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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   
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Journal of Thermal Analysis and Calorimetry - The method of evaluating the magnetocaloric effect (MCE) and heat capacity of various magnetic samples from calorimetric experiments are presented....  相似文献   
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For the first time, chloroform and 2-butanol were used as solvent systems for the preparation of ZrO2–PANI and CeO2–PANI composites. Solubility of the synthesized composites was studied in chloroform, N-methyl-2-pyrrolidinone (NMP), and in mixture of toluene?+?2-propanol (2:1). XRD and cyclic voltammetry data showed that the ZrO2–PANI and CeO2–PANI composites possess both crystalline and amorphous domains indicating some sort of conductivity. TGA results showed that ZrO2–PANI composite have a better thermal stability than pure PANI; however, CeO2–PANI composite has lower thermal stability than pure PANI. The conjugated unsaturated structure of PANI is responsible for the enhanced photocatalytic properties of ZrO2–PANI and CeO2–PANI. Photocatalytic results showed that, at photolysis time of 60 min, rhodamine B (RhB) dye was degraded up to 34 and 35% by ZrO2–PANI and CeO2–PANI, respectively. The degradation products of RhB were quantified by LC–MS and GC–MS, and accordingly, a detailed pathway was proposed.  相似文献   
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Journal of Solid State Electrochemistry - Scientists are increasingly interested in improving electroactive technologies for supercapacitor applications, since energy storage devices have improved...  相似文献   
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Journal of Solid State Electrochemistry - In this work, a polymer composite based on poly 4-aminothiophenol (p-ATP) is prepared via a facile electrochemical route and is used as an appropriate...  相似文献   
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The Claisen-Schmidt condensation of 1-(triphenylmethyl)-2-imidazolecarboxaldehyde with acetophenones yielded 1-aryl-3-[1-(triphenylmethyl)-2-imidazolyl]propen-1-ones 7 . Selective catalytic hydrogenation over platinum of 7 furnished 1-aryl-3-(2-imidazolyl)-1-propanones 8 . An alternate synthesis of 8 started with sodium borohydride reduction of 7 to give allylic alcohols, 1-aryl-3-[1-(triphenylmethyl)-2-imidazolyl]-2-propen-1-ols 10 , which were rearranged by hot aqueous sodium to 8 . Acid hydrolysis of 8 provided the title compounds and triphenylmethanol.  相似文献   
40.
Lithiation of 1-(dimethylsulfamoyl)imidazole by n-butyllithium, followed by substitution with dimethylformamide provided 1-(dimethylsulfamoyl)-2-imidazolecarboxaldehyde in 19% yield. When 1-(dimethylsulfamoyl)-2-(tert-butyldimethylsilyl)imidazole was lithiated by sec-butyllithium, followed by methyl formate, there was obtained 1-(dimethylsulfamoyl)-2-(tert-butyldimethylsilyl)-5-imidazolecarbox-aldehyde (57%). Removal of the silyl group by acetic acid yielded 1-(dimethylsulfamoyl)-5-imidazolecarbxaldehyde ( 11 , 96%) as a gum. Isomerization of 11 took place slowly at room temperature (10 days), or faster in tetrahydrofuran solution containing triethylamine (2 hours) to form crystalline 1-(dimethylsul-famoyl)-4-imidazolecarboxaldehyde (12) in 68% yield. Proton and carbon-13 nmr spectra were analyzed to determine the structure of the isomers. However, only X-ray crystallography established the structure of 1-(dimethylsulfamoyl)-4-imidazolecarboxaldehyde, unequivocally. A mechanism for the isomerization of 11 to 12 is proposed.  相似文献   
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