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Blagih Nikolai M., Nemov Sergei A., Shelimova Liudmila E.

The anisotropy of the transverse Nernst — Ettingshausen effect in PbSb[2]Te[4] monocrystal doped with copper

Published in category «Condensed matter physics»

The results on temperature dependence (80 — 450 K) of the Nernst — Ettingshausen tensor components (NETC) and on the Hall tensor (77 K) measured in PbSb[2]Te[4]:Cu perfect monocrystal have been presented. A considerable influence of the copper impurity on the holes concentration and the NETC right up to a sign change was found.

Views: 1273 Comments: 0

Tsyuk Alexander I., Voronenkov Vladislav V., Gorbunov Ruslan I., Latyshev Philipp E., Bochkareva Nataliya I.

Growth modes of HVPE gallium nitride films

Published in category «Condensed matter physics»

The effect of growth parameters on stress in thick GaN films grown on sapphire by HVPE method has been investigated. We have found two modes of growth with different growth stress. Films grown in one mode have rough surfaces and low stress. The second mode leads to smooth surfaces but the films contain many cracks due to high growth stress. A combination of these modes allows growth of films without cracks and with smooth surfaces.

Views: 1320 Comments: 0

Voronenkov Vladislav V., Tsyuk Alexander I., Zubrilov Andrei S., Lelikov Yuri S., Shreter Yuri G.

Mechanical stresses in gallium nitride films grown on substrates with a mask

Published in category «Condensed matter physics»

Noncontinuous GaN films grown on substrates with a mask by HVPE technique have been investigated. Mechanical stresses in the films were lower than in continuous ones of the same thickness. Stress reduction caused the film bending to decreese and declined the probability of cracking.

Views: 1170 Comments: 0

Snegirev Aleksandr Yu., Sazhin Sergei S., Talalov Victor A.

The effect of nonuniform temperature distribution inside a vaporizing liquid droplet

Published in category «Simulation of physical processes»

Three transient phases of droplet heating (cooling) and evaporation are identified. Using characteristic time scales, the dimensionless criteria have been formulated to identify the regimes in which the temperature gradient inside the droplet is significant and should be taken into account. The effect of the internal temperature gradient on droplet evaporation dynamics and the droplet life time has been investigated. This effect is demonstrated in numerical simulations of two distinct liquids (acetone and water) at low (20 °C) and high (1400 °C) ambient temperatures.

Views: 1505 Comments: 0

Andreeva Alena V., Zyn Vladislav I., Safonov Alexander A., Shatsky Alexander V., Shterenberg Alexander M.

Kinetics of the prepolymerization in nonstationary glow discharge

Published in category «Simulation of physical processes»

The method of analysis of kinetic data obtained in closed plasma chemical system with continuous mass spectrometric control of the molecular gaseous components is presented. The data contain two aspects of information about the system: the general structure of the kinetic picture with its ordering of the kinetic curves and the curves themselves.

Views: 1200 Comments: 0

Stepanov Andrey B.

Synthesis of wavelets for continuous wavelet transform of electroencephalography signals

Published in category «Simulation of physical processes»

The paper shows the main principles applied to the synthesis of wavelets for continuous wavelet transformation of electroencephalography signals. The research gives theoretical and practical foundation for the selection of the method for the particular type of features. A quantitative and qualitative evaluation of the results is provided.

Views: 1109 Comments: 0

Bagraev Nikolai T., Brilinskaya Elena S., Danilovskii Eduard Yu., Klyachkin L.E., Malyarenko Anna M., Romanov Vladimir V.

Magnetic properties of cadmium fluoride nanostructures

Published in category «Atom physics and physics of clusters and nanostructures»

Temperature- and field-dependent static magnetic susceptibility demonstrates the high temperature de Haas — van Alphen oscillations in the sandwich-nanostructures. Periodic frequency changes and the diamagnetic reply of the de Haas — van Alphen oscillations are registered for the first time by varying the temperature value, which reveal the synchronic temperature oscillations of the sheet density and the effective mass value of 2D holes as a result of the mesoscopic properties for the δ-barriers.

Views: 1303 Comments: 0

Vorobjev Leonid E., Panevin Vadim Yu., Sofronov Anton N., Melentyev Grigori A., Vinnichenko Maxim Ya., Dvurechenskiy Anatoly V., Yakimov Andrei I.

Photoinduced absorption in structures with Се/Si quantum dots

Published in category «Atom physics and physics of clusters and nanostructures»

Photoinduced optical absorption in undoped Ge/Si quantum dots structure has been studied in mid-infrared range under interband photoexcitation of nonequilibrium charge carriers. Photoinduced absorption spectra have polarization-dependent features related to intraband optical transition between discrete levels of holes energy spectrum. Absorption related to optical transitions from excited quantum dot states was observed for the first time in Ge/Si quantum dot structures.

Views: 1485 Comments: 0

Khodorkovskii Mikhail A., Murashov Sergey V., Lubchik Svetlana B., Rakcheeva L.P., Artamonova Тatiana О.

Features of processes of molecules clasterization during laser ablation

Published in category «Atom physics and physics of clusters and nanostructures»

The paper is devoted to investigation of interaction of pulse laser radiation with solid fullerene samples using time-of-flight mass-spectroscopy. The analysis of time dependences of cluster distributions of fullerene ions during an initial stage of expansion of an ablative torch, has allowed to explain the formation mechanism of fullerene clusterization in laser evaporation.

Views: 1376 Comments: 0

Kozlov Vladimir N., Trofimov Pavel A., Akimov Alexei I.

Simulation of a heating process in the plant used to longerons production

Published in category «Mathematical physics»

The nonsteady problem of allocation of heat in the course of a heating of the plant applied at manufacturing of longerons is solved. The Hankel transformation for a closed interval at the solution is used.

Views: 1392 Comments: 0

Denisov Alexander V.

One-dimensional problem of dispersion of the flat wave by the symmetric plasma layer

Published in category «Mathematical physics»

The problem about dispersion of a flat harmonious wave of vertical polarization by infinitely extended symmetric isotropic plasma layer with small losses is considered. Frequency of a wave is necessary to equal maximum plasma frequency of a layer, it is shown that at almost normal falling of a wave on a layer with hade change sharp reduction of factor of passage of a wave takes place.

Views: 1215 Comments: 0

Koroteev Anatoly A.

Computation methods for regularities of forming holes in output channels of systems for electron beam transport

Published in category «Experimental technique and devices»

The paper considers methods for complex modeling of regularities of forming holes in graphite diaphragms joining the pressure stages in compact systems for transporting the electron beams from vacuum to the area with pressure levels up to atmospheric ones.

Views: 1113 Comments: 0

Kudryashov Alexei V., Liokumovich Leonid B., Medvedev Andrei V.

Efficiency improving of the sound pressure transformation in fiber interferometric microphones

Published in category «Experimental technique and devices»

The principles of creating of fiber optic transducers for sensitive elements for fiber interferometer acoustic gauges (microphones) are considered. The results of measurements of the transducer with fiber interferometer arms spooled at inner and outer elastic cylinder surfaces that validate the effectiveness of this design are discussed.

Views: 1136 Comments: 0

Krasnova Nadezhda K., Martsynovskiy Ivan A.

The synthesis of electrostatic energy analyzers by inverse problems of dynamics

Published in category «Physical electronics»

Several algorithms have been developed to design electrostatic systems analyzing energy of charged particles and having characteristics predetermined and useful for the analysis. The approaches based on inverse problems solution using Hamilton — Jacobi equation and the Abel integral equation are illustrated with a variety of examples.

Views: 1163 Comments: 0

Martsynovskiy Ivan A.

Methods of energy spectrum reconstruction in electrostatic analyzers

Published in category «Physical electronics»

In the paper we focus on hardware function and investigate relation between energy spectrum of a particle source and current on a detector, which is given by hardware function. Then we propose several methods of energy analyzer resolution improving which may be achieved by reconstruction of the real source energy spectrum. The reconstruction is based on integral equation solution where hardware function represents kernel.

Views: 1119 Comments: 0

Mokrushin Yuri M.

The line imaging in the acousto-optical system with the laser pulsed

Published in category «Physical optics»

The task of the 2D image formation of line is considered in the acousto-optical system composed of the pulsed laser and the modulator based on the TeO[2] crystal. The frequency-contrast characteristics of this system and cross-section distribution of light intensity in the line was calculated for various values of the light pulse duration, the carrier ultrasonic frequency, the length of acousto-optical interaction, and the pitch angles of light.

Views: 1050 Comments: 0

Golikov Pavel A., Zolotorevsky Nikolai Yu., Vasilyev Alexander A.

Kinetics modeling of austenite transformation in steels with ferrite-perlite structure

Published in category «Physical materials technology»

The mathematical model of α -> γ transformation has been developed using the analysis of austenite growth mechanisms in the ferrite phase and the pearlite colonies accordingly. The model takes into consideration the peculiarities of austenite nucleation and growth within the initial microstructure of low and mediate carbon steels. Empirical parameters of the model are determined using available experimental data on the austenitization kinetics in steels of various compositions.

Views: 1128 Comments: 0

Hrushchenko Alexander A., Arefyev Konstantin M.

Sickness in the human lungs: simulation possibilities

Published in category «Biophysics and medical physics»

The pattern suggested before for gas exchange in human lungs, and also of its influence on illnesses processes has been amplified. The experimental and calculated data on pressure of oxygen in alveolar blood for two clinical cases were compared. The possible reasons for unhealthy status and its influence on gas exchange are shown.

Views: 1206 Comments: 0

Sulatskaya AnnaI.

Details of fluorescent thioflavin T dye interaction with amyloid fibrils

Published in category «Biophysics and medical physics»

This work is devoted to studying of amyloid fibrils structure with benzothiazole thioflavin T (ThT) dye. Our data prove that ThT molecules incorporate in amyloid fibrils in monomeric form and there is no ground to suppose the formation of ThT dimers, eximers, or micells. Information concerning ThT — amyloid fibrils binding parameters and spectral properties of bound dye was obtained by absorption spectrophotometry of solutions prepared by equilibrium microdialysis.

Views: 1031 Comments: 0

Zacharova Margarita A., Polyakova Irina V., Groshikova Anna R., Pisarev Oleg A., Panarin Evgeniy F.

Molecular recognition of glucose by artificial receptors of imprinted polymeric network

Published in category «Biophysics and medical physics»

The nature of intermolecular interactions between glucose and a molecularly imprinted polymeric sorbent — gl-MlP has been investigated. The sorption isotherms and thermodynamic functions testified to energetically heterogenous distribution of glucose in the sorbent phase. The contribution of specific binding to the equilibrium factors of the distribution and the change of the glucose sorption free energy increased in the physico-chemical conditions the closest to the gl-MlP synthesis conditions.

Views: 1220 Comments: 0

Berdnikov Yaroslav A., Ivanishchev Dmitry A., Kotov Dmitry O., Ryabov Victor G., Ryabov Yuri G., Samsonov Vladimir M.

K[s]-meson production in d + Au collisions at center-of-mass energy of 200 GeV per nucleon pair

Published in category «Nuclear physics»

We report K[s]-meson transverse momentum spectra and nuclear modification factors in d + Au collisions at center-of-mass energy of 200 GeV per nucleon pair. The comparison with other hadrons production results and the theoretical predictions are shown and discussed.

Views: 1317 Comments: 0

Berdnikov Yaroslav A., Ivanishchev Dmitry A., Kotov Dmitry O., Ryabov Victor G., Ryabov Yuri G., Samsonov Vladimir M.

The measurement of main characteristics ofpions, kaons and protons in heavy ion collisions at 62.4 GeV

Published in category «Nuclear physics»

π-, K-mesons and protons resulting spectra and nuclear modification factors measured in p+p, Cu+Cu and Au+Au collisions at √S[NN] = 62.4 GeV have been presented. Comparison with nuclear modification factors measured for π-mesons and protons in Cu+Cu and Au+Au collisions at √S[NN] = 62.4 GeV was carried out. The domination of jet-quenching effect over Cronin effect was shown to happen in the energy range between 22.4 and 62.4 GeV.

Views: 1434 Comments: 0

Pavlov Fedor F.

An estimation of a relativistic correction to the mean helicity of a proton in a deuteron

Published in category «Nuclear physics»

The paper views a relativistic deuteron as a system of two intensively interacting nucleons (a dinucleon approaching) in a formal description of the light cone. The article further deals with the calculation procedure about a mean helicity of a proton in a deuteron within variables of the light cone. This article calls attention to the estimation of a relativistic correction to the mean proton helicity in a deuteron by way of application of available modern realistic deuteron wave functions.

Views: 1062 Comments: 0

Berdnikov Yaroslav A., Zhalov Mikhail B., Rebyakova Victoria A.

Hard Donnachie — Landshoff pomeron in coherent ρ-meson photoproduction at small momentum transfered

Published in category «Nuclear physics»

We calculate the cross sections of coherent ρ-meson photoproduction in the terms of Donnachie — Landshoff (DL) model for experimental data description on HERA. Examination of coherent light vector meson production with high rapidities in proton-nuclear collisions on Large Hadron Collider allows to answer the question whether it is necessary to take in account the contribution of hard pomeron exchange for the soft interaction description in DL-model.

Views: 1382 Comments: 0

Tsaregorodtseva Ekaterina D.

Constructing of neural network emulator for control object

Published in category «Mathematics»

The paper describes the constructing of control object emulator, based on using of the neural network — multilayer perceptron and the genetic algorithm. Computation results are given for various control objects.

Views: 1028 Comments: 0

Avdeeva Marina B., Zubov Sergei V., Strecopitova Maria V., Peshekhonov Konstantin A.

The last multiplier and integral invariant

Published in category «Mathematics»

The conditions of integral invariant existence have been considered and the 'global' behaviour of solutions of differential equations system have been investigated. The infinity interval of the behaviour is implied.

Views: 1248 Comments: 0

Perminov Anatoly V., Shulepova Evgenia V.

High-frequency vibration influence on the convectional flow of non-Newtonian liquid

Published in category «Mechanics»

This article is devoted to thermal vibration convection studying in the non-Newtonian liquid type. In this work these equations of average liquid flow were obtained for Williamson's model and Ostwald — de Will's model. Quasy-equilibrium condition for non-Newtonian liquid in an arbitrary shape hollow was formulated. On the base of rheological Williamson's model a problem of vibration convection flow of nonlinear-viscous liquid in flat infinite vertical layer was considered.

Views: 1249 Comments: 0

Yablokova Alina E., Kargaltsev Oleg Yu., Bykov Andrey M., Pavlov Georgiy G.

A search for radio nebulae around pulsars PSR J0358+5413, PSR J1809-1917 and PSR В1800-21

Published in category «Astrophysics»

Radiointerferometric data on pulsars PSR J0358 + 5413, PSR J1809 - 1917, and PSR B1800 - 21 obtained with VLA are reduced with CASA and A1PS tools. An analysis of the results and their comparison with observations in other bands is given. Additional multichannel observations of the objects with EVLA are necessary to conclude on their nature.

Views: 1399 Comments: 0