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Vestnik NSU. Series: Physics. 2012. V7, i 2 |
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Quantum Optics, Quantum Electronics |
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Zharkova G. M., Petrov A. P., Streltsov S. A., Khachaturyan V. M. Polarization Holographic Gratings on Polymer Dispersed Liquid Crystals The formation of switchable polarization gratings and their properties are presented. The grating structures are created in polymer-liquid crystal composite by recording the interference pattern generated by two coherent laser beams with orthogonal polarization. The influence of the regime of formation, composition of composite and the azimuthal angle of the polarization of probe beam on the diffraction effectiveness of such grating are investigated. Electro-optical effects are studied, the possibility of the thermal-optical switching of grating are demonstrated. |
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High-Energy and Accelerator Physics, Physics of High-Temperature Plasma |
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Listopad A. A., Davydenko V. I., Ivanov A. A., Mishagin V. V., Uhlemann R., Schweer B. Multislit Four-Electrode Ion-Optical System for Fast Atomical Diagnostic Beam Formation For the formation of a narrow atomic diagnostic beam the providing of small angular divergence is fundamentally
important issue. When using a slit geometry angular divergence of the beam in the direction along the slit is mainly |
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Physics of Field, Neutral and Ionized Gases |
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Mullyadzhanov R. I., Yavorsky N. I. Submerged Jet of a Conducting Fluid in the Presence of the Magnetic Field We consider a steady flow of a viscous incompressible conducting fluid. New exact solution of the magnetohydrodynamic (MHD) equations is obtained, when the flow is induced by the point source of hydrodynamic momentum located at the end of a semi-infinite linear conductor with a set value of the electric current. The effects of the confinement of the current density and the loss of existence of the solution with the finite values of electric current and various values of the Reynolds number and the Batchelor number (magnetic Prandtl number) are found. The non-self-similar problem is considered, when the flow is induced by the point source of momentum, angular momentum, flow rate and electric current that are set at the origin. In this case, the first term of the asymptotic expansion of the velocity at the infinity is described by the exact solution of the Navier – Stokes equations of the submerged jet (Slezkin – Landau – Squire solution). We analyze the conservation laws. It is shown that the induced magnetic field reduces the intensity of the jet flow. |
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Lysenko V. I., Trufanov D. Yu., Bardakhanov S. P. Separation of Gases by Nanoporous Ceramics On basis of silica nanopowder «tarkosil» (produced by the authors through new technology of raw material evaporation by electron beam), the nanoporous ceramics with open porosity were used, and its separation properties were studied. For the ceramics, obtained at different sintering temperatures, their specific surface, porosity, and separation factor were determined. The obtained ceramics were applied for separation of four combinations of gases: He/Ar, He/N2, He/CH4, and N2/Ar. The possibility (using the created by the authors ceramics) of helium enrichment his mixtures with more heavy gases was shown. |
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Abdurakipov S. S., Dulin V. M., Markovich D. M. Spatial Structure of Large-Scale Vortices in a Swirling Jet with Breakdown and Precession of the Vortex Core An experimental study of 3D spatial structure of large-scale vortices in a strongly swirling turbulent jet was performed by using Particle Image Velocimetry (PIV) method and Proper Orthogonal Decomposition (POD) analysis. |
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Alekseev A. A., Zabaykin V. A., Tretjakov P. K., Naumov I. E. Research of Thermal Durability of Materials in High-Speed Flows In this paper, the thermal stability of heat-resistant alloy samples and composite materials at long-term effect of hightemperature high-speed flow (up to their destruction) was investigated. During the tests the local surface temperature in the most heat-stressed areas was measured. Estimations of heat flows to the surface of the samples on transition to the stationary mode have been made. |
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Anokhina E. S., Dekterev D. A., Shtork S. I., Alekseenko S. V. Investigation of Stationary Vortex Structures in the Model Combustion Chamber This work focuses on experimental and numerical study of stationary vortex structures in a model of vortex combustion chamber of the tangential type. The experiments included the visualization of vortex structures in the work area using a laser light source and a digital high-definition cameras. The calculations were performed using a commercial package STAR-CCM +. From known turbulence models have been chosen the most suitable for the problem under investigation. In the calculations we obtained results that agree well with experimental data, which confirms the adequacy of employed numerical model. |
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Tolkachev S. N., Gorev V. N., Zharkova G. M., Kovrizhina V. N. Experimental Techniques of the Study of the Vortex Disturbances Structure Caused by Point Injection on the Swept Wing Leading Edge The article contains the results of thermoanemometry on the curvilinear surface and liquid crystal thermography techniques for the investigation of the flow stability on the swept wing leading edge. The numeric results of the velocity disturbance distribution in the boundary layer near the attachment line were received with a help of the thermoanemometry technique. It was found out, that the boundary layer become less stable, when a stationary vortex modifies the flow. The liquid crystal thermography technique allowed to expand the workspace for investigations up to 70? from the attachment line, to receive the visualization pictures of disturbed flow for several regimes of blowing, to reveal an influence of the blow velocity on dimensions and trajectory of stationary disturbances, which were induced by injection. The results of visualizations are in a good agreement with thermoanemometry results. |
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Tolkachev S. N., Gorev V. N., Kozlov V. V. The Investigation of Stages of Cross Flow Instability
Developing on the Leading Edge of the Swept Wing by Liquid-Crystal Thermography The liquid crystal thermography technique was tested for the investigation of stages of stationary disturbance developing after the roughness element and for indication of turbulence on the swept wing leading edge. It was shown, that stationary disturbance is easy to excite by the roughness element, develops along the streamline. The stationary behavior dependence from the roughness element size was investigated. It was determined, that the turbulence doesn’t develop along the leading edge in the explored speed range. |
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Korobeishchikov N. G., Zarvin A. E., Kalyada V. V., Khodakov M. D. High Intensity Argon Cluster Beams Formation for Technological Processes Modernization of experimental complex LEMPUS-1 was done. Experimental investigations of argon cluster beams formation for ion-cluster surface modification technology were performed. Intensity of cluster beams up to 5*10^14 clusters per cm2 per sec with average cluster size about 1300 was obtained. It was found the optimal conditions for cluster beam formation. |
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Solid-State and Semiconductor Physics, Physics of Nanostructures |
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Panchenko A. V., Alekseev A. V., Gromilov S. A. Development of Debye – Scherrer Method for Study of Polycrystalline Samples A quick test has been proposed for the refinement of the unit cell parameters of polycrystalline samples including massive those with a large absorption coefficient. The Debye – Scherrer scheme used as the basis was realized on a Bruker X8APEX diffractometer (MoK? radiation, the plate two-coordinate CCD detector position 2? ? 90?, the resolution 1 024 x 1 024, accumulation time 15 min). External standards were ?-Al2O3 and Au. A polished section of the Ir0.85Re0.15 metal tablet was studied. The measurement precision of the unit cell parameter, afcc = 3.8470(4) A, was confirmed by studying the sample in the Bragg-Brentano geometry. |
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Vanina P. Yu., Gromilov S. A. Improving of Accuracy of Measurements of Unit Cell Parameters by Diffraction Reflections at Small Angles The main purpose of the work is the improving of accuracy of the unit cell parameters the measurements by diffraction
data at small angles. The basis of this approach is creating of new laboratory standard, which is the mixture of the |
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Borisov G. M., Kovalev A. A. Investigation of Method for Determining the Optical Parameters Based on the Measurement of Angles of Incidence A method of determining the real and imaginary parts of the refractive index n(?) and ?(?) of thin layers in semiconductor heterostructures is proposed. The method is based on the measurement of angles on the two characteristic curves of the reflection from the sample formed from the substrate heterostructure grown on top of it, for p-polarized wave. The first characteristic angle ?? is an analogue of the Brewster angle, the second angle ?? corresponds to the inflection point of the curve. Measurements of ?? and ?? are carried out for two samples grown on GaAs. An algorithm for extraction from measurements the n (?) and the ? (?) of the quantum wells layers in heterostructures is proposed and tested. |
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Educational and Methodical Provision of Teaching of Physics |
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Zamuraev V. P., Kalinina A. P. About Conditions of Equilibrium And Stability of Thermodynamic Systems The clear statement of a problem on balance and stability of thermodynamic systems is given. In these frameworks a number of important thermodynamic inequalities, a condition of phase equilibrium process is received. The critical phenomena are considered. |
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