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71.
The N-tosylcarboxamide group offers the possibility of directing the Pd-catalyzed C-H arylation of arenes providing a new entry to biarylcarboxamides. Moreover, its ability to react according to different reaction conditions including intramolecular reactions makes it a pivotal directing group for a divergent synthesis of biaryl-based compounds. 相似文献
72.
Davila J Chassepot A Longo J Boulmedais F Reisch A Frisch B Meyer F Voegel JC Mésini PJ Senger B Metz-Boutigue MH Hemmerlé J Lavalle P Schaaf P Jierry L 《Journal of the American Chemical Society》2012,134(1):83-86
Cell adhesion processes take place through mechanotransduction mechanisms where stretching of proteins results in biological responses. In this work, we present the first cyto-mechanoresponsive surface that mimics such behavior by becoming cell-adhesive through exhibition of arginine-glycine-aspartic acid (RGD) adhesion peptides under stretching. This mechanoresponsive surface is based on polyelectrolyte multilayer films built on a silicone sheet and where RGD-grafted polyelectrolytes are embedded under antifouling phosphorylcholine-grafted polyelectrolytes. The stretching of this film induces an increase in fibroblast cell viability and adhesion. 相似文献
73.
Dr. Teresa Hungría Covadonga Correas Dr. Florent Houdellier Dr. Octavio Peña Dr. Eladio Vila Prof. Dr. Alicia Castro 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(29):9075-9082
In the last ten years, the study and the search for new multiferroic materials have been a major challenge due to their potential applications in electronic technology. In this way, bismuth‐containing perovskites (BiMO3), and particularly those in which the metal M position is occupied by a magnetically active cation, have been extensively investigated as possible multiferroic materials. From the point of view of synthesis, only a few of the possible bismuth‐containing perovskites can be prepared by conventional methods but at high pressures. Herein, the preparation of one of these potential multiferroic systems, the solid solution xBiMnO3‐(1?x)PbTiO3 by mechanosynthesis is reported. Note that this synthetic method allows the oxides with high x values, and more particularly the BiMnO3 phase, to be obtained as nanocrystalline phases, in a single step and at room temperature without the application of external pressure. These results confirm that, in the case of Bi perovskites, mechanosynthesis is a good alternative to high‐pressure synthesis. These materials have been studied from the point of view of their structural characteristics by precession electron diffraction and magnetic property measurements. 相似文献
74.
Yannick Crémillieux Florent Goutailler Bruno Montcel Dominique Grand Gérard Vermeulen Pierre-Etienne Wolf 《Applied magnetic resonance》2012,43(1-2):167-180
The volume of polarized sample and the delay required between successive polarizations of samples represent serious constraints for dynamic nuclear polarization (DNP) applications. With these limitations in mind, a DNP polarizer, based on a super-wide bore (150-mm diameter) vertical magnet operating at 3.35?T, was designed. The working diameter for loading/unloading samples is equal to 46?mm and the microwave cavity can accommodate up to three samples. The cryostat can be cooled to 4.2?K in typically 2?h and filled with liquid helium in 1?h. Once filled with liquid helium, the cryostat hold time is on the order of 4?h and a minimum temperature of 1.19?K can be reached. In situ polarization levels at low temperature were measured between 5 and 10?% in single and multiple samples of 13C-labeled urea and glycine. 相似文献
75.
B. Sitamtze Youmbi Serge Zékeng Samuel Domngang Florent Calvayrac Alain Bulou 《Ionics》2012,18(4):371-377
To date, the fastest lithium ion-conducting solid electrolytes known are the perovskite-type ABO3 oxide, with A = Li, La and B = Ti, lithium lanthanum titanate (LLTO)
Li3x La( 2 \mathord