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951.
V. V. Yanilkin V. P. Gubskaya N. V. Nastapova L. Sh. Berezhnaya I. E. Ismaev Yu. Ya. Efremov I. A. Nuretdinov 《Russian Chemical Bulletin》2004,53(12):2793-2797
The combined electrochemical reduction of fullerene C60 in the presence of p-bromo-benzoyldibromomethane or bis(diisopropoxyphosphoryl)dibromomethane at a brass electrode in a mixed solvent o-dichlorobenzene-MeCN (3:1 v/v)/0.05 M Bu4NBF4 at room temperature affords 61-(p-bromobenzoyl)methano[60]fullerene or 61,61-bis(diisopropoxyphosphoryl)methano[60]fullerene, respectively, in 50% yields.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2681–2685, December, 2004. 相似文献
952.
Dynamical response of a passivation model subjected to parametric periodic and stochastic perturbations is studied numerically. In response to weak periodic modulation, the system exhibits a rich variety of resonance behavior and induced dynamics, including periodically induced oscillation, birhythmicity, switching between two bistable states, selection of one of the bistable states, mixed-mode and chaotic oscillations. These phenomena are discussed in terms of the stability of saddle focus and an incomplete homoclinic connection. Our numerical results are relevant for a wide class of electro-chemical oscillatory systems, where the re-injection of unstable trajectory on the neighborhood of a saddle focus is a typical feature in the phase space. 相似文献
953.
L. I. Mastafanova K. F. Turchin M. I. Evstratova Yu. N. Sheinker L. N. Yakhontov 《Chemistry of Heterocyclic Compounds》1985,21(3):305-309
The reduction in an acidic medium over a platinum catalysts of 2,4-, 2,5-, and 2.6-pyridinedicarboxylic acids gave cis-2,4-, -2,5-, and -2,6-piperidinedicarboxylic acids, heating of which in an alkaline medium led to thermodynamically equilibrium mixtures of diastereomers. Individual trans-2,5-piperidinecarboxylic acid was isolated. The configurations of the 2,4-, 2,5-, and 2,6-piperidinedicarboxylic acids and their methyl esters were established by means of the PMR spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 367–371, March, 1985. 相似文献
954.
A. N. Kost V. I. Minkin V. A. Budylin Yu. V. Kolodyazhnyi V. V. Druzhinina M. A. Yurovskaya 《Chemistry of Heterocyclic Compounds》1982,18(12):1271-1276
On the basis of a comparison of the experimental dipole moments with the calculated values, as well as data from the UV, IR, and PMR spectra, it is shown that 3-acylindoles exist in the form of equilibrium mixtures of the planar S-cis and S-trans conformers with preponderance of the latter.DeceasedTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1647–1652, December, 1982. 相似文献
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957.
A. D. Margolin E. A. Fushman L. Yu. Ustynyuk S. S. Lalayan 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(8):1181-1190
The thermodynamic parameters of formation of ions in the system AlMe3 + electron donor (D) in the presence and absence of water microimpurities were determined. The structure of these ions was studied and their concentration in nonpolar media was estimated for the example of D = pyridine. The conclusion was drawn from the results of calculations that the participation of water resulted in a substantial increase in the concentration of ions. 相似文献
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