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91.
Yu. B. Afanas’ev E. V. Mokrushina A. A. Nechitailov V. V. Prokof’ev 《Technical Physics Letters》1997,23(3):181-183
The parameters of Bi12TiO20 crystals grown with bismuth oxide of different degrees of purity were measured by a holographic recording technique in an
external ac electric field and were compared with a crystal specially doped with chromium. Various crystal parameters such
as the diffusion length of the photoexcited carriers and the Debye screening length were determined. It was found that the
absorption spectrum of the material and the holographic recording efficiency were strongly influenced by light chromium doping
and by insufficient purity of the starting mixture.
Pis’ma Zh. Tekh. Fiz. 23, 27–32 (March 12, 1997) 相似文献
92.
93.
94.
I. V. Gervas’eva D. P. Rodionov Yu. V. Khlebnikova N. F. Vil’danova A. S. Shtyrlov G. A. Dosovitskii A. R. Kaul’ 《The Physics of Metals and Metallography》2007,103(6):600-608
The texture, structure, and magnetic and mechanical properties of thin ribbons of nickel-palladium alloys have been studied. It has been demonstrated that in Ni94Pd6 and Ni92.5Pd5W2.5 alloys, a sharp cube texture can be formed that is stable up to rather high annealing temperatures. Segregation of palladium atoms to surface layers of ribbons has been found, which gives additional advantages for using these ribbons as substrates for epitaxial deposition of high-temperature superconductors. 相似文献
95.
E. S. Gorkunov S. Yu. Mitropol’skaya A. M. Povolotskaya 《Russian Journal of Nondestructive Testing》2005,41(3):175-181
Stacks of steel plates having different values of magnetic hardness and separated with nonferromagnetic gaps are investigated. The coercive force and the residual magnetic induction of a stack measured in a closed magnetic circuit depend on the layout of the plates in the stack and on the thickness of nonmagnetic gaps between them.__________Translated from Defektoskopiya, Vol. 41, No. 3, 2005, pp. 55–62.Original Russian Text Copyright © 2005 by Gorkunov, Mitropol’skaya, Povolotskaya.Dedicated to the Anniversary of the 100th Birthday of Corresponding Member of the Russian Academy of Sciences M. N. Mikheev 相似文献
96.
V. F. Matyuk M. A. Mel’gui D. A. Pinchukov A. L. Lyubarets 《Russian Journal of Nondestructive Testing》2005,41(5):269-276
Results of an experimental study of the anomalous behavior of the residual-magnetization hysteresis of ferromagnetic articles that, under local magnetization and magnetization reversal in a pulsed magnetic field with a variable amplitude, were subjected to heat treatment under different conditions are reported. Parameters of the hysteresis and their dependence on the magnetization and magnetization-reversal conditions, as well as on the magnetic properties of a material, are considered.__________Translated from Defektoskopiya, Vol. 41, No. 5, 2005, pp. 3–13.Original Russian Text Copyright © 2005 by Matyuk, Mel’gui, Pinchukov, Lyubarets.All papers in this issue are devoted to the 100th anniversary of the birth of the late M.N. Mikheev, corresponding member of the Russian Academy of Sciences and one of the founders of magnetic structural analysis. 相似文献
97.
V. H. Novyts’kyi V. P. Havrylyuk D. D. Panasenko M. O. Kal’chuk V. Ya. Khoruzhyi 《Materials Science》2006,42(6):799-807
The positive influence of lead (2.5%) on the original structure of a cast composite of the Fe-Cr-Cu-C-Ti system, its wear
rate, friction coefficient, and the formation of secondary structures is established under the conditions of dry friction
and friction with boundary lubrication.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 42, No. 6, pp. 73–80, November–December, 2006. 相似文献
98.
R. B. Vasil’ev S. G. Dorofeev M. N. Rumyantseva L. I. Ryabova A. M. Gas’kov 《Semiconductors》2006,40(1):104-107
The impedance spectra of nanocrystalline SnO2 ceramics with an average grain size d ranging from 3 to 43 nm were investigated in the frequency range 1–106 Hz at temperatures from 25 to 300°C in a dry oxygen atmosphere. Analysis of the experimental data by the graphoanalytical method made it possible to separate the contributions of grain bulk and grain boundaries to the conductivity. It is shown that the samples investigated can be arbitrarily divided into two groups with respect to the character of their conductivity. For the samples with an average grain size d < 25 nm, the charge transfer processes are almost completely determined by the grain boundaries. In samples with a larger grain size, the contribution of grain bulk to the conductivity is comparable with that of grain boundaries. 相似文献
99.
100.
For a simplest mathematical model of a stock market, the problem of optimal distribution of investments among different securities (stocks, bonds, etc.) is considered. Our results, which are obtained in terms of algorithmic complexity, allow to discuss heuristically the properties of sufficiently complex security portfolios in the conditions of daily changing return rates. All considerations are given in the combinatorial framework and do not use any probabilistic models. 相似文献