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991.
E. E. Sirotkina A. I. Khlebnikov N. A. Domina A. V. Domin 《Russian Physics Journal》2004,47(11):1134-1138
Intensities of principal diffraction maxima for a phase reflection diffraction grating with a rectangular groove profile were calculated by the Fresnel method, using a special algorithm. The procedure under consideration enables us to perform high-efficiency calculations of diffracted-beam characteristics and can be used extensively to optimize diffraction-grating parameters.__________This revised version was published online in May 2005 with a correction on affiliation.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 38–41, November 2004. 相似文献
992.
Two nonstationary cosmological models with rotation are constructed for the Bianchi II metric within the Einstein gravitation theory. The first model is filled with a co-moving perfect liquid and radiation field and is characterized by nonzero expansion, rotation, and acceleration. A perfect liquid which is not co-moving with a reference system is a source of gravitation for the second model. The second model corresponds to nonzero rotations and accelerations. 相似文献
993.
E. V. Glukhova 《Russian Physics Journal》2004,47(2):154-159
In the present paper, the main probabilistic characteristics (the mathematical expectation, variance, and correlation function) of the amount of harmful substances in anthropogenic formations are calculated under the stationary conditions when the stream of these substances is a recurrent stream of events. 相似文献
994.
995.
996.
997.
M. A. Elkin B. S. Ishkhanov I. M. Kapitonov E. I. Lileeva E. V. Shirokov 《Physics of Atomic Nuclei》2004,67(4):653-661
An isotopic effect in the widths of giant dipole resonances is established on the basis of an analysis of the latest systematics of photoabsorption cross sections for nuclei containing 12 to 65 nucleons. This effect arises owing to isospin splitting of a giant resonance and is enhanced by its configuration splitting. 相似文献
998.
G. E. Malashkevich V. N. Sigaev G. I. Semkova B. Champagnon 《Physics of the Solid State》2004,46(3):552-556
The spectral-luminescent properties of silica gel glasses coactivated by Ce4+ and Eu3+ ions are investigated. The structure of the glasses is studied using x-ray powder diffraction and small-angle neutron scattering. The inference is drawn that Ce4+-Eu3+ centers with high-symmetry Eu(III) oxo complexes, which are formed in the glasses, have nanocrystalline nature. These centers are characterized by a weak vibronic interaction of Eu3+ ions with the matrix. The size of nanocrystallites formed under the synthesis conditions and at coactivator concentrations used is approximately equal to 10 nm. 相似文献
999.
M. E. Kompan V. P. Kuznetsov V. V. Rozanov A. V. Yakubovich 《Physics of the Solid State》2004,46(6):1110-1112
The size of an ionistor capacitor structure is found to change during its charging and discharging. The specific feature of this effect that distinguishes it from other known effects of changing sizes under electric and magnetic fields (the piezoelectric effect and striction) is the complete hysteresis; i.e., the size reached under the exposure remains unchanged after the field is turned off. 相似文献
1000.
The ion transverse velocity distribution functions and the fraction η of ions heated above a certain energy W
1 are calculated as applied to the ion cyclotron resonance heating method of isotope separation. It is assumed that the longitudinal
ion velocity distribution in a plasma source is nonequilibrium. Under high heating temperatures, the averaged ion transverse
velocity distribution becomes essentially nonequilibrium and exhibits two maxima. The ion heating efficiency η is calculated
for W
1=40 eV and various values of the parameter p=λ/L, where λ is the wavelength of the electric field of an antenna and L is the heating zone extension. The relative contributions of the time-of-flight and Doppler broadenings are evaluated. 相似文献