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81.
82.
Gear's predictor-corrector multistep method is applied to a rigid system of nonlinear ordinary differential equations, describing vibrational kinetic processes in molecular (diatomic) gas. The applicability of Naidis's formulas, for the linear problem is studied. The evolution of the starting Boltzmann distribution to the quasiequilibrium Trinor distribution is studied. The vibrational relaxation curves are calculated taking into account VV and VT processes and the possibilities of a more complicated starting physical model are examined.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 57–62, March, 1985. 相似文献
83.
The first observation of both two-phonon and polariton hyper-Raman scattering in rutile crystal is reported. The effect of two-phonon states on Au-polariton dispersion has been found. 相似文献
84.
Lagatsky AA Sarmani AR Brown CT Sibbett W Kisel VE Selivanov AG Denisov IA Troshin AE Yumashev KV Kuleshov NV Matrosov VN Matrosova TA Kupchenko MI 《Optics letters》2005,30(23):3234-3236
We report the first demonstration, to our knowledge, of soft-aperture Kerr-lens mode locking in a diode-pumped femtosecond Yb3+:YVO4 laser. Near-transform-limited pulses as short as 61 fs are generated around a center wavelength of 1050 nm with an output power of 54 mW and a pulse repetition frequency of 104.5 MHz. This is, to our knowledge, the shortest pulse generated directly from an Yb laser having a crystalline host material. The femtosecond operation has a mode-locking threshold at an absorbed pump power of 190 mW. The nonlinear refractive indexes of the Yb3+:YVO4 crystal have been measured to be 19 x 10(-16) cm2/W and 15 x 10(-16) cm2/W for the sigma and pi polarizations, respectively, at 1080 nm. 相似文献
85.
A. M. Denisov 《Differential Equations》2004,40(9):1221-1232
In the present paper, we consider a semilinear hyperbolic system with coefficients depending on different solution components. We study the inverse problem of finding one of the coefficients on the basis of additional information on the solution. The proof of the existence theorem for the inverse problem is based on the reduction of the latter to a nonlinear operator equation, which is a nonlinear integro-differential equation for the unknown coefficient. This approach was used in [1] to prove the existence of a solution of the inverse problem for a quasilinear hyperbolic equation. Inverse problems for quasilinear hyperbolic equations and systems were also considered in [2–6] and other papers.Translated from Differentsialnye Uravneniya, Vol. 40, No. 9, 2004, pp. 1155–1165.Original Russian Text Copyright © 2004 by Denisov. 相似文献
86.
Bratman VL Cross AW Denisov GG He W Phelps AD Ronald K Samsonov SV Whyte CG Young AR 《Physical review letters》2000,84(12):2746-2749
First bandwidth measurements of a novel gyrotron amplifier are presented. The coupling between the second harmonic cyclotron mode of a gyrating electron beam and the radiation field occurred in the region of near infinite phase velocity over a broad bandwidth by using a cylindrical waveguide with a helical corrugation on its internal surface. With a beam energy of 185 keV, the amplifier achieved a maximum output power of 1.1 MW, saturated gain of 37 dB, linear gain of 47 dB, saturated bandwidth of 8.4 to 10.4 GHz ( 21% relative bandwidth), and an efficiency of 29%, in good agreement with theory. 相似文献
87.
V. Yu. Denisov 《Physics of Atomic Nuclei》2007,70(2):244-257
It is shown that the positions of deep local minima of shell corrections associated with magic numbers in the region of superheavy nuclei depend on the parameters of the central and spin-orbit mean-field potentials. The accuracy of nuclear-mass predictions made within various models for superheavy nuclei is analyzed. 相似文献
88.
Sergey A. Denisov 《Journal of Functional Analysis》2008,254(8):2186-2226
For a large class of Schrödinger operators, we introduce the hyperbolic quadratic pencils by making the coupling constant dependent on the energy in the very special way. For these pencils, many problems of scattering theory are significantly easier to study. Then, we give some applications to the original Schrödinger operators including one-dimensional Schrödinger operators with L2-operator-valued potentials, multidimensional Schrödinger operators with slowly decaying potentials. 相似文献
89.
G.G. Denisov S.V. Kuzikov N. Kobayashi 《International Journal of Infrared and Millimeter Waves》2001,22(12):1735-1760
An application of remote RF beam steering concept, based on image multiplication phenomena in a corrugated square waveguide, to electron-cyclotron plasma heating and current drive for ITER has been considered. In the present paper high attention is paid to studies of reliability of the remote steering capability in realistic waveguide condition. Different factors, could limit efficiency (RF breakdown, random technological spread of parameters, and heating of system), are simulated. Polarization properties of the remote steering antenna, arising due to non-ideal corrugation, are investigated. It is suggested a new configuration of antenna to be not sensible to corrugation parameters. RF analysis of the system, supplemented by dog-legs and a vacuum window, is also presented. A new way to use beating wave transmission in the remote steering waveguide is suggested, in order to reduce losses caused by mitre bends. 相似文献
90.
The lasing frequencies of a ring laser with counterpropagating electromagnetic waves are calculated for the case when a part of the laser circuit is subjected to a constant electromagnetic field. It is demonstrated that, according to equations of the parametrized post-Maxwellian electrodynamics of vacuum, two waves with different planes of polarization and frequencies should propagate in each direction of the ring laser. The analysis has shown that, with the help of advanced ring lasers and external electromagnetic fields attainable in the laboratory, the post-Maxwellian parameters can be measured with a precision that would be sufficient to verify the most popular theoretical models of the nonlinear electrodynamics of vacuum. 相似文献