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61.
Fabien Durand Ai-Hua Fan Andrei Yu. Khrennikov Dongdai Lin Franco Vivaldi Yuefei Wang 《P-Adic Numbers, Ultrametric Analysis, and Applications》2011,3(4):359-362
On the occasion of the 60th birthday of Professor Vladimir Sergeevich Anashin, we present a review of his significant scientific
research and related activities. 相似文献
62.
Jul M. Weeren 《Fresenius' Journal of Analytical Chemistry》1895,34(1):133-134
Ohne Zusammenfassung 相似文献
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Jul Meyer und J. Jannek 《Fresenius' Journal of Analytical Chemistry》1913,52(9):534-538
Ohne Zusammenfassung 相似文献
66.
Treyssède F 《The Journal of the Acoustical Society of America》2007,121(6):3398-3408
Steel multi-wire cables are widely employed in civil engineering. They are usually made of a straight core and one layer of helical wires. In order to detect material degradation, nondestructive evaluation methods based on ultrasonics are one of the most promising techniques. However, their use is complicated by the lack of accurate cable models. As a first step, the goal of this paper is to propose a numerical method for the study of elastic guided waves inside a single helical wire. A finite element (FE) technique is used based on the theory of wave propagation inside periodic structures. This method avoids the tedious writing of equilibrium equations in a curvilinear coordinate system yielding translational invariance along the helix centerline. Besides, no specific programming is needed inside a conventional FE code because it can be implemented as a postprocessing step of stiffness, mass and damping matrices. The convergence and accuracy of the proposed method are assessed by comparing FE results with Pochhammer-Chree solutions for the infinite isotropic cylinder. Dispersion curves for a typical helical waveguide are then obtained. In the low-frequency range, results are validated with a helical Timoshenko beam model. Some significant differences with the cylinder are observed. 相似文献
67.
We have successfully developed a high-energy, high-repetition rate Ti:sapphire laser system that delivers 33 J before compression at 0.1 Hz. The final booster amplifier is based on a 100 mm diameter Ti:sapphire crystal pumped with 72 J of energy in six beams delivered by three frequency-doubled high-repetition rate Nd:glass lasers. This system is, to the best of our knowledge, the first demonstrated petawatt class laser system running at a high repetition rate. 相似文献
68.
Chrystelle Neaime Dr. Carole Daiguebonne Dr. Guillaume Calvez Stéphane Freslon Dr. Kevin Bernot Dr. Fabien Grasset Dr. Stéphane Cordier Prof. Olivier Guillou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(48):17466-17473
Heteronuclear lanthanide‐based coordination polymers are microcrystalline powders, the luminescence properties of which can be precisely tuned by judicious choice of the rare‐earth ions. In this study, we demonstrate that such materials can also be obtained as stable solutions of nanoparticles in non‐toxic polyols. Bulk powders of the formula [Ln2?2xLn′2x(bdc)3 ? 4 H2O]∞ (where H2bdc denotes 1,4‐benzene‐dicarboxylic acid, 0≤x≤1, and Ln and Ln′ denote lanthanide ions of the series La to Tm plus Y) afford nanoparticles that have been characterized by dynamic light‐scattering (DLS) and transmission electron microscopy (TEM) measurements. Their luminescence properties are similar to those of the bulk materials. Stabilities versus time and versus dilution with another solvent have been studied. This study has revealed that it is possible to tune the size of the nanoparticles. This process offers a reliable means of synthesizing suspensions of nanoparticles with tunable luminescence properties and tunable size distributions in a green solvent (glycerol). The process is also extendable to other coordination polymers and other solvents (ethylene glycol, for example). It constitutes a new route for the facile solubilization of lanthanide‐based coordination polymers. 相似文献
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