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981.
Trofimov B. A. Malysheva S. F. Gusarova N. K. Tatarinova A. A. Henkelmann J. 《Russian Journal of Organic Chemistry》2003,39(9):1356-1357
Russian Journal of Organic Chemistry - 相似文献
982.
Khizhan E. I. Filippenko T. A. Nikolaevskii A. N. 《Russian Journal of Applied Chemistry》2004,77(3):423-426
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
983.
N. M. Zadymova N. V. Karmasheva M. V. Poteshnova N. N. Tsikurina 《Colloid Journal》2002,64(4):400-405
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
984.
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
985.
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
986.
987.
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
988.
Ponomarev N. E. Stambirskii M. V. Dvorko G. F. 《Russian Journal of General Chemistry》2002,72(1):79-85
The salt effect on the rate of dehydrobromination of 3-bromocyclohexene in PhNO2 depends on the nature of the verdazyl indicator. With triphenylverdazyl and its chloro and nitro derivatives in the presence of Et4NClO4, a normal salt effect is observed, in the presence of bromides, a superposition of normal and special salt effects, while in the presence of chlorides, a superposition of normal and special negative salt effects. With the dimethoxy verdazyl derivative, a normal salt effect is always observed. 相似文献
989.
The analysis of 31P and 15N NMR data of a series of 40 iminophosphines R-P=N-R′ reveals that the E/Z-stereochemistry of the PN double bond can be predicted
on the basis of a simultaneous comparison of the values of δ31P and 1JPN.
Received: 31 May 1996/Revised: 2 July 1996/Accepted: 5 July 1996 相似文献
990.