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71.
Trombotto S Danel M Fitremann J Bouchu A Queneau Y 《The Journal of organic chemistry》2003,68(17):6672-6678
The base-catalyzed reaction of carboxymethyl 3,4,6-tri-O-acetyl-alpha-D-glucopyranoside 2-O-lactone (prepared from isomaltulose) with amino acids and fatty amines under basic catalysis gave a series of new pseudoglucopeptides, nonionic amphiphiles, and polymerizable derivatives. The same reaction applied to alcohols provided the corresponding 2-(alpha-D-glucopyranosyloxy)acetyl esters with either basic or acidic catalysts. 相似文献
72.
Laurent Salvi Hélène Cattey Yves Mugnier Antonio Otero 《Journal of organometallic chemistry》2004,689(22):3473-3480
Electrochemical reduction of niobocene dichloride (η5-C5H4SiMe3)2NbCl21 formulated as in the presence of 3,4-diaminobenzoic acid yields to the complex [Nb(η5-C5H4SiMe3)2(κ2-O,O-OOC(C6H3)(NH2)2)] 3. When CN(2,6-Me2C6H3) formulated as xylylisonitrile (CNXylyl) is added to a complex 3 solution, a substitution reaction takes place to lead to the complex [Nb(η5-C5H4SiMe3)2(κ1-O-OOC(C6H3)(NH2)2)(CN(2,6-Me2C6H3)) 4 after 3 h. An alternative way to yield quantitatively and nearly instantaneously 4 consists in a previous oxidation of 3 in the presence of CNXylyl. Hence, we present here a new example of electron-transfer-catalyzed (ETC) ligand substitution of carboxylato niobocene complex induced by electrochemical oxidation. The structure of the complexes, the formation mechanism are described using electrochemical and spectroscopic data. Electrochemical simulation have been done to verify experimental results and to complete them with a kinetic study. 相似文献
73.
The water exchange of [V(H2O)6]Cl2 in aqueous solution has been studied as a function of temperature and pressure (up to 250 MPa), by measuring the 17O-FT-NMR. line-widths of the free water resonance at 8.13 MHz. The kinetic parameters obtained are K = 87±4 s?1, ΔH* = +61.8 ± 0.7 kJ mo1?1 and ΔS* = ?0.4±1.9 J mol?1 K?1. A pressure-independent volume of activation ΔV* = ?4.1±0.1 cm3 mol?1 is obtained, suggesting an associative interchange (Ia) mechanism for this early divalent metal ion. 相似文献
74.
Yves Le Jan 《Comptes Rendus Mathematique》2012,350(13-14):643-646
We study the clusters defined by Poisson processes of Markov loops. 相似文献
75.
Yves Crama Michel Grabisch Silvano Martello 《4OR: A Quarterly Journal of Operations Research》2016,14(4):333-336
We recall some cases of ethical misconduct that occurred in the recent years, and we report a new trick that was recently attempted to cheat the journal in order to obtain the publication of an article through usurped identity. 相似文献
76.
77.
78.
Yves Diers 《代数通讯》2013,41(17-18):2141-2183
79.
Alain Comtet Jean-Marc Luck Christophe Texier Yves Tourigny 《Journal of statistical physics》2013,150(1):13-65
We study products of arbitrary random real 2×2 matrices that are close to the identity matrix. Using the Iwasawa decomposition of SL(2,?), we identify a continuum regime where the mean values and the covariances of the three Iwasawa parameters are simultaneously small. In this regime, the Lyapunov exponent of the product is shown to assume a scaling form. In the general case, the corresponding scaling function is expressed in terms of Gauss’ hypergeometric function. A number of particular cases are also considered, where the scaling function of the Lyapunov exponent involves other special functions (Airy, Bessel, Whittaker, elliptic). The general solution thus obtained allows us, among other things, to recover in a unified framework many results known previously from exactly solvable models of one-dimensional disordered systems. 相似文献
80.
In the canonical network model, the connections model, only three specific network structures are generically efficient: complete, empty, and star networks. This renders many plausible network structures inefficient. We show that requiring robustness with respect to stochastic information transmission failures rehabilitates incomplete, redundant network structures. Specifically, we show that star and complete networks are not generally robust to transmission failures, that circular and quasi-circular networks are efficient at intermediate costs in four-player networks, and that if either of them is efficient, then at least one of them is pairwise stable even without reallocation. Thus, incomplete, redundant networks are efficient and stable at intermediate costs. 相似文献