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991.
Ohne Zusammenfassung 相似文献
992.
Lehmann und Zehntel-Normalrhodan-ammonlösung 《Fresenius' Journal of Analytical Chemistry》1901,40(2):136
Ohne Zusammenfassung 相似文献
993.
994.
Maria Edeleva Sylvain R. A. Marque Denis Bertin Didier Gigmes Yohann Guillaneuf Sergey V. Morozov Elena G. Bagryanskaya 《Journal of polymer science. Part A, Polymer chemistry》2008,46(20):6828-6842
In a recent article, we have showed that the nitroxide mediated polymerization of methyl methacrylate was possible up to 80% conversion for reasonable masses Mn = 60,000 g mol?1 when 2,2‐diphenyl‐3‐phenylimino‐2,3‐dihydroindol‐1‐yloxyl nitroxide (DPAIO) was used as control agent. We have claimed that the success of this experiment relied on the absence of H‐transfer reaction both in the alkoxyamine and between alkyl and nitroxyl radical. In this article, the decomposition of 4‐nitrophenyl 2‐(2,2,6,6‐tetramethylpiperidine‐1‐yloxy)‐2‐methylpropionate ( 1a ) and 4‐nitrophenyl 2‐(2,2‐diphenyl‐3‐phenylimino‐2,3‐dihydroindol‐1‐yloxy)‐2‐methylpropanoate ( 2a ) has been studied by 1H NMR in the presence and in the absence (persistent radical effect condition) of scavenger (thiophenol PhSH). At temperature lower than the one used for polymerization, fast and quantitative H‐transfer reaction was observed for 1a whereas no H‐transfer reaction was observed for 2a . The scavenging technique proved for the first time that the H‐transfer was an intermolecular process for 1a . However, the slow side‐reaction of N? OC bond homolysis, which did not impede the control of the polymerization but may exert a detrimental effect on the livingness, was observed and quantified for 2a . © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6828–6842, 2008 相似文献
995.
996.
997.
The efficient and original palladium-catalyzed amination of 5-Aryl-1,2,4-triazines and 1,2,4,5-tetrazines is reported. This Buchwald-Hartwig type reaction leads to the formation of aminated heterocycles via methylsulfur release. The reaction is optimized and a wide range of amines is used to determine the scope and limitations of this methodology. 相似文献
998.
Antonio Celani Sylvain Rubenthaler Dario Vincenzi 《Journal of statistical physics》2010,138(4-5):579-597
The dynamics of fluid particles on cylindrical manifolds is investigated. The velocity field is obtained by generalizing the isotropic Kraichnan ensemble, and is therefore Gaussian and decorrelated in time. The degree of compressibility is such that when the radius of the cylinder tends to infinity the fluid particles separate in an explosive way. Nevertheless, when the radius is finite the transition probability of the two-particle separation converges to an invariant measure. This behavior is due to the large-scale compressibility generated by the compactification of one dimension of the space. 相似文献
999.
The aim of this paper is to study the behavior of Hodge‐theoretic (intersection homology) genera and their associated characteristic classes under proper morphisms of complex algebraic varieties. We obtain formulae that relate (parametrized families of) global invariants of a complex algebraic variety X to such invariants of singularities of proper algebraic maps defined on X. Such formulae severely constrain, both topologically and analytically, the singularities of complex maps, even between smooth varieties. Similar results were announced by the first and third author in [13, 32]. © 2007 Wiley Periodicals, Inc. 相似文献
1000.
K. B. Lehmann C. Nussbaum R. Emmerich G. Markl G. de Rossi und F. Ballner 《Fresenius' Journal of Analytical Chemistry》1902,41(5):324-326
Ohne Zusammenfassung 相似文献