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991.
Pascal Miéville Puneet Ahuja Dr. Riddhiman Sarkar Dr. Sami Jannin Dr. Paul R. Vasos Dr. Sandrine Gerber‐Lemaire Dr. Mor Mishkovsky Dr. Arnaud Comment Prof. Rolf Gruetter Dr. Olivier Ouari Prof. Paul Tordo Prof. Geoffrey Bodenhausen 《Angewandte Chemie (International ed. in English)》2010,49(43):7834-7834
992.
993.
Antibacterial poly(ethylene terephthalate) surfaces obtained from thymyl methacrylate polymerization 下载免费PDF全文
Sophie Bedel Bénédicte Lepoittevin Ludovic Costa Olivier Leroy Diana Dragoe Jérôme Bruzaud Jean‐Marie Herry Morgan Guilbaud Marie‐Noëlle Bellon‐Fontaine Philippe Roger 《Journal of polymer science. Part A, Polymer chemistry》2015,53(17):1975-1985
Thymol, an antibacterial agent was used for the preparation of a methacrylic monomer. The conventional and atom transfer radical (ATRP) polymerizations of this monomer were studied using different conditions. Then, the functionalization of poly(ethylene terephthalate) (PET) films by “grafting from” ATRP using this monomer was investigated. In this aim, a three steps procedure was developed. The surfaces were first treated by NH3 plasma treatment to incorporate primary amino functions. Then, in a second step, ATRP initiator was grafted by reaction with bromoisobutyryl bromide. Surface initiated ATRP of thymyl methacrylate was performed in solution in the presence of a sacrificial initiator. The efficiency of these reactions was confirmed by X‐ray photoelectron spectroscopy. Wetting properties and surface energy were found to vary systematically depending to the type of functionalization and grafting. The poly(thymyl methacrylate)‐grafted PET surfaces exhibit resistance to bacterial adhesion toward Pseudomonas aeruginosa, Listeria monocytogenes, and Staphylococcus aureus strains. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1975–1985 相似文献
994.
Dominique Blanchard Olivier Guibé Hicham Redwane 《Annali di Matematica Pura ed Applicata》2008,187(3):405-433
We consider a class of quasi-linear diffusion problems involving a matrix A(t,x,u) which blows up for a finite value m of the unknown u. Stationary and evolution equations are studied for L
1 data. We focus on the case where the solution u can reach the value m. For such problems we introduce a notion of renormalized solutions and we prove the existence of such solutions.
相似文献
995.
Isabelle Kerzaon Yves F. Pouchus Fabrice Monteau Bruno Le Bizec Marie‐Renée Nourrisson Jean‐François Biard Olivier Grovel 《Rapid communications in mass spectrometry : RCM》2009,23(24):3928-3938
Penicillium expansum is a ubiquitous species for which there are only few reports for chemical investigation in marine environments. Among the numerous secondary metabolites produced by this species, communesins represent a new class of cytotoxic and insecticidal indole alkaloids. In this study, we investigated a marine P. expansum strain exhibiting neuroactivity on a Diptera larvae bioassay. Bio‐guided purification led to the isolation and the identification of communesin B as the main active compound by HRMS and 1H and 13C NMR. Liquid chromatography analyses with detection by electrospray ionization coupled with tandem mass spectrometry (LC/ESI‐MS/MS) and high‐resolution tandem mass spectrometry (LC/HRMS/MS) allowed the identification and characterization of four other known communesins (A, D, E and F) in the crude extract. A fragmentation model for dimethyl epoxide communesins was proposed after detailed interpretation of their MS/MS spectra. Further analyses of the extract using the modelled fragmentations led to the detection of seven new communesins found as minor compounds. Chemical structural elucidation of these new derivatives is discussed based on their fragmentation characteristics. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
996.
Lionel Moisan Eric Doris Bernard Rousseau Pierre Thury 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):o792-o794
The title compounds are indole alkaloids of the Iboga class. In both compounds, viz. catharanthinol methanol solvate, C20H24N2O·CH4O, (I), and dihydrocatharanthinol monohydrate, C20H26N2O·H2O, (II), a nitrogen‐containing seven‐membered ring is fused to the indole system and shares two sides with a tricyclic isoquinuclidine group. The main difference between (I) and (II) is the presence of a C=C bond in the isoquinuclidine ring in (I). The presence of amine and hydroxy groups in these molecules and of methanol [in (I)] or water [in (II)] solvent molecules results in intra‐ and/or intermolecular hydrogen bonding. 相似文献
997.
Well‐balanced finite difference weighted essentially non‐oscillatory schemes for the blood flow model 下载免费PDF全文
The blood flow model maintains the steady‐state solutions, in which the flux gradients are non‐zero but exactly balanced by the source term. In this paper, we design high order finite difference weighted essentially non‐oscillatory (WENO) schemes to this model with such well‐balanced property and at the same time keeping genuine high order accuracy. Rigorous theoretical analysis as well as extensive numerical results all indicate that the resulting schemes verify high order accuracy, maintain the well‐balanced property, and keep good resolution for smooth and discontinuous solutions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
998.
N-Hydroxymethylation of lactams was achieved using paraformaldehyde in acetone in the presence of K2CO3 and water under sonication conditions. 相似文献
999.
1000.
A wave-front sensor is described that uses a programmable moving aperture to scan an incoming wave front. The position of the diffraction spot is recorded behind an objective lens with a two-dimensional sensor and gives an estimate of the local slope at the aperture position. Then the wave front is reconstructed by processing of the slope data. The device is basically a programmable Hartmann wave-front sensor. Compared with a microlens Shack-Hartmann wave-front sensor, its much longer focal length provides higher resolution, although real-time operation is lost. A practical implementation of the new scanner with a liquid-crystal television as the programmable aperture is presented. 相似文献