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571.
Oana?StanEmail author Renaud?Sirdey Jacques?Carlier Dritan?Nace 《4OR: A Quarterly Journal of Operations Research》2015,13(3):309-334
In this paper, we study the problem of joint placement and routing, both in the deterministic and stochastic cases, arising in the field of compilation of dataflow applications for manycore architectures. A GRASP algorithm is first proposed for solving the deterministic version and extended afterwards to treat the chance-constrained program with uncertainty affecting the weights of a dataflow process network. Extensive computational results, on representative synthetic benchmark and real data, illustrate the practical relevance of the approach, as well as the robustness of the obtained stochastic solutions. 相似文献
572.
Mathilde LachiaSébastien Iriart Myriam BaalouchAlain De Mesmaeker Renaud Beaudegnies 《Tetrahedron letters》2011,52(25):3219-3222
We report here the use of the readily accessible ethyl-2-(2-chloroethyl)acrylate as a new very versatile α-cyclopropylester cation synthon, which reacts efficiently and selectively with carbon-, nitrogen-, sulfur- or phosphorus-centered nucleophiles through Michael addition followed by intramolecular capture of the incipient ester enolate to afford funtionalized cyclopropane esters in high yields. 相似文献
573.
S. S. Vaisakh Mehrad Hassanzadeh Renaud Metz S. Ramakrishnan Delphine Chappelle J. D. Sudha S. Ananthakumar 《先进技术聚合物》2014,25(2):240-248
Nano/micro ceramic‐filled epoxy composite materials have been processed with various percentage additions of SiO2, Al2O3 ceramic fillers as reinforcements selected from the nano and micro origin sources. Different types of filler combinations, viz. only nano, only micro, nano/micro, and micro/micro particles, were designed to investigate their influence on the thermal expansion, thermal conductivity, and dielectric properties of epoxy polymers. Thermal expansion studies were conducted using thermomechanical analysis that revealed a two‐step expansion pattern consecutively before and after vitreous transition temperatures. The presence of micro fillers have shown vitreous transition temperature in the range 70–80°C compared with that of nano structured composites in which the same was observed as ~90°C. Similarly, the bulk thermal conductivity is found to increase with increasing percentage of micron‐size Al2O3. It was established that the addition of micro fillers lead to epoxy composite materials that exhibited lower thermal expansion and higher thermal conductivity compared with nano fillers. Moreover, nano fillers have a significantly decisive role in having low bulk dielectric permittivity. In this study, epoxy composites with a thermal expansion coefficient of 2.5 × 10?5/K, thermal conductivity of 1.18 W/m · K and dielectric permittivity in the range 4–5 at 1 kHz have been obtained. The study confirms that although the micro fillers seem to exhibit good thermal conductivity and low expansion coefficient, the nano‐size ceramic fillers are candidate as cofillers for low dielectric permittivity. However, a suitable proportion of nano/micro‐mixed fillers is necessary for achieving epoxy composites with promising thermal conductivity, controlled coefficient of thermal expansion and dielectric permittivity. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
574.
Combining deflective dielectrophoretic barriers with controlled pressure driven liquid flows in microfluidic devices allows accurate handling of particles such as biological cells in suspensions. Working towards cell-based lab-on-a-chip applications, a platform permitting rapid testing of devices having different dielectrophoretic and fluidic subunits was developed. The performance of such a system is shown in the cases of (A) flooding a small number of immobilised cells with a dye and (B) transient buffer swapping of a large number of cells in flow. The transition times for moving cells from one reagent to the other are below 0.5 s in the case of flow-through cell dipping. 相似文献
575.
Dmitry Aldakov Claudia Querner Yann Kervella Bruno Jousselme Renaud Demadrille Emanuela Rossitto Peter Reiss Adam Pron 《Mikrochimica acta》2008,160(3):335-344
The preparation of new molecular hybrids consisting of CdSe semiconductor nanocrystals, surface-functionalized with conductive
and electrochemically active oligothiophene ligands, is described. Specially synthesized aniline-terminated oligoalkylthiophenes
containing one, two, or four thiophene units were used for the grafting on CdSe nanocrystals, previously surface-functionalized
with 4-formyldithiobenzoate. The electrochemical activity of both the inorganic and the organic parts of the hybrid was investigated
by cyclic voltammetry. The oxidative doping of the organic part of the hybrid is irreversible, contrary to the case of the
“free” non-grafted ligand which shows reversible doping. Furthermore, the electrochemical doping of the surface ligands, occurring
at lower potentials than the oxidation of the nanocrystals, perturbs the latter process via charging of the ligands followed by slow relaxation processes.
The first two authors contributed equally to this work
Correspondence: Peter Reiss, Adam Pron, DSM/DRFMC/SPrAM (UMR 5819 CEA-CNRS-Université Joseph Fourier 1)/LEMOH CEA Grenoble,
17 rue des Martyrs, F-38054 Grenoble Cedex 9, France 相似文献
576.
Vermoortele F Maes M Moghadam PZ Lennox MJ Ragon F Boulhout M Biswas S Laurier KG Beurroies I Denoyel R Roeffaers M Stock N Düren T Serre C De Vos DE 《Journal of the American Chemical Society》2011,133(46):18526-18529
Para-disubstituted alkylaromatics such as p-xylene are preferentially adsorbed from an isomer mixture on three isostructural metal-organic frameworks: MIL-125(Ti) ([Ti(8)O(8)(OH)(4)(BDC)(6)]), MIL-125(Ti)-NH(2) ([Ti(8)O(8)(OH)(4)(BDC-NH(2))(6)]), and CAU-1(Al)-NH(2) ([Al(8)(OH)(4)(OCH(3))(8)(BDC-NH(2))(6)]) (BDC = 1,4-benzenedicarboxylate). Their unique structure contains octahedral cages, which can separate molecules on the basis of differences in packing and interaction with the pore walls, as well as smaller tetrahedral cages, which are capable of separating molecules by molecular sieving. These experimental data are in line with predictions by molecular simulations. Additional adsorption and microcalorimetric experiments provide insight in the complementary role of the two cage types in providing the para selectivity. 相似文献
577.
Abstract Herein, we introduce one of the first examples of asymmetric organocatalyzed synthesis of 1,2-dihydropyridines, affording enantioselective access to and partially solving regioselectivity challenges in the synthesis of dihydropyridines. We demonstrate that through modification of organocatalysts both 1,2- and 1,4-dihydropyridines (1,2- and 1,4-DHPs) can be obtained with high regioselectivity (ratio of 1,2-DHP/1,4-DHP from 95/5 to 0/100) and enantioselectivity (33% ee for 1,2-DHPs and up to 98% ee for 1,4-DHPs) in good yields (up to 87%). 相似文献
578.
Bouziane A Hélou M Carboni B Carreaux F Demerseman B Bruneau C Renaud JL 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(18):5630-5637
Secondary allylic alcohols were synthesized from linear allylic halides or carbonates using a catalytic amount of a ruthenium complex in the presence of boronic acid. The effects of solvent, base, ruthenium precursor, and boronic acid were fully explored, and the scope of the reaction was extended to various substrates. We also describe a preliminary investigation towards an enantioselective process. 相似文献
579.
Mbaye MD Renaud JL Demerseman B Bruneau C 《Chemical communications (Cambridge, England)》2004,(16):1870-1871
Regio- and enantioselective substitution of cinnamyl chloride by phenols has been achieved with up to 82% enantiomeric excess, using a ruthenium catalyst prepared from [Cp*(CH(3)CN)(3)Ru][PF(6)] and a chiral bisoxazoline ligand. 相似文献
580.
Fatemeh Sadat Majedi Mohammad Mahdi Hasani‐Sadrabadi Erfan Dashtimoghadam Amir Hossein Haghighi Arnaud Bertsch Homayoun Moaddel Philippe Renaud 《固体物理学:研究快报》2012,6(7):318-320
Interaction between negatively charged Nafion® and a positively charged polybenzimidazole‐decorated carbon nanotube leads to the formation of an ionic complex with high charge density for proton conduction, which can lead to an improvement in transport properties. Here we investigate the high‐temperature and low‐humidity proton conductivity of this nanocomposite membrane as a potential membrane for fuel cell applications.