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721.
S. N. Vlasov N. A. Zavolsky V. E. Zapevalov E. V. Koposova M. A. Moiseev 《Radiophysics and Quantum Electronics》2009,52(9):642-654
We study theoretically multistage cavity resonators as well as the gyrotrons manufactured on their basis. Coupled cavities
with mode conversion and echelette cavities are particular cases of such devices. The possibilities of reducing the diffraction
Q-factor of the operating mode of a cavity, with the preservation of its selective properties and significant increase in
the gyrotron radiation power, and provision of high efficiency and acceptable heat ohmic load of the cavity at the first harmonic
of the gyrofrequency are considered. Achievable parameters of the gyrotrons at the second and third harmonics with typical
electron guns and cryomagnetic systems are analyzed. 相似文献
722.
Tsodikov M. V. Kugel V. Ya. Slivinskii E. V. Yandieva F. A. Mordovin V. P. Moiseev I. I. 《Russian Chemical Bulletin》2001,50(7):1201-1207
Transformations of carbon dioxide catalyzed by the hydride form of [TiFe0.95Zr0.03Mo0.02]Hx, by the industrial Pt/Al2O3 catalyst, and by a mixture of the above materials were studied. Study of the thermal desorption of H2 showed the presence of two forms of absorbed hydrogen, namely, the weakly bound hydrogen, which is evolved from the intermetallic structure on heating to 430 °C under Ar, and the strongly bound hydrogen (SBH), which remains in the intermetallic compound at higher temperatures (up to 700 °C). In a carbon dioxide medium, the SBH enters into selective CO2 reduction to give CO at 350—430 °C and 10—12 atm. The selectivity of the formation of CO reaches 80—99% for conversion of CO2 between 50—70%, the SBH being consumed almost entirely for the reduction of CO2. In the presence of the mixed catalyst, conjugate reactions proceed efficiently; dehydrogenation of cyclohexane yields hydrogen, which is consumed for CO2 hydrogenation. 相似文献
723.
Fomina I. G. Talismanov S. S. Sidorov A. A. Ustynyuk Yu. A. Nefedov S. E. Eremenko I. L. Moiseev I. I. 《Russian Chemical Bulletin》2001,50(3):515-519
The reactions of N-methyl-ortho-phenylenediamine (1) with K2MCl4 (M = Pd or Pt) were investigated. At the first stage, the tetraamine dicationic complexes [(C6H4(NH2)(NMeH))2M]Cl2 were formed. Oxidation of these compounds with atmospheric oxygen in an alkaline medium afforded the neutral semiquinonediimine complexes [C6H4(NH)(NMe)]2M. The structures of the {[(C6H4)(NH2)(NHMe)]2Pd}Cl2 and [C6H4(NH)(NPh)]2Pt complexes were established by X-ray diffraction analysis. 相似文献
724.
Russian Journal of Organic Chemistry - 相似文献
725.
Kudryashov S. Yu. Onuchak L. A. Voronkov A. V. Buryak A. K. Moiseev I. K. 《Russian Chemical Bulletin》2000,49(12):1988-1992
The adsorption equilibrium constants for adamantane, 1-fluoro-, 1-chloro-, 1,3-difluoro-, 1,3-dichloro-, 1,3-dibromo-, and 1-hydroxyadamantane, and methyl 1-adamantyl ketone were determined by gas chromatography. The results were compared with molecular statistical calculations based on the known atomic-atomic potentials of the interaction of atoms of the sorbate molecule with the C atom of graphitized thermal carbon black (GTCB). The experimental adsorption heats exceed the calculated values by 3-10 kJ mol-1. The reasons for this divergence are discussed. The changes in the adsorption entropy show that the molecules of the studied compounds form a layer of the ideal dimeric gas on the GTCB surface upon adsorption. 相似文献
726.
S. N. Moiseev 《Radiophysics and Quantum Electronics》2000,43(3):238-244
Using the method of generative processes, we construct a model of a random linear symmetric stable Markov process, which is
a natural generalization of the Markov Gaussian process and preserves its main property: invariance with respect to arbitrary
linear transformations. Methods for analyzing such processes are developed. In particular, it is proposed to use the information
correlation function as a characteristic of the pair dependence between the process values at different times. This function
is used to calculate the determination interval of the process.
Voronezh State University, Voronezh, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 43,
No. 3, pp. 264–270, March, 2000 相似文献
727.
Asaoka Y Shikaze Y Abe K Anraku K Fujikawa M Fuke H Haino S Imori M Izumi K Maeno T Makida Y Matsuda S Matsui N Matsukawa T Matsumoto H Matsunaga H Mitchell J Mitsui T Moiseev A Motoki M Nishimura J Nozaki M Orito S Ormes JF Saeki T Sanuki T Sasaki M Seo ES Sonoda T Streitmatter R Suzuki J Tanaka K Tanizaki K Ueda I Wang JZ Yajima Y Yamagami Y Yamamoto A Yamamoto Y Yamato K Yoshida T Yoshimura K 《Physical review letters》2002,88(5):051101
The energy spectra of cosmic-ray low-energy antiprotons ( *p's) and protons ( p's) have been measured by BESS in 1999 and 2000, during a period covering reversal at the solar magnetic field. Based on these measurements, a sudden increase of the *p/p flux ratio following the solar magnetic field reversal was observed, and it generally agrees with a drift model of the solar modulation. 相似文献
728.
N. I. Zaitsev E. V. Ilyakov I. S. Kulagin V. K. Lygin V. N. Manuilov M. A. Moiseev A. S. Shevchenko 《Radiophysics and Quantum Electronics》2006,49(8):612-616
We show that it is possible to increase significantly (up to one-half of the Langmuir value) the current of the electron beam
in a magnetron-injection gun operated in the nonadiabatic regime of formation of a relativistic helical electron beam if the
velocity spread is small. The obtained beam has a current of 200 A, a velocity spread of about 10%, a pitch factor of about
1, and an electron energy of 340 keV.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radio.zika, Vol. 49, No. 8, pp. 680–685, August 2006. 相似文献
729.
The technique of quantum memory based on the use of a photon echo in gases is studied theoretically taking into account three-dimensional specific features in the propagation of light fields and the motion of atoms in a gas. Analytical solutions describing the effects of atomic motion and diffraction of light fields on the properties of the quantum state of light being reconstructed are obtained. Estimates of the parameters of light fields that are optimum for realizing the quantum memory based on a photon echo in gaseous media are presented. 相似文献
730.