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991.
We discuss here the effect of dissipation of relative angular momentum on fluctuations of excitation functions in dissipative heavy-ion collisions. Dissipation and fluctuation of relative angular momentum modify and smooth the time-angle localization of the rotating dinuclear system. The secondary maxima in the energy correlation function of the cross-section shift to smaller values of the energy difference, the shift depending on the relaxation time and the diffusion coefficient for angular-momentum dissipation. The results are illustrated for the collision28Si(E
lab=130 MeV)+48Ti.Partly supported by the Alexander von Humboldt Foundation 相似文献
992.
The magnetic susceptibility of Cdx-Hg1–x–yMnySe(x 0.1, 0 y 0.1) in the temperature range 77–300 K is investigated. According to the usual model, the dependence Mn–1=f(T) is due to clusters in the form of closely spaced Mn atoms, between which there may be both direct and indirect (through a nonmagnetic atom) exchange interaction, leading to antiferromagnetic ordering.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 65–67, August, 1991. 相似文献
993.
Superlattices based on bcc ones are considered that have space groups P
3ml or P3ml and tripled parameters in the initial cubic axes. Expressions are derived for the concentration and displacement waves corresponding to these superlattices.Translated from Izvestiya Vysshikh Uchebynkh Zavedenii, Fizika, No. 9, pp. 91–96, September, 1991. 相似文献
994.
V. M. Govorun V. E. Tretiakov N. N. Tulyakov V. B. Fleurov A. I. Demin A. Yu. Volkov V. A. Batanov A. B. Kapitanov 《International Journal of Infrared and Millimeter Waves》1991,12(12):1469-1474
This paper describes the effect of far-infrared radiation on the activity and secondary structure of albumin, alcohol dehydrogenase, peroxidase and trypsin. For the first time the data obtained allowed a conclusion that enzymatic activity changes under the influence of radiation having the wavelength of 90 m. No disruptures of polypeptide chains or oligomerization of proteins were obtained. It has been shown that albumin secondary structure calculated from circular dichroism spectra changes lineary according to dose of laser emission.Abbreviations FIR
far-infarred radiation
- CD
circular dichroism
- ADG
alcohol dehydrohenase
- PXD
peroxidase
- ANS
1-anilinenaphalene-8-sulfonic acid 相似文献
995.
A. B. Zolotoi P. M. Lukin S. V. Konovalikhin M. Yu. Skvortsova O. E. Nasakin L. O. Atovmyan 《Chemistry of Heterocyclic Compounds》1991,27(4):413-419
The problems of the structure—property interrelationship of 3-imino-2-oxabicyclo[2.2.1]heptane derivatives are discussed on the basis of x-ray diffraction studies (XDS). A pathway for the formation of the bicyclic compounds is proposed, and the realization of spirans in the reaction of sym-tetracyanoethane with conjugated cyclic systems containing s-cis C=C and C=O fragments is substantiated. The factors responsible for the syn orientation of the oxygen atom and the N-substituent of the imino group are analyzed. It is shown that a change in the steric hindrance in the bicyclic compounds leads to a change in the conformation of the latter. The reasons for the shortening of the Csp3-Csp3, Csp3-Csp and C=N exo bonds and the correlation of the XDS and IR spectroscopic data are examined. From the XDS data for N-bromo-substituted imines, a model for Br+...NC electrophilic attack was proposedCommunication 16 from the series Chemistry of 1,1,2,2-tetracyanoethane. See [1] for Communication 15.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 519–526, April, 1991. 相似文献
996.
A. V. Metelitsa M. I. Knyazhanskii N. V. Volbushko I. Yu. Grishin Yu. M. Chunaev N. M. Przhiyalgovskaya 《Chemistry of Heterocyclic Compounds》1991,27(9):1012-1015
Only E Z isomerization is observed for the steady irradiation of fulgides based on 1,2-dimethyl-3-formylindole in contrast to the analogs based on 3-acetylindole. The formation of cyclic photoisomers is registered by the method of impulse photolysis. The presence of a methyl substituent in the position 2 of the indole portion leads to a significant increase in the stability of the photochromic system. The introduction of alternative reaction centers of cyclization in the form of bulky phenyl groups leads to the suppression of electrocyclization at the position 2 of the indole portion and the formation of dihydronaphthalene structures.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1255–1258, September, 1991. 相似文献
997.
S. Yu. Ryabova Yu. I. Trofimkin L. M. Alekseeva L. S. Khabarova V. G. Granik 《Chemistry of Heterocyclic Compounds》1991,27(3):278-283
The reaction of 2-(N,N-dimethylaminomethylene)indolin-3-one and 2-methyl-3-ethoxycarbonyl-5-(N,N-dimethyl aminomethylene)-2-pyrrolin-4-one with acyl halides was used to synthesize immonium salts, the aqueous hydrolysis of which leads to 2-formyl-3-hydroxyindole and 4-hydroxy-5 formylpyrrole derivatives. -Cyano--(2-indolyl)- and -cyano--(5-pyrrolyl)acrylic acid derivatives were synthesized by reaction of immonium salts of the pyrrole series, 4 acyloxy-5-formylpyrrole and 2-formyl-3-acyloxyindole derivatives, with compounds that contain an active methylene group.See [1] for Communication 63.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 343–348, March, 1991. 相似文献
998.
M. K. Polievktov O. A. Petrishcheva S. Yu. Ryabova T. V. Golovko V. G. Granik 《Chemistry of Heterocyclic Compounds》1991,27(5):511-516
The polarographic behavior of derivatives of 2-aminomethyleneindoxyl and 3-aminomethyleneoxindole in anhydrous DMF has been studied and the results compared with data on the polarographic reduction of substituted aminomethyleneacetophenones and of related enaminoketones and eneaminoamides. It is established that the ease of reduction is determined by the nature of the substituent on the enamine and indole nitrogen atoms and also by the presence or absence of an -methyl group in the -position of the eneamines (for noncyclic enaminoketones).For Communication 66, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 642–648, May, 1991. 相似文献
999.
A. Zh. Turmukhambetov S. M. Adekenov K. M. Turdybekov Yu. V. Gatilov 《Chemistry of Natural Compounds》1991,27(3):292-295
By extraction with acetone and chromatography of the resin on a column of type KSK silica gel the epigeal part ofArtemisia gracilescens has yielded the new sesquiterpene lactone gracilin, for which the structure of 1-oxo-6, 7,11(H)-eudesm-4(5)-en-6,12-olide is proposed.Institute of Organic Synthesis and Coal Chemistry, Academy of Sciences of the Kazakh SSR, Karaganda. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 339–343, May–June, 1991. 相似文献
1000.
I. I. Kandror M. A. Galkina I. O. Bragina B. D. Lavrukhin Yu. N. Belokon' Yu. G. Gololobov 《Russian Chemical Bulletin》1992,41(10):1928-1930
Ethyl -cyanocarylate undergoes the Michael reaction with strong CH-acids (pK
a < 13) in the presence of strong basic amines such as butylamine, piperidine, and triethylamine. Only polymerization of ethyl -cyanoacrylate occurs under the same conditions with weaker CH-acids in the presence of less basic amines such as aniline, N-methylaniline, and pyridine.A. N. Nesmeyanov Institute of Organometallic Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2449–2452, October, 1992. 相似文献