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Investigation of 2.9 μm luminescence properties and energy transfer in Tm^(3+)/Dy^(3+) co-doped chalcohalide glasses

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Journal of Rare Earths 2011年第2期29卷 105-108页

作者：李忠秀徐铁峰沈祥戴世勋王训四聂秋华章向华 College of Information Science and Engineering Ningbo University College of Science Jiangxi Agricultural University laboratoire de Verres et Ceramiques Universitè de Rennes I

A series of chalcohalide glasses based on the composition of 0.9（Ge30Ga5Se65）-0.1CsI with different Tm3＋/Dy3＋-codoped ions concentrations were synthesized by melt-quenching *** absorption spectra and 2.9 μm mid-infrared fluorescence spectra of glass samples under 800 nm laser excitation were *** results showed that Tm3＋ was an efficient sensitizer,which could enhance the Dy3＋： 2.9 μm fluorescence intensity *** effective energy transfer between the two rare-earth ions were mainly attributed to the resonance energy transfer from Tm3＋：3F4 to Dy3＋：6H11/2 *** cross section of 2.9 μm mid-infrared luminescence was also investigated according to Judd-Ofelt theory,σe=2.51×10–20 cm2.

关键词： chalcohalide glasses luminescence properties energy transfer Tm3+/Dy3+ rare earths

In situ chemical fabrication of polyaniline/multi-walled carbon nanotubes composites as supports of Pt for methanol electrooxidation

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Science China Chemistry 2010年第9期53卷 2006-2014页

作者： GAL Jean-Yves UMR laboratoire Hydrosciences Maison des Sciences de l'Eau de MontpellierUniversite Montpellier Ⅱ

In this study,platinum(Pt)-polyaniline(PANI)/MWNTs catalysts were synthesized by two sequential ***,coreshell structural PANI/MWNTs composites were fabricated by in-situ chemical oxidation polymerization,in which MWNTs act as the core and PANI as the ***,Pt particles were deposited on the PANI/MWNTs composites by a chemical reduction *** morphology and constitution of the products were characterized by FT IR,scanning electron microscopy,transmission electron microscopy and *** was observed that the Pt particles were smaller in size and more uniformly distributed on these composite supports than those on the reference,pure MWNT *** results showed higher Pt(111) content in the catalyst deposited on PANI/MWNTs supports than that on *** cyclic voltammeter(CV) tests demonstrated that the electrode modified by Pt-PANI/MWNTs ternary composite catalyst showed a higher catalytic stability than Pt-MWNT binary catalyst did,due to the synergic interaction between Pt and the composite support.

关键词： polyaniline multi-walled carbon nanotubes in situ polymerization methanol electrooxidation

Geology Along the Line from Yecheng to Shiquanhe and Tectonic Evolution of the Region Involved

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Acta Geologica Sinica(English Edition) 1995年第2期69卷 119-133页

作者： Ph.Matte P.Tapponnier laboratoire de Tectonique et Geocronologie U ST LMontpellierFranceInstitute de Physiqu

The geotraverse from Yecheng to Shiquanhe, on the western Qinghai-Tibet Plateau, totalling 1056 km in length, passes the western Kunlun Mountains and the eastern end of the Karakorum Mountains. The Chinese and French scientists made a joint investigation along the line from July to August, 1989. Based on the outcropped ophiolites, palaeontology, sedimentary facies, magmatism, tectonic deformation and metamorphism, the region involved may be divided from north to south into five terranes and four ophiolitic suture zones. The ages of these terranes have a tendency to become increasingly younger from north to south.

关键词： geotraverse ophiolite suture zone tectonic evolution Proto-Tethys

Characterization of organic matter deposited in the oriental zone from Moknine hypersaline environment, oriental Tunisia

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Chinese Journal Of Geochemistry 2005年第4期24卷 345-351页

作者： Raja CHAIRI Zohra EL ASMI DJELLOULI laboratoire de Ressources Minerales et Environnement Faculté des Sciences de Tunis 2092 Univ. Tunis El Manar Tunisie Laboratoire de Ressources Minerales et Environnement Faculté des Sciences de Tunis 2092 Univ. Tunis El Manar Tunisie

The geochemistry data show that the total organic carbon (TOC) contents are high in the surface sediments in the eastern part of the Moknine’s Sebkha. Low decreasing of organic matter (OM) with increasing depth indicates the good preservation of OM in modern sediments. “Lignite levels” inserted in the sand sequence and deposited at the edge and in the intermediate zone are considered as lithologic and organic markers. It is characterized by high TOC and poor hydrogen index (HI), indicating a higher plant origin and good preservation of OM in thin beds under anoxic condition.; In all samples low values of HI are typical for strong terrigenous input in the Sebkha. Gas chromatography (GC) of saturate fraction showed that OM in the border zone is provided from plants but in the central zone OM is a mixture of terrestrial fraction and little fraction from microalgae. The study of free lipids indicated that this environment was influenced by intense bacterial and microbial activities, as evidenced by the abundance of n-alkanes and nC-{18}-nC-{22}.

关键词：突尼斯地球化学有机物质褐煤地质条件

Optimised NSAIDs-loaded Biocompatible Nanoparticles

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Nano-Micro Letters 2010年第4期2卷 247-255页

作者： V.Gaelle ROULLIN Maaite CALLEWAERT Michael MOLINARI Franck deLAVOIE Aurelie SECONde Marie-Christine ANDRY Institut de Chimie Mole culaire de Reims CNRS UMR 6229UFR Pharmacie Reims laboratoire de Microscopies et d’Etudes des Nanostructures UFR des SciencesUniversitéde Reims Champagne-Ardenne laboratoire de Microscopie Electronique Analytique INSERM UMRS 92621 rue Clement Ader51685 Reims Cedex 2France

In this formulation study,biocompatible non steroidal anti-inflammatory(NSAIDs)-loaded nanoparticles were designed as models to be further integrated in a prosthesis surface functionalization.A modified spontaneous emulsion-solvent diffusion methodology was used to produce drug-loaded PLGA nanoparticles without any purification or solvent evaporation *** parameters,such as lactide/glycolide ratio,polymer concentration,solvent/non solvent ratio and non solvent phase,as well as the non ionic tensioactive P188 co-precipitation composition were systematically *** optimized formulation(mean size:145 nm,surface charge:-13 m V) was employed to encapsulate various amounts of NSAIDs in a simple and scalable *** drug release was characterized in vitro by a complete release for 48 *** results encourage upcoming preliminary steps for in vivo experiments of prosthesis surface functionalization.

关键词： Drug delivery systems(DDS) Biocompatible Emulsion-solvent diffusion method PLGA Glycofurol Non steroidal anti-inflammatory drugs(NSAIDs)

Calculation of CO_2, CH_4 and H_2S Solubilities in Aqueous Electrolyte Solution at High Pressure and High Temperature

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Journal of Thermal Science 1997年第4期6卷 251-259页

作者： Carrier Hervé Suyu Ye Lagourette Bernard Alliez Jacques Xans Pierre laboratoire Haute Pression Centre Universitaire de Recherche Scientifique Université de Pau Pau France

This paper reports an investigation into the characterisation of liquidaivapor electrolyte solutions at high pressure and high temperature. A procedure to enable calcuIations of methane, carbon dioxide and hydrogen sulphide solubilities in brines (0-6 m.) for temperature from 25 to 350℃ and for pressures from 1 to 1800 bar is presented. The model is based on Helgeson, Kirkham and Flowers modified equations of state (HKF) and on the semi-empirical interaction model introduced by Pitzer. HKF modified equations of state are used to calculate the reference fugacity of gas species, and the Pitzer ionic interaction model is used to calculate the activity coefficient of dissolved species (i.e. ionic or neutral).The efficiency of the combination of the two models is confirmed by several comparisons with data in the literature.

关键词： vapor-liquid equilibria solubility electrolytes solutions high temperature high pressure

Blockage and distortion effects on a vane-island type diffuser performance of centrifugal pumps for various flow rates

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排灌机械工程学报 2016年第12期34卷 1013-1021页

作者： SI Qiaorui DAZIN Antoine DUPONT Patrick ROUSSETTE Olivier BOIS Gérard National Research Center of Pumps Jiangsu University laboratoire de Mécanique de Lille (UMR CNRS 8107) Arts et Métiers ParisTech laboratoire de Mécanique de Lille(UMR CNRS 8107) Ecole Centrale de Lille

Experimental investigation of mean flow velocity and pressure inside the vane-island type diffuser passage of a test centrifugal pump model is presented.A directional three-hole probe was used to investigate hub-to-shroud flow properties at diffuser leading and trailing edge *** addition,the mid-section between suction and pressure sides along the diffuser passage was also *** these measurements were performed at five different flow *** flow structures at the inlet section of the diffuser and along with the passage were analyzed in detail,with a focus on the flow distribution and the pressure recovery evolution of different diffuser *** and distortion effects were analyzed by using existing published particle image velocimetry(PIV)measurements in the outer part of the impeller and around the diffuser throat in order to get a better understanding of the overall performances and local flow structures of such a diffuser *** results show that back flows occur on the shroud region from impeller exit plane up to the semi-vaneless part of the diffuser at low flow *** blockage effects combining with blade thickness geometrical blockage tend to diminish the effects of theoretical high positive *** high flow rates,negative incidence effects induce high local velocity on the pressure side of the diffuser just after the *** aerodynamic blockage associated with low flow distortions are found to have a beneficial effect on pressure recovery for low flow *** the contrary,high flow distortions are found for increased flow rates,resulting in a low pressure recovery inside the semi-vane less part of the diffuser and after the throat.

关键词： vane island diffuser flow structure pressure recovery three-hole probe particle image velocimetry

Periodic Solutions of Evolution Variational Inequalities—a Method of Guiding Functions

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Chinese Annals of Mathematics,Series B 2009年第3期30卷 261-272页

作者： Samir ADLY Daniel GOELEVEN Michel THRA Département de Math'ematiques et Informatique Laboratoire XLIM(Unité Mixte 6172 du CNRS)Université de Limoges123 Avenue A.Thomas87060 Limoges CedexFrance. laboratoire d' Informatique et de Mathématiques Université de La Réunion97400 Saint-DenisFrance.

This paper focuses on a part of the presentation given by the third author at the Shanghai Forum on Industrial and Applied Mathematics(Shanghai 2006).It is related to the existence of a periodic solution of evolution ... 详细信息

关键词： Variational inequality Differential inclusion Topological degree Guiding function Periodic solution

On a non-autonomous reaction-convection diffusion model to study the bacteria distribution in a river

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International Journal of Biomathematics 2017年第6期10卷 25-49页

作者： Imene Meriem Mostefaoui Ali Moussaoui laboratoire de Mathematiques Image et Applications Universite de La Rochelle Pdle Sciences et Technologies Avenue Michel Crepeau 17000 La Rochelle France laboratoire D'Analyse Non Lineaire et Mathematiques Appliquees Universite de Tlemcen Tlemcen Algeria laboratoire D'Analyse Non Lineaire et Mathematiques Appliquees departement de Mathematique Faculte des Sciences Universite de Tlemcen Tlemcen Algeria

In this paper, we propose a non-autonomous convection-reaction diffusion system （CDI） with a nonlinear reaction source function. This model refers to the quantification and the distribution of antibiotic resistant bacteria （ARB） in a river. The main contributions of this paper are：（i） the determination of the limit set of the system by applying the semigroups theory, it is shown that it is reduced to the solutions of the associated elliptic system （CDI）e, （ii） sufficient conditions for the existence of a positive solution of （CDI）e based on the Leray-Schauder＇s degree theory. Numerical simulations which support our theoretical analysis are also given.

关键词： Reaction-diffusion systems steady states problems degree theory semi-groups.