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1.
Influence of the skin effect on the absorption of electromagnetic radiation by a fine metal particle
The cross section of absorption of electromagnetic radiation by a fine spherical metal particle is calculated. The influence of the skin effect on the absorption cross-section is estimated for an arbitrary ratio between the free path and size of the particle. The results of this work are compared with those obtained earlier in the framework of classical electrodynamics. It is shown that taking into account the kinetic effects modifies essentially the known data for the skin effect in a spherical particle. 相似文献
2.
S. A. Moiseev 《Optics and Spectroscopy》2003,94(5):788-796
A new variant of realization of quantum memory based on the use of a photon echo in an optically dense three-level gaseous medium is proposed. The use of a long-lived highly excited optical level as a storage of quantum information is the characteristic feature of the scheme proposed. This scheme of quantum memory is distinguished by reduced optical noises owing to the possibility of realizing temporal, spectral, and spatial selection of weak quantum radiation relative to the accompanying laser pulsed fields. 相似文献
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I. I. Antakov M. A. Moiseev E. V. Sokolov E. V. Zasypkin 《International Journal of Infrared and Millimeter Waves》1994,15(5):873-887
Using self-consistent field theory, the interaction of electron flow with HF fields in a gyroklystron has been analized. Optimal parameters of its output cavity corresponding to the maximum efficiency have been found. Experimental study of dependence of the efficiency on Q-factor and length of the output cavity has been carried out. The results of simulation are in good qualitative agreement with experimental data. 相似文献
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Dmitry V. Moiseev Vera A. Morugova Andrey S. Shavirin Victor A. Dodonov 《Journal of organometallic chemistry》2004,689(4):731-737
Tetraphenylantimony(V) carboxylates have been used in the palladium-catalyzed C-phenylation reaction of methyl acrylate in the presence of (PhCO2)2 or t-BuOOH under mild conditions (50 °C). The peroxides promote a cascade participation of the organoantimony compound and result in the transfer of three phenyl groups. Organoantimony intermediates have been isolated from the reaction. 相似文献
7.
A consistent quantum theory of a two-pulse pump-probe experiment in the femto-and picosecond spectroscopy of diatomic molecules is developed. The theory aims at the use of weak quantum femtosecond light pulses to excite molecular coherence. It is suggested that the experiment be realized using a double-frequency excitation scheme that is feasible for Na2 molecules. On the basis of the theory developed, the luminescence signals are calculated at different temperatures and different optical densities of the medium for the time range from 100 fs to ~ 100 ps. The results obtained show the presence of a strong dependence of the time and frequency spectra of a luminescence signal on the optical density of the medium at temperatures from 50 to 300 K. The proposed approach makes it possible to use the quantum coherence properties of optically dense media for more detailed study of the vibronic dynamics of diatomic molecules, in particular, detection of weak optical transitions. 相似文献
8.
N. A. Zavolsky V. E. Zapevalov M. A. Moiseev 《Radiophysics and Quantum Electronics》2006,49(2):108-119
We study theoretically the influence of the spread of initial energies and velocities in the electron beam on the starting
conditions and efficiency of a gyrotron. We compare various analytical and numerical models and the results of experimental
studies of gyrotrons in which the interaction takes place at the first and second harmonics of the cyclotron frequency. The
aftercavity interaction of the electron beam with the high-frequency field in the output waveguide transition is taken into
account. The influence of the energy spread on the recuperation efficiency is estimated. Permissible spreads of the initial
energies and electron velocities are determined.
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Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 2, pp. 121–133, February 2006. 相似文献
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Stolyarov I. P. Gaugash Yu. V. Kryukova G. N. Kochubei D. I. Vargaftik M. N. Moiseev I. I. 《Russian Chemical Bulletin》2004,53(6):1194-1199
The reduction of palladium(ii) carboxylates Pd3(OCOR)6 (R = Me, Et, CHMe2, CMe3) with hydrogen in alcohol solutions containing 1,10-phenanthroline (phen) and subsequent oxidation with oxygen gave new palladium nanoclusters, mainly particles with a nearly spherical metal core and an average size of 18 . Based on elemental analysis, NMR, X-ray photoelectron spectroscopy, and EXAFS, nanoclusters were described by the idealized formula Pd147phen32O60(OCOR)30. The specimens contained up to 25% smaller 55-atomic Pd clusters with a 10 metal core. New nanoclusters catalyze hydrogenation of alkynes and alkenes, reduction of nitriles with formic acid, oxidation of aliphatic and benzylic alcohols, oxidative esterification of ethylene and propylene, and disproportionation of benzyl alcohol into toluene and benzaldehyde. 相似文献