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91.
A method of solving the Boltzmann equation on the basis of expansion in Maxwell distributions (Maxwellians) is developed. The calculation of the collision integral consists of two stages: calculation of a two-Maxwellian collision integral and its subsequent expansion in Maxwellians. A special numerical procedure is proposed for approximating functions of one and two variables by a finite number of exponentials; the mean-square deviation of the accurate and approximate functions is minimized and certain moments of these functions are brought into agreement. For a solid-sphere model, the two-Maxwellian collision integral comprises a set of 24 functions over the whole range of the parameters investigated. The Euler method is used to examine the equalization of velocities and temperatures in the gas (quasishock) and resonance recharging of ions on atoms. The accuracy of the solutions obtained is estimated.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 132–141, September–October, 1977. 相似文献
92.
A. V. Eremeev R. S. Él'kinson É. É. Liepin'sh 《Chemistry of Heterocyclic Compounds》1978,14(3):278-282
The corresponding -amino ketone hydrazones were obtained by reaction of 2,2-dimethyl-3-phenylazirine with hydrazine, N,N-dimethylhydrazine, methylhydrazine, and semicarbazide. It was established that unsymmetrical azines are formed in the reaction of 2-amino-2-methyl-1-phenyl-1-propanone hydrazone with aliphatic and cyclic ketones. The corresponding tetrahydro-1,2,4-triazines were obtained in the case of the analogous reaction with aliphatic and aromatic aldehydes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 342–346, March, 1978. 相似文献
93.
94.
Yu. K. Grishin Yu. A. Strelenko Yu. A. Ustynyuk A. A. Érdman I. V. Shchirina-Éingorn I. I. Kritskaya 《Russian Chemical Bulletin》1982,31(5):921-926
Conclusions The199Hg NMR spectra of compounds of the type HgCC=C and HgCC=0 have been studied and it has been shown that C-Hg/ conjugation produces a sharp increase in the shielding of the mercury nucleus.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1038–1042, May, 1982. 相似文献
95.
Reaction of N-arylethylenimines with carbon dioxide in the presence of tetraethylammonium bromide gives N-aryl-2-oxazolidones, with N,N-diarylpiperazines as by-products. Carbon disulfide reacts with N-arylethylenimines under similar conditions to give 11 copolymers, together with small amounts of N-arylthiazolidine-2-thiones. Carbon oxysulfide gives copolymers only. The copolymers are converted at 250° C into N-arylthiazolidine-2-thiones and N-arylthiazolidones, respectively. N-Arylethylenimines react with phenyl isothiocyanates to give 2-phenylimino-3-arylthiazolidines.For part III, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 5, pp. 611–615, May, 1970. 相似文献
96.
Reaction of aqueous solutions of salts of acrylic acids with thioepi chlorohydrin affords thietyl acrylates, which on hydrolysis give 3-hydroxythietane, and on oxidation with hydrogen peroxide give 3-hydroxythietane 1,1-dioxide. The diene synthesis was carried out with these acrylates, and also with acryloyl and methacryloyl isothiocyanates.The authors thanks M. I. Mironova for the IR spectra and the elemantal analyses. 相似文献
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