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[en] The effectiveness of the zone recrystallization method in an electric field for hafnium refining have been physically substantiated and experimentally confirmed. The distribution of impurities along the ingot after refining with the variability of the electric field direction is investigated. It is shown that the application of this method makes it possible to obtain hafnium samples with purity of 99.85 wt.%.
[en] ZrN-phase coatings with a cubic lattice (NaCl structure type) were produced by the method of vacuum-arc evaporation of a Zr cathode in nitrogen atmosphere at pressures PN between 0.02 and 0.64 Pa. The pressure increase at a bias potential of -150 V leads to formation of the growth texture  or to appearance of the bitextural state with the axes  and . Additional pulsed-mode supply of high-voltage negative potential Uip 800...2000 V, with pulse duration of 10 μs and frequency of 7 kHz, stimulates the emergence of texture . At the substructure level, the Uip supply causes the microstrain relaxation and the crystallite size growth with increasing pressure. The observed changes are attributed to increased particle mobility and nitride formation activity under the action of Uip. The hardness increases with increasing pressure and reaches a value of 43 GPa. The Uip supply leads to a shift of the maximum hardness towards higher pressures
[en] Phase composition, structure, substructure, hardness and elastic modulus of vacuum-arc multilayer coatings of TiN/ZrN, obtained with different thicknesses bilayer periods at constant negative bias potential (Ub) -140 and -200, was investigated by X-ray diffraction, electron microscopy and microindentation. It is established that under the action of these potentials during the deposition of layers mononitrides ZrN and TiN formed the preferred orientation of crystallites (texture) with the  axis perpendicular to the plane of growth. Increasing the number of boundaries with decreasing thickness of periods leads to increased hardness of 45 GPa, which is much greater than the hardness as ZrN and TiN single-layer coatings
[en] For calculation of the single-channel nucleon-nucleon scattering a phase-functions method has been proposed. Using a phase-functions method the following phase shifts of np.. scattering numerically for "1S_0_-, "1P_1_-, "3P_0_-, "3P_1_-, :1D_2_-, "3D_2_-, "1F_3_-, "3F_3_-, "1G_4_-, "3G_4_- states are calculated. The calculations has been performed using realistic nucleon-nucleon Reid68 and Reid93 potentials. Obtained phase shifts for energy up to 350 MeV are in good agreement with the results obtained in the framework of other methods. Using the obtained phase shifts we have calculated the full cross-section np-scattering.
[en] The concentration of radionuclides in teeth of patients which have different odontogenic inflammatory processes by means of use Ge(Li)-detector was determined. Teeth are the important biological structure in the field of biomineralization. Teeth can use as a bio-indicator of the environment and nutritional status. The samples were collected from patients with odontogenic inflammatory processes in Kharkov region. The specific activity of "1"3"7Cs, "2"2"6Ra, "2"1"4Pb, "2"1"4Bi, "2"2"8Ac in teeth of patients with various odontogenic inflammatory processes was measured. The information obtained in this study indicate that environmental contamination by the radionuclide in resulted of the atmospheric nuclear weapons test in the 1960 years exceed by far that caused by the Chernobyl accident.
[en] The interest in the probability distribution function, which describes the position of a heavy charged particle and direction of motion in matter, while its initial and final coordinates and angles are known, relates to proton imaging that is currently developing actively. The modern approach to calculating proton trajectories and widths is based on an approximations (first made by Fermi) that were never explained or justified. In the present work, we study the origin of the above-mentioned approximations, present the full formula for the probability distribution function, and show a limitation of the method that appears in the case of full formula
[en] Capabilities of graphics processing units (GPU) and central processing units (CPU) have been investigated for realization of fast-calculation algorithms with the use of tabulated functions. The realization of tabulated functions is exemplified by the GPU/CPU architecture-based processors. Comparison is made between the operating efficiencies of GPU and CPU, employed for tabular calculations at different conditions of use. Recommendations are formulated for the use of graphical and central processors to speed up scientific and engineering computations through the use of tabulated functions
[en] The influence of preliminary diffusion oxidation on mechanical properties of ferritic steel SUH409L (Fe-11Cr) in oxygen containing lead melt (10"-"6...10"-"7 wt.%) in temperature range 400...600 "d"e"g C has been studied. Oxidation in the temperature range 600...800 "d"e"g C for 24...150 h results the formation of oxide films (1...4 μm). The thickness and composition of films depends on temperature and duration of oxidation. In particular, the increase in temperature leads to the increase in grain size of steel and the evolution of oxide's phase composition from magnetite to chromium-containing spinel and discontinuous formation of chromium oxide Cr_2O_3. The oxidation leads to decrease tensile strength and ductility of steel that correlates with increasing grain size. In lead the strength of pre-oxidized samples reduces. It manifests itself more significant for oxidation which leads to the maximum growth of grain sizes. It was evidence of that the presence of oxide layer limits direct contact between metal and lead that consequently prevents steel embrittlement. The oxidation which minimally affects on the grain sizes of steel (600 and 800 "d"e"g C within 24 hours) provides the minimal losses in plasticity in lead
[en] Nanostructured multilayered coatings TiN/ZrN with 134...533 layers and the average thickness of layers of 20...125 nm have been synthesized by means of vacuum-arc deposition method. Good planarity of the layers obtained in nanometer scale from plasma flows in reaction medium has been revealed. As a model of critical working conditions of the coatings, the mechanisms of structural and phase changes in surface layers at conditions of influence of aggressive oxygen atmosphere at high temperature (700 "d"e"g C) have been determined. The influence of thickness parameter of multilayered system on its hardness has been shown. It has been determined, that the highest hardness of 42 GPa and the lowest abrasive wear of the coating 1.3·10"-"5 mm3"·N"-"1·mm"-"1 and the counter body 1.9·10"-"6 mm"3·N"-"1·mm"-"1 are inherent to the system TiN/ZrN with the minimal thickness of the layers of 20 nm in a period. The obtained results have been explained by the influence of dimensional factor of interphase borders, which is multiply enhanced in multilayered system with the nanometer scale thickness of the coatings
[en] Represented results are based on using the 197Au(γ,γ')197mAu reaction, the experimental integrated cross sections of the isomer excitation through activation levels and the Monte-Carlo simulation method. It is shown that applying of high-current electron accelerator (EA) with energy 8.7 MeV permits to determine the threshold of gold definition in nature and technological materials ≥ 0.1 g/t