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931.
932.
D. A. Filippov 《Russian Physics Journal》2004,47(12):1213-1217
A theory of magnetoelectric effect in double-layer ferromagnetic-piezoelectric plate-shape structures is presented. Using the material and motion of continuum equations, an expression for the magnetic coefficient is derived in terms of the parameters characterizing the magnetic and piezoelectric phases. It is shown that in the region of electromagnetic resonance there is a considerable increase in the magnetoelectric coefficient value. A relationship is obtained between the ferromagnetic and piezoelectric thicknesses for which the magnetoelectric coefficient is maximal. The coefficients calculated for the structures based on permendure — plumbum zirconate-titanate are given, and the results of calculations are compared to the experimental data.__________Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 3–6, December 2004. 相似文献
933.
934.
Russian Physics Journal - 相似文献
935.
The problem of dimensionality of time is considered. The space-time curvature is shown to result not only from the presence of the gravitational field but also from a certain other field whose potential is a positive value. 相似文献
936.
Gavrilyuk A. A. Semenov A. L. Gavrilyuk A. V. Mokhovikov A. Yu. Zubritsky S. M. Petrov A. L. 《Russian Physics Journal》2004,47(7):750-755
It has been studied how the conditions of machining and the elastic tensile stresses affect the magnetic properties of amorphous metal wires of composition Fe75Si10B15 produced by drawing from a melt. The magnetic characteristics of wires subjected to both thermal treatment and treatment with a continuous electric current of different magnitude have been investigated. The residual induction of wires is their magnetic parameter most sensitive to the conditions of treatment. The dependences of the residual induction on temperature and on the magnitude of the treating electric current are qualitatively similar. The greatest changes in residual induction are observed in the range of treating electric currents from 0.5 to 0.8 A, which can be associated with the processes of structural relaxation and crystallization occurring in the wires. The run of the dependence of the residual induction on the magnitude of tensile stresses is nonmonotonic in character and is determined by the level of internal hardening stresses of the test wires. 相似文献
937.
P. V. Gorskii 《Russian Physics Journal》2004,47(2):179-182
It is shown that the Kapitza effect in charge-ordered layered crystals can be explained for the case of a parallelism of magnetic field and measuring current when the Landau quantization and its effect on the charge-carrier scattering are considered. There is a linear correlation between the magnetic field and longitudinal resistance under the assumption that the scattering of charge carriers by acoustic phonons is dominant, and the band-to-band transitions are suppressed. The relations for the Kapitza coefficient are derived for different degrees of electron gas degeneracy and different values of interaction resulting in layered charge ordering. 相似文献
938.
939.
G. A. Shulman 《Russian Physics Journal》2004,47(2):115-123
In addition to the solution of the quantum mechanical problem on the motion of a free electron in a magnetic field, given by L. D. Landau in his pioneering work, this quantum mechanical problem is solved in view of the fact that the sum of the components of the free kinetic energy of an electron along two axes is a periodic quantity varying identically within the boundaries of every Landau energy level. This periodicity is a consequence of the quantized motion of an electron in a plane normal to the direction of the external magnetic field. 相似文献
940.
In the present paper, the mathematical expectation and variance of the number of queries in an infinite linear queue are calculated for the Poisson synchronous doubly stochastic stream of incoming queries with two intensity states. 相似文献