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排序方式: 共有3016条查询结果,搜索用时 15 毫秒
81.
Bimetallic Gold(I) Complexes with Ethynyl‐Helicene and Bis‐Phosphole Ligands: Understanding the Role of Aurophilic Interactions in their Chiroptical Properties
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![点击此处可从《Chemistry (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dr. Mehdi El Sayed Moussa Dr. Hui Chen Zuoyong Wang Dr. Monika Srebro‐Hooper Dr. Nicolas Vanthuyne Dr. Soizic Chevance Prof. Christian Roussel Prof. J. A. Gareth Williams Prof. Jochen Autschbach Prof. Régis Réau Prof. Zheng Duan Dr. Christophe Lescop Dr. Jeanne Crassous 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(17):6075-6086
Monometallic gold(I)‐alkynyl‐helicene complexes ( 1 a , b ) and bimetallic gold(I)‐alkynyl‐helicene architectures featuring the presence ( 2 a , b ) or absence ( 3 a , b ) of aurophilic intramolecular interactions were prepared by using different types of phosphole ligands (mono‐phosphole L1 or bis‐phospholes L2 , 3 ). The influence of the AuI d10 metal center(s) on the electronic, photophysical, and chiroptical properties of these unprecedented phosphole‐gold(I)‐alkynyl‐helicene complexes was examined. Experimental and theoretical results highlight the importance of ligand‐to‐ligand‐type charge transfers and the strong effect of the presence or absence of AuI–AuI interactions in 2 a , b . 相似文献
82.
Dolorès Edmont Yvon Buisson Philippe Treillard Christophe Plisson Jacques Chenault 《合成通讯》2013,43(2):217-225
A high yielding N-amination of quinolones at low temperature via the use of O-mesitylenesulfonylhydroxylamine is reported. 相似文献
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Laura Pop Pierrik Lassalas László Csaba Bencze Monica Ioana Toşa Botond Nagy Florin Dan Irimie Christophe Hoarau 《Tetrahedron: Asymmetry》2012,23(6-7):474-481
Stereoselective preparative enzymatic acylation and hydrolysis/methanolysis of various C-substituted rac-thiazol-2-yl-methanols were achieved for the preparation of enantiopure or enantiomerically enriched, naturally occurring 2-hydroxymethylthiazoles. The absolute configurations of the resulting secondary alcohols were determined by a detailed 1H NMR study of Mosher’s derivatives. 相似文献
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Multiaxial mechanical behavior of aramid fibers and identification of skin/core structure from single fiber transverse compression testing
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Judith Wollbrett‐Blitz Sébastien Joannès Rémi Bruant Christophe Le Clerc Marc Romero De La Osa Anthony Bunsell Alba Marcellan 《Journal of Polymer Science.Polymer Physics》2016,54(3):374-384
The transverse and longitudinal mechanical properties of aramid fibers like Kevlar? 29 (K29) fibers are strongly linked to their highly oriented structure. Mechanical characterization at the single fiber scale is challenging especially when the diameter is as small as 15 µm. Longitudinal tensile tests on single K29 fibers and single fiber transverse compression test (SFTCT) have been developed. Our approach consists of coupling morphological observations and mechanical experiments with SFTCT analysis by comparing analytical solutions and finite element modeling. New insights on the analysis of the transverse direction response are highlighted. Systematic loading/unloading compression tests enable to experimentally determine a transverse elastic limit. Taking account of the strong anisotropy of the fiber, the transverse mechanical response sheds light on a skin/core architecture. More importantly, results suggest that the skin of the fiber, typically representing a shell of one micrometer in thickness, has a transverse apparent modulus of 0.2 GPa. That is around more than fifteen times lower than the transverse modulus of 3.0 GPa in the core. By comparison, the measured longitudinal modulus is about 84 GPa. The stress distribution in the fiber is explored and the critical areas for damage initiation are discussed. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 374–384 相似文献
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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
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Thomas Courant Valrie Gaëlle Roullin Cyril Cadiou Maït Callewaert Marie Christine Andry Christophe Portefaix Christine Hoeffel Marie Christine deGoltstein Marc Port Sophie Laurent Luce Vander Elst Robert Muller Michaël Molinari Franoise Chuburu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2012,124(36):9253-9256
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