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971.
Conclusions We synthesized two analogs of the natural coenzyme adenosine diphosphate glucose: N6-methyl-ADPG and N6, N6-dimethyl-ADPG.For communication 11, see [1].The following abbreviations are used in this article: ADPG) adenosine-5'-diphosphate-a-D-glucopyranose; N6-methyl-ADPG) N6-methylamino-9--D-ribofuranosylpurine-5-diphosphate--D-glucopyranose; N6, N6-dimethyl-ADPG) N6, Ng-dimethylamino-9--D-ribofuranosylpurine-5-diphosphate--D-glucopyranose.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2514–2521, November, 1969.  相似文献   
972.
973.
The adsorption of thorium(IV) ions on molecular sieve (13X type) powder from aqueous solutions has been studied as a function of shaking time pH, thorium ion concentration and temperature. The conditions of maximum adsorption of thorium ions obeys Langmuir and D-R isotherms over the entire concentration range studied. Thermodynamic quantities such as H, G and S have been calculated fromK D values determined at various temperatures. The results show endothermic heat of adsorption, but negative free energy value indicates that the process of thorium adsorption on molecular sieve powder is favored at high temperature. The influence of various cations and anions on thorium(IV) ion adsorption was examined. A wavelength dispersive X-ray fluorescence spectrometer was used for measuring the thorium ion concentration in solutions.  相似文献   
974.
975.
Conclusions The previously unknown chromium -arenecarbonyl complexes containing -pyrrolylmanganesetricarbonyl as a two-electron ligand, C6H6Cr(CO)2NC4H4Mn(CO)3, Me3C6H3Cr(CO)2NC4H4Mn(CO)3, and PhCOOMeCr(CO)2NC4H4Mn(CO)3, have been synthesized and characterized by spectroscopic methods.For Communication 6, see [6].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2780–2782, December, 1985.  相似文献   
976.
The molecular geometries of a series of steroid hormones including cortisol, 9-fluorocortisol, 6-fluorocortisol, and 9-chlorocortisol were optimized by 3-21G and 6-31G* ab initio calculations. The results of calculations on both levels are well consistent with each other and with the experiment. The conformational changes and electron density redistribution occurring in going from cortisol to its 6- and 9-halo derivatives were discussed. A conclusion was made that the O and F atoms can participate in hydrogen bonding with the corresponding structural groups of glucocorticoid receptors.  相似文献   
977.
The transport of water molecules and the distribution of functional groups in polyamidoacid carboxyl-containing cation-exchange membranes based on pyromellitic acid are studied by NMR and ESR techniques. It is shown that the self-diffusion coefficients of water differ in the gel and intergel regions. Structural parameters of conducting channels in the gel regions are determined. In electrodialysis of one-component and binary solutions, polyamidoacid membranes possess higher transport numbers and separation coefficients of counterions that are less hydrated in solution.  相似文献   
978.
Barrier-discharge plasma treatment of real surface water to remove organic pollutants was studied. Plasma treatment decreases the potential toxicity of snowmelt and rainfall runoff containing ammonium and chloride ions, oil products, phenols, and carboxylic acids (as recalculated for CH3COOH).  相似文献   
979.
Zusammenfassung Aus polychlorierten Kaliumxanthogenaten wurden verschiedene Metall-Chelate dargestellt, dünnschicht-chromatographisch getrennt und ihre Rf-Werte unter verschiedenen Trennbedingungen bestimmt.Anschließend wurden die einzelnen Komplexe gas-chromatographisch mit Elektroneneinfang-Detektoren untersucht. Über den durch augenblickliche thermische Zersetzung des Chelats in reproduzierbarer Menge anfallenden polychlorierten Alkohol konnten Metalle im ng-Bereich quantitativ indirekt bestimmt werden.
Polychlorinated compounds and their use for the gas-chromatographic determination of elements in the ng-rangeI. Polychlorinated xanthates and their use for the determination of nickel
Ten chelates of polychlorinated xanthates were investigated by thin-layer chromatography. Their Rf-values were determined on silica gel and aluminium oxide for several different eluents. At 200° C the xanthates pyrolize momentarily and reproducibly to the corresponding alcohol, allowing the perchlorinated ligands to be utilized for the determination of metals by electron capture gas-chromatography.Combining thin-layer chromatography and the pyrolyzing technique nanogram amounts of mixtures of metals can be determined.


Die Arbeit wurde in dankenswerter Weise von der Deutschen Forschungsgemeinschaft, Bad Godesberg, der Fazitstiftung, Gemeinnützige Verlagsgesellschaft m. b. H, Frankfurt a. M., und dem Verband der Chemischen Industrie e.V., Düsseldorf, unterstützt.  相似文献   
980.
Nonfused bis-1,3,4-oxadiazoles were synthesized by reaction of 5-substituted mono-and bis-tetrazoles with mono-and dicarboxylic acid chlorides. The results of kinetic studies showed that the transformation of tetrazoles into 1,3,4-oxadiazoles is accelerated by 1 to 2 orders of magnitude on addition of a catalytic amount of dimethylformamide, triethylamine, or pyridine.  相似文献   
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