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991.
Mathieu Francoeur M. Pinar Mengü Rodolphe Vaillon 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(18):2002-2018
A general algorithm is introduced for the analysis of near-field radiative heat transfer in one-dimensional multi-layered structures. The method is based on the solution of dyadic Green's functions, where the amplitude of the fields in each layer is calculated via a scattering matrix approach. Several tests are presented where cubic boron nitride is used in the simulations. It is shown that a film emitter thicker than 1 μm provides the same spectral distribution of near-field radiative flux as obtained from a bulk emitter. Further simulations have pointed out that the presence of a body in close proximity to an emitter can alter the near-field spectrum emitted. This algorithm can be employed to study thermal one-dimensional layered media and photonic crystals in the near-field in order to design radiators optimizing the performances of nanoscale-gap thermophotovoltaic power generators. 相似文献
992.
Mathieu Lions Samuel Saada Jean‐Paul Mazellier Franois Andrieu Olivier Faynot Philippe Bergonzo 《固体物理学:研究快报》2009,3(6):205-207
Thick diamond films are known to exhibit remarkably high electrical resistivity and thermal conductivity. However, on thin films, difficulties are often observed to achieve such performances. In this study, the synthesis of ultra‐thin diamond films was optimized towards the possibility to maintain high dielectric performances on layers compatible with today requirements for Silicon‐On‐Diamond technology, and namely aiming at films with thicknesses equal or below 150 nm. The nucleation of diamond nanocrystals is crucial to obtain films with thickness lower than 100 nm. A Bias Enhanced Nucleation step (BEN) was improved to achieve nucleation densities above 1011 cm–2 although the process was also tuned to limit the size of the nanocrystals during this step. The control of the carbonization of the silicon substrate is also essential to reach such a density with a high reproducibility. The BEN is followed by a growth step with optimized conditions. The films were characterized by SEM and Spectroscopic Ellipsometry. Electrical conductivity measurements were conducted on thin diamond films and values obtained on layers below 100 nm were as high as 5 × 1013 Ω cm; a value significantly higher than the state of the art for such thin films. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Cédric Caudan Ahlem Filali Dominique Lefebvre Mathieu Spérandio Elisabeth Girbal-Neuhauser 《Applied biochemistry and biotechnology》2012,166(7):1685-1702
A multi-method protocol previously proposed for the extraction of extracellular polymeric substances (EPS) from flocculated
sludges was investigated on dense aerobic granules. The protocol combines mechanical disruption by sonication and chemical
extraction using the Tween detergent and the cation chelator, EDTA. Polysaccharides were mainly recovered during the first
sonication step while proteins were recovered all along the extractive procedure with a high prevalence in the EDTA step.
These data confirmed the interest of the multi-method protocol for harvesting a diversified pool of EPS from dense granules
and for fractionation of the polymers according to their physicochemical properties. In addition, the high extractability
of proteins with EDTA confers a specific behavior of the aerobic granules towards the multi-method extraction protocol, supporting
the idea that proteins are associated in the granule matrix through ionic interactions involving divalent cations. Analysis
of the extracted EPS by anionic exchange chromatography confirmed the presence of highly anionic proteins that were specifically
detected in the extracts obtained from granules. One important question is now to investigate whether these highly anionic
proteins are involved in the aggregation and densification process and if their presence is related to the cohesive properties
of these particles. 相似文献
998.
Iminosugar‐Cyclopeptoid Conjugates Raise Multivalent Effect in Glycosidase Inhibition at Unprecedented High Levels
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Dr. Mathieu L. Lepage Jérémy P. Schneider Dr. Anne Bodlenner Alessandra Meli Prof. Francesco De Riccardis Dr. Marjorie Schmitt Prof. Céline Tarnus Dr. Nha‐Thi Nguyen‐Huynh Dr. Yannis‐Nicolas Francois Dr. Emmanuelle Leize‐Wagner Dr. Catherine Birck Alexandra Cousido‐Siah Dr. Alberto Podjarny Prof. Irene Izzo Prof. Philippe Compain 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(15):5151-5155
A series of cyclopeptoid‐based iminosugar clusters has been evaluated to finely probe the ligand content‐dependent increase in α‐mannosidase inhibition. This study led to the largest binding enhancement ever reported for an enzyme inhibitor (up to 4700‐fold on a valency‐corrected basis), which represents a substantial advance over the multivalent glycosidase inhibitors previously reported. Electron microscopy imaging and analytical data support, for the best multivalent effects, the formation of a strong chelate complex in which two mannosidase molecules are cross‐linked by one inhibitor. 相似文献
999.
Cover Picture: An Experimental and Theoretical Investigation on Pentacoordinated Cobalt(III) Complexes with an Intermediate S=1 Spin State: How Halide Ligands Affect their Magnetic Anisotropy (Chem. Eur. J. 3/2016)
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1000.
Multicomponent Synthesis of Chiral Bidentate Unsymmetrical Unsaturated N‐Heterocyclic Carbenes: Copper‐Catalyzed Asymmetric CC Bond Formation
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Dr. Claire Jahier‐Diallo Dr. Marie S. T. Morin Dr. Pierre Queval Dr. Mathieu Rouen Isabelle Artur Pierre Querard Dr. Loic Toupet Dr. Christophe Crévisy Dr. Olivier Baslé Dr. Marc Mauduit 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):993-997
A multicomponent strategy was applied to the synthesis of chiral bidentate unsaturated hydroxyalkyl‐ and carboxyalkyl‐N‐heterocyclic carbene (NHC) precursors. The newly developed low‐cost chiral ligands derived from amino alcohols and amino acids were evaluated in copper‐catalyzed asymmetric conjugated addition and asymmetric allylic alkylation, which afforded the desired tertiary and quaternary carbon stereocenters with excellent regio‐ and enantioselectivities (up to 99:1 e.r.). 相似文献