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Bridged 3,3″′-didodecylquaterthiophene-based dimers: design,synthesis, and optoelectronic properties
Claude Niebel Maud Jenart Christelle Gautier Yves Henri Geerts 《Tetrahedron》2012,68(27-28):5599-5605
Five functionalized quaterthiophene dimers including a non-conjugated bridge have been designed and efficiently synthesized. The synthetic pathways explored toward these dimers revealed unexpected features, such as the direct formation of secondary and tertiary quaterthiophene amines through a procedure initially developed for the preparation of primary amine exclusively. All these dimers possess a promising potential for the elaboration of semiconducting materials with a charge transport of higher dimensionality compared to quaterthiophene. 相似文献
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Christelle Mouveaux Roger de Jaeger Joëlle Levalois-Grützmacher 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1541-1544
Tris(benzocrown ether)s 2a , b X = P(NMeN=CH-B15C5) 3 (X=O, S) and tri[bis(benzocrown ether)] [N=P(NMeN=CH-B15C5) 2 ] 3 3 strongly chelate with alkali metal salts and their efficiency and selectivity in binding these salts are compared with those of the monomeric crown 1 . Data obtained from salt distribution equilibrium in water-chloroform show these ligands to be excellent extracting agents, especially for K + and Rb + . Furthermore, compound 3 is able to transport K + selectively. 相似文献
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Christelle Perreur Jean‐Pierre Habas Jean Peyrelasse Alain Lapp Jeanne Francois 《Macromolecular Symposia》2001,166(1):127-138
The physico‐chemical properties of Tetronic® 908 in aqueous solution have been explored on a wide range of temperature and concentration. This system presents interesting rheological properties depending on the polymer concentration in solution, and temperature. For weight percentage p comprised between 5% and 20%, the viscosity of the solution passes through a maximum. Small angle neutron scattering experiments show that the increase in the viscosity is due to the progressive aggregation of the chains. For higher weight percentages, the viscosity of the system diverges and the mixture becomes “gel‐like”. SANS studies of the same solution indicate that the micelles are organized in a cubic structure. We have developed a model which suitably describes the SANS curves of the system in the region where micelles are formed. It allows the calculation of several parameters (volume fraction of the micelles, size, composition). The evolution of these parameters with temperature and polymer concentration is detailed. Comparisons with models of literature are discussed. 相似文献
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Stéphane Mabic Christelle Franot 《Journal of the American Society for Mass Spectrometry》1997,8(12):1255-1256
The electron-induced mass spectrometry of 1-substituted-4-phenyl-1,2-dihydropyridines is characterized by a [M-1] peak that accounts for the base peak, and a fragment corresponding to the loss of the N-substituent in every example examined. 相似文献
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Marine Cotte Victor Gonzalez Frederik Vanmeert Letizia Monico Catherine Dejoie Manfred Burghammer Loïc Huder Wout de Nolf Stuart Fisher Ida Fazlic Christelle Chauffeton Gilles Wallez Núria Jimnez Francesc Albert-Tortosa Nati Salvad Elena Possenti Chiara Colombo Marta Ghirardello Daniela Comelli Ermanno Avranovich Clerici Riccardo Vivani Aldo Romani Claudio Costantino Koen Janssens Yoko Taniguchi Joanne McCarthy Harald Reichert Jean Susini 《Molecules (Basel, Switzerland)》2022,27(6)
The European Synchrotron Radiation Facility (ESRF) has recently commissioned the new Extremely Brilliant Source (EBS). The gain in brightness as well as the continuous development of beamline instruments boosts the beamline performances, in particular in terms of accelerated data acquisition. This has motivated the development of new access modes as an alternative to standard proposals for access to beamtime, in particular via the “block allocation group” (BAG) mode. Here, we present the recently implemented “historical materials BAG”: a community proposal giving to 10 European institutes the opportunity for guaranteed beamtime at two X-ray powder diffraction (XRPD) beamlines—ID13, for 2D high lateral resolution XRPD mapping, and ID22 for high angular resolution XRPD bulk analyses—with a particular focus on applications to cultural heritage. The capabilities offered by these instruments, the specific hardware and software developments to facilitate and speed-up data acquisition and data processing are detailed, and the first results from this new access are illustrated with recent applications to pigments, paintings, ceramics and wood. 相似文献