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991.
Conclusions It was deduced that fluorine is in a -combined state in the anion radicals we studied; this was based on an analysis of the EPR spectra of a series of fluoronitroalkane anion radicals.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 458–460, February, 1969.In conclusion, the authors express their appreciation to A. A. Fainzil'berg for his interest in our work.  相似文献   
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995.
The kinetics and mechanism of reaction of arylhydrazones with molecular oxygen were studied by gas volumetry. The reaction rate was studied in relation to the structure of arylhydrazone and kind of the solvent. The inhibiting power of the compounds toward initiated oxidation of ethylbenzene was evaluated, and the most effective compounds were found, judging from the ratio of the rate constants of the reactions with molecular oxygen and with peroxy radicals arising in the course of ethylbenzene oxidation.  相似文献   
996.
Selective dehydrobromination of 1,2-dibromo-1-phenylethane to -bromostyrene was effected under conditions of phase-transfer catalysis in systems containing KOH, toluene, and tetraalkylammonium bromides. The high selectivity of the catalytic systems originates from stabilization by lipophilic cation of the phase-transfer catalyst of a E1cb-like transition state in the E2 mechanism. In the presence of a catalytic amount of lipophilic alcohols, phenylacetylene was obtained. Substrate activation by alcohol molecules is explained by enhancement of the acceptor power of halogen atoms due to solvation and by increased mobility of hydrogen atoms.  相似文献   
997.
Cellulose myristate samples with a degree of substitution of 230–250 have been studied by the methods of molecular hydrodynamics (viscometry, analytical ultracentrifugation (flotation), and isothermal translational diffusion) in chloroform in the range M = (56–652) × 103. The experimental evidence has been interpreted within the framework of the generalized wormlike Yamakawa-Fuji model with the following parameters: the persistence length a = 115 × 10?8 cm, the chain diameter d = 45 × 10?8 cm, and the molecular mass per unit chain length M L = 270 × 108 cm?1. It has been inferred that the polymer dissolves in chloroform in the form of dimers.  相似文献   
998.
Using the Zimmennan-Pimentel potential, we have calculated the basic atomic coordinates of the unit cell of the gas hydrate HS-lframework. A minimum change in the strain energy of hydrogen bonh UH fakes place in formation of this framework from ice Ih. The dependence of UH on the lattice parameters is derived.Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 34, No. 5, pp. 175–178, September–October, 1993.Translated by T. Yudanova  相似文献   
999.
Conclusions The analysis of EET in the SC-approximation that has been carried out on the example of MSB showed that the use of the FO basis instead of the AO basis gives additional information on the relationship between the energies of transitions of the chromophoric (benzene) molecule and its substituted derivatives.In the FO basis the decomposition of the EET into the fragmental and interfragmental components becomes natural. The value of the fragmental components is determined by the LN of the transition MO in the separate fragments, while that of the one-electronic energies and the coulombic and exchange integrals of the fragment (the chromophore) are approximately transferable parameters.Since the LN are dependent on the degree of mixing of the FO of the fragments the study of the relationship between the transition energies of the SC-transitions in the chromophoric molecule and the fragmental components in the substituted molecule is reduced to the study of formation the LCFO MO. Moreover, the LCFO MO makes it possible to find a relationship between the SC-transitions even when the LCAO MO of the two molecules are not commensurable. This makes it possible to carry out a classification of the SC-transitions in MSB according to the SC-transitions of benzene.We wish to express our gratitude to A. L. Gineitite for useful comments made during the preparation of the article.Institute of Biochemistry, Lithuanian Academy of Sciences. Institute of Theoretical Physics and Astronomy, Lithuanian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 6, pp. 45–56, November–December, 1992.  相似文献   
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