu-Ge AND Cu-Mn ALLOYS – 282 page.
I.N. Sergeev, K.Ch. Bzhihatlov
Abstract: In the approximation of the combined Langmuir – McLean model considered the driving forces for surface segregation in (111)Cu – 2 at. %Ge and (100)Cu – 4 at.%Mn single crystals. Model predictions are compared with the temperature dependence of the surface segregation obtained by AES. The influence of the type used Langmuir – McLean isotherm on the accuracy of prediction has been estimated.
Keywords: Cu-Mn and Cu-Ge single crystals, Langmuir – McLean model, Auger electron spectroscopy, surface segregation, segregation energy.
ESTIMATION OF THE SURFACE TENSION OF Cu- 2 AT. %Ge AND Cu – 4 AT. %Mn SOLID SOLUTIONS, USING DATA OBTAINED BY AUGER ELECTRON SPECTROSCOPY – 290 page.
I.N. Sergeev, K.Ch. Bzhihatlov
Abstract: In the regular solution approximation with the experimental values of the composition of the surface, obtained by Auger electron spectroscopy, calculated the temperature dependence of the surface tension of (111)Cu – 2 at. %Ge and (100)Cu – 4 at.%Mn single crystals. Influence of the nature of the interatomic interactions on the segregation effect of reducing the surface tension is shown.
Keywords: Cu-Ge and Cu-Mn solid solution, surface tension, surface segregation, Auger electron spectroscopy.
THE IMPACT OF THERMAL CYCLING ON THE REPEATABILITY OF TEMPERATURE DEPENDENCEE CONDUCTIVITY OF NANOSTRUCTURED SnO2 FILMS – 296 page.
A.V. Smirnov, A.I. Grebennikov, I.V. Sinev, V.V. Simakov
Abstract: The purpose of the present study is temperature dependence of the conductivity of nanostructured tin dioxide films on temperature after treatment in an argon plasma. It is shown that thermal cycling conducted after treatment in an argon plasma returns temperature dependence of conductivity in the initial state.
Keywords: tin dioxide, temperature dependence of conductivity, plasma processing, thermal cycling.
THE INVESTIGATION OF THE STRUCTURAL CHARACTERISTICS OF THE METAL NANOCLUSTERS IN MELTING/CRYSSTALLIZATION PROCESS USING MANY-BODY GUPTA POTENTIAL – 301 page.
D.N. Sokolov, A.P. Andriychuk, M.P. Khazitonova, I.V. Kartashov, P.V. Komarov,
N.Yu. Sdobnyakov
Annotation: In this work the investigation of the structural characteristics of the gold nanoclusters in the melting/crystallization process has been carried out. The possibility of the determination of the phase transition temperature has been shown by the temperature dependence of the mean value of the first coordination number. The process of the forming FCC/HCP structures for gold nanoclusters during melting and crystallization has been described.
Keywords: gold nanoclusters, melting and crystallization, Monte-Carlo method, Gupta potential, first coordination number, local density, FCC structure, HCP structure.
FORMATION OF HIGH TRIBOMECHANICAL PROPERTIES FILMS BASED ON Ti1-xAlxN BY OPTIMIZING THE PULSED MAGNETRON POWER SYSTEMS – 317 page.
T.O. Soshina
Abstract: The effect was investigated of the power pulsed magnetron system on the composition, structure, physico-mechanical and tribological properties of the films on the based on Ti1-x AlxN. At the optimum value of the power polycrystalline film was produced with a unique set of mechanical and tribological properties.
Keywords: pulsed magnetron sputtering, magnetron power system, the phase composition, the chemical composition, microstructure, mechanical properties, tribological properties.
SPECTRUM OF ENERGY OF TETRAHEDRAL CRYSTALS WITH LOCAL DEFECTS. COMPARATIVE CALCULATION WITHIN THE FRAMEWORK OF MODELS OF ORBITALLY-STOICHIOMETRIC CLUSTER AND OF MOLECULAR CLUSTER WITH COMPENSATION OF BROKEN VALENCIES – 325 page.
A.M. Stebenkov, N.A. Stebenkova
Abstract: The spectrum of one-electron states (SOS) of covalent and ionic-covalent crystals (C, Si, Ge, BN, BP, AlN, AlP and GaP) was calculated under the MNDO scheme with a usage of symmetrically extended models of a) an orbital-stoichiometric cluster and b) a molecular cluster with closure of broken valences by hydrogen atoms. The calculations were carried out for ideal crystals as well as those with substitution local defects. It was shown, that both models lead to qualitatively coincident results.
Keywords: spectrum of energy, quantum-chemistry calculation, covalent crystals, local defects in solid body.
ANALYSIS OF PROBABLE MECHANISM OF PARTIAL METAL MELT STRATIFICATION IN CAPILLARS – 333 page.
N.P. Ouglev
Abstract: Review of experiments on stratification of binary metal melts in capillaries has been performed. Considering old results and new experimental data represented in this paper, conclusion has made that effect of the layering can be explained only with totally new approach to structure and properties of liquid metal melts and/or any liquid in general.
Keywords: stratification, capillaries, sedimentation rate, clusters, liquid melt structure.
MECHANISM OF PARTIAL METAL MELT STRATIFICATION IN CAPILLARS – 343 page.
N.P. Ouglev
Abstract: Experimental results of diameter, inclination, angle and length effects on metal melt stratification rate are represented. These relationships determined experimentally were compared with relationships obtained on the basis of simple hydrodynamics expressions. It has been approved that mechanism of the layering is not related with convection inside metal sample. Experimental data and theoretical evaluation show that most adequate explanation of the stratification process can be produced with the assumption of special properties of single-atom surface layer of liquid melt having characteristics of ideal gas in interphase space between capillary inner wall and liquid sample.
Keywords: stratification, capillaries, convection layering, two-dimension flow, two-dimension ideal gas, metal melts.
HETERO-GRAPHENE AND HETERO-DIAMOND PHASES SYNTHESIZED IN THE B – C – N SYSTEM UNDER PRESSURE – 353 page.
V.P. Filonenko, I.P. Zibrov, V.A. Sidorov, M.V. Trenihin
Abstract: The phases formation in the B – C – N system at thermobaric treatment of mixtures of carbon nitride or melamine with boron has been studied. It was found that in the pressure range of 4-8 GPa graphite-like particles were formed first. Then their crystal lattice can be transformed into the cubic one. Hetero-graphene and hetero-diamond phases have a basic structure of boron nitride. Around ten percent of carbon atoms are homogeneously distributed in this lattice replacing the boron and nitrogen. The proposed methodology allows the synthesis of nano- and micro-sized particles of BCN phases.
Keywords: High-pressure, hetero-graphene phase, hetero-diamond phase, carbon nitride.
CALCULATING THE MAGNETIC CONTRIBUTION TO THE HEAT CAPACITY OF THE QUASIONEDIMENSIONAL ISING MAGNETICS – 362 page.
E.V. Shabunina, M.E. Shabunin, D.V. Spirin, V.N. Udodov
Annotation: Effect of temperature, interactions up to three neighbors and sizes on heat capacity of small magnetic systems within the one-dimensional Ising model by Monte Carlo method was studied.
Keywords: heat capacity, Ising model, one-dimensional chain, magnet, quasionedimensional compounds.
PHASE COMPOSITION AND GRAIN STRUCTURE OF RAPIDLY SOLIDIFIED EUTECTIC ALLOY Sn – 32 WEIGHT %Cd – 370 page.
V.G. Shepelevich
Annotation: Rapidly solidified eutectic alloy Sn – 32 weight %Cd consists of solid tin and cadmium solutions. There is microcrystalline structure with average size of grains less than 1µm. Forming of structure in foils is caused with spinodal decomposition of liquid solution and next crystallization of liquid phases, richen by tin and cadmium.
Keywords: rapidly solidification, tin, cadmium, dispersive particles, foil.
TWO-LAYER NANOSTRUCTURED MEMBRANES, SYNTHESIZED BY ELECTROCHEMICAL ANODIZATION IN OXALIC ACID ELECTROLYTE – 376 page.
D.L. Shimanovich
Abstract: Technological methods for the formation of 73 – 216µm thick porous two-layer Al2O3 membranes with ~55 nm pores diameters by a two-sided through anodization in oxalic acid electrolyte and subsequent bipolar anodization were designed. High shape stability and crack resistance after high-temperature (>500°C) treatments, ~ 20 – 23 W/m•K thermal conductivity, ~ relative dielectric constant were obtained.
Keywords: aluminum, electrochemical anodization, porous alumina, barrier layer, bipolar anodization, membrane, nanostructured material.
STUDY OF THROUGH-THE-THICKNESS NANOPOROUS ALUMINA STRUCTURES WITH IMPLANTED ALUMINUM ELEMENTS – 281 page.
D.L. Shimanovich
Abstract: Technological features for the formation of 5-100µm thick implanted aluminum elements and free anodic nanoporous Al2O3 structures simultaneously by a two-sided through electrochemical anodization were studied. It was proved that the thickness of the free alumina plate, the distribution and sizes of the interconnection system in its volume were varied by technological conditions.
Keywords: aluminum, electrochemical anodization, nanoporous alumina, barrier layer, two-sided through anodization, bipolar anodization, implanted element, interconnection system.
ELECTROCHEMICAL PRODUCTION OF NANOSTRUCTURED MATERIALS BASED ON NICKEL – 385 page.
A.V. Shmigel, P.A. Tichonov, M.Yu. Arsent’ev, A.E. Lapshin
Annotation: The report given the results of the preparation of nanoparticles of nickel hydroxide by an electrochemical method, in distilled water and potassium hydroxide, using nickel electrodes. The novelty of the work lies in systematic studying of the preparation process of the preparation of nickel hydroxide nanoparticles by an electrochemical method. The particle size was determined by dynamic light scattering and X-ray diffraction analysis.
Keywords: nanostructured materials, nanoparticles of nickel hydroxide, electrochemistry.
PREPARATION AND INVESTIGATION OF METALLIC SILVER NANOPARTICLES BY ANODIC OXIDATION – 390 page.
A.V. Shmigel, P.A. Tichonov, M.Yu. Arsent’ev, I.A. Drozdova
Abstract: The article provides the results of the electrochemical preparation of metallic silver nanoparticles. The process was carried out in distilled water using silver electrodes. The laser analyzer determined the size of metallic silver particles as 3-35 nm. Average particle size was obtained with an electron microscope was 10 nm.
Keywords: Nanostructured materials, silver nanoparticles ,electrochemistry.
СERAMICS BASED ON COPRECIPITATION OF NIOBIUM AND TANTALUM PENTOXIDE: STRUCTURE AND PROPERTIES – 397 page.
O.B. Shcherbina, V.V. Efremov, M.N. Palatnikov, S.M. Macloboeba
Abstract: Using methods of probe microscopy and impedance spectroscopy, the structure, mechanical and electrophysical properties of ceramics on the basis of coprecipitated pentoxide Nb2(1-y)Ta2yO5 were investigated.
Keywords: coprecipitated pentoxide, ceramics, micro- and nanostructures, microhardness, Young’s modulus, probe microscopy, impedance spectroscopy, mechanical and electrical properties.
SOME QUESTIONS OF PHYSICS OF STRENGTH OF METAL NANOSTRUCTURES – 408 page.
V.M. Yurov, V.Ch. Laurinas, S.A. Guchenko
Annotation: In the work of the equation is obtained that relates the limit of fluidity of a crystal with its limit of elasticity. The equation is analogous to the known equations of the Hall-Petch. It is shown that, beginning with the critical size of nanocrystal, increase its hardness is replaced by the opposite effect. For a number of metals are given the value of the critical size of nanocrystal.
Keywords: strength, nanostructure, yield strength, tensile elasticity, dimensional effect, thermodynamics.
THE ANALYSIS OF GIBBS ENERGY CHANGE AT EQUILIBRIUM CRYSTALLIZATION OF ALLOYS OF EUTECTIC TYPE BY METHODS OF GEOMETRICAL THERMODYNAMICS – 4 page.
V.D. Aleksandrov, N.V. Shchebetovskaya, O.V. Aleksandrova, O.A. Pokyntelytsia
Abstract: Using geometrical thermodynamics methods possible versions of Gibbs energy are found and their dependence on temperature and concentration of components in a diphasic zone at equilibrium crystallization of alloys of eutectic type.
Keywords: equilibrium crystallization, two-component alloys, geometrical thermodynamics, Gibbs energy.
MOLECULAR-DYNAMICS SIMULATION OF EPITAXIAL GROWTH OF NANOSIZED LEAD HETEROSTRUCTURES ON NICKEL – 10 page.
A.G. Bembel, S.A. Vasilyev, V.M. Samsonov
Abstract: Epitaxial growth of nanosized Pb heterostructures (islands) on faces (100) and (111) of Ni was simulated using the isotheral molecular dynamics. Specific features were revealed of the epitaxy in metallic systems in comparison with Lennard-Jones systems. Configurations of islands, obtained by the epitaxial growth were compared with those obtained using the crystallization of nanodroplets on faces (100) and (111) of monocrystalline Ni. Autoepitaxy of Ni was also simulated.
Keywords: epitaxy, nanosized heterostructures, Pb islands on Ni, isothermal molecular dynamics.
THE INFLUENCE OF SEGREGATION ON MORPHOLOGY OF THE (100) CU-4 AT. % MN ALLOY SURFACE -19 page.
K.Ch. Bzhihatlov
Abstract: The influence of thermostimulated segregation on morphology of Cu-22,5 at. % Mn alloy surface was investigated by low energy electron diffraction means. Surface structural perfection of the alloy is estimated by the diffraction reflection.
Keywords: low energy electron diffraction, diffraction peak profile, thermostimulated segregation, Cu – Mn alloy.
RESEARCH OF SURFACE TENSION OF CATALYTIC CLUSTERS ON SUBSTRATE (Fe- SiO2) – 26 page.
S.V. Bulyarsky, A.V. Tsygantsov
Abstract: We investigate the temperature dependence of the surface tension of supported nanoclusters in the gas medium and the influence of some parameters on the cluster size distribution.
Keywords: catalyst, Singular catalyst, Plural catalystscarbon nanotubes, surface tension.
PRODUCTION AND PROPERTIES OF IRON NANOPOWDERS – 30 page.
E.E. Vladimirova, V. Vassil’ev, A. Nosov, T. Karpova
Abstract: Using the method of thermal hydrolysis of six-water chloride of iron in the regenerative atmosphere, the powders of iron were obtained consisting of particles in the size range of 75-150 nanometers. The morphology and magnetic properties of the obtained alloy are investigated.
Keywords: thermohydrolysis, nanoparticles, powders, iron, morphology.
POSSIBILITY OF NEW DATA CARRIERS PRODUCTION ON THE BASIS OF Ni NANOCLUSTERS -35 page.
J.J. Gafner, J.V. Golovenko, S.L. Gafner
Abstract: The possibility of Ni nanoclusters is analyzed to be used as information units in the devices of memory constructed on the principle of change of the phase state. The conclusion is drawn, that prominent feature of structurization is accurately distinguishable influence of the size of a particle on its stability. The limiting nanoparticles size at which structural transition necessary for the data recording is defined.
Keywords: data recording, nanoclusters, computer simulations, molecular dynamics, phase transitions.
PRODUCTION OF THE NANOSTRUCTURED COMPOSITE POWDER MATERIALS BY HIGH-SPEED MECHANOSYNTHESIS METHOD – 42 page.
E.Y. Gerashchenkova, B.V. Farmakovsky
Abstract: The most important result of the work is the development of the controlled technological process of the nanostructured composite powder materials production. Varying the technological parameters of the material disintegrator, we can influence on the matrix reinforcing rate during the production process.
Keywords: nanostructured composite powders materials, disintegrator, mechanosynthesis.
FORMATION LAWS FOR STRUCTURAL MODIFICATIONS IN GOLD NANOCLUSTERS -50 page.
J.V. Golovenko, J.J. Gafner, S.L. Gafner
Abstract: On the basis of the tight-binding potential modeling by molecular dynamics method, structurization processes in gold clusters from 1,6 to 5,0 nanometers in diameter were investigated. Influence of crystallization on formation of the internal structure in gold nanoclusters within the limits of the canonical ensemble is investigated. Range of stability various crystal isomers are analyzed.
Keywords: computer simulations, molecular dynamics, tight-binding, FCC metals, nanoclusters, structure.
STUDY OF FORMATION OF SUPRAMOLECULAR STRUCTURES BASED ON NANOCLUSTERED POLYOXOMOLIBDATE MO138 AND CATIONIC SURFACTANT IN SOLUTION – 57 page.
K.V. Grzhegorzhevskiy, A.A. Ostroushko
Abstract: Interaction between toroidal nanocluster Mo138 and cationic surfactant tridecylpyridinium chloride in aqua solution was studied by UV-spectroscopy, FTIR-spectroscopy, dynamical light scattering – we have determined size distribution and ξ-potential of the system. Due to experimental data we have made a model, which describes interaction mechanism between Mo138 and surfactant in dependence on the component concentrations ratio. The model also has been proved by atomic force microscopy and scanning electron microscopy.
Keywords: nanocluster, surfactant, supramolecular structures, vesicle, globule, interaction model, polyoxomolibdate.
SIMULATION OF EFFICIENCY OF NANOSTRUCTURAL FILTERS FOR CLEANING OF HYDROGEN AT IONIC TRANSFER IN ELECTRIC FIELD – 70 page.
V.N. Grinjuk, O.V. Gudieva, V.A. Sozaev
Abstract: Theoretical model for estimation of the efficiency of nanostructural materials for cleaning of hydrogen from gas impurities, in conditions of applied electric field with energy of ions ranging from 2000 to 6000 eV, has been presented. The graphical dependences of reduced lengths of the free paths of ions in medium, of the permeability and of the barrier-factor of medium on the mass of entering ion and of ion of nanostructure have been plotted. It is shown, that the optimal structure for the cleaning of hydrogen is the structure Zr – 10%Nb.
Keywords: hydrogen, cleaning, gas impurities, electric field, nanostructures.
EFFICIENCY OF PROTECTION OF PHOTOCATHODE OF ELECTRONIC DEVICE BY THE BARRIER NANOSTRUCTURE ON MICROCHANNEL ELEMENT AT EXCHANGE INTERACTION IN SYSTEM ENTERING ION – STRUCTURE – 75 page.
V.N. Grinjuk, O.V. Gudieva, V.A. Sozaev
Abstract: The aim of this work was to build the correct theory of the ion transport in nanostructured materials and estimation of the protection effectiveness of the photocathode of electronic device in terms of the average free path of positive ions reducing the longevity of photocathode. The influence of the exchange of inter-ionic interactions on the effect of ion transfer has been considered for the first time and the relation for the true charge of the positive ion entering the nanostructured material has been obtained. The better fit of the data based on the proposed theory with the reference ones has been achieved. The degree of universality of the developed theory has been discussed when considering the transport of ions through any phase boundary in the applied constant electric field.
Keywords: nanostructure, microchannel element, photocathode, ionic interaction.
ENDOHEDRAL RADON-222 СОNTAINING BUCKMINSTERFULLERENE DERIVATIVES С60 AND С80 AS NANOROBOTS-KILLERS OF TUMORS – 80 page.
Е.А. Dikusar
Abstract: The alternative technique treatment of tumor diseases – binary neutron capture therapy – can provide the utilization of radioactive isotopes, consisting inside buckminsterfullerene clusters.
Keywords: Radionuclides, buckminsterfullerenes, oncology, neutron capture therapy, nanorobots-killers of tumors, radon, L-phenylalanine derivatives.
SIMULATION OF THE SEVERE PLASTIC DEFORMATION PROCESS IN NANOCRYSTAL ON THE BASIS OF INTERMETALLIDE – 85 page.
E.A. Dudnik, M.S. Skorobogatov
Abstract: The mechanisms of structural transitions in a nanocrystal on the basis of intermetallic Ni3Al was studied by means of simulation of the process of the severe plastic deformation. For the structure analysis we used the simplexes of Voronoi-Delaunay, which allow tracing the dynamics of the formation of ordered areas in the process of deformation.
Keywords: nanocluster, severe plastic deformation.
WETTING OF ALUMINIUM FILMS ON SILICON BY TIN-STRONTIUM MELTS BEFORE AND AFTER PHOTONIC ANNEALING – 92 page.
K.M. Elekoeva, A.Z. Kashezhev, A.R. Manukyants, M.Kh. Ponegev, A.D. Prokhorenko, V.A. Sozaev
Abstract: The results of experimental study of aluminium films wetting angles (treated with the photonic annealing of various duration) on silicon by tin-strontium melts are presented. The photonic annealing of substrates is found to decrease the values of wetting angles.
Keywords: wetting, polytherms of wetting angles, tin-strontium melts, aluminum films, photonic annealing.
PHOTOCHEMICAL SYNTHESIS OF URANIUM OXIDE NANOCLUSTERS AND THEIR DEPOSITION ON THE SURFACE OF OXIDIZED ALUMINUM – 97 page.
А.P. Zajogin, D.S. Umriko, А.I. Komyak, Е.V. Vileishikova, S.D. Umreiko
Abstract: The processes of the photochemical formation of nanoclusters of the tetra- and pentavalent uranium complexes with organic ligands on light-diode irradiation (430 – 450 nm) of UO2(ClO4)3•5H2O solutions in acetone were studied by the methods of electronic and IR absorption. The possibility for deposition of the complexes of tetra- and pentavalent uranium from the photocondensation products of acetone on the porous surface of oxidized aluminum was established.
Keywords: spectral analysis, uranium complexes, uranyl perchlorate, band intensity, organic ligands, photocondensation of acetone.
A STUDY INTO THE FORMATION PROCESSES OF URANIUM NANAOCLUSTERS WITH VARIABLE VALENCE WHILE URANYL SOLUTIONS WITH DIMETHYL FORMAMIDE ARE SUBJECTED TO IRRADIATION AND DEPOSITED ON GLASS SURFACE -103 page.
А.P. Zajogin, D.S. Umreiko, А.I. Komyak, J.I. Buloichik, S.D. Umreiko
Abstract: Using the methods of electronic and IR absorption, we have studied the photochemical formation processes of the complexes between tri-, tetra-, and pentavalent uranium and organic ligands when the solutions of UO2(NO3)3•6H2O in dimethyl formamide, UO2(NO3)3•6H2O in dimethyl formamide with the addition of CCl4, and UO2(ClO4)3•5H2O in dimethyl formamide were subjected to the effect of light-diode radiation (430-450 nm). The possibility for deposition of the complexes of tetra- and pentavalent uranium on the glass surface was established.
Keywords: spectral analysis, uranium complexes, organic ligands, variable valence, photochemical cluster formation processes.
PHYSICAL AND CHEMICAL PROPERTIES OF THE AMORPHOUS NANOPOWDER Gd2O3 – 108 page.
V.G.Il`ves, M.G.Zuev, S.Yu.Sokovnin, S.A. Uporov
Abstract: By means of pulsed electron beam evaporation in vacuum Gd2O3 amorphous nanopowder was produced with a specific surface area 155 m2/g. The powder consisted of agglomerates of size from tens up to several hundred nm and aggregates formed of amorphous-crystalline particles of near spherical shape and size of 3-10 nm with very narrow size distribution. Magnetic and luminescent properties of the powder were measured at room temperature. Phase transformations in the powder are studied at heating to 1400 °C. The amorphous phase Gd2O3 was thermally stable up to temperature of 1800 °C.
Keywords: оxide gadolinium, nanopowder, pulsed electron beam, phase transformations.
PHYSICAL MODEL OF AGGLOMERATION OF THE DISPERSE PRECIOUS NOBLE METALS UNDER EFFECT OF LASER BEAM – 115 page.
Abstract: The effect of the continuous laser radiation was investigated on the mineral medium containing gold, not extracted by gravitational methods. A physical model of the gold agglomeration and concentration was put forward on the basis of theory of thermocapillary convection of disperse particles.
Keywords: laser radiation, disperse gold, defragmentation, agglomeration, surface tension, thermocapillary convection.
THE INVESTIGATION OF THICKNESS DEPENDENCES OF REFRACTIVE INDEX FOR NANOSIZED ETHANOL FILM BY ELLIPSOMETRIC METHOD – 122 page.
D.A. Kim, N.Yu. Sdobnyakov, N.V. Novozhilov, A.S. Antonov, D.N. Sokolov, E.A. Voronova, O.V. Mikhailova
Abstract: On the basis of analyzing the spectrum of the ellipsometric angles ∆ and ψ the investigation of thickness dependences of refractive index for nanosized ethanol film on silicon and glass surface using the photometric spectral ellipsometer was carried out.
Keywords: ellipsometry, ethanol, nanosized film, index of refraction.
SIMULATION OF THE COALESCENCE PROCESS OF GOLD NANOPARTICLES BY MONTE-CARLO METHOD – 129 page.
A.Yu. Kolosov, N.Yu. Sdobnyakov, P.V. Komarov, D.N. Sokolov, T. Yu. Zykov, V.A. Hashin
Abstract: The simulation of the coalescence process of gold nanoparticles for different initial configuration by Monte-Carlo method was carried out. The interaction between nanoparticles was described by many-body Gupta potential. It was determined that in some cases the nanoparticles coalescence could happen under much lower temperatures than the temperature of crystal-liquid phase transition for the current size of nanoparticles. Moreover, the coalescence doesn’t happen at all at certain distances between nanoparticles of an initial configuration. The evolution of the neck formed at the coalescence of different-sized particles was investigated.
Keywords: gold nanoparticles, coalescence, Monte-Carlo method, Gupta potential, phase transition, neck.
THE SURFACE RELIEF ANALISIS OF Sm(Co, Cu)5 SINGLE CRYSTALS BY ATOMIC–FORCE MYCROSCOPY – 143 page.
Yu.V. Kuznetsova, E.L. Ayriyan, O.B. Dyogteva, N.P. Suponev
Abstract: The relief of Sm(Co,Cu)5 single crystal surfaces is investigated by AFM methods. The analysis of surface images of all samples is carried out by using the scanning probe microscope SOLVER P47 software.
Keywords: microstructure. scanning-probe microscopy, rare–earth intermetallic.
LIGHT ABSORPTION AND SCATTERING IN THE POLYMER COMPOSITE NANOMATERIALS BASED ON CADMIUM SULFIDE – 147 page.
D.M. Kul`batskiy, N.M. Ushakov
Abstract: The results of the experimental investigations and calculations of the coefficient of collimated optical absorption and scattering coefficients by the «adding-doubling» method in the polymer composite nanomaterials based on cadmium sulfide are represented. Detected peak scattering at 590-950 nm depending on the size of the nanoparticles is discovered.
Keywords: nanocomposite, nanoparticle, optic properties, scatter coefficient.
THE EFFECT OF MAGNETIC PRESSURE ON THE SURFACE TENSION FOR METALS IN THE SOLID STATE – 154 page.
V.K. Kumikov
Abstract: The paper is devoted to the analysis of systematic errors, arising during the high-temperature measurements of surface tension for metals in the solid state by the compensation zero creep method. The source of the errors assisted with electric heating is the pinch effect in the sample, which substantially effects on the measuring value and should be taken into consideration by the special correction.
Keywords: surface tension, zero creep, magnetic pressure, pinch effect.
THE DEVICE FOR THE MEASUREMENTS OF SURFACE TENSION FOR METALS IN THE SOLID STATE – 159 page.
V.K. Kumikov
Abstract: The shortcomings of compensation zero creep method for the measurements of surface tension for metals σ in the solid state and obstacles of high-temperature measurements in vacuum are analyzed in present paper. The device for σ measurement, in which the shortcomings of traditional methods were eliminated, is suggested.
Keywords: surface tension, zero creep.
SORPTION OF COPPER IONS FROM THE WATER SOLUTION BY PARTICLES OF NANOSIZED MAGNETITE – 165 page.
O.D. Linnikov, I.V. Rodina, A.P. Tjutjunnik, V.G. Shevchenko, А.Е. Yermakov, I.V. Medvedeva, А.А. Mysik, M. А. Uimin, Platonv V.V., Osipov V.V.
Abstract: Sorption of copper ions from water solution by nanosized magnetite performed by three different methods was studied. It was shown that magnetite is effective sorbent for removing copper ions from polluted natural waters and sewage. The obtained data testify that the process of sorption of copper ions by magnetite has chemisorptions character.
Keywords: magnetite, ions of copper, sorption, nanoparticles, chemisorptions.
SIZE DEPENDENCIES FOR THE SURFACE CHARACTERISTICS OF NANO-DIAMOND WITH THE VARIATION OF ISOTOPE COMPOSITION – 172 page.
M.N. Magomedov
Abstract: In this paper we present calculated isothermal-isomorphic dependencies of specific surface energy (σ), its isochoric derivative respecting to the temperature (σ’), and surface pressure (Psf) versus size of nano-diamond of 12C and 13C at 100K and 4300K. It is shown that ratio σ(12C)/ σ(13C) decreases at reduction of the size along both isotherms, but σ’(12C)/ σ’(13C) – increases at reduction of the size as appreciably, as temperature is lower. The ratio (13C) increases with reduction of the size as appreciably, as temperature is higher.
Keywords: diamond, isotopes, nanocrystal, Debye temperature, Gruneisen parameter, surface energy, surface pressure, size compression.
INVASTIGATION INTO NANOSTRUCTURED FUNCTIONAL COATINGS FOR DIFFERENT APPLICATIONS BY USING OPERATIVE METHODS OF CONTROLE – 181 page.
A.K. Mazeeva, A.A. Ramaldanova, N.V. Yakovleva, T.I. Bobkova, E.Yu. Geraschenkova, B.V. Farmakovsky
Abstract: This paper describes methods, used in FSUE “CRISM “Prometey”, such as scanning electron microscopy, X-ray diffractometry, scanning probe microscopy, optical microscopy, X-ray fluorescent elemental analysis and others for analysis of designed coatings structure.
Keywords: structure test, microscopy, X-ray diffractometry, X-ray fluorescent analysis, chemical composition, phase transformation, porosity, calorimetry, coating.
FORMATION OF NANOSTRUCTURES ON THE SURFACE OF BISMUTH SINGLE CRYSTALS IN THE ATOMIC HYDROGEN’S ATMOSPHERE – 189 page.
O.I. Markov, Yu.V. Hripunov
Abstract: The AFM-research of the surface morphology of a bismuth cleavage single crystal after exposure in the environment of atomic hydrogen was conducted. It was found that the surface topography changes due to nanoscale structures.
Keywords: atomic hydrogen, bismuth, self-organization.
MICROWAVE DIELECTRIC CONSTANT AND ATTENUATION IN POLYMER NANOCOMPOSITE MATERIALS BASED ON NANOPARTICLES OF IRON AND CADMIUM SULFIDE – 195 page.
S.Yu. Molchanov, N.M. Ushakov
Abstract: The results of the study of the complex dielectric constant and loss tangent at frequencies from 1GHz to 12GHz in the samples of polymer composite nanomaterials based on iron oxide and cadmium sulfide in the bulk stabilized polypropylene and on the surface of teflon, respectively are shown. The studies were conducted in an open atmosphere at room temperature.
Keywords: nanocomposite, nanoparticle, dielectric properties, microwave frequency.
RESEARCH OF CORROSION STABILITY OF THE NANOSTRUCTURAL NITINOL – 200 page.
E.O.Nasakina, M.A.Sevostyanov, A.S.Baikin, A.G.Kolmakov, V.T.Zabolotny
Abstract: During the work the structure and corrosion stability in buffer solutions of various acidity of the nanostructural nitinol after various processing was investigated. Concentration of metals in the
solution was measured by means of the atom-issue spectrometer with induction plasma. The greatest concentration of metals was observed in the most acid environment, slightly smaller in physiological solution. It is established that thermal processing reduces corrosion stability of the material.
Keywords: nitinol, nanostructure, corrosion stability, buffer solutions.
SYNTHESIS AND MAGNETIC PROPERTIES OF Y1-xSrxFeO3 NANOCRYSTALS (x = 0.0 AND 0.2) – 206 page.
Nguyen Anh Tien
Abstract: The YFeO3 and Y0,8Sr0,2FeO3 nanocrystals with an average particle size < 30 nm have been prepared by the co-precipitation method in aqueous solution of sodium carbonate containing theY3+, Sr2+ and Fe3+ ions. Magnetization and coercive force of the doped ferrite Y0,8Sr0,2FeO3 were higher than of the pure YFeO3, such characteristics could be a result of presence of Sr2+ ions increasing anisotropy of magnetic crystals.
Keywords: coprecipitation, YFeO3 and Y0,8Sr0,2FeO3 nanocrystals, coercivity, magnetization characteristic.
PALLADIUM NANOPARTICLES AS CATALYST OF ISOTOPE EXCHANGE MOLECULAR HYDROGEN REACTION – 212 page.
A.A Odintsov, M.O. Sergeev, O.A. Boeva
Abstract: It has been detected, that the size of metal nanoparticles has an influence on adsorption properties and catalytic activity of deposited palladium catalysts used in H2 – D2 exchange reactions and ortho-para protium conversion reactions. Nanoparticles have been obtained by the method of radiation-chemical reduction using reverse-micellas solutions. The structure and the size of prepared nanoparticles of palladium have been also studied.
Keywords: Nanoparticles, palladium, catalytic activity, catalysis, size effects, isotope exchange, reverse-micellas solution.
STRUCTURE AND MECHANICAL PROPERTIES OF CERAMIC COPRECIPITATE OF PENTOXIDE Nb2(1-y)Ta2yO5 – 219 page.
M.N. Palatnikov, O.B. Shcherbina, V.V. Efremov, A.A.Janichev, N.V. Sidorov*, V.V. Pasechnyi
Abstract: In this paper we studied the structure and mechanical properties of ceramics Nb2O5 and ceramics based on coprecipitated pentoxide Nb2(1-y)Ta2yO5, and the effect of treatment with concentrated light flows (CLF) on the structure and properties of these materials, using scanning probe microscopy and Raman spectroscopy (RS).
Keywords: concentrated light flows, the coprecipitate pentoxide, Raman spectra, micro-and nanostructures, micro-hardness, Young’s modulus, strength.
SYNTHESIS OF THE NANOCLUSTERS OF ZINC AND COPPER OXIDES FROM SOLUTIONS OF ORTHOPHOSPHATES ON LASER ABLATION OF POROUS SAMPLES – 230 page.
М.P. Patapovich, Trinh Ngoc Hoang, Le Thi Kim Anh, A.P. Zajogin
Abstract: Spectroscopic studies of the surface laser plasma formed close to the porous body containing nanoquantities of different zinc and copper salts subjected to the effect of double laser pulses were performed. The possibility to develop the methods for the production of metal oxide nanoclusters was demonstrated. The quantity and the composition of metal oxide clusters could be varied depending on the concentration of the starting metals in the solutions used.
Keywords: nanoclusters, pulsed laser sputtering, surface laser plasma, laser spark spectrometry, metal oxides, double laser pulses.
EQUATION OF STATE VAN DER WAALS AND ITS MODIFICATIONS IN MODEL FOR INTERACTING POINT CENTER – 235 page.
G. Petrik
Abstract: In this paper we show that the set of two- and three-parameter equations of state (EOS) of the van der Waals type, considered empirical modifications of van der Waals EOS, after reformulation can be regarded as physically grounded EOS belong to single families of the new equations obtained by the author on the basis of interacting point centers model. EOS different manifestation of forces of attraction and repulsion between the model objects reflected in the values of the control parameters of the model.
Keywords: model of the properties, point centers, equations of state of the van der Waals type, the control parameters, a family of equations of state, intermolecular interaction.
THE MOLECULAR DYNAMICS OF THERMOACTIVETED PROCESS FORMING OF INTERFACE STRUCTURE FOR 3D ME/C COMPOSITION LAYERED COMPOSITES – 248 page.
V.A. Polukhin, R.M. Belyakova, E.D. Kurbanova, A.Y. Galashev
In this article we presented the analysis of molecular dynamic simulations results. The specificities of thermoactivated structure phase changes in 3D Me/C interface forms with grapheme layers and 3D transition metal surface planes have been revealed. The relaxation transition of interface Me-C coordinations and the forming of two-dimensional ring clusters, as the sites of new superlattices have been observed. The correlation of short and long range ordering have been classified.
Keywords: molecular dynamic simulations, thermoactivation, interface, composite, structure phase changes, nanostructure.
THERMODYNAMIC APPROACH TO THE PROBLEM OF THE SIZE DEPENDENCE OF THE THIN FILM MELTING TEMPERATURE – 257 page.
V.M. Samsonov, A.G. Bembel, D.N. Sokolov, N.Yu. Sdobnyakov
Abtract: Size dependences of the melting temperature for supported thin films were calculated using relations obtained earlier. A conclusion is made that the most noticeable size effect should be expected when the film is characterized by the anomalous temperature dependence of the film substance density.
Keywords: size dependence, melting temperature, supported thin films.
DEPENDENCE OF EXCESS FREE ENERGY AND DISJOINING PRESSURE OF THE NECK FORM BETWEEN TWO SPHERICAL NANOPARTICLES – 264 page.
N.Yu. Sdobnyakov, A.Yu. Kolosov, D.N. Dokolov, A.S. Antonov, A.N. Bazulev
Abstract: On the basis of thermodynamic perturbation theory the calculations of the excess free energy and disjoining pressure for the liquid neck between two spherical nanoparticles have been carried out using different approximations for the neck form. In terms of disjoining pressure the liquid neck stability has been analyzed.
Keywords: neck, excess free energy, disjoining pressure.
SEGREGATION ENERGY AND SURFACE COMPOSITION OF THE Cu-Mn ALLOYS ACCORDING TO AUGER ELECTRON SPECTROSCOPY – 270 page.
I.N. Sergeev
Abstract: The composition of topmost atomic layers of single crystal solid solution (100)Cu-4 at. % Mn was studied in the range of T = 300..875K by AES. Data on the surface composition are compared with the results for polycrystal Cu-22,5 at. % Mn, obtained in previous work. It is shown that in the nonequilibrium region segregation is determined by the diffusion length of Mn in Cu. For equilibrium state are defined the segregation energy and other thermodynamic parameters of the surface.
Keywords: Cu-Mn alloys, Auger electron spectroscopy, surface segregation, segregation energy, diffusion length.
THE ENERGY CONSERVATION LAW IN QUANTUM DISTURBANCE THEORY – 277 page.
L. Skopich
Abstract: It is demonstrated, that usual application of certain formulas in limits of the first approximation of the quantum perturbation theory is unsubstantial. Besides, it has been refused current opinion about the energy conservation law’s violation for little interval of time between initial and final states considered system.
Keywords: energy conservation law, quantum mechanics, perturbation theory.
THE STUDDING OF INFLUENCE OF GAS CONCENTRATION IN A VACUUN CHAMBER ON MICROSTRUCTURE AND PHISICO-MECHANICAL PROPERTIES OF FILMS BASED ON THE Ti-Al-N – 281 page.
T.O. Soshina
Abstract: The effect of nitrogen (N2) in the gas mixture on the phase composition, surface morphology, structural characteristics and physico-mechanical properties of films based on Ti – Al – N, formed by pulsed magnetron sputtering has been investigated. Polycrystalline film with a unique set of physical and mechanical properties have been obtained at the optimum of nitrogen (N2) concentration in the gas mixture.
Keywords: magnetron sputtering, concentration of nitrogen in the gas mixture, phase structure, a microstructure, physico-mechanical properties.
PROPERTIES OF COMPOSITES BASED ON IRON OXIDE NANOPARTICLES IN LOW DENSITY POLYETHYLENE MATRIX – 290 page.
A.N. Ul’zutuev, N.M. Ushakov
Abstract: The results of studies of the dielectric and optical properties of composites based on iron oxides nanoparticles are received. The studies were performed in the temperature range 30-100°C at frequencies of kHz and MHz, and at wavelengths of 600 – 1000 nm.
Keywords: nanocomposite, nanoparticle, dielectric properties, optical properties.
THE FORMATION OF TiO NANOCLUSTERS IN THE SURFACE LASER PLASMA WHEN TITANIUM AND BARIUM TITANATE ARE SUBJECTED TO THE EFFECT OF DOUBLE LASER PULSES – 296 page.
Fadaeian Ahmad Reza, S.V. Protsenko, А.P. Zajogin
Abstract: The effect of an additional laser pulse on the formation of the composition and charge state of the surface laser plasma was studied by the laser spark spectrometry (LSS) method. It was shown that there is a possibility for an increase in the portion of titanium ions during ablation of the titanium alloy surface and barium titanate ceramics by double laser pulses as well as of clusters under the effect of a series of double laser pulses on the target.
Keywords: radicals, pulse laser sputtering, surface laser plasma, laser spark spectrometry, multicharged ions, double laser pulses.
MODELING A FORMATION OF NANOSTRUCTURES ON POLYPYRROLE -302 page.
M.M. Falchary, N.K. Plugotarenko
Abstract. In this paper we carry out simulation of electrically conductive polymer nanostructured materials by the example of polypyrrole. Implementation of modeling was performed by the Wang-Landau and entropic Monte Carlo simulation based on a model with a fixed valence angle. For modeling polymerization process we used an algorithm based on the principles of irreversible aggregation of Eden.
Keywords: nanostructure, Hartree-Fock energy, gas sensitive materials, mathematical modeling, Monte Carlo, quantum-chemical calculations.
MODEL FORMING NANOSTRUCTURE IN HIGH-CARBON WIRE IN THE PROCESS OF RADIAL-DISPLACEMENT BROACH – 309 page.
V.A. Kharitonov, M.Yu. Usanov
Abstract: In this work we showed that techniques such as drawing and broaching in roller don’t let intensively to grind grain. Effective way of grind grain is radial-displacement broach. This paper also contains the results of modeling radial-displacement broach.
Keywords: wire, nanostructure, monotony, deformation, drawing, broaching, radial-displacement broach, accumulated deformation.
SYNTHESIS OF CALCIUM AND ALUMINUM OXIDES FROM SOLUTION OF PHOSPHATES ON LASER ABLATION OF POROUS SAMPLES – 314 page
Trinh Ngoc Hoang, M.P. Patapovich, Le Thi Kim Anh, Pham Uyen Thi, A.P. Zajogin
Abstract: The spectroscopic investigations of the surface laser plasma formed close to the porous body containing nanoquantities of different calcium and aluminum salts under the effect of two successive laser pulses were performed. The possibility for the development of methods to obtain the nanoclusters of metal oxides was demonstrated. Depending on the concentration of the starting metals in the solutions used, one can vary both the quantity and composition of the metal oxide clusters.
Keywords: pulsed laser sputtering, surface laser plasma, laser spark spectrometry, metal oxides, double laser pulses.
THE INTERFACE ENERGY OF SMALL METAL PARTICLE ON THE BOUNDARY WITH SELF-MELTING – 319 page.
I.G. Shebzukhova, L.P. Arefjeva, Kh. Khokonov
Abstract: The electron-statistical method is used to determine the dimensional dependences of the interfacial energy of the rhodium small particles on the boundary with self-melting. Interface energy was calculated for spherical and cubic particles. The oscillation and dispersion corrections were taken into account. The formulas for polarization correction and temperature contribution were modified.
Keywords: small particles, dimensional dependences, interface energy.
OBTAINING NANODIAPERSE OXIDE ELECTROLYTS WITH IONIC CONDUCTIVITY USING POLYHYDRIC ALCOHOLS IN SHS METHOD – 326 page.
S.N. Shkerin, O. I. Gyrdasova, A.V. Nikonov, V. N. Krasil’nikov
Abstract: By method of self-evaluation high-temperature synthesis (SHS) single phase superfine powder was obtained: CeO2, doped transition elements, solid electrolytes La0,88Sr0,12Ga0,82Mg0,18O2,85 and La0,5Sr0,5Ga0,05Mg0,95O2,85. As a combustible, ethylene glycol, glycerol, and their mixtures in various proportions were used.
Keywords: solid electrolytes, the conductivity, nanomaterials, self-evaluation high-temperature synthesis.
EFFECT OF NANOSTRUCTURE ON PARAMETERS AND CONFIGURATION OF Sm-Zr-Co-Cu-Fe ALLOYS MAGNETIC DOMAINS – 333 page.
M.B. Lyahova, E.M. Semenova, N.P. Suponev, R.P. Ivanov, E.L. Ayriyan
Abstract: The results are presented of the magnetic domain structure research in nanostructured heterogeneous rare-earth intermetallide of the Sm-Zr-Co-Cu-Fe type. The domain structure was investigated using optical and magnetic force microscopy. A Comparative analysis was carried out of nano- and domain structure parameters. It has been shown that the nanosized cell structure, being formed in these materials as a result of the thermal treatments, yields a transformation of magnetic domains. Parameters of the domains in questions in basic structure of alloys were determined.
Keywords: magnetic domain structure, nanostructure, magnetically hard alloys.
CALCULATION OF NUCLEATION ON CRYSTALLIZATION OF MELTS COOLING CURVE – 5 page.
V.D. Aleksandrov, V.V. Dremov, V.A. Postnikov, N.V. Shchebetovskaya
Annotation: The method of calculation of parameters of nucleation and mass crystallization of melts (the degree of crystallinity, the heat coagulation of the germ, the critical size of crystal germ and others) on cooling curves.
Keywords: crystallization, nucleation, cooling curves, the parameters of nucleation.
ON RESOLUTION OF ELECTRON IMAGES OF DEVISED DEVICES COVERED WITH NANOTECHNOLOGICAL FILMS – 13 page.
E.A. Acheeva, V.N. Grinyuk, V.A. Sozaev
Annotation: The possibility for optical resolution of electron-optic transformers by means of selection of initial energy of electrons within the film of thicknesses 46÷282 nm has been shown.
Keywords: nanotech films, electron-optical converter, the blur parameter of the electron energy.
STANDARD ENTHALPIES OF FORMATION OF CLUSTERS IN Pb-Bi SYSTEM IN VAPOUR AND CONDENSED PHASES – 16 page.
N.M. Barbin, D.I. Terentev, S.G. Alekseev
Anotation: The standard enthalpies of formation of clusters in condensed phase of Pb-Bi system were calculated by Miedema method. Also, the standard enthalpies of formation of clusters in vapour phase of Pb-Bi system were calculated.
Key words: intermetallic compound, clusters, Pb-Bi system, standard enthalpy of formation.
THE INFLUENCE OF THERMOSTIMULATED SEGREGATION ON PLASMON RESONANCE AND VALENCE ELECTRON DENSITY IN SURFACE LAYER FOR THE Cu–Mn ALLOY – 20 page.
K.Ch. Bzhihatlov, I.N. Sergeev
Annotation: The influence of thermostimulated segregation on surface electrons properties of polycrystalline Cu-22,5 at. % Mn alloy was investigated by REELS and AES means. Dependences of valence electrons density on temperature, structure and depth of surface layer are calculated by plasmon energy (Eb), extracted from loss spectra. Estimation of local physical properties of a surface is discussed using Eb.
Keywords: reflection electron energy loss spectroscopy, Auger electron spectroscopy, plasmon, valence electron density, Cu-Mn alloys.
QUANTUM-CHEMICAL MODELING BI CLUSTERS -27 page.
E.N. Gribanov, O.I. Markov, Yu.V. Khripunov
Annotation: In this paper results of calculations by quantum-chemical methods of structure and power parameters of nanoclusters of bismuth Bi8, Bi18, Bi50, Bi98, Bi162 are presented.
Keywords: cluster, bismuth, semiconductor – semimetal transition.
FORMATION OF NANO SIZE CLUSTERS IN ALLOYS DURING THE PROCESS OF FORMATION OF SUBMICROCRYSTALLINE STRUCTURE AT INTENSIVE PLASTIC DEFORMATION – 33 page.
A.I. Deryagin, V.A. Zavalishin, V.V. Sagaradze, V.А. Ivchenko, B.M. Efros
Annotation: It was found out the process of nuclear stratification of alloys Fe58Ni30Cr12 (mac.%) under the influence of strong plastic deformation at room temperature. Intensity of increase of Ni concentration (and respective pauperization of Fe) in clusters with size more than ~1,5 nm is ~2,5% per unit of logarithmic deformation, the share of clusters with the structure which is distinct of a matrix more than 5% is up to 10% of value under the strong deformation.
Keywords: cluster, dot defects, superparamagnetism, specific magnetization, intensive deformation.
THE THERMODYNAMIC ANALYSIS OF CONDITIONS OF DISSIPATIVE PHASES OCCURRENCE AT INTERACTION OF INTERMETALLIC COMPOUNDS MICROCRYSTALS – 39 page.
V.V. Zhigunov, A.A. Alehina
Annotation: Conditions of occurrence during diffusion interaction between intermetallic compounds the phases which are absent on the phase equilibrium diagram of binary system is received by methods of nonequilibrium nonlinear thermodynamics.
Keywords: Nonequilibrium nonlinear thermodynamics, dissipative phases, diffusion interactions, microcrystals, intermetallic compound.
THE MATHEMATICAL DESCRIPTION OF PROCESS OF PHASES FORMATIONS DURING OBTAINING MICRO- AND NANOCRYSTALS – 47 page.
V.V. Zhigunov, A.I. Lavit
Annotation: A variant of shock-capturing method for Stefan problem solution involving emerges with modeling of diffusion in multiphase solid body is proposed. Generalized Galerkin method is used because its coordinate functions not obliged to satisfy natural boundary conditions. Time integration is executed with Crank-Nicholson finite-difference scheme. Space integration is executed with finite element method.
Keywords: Diffusion, multiphase binary system, microcrystals, intermetallic compound, mathematical modelling.
INVESTIGATION OF THE FORMATION PROCESSES OF ULTRADISPERSE URANIUM OXIDES FROM NITRATE COMPOUNDS OF URANYL UNDER THE EFFECT OF DOUBLE LASER PULSES – 51 page.
A.P. Zajogin, D.S. Umreiko, A.I. Komyk, A.A. Zajogn
Annotation: During the spectroscopic investigation of the laser plasma formed close to the surface of a porous body, containing microquantities of uranyl nitrate with organic ligands, subjected to the effect of high-power sequential laser pulses the possibility to form the specific ion, atom, and molecular composition of the plasma and the particular forms of uranium oxides in it using the organic ligands with different methyl groups was demonstrated.
Keywords: ultradisperse uranium oxides, uranyl nitrates, organic ligands, porous bodies, double laser pulses.
MECHANISM, KINETICS OF FORMATION AND GROWING NONLINEAR CRYSTALS FOR OPTOELECTRONICS – 57 page.
B.I. Kidyarov
Annotation: The goal of this paper is the further development of theory and methods of kinetics and mechanisms of the crystal nucleation and growth as well as a systematic experimental research of the crystal genesis. We also aimed on a systematic analysis of the available data on the relationship of structural properties of crystals and liquid phases with the processes of the formation and growth. On the basis of this analysis, general methods of design and growth of perfect inorganic crystals may be proposed including production of some known and new acentric crystals for fundamental and allied physics.
Keywords: nonlinear optical crystals (NLO crystals), crystals of centrosymmetric (CS crystals), crystals of noncentrosymmetric (NCS crystals), crystal nucleation, crystal growth.
THE INVESTIGATION OF NANOSIZED SILICON DIOXIDE FILM STRUCTURES BY ELLIPSOMETRIC METHOD – 87 page.
D.A. Kim, N.Yu. Sdobnyakov, D.N. Sokolov, E.A. Voronova, O.V. Mikhailova, T.Yu. Zykov
Annotation: On the basis of analyzing the spectrum of the ellipsometric angles Δ и ψ the definition of thickness layer SiO2 on the different substrates using the photometric spectral ellipsometer has been held.
Keywords: ellipsometry, silicon dioxide, nano-sized film, the film thickness, 3D-profile of the films.
SELF-ASSEMBLY OF NANOWIRES: COMPUTER SIMULATION OF DNA MACROMOLECULES – 96 page.
P.V. Komarov, P.S. Kutilin, L.V. Zherenkova, N.Yu. Sdobnyakov, D.N. Sokolov
Annotation: The Monte Carlo method is employed to study the conditions of self-assembly of nanowires in the matrix of DNA in aqueous solution by Monte Carlo method. The metal coating is formed as a result of electrostatic interaction of negatively charged groups of the matrix molecule and positively charged functionalized gold nanoparticles. The model parameters are estimated at which continuous metal coatings are formed via self-assembly.
Keywords: potential Gupta, Monte Carlo, the self-assembly of nanowires, DNA.
MEСHANOСHEMICAL SPECIFICITY OF METALS POLISHING WITH TRIBOCHEMICAL ACTIVE ABRASIVE MATERIALS – 106 page.
L.F. Koroleva, S.V. Smirnova
Annotation: Meсhanoсhemical concept is proposed as a tribochemical process of metals polishing consisting of two stages: the first oxides films formation on metal surface by friction, the second stage of activation is linked to the destruction and removal of film. It is shown that the process of defining the quality of polishing metals, it is the process of formation of oxide film on the surface and its remove.
Keywords: мechanochemical finish polishing, oxides solid solutions, deformation, oxides film, kinetics, surface roughness.
THE INFLUENCE OF NANOSTRUCTURE ON THE MAGNETIZATION REVERSAL PROCESSES IN HETEROGENEOUS R‑Zr‑Co‑Cu‑Fe ALLOYS – 114 page.
M.B. Lyakhova, E.M. Semenova, N.P. Suponev, R.P. Ivanov
Annotation: Investigation of nanostructure by the methods of AFM of heterogeneous alloy (Sm0,5 Gd0,5) 0,85 Zr0,15(Co0,690Cu0,088Fe0,222) 6,0 after different heat treatment processes are present in this paper. It is shown that “cell” structure forms in the two main structural components of the alloy during heat treatment processes. This type of structure provides high coercive state in this type of alloys.
Keywords: high coercive state, nanostructure, heterogeneous hard magnetic alloy, atomic force microscopy.
ON THE CHANGE OF THE SURFACE ENERGY UNDER THE ALL-ROUND COMPRESSION OR SPRAINING OF THE CRYSTAL – 120 page.
M.N. Magomedov
Annotation: Expressions for the dependencies of the specific surface energy σ and its isochoric derivative with respect to the temperature (∂σ/∂T)V versus of the relative volume V/V0 of the simple matter crystal are received. It is shown that isotherm σ (V/V0) has a maximum at (V/V0)max<1 , it decreases at compression or spraining, and it is passing at the definite value (V/V0)frS<(V/V0)max<1 and (V/V0)frL>1 to negative region: σ (V/V0) fr=0 . It must cause the fragmentation of the crystal at V/V0<(V/V0)frS or V/V0<(V/V0)frL.
Keywords: surface energy, Debye temperature, Gruneisen parameter, compression, spraining, neon, iron, fragmentation, Earth’s core.
THE APPLICATION OF CELLULAR AUTOMATION MACHINE SOFTCAM FOR THE MODELING OF Si NANOCRYSTALS FORMATION IN A SiOx MATRIX – 129 page.
I.V. Matyushkin, S.V. Korobov
Annotation: The mathematical model is developed and realized by means of cellular automation machine SoftCAM. At the adopted parameterization the simulation results are consistent with the experimental data satisfactorily.
Keywords : cellular automata, self-organization, silicon nanocrystals.
SEDIMENTATION OF NANOPOWDER OF MAGNETITE IN WATER SOLUTION IN A GRADIENT MAGNETIC FIELD -134 page.
I.V. Medvedeva, O.D. Linnikov, M.A. Uimin, A.Ye. Yermakov, A.A. Mysik, I.V. Bysov, T.A. Nabokova, S.V. Zhakov, V.G. Gaviko, N.N. Shchegoleva, V.A. Tsurin, I.V. Rodina, V.V. Platonov, V.V. Osipov, A.V. Han’kova
Annotation: Sedimentation of nanopowders of magnetite in a water solution at presence and absence of a gradient magnetic field accelerating sedimentation is studied on special laboratory setup. It is shown that in water solution there is a formation of aggregates of the micron sizes from nanoparticles of magnetite. A major factor leading to aggregation of nanoparticles of magnetite in micron clusters is the magnetic attraction between particles.
Keywords: Sedimentation, magnetite, aggregation, nanoparticles, magnetic field
RESEARCH OF MONOMETALLIC AND BINARY FCC-CLUSTERS WITH THE SYMMETRY AXIS OF THE FIFTH ORDER – 143 page.
V.S. Myasnichenko, M. D. Starostenkov
Annotation: The formation of atomistic structures of Cu, Au, Ag Cu-Au clusters was studied in the computer molecular dynamics experiment. The simulation of the crystallization process of clusters with the number of atoms from 300 to 1092 is executed. The structure of cluster searched by the method of common neighbors analysis. The decahedron-shaped structure of bimetallic Cu-Au cluster with seven completed icosahedral cores was obtained. The principles of the construction of bimetallic clusters with several icosahedral cores were offered.
Keywords: nanocluster, axe, icosahedron, fractal.
STUDY OF SYNTHESIS OF LaFeO3 NANOCRYSTALS -150 page.
Nguyen Anh Tien, Nguyen Tuan Khanh, Tran Thi Thuy Dung
Annotation: Nanocrystalline LaFeO3 is prepared by sol-gel method using citric acid and oleic acid as surface-active substances. The results demonstrate that after sintering at 850°C in 3 hours, we obtain LaFeO3 nanocrystals, sized < 50 nm, independent on which acid was used. The present of citric acid not only reduces the average particle size of powders LaFeO3, but also increases their surface area in comparison with oleic acid.
Keywords: sol – gel method, LaFeO3 nanocrystals, oleic acid, citric acid, surface-active substances, surface area of powders.
PHYSICAL AND CHEMICAL METHODS FOR STUDYING POLYOXOMENALATS NANOCLUSTER AND COMPOSITIONS ON THEIR BASIS – 156 page.
A.A. Ostroushko, M.O. Tonkushina, V.Yu. Korotaev, A.P. Safronov, K.V. Grgegorshevskii, N.A. Martynova, I.B. Kutyashev
Annotation: Experience of complex attestation and studying of physical and chemical properties of nanocluster polyoxometalats and polymer-containing compositions on their basis with use of some independent methods is generalized. Identification possibility of produced compounds from the point of view of their structure, a crystallography and definition of transport parameters, photochemical and other properties is shown.
Keywords: Polyoxomolybdates, nanocluster, polymer-containing compositions, physical and chemical methods of studying and the characteristic.
THERMODYNAMIC THEORY OF MELTING IN SMALLEST PARTICLES – 163 page.
V.A. Pavlov
Annotation: Depression of melting temperature at diminution of particle diameter was first observed a hundred years ago. In this article there are offered formulae describing this effect satisfactorily when the number of atoms in an argon particle is over a dozen.
Keywords: nanothermodynamics, differential chemical potential, integral chemical potential, surface tension.
EFFECTS OF CONCENTRATED LIGHT FLOWS ON MECHANICAL PROPERTIES AND STRUCTURE OF CERAMIC PENTAOXIDE NIOBIUM – 167 page.
M.N. Palatnikov, O.B. Shcherbina, V.V. Efremov, N.V. Sidorov
Abstract: Investigating the effect of concentrated light beams on the structure and mechanical properties of ceramic Nb2O5. Under the influence of high-energy light in Nb2O5 ceramics produced micro-and nanostructure of fractal type and is caused in part “island” structure of the crystal lattice. Ceramic Nb2O5, exposed high-energy light radiation has improved mechanical properties (microhardness, strength, fracture toughness, fragile micro strength).
Keywords: concentrated light beams, the Raman spectroscopy, micro-and nanostructures, micro-hardness, Young’s modulus, strength, fracture, fragile micro strength.
SYNTHESIS OF CALCIUM OXIDE NANOCLUSTERS FROM THE SALTS INTRODUCED INTO PORIOUS BODIES ON LASER – CHEMICAL ACTIVATION OF THE PROCESSES -176 page.
M.H. Patapovich, H. N. Trinh, J.I. Buloichik, A.P. Zajogin
Annotation: The formation dynamics of calcium ions was studied under the effect of double laser pulses on the surface and bulk of porous bodies with solutions of Ca salts (CaCl2, Ca(NO3)2, CaCo3, and Ca3(PO4)2 ) in the air at the laser pulse energies 50-60 mJ and interpulse times 0-12 μs. It was found that the intensities of Ca II line (λ=393.367 nm) for the indicated salts form the following series: phosphate> carbonate>nitrate≥chloride.
Keywords: synthesis of CaO nanoclusters, formation dynamics, double laser pulses, laser-chemical process activation.
ABOUT TWO СONTROLLING PARAMETERS OF INTERACTING POINT CENTERS MODEL AND THEIR MEANING – 181 page.
G.G. Petrik
Annotation: We continue to study the thermal equation of state derived by the author based on the model of interacting point centers. The relationship between the two control parameters of the model: the previously found parameter χ thermodynamic level and a new parameter θ of the molecular level are identified and discussed. Both parameters are determined by the ratio of the intermolecular interaction forces – attraction and repulsion.
Keywords: the models, interacting point centers, the equation of state, the control parameters, one-parameter family of equations of state, intermolecular interaction.
QUANTUM-CHEMICAL STUDY OF ACTIVE SITES OF GOLD NANOCLUSTERS – 188 page.
D.A. Pichugina, D.F. Mukhamedzyanova, S.N. Lanin
Annotation: The results of systematic quantum-chemical study of different hydrocarbons adsorption and activation on gold clusters, and the investigation of the nature of active sites including the influence of cluster’s structure and charge on its chemical properties are presented. It is shown that Auδ+ sites availability increases binding energy in СxHy–Aun and reduces the activation energy in allylic isomerization of allylbenzene catalyzed by Aun.
Keywords: Gold clusters, density functional theory, catalysis, adsorption, hydrocarbons, allylbenzene, isomerization.
PHYSICAL AND CHEMICAL FEATURES OF ELECTROEXPLOSIVE SPRAING OF Mo-C-Cu ELECTRICAL EROSION STABLE COATINGS – 194 page.
D.A. Romanov, E.A. Budovskikh, O.V. Olesyuk, V.E. Gromov
Annotation: By the method of electroexplosive spraying of structurally-free copper, molybdenum and graphite are formed on the surface of the copper contacts. Microcrystalline composite coatings contain matrix of pseudoalloys Mo-Cu with synthesized electrical erosion stability carbides MoC and Mo2C. Topography, structure and phase composition of coatings are studied. It is shown that with the increase of thermomechanical effect on the irradiated surface the carbide content in the coating increases.
Keywords: electrical explosion¸ spraying, composite coating, synthesis phase, carbides, psevdoalloy, phase composition, microstructure.
THE THERMODINAMIC APPROACH TO THE RIDDLE OF THE HEAT CAPACITY OF NANOSTRUCTURED MATERIALS – 200 page.
V.M. Samsonov
Annotation: The heat capacity of nanoclusters was treated using thermodynamics of surfaces, taking into account the surface enthalpy introduced by E. Guggenhein. It is shown that the cluster heat capacity should be greater then the capacity С p (b) of the corresponding bulk phase. However, the Cp/С p (b) ratio should not exceed 25-30% up to very small clusters containing 100 atoms. So, experimental data on metallic nanoclusters and nanostructures demonstrating that Cp exceeds Сp (b) in 2-5 times are incorrect.
Keywords: nanostructured materials, heat capacity, thermodynamics of the surface.
THE MEASUREMENT OF THE CURRENT-VOLTAGE CHARACTERISTICS OF A TUNNEL JUNCTION OF THE TUNGSTEN-GOLD – 206 page.
N.Yu. Sdobnyakov, A.S. Antonov, T.Yu. Zykov, D.N. Sokolov, E.A. Voronova, O.V. Mikhailova
Annotation: In this paper, we have been measured the current-voltage characteristics (CVC) of a tunnel junction of the tungsten-gold by scanning tunneling microscope (STM) «Umka-02-G». In addition, the factors were described of the tunnel system which may influence to the form of CVC on the example of a model system of tungsten-gold on the physical processes occurring in the probe tip voltage increases and could lead to a change in the length of the probe in particular.
Keywords: scanning tunneling microscope, the current-voltage characteristic, a tunnel junction of the tungsten-gold, thermal expansion of the probe.
STRUCTURE DYNAMICS OF SILVER CLUSTERS – 217 page.
U.G. Snyga, А.V. Beletskaya, D.А. Pichugina, N.Е. Kuz’menko
Annotation: Here we present the results of small silver clusters Agn (n=2-10) structures obtained by density functional theory using of Dirac-Coulomb-Breit Hamiltonian; the data of calculation and study of cluster’s structure parameters such as average interatomic distances, coordinational number, ansphericity, and form are also discussed. Sharp change of parameters is obtained for Ag7 which is the fist smaller volume cluster.
Keywords: silver clusters, density functional theory, structure, isomers, interatomic distances, coordinational number, cluster’s form.
PHYSICAL AND CHEMICAL PROPERTIES OF NANOPOWDERS Al2O3-Al (Cu) RECEIVED PULSED ELECTRONIC EVAPORATION – 222 page.
S.Yu. Sokovnin, V.G. Il`ves
Annotation: By means of evaporation by a pulse electronic beam in gas of low pressure and condensation on a cold crystallizer are received nanopowders alumina and Al2O3–Al(Cu). The specific surface area of powders reaches 338 m2/g. XRD analysis formation in powders an alpha, scale and тета phases alumina, and also amorphous components is established. Phase transformations into powders to temperature 1400 C are studied.
Keywords: alumina, nanopowders, an electron beam, phase transformations.
THE CALCULATION OF THE SIZE DEPENDENCIES OF THE HEAT OF FUSION FOR METAL NANOPARTICLES – 229 page.
D.N. Sokolov, N.Yu.Sdobnyakov, P.V. Komarov
Annotation: On the basis of temperature dependencies of internal energy the size dependences of heat of fusion for gold, cuprum, aluminum and cobalt nanoclusters have been calculated. For the simulation the Monte-Carlo method has been used and interaction between atoms have been described by many-body Gupta potential.
Keywords: heat of fusion, phase transition, skin-layer, metal nanoparticles.
COMPUTER MODELLING OF ORDERING OF STRUCTURAL UNITS AND CLUSTERS IN LITHIUM NIOBATE CRYSTALS -239 page.
O.R. Starodub, V.M. Voskresensky, N.V. Sidorov, M.N. Palatnikov, V.T. Kalinnikov
Annotation: Modeling of the processes occurring at formation energetically equilibrium oxygen-octahedral clusters in the ferroelectric phase of stoichiometrical of lithium niobate crystal (LiNbO3) is executed at qualitative level. It is shown that on energy it appears the most favourable cluster with parity Li/Nb = 0,98 that corresponds to experimental data of crystals grown with К2О.
Keywords: lithium niobate, modeling, clusters, vacancy models.
A STUDY OF MICROEMULSION BY ACOUSTIC SPECTROSCOPY METHOD -246 page.
T.V. Tikhonova, K.I. Kienskaya, G.V. Avramenko
Annotation: It have been studied the ultrasound velocity and attenuation at the range of frequency 0,5-20 MHz in oil/surfactant/water systems. Coexistence of domains have been found of the microemulsions based on nonionic surfactants.
Keywords: microemulsions, phase transition, coexistence domain, ultrasound spectroscopy.
NANOMODIFICATION OF β-AGI CRYSTALS – 252 page.
V.V. Tomaev, Y.S. Tver’yanovich, M.D. Bal’makov
Annotation: Nanostructured powder β-AgI was synthesized by using the exchange reaction in aquatic solutions of AgNO3 and KI. The size of the crystals was determined by electron microscopy scanning. It was shown that the powder b-AgI, modified in a ball vibratory mill VIBRATOR GM-945B, was composed of small γ-AgI (30 ÷ 70 nm) and large β -AgI (500 ÷ 1000 nm) nanocrystals. The most of the small crystals were located on the surface of larger ones.
Keywords: nanomodification, silver halides, silver iodide, mechanochemical treatment, the nanoparticles, the ionic conductivity.
SPECTRAL CONTROL OF THE FORMATION PROCESSES OF ALUMINUM NITRIDE CLUSTERS IN THE PLASMA WHEN ALUMINUM IS SUBJECTED TO SERIES OF DOUBLE LASER PULSES – 259 page.
Trinh, A.R. Fadeian, A.P. Zajogin
Annotation: The effect of an additional laser pulse on the formation of the specific component and charge composition of the surface laser plasma was studied by the method of laser spark spectrometry (LSS). The possibility to increase both the fraction of aluminum ions with different charging in the surface laser plasma in the mode of aluminum alloy (AD1) ablation by double laser pulses and AlN cluster under the effect of a series of double laser pulses on the target was demonstrated.
Keywords: AlN radicals, surface laser plasma, laser spark spectrometry, double laser pulses.