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81.
M. Bardoux A. Bousseksou G. Tessier S. Bouchoule D. Fournier A. Salhi Y. Rouillard F. Genty 《Optics and Lasers in Engineering》2009,47(3-4):473-476
Thermal characterization of semiconductor lasers is an important issue for optoelectronics. This paper presents our thermoreflectance measurements on two different types of laser diodes: classical ridge laser diodes and vertical cavity surface emitting lasers (VCSELs). We first studied the external temperature increase in ridge diodes in order to determine inhomogeneity. Then, we tried to determine the inner temperature of the VCSELs. 相似文献
82.
Let T be a bounded operator and let \(k \ge 2\) be an integer. We study in this paper the following question: T is a partial isometry implies that \(T^k\) is a partial isometry and conversely. 相似文献
83.
In this paper we investigate the existence of integrable solutions of a nonlinear integral equation of Hammerstein type on an unbounded interval. Our analysis relies on a Krasnosel’skii type fixed point theorem and uses the technique of measure of weak noncompactness. 相似文献
84.
F. Amrani A. Haboucha M. Salhi H. Leblond A. Komarov F. Sanchez 《Applied physics. B, Lasers and optics》2010,99(1-2):107-114
We investigate experimentally ordered and disordered pattern formation of solitons in a double-clad fiber laser. We point out an analogy between the different states of matter and the states of a set of dissipative solitons. In particular, we have identified a gas, a supersonic gas flow, a liquid, a polycrystal and a crystal of solitons. The different states are obtained only by adjustment of the intracavity phase plates. 相似文献
85.
Removal of bromide and iodide anions from drinking water by silver-activated carbon aerogels 总被引:1,自引:0,他引:1
Sánchez-Polo M Rivera-Utrilla J Salhi E von Gunten U 《Journal of colloid and interface science》2006,300(1):437-441
The aim of this study is to analyze the use of Ag-doped activated carbon aerogels for bromide and iodide removal from drinking water and to study how the activation of Ag-doped aerogels affects their behavior. It has been observed that the carbonization treatment and activation process of Ag-doped aerogels increased the surface area value ( [Formula: see text] ), whereas the volume of meso-(V(2)) and macropores (V(3)) decreased slightly. Chemical characterization of the materials revealed that carbonization and especially activation process considerably increased the surface basicity of the sample. Original sample (A) presented acidic surface properties (pH(PZC)=4.5) with 21% surface oxygen, whereas the sample that underwent activation showed mainly basic surface chemical properties (pH(PZC)=9.5) with only 6% of surface oxygen. Carbonization and especially, activation process considerable increased the adsorption capacity of bromide and iodide ions. This would mainly be produced by (i) an increase in the microporosity of the sample, which increases Ag-adsorption sites available to halide anions, and (ii) a rise of the basicity of the sample, which produces an increase in attractive electrostatic interactions between the aerogel surface, positively charged at the working pH (pH(solution)相似文献
86.
87.
Jan Stanek Loren B. Andreas Kristaps Jaudzems Diane Cala Daniela Lalli Andrea Bertarello Tobias Schubeis Inara Akopjana Svetlana Kotelovica Kaspars Tars Andrea Pica Serena Leone Delia Picone Zhi‐Qiang Xu Nicholas E. Dixon Denis Martinez Mlanie Berbon Nadia El Mammeri Abdelmajid Noubhani Sven Saupe Birgit Habenstein Antoine Loquet Guido Pintacuda 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(50):15730-15735
88.
Enhancements to two exact algorithms from the literature to solve the vertex P-center problem are proposed. In the first approach modifications of some steps are introduced to reduce the number of ILP iterations needed to find the optimal solution. In the second approach a simple enhancement which uses tighter initial lower and upper bounds, and a more appropriate binary search method are proposed to reduce the number of subproblems to be solved. These ideas are tested on two well known sets of problems from the literature (i.e., OR-Lib and TSP-Lib problems) with encouraging results.Mathematics Subject Classifications (2000) 90B10, 90B80, 90C09, 90C47. 相似文献
89.
A series of performance improving heuristics are developed and embedded into the procedure of Lagrangean heuristics. The principles and ideas of these heuristics are used to build a general framework with which a variety of large Capacitated Plant Location Problems (CPLP) are solved, including the multi-capacitated case. A significant improvement over the results discussed in the literature is recorded. The single-source multi-Capacitated Plant Location Problem, which has not been addressed in the literature, is also tackled with encouraging results. 相似文献
90.
Bouabdallah I M'Barek LA Zyad A Ramdani A Zidane I Melhaoui A 《Natural product research》2007,21(4):298-302
The evaluation of the in vitro cytotoxic properties of two pyrazole compounds: 1-(4-nitrophényl)-3,5-diméthylpyrazole (1) and 1,1'-di(4-nitrophényl)-5,5'-diisopropyl-3,3'-bipyrazole (2) was investigated against Hep cell line (Human laryngeal carcinoma). These two compounds showed an important cytotoxic activity on the Hep cell line, with IC(50): 8.25 microg mL(-1) for the compound 1; IC(50): 10.20 microg mL(-1) for the compound 2 while the IC(50) for adriamycine used as positive control was 3.62 microg mL(-1). 相似文献