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981.
982.
983.
984.
V. A. Postnikov Ts. V. Kakuliya L. M. Khananashvili Yu. V. Isaev Yu. N. Novikov M. E. Vol'pin 《Russian Chemical Bulletin》1979,28(3):626-627
Conclusions The stirred reaction of graphite with molten lithium gave compounds of composition C6Li, C12Li, and C18Li, for which the identity periods and thicknesses of the filled layers were determined.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 671–672, March, 1979. 相似文献
985.
The gas-liquid chromatographic fractionation of the commercial biodegradable surfactants RO(CH2CH2O)
H (where R is an n-alkyl group and
is the number-average degree of polymerization) can be approached only for
4, as the truncation of the molecular-weight distribution occurs at higher
values. Although conversion into trimethylsily (TMS) derivatives improves the volatility of the oligomers, there is only a slight advantage in using this conversion procedure: TMS derivatives have the same elution temperature as untreated compounds above ca. 330°. The use of an internal standard as a reference compound for comparison of peak areas is a useful procedure, which has been tentatively applied to the reconstruction of the distribution of the surfactant with R = n-dodecyl and
= 7.1. The choice of the internal standard is discussed. 相似文献
986.
987.
Saturated and benzylic organomagnesium compounds are shown to readily undergo addition reactions with the conjugated enynes HCHCH2R′, with R′ = alkyl, OH, OC4H9, NHC25, N(C2H5)2, by refluxing for several hours in benzene or toluene.This reaction leads to both υ-acetylenic compounds (1,2-addition) and β-allenic compounds (1,4-addition). 相似文献
988.
Ohne Zusammenfassung 相似文献
989.
I. C. McNeill L. Ackerman S. N. Gupta M. Zulfiqar S. Zulfiqar 《Journal of polymer science. Part A, Polymer chemistry》1977,15(10):2381-2392
In the subambient thermal volatilization analysis (TVA) technique, degradation products initially at ?196°C are allowed to warm up to ambient temperature in a controlled manner under vacuum conditions, and volatilization from the sample tube to a trap at ?196°C is monitored by means of a Pirani gauge. The technique is discussed in relation to earlier TVA work in which volatilization from a heated polymer sample was followed. Design and operation of a subambient TVA system are described, and examples of the application of the technique to the study of the degradation products of seven polymers are considered. 相似文献
990.
R.R. Adžić D.N. Simić A.R. Despić D.M. Dražić 《Journal of Electroanalytical Chemistry》1975,65(2):587-601
It was demonstrated that some foreign metal monolayers formed by underpotential deposition have pronounced catalytic effects on the oxidation of formic acid on platinum. The explanation of these effects was sought within the framewor of existing data on the formic acid oxidation and the underpotential deposition. It was found that the catalytic effect of foreign metal monolayers originates in the decrease of hydrogen adsorption thus preventing the formation of the main poisoning species COH. At the same time these experiments confirm the previously postulated mechanism of formation of the poisoning species involving adsorbed hydrogen. 相似文献