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Template-free Fabrication and Luminescent Characterization of Highly Uniform and Monodisperse Y_2O_2s:sm^(3+) Hollow submicrospheres

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Journal of Materials science & Technology 2012年第7期28卷 666-672页

作者： s.q. Deng Z.P. Xue Y.H. Yang q. Yang Y.L. Liu Department of Chemistry Jinan University Guangzhou 510632 China

Well dispersed and homogeneous Y2O2s：sm3＋ hollow submicrospheres were successfully achieved by a template- free solvothermal method combining with a postcalcining process. The crystalstructure and particle morphology were investigated by the X-ray diffraction （XRD）, Fourier transform infrared （FT-IR） spectra, scanning and transmission electron microscopy （sEM and TEM）, respectively. A possible growth mechanism was proposed to reveal the formation process. Luminescence properties of the Y202s：sm3＋ long-lasting phosphor were an- alyzed by measuring the excitation spectra, emission spectra, afterglow decay curve and thermoluminescence curve. The excitation spectra indicated that the phosphor could be excited effectively by the ultraviolet-light emitting diode （UV-LED） or blue LED, and the emission spectra showed that the phosphor could emit red light from 600 to 650 nm.

关键词： Yttrium oxysulfide Hollow submicrosphere Luminescence Long-lasting phosphor

IMPROVEMENT OF CARBIDE MORPHOLOGY ANDMECHANICAL PROPERTIEs OF Cr12MoV sTEELs

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Acta Metallurgica sinica(English Letters) 2000年第5期13卷 1053-1058页

作者： Cui, X.H. Jiang, q.C. Wang, s.q. He, Z.M. sch. of Mat. sci. and Eng. Jilin Univ. of Technol. Changchun 130025 China

Compared with conventional cast Cr12MoV steel and forged Cr12MoV steels, carbide morphology and properties of modified cast Cr12MoV steels were investigated by performing hardness test, impact test, fracture toughness test, fatigue crack propagation test, metallographic examination and quantitatively metallographic analysis. The results indicate that the carbide morphology in modified cast steel is characterized by uniformly-distributed granular carbide, which is different from that of conventional cast steel, but similar to that of forged steel. the impact toughness of modified cast steel is distinctly increased to 12.75 J/cm2 from 6.8 J/cm2 in the conventional cast steel with networked carbide, because of carbide granulation. Furthermore, The fracture toughness and fatigue-crack-propagation threshold of modified cast steel are not only higher than that of the conventional cast steel, but also higher than that of the forged steels.

关键词： Alloys Carbides Mechanical properties Morphology

Heat transfer in a porous saturated wavy channel with asymmetric convective boundary conditions

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Journal of Central south University 2015年第1期22卷 392-401页

作者： q.Hussain s.Asghar T.Hayat A.Alsaedi Department of Mathematics COMSATS Institute of Information Technology Department of Mathematics Faculty of Science King Abdulaziz University Department of Mathematics Quaid-I-Azam University 45320

The viscous flow in a wavy channel with convective boundary conditions is investigated. The channel is filled with a porous viscous fluid. Two cases of equal and different external convection coefficients on the walls are taken into account. Effect of viscous dissipation is also considered. The governing equations are derived employing long wavelength and low Reynolds number approximations. Exact closed form solutions are obtained for the simplified equations. Important physical features for peristaltic flow caused by the wavy wave are pumping, trapping and heat transfer rate at the channel walls. These are discussed one by one in depth and detail through graphical illustrations. special attention has been given to the effects of convective boundary conditions. The results show that for Bi1≠Bi2, there exists a critical value of Brinkman number Brc at which the temperatures of both the walls become equal. And, for Bi1>Bi2 and Br>Brc, the temperature of the cold wall exceeds the temperature of hot wall.

关键词： peristalsis heat transfer porous medium convective boundary conditions

EFFECT OF MODIFICATION ON CARBIDE GRANULATION AND ITs MECHANIsM

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Acta Metallurgica sinica(English Letters) 1999年第2期12卷 167-172页

作者： Wang, s.q. Jiang, q.C. Cui, X.H. He, Z.M. Jilin Univ of Technology Changchun China

By the modification, network carbide is disconnected at 1100 degree C through uneven dissolution at higher energy places in carbide, where there is twin or lattice distortion, and is granulated at 1130 degree C through element diffusion. The stability of M//7C//3 carbide is decreased because of the modification reducing the segregation of Cr and Mo, thus the temperature, at which uneven dissolution of carbide commenced, is decreased. Also lattice distortion or defect such as twin in carbide is increased by the modification, which prompts widespread disconnections in carbide. In addition, the modification prompts element diffusion to accelerate the kinetics process of carbide granulation. (Edited author abstract) 6 Refs.

关键词： Carbides Chromium alloys Granulation Modification Morphology

solution of shallow-water equations using least-squares finite-element method

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Acta Mechanica sinica 2008年第5期24卷 523-532页

作者： s.J. Liang J,-H, tang M.-s. Wu Department of Marine Environmental Informatics National Taiwan Ocean UniversityKeelung 20224 Taiwan China Department of Bioenvironmental Engineering Chung-Yuan Christian University Chung-Li 32023 Taiwan China Department of Geographic Information systems Feng Chia University Taichung 40724 Taiwan China

A least-squares finite-element method （LsFEM） for the non-conservative shallow-water equations is presented. The model is capable of handling complex topography, steady and unsteady flows, subcritical and supercritical flows, and flows with smooth and sharp gradient changes. Advantages of the model include：（1） sources terms, such as the bottom slope, surface stresses and bed frictions, can be treated easily without any special treatment; （2） upwind scheme is no needed; （3） a single approximating space can be used for all variables, and its choice of approximating space is not subject to the Ladyzhenskaya-Babuska-Brezzi （LBB） condition; and （4） the resulting system of equations is symmetric and positive-definite （sPD） which can be solved efficiently with the preconditioned conjugate gradient method. The model is verified with flow over a bump, tide induced flow, and dam-break. Computed results are compared with analytic solutions or other numerical results, and show the model is conservative and accurate. The model is then used to simulate flow past a circular cylinder. Important flow charac-teristics, such as variation of water surface around the cylinder and vortex shedding behind the cylinder are investigated. Computed results compare well with experiment data and other numerical results.

关键词： Least-square finite-element method,shallow-water equations Dam-break Vortex shedding

3D－qsAR　sTUDY　ON　HUPERZINE　A　ANALOGs　WITH　MOLECULAR　MODELING　AND　COMPARATIVE　MOLECULAR　FIELD　ANALYsIs（COMFA）　METHODs

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Chinese Chemical Letters 1996年第3期7卷 253-256页

作者： Jiang, HL Chen, KX Chen, JZ tang, Y Wang, qM Li, q shen, X Ji, RY CHINEsE ACAD sCI SHANGHAI INST MAT MEDSHANGHAI 200031PEOPLES R CHINA

On the basis of conformational search for ten huperzine A analogs according to the structure ofAChE active site witll our approach BCsPL,we performed a 3D-qsAR analysis for these compounds usingmolecular modeling and CoMFA method. The calculation results can be used to explain the relationshipbetween the structUre properties and the activities.

关键词： qsAR sTUDY ON HUPERZINE ANALYsIs ANALOGs

Micro-sized and Nano-sized Fe_3O_4 Particles as Anode Materials for Lithium-ion Batteries

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Journal of Materials science & Technology 2011年第1期27卷 41-45页

作者： Y.X.Chen L.H.He P.J.shang q.L.tang Z.q.Liu H.B.Liu L.P.Zhou College of Materials science and Engineering Hunan UniversityChangsha 410082China shenyang National Laboratory for Materials science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Micro-sized（1030.3±178.4 nm） and nano-sized（50.4±8.0 nm） Fe3O4 particles have been fabricated through hydrogen thermal reduction of α-Fe2O3 particles synthesized by means of a hydrothermal *** morphology and microstructure of the micro-sized and the nano-sized Fe3O4 particles were characterized by X-ray diffraction,field-emission gun scanning electron microscopy,transmission electron microscopy and highresolution electron *** micro-sized Fe3O4 particles exhibit porous structure,while the nano-sized Fe3O4 particles are solid *** electrochemical performance was also *** nano-sized solid Fe3O4 particles exhibit gradual capacity fading with initial discharge capacity of 1083.1 mAhg-1 and reversible capacity retention of 32.6% over 50 ***,the micro-sized porous Fe3O4 particles display very stable capacity-cycling behavior,with initial discharge capacity of 887.5 mAhg-1 and charge capacity of 684.4 mAhg-1 at the 50th ***,77.1% of the reversible capacity can be maintained over 50 *** micro-sized porous Fe3O4 particles with facile synthesis,good cycling performance and high capacity retention are promising candidate as anode materials for high energy-density lithium-ion batteries.

关键词： Lithium-ion battery Fe3O4 Porous structure Anode materials

MOLECULAR　MECHANICAL　AND　qUANTUM　CHEMICAL　CALCULATION　ON　ACYLATION　REACTIVITY　FOR　1－（NITRO　sUBsTITUTED　ANILINO）－4－sUBsTITUTED－2，6－PIPERAZINEDIONEs

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Chinese Chemical Letters 1995年第8期6卷 691-694页

作者： Jiang, HL Li, q Chen, KX tang, Y shen, X Ji, RY Xie, YY Chinese Acad sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

Molecular mechanical and quantum chemical methods were used to calculate the conformational and electronic structures of the template molecules of (nitro substituted an ill no)-4 - sub st nut ed -2, 6 -piperazinediones, With the calculation results we explained the acylation reactivity of title compounds satisfactorily.

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Effects of Current stressing on shear Properties of sn-3.8Ag-0.7Cu solder Joints

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Journal of Materials science & Technology 2010年第8期26卷 737-742页

作者： X.J. Wang q.L. Zeng q.s. Zhu Z.G. Wang J.K. shang shenyang National Laboratory for Materials science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Materials science and Engineering University of Illinois at Urbana-Champaign Urbana IL 61801 USA

Effects of electromigration on microstructure, shear strength, and fracture behavior of solder joints were investigated by single-ball shear samples of eutectic sn-3.8Ag-0.7Cu （sAC） joined by Cu plates at two sides. The electromigration tests were conducted at a current density of about 1.1×10^3 A/cm2 and a working temperature of about 83℃. The results showed that the shear strength and flow stress decreased greatly after current stressing. such a decrease was associated with no significant loss of the fracture strain at short electromigration but a great reduction in the fracture strain after long-term current stressing. The variation of the fracture strain with the electromigration time was shown to result from the shift of the fracture surface from the center of the solder towards the intermetallic compound （IMC） interface at the cathode.

关键词： strength Fracture strain Voids solder