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211.
The low-temperature reaction of magnesium with fluorobenzene has been investigated. Joint condensation of magnesium and fluorobenzene vapours at low temperatures quantitatively gave phenylmagnesium fluoride in one stage. 相似文献
212.
213.
Parametric interactions in nonlinear crystals represent a powerful tool in the optical manipulation of information, both in the classical and the quantum regime. Here, we analyze in detail classical and quantum aspects of three-and five-mode parametric interactions in x(2) nonlinear crystals. The equations of motion are explicitly derived and then solved within the parametric approximation. We describe several applications, including holography, all-optical gates, generation of entanglement, and telecloning. Experimental results on the photon distributions and correlations of the generated beams are also reported and discussed. 相似文献
214.
A. A. Berezhnoy F. L. Vladimirov I. Yu. Grodetskii Yu. L. Korzinin V. I. Sukhanov 《Optics and Spectroscopy》2002,93(5):777-780
The possibility of usage of the spontaneous electrooptical (EO) effect in strontium barium niobate (SBN) crystals for the creation of controlled electroholographic elements is studied. It is found that unipolar EO properties of these crystals with respect to switching their spontaneous polarization make it possible to devise field-controlled holographic elements with reversible energy-independent memory for spatial position of an optical beam. 相似文献
215.
G. P. Gurinovich 《Journal of Applied Spectroscopy》1991,54(3):243-249
216.
A. S. Kosmodamianskii V. I. Storozhev V. A. Shpak 《Journal of Mathematical Sciences》1991,57(1):2918-2922
A solution is constructed for an orthotropic layer with free plane faces, that corresponds to the plane elastic waves symmetric over the thickness. The dynamical reconstruction of the normal wave spectrum during rotation of the wave vector from one to another elastically equivalent direction is investigated on the basis of a numerical analysis of the dispersion equation.Translated from Teoreticheskaya i Prikladnaya Mekhanika, No. 19, pp. 116–121, 1988. 相似文献
217.
Defect formation and annealing processes in fullerene C60 at T = (4000–6000) K are studied using molecular dynamics with a tight-binding potential. The cluster lifetime until fragmentation, which proceeds, as a rule, through the loss of a C2 dimer, has been found as a function of temperature. The activation energy and the frequency factor in the Arrhenius equation for the fragmentation rate have been found to be E a = (9.2 ± 0.4) eV and A = (8 ± 1) × 1019s?1. It is shown that fragmentation can occur already after the C60 cluster loses its spherical shape. This fact must be taken into account in theoretical calculations of E a. 相似文献
218.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 6, pp. 965–969, June, 1991. 相似文献
219.
E. G. Ryabova 《Computational Mathematics and Modeling》1992,3(1):30-35
Translated from Vychislitel'nye Kompleksy i Modelirovanie Slozhnykh Sistem, pp. 98–106, Moscow State University, 1989. 相似文献
220.
I.L. Lyubchanskii N.N. Dadoenkova M.I. Lyubchanskii E.A. Shapovalov A.E. Zabolotin K.Y. Guslienko T. Rasing 《Applied physics. B, Lasers and optics》2002,74(7-8):711-714
Nonlinear (at the second-harmonic frequency of the incident light) optical reflection by two-dimensional magnetic superstructures
is theoretically studied. A square lattice of magnetic dots and a hexagonal lattice of magnetic bubbles (cylindrical magnetic
domains) are considered. Because the periods of these structures are comparable with the wavelengths of the fundamental and
the second-harmonic radiation, it would be possible to observe diffraction at the second-harmonic frequency. A polarization
analysis of nonlinearly diffracted radiation is performed and the numbers of observable diffraction orders for the above structures
are estimated.
Received: 10 January 2002 / Published online: 11 June 2002 相似文献