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991.
992.
T. Sato F. Ambe K. Endo M. Katada H. Sano 《Journal of Radioanalytical and Nuclear Chemistry》1995,190(2):257-261
The crystal structures of oxo-centered trineclear cobalt-iron chloroacetate complex [CoIIFe
2
III
O(CH2ClCO2)6(H2O)3]·3H2O (1) was compared with that of previously reported trinuclear iron complex [FeIIFe
2
III
O(CH2ClCO2)6(H2O)3]·3H2O (2) which has an isomorphous structure to 1. Compound 1 crystallizes in space group P21/n with Z=4 in a unit cell of a=14.826 (4) Å, b=4.536 (8) Å, c=14.000 (4) Å, =100.32 (2)0 and V=2968 (11) Å3. The structure was refined to R=0.75 and Rw=0.82. The coordination geometries of the three iron atoms are observed equivalent in 1 indicating a static disorder of the position among cobalt and iron atoms. Two distinct FeIII doublets observed in Mössbauer spectra of 1 become an indistinguishable broad doublet by dehydration of crystal water. On the other hand, no significant line-broadening is observed after the dehydration in complex 2. The results indicate that the dehydration in 2 induces a local environmental change reordering of an electronic configuration around iron atoms, whereas the remaining disordering is reflected in Mössbauer spectrum after the dehydration in 1. 相似文献
993.
994.
Conclusions Primary amino alcohols react with CO in the presence of mercuric acetate at 100–200° and a pressure of 100–150 atm to give the corresponding N-(hydroxyalkyl)formamides in a yield of 1.4–2.5 M/M of reacted Hg(OCOCH2)3. Morpholine under analogous conditions forms the corresponding formyl derivative and the urea derivative in a 1.2–51 ratio, while cyclohexylamine forms the same derivatives in an 0.7 1 ratio.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1533–1536, July, 1973. 相似文献
995.
996.
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
997.
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
998.
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
999.
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
1000.
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