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Erwan Guillevic Mathieu Allix Jean-Luc Adam Xianping Fan 《Materials Research Bulletin》2010,45(4):448-3012
In this paper, we describe the preparation of Nd3+ doped glass-ceramics in the (GeS2)70-(Ga2S3)20-(CsCl)10 system. Neodymium has been introduced as metallic powder or incorporated as sulphide. Appropriate heat treatments of the base-glass lead to glass-ceramics with controllable crystal sizes that are transparent in the visible and infrared spectral ranges. X-ray diffraction as well as electron diffraction techniques were used to investigate the crystallization process. Differential scanning calorimetry indicates that neodymium ions are poor nucleating agents in this glass compared to erbium ions. Luminescence measurements were also performed and point out that although the ceramization process increases significantly the luminescence efficiency, the neodymium ions are only partially incorporated in the nanocrystals. 相似文献
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Thulium and Ytterbium-Doped Titanium Oxide Thin Films Deposited by Ultrasonic Spray Pyrolysis 总被引:1,自引:0,他引:1
Sébastien Forissier Hervé Roussel Patrick Chaudouet Antonio Pereira Jean-Luc Deschanvres Bernard Moine 《Journal of Thermal Spray Technology》2012,21(6):1263-1268
Thin films of thulium and ytterbium-doped titanium oxide were grown by metal-organic spray pyrolysis deposition from titanium(IV)oxide bis(acetylacetonate), thulium(III) tris(2,2,6,6-tetramethyl-3,5-heptanedionate) and ytterbium(III) tris(acetylacetonate). Deposition temperatures have been investigated from 300 to 600 °C. Films have been studied regarding their crystallinity and doping quality. Structural and composition characterisations of TiO2:Tm,Yb were performed by electron microprobe, x-ray diffraction, and Fourier transform infrared spectroscopy. The deposition rate can reach 0.8 μm/h. The anatase phase of TiO2 was obtained after synthesis at 400 °C or higher. Organic contamination at low deposition temperature is eliminated by annealing treatments. 相似文献
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This paper focuses on the notion of suitable weak solutions for the three-dimensional incompressible Navier-Stokes equations
and discusses the relevance of this notion to Computational Fluid Dynamics. The purpose of the paper is twofold (i) to recall
basic mathematical properties of the three-dimensional incompressible Navier-Stokes equations and to show how they might relate
to LES (ii) to introduce an entropy viscosity technique based on the notion of suitable weak solution and to illustrate numerically
this concept. 相似文献
48.
Zhanbing He Chang Seok Lee Jean-Luc Maurice Didier Pribat Paul Haghi-Ashtiani Costel Sorin Cojocaru 《Carbon》2011,49(14):4710-4718
Plasma-enhanced chemical vapor deposition, without a nickel-containing gaseous precursor, was used to synthesize continuous nickel (Ni) nanorods inside the hollow cavity of carbon nanofibers (CNFs), thus forming vertically aligned Ni/CNF core/shell structures. Scanning and transmission electron microscopic images indicate that the elongated Ni nanorods originate from the catalyst particles at the tips of the CNFs and that their formation is due to the effect of extrusion induced by the compressive force of the graphene layers during growth. Different from previous work, each vertically-aligned core/shell structure reported is totally isolated from its neighbors. Continuous Ni nanorods are found to separate into smaller ones with increasing growth time, which was ascribed to (i) the limited amount of Ni available in the tip of the CNF, (ii) the polycrystalline nature of the Ni nanorods and (iii) the combined effects of the compressive stresses on the side of the Ni nanorods and of the tensile stress along their axis. 相似文献
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Examines the male sex role and (1) its effects on men's physical and mental health and (2) the associated obstacles for men in seeking and using psychological services. A psychoeducational structured-group program for men illustrates how psychological services might be designed to make them more accessible and useful to men. R. F. Levant and G. F. Doyle's (see record 1983-28490-001) empirical evaluation of the group (The Fatherhood Course) is briefly discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Patrick Ginet Claude Lucat Francis Ménil Jean-Luc Battaglia 《International Journal of Applied Ceramic Technology》2007,4(5):423-427
A metallic electrothermal microactuator has been fabricated with screen-printing technology based on a sacrificial layer process. The actuator, printed on a standard 96% alumina, consists of two linked copper beams of different widths partially suspended above the substrate to which they are anchored. Energy-dispersive X-rays analyses demonstrate the harmlessness of the process with regard to the metallic layer. While increasing DC voltage between both anchors of the electrothermal microactuator, the deflection is optically measured using a calibrated CCD camera. The temperature distribution measured with an infrared camera in the actuator compares well with that calculated with finite element simulations. 相似文献