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Goryainov Georgiy I., Karov Dmitry D., Polykarpov Yuri I., Slutsker Alexander I., Stepanov Andrey B.

Breaking durability parameters estimation for elastomers

Published in category «Condensed matter physics»

Breaking durability characterizes the operability of an object (an implant) made of certain material. Method is suggested to estimate poly(esterurethansiloxane) elastomer parameters such as interatomic bonds dissociation energy U0 and coefficient γ0 characterizing bond energy dissociation decrease by stress on basis of tension diagrams under tension rate variation.

Views: 2250 Comments: 0

Goryainov Georgiy I., Kapralova Victoria M., Loboda Vera V., Sarakuz Oleg N., Slutsker Alexander I.

Characteristics of 3D cross-linking in new poly(esterurethansiloxane) elastomers

Published in category «Condensed matter physics»

The densiquilibrium module measurements. Equilibrium swelling coefficients were investigated to confirm the formation of 3ty of cross-linking in segmented poly(esterurethansiloxane) elastomers have been obtained from stoichiometry of synthesis and quasi-eD cross-linking in new elastomers.

Views: 2066 Comments: 0

Matveev Sergey A., Denisov Sergey A., Chalkov Vadim Yu., Shengurov Vladimir G., Stepikhova Margarita V.

Growing and photoluminescence investigation of silicon-germanium structures doped with erbium on sapphire substrates

Published in category «Condensed matter physics»

Epitaxial SiGe:Er layers on sapphire substrates which have erbium photoluminescence at a wavelength of 1.54 microns have been obtained. The structural quality and the PL intensity dependencies of the layers on the growth parameters were studied.

Views: 1541 Comments: 0

Andreeva Nataliya V., Pestov Yuri I., Makin Vladimir S., Privalov Vadim E., Fotiadi Alexander E.

Controlled microcones formation on high refractory metals under multipulsed laser irradiation

Published in category «Condensed matter physics»

The problem of controlled formation of single tip-shaped micro- and nanostructures under the action of series of laser pulses have been considered. The possibility of production of tip-shaped bumps with heights up to 50 micrometers on the surface of high refractory metals under the action of the order of 100 submillisecond pulses have been experimentally shown.

Views: 2336 Comments: 0

Stepanov Andrey B.

The application of neural networks in the wavelet synthesis for the continuous wavelet transformation

Published in category «Simulation of physical processes»

The article analyses the basic principles of the wavelet synthesis for continuous wavelet-transformation with the use of artificial neural networks. Theoretical and practical substantiations for the choice of a mathematical apparatus are presented.

Views: 1938 Comments: 0

Seteikin Alexey Yu., Fotiadi Alexander E., Privalov Vadim E.

Simulation of laser radiation propagation in inhomogeneous media with complex geometries

Published in category «Simulation of physical processes»

A mathematical model has been developed. It makes possible to analyze the process of the three-dimensional propagation of laser radiation in inhomogeneous media with a complex geometry using the proposed modification of the Monte Carlo method. The model also allows to carry out the calculation of the distribution of the absorbed laser energy density in multilayered materials with complex geometry and can be used in solving problems of analysis of thermal fields visualization. Those problems arise in irradiated tissues.

Views: 2326 Comments: 0

Shamina Elena N.

The quantum and chemical investigation of the benzene solvent influence on the electronic structure of the carbon nanotubes

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

The article presents the semi-empirical quantum and chemical study of the processes of adsorption of benzene molecules on the surface of one-layer carbon nanotubes with varied diameters. The calculations were carried out on the basis of the model of molecular cluster with borderline pseudoatoms using semi-empirical MNDO/RM1 scheme. The adsorption process energy characteristics were determined.

Views: 1873 Comments: 0

Ipatov Andrey N.

Influence of interparticle interaction on the optical properties of fermionic systems

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

An influence of many-particle correlations in finite fermionic systems with equal numbers of opposite charge particles on their optical properties is discussed in the article.

Views: 2010 Comments: 0

Bykovsky Valery F., Molkov Sergey I., Stepanov Vladimir A., Khilov Vadim S., Khilov Sergey I.

igh power coherent light radiation source for optical holography and Raman spectroscopy

Published in category «Experimental technique and devices»

The problem of development of a high power coherent light radiation source for optical holography based on single frequency argon laser has been reviewed.

The conditions for obtaining single-frequency generation for a homogeneously broadened spectral line in the gas-discharge lasers with long resonators were determined. The possibility of realization of the single-frequency argon laser emitting in the blue-green range of the spectrum was demonstrated.

Views: 2142 Comments: 0

Molkov Sergey I., Savin Vasily N.

Influence of electron emission processes on the charge of dust particles in ordered plasma-dust structures

Published in category «Physical electronics»

In the article the influence of electron emission processes and roughness parameter on a dust particle electric charge are considered quantitatively and qualitatively.

Views: 1923 Comments: 0

Baksht Fedor G., Lapshin Vladimir F., Pelli Alexander V.

Radiative energy transfer simulations in axial-symmetric high pressure gas discharge plasma

Published in category «Physical electronics»

Direct integration method for radiative heat transfer calculation in the conditions of axial-symmetric high pressure gas discharge plasma is described. The comparison with results of calculation in the diffusion approach is made.

Views: 2070 Comments: 0

Dubov Victor V., Korablev Vadim V.

Slow electrons scattering by fluctuation potential of semiconductor

Published in category «Physical electronics»

The scattering of low-energy electrons by fluctuation potential near the semiconductor surface is considered. The results obtained can be applied the use of electronic high energy resolution spectroscopy to extract information about the structure of the semiconductor surface and near surface interactions by low energies. Special attention is paid to the case of high temperatures when there is asymmetry of the peak of the reflected electrons.

Views: 2214 Comments: 0

Dubov Victor V., Korablev Vadim V., Sugaipov Moldy S.

Resonance electron scattering by the surface of semiconductor with the natural nonuniformities

Published in category «Physical electronics»

The effect of different types of natural nonuniformities of the semiconductor surface on the characteristics of the surface resonance scattering of electrons at intermediate energies has been considered. Analysis was conducted both for the case of the nonpolarized particles and for the polarized electrons. It was shown that the processes of resonance surface scattering were sensitive to nonuniformities of surface potential. Therefore with a study of surface resonances in the general case it is also necessary to consider the effects of natural nonuniformities on the observed dependences and results.

Views: 2030 Comments: 0

Ilin Nikita V., Kiesewetter Dmitry V.

The numerical simulation of the light intensity distribution in proximity to the output end of optical fiber given the optical vortices

Published in category «Physical optics»

By the use of numerical simulation light intensity distributions have been obtained in proximity to the output end of optical fiber for the interference between the plane wave and the optical vortex of fiber. The main properties of those interference patterns such as helical type and their rotation during displacement of the observation plane were determined.

Views: 1847 Comments: 0

Kochetkova Anna S., Efimov Nikita Yu., Sosnov Evgeny A.

The investigation of PVC-based nanocomposites by atomic force microscopy

Published in category «Physical materials technology»

The morphology of surface of film composite materials based on PVC with injected nanodispersed Al2O3 (original and modified by phosphorus-oxide and silicon-organic structures) were investigated by Atomic Force Microscopy. The results were compared with the water vapor permeability of tested materials. It was suggested about the influence of the chemical nature of the filler surface on the water vapor permeability of the composite.

Views: 2085 Comments: 0

Yakunina Maria V., Vorontsova Darya N., Minakhin Leonid S.

Non-canonical RNA-polymerases of ϕKZ-like phages

Published in category «Biophysics and medical physics»

Nine ϕKZ-like bacteriophages, encoding their own RNA polymerase (RNAP), belonging to the class multi-subunit RNAP, were found in a database of complete genomes. Analysis of protein sequences and genetic environment of RNAP genes have suggested the presence of two independent functional phage RNAP, “virion” and “non-virion”.

Views: 1981 Comments: 0

Ivanov Nikolay A., Lebedeva Zhanna S.

Proton beam characteristics estimation for using in ophthalmology

Published in category «Biophysics and medical physics»

The accelerator C-80 for proton therapy of eye is under construction in B.P. Konstantinov PNPI. As a part of this project the protons beam delivery system with energies near 60 MeV was designed. The requirements to the beam characteristics were defined. We analyzed the beam delivery system and beam characteristics in Monte Carlo based system Geant4. The most accurate model of the description of physical processes was defined. Several variants of the system based on these models were calculated.

Views: 1757 Comments: 0

Pobegalov Georgiy E., Arseniev Anatoly N., Vedyaykin Alexey D., Sokolova Maria L., Fedorova Yana V., Sabantsev Anton V.

Changing of DNA molecule mechanical properties during interaction with YOYO-1 intercalating dye

Published in category «Biophysics and medical physics»

The method for registration of a single DNA molecule length change during interaction with a ligand is proposed. The method is tested in the case of DNA molecule interaction with intercalating YOYO-1 dye. The experimental data obtained signifies both DNA elongation and mechanical properties alteration upon YOYO-1 binding.

The proposed method can be used to study single DNA molecule interaction with different ligands, including dyes and DNA-binding proteins. Also this method can be used to study other biopolymers, including amyloid fibrils.

Views: 2085 Comments: 0

Pavlov Fedor F.

The calculation procedure of elastic scattering of a polarized nucleon on a polarized deuteron

Published in category «Nuclear physics»

The paper views a relativistic deuteron as a system of two nucleons (a two-nucleon approach) in a formal light cone description. The deuteron is considered as a superposition of two-nucleon Fock states with the invariant mass depending on the relative momentum in a proton-neutron pair. A procedure for consistent calculation of elastic scattering of a polarized nucleon on a polarized deuteron is shown.

Views: 2053 Comments: 0

Berdnikov Alexander Ya., Golovin Alexey V., Ivanishchev Dmitry A., Kotov Dmitry O., Ryabov Victor G., Ryabov Yuri G.

Yield of electrons from semileptonic decays of charm and bottom hadrons in proton-proton collisions at 200 GeV

Published in category «Nuclear physics»

The invariant transverse momentum spectrum of electrons from charm and bottom mesons decays in proton-proton collisions at 200 GeV is presented. The spectrum is compared with theoretical predictions.

Views: 1948 Comments: 0

Kozlov Vladimir N.

Operators for minimization of linear and nonsmooth functionals on compact sets

Published in category «Mathematics»

The paper discusses the operators for the analytical solutions of problems of linear functional minimization over compact sets in a finite-dimensional space. The geometric interpretation of the results is provided through the example of a compact set in a two-dimensional real vector space defined as an intersection of a linear variety and a sphere. The piecewise-linear optimization problems are formulated and proved to possess solutions taking a form of minimization operators. Non-smooth optimization problems have been transformed into convex programming problems.

Views: 1959 Comments: 0

Blistanova Lydia D., Kalyada Leonid G., Nechaev Alexey I., Strecopitova Maria V., Uzhegov Nikolay G.

The stability of conservative systems with cyclic coordinates

Published in category «Mathematics»

The given article focuses on the investigation for stability of conservative systems with cyclic coordinates. The problem on construction of controls maintaining the existence of diversity predetermined has been demonstrated to reduce to that construction maintaining the motion with the momentum predetermined.

Views: 2050 Comments: 0

Filipiev Roman A., Konovalov Sergey V., Gromov Victor Е.

Influence of contact effects on microhardness of metals

Published in category «Mechanics»

The influence of contact effects on microhardness of technically pure iron, tungsten and titanium is experimentally investigated. Nature of influence of attached zirconium and copper on microhardness of studied metals is compared. Spasmodic dependence of change of microhardness is established at influence of attached metal.

Views: 1745 Comments: 0

Khrabry Alexander I., Smirnov Evgeny M., Zaytsev Dmitry K.

Influence of turbulence model on the results of simulation of dambreak flow about an obstacle

Published in category «Mechanics»

The results of numerical simulation of a dambreak flow in the presence of a rectangular obstacle are presented. It is shown that computations without turbulence modeling overestimate the intensity of the wave formation. The k-e turbulence model yields higher turbulent viscosity, than SST model, and provides reasonable agreement with experimental data.

Views: 1990 Comments: 0

Nikulin Illarion L., Perminov Anatoly V.

Simulation of the induction processes in the conductive cylinder placed in the non-uniform variable magnetic field

Published in category «Radiophysics»

In this paper the mathematical model of generating of induction magnetic field, electric currents and Joule heat in conductive cylinder placed in non-uniform variable magnetic field is suggested. The results of the computational experiments are given and analyzed.

Views: 1821 Comments: 0

Karseev Anton Yu., Davydov Vadim V., Dudkin Valentin I.

The variation of the distilled water spin-lattice relaxation time in turbulent stream by the strong electrical field

Published in category «Radiophysics»

The problems of distilled water magnetizing for the heavy water production are considered. The simultaneous effect of constant magnetic and electric fields on the T1 spin-lattice relaxation time for distilled water at different temperatures are investigated experimentally.

Views: 1897 Comments: 0

Klekhta Nikolay S., Pleshakov Ivan V., Dudkin Valentin I.

Pulse operation of the nuclear spin system responses in a magnetic material with domain walls

Published in category «Radiophysics»

The questions related with the action of magnetic field pulses on the spin echo formation in a ferrite are discussed. The qualitative model of the observed phenomena is developed; the importance of the domain walls is shown. The results of the work should be useful for the improvement of the magnetic materials research technique.

Views: 2002 Comments: 0