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271.
D. N. Karimov E. A. Krivandina Z. I. Zhmurova B. P. Sobolev V. A. Bezhanov S. P. Chernov G. M. Shapochkin 《Crystallography Reports》2006,51(6):1009-1015
Crystalline materials that are transparent in the vacuum UV spectral region and currently used have been reviewed. Transmission of crystals of solid solutions with the fluorite structure Ca1?x R xF2+x (R = Sc, Y, La, Yb, Lu) in the UV and vacuum UV spectral regions has been investigated. It is shown that application of different methods of purification of fluorides from some impurities can significantly improve the optical quality of fluoride multicomponent crystals in the short-wavelength spectral region. 相似文献
272.
273.
O. I. Gyrdasova V. N. Krasil’nikov I. G. Grigorov G. V. Bazuev 《Russian Journal of Inorganic Chemistry》2006,51(6):949-955
The effect of ethylene glycol (EG) on the formation of whiskers and fibers of complex oxides with the general formula MCo2O4 upon the thermolysis of M1/3Co2/3C2O4 (M = Zn, Mn) oxalates has been studied. New compounds (solvates) are formed when powdered oxalates are heated with EG. In the solvates, EG molecules substitute for water molecules according to the reaction M1/3Co2/3C2O4 · 2H2O + HOCH2CH2OH = M1/3Co2/3C2O4(HOCH2CH2OH) + 2H2O. The solvates have been characterized using X-ray powder diffraction, microscopy, IR spectroscopy, thermogravimetry, and chemical analysis. The shape, structure, and particle size of the thermolysis products of EG-modified oxalates have been determined using scanning electron microscopy. 相似文献
274.
275.
276.
In this paper the performances of inhomogeneous dielectric slabs as solar light collectors for both illumination and solar energy applications are analysed. 相似文献
277.
Calculations are performed, using a basis of two-center functions described previously, for excited states of the following three-and four-electron compounds: H2
–, He2
+, He2, Li2
+2. High efficiency is demonstrated for the frozen ionic core approximation and the nonorthogonal orbital method in such calculations. For four-electron systems the practical feasibility of the frozen hybrid core approximation is demonstrated.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 53–56, August, 1987. 相似文献
278.
V. Yu. Karaev E. M. Meshkov G. N. Balandina E. M. Zuikova V. Yu. Gol'dblat V. I. Titov 《Radiophysics and Quantum Electronics》2005,48(8):587-598
We present the results of data processing of the field experiment devoted to a study of a microwave signal backscattered by
a rough water surface and compare them with the theoretical estimates. The measurements were conducted sequentially using
a radar with parabolic and knife-beam antennas. The radar was mounted on the Molitovsky bridge at a height of 40 m across
the Oka river in Nizhny Novgorod, Russia. For the radar with knife-shaped antenna pattern, we examined the reflected-signal
power and the shift and width of the Doppler spectrum as functions of the azimuthal angle for the nadir sounding. For the
parabolic antenna, we studied the reflected-signal power as a function of the incidence angle. Comparison with the experimental
data shows that the developed theoretical model of a Doppler spectrum is in good agreement with the observations.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 48, No. 8, pp. 661–673, August 2005. 相似文献
279.
Bogdanovskaya V. A. Grinberg V. A. Krishtalik L. I. Kuznetsov A. M. Pleskov Yu. V. Skundin A. M. Tarasevich M. R. Tsyrlina G. A. 《Russian Journal of Electrochemistry》2003,39(4):441-444
Russian Journal of Electrochemistry - 相似文献
280.
We describe in detail fundamental properties of continuity modules of various orders in the spaces L
p of functions defined on a finite segment. We establish some general estimates of seminorms in terms of continuity modules with the best known constants. An example of application of these results to the best approximations is considered. Bibliography: 32 titles. 相似文献