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1.
V. V. Lozhkarev S. G. Garanin R. R. Gerke V. N. Ginzburg E. V. Katin A. V. Kirsanov G. A. Luchinin A. N. Mal’shakov M. A. Mart’yanov O. V. Palashov A. K. Poteomkin N. N. Rukavishnikov A. M. Sergeev S. A. Sukharev G. I. Freidman E. A. Khazanov A. V. Charukhchev A. A. Shaikin I. V. Yakovlev 《JETP Letters》2005,82(4):178-180
In experiments on the parametrical amplification of femtosecond pulses in wide-aperture DKDP crystals, a power of more than 100 TW has been reached, which is much higher than the record level achieved in such lasers. The energy efficiency obtained for the parametric amplifier is equal to 27%. The energy of a 72-fs pulse is equal to 10 J. 相似文献
2.
The electrodynamic properties of coaxial two-dimensional Bragg resonators with two-dimensional distributed feedback are analyzed. These resonators are made of coaxial waveguide sections with doubly periodic corrugation, which provides coupling and mutual scattering of four partial waves. Two of them propagate along the waveguide, while the other two propagate in the transverse (azimuthal) direction. It is shown that the high azimuthal index selectivity of two-dimensional Bragg resonators may be related to a qualitative difference in topology of the dispersion characteristics of azimuth-symmetric and asymmetric normal waves propagating in infinite waveguides of such a geometry. For the finite-length systems used as two-dimensional Bragg resonators, the eigenmode spectrum is found for two types of boundary conditions that correspond to the limiting cases of perfectly matched (open) systems and, conversely, of systems closed for the extraction of transverse electromagnetic fluxes. Perimeter-to-length ratios of the resonator at which the Q factor of the fundamental azimuth-symmetric mode is greater than those of the other modes are determined. The applicability domain of the geometrical approach, which was earlier applied to two-dimensional Bragg resonators, is discussed. 相似文献
3.
On the basis of the intermolecular potentials data structural phase transitions in polymer crystals (polyethylene) are described. By using the meanfield approximation, the theories of premelting transitions for paraffin crystals and conformational melting of polyethylene crystals were developed. The dependence of temperatures of such transitions upon chain length was calculated and rather good agreement with experimental data was shown.Dedicated to Prof. Dr. W. Pechhold on the occasion of his 60th birthday 相似文献
4.
V. A. Ginzburg 《Functional Analysis and Its Applications》1992,26(1):51-52
The Institute of the Earth Physics, Academy of Sciences of the USSR. Translated from Funktsional'nyi Analiz i Ego Prilozheniya, Vol. 26, No. 1, pp. 64–66, January–March, 1992. 相似文献
5.
Ginzburg B. M. Smirnov A. S. Filatov S. K. Shibaev L. A. Melenevskaya E. Yu. Novoselova A. V. Shepelevskii A. A. 《Russian Journal of Applied Chemistry》2003,76(3):457-459
The structure of aggregates of fullerene C6
0 introduced into films of radical polymethyl methacrylate in the stage of solution preparation was studied by wide-angle X-ray diffraction. 相似文献
6.
One considers the class
G
of holomorphic functions in a domain G, whose values are contractions in a separable Hilbert space. It is proved that if T(·)
G
, T(z0) is a weak contraction, its singular part Ts(z0) is complete, and the increments T(z)–T(z0) are not too large (for example, finite-dimensional), then the operator Ts(z0) is complete for almost all zG. If, however, T(z0) is, in addition, completely nonunitary and satisfies definite smoothness conditions, then in the nontrivial case the spectrum [z] of the contraction Ts(z) (zG) is a thin set: The proof of the mentioned results is based on the investigation of the formulas obtained in the paper, connecting the characteristic functions of the contractions T(z) for different values of zG.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 157, pp. 30–44, 1987. 相似文献
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B. M. Ginzburg D. G. Tochil’nikov A. A. Shepelevskii A. M. Leksovskii Sh. Tuichiev 《Russian Journal of Applied Chemistry》2006,79(9):1518-1521
The effect of fullerene black introduced (after extraction of light fullerenes from the black with toluene) into polytetrafluoroethylene F-4 on its wear resistance and antifriction properties in sliding over steel at contact pressures in the range 0.2–2.0 MPa was studied. 相似文献