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101.
The nonstationary Reynolds equation of the theory of gas lubrication is considered. The existence and uniqueness of a solution to the initial-boundary value problem for this equation are established in the case of sufficiently smooth data. Estimates for the solution are obtained for large bearing numbers. Bibliography: 8 titles. 相似文献
102.
S. K. Gorbatsevich I. A. Kaputskaya S. A. Maskevich S. Yu. Mikhnevich N. D. Strekal’ 《Optics and Spectroscopy》2004,97(2):238-243
The fluorescence of solid solutions of CdSe/ZnS quantum dots and the organic dye DODCI is investigated. It is shown that nonradiative transfer of electronic excitation energy to dye molecules, which with some probability lose their acceptor properties as a result of photoisomerization or photodegradation, is responsible for a significant increase in the fluorescence intensity of a donor. The degree of polarization of the donor fluorescence attains values exceeding 0.5, which is due to the difference in the fluorescence quantum yields of donors with different orientations of the oscillator with respect to the electric vector of an excitation light wave. A numerical simulation of the experimentally observed dependences is performed. 相似文献
103.
Ya. Yu. Nikitin 《Journal of Mathematical Sciences》1992,61(1):1891-1896
The local Chernoff efficiency of the sign and Wilcoxon statistics are derived for the testing of symmetry on the basis of the analysis of the probabilities of large deviations of these statistics under the hypothesis and the alternative.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akademii Nauk SSSR, Vol. 177, pp. 101–107, 1989. 相似文献
104.
Yu. N. Gordeev 《Fluid Dynamics》1995,30(6):870-876
The initial stage of propagation of a vertical hydraulic fracture in an impermeable or low-permeability stratum is considered within the framework of the pseudo-three-dimensional Perkins-Kern model.Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 6, pp. 79–86, November–December, 1995. 相似文献
105.
S. P. Timoshenko Institute of Mechanics, National Academy of Sciences of the Ukraine. Translated from Prikladnaya Mekhanika, Vol. 31, No. 9, pp. 15–23, September, 1995. 相似文献
106.
E.P. Yelsukov Yu.N. Vorobyov T.I. Arbusova I.B. Smolyak 《Journal of magnetism and magnetic materials》1994,130(1-3):44-50
We have measured the concentration dependence of the average magnetic moment per Fe atom
Fe(x) in microcrystalline and amorphous Fe-P alloys obtained over a wide concentration range using electrochemical deposition. The model of local magnetic moments has been used to described
Fe(x). On the basis of this model the effects of phosphorus on the value
Fe are explained in terms of the parameters of the local environment of the Fe atom. 相似文献
107.
108.
S. A. Chernyak O. V. Shekhter N. L. Sergovskaya Yu. S. Tsizin 《Chemistry of Heterocyclic Compounds》1992,28(7):832-834
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 994–996, July, 1992. 相似文献
109.
Three-dimensional inverse scattering of a dielectric target embedded in a lossy half-space 总被引:1,自引:0,他引:1
A modified iterative Born method is applied for three-dimensional inversion of a lossless dielectric target embedded in a lossy half-space. The forward solver employs a modified form of the extended Born method, and the half-space Green's function is computed efficiently via the complex-image technique. Example results are shown, with all scattering data based on a computational model, utilizing a rigorous forward solver distinct from that employed in the inversion. In addition, distinct gridding schemes are used in the forward and inverse solvers. Simple Tikhonov regularization is found to yield adequate results for inversion of noisy data. 相似文献
110.
The dependence of carrier density in silicon quantum wires sheathed with SiO2 on the wire diameter and the position of impurity atoms in respect to the wire center is analyzed theoretically. It is shown that, as the diameter of wires and nanocrystals decreases, the ionization energy of a dopant increases; therefore, the free carrier density decreases, and the screening of the Coulomb attraction becomes ineffective. As a result, the photoluminescence is defined by the radiative recombination of excitons even in the case of heavily doped Si. These conclusions are supported by the data of experimental study of spectral, excitation-power, and temperature dependences of photoluminescence in porous silicon structures fabricated on lightly and heavily doped Si substrates. 相似文献