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991.
The kinetics of formation of palladium dimethylglyoximate in the post-nucleation and pre-nucleation stages, and the effect of palladium on the reaction of biacetyl and hydroxylamine, have been studied. 相似文献
992.
James P. Kutney Eugene Dimitriadis Gary M. Hewitt Philip J. Salisbury Mahatam Singh James A. Servizi Dennis W. Martens Robert W. Gordon 《Helvetica chimica acta》1983,66(3):921-928
A detailed study of the biodegradation of one of the fish toxic chlorinated resin acids, 12,14-dichlorodehydroabietic acid 1 The correct IUPAC-name is 12,14-dichloro-8,9,11,12-tetradehydro-7,8-dihydroabietic acid. ( 3 ) is presented. When exposed to the fungus Mortierella isabellina, 3 is converted into a number of hydroxylated and keto derivatives which show low levels of toxicity to fish. These metabolites were isolated and characterized. 相似文献
993.
The ability of four semi-empirical methods to predict geometries of molecules containing atoms in the second row of the periodic table is investigated for about 80 molecules. Non-empirical, minimal basis set calculations, with and without optimization of valence orbital exponents, are carried out for a number of diatomic molecules. While none of the methods are capable of predicting geometries with an accuracy comparable to the first row parametrization, the SPD' method of Santry and the related INDO method of Benson and Hudson appear to be the most consistent. The ab initio calculations do not suffer from the drawbacks exhibited by the latter two semi-empirical methods. From this it is concluded that the failure of such methods lies in the parametrization rather than in the use of a minimal basis set. 相似文献
994.
995.
E.M. Gordon Jelka Pluščec N.G. Delaney S. Natarajan J. Sundeen 《Tetrahedron letters》1984,25(31):3277-3280
Amino acid derived chloromethyl ketones are shown to undergo a general dehydrohalogenation reaction under mild, basic, nonnucleophilic conditions to afford α-β-unsaturated ketones. 相似文献
996.
997.
L. G. M. Gordon 《Foundations of Physics》1983,13(10):989-997
A particle of molecular dimensions which can exist in two states is associated with a membrane pore through which molecules of a gas can pass. The gas molecules from two identical phases on either side of the membrane may pass only when the particle is in one particular state. If certain restrictions are imposed on the system, then the particle appears to act like a Maxwell's Demon(1) which “handles” the gas molecules during their passage through the pore. 相似文献
998.
Gordon M Fisher 《Historia Mathematica》1978,5(3):313-331
We consider Cauchy's use of the infinitely small in his textbooks. He never examined fully his concept of variables with limit zero, and he sometimes argued as if he were using actual infinitesimals. Occasionally he adopted an epsilon-delta approach. The author argues that historical evaluations of mathematical analysis may and should be made in the light of both standard and non-standard analysis. From this point of view, Cauchy's move toward founding analysis entirely on the standard real number system does not seem to have been inevitable. Some historical observations by the founder of non-standard analysis, Abraham Robinson, are extended, and in one case contested. It is shown that some of Cauchy's alleged errors are explained if he is admitted to have been thinking of actual infinitesimals and infinitely large integers. Cauchy's definitions of differential in his textbooks are examined, and the author shows that the earlier of his two definitions of total differential works well, but the later does not. 相似文献
999.
Gordon E. Swaters 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1994,45(4):638-657
It is qualitatively known that the gravest mode associated with a vertical normal-mode decomposition of a stationary, baroclinic modon in a continuously-stratified fluid of finite depth on a -plane necessarily contains an exterior downstream Rossby wave field if the background zonal flow is eastward. An. exact solution is presented describing this situation which satisfies the correct upstream no-waves constraint. 相似文献
1000.