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61.
In this paper we prove the existence of integrable solutions for a generalized mixed type operator equation, which contains many key integral and functional equations appearing frequently in Mathematical literature. Our main tool is a Krasnosel’skii type fixed point theorem recently proved by Latrach and Taoudi, the first author. An existence theory for a class of nonlinear transport equations is also developed.  相似文献   
62.
We have designed and performed an experiment that permitted direct observation of Brillouin backscattering in an Yb-doped double-clad fiber laser. Fifteen Brillouin-shifted frequencies were observed for the first time to our knowledge. We clearly demonstrate that stimulated Brillouin scattering is directly responsible for both fast transient dynamics of the laser and reduction of the laser's pulse width.  相似文献   
63.
An improved genetic algorithm (GA) is described that has been developed to increase the efficiency of finding the global minimum energy isomers for nanoalloy clusters. The GA is optimized for the example Pt12Pd12, with specific investigation of: the effect of biasing the initial population by seeding; the effect of removing specified clusters from the population ("predation"); and the effect of varying the type of mutation operator applied. These changes are found to significantly enhance the efficiency of the GA, which is subsequently demonstrated by the application of the best strategy to a new cluster, namely Pt19Pd19.  相似文献   
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Rabti  Amal  Zayani  Riham  Meftah  Marwa  Salhi  Imed  Raouafi  Noureddine 《Mikrochimica acta》2020,187(11):1-24
Microchimica Acta - This review (with 106 references) summarizes the latest progress in the synthesis, properties and biomedical applications of gold nanotubes (AuNTs). Following an introduction...  相似文献   
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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   
68.
We report experimental observation of passive harmonic mode locking (HML) in which the basic pattern is a soliton crystal. Several crystal states were generated from an initial large bound state by increasing the pump power. The soliton crystals are identical and progressively span along the cavity to finally take a regular spacing leading to HML of solitons crystal.  相似文献   
69.
The magnetic properties of Ni/Pd multilayers, prepared by sequential evaporation in ultrahigh vacuum, have been studied. The Ni thickness dependence of the magnetization and magnetic anisotropy is discussed. The temperature dependence of the spontaneous magnetization is well described by a T3/2 law in all multilayers. A spin-wave theory has been used to explain the temperature dependence of the spontaneous magnetization, and the approximate values for the exchange interactions for various Ni layer thicknesses have been obtained.  相似文献   
70.
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   
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