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991.
992.
993.
Theodore S. Prokopov 《Mikrochimica acta》1970,58(4):694-701
Summary A non-sulfide scheme of inorganic qualitative microanalysis is presented with solutions of HCl, CH3COONa, H2SO4, and NaOH as group reagents. Color reactions (spot tests) are also included in this scheme. The purpose of this new approach to qualitative analysis is to eliminate disagreeable odor and corosive action of hydrogen sulfide as also to introduce complete group separations leading to more definite analytical results.
Zusammenfassung Ein Schema für die qualitative anorganische Analyse ohne Schwefelwasserstoff mit Salzsäure, Na-Acetat, Schwefelsäure und Natronlauge als Gruppenreagenzien wird vorgelegt. Farbreaktionen (Tüpfelproben) werden im Laufe des Analysenganges verwendet. Die Geruchsbelästigung und die Korrosion durch Schwefelwasserstoff wird vermieden und gleichzeitig eine Gruppentrennung mit eindeutigeren Ergebnissen erzielt.相似文献
994.
995.
N. K. Gusarova N. A. Chernysheva M. Ya. Khil'ko S. V. Yas'ko L. M. Sinegovskaya N. N. Chipanina N. A. Korchevin B. A. Trofimov 《Russian Journal of General Chemistry》2005,75(8):1247-1250
Selective monoaddition of carbonodithioate anions to divinyl sulfoxide gives rise to O-alkyl S-[2-(vinylsulfinyl)ethyl] carbonodithioates [ROC(S)SK, R = Et, Bu; 42–50°C, 6 h, NaHCO3, aqueous benzene]. 相似文献
996.
N. S. Shaglaeva O. V. Lebedeva Yu. N. Pozhidaev R. G. Sultangareev S. S. Bochkareva L. A. Es’kova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(3):335-338
Hybrid organoinorganic composites insoluble in water and organic solvents were prepared by the hydrolysis of tetraethoxysilane in the presence of poly-1-vinylpyrazole, poly-1-vinylimidazole, and poly-4-vinylpyridine. The composition of the composites was determined by the nature of the polymeric nitrogen base and hydrolysis conditions. The composites synthesized showed high sorption activity in the extraction of the [PdCl4]2?, [PtCl6]2?, and [AuCl4]? ions from hydrochloric acid solutions. 相似文献
997.
The conjugate of mitomycin C (MMC) with linear (1----3)-beta-D-glucan from Alcaligenes faecalis var. myxogenes IFO 13140 was synthesized and its antitumor activities investigated. The conjugate (MMC-carboxymethylated linear (1----3)-beta-D-glucan (CMPS)) was obtained by treatment of CMPS with MMC in the presence of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide. In vitro cytotoxicity of MMC-CMPS against L1210 leukemia cells was similar to that of MMC. In i.p.-i.p. system in vivo against P388 leukemia in mice, the maximum increase of MMC-CMPS conjugate in life span (ILSmax) was higher than that of MMC but the therapeutic index was reduced. However, the antitumor activity of MMC-CMPS conjugate against subcutaneously implanted sarcoma 180 solid tumor in mice by i.p. administration was similar to that of MMC at a dose of 1.5 mg eq MMC/kg/d x 7 and the reduction of the number of leukocytes caused by MMC was suppressed by attaching MMC to CMPS. In addition, on assay using serum of sarcoma 180 solid tumor-bearing mice with injection of MMC-CMPS conjugate, a drastic loss of tumor cells and an increase in polymorphonuclear leukocytes (PMN) were observed. This result suggested that MMC-CMPS conjugate induced tumor-regressing factor similar to CMPS. 相似文献
998.
M. Zh. Ovakimyan S. K. Barsegyan A. S. Pogosyan N. M. Kikoyan M. G. Indzhikyan 《Russian Journal of General Chemistry》2006,76(11):1757-1759
Dehydrogenation of 1-(diphenylphosphinoyl)-2-hydrazino-substituted ethanes and N-butyl-N′-phenylhydrazine to the corresponding hydrazone derivatives is performed. Both reactions were established to involve predominantly, if not exclusively, an azo intermediate. 相似文献
999.
Serber Z Ledwidge R Miller SM Dötsch V 《Journal of the American Chemical Society》2001,123(37):8895-8901
Our recently developed in-cell NMR procedure now enables one to observe protein conformations inside living cells. Optimization of the technique demonstrates that distinguishing the signals produced by a single protein species depends critically on protein overexpression levels and the correlation time in the cytoplasm. Less relevant is the selective incorporation of (15)N. Poorly expressed proteins, insoluble proteins, and proteins that cannot tumble freely due to associations within the cell cannot yet be observed. We show in-cell NMR spectra of bacterial NmerA and human calmodulin and discuss limitations of the technique as well as prospects for future applications. 相似文献
1000.