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781.
G. V. Loseva S. G. Ovchinnikov É. K. Yakubailik N. I. Kiselev T. A. Gaidalova 《Physics of the Solid State》1998,40(10):1715-1717
A study has been made of the FexV1−x
S solid solutions with 0<x<0.5. For the compounds with x>0.1, x-ray diffraction analysis discloses a V5S8 superstructure. Samples with x>0.1 are magnetically ordered at room temperature. The concentration dependences of resistivity and magnetization exhibit
sharp peaks for x=0.1 and x=0.2, respectively. The main features of the structure and electronic properties have been qualitatively explained in terms
of the three-band exciton-insulator model, and the maxima in resistivity and magnetization are assigned to the formation of
localized magnetic moments with S=1, which become delocalized with increasing x.
Fiz. Tverd. Tela (St. Petersburg) 40, 1890–1893 (October 1998) 相似文献
782.
A near-field scanning optical microscope (NSOM), which we built, is used to investigate 1–5-μm wide stripes with a 10-nm thick
layer—a quantum well — on a GaAs surface. A map of the photoluminescence intensity is obtained synchronously with the topographic
profile of the structures. The measured spatial distribution of the photoluminescence intensity is described satisfactorily
in a model that takes into account carrier diffusion in the layer and the existence of a region with a short carrier lifetime
near the side boundaries of the layer.
Pis’ma Zh. éksp. Teor. Fiz. 63, No. 7, 523–527 (10 April 1996) 相似文献
783.
The structure of the lattice of processes of a finite digraph with entries is investigated. Necessary and sufficient conditions
for the isomorphism of a given lattice to the lattice of processes of a certain digraph are obtained. Bibliography: 5 titles.
Translated by K. V. Shakhbazyan.
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 202, 1992, pp. 135–153. 相似文献
784.
785.
786.
H.G.C. Human N.P. Ferreira C.J. Rademeyer P.K. Faure 《Spectrochimica Acta Part B: Atomic Spectroscopy》1982,37(7):593-602
A method and computer program were developed for calculating the temperature of any part of a graphite furnace tube at any instant of time after onset of the heating cycle. Results for tubes of the Massman design show large differences in spatial temperature distributions during and at the end of the heating cycle when equilibrium is reached. When constant current is applied to contoured tubes, greater heating rates at the tube centres are obtained than with standard tubes. 相似文献
787.
We study regimes of total reflection of a plane wave to the diffraction lobe in the case where the wave is incident on a corrugated
metal surface or a corrugated interface of two dielectric media. The purpose is to analyze the influence of both the corrugation
shape and losses in the medium on the characteristics of the regimes of total reflection to the diffraction lobe. We consider
a number of corrugation profiles differing from the sinusoid by the resonance-region width and the presence of additional
elements, namely, (i) the profiles having pair resonance regions with scale of the order of the wavelength, for which qualitatively
new diffraction regimes compared with those observed for the sinusoidal interface can be realized due to interaction of waves,
and (ii) the profiles comprising small-scale deviations, which can be a model of actual gratings. To study the influence of
losses in the problem of scattering from a corrugated interface of dielectrics, the dielectric permittivity is assumed complex.
We compare the obtained results with data for a sinusoidal profile and loss-free media.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 5, pp. 391–405, May 2006. 相似文献
788.
789.
790.
A method for estimating the systematic uncertainty associated with radon in the SAGE experiment1) aimed at observing the solar-neutrino flux is described. For the gallium target used in this experiment, the systematic uncertainty in the measured neutrino-capture rate of 75 SNU2) is below 0.3 SNU. 相似文献