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91.
Wojciech Szymanski Shuang Zhang 《Proceedings of the American Mathematical Society》2000,128(3):813-818
Let be a free product of at least two but at most countably many cyclic groups. With each such group we associate a family of C*-algebras, denoted and generated by the reduced group C*-algebra and a collection of projections onto the -spaces over certain subsets of . We determine , the weak closure of in , and use this result to show that many of the C*-algebras in question are non-nuclear.
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Tomasz Goslinski Zbigniew Dutkiewicz Michal Kryjewski Ewa Tykarska Lukasz Sobotta Wojciech Szczolko Maria Gdaniec Jadwiga Mielcarek 《Monatshefte für Chemie / Chemical Monthly》2011,13(1):599-608
Abstract
An earlier developed alkylating path leading to tetraalkylated diaminomaleonitrile derivatives was explored. Attempts to explain the reactivity of the representative dialkylated diaminomaleonitrile 2,3-bis[(3-pyridylmethyl)amino]-2(Z)-butene-1,4-dinitrile during the alkylation reaction were performed using X-ray and density functional theory (DFT) studies. The condensed Fukui functions accompanied by softness indices were found to be useful in explaining its reactivity observed during the reaction. The values of the Fukui functions and condensed softness for electrophilic attack calculated from Mulliken, L?wdin, and natural population analyses closely corresponded to the experimental observations. When 2,3-bis[(3-pyridylmethyl)amino]-2(Z)-butene-1,4-dinitrile disodium salt was treated with dimethyl sulfate at lower temperatures the alkylation reaction prevailed, whereas at higher temperatures the alkylating agent acted as a hydride anion acceptor, which favored the elimination reaction. The tetraalkylated dinitrile 2,3-bis[methyl(3-pyridylmethyl)amino]-2(Z)-butene-1,4-dinitrile was used in the synthesis of tribenzoporphyrazine bearing methyl(3-pyridylmethyl)amino groups, which was subsequently subjected to solvatochromic and metallation studies. The changes observed during metallation seem to result from the coordination of the 3-pyridyl group by a palladium ion. This could influence the configuration of the methyl(3-pyridylmethyl)amino moiety, causing more effective donation of a lone pair of electrons from peripheral nitrogen to the macrocyclic ring. 相似文献95.
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It is shown that the empirical pseudo-second order kinetic equation is a very efficient formula to correlate the kinetic data
generated by applying theoretical expressions developed from the fundamental SRT (Statistical Rate Theory) approach to the
interfacial transport. This is especially true when the most popular linear representation is used in which time/adsorbed
amount is plotted vs. time. However, the commonly observed goodness of such linear plots does not necessarily speak for the
applicability of the pseudo-second order kinetic equation. A reliable estimation, for instance, of the equilibrium adsorbed
amount is possible only when a substantial part of a kinetic isotherms corresponds to the conditions close to equilibrium.
Energetic surface heterogeneity increases the goodness of these linear regressions. Then, experimental errors have only little
effect on the pseudo-second linear plots.
This article is dedicated to Professor Mietek Jaroniec on the occasion of his 60th birthday. 相似文献
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