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911.
T. V. Rybalova V. F. Sedova Yu. V. Gatilov O. P. Shkurko 《Chemistry of Heterocyclic Compounds》1998,34(10):1161-1165
The crystal structure of 2-nitropyridine has been determined by x-ray diffraction analysis. The influence of the nitro group
on the geometric parameters of the molecule was evaluated, as well as its influence on the molecular parameters of other nitropyridines,
depending on the position of this group in the pyridine ring.
Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090. E-mail:
gatilov@nioch.nsc.ru. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1367–1371, October, 1998. 相似文献
912.
The simple determination of the sum of weak (polycarboxylic) acids in aqueous solutions and titratable acidity of wines based on indirect iodate-iodide potentiometry without titration was described. 相似文献
913.
O. A. Luk'yanov V. P. Gorelik V. A. Tartakovskii S. S. Novikov 《Russian Chemical Bulletin》1971,20(8):1696-1697
Conclusions The nitration of the sodium salts of sulfamides with nitrogen pentoxide leads to the formation of the corresponding N-nitrosulfamides.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1804–1806, August, 1971. 相似文献
914.
D. B. Furman N. V. Volchkov L. S. Isaeva L. N. Morozova D. N. Kravtsov O. V. Bragin 《Russian Chemical Bulletin》1988,37(11):2220-2222
Conclusions By studying the liquid-phase dimerization of ethylene in the presence of Cat-Et3Al2-Cl3 catalytic systems based on a nickel complex heterogenized on Al2O3 and a number of model nickel complexes, a similar activity and selectivity of the process has been established (Cat=NiPPh3(CO)2L, where L=PPh3, CO, Al2O3; Ni(PPh3)2(CO)2; Ni(PPh3)2(2-C2H4); Ni[P(C6H11)3]2(H)Cl and Ni(PPh3)(Et)Cl).The results of the investigation agree with the hypothesis that mono- and diolefinic nickel complexes are formed as the active intermediates in the reaction.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2466–2469, November, 1988. 相似文献
915.
The structures of the essential metabolites which are excreted by the rat after oral application of GS 13005 (O,O-dimethyl-S-[(2-methoxy-1,3,4-thiadiazole-5(4H)-one-4-yl)-methyl] dithiophosphate) have been elucidated. The product of final oxidation, CO2, was found to be the main metabolite (up to 36% of the dose applied). Among the degradation products excreted in the urine (up to 45% of the dose applied) the two most important were isolated. They are 4-methylsulfinylmethyl and 4-methylsulfonylmethyl derivatives respectively of the intact 2-methoxy-1,3,4-thiadiazole-5-one heterocycle (metabolites III and II, in amounts of 20–25% and 5–7% of the dose applied, respectively). These metabolites originate by methylation and subsequent oxidation from the mercaptomethyl derivative liberated after hydrolysis of the P S bond of the dithiophosphoric acid ester. 相似文献
916.
A. A. Yamontaite G. K. Krasil'nikova O. V. Kil'disheva I. L. Knunyants 《Chemistry of Heterocyclic Compounds》1972,8(4):436-439
The ethyleneimides of N-phthalyl-D,L-valine, N-phthalyl-D,L-glycine, N-phthalyl-D,L-alanine, N-carbobenzoxy-D,L-valine, N-benzoyl-D,L-leucine, and of the -methyl ester of N-carbobenzoxy-L-glutamic acid and monomethyl succinate were synthesized. A number of O,O-diethyl S-(-acrylaminoethyl) dithiophosphates were obtained by opening the ethyleneimine ring in the ethyleneimides of N-acylated amino acids with diethyl dithiophosphoric acid. The -chloroethylamides of phthalyl-D,L-valine, N-acetyl-D,L-valine, and monomethyl succinate were obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 479–482, April, 1972. 相似文献
917.
V. O. Yablonskii 《Russian Journal of Applied Chemistry》2005,78(8):1294-1300
The model of separation of suspensions with a non-Newtonian dispersion medium in a cylindroconical hydrocyclone, which takes into account the effect of the Coriolis force on solid particles, was constructed and applied to analysis of the rheological properties of the dispersion medium on separation of suspensions in hydrocyclones with various working space configurations. 相似文献
918.
A D C, spectrochemical method using the STALLWOOD jet has been developed for the determination of Li, Na, K and Rb in silicate minerals and rocks. Samples are mixed with graphite and Cs2CO3 in tho ratio 2 : 1 : 1, and Cs serves as internal standard. Precision and accuracy is satisfactory. 相似文献
919.
Lamberov A. A. Levin O. V. Egorova S. R. Evstyagin D. A. Aptikasheva A. G. 《Russian Journal of Applied Chemistry》2003,76(3):351-357
The method of low-temperature adsorption of nitrogen was applied to study structural characteristics of commercial peptized aluminum hydroxides. An increase or decrease in the porometric volume, depending on the nature and concentration of the peptizing agent, was analyzed. The phenomena observed are explained in terms of the mechanism suggested for formation of the pore system in commercial aluminum hydroxides. The dependence of the physicomechanical properties of active aluminum oxide on synthesis conditions and texture characteristics of commercial aluminum hydroxides was studied. 相似文献
920.
We have established a luminol- and a lucigenin-dependent CL methods to investigate the role of the receptors for Fc portion of IgG (FcgammaR) and/or complement receptors (CR) in mediating the oxidative burst in neutrophils from systemic lupus erythematosus (SLE) patients compared with healthy controls. In the luminol-CL system, all the reactive oxygen species (ROS) are responsible for light production, whereas in the lucigenin-CL system, only the first ROS generated, converts the lucigenin into an unstable intermediate molecule, which also emits light. First, neutrophils from healthy controls and SLE patients were stimulated with different IC opsonized or not with complement from normal human serum (NHS) or SLE serum, in presence of 10(-4) M luminol. This method was able to differentiate the role of the FcgammaR, CR and FcgammaR/CR co-operation in mediating the oxidative burst, as well as show that the oxidative burst mediated by these receptors was reduced in neutrophils from SLE patients. Second, neutrophils from healthy controls and SLE patients were stimulated with different IC, opsonized or not with NHS, in presence of 10(-3) M lucigenin. In this case, the lucigenin-CL system was also able to differentiate the role of FcgammaR and FcgammaR/CR co-operation, as well as show differences among healthy controls and two different groups of SLE patients according to their clinical manifestations. In conclusion, we have established two sensitive CL systems to study the role of FcgammaR and/or CR in stimulating the oxidative burst of neutrophils, which can be applied in monitoring the involvement of these receptors in the immunopathogenesis of SLE. 相似文献