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991.
V. A. Kaganovskii T. F. Makovskaya V. M. Chertov 《Theoretical and Experimental Chemistry》1994,30(2):78-80
A study has been made of the effect of combining tetraethoxysilane hydrolysis and polycondensation catalysts operating by different mechanisms on the texture parameters of synthesized silica gels. The effect of hydrothermal treatment of a fluorine-containing silica hydrogel on the thermal stability of the xerogel texture was demonstrated.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 30, No. 2, pp. 95–98, March–April, 1994. 相似文献
992.
993.
994.
N. A. Davidenko Yu. P. Get’manchuk M. A. Zabolotnyi T. G. Zabolotnaya L. P. Linets E. V. Mokrinskaya V. A. Pavlov S. L. Studzinskii N. G. Chuprina 《High Energy Chemistry》2006,40(6):410-416
The effect of doping with CdS nanoparticles of recording medium films for the thermoplastic holographic recording process, which are based on photosemiconductors (oligomers and cooligomers of glycidylcarbazole) and a dielectric (a styrene copolymer with octyl methacrylate) containing a photoconductivity sensitizer, on their photosensitivity was studied. The enhancement of photosensitivity of films by doping with nanoparticles is associated with the appearance of an additional channel for transport of electrons generated from sensitizer molecules. A difference in informational properties between the oligomer and the polymer films was revealed. 相似文献
995.
T. T. Kucherenko P. V. Muzyka É. B. Rusanov A. N. Chernega V. A. Kovtunenko A. K. Tyltin F. S. Babichev 《Chemistry of Heterocyclic Compounds》1992,28(5):515-518
An unusual path for the reaction of 2-aryl-1-dimethylamino-2H-isoindoles with N-R-maleimides, leading to the imides of l,2-dihydronaphthalene-2,3-dicarboxylic adds, was established by x-ray crystallographic analysis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 614–618, May, 1992 相似文献
996.
997.
The crystal structure of 12,13-dibromopseurotin has been determined by single crystal X-ray analysis. The crystals belong to space group P21 with a = 16.75, b = 9.63, c = 7.42 Å, β 95.9°, Z = 2. The structure was solved by the heavy atom technique and refined to R = 0.062 with 819 significant reflexions for 299 parameters. 相似文献
998.
Results are reported for the kinetics of the anionic polymerization of ethylene oxide in hexamethylphosphoramide using the caesium alkoxide of the monoethylether of diethylene glycol as initiator at 40·0°.The reactions were found to be first order in monomer and 0·5 in initiator; rates are depressed by adding caesium tetraphenyl boride. These results indicate that propagation takes place by free ions and ion pairs; the respective propagation rate constants are k(?) = 22 and k(±) = 0·2 M 'sec. 相似文献
999.
A procedure has been developed which allows for the isolation, collection and analysis of atmospheric gaseous iodine and bromine. Particulate matter is removed from the airstream to be sampled by electrostatic precipitation. The gaseous halogen species are adsorbed onto specially cleaned activated charcoal. After irradiation of the charcoal sample with thermal neutrons, the iodine and bromine are removed from the charcoal, isolated, and purified as the AgX precipitate. The amounts of gaseous iodine and bromine are then determined by β-counting. The system works well for air sheds with low particulate iodine and bromine concentrations relative to that in the gaseous phase. In air sheds where the particulate halogen predominates, the gas phase measurements are more uncertain. 相似文献
1000.
Clifford J. M. Smyth M. R. Smyth W. Franklin 《Analytical and bioanalytical chemistry》1974,270(3):198-200
Analytical and Bioanalytical Chemistry - A combination of differential solvent extraction based on physical chemical properties of the species involved and differential pulse polarography has been... 相似文献