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Mg-Ni THIN FILM-A POTENTIAL NEGATIVE ELECTrODE FOr NIKEL-METAL HYDrIDE BATTErY

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Acta Metallurgica Sinica(English Letters) 2003年第3期16卷 226-230页

作者： L.z.Ouyang C.Y.Chung M.Q.zeng H.Wang M.zhu College of Mechanical Engineering South China University of TechnologyGuangzhou 510641China Department of Physics and Material Science City University of Hong Kong83 Tat Chee AvenueKowloon Hong KongDepartment of Physics and Material Science City University of Hong Kong83 Tat Chee Avenue Kowloon Hong Kong College of Mechanical EngineeringSouth China University of TechnologyGuangzhou 510641ChinaCollege of Mechanical EngineeringSouth China University of TechnologyGuangzhou 510641ChinaCollege of Mechanical EngineeringSouth China University of TechnologyGuangzhou 510641China

Mg-Ni thin films for nickel-metal hydride (Ni-MH) battery negative electrode were prepared on three different substrates by using magnetron sputtering with compacted Ni and Mg mixture powder. The microstructure of Mg-Ni thin films deposited on the glass and the Ni foil substrate respectively was studied by X-ray diffraction (XrD) and scanning electron microscopy (SEM). The results show that the Mg-Ni thin films were in amorphous structure and the composition of the thin film was homogeneous. Electrochemical measurement show the discharge capacity of the thin film negative electrode deposited on the foam Ni substrate was 284.8mAh/g in 6M alkaline electrolyte and the internal resistance was much lower than that of the electrode prepared by the ball-milled powder during the charge-discharge cycle.

关键词： magnetron sputtering Mg-Ni thin film Ni-MH battery

Various Expressions for Modulus of random Convexity

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Acta Mathematica Sinica,English Series 2013年第2期29卷 263-280页

作者： Xiao Lin zeng College of Mathematics and Statistics Chongqing Technology and Business University

We first prove various kinds of expressions for modulus of random convexity by using an L^0（F, r）-valued function＇s intermediate value theorem and the well known Hahn-Banach theorem for almost surely bounded random linear functionals, then establish some basic properties including continuity for modulus of random convexity. In particular, we express the modulus of random convexity of a special random normed module L^0（F, X） derived from a normed space X by the classical modulus of convexity of X.

关键词： random normed module modulus of random convexity Hahn-Banach theorem for almostsurely bounded random linear functionals

Horseshoes for Anosov Systems on Fibers Driven by an Equicontinuous System

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Acta Mathematica Sinica,English Series 2022年第1期38卷 281-290页

作者： Wen HUANG zeng LIAN School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026P.R.China College of Mathematical Sciences Sichuan UniversityChengdu 610016P.R.China

In this paper,we construct random horseshoes of Anosov systems driven by an equicontinuous system based on an ergodic measure with positive entropy.

关键词： random horseshoe Anosov diffeomorphism entropy

STUDY ON COMPOSITION, MICrOSTrUCTUrE AND HArDNESS OF DLC FILMS BY VCAD

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Acta Metallurgica Sinica(English Letters) 2003年第4期16卷 271-275页

作者： L.Chen z.Y.Liu D.C.zeng W.Q.Qiu z.H.Yuan S.S.Lin H.J.Hou InstituteofMaterialsScience&Technology CollegeofMechanicalEngineeringSouthChinaUniversityofTechnologyGuangzhou510640China GuangzhouresearchInstituteofNon-FerrousMetals Guangzhou510651ChinaManuscriptreceived25November2002

DLC super-hard films have been deposited on the substrates of single crystalline Si, pure Ti and stainless steel 18-8 by a method of vacuum cathode arc deposition (VCAD). The composition, microstructure and micro-hardness of the films have been studied in this paper. The results indicate that hardness of the DLC films is different on the different substrates. Hardness of the films increases with decreasing in surface roughness of the films. The maximum value of micro-hardness belongs to the DLC films deposited under the hydrogen pressure of 0.35Pa and the negative bias of 100V.

关键词： DLC films vacuum cathode arc deposition micro-hardness

reducing metal artifacts by restricting negative pixels

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Visual Computing for Industry,Biomedicine,and Art 2021年第1期4卷 142-151页

作者： Gengsheng L.zeng Megan zeng Department of Computer Science Utah Valley UniversityOremUT 84058USA Department of radiology and Imaging Sciences University of UtahSalt Lake CityUT 84108USA Department of Electrical Engineering and Computer Science University of California at BerkeleyBerkeleyCA 94720USA

When the object contains metals,its x-ray computed tomography(CT)images are normally affected by streaking *** artifacts are mainly caused by the x-ray beam hardening effects,which deviate the measurements from their true *** interesting observation of the metal artifacts is that certain regions of the metal artifacts often appear as negative pixel *** novel idea in this paper is to set up an objective function that restricts the negative pixel values in the *** must point out that the naïve idea of setting the negative pixel values in the reconstructed image to zero does not give the same *** paper proposes an iterative algorithm to optimize this objective function,and the unknowns are the metal affected *** the metal affected projections are estimated,the filtered backprojection algorithm is used to reconstruct the final *** paper applies the proposed algorithm to some airport bag CT *** bags all contain unknown metallic *** metal artifacts are effectively reduced by the proposed algorithm.

关键词： Filtered backprojection image reconstruction Iterative algorithm Metal artifact reduction Objective function X-ray computed tomography

3D rigid-Plastic Finite Element Analysis for Skew rolling Process of the Stepped Part

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Journal of Materials Science & Technology 2003年第Z1期19卷 38-40页

作者： Gang FANG Pan zeng Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Based on rigid-plastic finite element method, a skew rolling process of stepped part is simulated. Considering nodesaving and effective remeshing, the tetrahedron solid elements are used to discrete workpiece. The workpiece material adopts rigid-plastic model, where the flow stress is function of effective strain, effective strain rate and *** thermomechanical coupling is considered in the simulation. To model the spinning workpiece undergoing plastic deformation, a novel solution is presented and applied in this paper. The stress state in the workpiece and forming characteristic of skew rolling are analyzed. The forming load, including roller torque and forces in three directions are predicted. The above analyses are helpful to understanding of forming mechanisms and improving of process and die design.

关键词： FEM, Skew rolling, Stepped part, Spinning part, Fracture

Nonsolvable Groups with Three Nonlinear Irreducible Character Codegrees

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 173-178页

作者： Dongfang YANG Yu zeng Department of Mathematics Changshu Institute of TechnologyChangshu 215500JiangsuChina

For an irreducible characterχof a?nite group G,the codegree ofχis de-?ned as|G:ker(χ)|/χ(1).In this paper,the authors determine?nite nonsolvable groups with exactly three nonlinear irreducible character codegrees,... 详细信息

关键词： Character codegree Nonsolvable group

Ion-imprinted silica gel and its dynamic membrane for nickel ion removal from wastewaters

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Frontiers of Chemical Science and Engineering 2020年第6期14卷 1018-1028页

作者： Jiehui zeng Jianxian zeng Hu zhou Guoqing Liu zhengqiu Yuan Jian Jian School of Chemistry and Chemical Engineering Hunan University of Science and TechnologyXiangtan 411201China

An ion-imprinted sorbent(IIP)was prepared by using Ni^2+ as template,3-[2(2-aminoethylamino)ethylamino]propyl-trimethoxysilane as functional monomer,and silica gel as *** adsorption performance of IIP towards Ni^2+ was *** showed a higher adsorption capacity than that of non-imprinted sorbent,and it also exhibited high selectivity for Ni^2+ in the presence of Cu^2+ and zn^2+ ***,IIP was used to form a dynamic membrane onto the surface of ceramic membrane for treatment of electroplating wastewater containing Ni^2+.Compared with ceramic membrane,IIP dynamic membrane had much higher steady membrane flux,and also rejected Ni^2+ to obtain a lower concentration of Ni2+ in the permeate *** it is suitable for future practice applications.

关键词： ion-imprinted nickel ion dynamic membrane adsorption

Solid-state Circuit Breaker Based on Cascaded Normally-on SiC JFETs for Medium-voltage DC Distribution Networks

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Protection and Control of Modern Power Systems 2024年第2期9卷 32-46页

作者： Dong He Haohui zhou zheng Lan Wei Wang Jinhui zeng Xueping Yu z.John Shen Chongqing University of Posts and Telecommunications ChongqingChina Henan Polytechnic University JiaozuoChina College of Electrical and Information Engineering Hunan University of TechnologyZhuzhou 412007China Hunan University ChangshaChina College of Electrical and Information Engineering Hunan UniversityChangshaChina College of Electrical Engineering Three Gorges University rensselaer Polytechnic Institute TroyNYUSA

Solid-state circuit breakers(SSCBs)are critical components in the protection of medium-voltage DC distribution networks to facilitate arc-free,fast and reliable isolation of DC ***,limited by the capacity of a single semiconductor device,using semi-conductor-based SSCBs at high voltage is *** study presents the details of a 1.5 kV,63 A medi-um-voltage SSCB,composed primarily of a solid-state switch based on three cascaded normally-on silicon car-bide(SiC)junction field-effect transistors(JFETs)and a low-cost programmable gate drive *** and static voltage sharing among the cascaded SiC JFETs of the SSCB during fault isolation is realized using the pro-posed gate drive *** selection conditions for the key parameters of the SSCB gate driver are also ***,an improved pulse-width modulation cur-rent-limiting protection solution is proposed to identify the permanent overcurrent and transient inrush current associated with capacitive load startup in a DC distribu-tion *** the developed SSCB prototype and the fault test system,experimental results are obtained to validate the fault response performance of the *** Terms—Solid-state circuit breaker,DC distribu-tion network,SiC JFET,voltage balancing,inrush current.

关键词： Solid-state circuit breaker DC distribu-tion network SiC JFET voltage balancing inrush current