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61.
62.
The effects of W and Mo surface crystalline texture on the angular distribution of sputtered atoms were investigated experimentally and by computer simulation. A small-sized planar DC magnetron was used to sputter the target by 200–300 eV Ar+ ions. The crystalline texture was formed under rolling of metal foils and during the preparation of metal bars and was controlled by X-ray diffraction analysis. For W and Mo foils, a strong anisotropy of the angular distribution was found. The character of angular distribution was different in the planes oriented perpendicularly and in parallel to the direction of rolling. In the first case, the angular distribution was peaked at the polar angle θ=0, while in the second case, the angular distribution, in addition to a maximum at θ=0, revealed a pronounced maximum at θ≈ 57° and ≈60° for Mo and W, respectively. For bars, no azimuthal anisotropy was observed, but the angular distribution was peaked at θ=37° (Mo) and θ=45° (W). This is in contrast to the case of non-textured Mo and W polycrystals, for which the angular distribution had a maximum at θ=0. Computer simulation technique in combination with the results of X-ray analysis was used to clarify the above experimental findings. It was demonstrated that the angular distribution of sputtered atoms can be successfully used for the determination of the crystalline texture of metals. 相似文献
63.
A.V. Martynenko 《Applicable analysis》2013,92(9):1863-1888
We study the Cauchy problem for quasilinear parabolic equation with inhomogeneous density and a source. We show that this problem has a global solution under the assumptions that initial datum is small enough in the integral sense and the source term has overcritical behaviour. The sharp estimates of a solution is obtained as well. 相似文献
64.
Zolochevskyi O. O. Parkhomenko L. O. Martynenko O. V. 《International Applied Mechanics》2021,57(3):336-346
International Applied Mechanics - A physical model for describing the diffusion creep in perovskite-type material given oxygen non-stoichiometry and tensile–compressive asymmetry is... 相似文献
65.
I. L. Balikhin E. N. Kabachkov E. N. Kurkin V. M. Martynenko V. N. Troitskii I. A. Domashnev E. Yu. Upryamova E. M. Shifman A. M. Ovezov 《High Energy Chemistry》2018,52(4):360-363
The product composition of photocatalytic oxidation of vaporized sevoflurane, a next-generation fluorinated inhalation anesthetic, has been studied. It has been found that the final products of oxidation are carbon dioxide and hydrogen fluoride. The possibility of complete chemical absorption of the evolved hydrogen fluoride by a lime absorber during the course of the photocatalytic reaction has been shown. A safe scheme for using photocatalysis is recommended for purifying air to remove vapors of halogen-containing anesthetics under medical hospital conditions. 相似文献
66.
Olga A. Kraevaya Alexander S. Peregudov Vyacheslav M. Martynenko Pavel A. Troshin 《Tetrahedron letters》2018,59(7):605-607
The chlorofullerene C60Cl6 was demonstrated as a versatile precursor for the synthesis of two isomerically pure fullerenols via tetrabutylammonium bromide promoted reactions with water. Performing the synthesis in wet chlorobenzene produced 1,4-C60(OH)2 as the only isolable product along with substantial amounts of non-functionalized C60. However, the addition of DMSO as a co-solvent altered the reaction pathway, leading to the formation of C60(OH)5Br as the main product. Both isolated compounds were novel and their molecular compositions and structures were confirmed by mass spectrometry and NMR spectroscopy. The fullerenol C60(OH)5Br, which was formed in a moderate yield, represents the first isomerically pure polyhydroxylated fullerene available on a large scale. 相似文献
67.
M. R. Menyashev A. I. Martynenko N. I. Popova N. A. Kleshcheva N. A. Sivov 《Polymer Science Series B》2016,58(5):556-563
New methods for the preparation of guanidine methacrylate, methacryloyl guanidine, and its hydrochloride have been proposed, and the physicochemical characteristics of the products have been studied. A number of kinetic parameters of the radical polymerization of these monomers have been determined (the rate and the rate constant in the initial section as well as the order of the reaction rate with respect to the concentration of the initiator for methacryloyl guanidine hydrochloride). It has been found that the classical general rules are followed: The conversion increases with an increase in temperature, while the characteristic viscosity decreases. The main NMR spectroscopic parameters of polymethacryloyl guanidine hydrochloride have been determined. According to preliminary biological tests, polymers have sufficiently high bactericidal activity and can be used as stand-alone biocidal preparations or as functional additives in composite materials. 相似文献
68.
69.
Small intervals of the hyperfine structure of the ground state in the muonic-lithium ions (μe36,7Li)+ were calculated by perturbation theory in the fine-structure constant and in the electronto- muon mass ratio. Vacuum-polarization, recoil, and nuclear-structure effects and electron vertex corrections were taken into account. The values obtained for the small hyperfine-splitting intervals can be used in a comparison with future experimental data and in tests of quantum electrodynamics. 相似文献
70.
A. V. Martynenko A. F. Tedeev 《Computational Mathematics and Mathematical Physics》2007,47(2):238-248
The following quasilinear parabolic equation with a source term and an inhomogeneous density is considered: . The conditions on the parameters of the problem are found under which the solution to the Cauchy problem blows up in a finite time. A sharp universal (i.e., independent of the initial function) estimate of the solution near the blowup time is obtained.
相似文献
$\rho (x)\frac{{\partial u}}{{\partial t}} = div(u^{m - 1} \left| {Du} \right|^{\lambda - 1} Du) + u^p $