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101.
V. V. Gritsenko O. A. D'yachenko A. I. Kotov L. I. Buravov M. Mizuno 《Russian Journal of Coordination Chemistry》2001,27(6):401-406
A new molecular semiconductor, (Doet)2ReO4(Doet is (1,4-dioxanediyl-2,3-dithio)ethylenedithiotetrathiafulvalene), is synthesized and examined by X-ray diffraction analysis. The crystal structure of (Doet)2ReO4is formed by [Doet]+1/2layers with isle [ReO4]–anions located between them. The Doet radical cations from the adjacent layers are linked by intermolecular hydrogen interactions of the O···H type. 相似文献
102.
V. G. Bazhenov V. L. Kotov S. V. Krylov V. V. Balandin A. M. Bragov E. V. Tsvetkova 《Journal of Applied Mechanics and Technical Physics》2001,42(6):1083-1089
An experimental method for determining the force of resistance to penetration of a deformable impactor into soft soil was developed in the inverted formulation: the impactor and the target exchange roles and the necessary parameters of contact interaction are recorded in an immovable measuring rod (impactor). To verify the basic principles of this experimental technique, wave processes were analyzed numerically using a modified Godunov's scheme. The applicability of various models of soil deformation was studied, and the calculation results obtained were compared with experimental data. 相似文献
103.
A. A. Kotov L. A. Vaishnene V. G. Vovchenko Yu. A. Gavrikov V. V. Polyakov M. G. Tverskoi O. Ya. Fedorov T. Fukahori Yu. A. Chestnov A. V. Shvedchikov A. I. Shchetkovskii 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(6):809-811
The results of measuring total cross sections for proton-induced fission of natPb, 209Bi, 232Th, 233U, 235U, 238U, 237Np, and 239Pu nuclei at proton energies from 200 to 1000 MeV are reported. The measurements were carried out in steps of ≈100 MeV. Complementary fission fragments were detected in coincidence by two parallel-plate avalanche gas counters placed in the beam line on both sides of the thin target close to it. Energy and isotope dependences of the fission cross sections are analyzed. 相似文献
104.
A. Yu. Kotov 《JETP Letters》2018,108(6):352-355
The sphaleron transition rate in gluodynamics at the temperature T /Tc = 1.24 has been calculated by lattice simulation. The calculations involve the Kubo formula, which relates the sphaleron transition rate to the correlation function of the topological charge density. The gradient flow method has been used to calculate the correlation function of the topological charge density. The Kubo formula has been inverted by the Backus–Gilbert method. The results have been compared to those obtained by other methods. 相似文献
105.
O. I. Kotov L. B. Liokumovich S. I. Markov A. V. Medvedev A. V. Khlybov 《Technical Physics》2004,49(1):71-75
Mechanisms of polarization modulation in a single-mode fiber that modulate the phase difference between polarization modes without affecting their amplitudes are considered. A coefficient that characterizes the efficiency of cylindrical piezoceramic modulators and is independent of their resonant properties is introduced. Analytical expressions for this coefficient for different modulation mechanisms are derived. The lateral pressure on the fiber is shown to provide the highest efficiency. For isotropic fibers, a modulator with a squeezing covering, which increases significantly its efficiency, is studied. For anisotropic fibers, the most appropriate way of phase difference modulation is longitudinal extension, in which case the birefringence axes do not have to be matched. In most cases, the measured and predicted efficiencies are in good correspondence. 相似文献
106.
We present the results of experimental studies of the spectra of the stimulated electromagnetic emission excited in the ionosphere
by powerful radio waves during the pump wave frequency sweeping near the forth (n = 4) and fifth (n = 5) harmonics of the electron cyclotron frequency nf
ce. The frequency sweep was carried out for long (continuous) pumping in vertical and inclined directions (at 14° and 18° south
of the zenith), as well as for the pulse diagnostic wave both with and without additional pumping far from the gyroharmonics.
The dependences of the spectral features of the stimulated electromagnetic emission on the ratio between the pump-wave frequency
f
0 (or on the diagnostic-wave frequency fDW) and nf
ce were analyzed. It is found that near the multiple gyroresonance, different spectral features of the stimulated emission are
quenched at the same frequency for different pump-wave frequencies. For a sufficiently large inclination of the pump wave
beam from the vertical direction, the intensity of the stimulated electromagnetic emission is notably decreased for f
0 ≲ nf
ce as compared with f
0 > nf
ce.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 6, pp. 461–476, June 2008. 相似文献
107.
108.
109.
We present new experimental results on the investigation of the dynamic properties of sand soil on the basis of the inverse experiment technique using a measuring rod with a flat front-end face. A limited applicability has been shown of the method using the procedure for correcting the shape of the deformation pulse due to dispersion during its propagation in the measuring rod. Estimates of the pulse maximum have been obtained and the results of comparison of numerical calculations with experimental data are given. The sufficient accuracy in determining the drag force during the quasi-stationary stage of penetration has been established. The parameters of dynamic compressibility and resistance to shear of water-saturated sand have been determined in the course of the experimental-theoretical analysis of the maximum values of the drag force and its values at the quasi-stationary stage of penetration. It has been shown that with almost complete water saturation of sand its shear properties are reduced but remain significant in the practically important range of penetration rates. 相似文献
110.
Acoustical Physics - Abstract—For broadband modulation of the intensity of optical radiation, the tandem arrangement two acousto-optic (AO) Bragg cells are proposed in which acoustic waves... 相似文献