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811.
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
812.
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
813.
I. M. Shmyt’ko A. N. Izotov N. S. Afonikova S. Vieira G. Rubio 《Physics of the Solid State》1998,40(4):687-690
The formation of polytypic modifications is observed in dislocation-free silicon single crystals under directional plastic
deformation. It is shown that the deformation-stimulated phase appears on the surface of the sample in the form of small grains
ranging from several hundred to several thousand angstroms in size. A twin structure in the individual grains is observed.
Fiz. Tverd. Tela (St. Petersburg) 40, 746–749 (April 1998) 相似文献
814.
We propose a method for deriving duality relations for two-dimensional inhomogeneous Z(N)-symmetric models on a finite square lattice wound around a torus. The method is used to obtain duality relations for the
vector Potts model, the Berezinskii-Villain Z(N)-model, the Ashkin-Teller model, and the 8-vertex model on a lattice obliquely wound around a torus, as well as an exact
relation linking the partition functions of the latter two models.
Zh. éksp. Teor. Fiz. 113, 240–260 (January 1998) 相似文献
815.
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
816.
S. A. Kazantsev N. M. Firstova L. K. Kashapova A. V. Bulatov A. G. Petrashen' 《Russian Physics Journal》1998,41(12):1258-1262
Polarization data are given for three whiskers recorded with the large solar vacuum telescope at the Baikal Observatory, Institute
of Solar-Terrestrial Physics, Russian Academy of Sciences. The observed degree of polarization varies from 2 to 13%. The direction
of the polarization plane for the mediumintensity whisker was tangential, while that for the weakest one was radial. The brightest
whisker had the polarization plane direction close to radial at the center of the line but tangential at the flanks. It is
assumed that the polarization is due to impact excitation of a hydrogen-atom ensemble in the solar chromosphere by an electron
beam, and estimates are made of the beam energy.
St. Petersburg Fine Mechanics and Optics Institute, St. Petersburg. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii,
Fizika, Vol. 41, No. 12, pp. 85–89, December 1998. 相似文献
817.
Experiments on permanent lattice-defect formation induced by electronic excitation of rare-gas solids are presented. The creation
of triplet excitons Γ(3/2) is found to be the primary process, followed by the exciton self-trapping. Probable models of defect
formation are discussed.
Fiz. Tverd. Tela (St. Petersburg) 40, 903–906 (May 1998)
Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor. 相似文献
818.
The dynamics of defects with linear dimensions from ≈1 to ≈100 nm on a Au surface under load have been studied by means of
tunnelling microscopy. It is found that the origin, growth, and resorption of the defects is caused by displacements of bands
of material from 5 to 50 nm wide, parallel to the {111} slip planes. The defects can be separated into two groups: nonsteady-state
defects, whose lifetime does not exceed 15 min, while the depth is ⩽20 nm, and quasi-steady-state defects, with a lifetime
three orders of magnitude greater than the first. It is assumed that the nonsteady-state defects are formed when the ensemble
of dislocations is being reconstructed, while the quasi-steady-state defects are formed at the instant of formation of dislocation
substructures during the creep of the loaded metal.
Fiz. Tverd. Tela (St. Petersburg) 40, 2180–2183 (December 1998) 相似文献
819.
K. N. Ponomaryov 《Algebra and Logic》1998,37(6):380-390
The structure of scalar fields for a directly indecomposable finite-dimensional algebra treated as a ring is studied. Scalar
fields are assumed similar if their action on a ring is identical modulo an annihilator. The criterion for a class of maximal
scalar fields to be unique under a similitude relation is established.
Supported by RFFR grant No. 96-01-01675, and by RF State Committee of Higher Education.
Translated fromAlgebra i Logika, Vol. 37, No. 6, pp. 667–686, November–December, 1998. 相似文献
820.
The magnetic phase diagrams of a two-sublattice ferrimagnet with a magnetically unstable subsystem are calculated taking account
of the susceptibility. Analytic expressions are obtained for the phase-transition fields and critical values of the parameters
of the ferrimagnet. The evolution of the magnetic phase diagrams as the susceptibility of the unstable sublattice increases
is analyzed. 相似文献