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Bulat L.P.,Saint Petersburg State University | Bublik V.T.,Moscow Institute of Steel And Alloys | Drabkin I.A.,GIREDMET Ltd. | Karataev V.V.,GIREDMET Ltd. | And 5 more authors.
Journal of Electronic Materials | Year: 2010

Bulk nanostructured polycrystals are prospective thermoelectrics. Fabrication and examination of nanostructured polycrystalline p-Bi-Sb-Te are discussed. The influence of fabrication conditions and the composition of the material on sizes of nanograins was investigated experimentally. Basic physical properties of fabricated nanothermoelectrics including nanocomposites were also studied. Theoretical estimation of the influence of phonon scattering on nanograin boundaries in bulk nanostructured thermoelectrics is presented. © 2010 TMS.


Bulat L.P.,Saint Petersburg State University of Information Technologies, Mechanics and Optics | Drabkin I.A.,GIREDMET Ltd. | Karatayev V.V.,GIREDMET Ltd. | Osvenskii V.B.,GIREDMET Ltd. | And 8 more authors.
Journal of Electronic Materials | Year: 2013

Ball milling with subsequent spark plasma sintering (SPS) was used to fabricate bulk nanothermoelectrics based on Bi x Sb2-x Te3. The SPS technique enables reduced size of grains in comparison with the hot-pressing method. The electrical and thermal conductivities, Seebeck coefficient, and thermoelectric figure of merit as functions of temperature and alloy composition were measured for different sintering temperatures. The greatest value of the figure of merit ZT = 1.25 was reached at the temperature of 90°C to 100°C in Bi0.4Sb1.6Te3 for sintering temperature of 450°C to 500°C. The volume and quantitative distributions of size of coherent dispersion areas (CDA) were calculated for different sintering temperatures. The phonon thermal conductivity of nanostructured Bi x Sb2-x Te3 was investigated theoretically taking into account phonon scattering on grain boundaries and nanoprecipitates. © 2013 TMS.


Syromotina D.S.,Tomsk Polytechnic University | Surmeneva M.A.,Tomsk Polytechnic University | Gorodzha S.N.,Tomsk Polytechnic University | Pichugin V.F.,Tomsk Polytechnic University | And 7 more authors.
Russian Physics Journal | Year: 2014

Results are presented of studies of the physical-mechanical properties of silver-doped calcium phosphate coatings formed by radio-frequency magnetron sputtering on a surface of technically pure VT1-0 titanium and 12Cr18Ni10Ti stainless chromium-nickel surgical steel. The films have the nanocrystalline structure of hydroxyapatite with mean diameter of the coherently diffracting domains equal to 20-30 nm. It has been established that the configuration of the magnetic field of the magnetron has an effect on the roughness, thickness, and refractive index of the coatings. The thickness of the coatings and the refractive index vary within the ranges 300-700 nm and 1.68-1.80, respectively. The nanohardness of the coatings is within the range 4-7GPa, the modulus of elasticity of the coatings depends on the material of the substrate and is equal to 130-150 GPa for titanium and 170-200 GPa for steel. Sclerometric measurements of the coatings made it possible to establish a high adhesion strength of the coatings. © 2014 Springer Science+Business Media New York.


Ermolaev I.S.,Technological Institute of Superhard and New Carbon Materials | Ermolaev V.S.,Russian Federation OOO | Mordkovich V.Z.,Russian Federation OOO
Theoretical Foundations of Chemical Engineering | Year: 2013

Process flow schemes of the production of liquid hydrocarbons from natural gas were considered. Based on the proposed flow schemes, a mathematical model of the process was constructed. The overall material balances and energetic characteristics of the process were calculated. The application of recirculation circuits was shown to have high target product yields per unit feedstock gas. © 2013 Pleiades Publishing, Ltd.


Glezer A.M.,RAS Institute of Metal Physics | Sundeev R.V.,Bardin Central Research Institute for The Iron And Steel Industry | Shalimova A.V.,Bardin Central Research Institute for The Iron And Steel Industry | Useinov S.S.,Technological Institute of Superhard and New Carbon Materials
Russian Physics Journal | Year: 2012

The structure evolution of the Zr 50Ni 18Ti 17Cu 15 massive metal glass upon megaplastic strain (MPS) in the Bridgeman chamber is investigated in a wide interval of strain degrees at room temperature. It is demonstrated that upon MPS with n = 1/2 rotation of the Bridgeman anvil, nanocrystalline phases are precipitated in the alloy. With increasing strain, these phases are dissolved. It is suggested that nucleation centers of nanocrystalline phases (nanoclusters) are formed in the amorphous matrix upon MPS under compression without shear in the Bridgeman chamber. These phases grow in the shear bands transforming into the nanocrystalline phase upon MPS. © 2011 Springer Science+Business Media, Inc.


Gogolinskii K.V.,Technological Institute of Superhard and New Carbon Materials | Gubskii K.L.,National Research Nuclear University MEPhI | Kuznetsov A.P.,National Research Nuclear University MEPhI | Reshetov V.N.,National Research Nuclear University MEPhI | And 4 more authors.
Measurement Techniques | Year: 2012

The structure and operating principle of the NanoSkan-3Di scanning probe microscope are briefly described. An investigation of the metrological characteristics of this measuring system using linear TGZ-type gratings demonstrated the high level of reproducibility of the measurements and showed that the results agree with the data obtained in a calibration at the PTB (Germany). © 2012 Springer Science+Business Media, Inc.


Derevich I.V.,Moscow State Technical University | Ermolaev V.S.,Moscow State University of Environmental Engineering | Zolnikova N.V.,Moscow State University of Environmental Engineering | Mordkovich V.Z.,Technological Institute of Superhard and New Carbon Materials
Theoretical Foundations of Chemical Engineering | Year: 2011

The method of pseudocritical thermodynamic parameters and the Lee-Kesler equation of state are used for calculating the thermal and physical properties of a solution and a mixture of gaseous paraffins that are major constituents of Fischer-Tropsch synthesis products. The dynamic viscosities of a solution and a vapor are modeled using an original procedure proposed by the authors. A surface tension is calculated by the parachor method. The composition of liquid and gaseous products is found using a stable iteration scheme proposed by the authors. The model is tested by a comparison with experimental data from the literature for model mixtures of hydrocarbons. The results of calculating the composition and thermophysical properties of a mixture of paraffins that model the composition of synthesis products at different values of the chain propagation parameter, temperatures, and pressures are presented. © 2011 Pleiades Publishing, Ltd.


Derevich I.V.,Moscow State Technical University | Ermolaev V.S.,Moscow State University | Zolnikova N.V.,Moscow State University | Mordkovich V.Z.,Technological Institute of Superhard and New Carbon Materials
Theoretical Foundations of Chemical Engineering | Year: 2010

A model for calculating the viscosity of individual paraffins that constitute the major part of the products of the Fischer-Tropsch synthesis is developed on the basis of the fluctuation hypothesis of the formation of vacancies in the liquid phase. All of the thermodynamic parameters of a substance and the energy barrier of the formation of vacancies are calculated using the Lee-Kesler equation of state. The results of the calculations of the viscosity of heavy paraffins are compared with the experimental data from published works. © 2010 Pleiades Publishing, Ltd.


Volkov A.D.,Moscow State University | Kokshaiskii A.I.,Moscow State University | Korobov A.I.,Moscow State University | Prokhorov V.M.,Technological Institute of Superhard and New Carbon Materials
Acoustical Physics | Year: 2015

All independent second- and third-order elastic coefficients were measured in the isotropic polycrystalline aluminum alloy AMg6 (Al–Mg–Mn system) using the Ritec RAM-5000 SNAP SYSTEM ultrasonic automated complex operating in the pulsed mode. The third-order elastic coefficients were determined using the Thurston–Bragger method from the experimentally measured velocity of shear and longitudinal elastic waves in AMg6 alloy as a function of uniaxial compression. © 2015, Pleiades Publishing, Ltd.


Ermolaev V.S.,Technological Institute of Superhard and New Carbon Materials | Mordkovich V.Z.,Technological Institute of Superhard and New Carbon Materials | Solomonik I.G.,Technological Institute of Superhard and New Carbon Materials
Theoretical Foundations of Chemical Engineering | Year: 2010

A mathematical model of heat and mass transfer processes in the grain of the Fischer-Tropsch synthesis catalyst is presented that takes into account the effect of the capillary condensation of the products of the synthesis in the pores of the catalyst. The influence of capillary condensation on the processes of the diffusion transfer of heat and mass in the catalyst grain is analyzed using the proposed model. Dependences of the efficiency factor of the grain on the pressure and temperature of the process and the partial pressure of various components of a mixture are presented. The possibility of determining the optimum pressure and temperature of carrying out the process for the catalyst of a certain structure is shown. © 2010 Pleiades Publishing, Ltd.

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