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1.
It is shown that the nonstable character of nonlinear interaction of a system of waves similar to that resulting from double stimulated Brillouin scattering is retained upon the oblique incidence of a powerful electromagnetic wave on a layer of supercritical plasma. In this case we have nonlinear back reflection from a layer of supercritical plasma. The threshold intensity of the pump wave is greater than that in the case of subcritical plasma for TE polarization waves but can markedly decrease for waves polarized in the incidence plane. Instability is possible only for a layer of finite thickness.Radiophysical Research Institute, Nizhny Novgorod. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 38, Nos. 3–4, pp. 298–303, March–April, 1995.  相似文献   
2.
We study the stationary solution of an unstable system of interacting inhomogeneous electromagnetic waves and an acoustic wave. It is shown that the instability of this system is of hard type and the threshold of its vanishing is smaller than the excitation threshold. When the amplitude of the incident wave exceeds the threshold value there occurs interaction with partial nonlinear layer transmission, which is changed by large reflection for a large wave amplitude. In this case, the total reflection in the direction opposite to the incident wave and in the specular direction can be greater than in the absence of interaction. A parameter region in which the backward reflection dominates the specular reflection is shown. Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 40, No. 9, pp. 1132–1143, September, 1997.  相似文献   
3.
The problem of scattering of a Rayleigh wave by a chain of identical closely spaced monopole-dipole resonators with friction is considered. The values of resonator parameters that provide the rejection of the Rayleigh wave are found. The conditions under which the Rayleigh wave is much more efficiently reflected by the dipole resonators than by the monopole ones are determined.  相似文献   
4.
Translated from Matematicheskie Zametki, Vol. 54, No. 1, pp. 52–56, July, 1993.  相似文献   
5.
A new method is proposed for determining the magnetic characteristics (magnitude and sign of the exchange interaction energy and the average size of clusters of magnetic ions) of dilute solid solutions of semimagnetic semiconductors at low temperatures based on oscillation measurements. The method makes it possible to find the magnetic characteristics of the indicated systems at temperatures between the point of the transition into the spin glass state and the temperature corresponding to the characteristic binding energy of magnetic atoms in clusters, for which standard methods based on the measurement of the magnetic susceptibility are not effective. The method is used to study the character of the exchange interaction in the system of solid solutions Hg1–xMnxSe as a function of their composition as well as under conditions of hydrostatic compression. To this end the oscillations of the magnetoresistance (Shubnikov-de Haas (SH) effect) in single-crystalline samples of Hg1–xMnxSe in the region of compositions 0.001 x 0.23 in magnetic fields H up to 65 kOe at temperatures T = (0.4–20) K and pressures up to 16 kbar were studied.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 29–39, November, 1989.  相似文献   
6.
Conclusions Ammonium phosphonium salts are formed when tertiary phosphines are reacted with benzalaniline in the presence of dry HCl.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 719–720, March, 1984.  相似文献   
7.
Basic characteristics (efficiency, selectivity, non-equilibrium) of capillary columns with a super-thick layer of stationary liquid phase are investigated. In contrast to traditionally used capillary columns with standard stationary phase thickness of 0.1-0.5 um, some new variables are now established. Firstly, the values of relative retention depend on carrier gas linear velocity. Secondly, the asymmetry of chromatographic peaks increased in accordance with the increase in carrier gas velocity. Thirdly, it was theoretically and experimentally shown that dependence of the height equivalent to a theoretical plate (HETP) on carrier gas velocity is linear. The above noted variables are evidences that the new type of GC is realized under these conditions. The use of capillary columns with super-thick layer of stationary liquid phase is practical when the following problems have to be solved: (1) Separation of highly volatile substances; (2) Preliminary concentration of trace compounds from strong diluted samples; (3) Improvements in measurement and accuracy due to the advantages of splitless injection into wide bore columns with super-thick films. Solutions to some analytical tasks while using super-thick stationary liquid phase are shown: (1) Large volume injection into capillary column with sample transfer speed up to 100 microL min(-1); (2) Isothermal splitless injection; (3) Separation of low boiling compounds; (4) Separation of polar substances (alcohols).  相似文献   
8.
An experimental investigation was made of metal-insulator-semiconductor transistors with thick insulator and long channel and made of single-crystal p-type InSb (78° K). An empirical relation was obtained for the output drain conductance in the case of carrier degeneracy in the n-type channel. The parameters of the InSb surface after etching were determined.Translated from Izvestiya Uchebnykh Zavedenii, Fizika, No. 4, pp. 84–88, April, 1980.  相似文献   
9.
The reaction C C has been studied at 36 GeV/c. A clear signal for the decaya 2 (1320) · is observed in the mass spectrum. The measured ratio of branchings is BR (a 2 )/BR(a 2 );(3.4±0.8±0.5)·10–2.  相似文献   
10.
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