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991.
A. I. Kovalev Yu. I. Lyakhovetskli M. M. Teplyakov A. L. Rusanov P. V. Petrovskii S. O. Yakushin 《Russian Chemical Bulletin》1993,42(9):1529-1535
The chemical heterogeneity of polyphenylenes obtained by trimerization poiycycio-condensation of acetylaromatic compounds has been investigated by GLC-MS analysis of the products of trimerization cyclocondensation of acetophenone. The mechanism for the formation of side products of the reaction is discussed. The presence of dypnone fragments in the polyphenylene structure results in a decrease in the thermal stability of these polymers.Deceased March, 1993.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1595–1601, September, 1993. 相似文献
992.
Yu. P. Kudryavtsev S. E. Evsyukov M. B. Guseva V. G. Babaev V. V. Khvostov 《Russian Chemical Bulletin》1993,42(3):399-413
The history of the discovery of carbyne, the chemical and physical methods used to obtain it, the analysis of its structure, and some of its properties are briefly considered. The prospects for its practical applications are discussedThis publication is based on a number of works on carbyne submitted for the Russian State Prize in the field of science and technology in 1993; performed at the A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences and the M. V. Lomonosov Moscow State University.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 450–463, March, 1993. 相似文献
993.
The enthalpies of formation (ΔH
f
o) for 23 halosubstituted radicals were determined from the published data on bond dissociation energies. The ΔH
f
o values of the corresponding molecules necessary for the calculation of ΔH
f
o of the radicals were taken from handbooks or calculated by the additive-group method. The conjugation energies of the radicals
are calculated, and the effect of substituents at the π-system on these values was shown. Errors of determination of the ΔH
f
o values of the radicals were estimated.
For Part 1, see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 643–646, April, 1998. 相似文献
994.
Karasevich E. I. Karasevich Yu. K. Shestakov A. F. Shilov A. E. 《Kinetics and Catalysis》2003,44(1):112-120
Published data on the kinetic isotope effects of the hydroxylation of deuterium-substituted methane molecules (CHD3, CH2D2, and CH3D) by methane monooxygenase are examined in the framework of the two-step nonradical mechanism through the intermediate formation of a complex containing pentacoordinate carbon. The kinetic schemes with the first step involving one, two, and three hydrogen atoms of the oxidized substrate are considered. Contrary to the widely accepted oxygen rebound mechanism, the experimental results obtained for the oxidation of various substrates by methane monooxygenase and cytochrome P450 can be explained from the viewpoint of the dynamics of a general nonradical mechanism. 相似文献
995.
Korochentsev V. V. Vovna V. I. Ustinov A. Yu. Ivanov Yu. V. 《Russian Journal of Coordination Chemistry》2002,28(12):848-850
The ab initio Hartree–Fock method with the DZA basis in single- and multideterminant approximations was used to study the electronic structure of nickel bis(acetylacetonate) and its -substituted analogs (X = Cl and CH3). The character and sequence of canonical molecular orbitals were determined; the influence of -substituents and the role of the correlation and relaxation effects were elucidated. 相似文献
996.
Dzhemilev U. M. Ibragimov A. G. Khafizova L. O. Khalilov L. M. Vasil"ev Yu. V. Tomilov Yu. V. 《Russian Chemical Bulletin》2001,50(2):297-299
1-Ethyl-2,3-fullerenoaluminacyclopropanes (EtAl)n(2-C60) were synthesized by the reaction of fullerene C60 with an excess of EtAlCl2 in the presence of Mg and using Cp2TiCl2 as the catalyst in a THF--toluene solution at 20 °C. Deuterolysis of fullerenoaluminacyclopropanes afforded a mixture of deuteriofullerenes C60Dm, where m = 6--12. 相似文献
997.
998.
999.
A. N. Kost L. N. Khaimov Yu. Dzhurakulov K. Kh. Khaidarov L. D. Lebedeva A. L. Kotov 《Chemistry of Heterocyclic Compounds》1975,11(11):1263-1266
2-Substituted or 2,2-disubstituted 4,6-dioxo-1,3-dioxanes, which are analogs of Meldrum's acid and were obtained by reaction of malonic acid with acetic anhydride and the appropriate carbonyl compound in the presence of sulfuric acid, exist in solution preferably in a single form according to the PMR and 13C NMR spectral data. Fluctuation of the CH2 group is not observed. The mass spectra are characteristic and are distinguished by splitting out of the carbonyl compound from the molecular ion or successive splitting out of CO2 and ketene molecules. The Meldrum acid analogs do not affect plant growth but have a depressive effect on the central nervous system of animals and low toxicity.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1482–1486, November, 1975. 相似文献
1000.