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Taking into account the effect of cubic nonlinearity on the process of second harmonic generation by soliton-like femtosecond pulses results in a hysteresis dependence of the generation efficiency, the pulse durations, and the mismatch of the wave numbers of the interacting waves on their total energy. Color solitons with earlier unknown shapes are formed at a high efficiency of the frequency conversion. Varying the phase mismatch makes it possible to “switch” the soliton duration and the conversion efficiency without a change in the total energy of the waves or the soliton shape. It is emphasized that the soliton corresponding to the middle branch of the hysteresis dependence is stable against small perturbations. It is significant that the soliton shape remains unchanged in the considered range of energies. 相似文献
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V. N. Volynets D. I. Slovetskii A. Ya. Strochkov V. N. Trofimov 《Journal of Applied Spectroscopy》1991,54(6):613-619
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 6, pp. 1004–1010, June, 1991. 相似文献
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L. A. Oparina O. V. Vysotskaya A. V. Stepanov I. V. Rodionova G. F. Myachina N. K. Gusarova B. A. Trofimov 《Russian Journal of Organic Chemistry》2008,44(1):120-123
2-Hydroxymethylfuran reacted with acetylene in superbasic catalytic systems MOH-DMSO (M = Na, K) under mild temperature conditions (75–85°C, 1–2 h), yielding 80% of 2-vinyloxymethylfuran. The product, as well as acetaldehyde acetals derived therefrom, turned out to be promising as modifiers for electrolyte in lithium-sulfur rechargeable batteries. 相似文献
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Ivanova N. I. Gusarova N. K. Reutskaya A. M. Shaikhutdinova S. I. Arbuzova S. N. Trofimov B. A. 《Russian Journal of General Chemistry》2003,73(6):877-879
Symmetrical and unsymmetrical tertiary phosphine oxides containing benzyl and 5-chloro-2-thienyl radicals stereoselectively react with benzaldehyde in the sodium amide-THF system to form the E isomers of 1-organyl-2-phenylethene and diorganylphosphinic acids in high yields. Triethyl, tris(2-phenyl- ethyl)-, and tris[(4-methoxyphenyl)methyl]phosphine oxides under the above-mentioned conditions do not react with benzaldehyde. 相似文献
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V. B. Kobychev N. M. Vitkovskaya I. L. Zaitseva B. A. Trofimov 《Journal of Structural Chemistry》2004,45(6):940-944
The profiles of reactions leading to pyrrole anion N-adducts with CO2 and CS2 have been studied by the ab initio (RHF/6-31+G*, MP2/6-31+G*) and density functional (B3LYP/6-31+G*) methods. Addition of the pyrrole anion to the carbon disulfide molecule is accompanied by the appearance of a minimum corresponding to a pre-reaction complex. The transformation of the complex to the N-pyrrolyldithiocarboxylate anion occurs via a low activation barrier, which is due to repolarization of the C=S bonds. The profile of the reaction leading to the pyrrole anion N-adduct with CO2 does not contain any intermediate stationary points throughout the whole route from reagents to products.Original Russian Text Copyright © 2004 by V. B. Kobychev, N. M. Vitkovskaya, I. L. Zaitseva, and B. A. Trofimov__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 990–993, November–December, 2004. 相似文献
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