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931.
We obtain an exact solution of the problem of the stress-strain state of an elastic piezoelectric half-space acted on by a
rigid elliptic die with a flat base. The axis of symmetry of the body coincides with the direction of the field of preliminary
polarization of the body. The solution is confined to the case of translational displacement of the die. We determine the
quantities that characterize the mechanical and electric fields that arise in the region of contact of the die with the half-space.
Bibliography: 7 titles.
Translated fromTeoreticheskaya i Prikladnaya Mekhanika, No. 28, 1998, pp. 40–52. 相似文献
932.
Yu. G. Abov D. S. Denisov N. O. Elyutin S. K. Matveev Yu. I. Smirnov A. O. Éidlin F. S. Dzheparov D. V. L’vov 《Journal of Experimental and Theoretical Physics》1998,87(6):1195-1200
The asymptotic behavior of the spectra for large values of the scattering vector for the case of elastic multiple small-angle
neutron scattering (SANS) is investigated theoretically and experimentally. An expansion of the spectrum in terms of the reciprocal
of the magnitude of the momentum transfer is obtained taking account of the influence of the instrumental line. It is shown
that, to within some factor, the leading term of the expansion is identical to the differential single-scattering cross section
averaged over a statistical ensemble of particles; several subsequent terms in the expansion are calculated and the range
of applicability of the resulting expressions is determined. The asymptotic behavior of the multiple SANS spectrum is measured,
using a two-crystal neutron spectrometer, for samples of an HTSC ceramic, the alloy Fe-Ni, and Al powder. The agreement between
the experimental results and the theoretical predictions is analyzed.
Zh. éksp. Teor. Fiz. 114, 2194–2203 (December 1998) 相似文献
933.
A. V. Kudinov Yu. G. Kusraev B. P. Zakharchenya V. N. Yakimovich 《Physics of the Solid State》1998,40(5):823-825
Polarized photoluminescence of Cd1−x
MnxTe crystals in a weak magnetic field has been studied in Faraday and Voigt geometries. A simple method is proposed to determine
the exciton mobility edge and excitonic magnetic-polaron energy. “Forbidden” polarization components of the recombination
radiation have been experimentally detected. It has been established that the moments of magnetic polarons are oriented predominantly
along the {111} axes.
Fiz. Tverd. Tela (St. Petersburg) 40, 894–896 (May 1998) 相似文献
934.
Time-resolved photoluminescence from porous silicon coated with a diamondlike carbon film is investigated. The intensity of
the photoluminescence from the carbon film is obserd to increase after deposition, and there is an accompanying change in
the intensity and a shortwavelength shift of the photoluminescence band of porous silicon that depends on the porosity of
its original layers. These changes are explained by the formation of carbon nanoclusters on the surface of the silicon filaments.
Zh. Tekh. Fiz. 68, 83–87 (April 1998) 相似文献
935.
O. Ya. Butkovskii Yu. A. Kravtsov E. D. Surovyatkina 《Journal of Experimental and Theoretical Physics》1998,86(1):206-212
The structure of the attraction zones of the final states associated with dynamical period doubling bifurcations is investigated.
It is found that on the “initial value—transition rate” plane the attraction zones of the two possible final states alternate
with each other and that a subdivision of the attraction regions occurs with a decrease in the transition rate. It is shown
that the boundaries of the attraction zones are smeared out because of the effect of noise and in this situation the fine
structure of the attraction zones is destroyed. As analytical and numerical calculations have shown, the critical value of
the noise variance, corresponding to the boundary between the dynamical (or predictable) and stochastic (or unpredictable)
modes, has a power-law dependence on the transition rate with a typical exponent value of one. The existence of “noise” invariants
is also observed: the integrated (over all initial values) probability of achieving the final state is invariant with respect
to the noise level.
Zh. éksp. Teor. Fiz. 113, 369–380 (January 1998) 相似文献
936.
937.
938.
Studies of the influence of plastic deformation and the straining temperature on the temperature dependence of the stresses
developed in titanium nickelide shape memory alloys are described.
Zh. Tekh. Fiz. 68, 141–142 (July 1998) 相似文献
939.
940.
Yu. I. Bespyatykh V. Vasilevskii É. G. Lokk V. D. Kharitonov 《Physics of the Solid State》1998,40(6):975-981
Specific models of domain walls are used to investigate conditions for the single-domain state and quasi-single-domain states
in structures with magnetic materials having a quality factor higher than one. It is shown that the critical thickness of
the magnetic film in a tangentially magnetized system decreases monotonically as the magnetizing field increases from zero
to the transition from the collinear to the homogeneous angular phase and then increases monotonically with increasing external
field. In a thin isolated magnetic film, the size of the domains increases exponentially with decreasing thickness. This dependence
is logarithmic near the transition to the single-domain state for a film coated on two sides and obeys a power law for a film
coated on one side. The establishment of a single-domain state and characteristic features in the asymptotic behavior of the
domain structure in magnetic films with and without coatings can be attributed to differences in the asymptotic behavior of
the field of a single domain wall.
Fiz. Tverd. Tela (St. Petersburg) 40, 1068–1074 (June 1998) 相似文献