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111.
V. T. Bublik S. Yu. Matsnev K. D. Shcherbachev M. V. Mezhennyi M. G. Mil’vidskii V. Ya. Reznik 《Physics of the Solid State》2003,45(10):1918-1925
Diffuse x-ray scattering (DXS) is used to study the formation of microdefects (MDs) in heat-treated dislocation-free large-diameter silicon wafers with vacancies. The DXS method is shown to be efficient for investigating MDs in silicon single crystals. Specific defects, such as impurity clouds, are found to form in the silicon wafers during low-temperature annealing at 450°C. These defects are oxygen-rich regions in the solid solution with diffuse coherent interfaces. In the following stages of decomposition of the supersaturated solid solution, oxide precipitates form inside these regions and the impurity clouds disappear. As a result of the decomposition of the supersaturated solid solution of oxygen, interstitial MDs form in the silicon wafers during multistep heat treatment. These MDs lie in the {110} planes and have nonspherical displacement fields. The volume density and size of MDs forming in the silicon wafers at various stages of the decomposition are determined. 相似文献
112.
A. I. Artem’ev D. N. Klochkov K. Oganesyan Yu. V. Rostovtsev M. V. Fedorov 《Laser Physics》2007,17(10):1213-1216
The spatial amplification of a wave in a magnetostatic undulator with noncollinear electron and laser beams is studied in the framework of the dispersion relation for single-frequency and collective regimes. The dependence of the gain on the electron beam width is estimated with regard to the spatial boundedness of the beams. The laser power threshold at which the selection with respect to the transverse velocity is possible is obtained for a free-electron laser without inversion. 相似文献
113.
V. F. Shkar’ V. P. Denisenkov A. M. Grishin A. A. Yalali S. I. Khartsev E. I. Nikolaev V. N. Sayapin 《Physics of the Solid State》2003,45(12):2334-2337
Bismuth iron garnet films prepared through electron-beam and laser-induced evaporation on (001)-oriented substrates of scandium gallium gadolinium garnet are investigated using ferromagnetic resonance. It is assumed that the additional minima observed in the angular dependence of the resonance field can be associated with the magnetic moment of bismuth ions. 相似文献
114.
115.
116.
M. S. Nikol’skii 《Computational Mathematics and Modeling》2007,18(4):420-431
We consider the behavior of bundles of optimal controls when the initial state of the system goes to some given vector. We
investigate three types of optimization problems: problems with fixed process length and a free right endpoint; problems with
fixed process length and a fixed right endpoint; time-optimal problems. The article is a review of recent results obtained
by the author.
__________
Translated from Nelineinaya Dinamika i Upravlenie, No. 4, pp. 301–314, 2004. 相似文献
117.
N. N. Koval’ Yu. F. Ivanov I. M. Goncharenko O. V. Krysina Yu. A. Kolubaeva K. A. Koshkin 《Russian Physics Journal》2007,50(2):146-152
Phase composition, defect substructure, and mechanical properties of the Ti-Si-N coating deposited on metal and ceramic-metal substrates by electroarc sputtering of the Ti-Si composite cathode in an ionized
nitrogen atmosphere are investigated by the methods of modern materials science. It is established that coatings so formed
with a thickness of ∼1–3 μm are superhard (Hv ∼ 50 GPa), and have the nanocrystalline structure (with crystalline sizes D = 7 nm) based on titanium nitride δ-TiN.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 46–51, February, 2007. 相似文献
118.
A. V. Porfir’eva G. A. Evtyugin E. Yu. Podshivalina L. I. Anchikova G. K. Budnikov 《Journal of Analytical Chemistry》2007,62(12):1180-1186
A new technique is proposed for detecting interactions between DNA and DNA autoimmune antibodies using a potentiometric sensor based on a glassy-carbon electrode modified with polyaniline and native DNA from chicken erythrocytes. It is shown that the DNA-antibody interaction changes the rate of polyaniline doping in transferring the DNA sensor from an alkaline (pH 7.5) solution, which is optimum for the immunochemical reaction, to an acidic (pH 3.0) solution. The dynamics of the variation of the DNA sensor potential depends on the titer of antibodies and their origin. The dependence of the DNA sensor signal on the dilution of the blood sera from systemic lupus erythematosus and autoimmune thyroiditis patients shows that DNA antibodies can be diagnosed by the characteristic maximum in the dilution curve found in the range of serum dilutions from 1: 20 to 1: 50. 相似文献
119.
D. A. Kosmodem’yanskii 《Moscow University Mathematics Bulletin》2007,62(2):56-60
Spectral properties of the following three homogenized problems in the mechanics of strongly nonhomogeneous media are considered: the “double porosity” problem, the oscillation problem for a mixture of two viscous compressible liquids, and the oscillation of a medium consisting of an elastic frame and a viscous liquid. For all three cases results on the structure of the spectrum and on the existence of so-called “spectral gaps” are obtained. 相似文献
120.
O. V. Il’in 《Journal of Mathematical Sciences》2007,141(1):1041-1047
We describe W-geometry of two-dimensional Toda systems associated with the Lie algebra C
n
.
__________
Translated from Fundamental’naya i Prikladnaya Matematika (Fundamental and Applied Mathematics), Vol. 11, No. 1, Geometry,
2005. 相似文献