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Performance of Electric Double Layer Capacitors using Active Carbons Prepared from Petroleum Coke by KOH and Vapor Re-Etching

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Journal of Materials Science & Technology 2003年第3期19卷 265-269页

作者： Xiaofeng WANG, Dazhi WANG Ji LIANGDepartment of mechanical Engineering, Tsinghua University, Beijing 100084, China Tsinghua Univ Dept Mech Engn Beijing 100084 Peoples R China

The electrochemical storage of energy in a special kind of active carbon materials used as capacitor electrodes is considered. Petroleum coke was used for preparation of carbons with different porosities by KOH and vapor etching with catalysis of FeCI3 in turn. Carbon electrodes were fabricated and used as electrodes of double layer capacitors. Nitrogen adsorption was used to characterize the porous structure of the carbons. The electrochemical performance of the capacitors in 6 mol/L KOH was investigated with constant current charge and discharge experiments. A specific capacitance larger than 160 F/g was achieved with an electrode composed of 75% active carbon with a specific surface area of 1180 m2/g and 20% graphite as conductive agent. Evaluation of capacitor performance was conducted by different techniques, e.g. voltammetry and impedance spectroscopy. Characteristics of the capacitor were also discussed. A hybrid power source consisting of nickel- hydrogen and double layer capacitor was demonstrated by powering successfully a simulated power load encountered in communication equipment.

关键词： Activated carbon Re-etching Double layer capacitor Supercapacitor

Experimental Study about Activated Water Generated by the Electro-hydraulic Impulse Strengthening the mechanical Performance of Concrete

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Journal of Materials Science & Technology 2002年第4期18卷 290-292页

作者： Shijin ZHANG, Zhenfang LIAO and Changlin YANGCollege of mechanical Engineering, Chongqing University, Chongqing 400044, China Chongqing Univ Coll Mech Engn Chongqing 400044 Peoples R China

On the basis of a great number of experiments, it is proved that the strength of concrete is improved greatly when it is mixed with activated water produced by the electro-hydraulic impulse. With the proper parameters, the compression strength of concrete can be increased by 45%. The reason for improvement of concrete strength by using activated water is discussed from the aspect of the structure of molecule.

关键词： Concrete Electro-hydraulic impulse Activated waterx

Structure and Magnetic Properties of HoFe_(12-x) Mn_x Compounds

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Journal of Rare Earths 2001年第4期19卷 311-314页

作者：盛晓波林萍华 SE Univ Dept Mech Engn Nanjing 210096 Peoples R China

The effect of substitution of Mn on the structure and magnetic properties of HoFe 12- x Mn x (x =2 0, 3 0, 4 0 and 5 0) compounds was investigated. All the HoFe 12x Mn x compounds studied crystallize in ThMn 12 type of structure. The lattice constants and unit cell volume increase monotonously with increasing Mn concentration. The Curie temperature and the moments of the transition metal sublattice of HoFe 12- x Mn x compounds decrease monotonously with increasing Mn content. A minimum appears at x =3 0 in the Mn concentration dependence of the saturation magnetization of HoFe 12- x Mn x compounds. A compensation point appears in the M(t) curve of the compound with x =4 0. The mean field constant n RT of HoFe 9Mn 3 was calculated.

关键词： rare earths magnetic materials intermetallic compounds ThMn 12 structure

A NOVEL MODIFICATION TECHNIQUE FOR METAL SURFACE

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Journal of Wuhan University of Technology(Materials Science) 1996年第1期11卷 28-35页

作者：聂学渊郝庆恺卫家楣 WUHAN UNIV TECHNOL DEPT MECH ENGNWUHAN 430070PEOPLES R CHINA NANJING UNIV FORESTRY DEPT MECH ENGNNANJING 210037JIANGSUPEOPLES R CHINA

A novel solution-are discharge surface modification technique has been introduced in this paper,ln this modification technique, the speed of mass transport in surface and diffusion Layer is much higher than that of other ways, such as ion implantation, PVD, CVD, PCVD, glow discharge plasma treatment, etc. The solution-arc discharge plasma belongs to a plasma in high air pressure. Its cathode electric field, electric charge density and current density are much larger than those of Low temperature plasma. The voltage-current characteristic has been measured. mechanical and electrochemical properties of some steel treated with solution-arc discharge have been studied. As to the mechanism of this technique, an analysis has been given.

关键词： modification technique ion implantation solution-arc discharge plasma

A PERTURBATION BOUNDARY INTEGRAL EQUATION METHOD FOR ANALYSIS OF INTERACTION BETWEEN FOUNDATION AND NONLINEAR ROCK AND SOIL MEDIUM

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Acta mechanica Solida Sinica 1998年第1期11卷 72-83页

作者： Tao Weiming Cao Zhiyuan Sun Jun Zhejiang Univ Dept Mech Hangzhou 310027 Peoples R China Tongji Univ Dept Engn Mech & Technol Shanghai 200092 Peoples R China

A scheme is developed for analysing the interaction between afoundation and a nonlin- ear rock and soil medium, in which thefoundation is considered as a linear elastic body and a typicalboundary integral equation method (BIEM) is employed. On the basis oftaking the nonlinear proper- ties of the medium into account, aperturbation BIEM is developed. The fundamental equations for thenonlinear coupling analysis are formulated, and typical problems aresolved and discussed by the pre- sent method.

关键词： nonlinear foundation rock and soil medium

Experimental Study on Friction Reducing and Anti Wear Property of a Water-Based Lubricant with Polyether Added

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稀有金属材料与工程 2012年第S1期41卷 276-279页

作者： Zhang Chaohui Liu Sisi Liu Junming Beijing Jiaotong Univ Sch Mech Elect & Control Engn Beijing 100044 Peoples R China

The wear behaviors of steel-steel pair on condition of a water-based lubricant with copolymer of acylamino polyoxyethylene polyoxypropylene ether(KE-1)included as additives are investigated with the help of the universal *** on friction and wear are carried *** a reference,some tests with pure water are also performed for *** results show that the prepared water-based lubricant has a good effect on the characteristics associated with friction reducing and anti-wear processes,which lay some credence to its utilization in practical industrial tribo-systems.

关键词： acylamino-polyoxyethylene-polyoxypropylene-ether water-based lubricant anti-wear property

Analysis on Influence Factors of Real-time Identification of Neural Network in Sheet Intelligent Bending

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稀有金属材料与工程 2011年第S3期40卷 14-18页

作者： Su Chunjian, Zhang Guangheng, Guo Sumin Shandong University of Science and Technology, Qingdao 266510, China Shandong Univ Sci & Technol Coll Mech & Elect Engn Qingdao 266510 Peoples R China

The scheme of intelligent control system of cap-bending has been advanced in this paper using the neural network technology, based on the prominent problem that bending springback difficult to control accurately during the forming process of cap-bending. The key technology of real-time identification for material performance parameter and friction coefficient was researched, and the back-propagation neural network of real-time identification for material performance parameters and friction coefficient was established, which can real-time identify the needed material performance parameters through the real-time monitoring variable. Factors that affecting recognition results of neural network model were analyzed, such as influences of the selection of the sample date and the algorithm for identification result. Factors affecting neural network generalization ability were discussed, such as influences of the selection of the sample date and the node number of the hidden layer for generalization ability. The results provide a guarantee for improving the convergence accuracy and the generalization ability of network, and provide a basis for the building of intelligent bending control of network model.

关键词： sheet bending intelligent control real-time identification influence factor

HIGHER ORDER ASYMPTOTIC FIELDS AT THE TIP OF A SHARP V-NOTCH IN A POWER-HARDENING MATERIAL

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Acta mechanica Solida Sinica 2002年第2期15卷 102-110页

作者： Wang Weiwei Kuang Zhenbang Shanghai Jiao Tong Univ Dept Engn Mech Shanghai 200240 Peoples R China

The higher order asymptotic fields at the tip of a sharp V-notchin a power-hardening material for plane strain problem of Mode I arederived. The order hierarchy in powers of r for various hardeningexponents n and notch angles β is obtained. The angulardistributions of stress for several cases are plotted. Theself-similarity behavior between the higher order terms is *** is found that the terms with higher Order can be neglected for theV-notch angle β>45°.

关键词： asymptotic V-notch higher order terms power-hardening

THE INTERACTION BETWEEN CRACK AND ELECTRIC DIPOLE OF PIEZOELECTRICITY

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Acta mechanica Solida Sinica 2000年第4期13卷 283-289页

作者： Wang Jiwei Kuang Zhenbang Shanghai Jiao Tong Univ Dept Engn Mech Shanghai 200240 Peoples R China

Discrete dipoles located near the crack tip play an important rolein nonlinear electric field induced fracture of piezoelectricceramics. A physico-mathematical model of dipole is constructed oftwo gen- eralized concentrated piezoelectric forces with equaldensity and opposite sign. The interaction between crack and electricdipole in piezoelectricity is analyzed. The closed form solutions,including those for stress and electric displacement, crack openingdisplacement and electric potential, are obtained. The function ofpi- ezoelectric anisotropic direction, p_α(θ)=cosθ+p_αsinθ, canbe used to express the influence of a dipole's direction. In the casethat a dipole locates near crack tip, the piezoelectric stressintensity factor is a power function with -3/2 index of the distancebetween dipole and crack tip.

关键词： piezoelectricity dipole stress intensity factor