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41.
Arnaud Liefooghe Jérémie Humeau Salma Mesmoudi Laetitia Jourdan El-Ghazali Talbi 《Journal of Heuristics》2012,18(2):317-352
This paper discusses simple local search approaches for approximating the efficient set of multiobjective combinatorial optimization
problems. We focus on algorithms defined by a neighborhood structure and a dominance relation that iteratively improve an
archive of nondominated solutions. Such methods are referred to as dominance-based multiobjective local search. We first provide
a concise overview of existing algorithms, and we propose a model trying to unify them through a fine-grained decomposition.
The main problem-independent search components of dominance relation, solution selection, neighborhood exploration and archiving
are largely discussed. Then, a number of state-of-the-art and original strategies are experimented on solving a permutation
flowshop scheduling problem and a traveling salesman problem, both on a two- and a three-objective formulation. Experimental
results and a statistical comparison are reported in the paper, and some directions for future research are highlighted. 相似文献
42.
Dilyana Paneva Laetitia Mespouille Nevena Manolova Philippe Degée Iliya Rashkov Philippe Dubois 《Macromolecular rapid communications》2006,27(17):1489-1494
Summary: Well‐defined poly[(ethylene oxide)‐block‐(sodium 2‐acrylamido‐2‐methyl‐1‐propane sulfonate)] diblock copolymers [P(EOm‐b‐AMPSn)], have been obtained by water‐based ATRP using α‐methoxy‐ω‐(2‐methylbromoisobutyrate) poly(ethylene oxide)s (MeO‐P[EO]m‐BriB with m ranging from 12 to 113) and CuBr · 2Bpy (Bpy for 2,2′‐bipyridyl) as macroinitiator and catalytic complex, respectively. Compared to direct polymerization in water, it has been demonstrated that the water/methanol (3:1, v/v) mixture is better suited for predicting the final number‐average molar mass from the initial monomer‐to‐macroinitiator molar ratio and achieving a quite narrow polydispersity, even at high monomer conversion ( ≈ 1.4 at 80% conversion). The effect of temperature, solvent mixture composition and addition of NaCl salt on the polymerization rate and extent of control over the copolymer molecular parameters have been highlighted as well.
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Stacy Deshaies Christine le Guernev Lucas Suc Laetitia Mouls Franois Garcia Cdric Saucier 《Molecules (Basel, Switzerland)》2021,26(20)
(+)-Catechin—laccase oxidation dimeric standards were hemi-synthesized using laccase from Trametes versicolor in a water-ethanol solution at pH 3.6. Eight fractions corresponding to eight potential oxidation dimeric products were detected. The fractions profiles were compared with profiles obtained with two other oxidoreductases: polyphenoloxidase extracted from grapes and laccase from Botrytis cinerea. The profiles were very similar, although some minor differences suggested possible dissimilarities in the reactivity of these enzymes. Five fractions were then isolated and analyzed by 1D and 2D NMR spectroscopy. The addition of traces of cadmium nitrate in the samples solubilized in acetone-d6 led to fully resolved NMR signals of phenolic protons, allowing the unambiguous structural determination of six reaction products, one of the fractions containing two enantiomers. These products can further be used as oxidation markers to investigate their presence and evolution in wine during winemaking and wine ageing. 相似文献
46.
Molecularly Imprinted Polymers: Compromise between Flexibility and Rigidity for Improving Capture of Template Analogues 下载免费PDF全文
Antonelle Pardo Dr. Laetitia Mespouille Prof. Dr. Philippe Dubois Prof. Dr. Bertrand Blankert Prof. Dr. Pierre Duez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(12):3500-3509
New synthetic strategies for molecularly imprinted polymers (MIPs) were developed to mimic the flexibility and mobility exhibited by receptor/enzyme binding pockets. The MIPs were prepared by bulk polymerization with quercetin as template molecule, acrylamide as functional monomer, ethylene glycol dimethacrylate as cross‐linker, and THF as porogen. The innovative grafting of specific oligoethylene glycol units onto the imprinted cavities allowed MIPs to be obtained that exhibit extended selectivity towards template analogues. This synthetic strategy gives promising perspectives for the design of molecular recognition of molecules based on a congruent pharmacophore, which should be of interest for drug development. 相似文献
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Hexane was reacted in mixtures with excess hydrogen on 5% Rh on different supports: Al2O3 and SiO2, the latter catalyst in two states: after reduction at 603 K (LT) and after a prereduction at 1253 K (HT). The main reaction was hydrogenolysis. The catalysts were characterized with the fragment composition at different temperatures and hydrogen pressures. Two surface states could be distinguished: one with more hydrogen favored single rupture, the other with less hydrogen preferred multiple fragmentation. The transition between these states could be rather abrupt, as the surface hydrogen availability changed. The tendency to produce multiple fragments increased in the order Rh/Al2O3< Rh/SiO2-LT < Rh/SiO2-HT. 相似文献
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