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101.
Russian Chemical Bulletin - 相似文献
102.
Dr. Geno Kynast 《Analytical and bioanalytical chemistry》1971,256(1):20-24
A computer program for direct evaluation of thin-layer chromatograms, which already was described earlier [3] has been tested with a laboratory and some technical formulations of a pesticide. Results have been compared with those obtained by two conventional methods. Mean relative standard deviation calculated from results compiled by electronic data processing (method A) is about 6%, compared to 10% received by graphic method (method C) which is employed by most investigators. In addition, overall time of analysis is 34% higher if graphic method is used. Method A saves time and expense especially in routine analysis because working of the process is easier and may be performed even by assistent personal. The proposed method is suitable for the determination of different active ingredients and impurities even in difficult technical products. 相似文献
103.
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105.
Zelenin K. N. Verbov V. N. Matveeva Z. M. 《Chemistry of Heterocyclic Compounds》1977,13(12):1324-1327
It follows from the PMR spectra that the reaction of 1-methyl-, 1-phenyl-, 1-ethyl-,1-phenyl-, and 1,1-diphenyldiazenium salts with cis- and trans-d-styrenes, which leads to the corresponding 3-d-4-phenyl-1,2,3,4-tetrahydrocinnolines, takes place with retention of the configuration in the starting styrenes. It is therefore proposed that this reaction be regarded as a special case of [4+s + 2s]-cycloaddition.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1658–1661, December, 1977. 相似文献
106.
The application of internal reflection spectroscopy to the study of interface boundary layers has been extended over cases in which unstable particles appear at the interface as a result of imposing a negative electrical potential on the germanium hemicylinder, used simultaneously as an optical prism in the internal reflection spectroscopic device and as an electrode. The appearance of the particles is detected by their internal reflection spectrum. The method has been applied in the case of the electrochemically induced polymerization of acrylonitrile. Two particles were found to be generated during electrolysis. They are assigned to the anionradical and to the di-anion of acrylonitrile. 相似文献
107.
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109.
Rakhimkhanov Z. B. Sadykov A. S. Ismailov A. I. Karimdzhanov A. K. 《Chemistry of Natural Compounds》1970,6(1):124-124
Chemistry of Natural Compounds - 相似文献
110.