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11.
Variation of cellulolytic activity of an enzymatic specimen and of its composition with microcrystallic cellulose upon mechanical
treatment has been studied. 相似文献
12.
Yu. I. Bychkov Yu. D. Korolev G. A. Mesyats A. P. Khuzeev I. A. Shemyakin 《Russian Physics Journal》1978,21(7):898-901
Beam-controlled current flow is investigated in an Ar-SF6 mixture at atmospheric pressure. It is shown that electron attachment to SF6 molecules plays an important role in the charge-dparticle balance, and the attachment constant is determined. The discharge energy properties are studied.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 72–76, July, 1978. 相似文献
13.
G. A. Domrachev V. K. Khamylov B. A. Nesterov V. T. Bychkov I. V. Lomakova 《Russian Chemical Bulletin》1977,26(12):2594-2595
Conclusions The decomposition of tetracarbonyl(triethylgermyl) cobalt in a flow vacuum system at 150° gives the high-temperature-modification of cobalt, while CoGe and CoGe2 are formed at 400°.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2804–2806, December, 1977. 相似文献
14.
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
15.
V. V. Lapachev O. A. Zagulyaeva O. P. Petrenko S. F. Bychkov V. P. Mamaev 《Chemistry of Heterocyclic Compounds》1984,20(6):676-680
The existence of a pyrimidinyl-pyrimidinylidene tautomeric equilibrium in solutions of 2-pyrimidinylcyanoacetic acid esters in CDCl3 was observed. Unsymmetrically substituted compounds form two types of ylidene tautomers that differ with respect to the position of the NH proton, the ratio between which is controlled by the substituents in the 4 (6) position. The introduction of both donor and acceptor substituents into the 5 position of the pyrimidine ring increases the amount of the pyrimidine form. The same thing occurs when the polarity of the solvent is decreased. The addition of DMSO or DMF to CDCl3 leads to conversion of the intrachelate ylidene tautomers to unchelated tautomers. Protonation (CF3COOH) shifts the equilibrium to favor the ylidene tautomer that has higher basicity.See [1] for communication 5.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 827–831, June, 1984. 相似文献
16.
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
17.
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
18.
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
19.
20.
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