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491.
Nechab M Besson E Campolo D Perfetti P Vanthuyne N Bloch E Denoyel R Bertrand MP 《Chemical communications (Cambridge, England)》2011,47(18):5286-5288
Mesoporous silica grafted with a tertiary amine was used as a basic nanocatalyst to promote in confined medium the enantioselective cascade rearrangement of enediynes based on the phenomenon of memory of chirality; the multi-substrates recyclable catalytic reagent could easily be recovered by simple filtration, and reused without any decrease in activity even when changing the solvent. 相似文献
492.
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
493.
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
494.
Renaud Lambiotte Vincent D. Blondel Etienne Huens Zbigniew Smoreda 《Physica A》2008,387(21):5317-5325
In this paper, we analyze statistical properties of a communication network constructed from the records of a mobile phone company. The network consists of 2.5 million customers that have placed 810 million communications (phone calls and text messages) over a period of 6 months and for whom we have geographical home localization information. It is shown that the degree distribution in this network has a power-law degree distribution k−5 and that the probability that two customers are connected by a link follows a gravity model, i.e. decreases as d−2, where d is the distance between the customers. We also consider the geographical extension of communication triangles and we show that communication triangles are not only composed of geographically adjacent nodes but that they may extend over large distances. This last property is not captured by the existing models of geographical networks and in a last section we propose a new model that reproduces the observed property. Our model, which is based on the migration and on the local adaptation of agents, is then studied analytically and the resulting predictions are confirmed by computer simulations. 相似文献
495.
496.
Dr. Rebecca El Khawaja Dr. Guillaume Rochard Dr. Eric Genty Dr. Christophe Poupin Prof. Stéphane Siffert Prof. Renaud Cousin 《欧洲无机化学杂志》2023,26(20):e202300213
A series of mixed oxides (Mn-Mg-Al) is prepared by coprecipitation via a hydrotalcite route with different manganese ratios. Structural, textural, and redox properties are studied by XRD, N2-sorption, H2-TPR, and XPS techniques. MnxMg6-xAl2-O mixed oxides (with 0≤x≤6) are tested in the total oxidation of ethanol and toluene, two probe molecules representing respectively oxygenated and aromatic VOCs. Catalysts with higher manganese contents have shown the best catalytic performance for the oxidation of both ethanol and toluene. The surface activity of the materials is mainly related to the presence of manganese species in three different oxidation states (+II, +III, and +IV) in the bulk and on the material's surface. Since high Mn-content catalysts showed similar physicochemical properties and catalytic activity, Mn4Mg2-O is selected as the optimal composition of these materials. Furthermore, its aging test is compared to that of noble metal-based commercial catalysts (Pd/γ-Al2O3). 相似文献
497.