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31.
Results are presented from experimental studies of the initial stage of an air discharge initiated in a linearly polarized quasi-optical microwave beam. The discharge was excited at an air pressure at which the electron-neutral collision frequency in the discharge plasma was considerably higher than the circular frequency of the electromagnetic field and at a microwave field amplitude close to the threshold field for air breakdown. The experiments revealed relatively bright plasma channels stretched along the microwave electric field. The development rate of these channels and their characteristic transverse dimensions are estimated. A comparison of the experimental data and theoretical estimates indicates that the channels observed arise due to the onset of thermal ionization instability in the microwave discharge plasma. 相似文献
32.
Yu. I. Bychkov B. M. Kovalchuk G. P. Kuzmin G. A. Mesyats V. F. Tarasenko 《Russian Physics Journal》2000,43(5):345-351
This review paper presents the results obtained during the development and study of three high-power wide-aperture CO
2
lasers (λ=10.6 μm) pumped with a discharge controlled by an electron beam. In developing these lasers, the method of formation
of a space discharge at elevated pressures due to uniform ionization of the working mixture by an electron beam with an energy
of some hundreds of kiloelectron-volts was used, which was proposed by researchers at the Instute of High-Current Electronics
(IHCE).
Institute of High-Current Electronics, Siberian Division of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh
Uchebnykh Zavedenii, Fizika, No. 5, pp. 5–11, April, 2000. 相似文献
33.
V. D. Buchelnikov I. V. Bychkov D. A. Kuzmin S. J. Lamekhov V. G. Shavrov 《Bulletin of the Russian Academy of Sciences: Physics》2013,77(9):1120-1122
A spectrum of coupled waves in TbMnO3 with sinusoidal antiferromagnetic structure is investigated. Expressions for the activation frequencies are obtained, and temporal and spatial permittivity dispersions are considered. Frequency dependences for the reflectance of electromagnetic waves from the TbMnO3 surface are calculated. 相似文献
34.
N. M. Bychkov 《Thermophysics and Aeromechanics》2008,15(2):321-331
On the basis of experimental data for a windwheel with large-aspect-ratio (up to 14) cylinders, a method making it possible
to determine optimal parameters and main characteristics of a windwheel (power, highspeed) is proposed. Effects due to number
of cylinders, their aspect ratio and speed of rotation, stream velocity, and generator load are analysed. 相似文献
35.
V. A. Lebedev V. I. Sal’nikov V. V. Tsvetov A. V. Bychkov Yu. P. Savochkin M. V. Kormilitsyn 《Russian Journal of Applied Chemistry》2008,81(11):1904-1908
Potentialities of low-temperature (300–500°C) chlorination to remove the aluminum cladding of fuel elements and separate uranium and aluminum were studied. 相似文献
36.
37.
38.
Using the density functional theory method at the B3LYP/6-31G(d,p) theory level, the formation of hydrogen bonded complexes of L-cysteine with selenious and selenic acids is studied. In both cases, complexes formed through the carboxyl group of cysteine
mostly arise, their enthalpy of formation being of -19kcal/mol to -21 kcal/mol and the free energy of -6kcal/mol to -9kcal/mol.
The primary act of interaction in the system of hydroxyl-containing selenium compound — α-aminoacid, including the mutual
orientation of reactant molecules and the formation of intermolecular hydrogen bonds is likely to a serve as prerequisite
for the thiol group to be able to participate in the next stages (including deeper chemical transformations) of biologically
significant reactions. 相似文献
39.
Alexey Leonidovich Bychkov Kirill G. Korolev Oleg I. Lomovsky 《Applied biochemistry and biotechnology》2010,162(7):2008-2014
A new method of obtaining biologically active mannanoligosaccharides is proposed. It involves mechanical activation of the
enzymatic hydrolysis of components forming the supramolecular structure of the cell wall. Processes that take place during
mechanical treatment and enzymatic hydrolysis of yeast biomass and lead to an increase in the availability of mannanoligosaccharides
of the yeast cell walls are investigated. The efficiency of the use of mechanoenzymatic approach to obtaining mannanoligosaccharide
preparations is evaluated. 相似文献
40.
Lev M. Yagupolskii Irina I. Maletina Liubov V. Sokolenko Yurii G. Vlasenko Maria V. Drozdova Vitaliy V. Polovinko 《Journal of fluorine chemistry》2010,131(2):238-247
The aza analogues of carboxylic acids chlorides containing the NSO2CF3 and NSO2CH3 groups instead of oxygen atom were used in the Arndt–Eistert reaction. It was found that N-trifluoromethylsulfonyl-(4-fluorophenyl)-carboximidoyl chloride 1 reacts with diazomethane vigorously even at ?70 °C with formation of 1-trifluoromethylsulfonylamino-2-(4-fluorophenyl)-2,3-dimorpholine-4-yl-propane 3, 2-trifluoromethylsulfonylamino-2-(4-fluorobenzyl)-7-oxa-4-azonia-spiro[3.5]nonane 4, 2-trifluoromethylsulfonylamino-2-(4-fluorobenzyl)-1,3-dimorpholine-4-yl-propane 5 and 1-trifluoromethylsulfonylamino-2-(4-fluorobenzyl)-2,3-dimorpholine-4-yl-propane 6. Reaction of N-methylsulfonylbenzcarboximidoyl chloride 8 with diazomethane proceeds at ?15 °C yielding 4-chloro-4-methylsulfonylaminomethyl-3-phenyl-4,5-dihydro-1H-pyrazoline 9. 相似文献