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971.
Conclusions A new and simple method has been found for the synthesis of 1-oxo-1-chlorophospholenes by the reaction of phosphorus trichloride, a diene, and an oxygen-donor compound, the best of which is acetone.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1847–1848, August, 1972.  相似文献   
972.
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   
973.
974.
975.
976.
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   
977.
The procedure that allows to study the kinetics of a dissolution of oleophilic nonionic surfactants in water and to determine the equilibrium values of solubility (S eq w) was proposed, based on the spectrophotometry of extremely dilute, finely dispersed o/w emulsions of these substances prepared by sonication. The equilibrium values of solubility of tetraethoxylated p-nonylphenol (Neonol AF9-4) and sorbitan monolaurate (Span-20) at 293 K in water are 3.67 × 10–5 and 1.03 × 10–5 M, respectively. For the tetraethoxylated p-nonylphenol, the equilibrium value of solubility in water determined by the proposed procedure agrees well with that determined by precision tensiometric measurements.  相似文献   
978.
The behavior of epimanool (1), epimanool oil, larixol (2), cis-abienol (3) and methyl dehydroabietate (4) on alumina impregnated with oxidants (H2CrO4 and KMnO4) has been studied. This has led to the methyl ketone (5) and norambrenolide (8) - precursors of the perfume substances 14,15,17-trinorlabdane-8,13-dione (6), 8-hydroxy-14,15-bisnorlabd-II-en-13-one (7), and methyl 7-oxodehydroabietate (14). -Levantenolide (11) has been synthesized in one stage from cis-abienol (3)for the first time.Novosibirsk Insitute of Organic Chemistry, Siberian Division of the Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 229–234, March-April, 1995. Original article submitted July 25, 1994.  相似文献   
979.
980.
The main feature of fluorite structure type is four families of crystallographic planes with dense trigon cation nets which are mutually oriented as the faces of a regular octahedron. A complicated cation composition may cause lowering of general symmetry to tetragonal (only one four-fold axis remains in the octahedral complex), rhombohedral (one three-fold axis), orthorhombic, and monoclinic. The geometric parameters of the cation sublattice remain constant. They are close to the parameters of the ideal face-centered cubic cation sublattice of fluorite (the measure of similarity is 1.00–0.81). This is true for all analyzed fluoride structures and some U4+, Th4+, Zr, and Ln oxyfluorides. Thus, the concept is confirmed that the crystalline state is determined by systems of parallel planes filled by dense heavy-atom nets. Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Institute of Crystallography, Russian Academy of Sciences. Translated fromZhurnal Struktumoi Khimii, Vol. 35, No. 1, pp. 71–80, January–February, 1994. Translated by T. Yudanova  相似文献   
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