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Rare Metals 2008年第3期27卷 257-260页

作者： HUANG Yong WANG Yingjun NING Chengyun NAN Kaihui HAN Yong College of Materials Science and Engineering South China University of Technology Guangzhou 510641 China Key Laboratory of SpeciaUy Functional Materials Ministry of Education of China Guangzhou 510640 China State Key Laboratory for Mechanical Behavior of Materials Xi＇an Jiaotong University Xi ＇an 710049 China

A porous cerium-containing hydroxyapatite coating on commercially pure titanium was prepared by micro-arc oxidation （MAO） in an electrolytic solution containing calcium acetate, p-glycerol phosphate disodium salt pentahydrate （β-GP）, and cerium nitrate. The thickness, phase, composition morphology, and biocompatibility of the oxide coating were characterized by X-ray diffraction （XRD）, electron probe microanalysis （EPMA）, scanning electron microscopy （SEM） with energy dispersive X-ray spectrometer （EDS）, and cell culture. The thickness of the MAO film is about 15-25 ~tm, and the coating is porous and uneven, without any apparent interface to the titanium substrates. The results of XRD and EDS show that the porous coating is made up of hydroxyapatite （HA） film containing Ce. The favorable osteoblast cell affinity makes the Ce-HA film have a good biocompatibility. The Ce-HA film is expected to have significant medical applications as dental implants and artificial bone joints.

关键词： surface cerium hydroxyapatite coating micro-arc oxidation titanium porosity

A Direct Algorithm for Solving Singular LQ Optimal Control Problems

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A Direct Algorithm for Solving Singular LQ Optimal Control P...

Investigation of hemin as non-precious metal electrocatalyst for oxygen reduction reaction

第25届中国控制会议

作者： Zhang Pingjian, Xi Jianqing School of Computer Science and technology, south china university of technology, Guangzhou 510641

＜正＞Considered in this paper are the singular linear quadratic optimal control problems. A direct, constructive algorithm for solving this kind of problems is proposed. Compared to existing iterative algorithms, the new one terminates in finite steps and can obtain an analytic form for the value function. Compared to geometric approaches, the transformations involved in the new algorithm are straightforward and easy to apply. Numerical experiments demonstrate the validity of the proposed direct algorithm.

关键词： Singular controls LQ optimal control Direct algorithm

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Investigation of hemin as non-precious metal electrocatalyst...

New Controller Architecture Based on Dual Youla Parameterization

第七届中国功能材料及其应用学术会议

作者： LIANG Zhen-xing (School of Chemistry and Chemical Engineering,south china university of technology, Guangzhou 510641,china)

Hemin,a natural porphyrinatoiron complex,has been extensively investigated as the low-cost het-erocatalyst for various applications,including the organic synthesis,the electrochemical reduction of uranium, nitrite,nitric oxide,hydrogen peroxide,carbon dioxide and the oxidation of CO and *** this work,hemin is investigated as the non-precious metal electrocatalyst for oxygen reduction reaction,and the effect of the heat treatment on hemin is further ***/C shows poor performance in acid electrolyte but decent performance in alkaline *** heat treatment,hemin/C shows increased porosity and improved performance in both acid and alkaline ***,the pyrolysed hemin/C catalyst yields similar performance for the oxygen reduction reaction to the commercial Pt/C catalyst in alkaline *** inspiring finding makes it a promising non-precious metal electrocatalyst in fuel cells.

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Progress in study on metalloporphyrin mimicking metalloenzymes

第三十届中国控制会议

作者： XIE Wei College of Automation Science and technology,south china university of technology,Guangzhou 510641,P.R.china

＜正＞A new feedback controller architecture is proposed based on Dual Youla *** main feature of the controller architecture is that command tracking performance and external disturbance rejection may be done separately. First,a nominal controller can be considered for external disturbance ***,according to the left coprime factorization of the nominal controller,a dual Youla parameter can be designed to find an appropriate plant to guarantee the command tracking performance.

关键词： Robust Control Dual Youla Parameterization Controller Design

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Progress in Natural Science:Materials International 2002年第5期 3-12页

作者： JI Liangnian , PENG Xiaobin and HUANG Jinwang( Department of Chemistry, Zhongshan university, Guangzhou 510275,china Department of Applied Chemistry, south china university of technology, Guangzhou 510641, china) Department of Chemistry，Zhongshan university，Guangzhou 510275，china Department of Applied Chemistry，south china university of technology，Guangzhou 510641，china

The development of research on metalloporphyrins, which are used as model compounds for some metalloenzymes, is reviewed, including the survey of oxygen binding of heme, the catalytic oxidation of cytochrome P450, the... 详细信息

关键词： metalloporphyrins metalloenzymes model compound.

Experimental Investigation on Viscosity of Cu-H_2O Nanofluids

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Journal of Wuhan university of technology(Materials Science) 2009年第1期24卷 48-52页

作者：李新芳 Department of Packaging & Printing Zhongshan Torch Vocation and Technology College

A procedure for preparing a nanofluid that a solid-liquid composite material consists of solid nanoparticles with sizes typically of 1-100 nm suspended in liquid was proposed. By means of the procedure, Cu-H2O nanofluids with and without dispersant were prepared, whose sediment pho-tographs and particle size distribution were given to illustrate the stability and evenness of suspension with dispersant. The viscosity of Cu-H2O nanofluid was measured using capillary viscometers. The mass fractions（w） of copper nanoparticles in the experiment varied between 0.04% and 0.16% with the temperature range of 30-70 ℃. The experimental results show that the temperature and SDBS concentration are the major factors affecting the viscosity of the nano-copper suspensions, while the effect of the mass fraction of Cu on the viscosity is not as obvious as that of the temperature and SDBS dispersant for the mass fraction chosen in the experiment. The apparent viscosity of the copper nano-suspensions decreases with the temperature increase, and increases slightly with the increase of the mass fraction of SDBS dispersant, and almost keeps invariability with increasing the mass fraction of Cu. The influence of SDBS concentration on the viscosity of nano-suspension was relatively large comparing with that of the nanoparticle concentration.

关键词： nano-Cu/water suspension SDBS kinematic viscosity capillary viscometer

光子-玻色子元激发耦合激光模型的准周期自脉冲和混沌状态

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中国激光 1998年第6期25卷 533-538页

作者：何明高欧发广东工业大学数理系华南理工大学应用物理系

简化并用计算机求解了经过改进后的光子－玻色子元激发非线性耦合激光模型的动力学方程，并对所得到的包括梯形和矩形准周期自脉冲、尖峰自脉冲、零维和一维吸引子以及阵发性混沌等一系列有趣的现象进行了讨论和研究。

关键词：非线性光学玻色子自脉冲混沌光子激光模型

Generation of Laser Light via Ultrasonic Four-wave Mixing

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Chinese Journal of Lasers 2001年第2期 62-69页

作者： OU Fa (Department of Applied Physics, south china university of technology, Guangzhou 510641, china) WU Fugen HE Minggao (Department of Applied Physics, Guangdong university of technology, Guangzhou 510090, china)

On the basis of the interaction between phonons in ionic crystals with anharmonic lattice vibration, we present a laser model on acoustic nondegenerate four wave mixing. Two beams of high frequency ultrasound, incident on the acoustic cavity fulfilled with the medium of ionic crystal, play the role of pumping and one of the two side band modes of the pumping frequency as an acoustic signal mode has a strong interaction with the optical cavity mode, the coupling out of which will be the light (far infrared) output of a laser. The problem is treated with quantum mechanics. The theory shows that there is the threshold phenomenon as usual lasers and a so called “phase matching” condition is derived, which should be satisfied for stability of the system.

关键词： acoustic four wave mixing laser anharmonicity of the ionic lattice

Ultrasonic generation via direct interaction between photons and phonons in anharmonic lattice of ionic crystals

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Chinese Journal of Acoustics 2000年第2期19卷 182-191页

作者： OU Fa (Department of Applied Physics, south china university of technology Guangzhou 510641) WU Fugen HE Minggao (Physics Department, Guangdong university of technology Guangzhou 510090) LIU Cuihong (Physics Department, Guangzhou Teachers’College Guangzh

A theory of ultrasonic generation via direct interaction of transverse optic (TO) phonons with photons in anharmonic lattice of ionic crystals is presented. There are two methods of supplying light energy for the excitation of TO lattice wave as a high frequency ultrasound: (A) incident light comes from the source outside the cavity? fulfilled with ionic crystal medium, (B) photon mode of the cavity possesses the gain of amplification by stimulated radiation of active atoms doping in the medium. More attention is drawn to the case (B). The working system of case (B), as a mixture of lasing action and ultrasonic generation, has the threshold phenomena like usual laser. And the linear stability analysis shows that the nonlineax phonon-photon coupling and the interaction among phonons themselves, both of which reflect the anharmonicity of lattice vibration, are necessary to the stable ultrasonic output. So this laser-ultrasonic generation mixture would be also a measure to investigate the lattice-dynamic nonlinearity and correlated electromagnetic properties of ionic crystals.

关键词： Ultrasonic generation via direct interaction between photons and phonons in anharmonic lattice of ionic crystals mode

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图书馆信息服务的发展趋势及思考

图书馆论坛 2003年第2期23卷 101-103页

作者：童丽娜华南理工大学图书馆广东广州510641

网络信息技术的不断发展使图书馆信息服务面临新的机遇和发展 ,本文就信息服务工作的现状及问题展开论述。

关键词：网络环境图书馆信息服务发展趋势用户培训网络信息资源建设数据库建设