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L. Michaelis P. Rona S. P. L. sörensen S. Palitzsch und J. Grabowski 《Fresenius' Journal of Analytical Chemistry》1911,50(4-5):322-324
Ohne Zusammenfassung 相似文献
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The kinetics of the proton transfer between hydroxyl ions and phenylazoresorcinol, 4-(p-nitrophenylazo), and 4-(m-nitrophenylazo) resorcinol have been investigated at 25°C and an ionic strength of 0.1M, in a wider pH range than had been done by previous authors. The rate at first decreased with decreasing [OH?], reached a minimum, and then started to increase with decreasing [OH?]. This unusual effect is explained by a mechanism suggested earlier for tropaeolin O. Rate constants and equilibrium constants have been evaluated and discussed. The experimental data were obtained by the T-jump method. 相似文献
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The cycloaddition reaction of N-sulfinylanilines - serving as “dienes” — with aromatic Schiff bases provides a convenient access to the thiadiazine oxide system () 相似文献
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Nainamalai?Sitheswaran Nigel T.?Price Rona R.?RamsayEmail author 《Monatshefte für Chemie / Chemical Monthly》2005,136(8):1341-1347
Summary. The structure of carnitine acetyltransferase revealed a putative binding site for longer acyl chains but access was blocked by methionine 564 (G. Jogl and L. Tong (2003) Cell 112, 113–122). The equivalent residue in all long chain carnitine acyltransferases is a conserved glycine. Mutation of glycine 553 to methionine in bovine COT resulted in loss of activity with all acyl-CoA substrates except acetyl-CoA, supporting the hypothesis that the methionine blocks access for longer acyl chains. The kinetic characteristics of acetyl transfer to carnitine were identical in the native and mutant enzyme. However, rapid acetyl-CoA hydrolysis in the mutant but not the wild-type indicates perturbation of the catalytic site. 相似文献
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Bugoni L McGill RA Furness RW 《Rapid communications in mass spectrometry : RCM》2008,22(16):2457-2462
Increasing use is being made of stable isotopes as indicators of habitat use and trophic ecology of animals. Preservation of tissues can alter stable isotope signatures. We investigated the effects of addition of ethanol and NaCl solution (hereafter 'salt'), and of freezing and drying, on carbon and nitrogen isotopic values in blood of the spectacled petrel Procellaria conspicillata, and compared these with those from simultaneously growing feathers. The mean delta(13)C values of blood preserved in ethanol was significantly higher, and of blood preserved in salt was significantly lower than that of dried or frozen samples. delta(13)C values in ethanol showed high variation according to brand and batch and could account for the differences found in delta(13)C ratios in ethanol-preserved blood samples. Mean delta(13)C and delta(15)N values in growing feathers were higher than in blood, suggesting tissue-specific fractionation. We conclude that different methods of preserving tissues such as blood may bias stable isotope values, and urge researchers to consider this issue. Air drying is proposed as a practical and unbiased method for blood preservation in field situations where freezing is not a practical option, and a mathematical approach is suggested to permit comparison between studies using different preservation methods or tissues. 相似文献
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E. Abderhalden H. Fühner E. Letsche Otto Folin Peter Rona Hans Lohrisch E. F. Edelstein Kumagawa Leonor Michaelis Emil Fischer W. Autenrieth Hans Pringsheim Donald D. van Slyke Franz Müller Wilhelm Völtz Georg Lockemann A. B. Macallum Otto Neubauer Fritz Pregl J. Traube Ludwig Pincussohn 《Analytical and bioanalytical chemistry》1912,51(9):594-596