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991.
L. A. Shchukina R. G. Vdovina Yu. B. Shvetsov A. V. Karpova 《Russian Chemical Bulletin》1962,11(2):286-288
Summary A preparative method was developed for obtaining L-and D-2-hydroxy-3-methylbutyric acids by the separation of racemic 2-hydroxy-3-methylbutyric acid with the aid of D-and L-threo-2-amino-1-p-nitrophenyl-1,3-propanediols. 相似文献
992.
L. S. Andreeva A. A. Andrianov V. E. Bel'skii M. F. Vavilova É. A. Gurylev K. V. Nikonorov 《Russian Chemical Bulletin》1971,20(10):2219-2221
Conclusions The hydrolysis of chloroacetophos in water includes the parallel cleavage of acetic acid, hydrochloric acid and methanol. The ratio of the products, formed in the parallel steps, was determined, and we also determined the total rate constant for the hydrolysis of chloroacetophos.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2336–2338, October, 1971. 相似文献
993.
Powder X-ray diffraction study of sodium salts of 1-hydroxyethane-1'1-diphosphonic acid (H4L)of the compositions NaH3L·H2O, Na2H2L·4H2O, Na3HL·5.5H2O showed that these compounds aresingle-phase. Some of their properties were determined. The possibility of preparing salts of other compositionswas examined. 相似文献
994.
P. V. Snytnikov K. V. Yusenko S. V. Korenev Yu. V. Shubin V. A. Sobyanin 《Kinetics and Catalysis》2007,48(2):276-281
The performance of a Co-Pt powder and of Co-Pt catalysts supported on γ-Al2O3 and on the graphite-like carbon material Sibunit in selective CO oxidation in hydrogen-containing mixtures is considered. Fine particles of metal-metal solid solutions and intermetallides were obtained by the decomposition of a Co- and Pt-containing double complex salt in a hydrogen atmosphere at ~400°C. As compared to their Pt and Co monometallic counterparts, the bimetallic catalysts are more active and allow the CO concentration in hydrogen-containing mixtures to be reduced from 1 to 10?3 vol %. This effect is likely due to the formation of bimetallic particles of a Co-Pt solid solution on the support surface. 相似文献
995.
A rapid and selective method has been developed for the determination of cadmium in environmental samples by thermal neutron activation analysis, employing substoichiometric solvent extraction technique. Alcoholic solution of 2-mercaptobenzothiazole /2-HMBT/ has been used for the substoichiometric extraction of Cd/II/ from an aqueous solution of pH 7.0 into methyl iso-butyl ketone /MIBK/. 相似文献
996.
The reaction between cumene hydroperoxide (CHP) and anhydrous hydrogen chloride under various conditions of temperature and concentration has been studied in an inert solvent (chlorobenzene) and in an oxidisable medium (cumene). The kinetics were first order with respect to each reactant; the energy of activation of the overall second-order reaction was 53.4 kJ mol?1 K?1. Competing ionic and free radical mechanisms were found to operate, the latter predominating at relatively high HCl concentrations, leading to rapid pro-oxidation in cumene. The effect of typical organo-tin PVC stabilizers on the pro-oxidant process were examined. It was found that dibutyltin maleate neutralized the HCl thus eliminating the pro-oxidant effect when used in stoichiometric proportions, but had little other effect. Dioctyltin bis(isol-octylthioglycollate) on the other hand not only neutralized the HCl stoichiometrically but gave additional oxidative stabilization over a wide concentration range. 相似文献
997.
998.
A. V. Eremeev V. G. Andrianov I. P. Piskunova 《Chemistry of Heterocyclic Compounds》1978,14(9):963-966
The reaction of some linear and cyclic -keto esters with 3,4-diaminofurazan was investigated. Products of condensation at the keto group and the corresponding furazanodiazepinones were isolated and characterized. The structures of the compounds obtained are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1196–1199, September, 1978. 相似文献
999.
1000.