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61.
Najahi E Sudor J Chabchoub F Nepveu F Zribi F Duval R 《Molecules (Basel, Switzerland)》2010,15(12):8841-8855
In this paper we present the room temperature synthesis of a novel serie of 1,4-disubstituted-1,2,3-triazoles 4a-l by employing the (3+2) cycloaddition reaction of pyrimidinones containing alkyne functions with different model azides in the presence of copper sulphate and sodium ascorbate. To obtain the final triazoles, we also synthesized the major precursors 6-amino-5-cyano-1,4-disubstituted-2(1H)-pyrimidinones 3a-r from ethyl 2,2-dicyanovinylcarbamate derivatives 2a-c and various primary aromatic amines containing an alkyne group. The triazoles were prepared in good to very good yields. 相似文献
62.
Cyrielle Roquelet Jean‐Sébastien Lauret Dr. Valérie Alain‐Rizzo Dr. Christophe Voisin Dr. Romain Fleurier Dr. Morgan Delarue Damien Garrot Dr. Annick Loiseau Prof. Philippe Roussignol Prof. Jacques A. Delaire Prof. Emmanuelle Deleporte Prof. 《Chemphyschem》2010,11(8):1667-1672
We report on a new, original and efficient method for π‐stacking functionalization of single‐wall carbon nanotubes. This method is applied to the synthesis of a high‐yield light‐harvesting system combining single‐wall carbon nanotubes and porphyrin molecules. We developed a micelle‐swelling technique that leads to controlled and stable complexes presenting an efficient energy transfer. We demonstrate the key role of the organic solvent in the functionalization mechanism. By swelling the micelles, the solvent helps the non‐water‐soluble porphyrins to reach the micelle core and allows a strong enhancement of the interaction between porphyrins and nanotubes. This technique opens new avenues for the functionalization of carbon nanostructures. 相似文献
63.
Thierry Benoist Bertrand Estellon Fr��d��ric Gardi Romain Megel Karim Nouioua 《4OR: A Quarterly Journal of Operations Research》2011,9(3):299-316
This paper introduces LocalSolver 1.x, a black-box local-search solver for general 0-1 programming. This software allows OR
practitioners to focus on the modeling of the problem using a simple formalism, and then to defer its actual resolution to
a solver based on efficient and reliable local-search techniques. Started in 2007, the goal of the LocalSolver project is
to offer a model-and-run approach to combinatorial optimization problems which are out of reach of existing black-box tree-search
solvers (integer or constraint programming). Having outlined the modeling formalism and the main technical features behind
LocalSolver, its effectiveness is demonstrated through an extensive computational study. The version 1.1 of LocalSolver can
be freely downloaded at and used for educational, research, or commercial purposes. 相似文献
64.
Negative electrorheological responses induced by micro-particle electrorotation in two-dimensional Couette flow geometries are analyzed by a set of continuum modeling field equations originating from anti-symmetric/couple stress theories in the finite spin viscosity small spin velocity (FSV) limit. Analytical solutions are obtained for the first time to express the spin velocity, linear velocity, and effective viscosity in terms of the electric field strength, driving shear rate, boundary condition selection parameter, and spin viscosity. Good agreement is achieved between the FSV theoretical predictions presented herein and the experimental measurements reported in recent literature for the effective viscosity for low driving shear rates. 相似文献
65.
Gerd Finke Pierre Lemaire Jean-Marie Proth Maurice Queyranne 《European Journal of Operational Research》2009,199(3):702-705
In this paper, we present a new objective function for scheduling on parallel machines: minimizing the number of machines for schedules of minimum length. We study its complexity and we prove the NP-completeness of this problem, even if there is no precedences or for unitary execution times. We propose several polynomial algorithms for various particular cases. 相似文献
66.
cis-2-Oxo-5-hydroxymethyl-1,3,2-dioxathiolane 2a can be efficiently resolved by a lipase from Pseudomonas cepacia-catalysed acylation reaction with vinylbutyrate. Compound 2a was directly prepared from glycerol in one step. This first lipase-catalysed resolution of a cyclic sulphite derivative provides a potentially useful activated chiral synthon. 相似文献
67.
Leyla Pehlivan Stéphane Laval Patrice Demonchaux Marc Lemaire 《Tetrahedron letters》2010,51(15):1939-10974
An efficient reduction of the nitro group with a catalytic amount of Fe(acac)3 and TMDS in THF at 60 °C affording the corresponding amine is described. 相似文献
68.
We establish a duality formula for the problem Minimize f(x)+g(x) for h(x)+k(x)<0 where g, k are extended-real-valued convex functions and f, h belong to the class of functions that can be written as the lower envelope of an arbitrary family of convex functions. Applications in d.c. and Lipschitzian optimization are given. 相似文献
69.
The stochastic finite element method presented in this Note consists in representing in a probabilistic form the response of a linear mechanical system whose material properties and loading are random. Each input random variable is expanded into a Hermite polynomial series in standard normal random variables. The response (e.g., the nodal displacement vector) is expanded onto the so-called polynomial chaos. The coefficients of the expansion are obtained by a Galerkin-type method in the space of probability. To cite this article: B. Sudret et al., C. R. Mecanique 332 (2004). 相似文献
70.
A simple and practical procedure for the reduction of acetals to ethers is described. It is based on the use of a 1,1,3,3-tetramethyldisiloxane (TMDS)-Pd/C system in the presence of a Brønsted acid as the co-catalyst. The reaction occurs under mild conditions and ethers are obtained in high yields. 相似文献