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Journal of materials science & {2. 1998年第1期14卷 20-24页

作者： Huaping XIONG (Dept. of materials science and {2., Jilin university of technology, Changchun 13002., china) Dept. of materials science and {2. Jilin University of Technology Changchun 130025 China

By using newly developed CuNi5~2.Ti16~2. B rapldly solidifled brazing filler the joining of Si3 N4/1.2.Cr-0.5Mo steel has been carried out with interlayer method. If employing the interlayer structure of steel (0.2.mm)/W (2.0 mm)/Ni(0.2.mm), the joint strength can be increased greatly compared with employing that of Ni/W/Ni, and the three point bend strength of the Joint shows the value of 2.1 MPa. The metallurgical behaviour at the interface between Si3N4 and the interlayer has been studied. It is found that Fe participated in the interfacial reactions between Si3N4 and the brazing filler at the Si3N4/steel (0.2.mm) interface and the compound Fe5Si3 was produced. However, since the reactions of Fe with the active Ti are weaker than those of Ni with Ti, the normal inter facial reactions were still assured at the interface of Si3N4/steel (0.2.mm) instead of Si3N4/Ni (0.2.mm), resulting in the improvement of the joint strength. The mechanism of the formation of Fe5Si3 is also discussed. Finally, some ideas to further ameliorate and simplify the interlayer structure are put forward.

关键词： Si Effect of Metallurgical Behaviour at the Interface between Ceramic and Interlayer on the Si3N4/1.2.Cr-0.5Mo Steel Joint Strength Ni Cr Mo

Carbonation Resistance of Sulphoaluminate Cement-based High Performance Concrete

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Journal of Wuhan university of technology({2. science) 2009年第4期24卷 663-666页

作者：张德成 school of materials {2. and engineering Wuhan University of Technology school of materials {2. and engineering University of Jinan

The influences of water/cement ratio and admixtures on carbonation resistance of sulphoaluminate cement-based high performance concrete （HPC） were investigated. The experimental results show that with the decreasing water/cement ratio, the carbonation depth of sulphoaluminate cement-based HPC is decreased remarkably, and the carbonation resistance capability is also improved with the adding admixtures. The morphologies and structure characteristics of sulphoaluminate cement hydration products before and after carbonation were analyzed using SEM and XRD. The analysis results reveal that the main hydration product of sulphoaluminate cement, that is ettringite （AFt）, decomposes after carbonation.

关键词： sulphoaluminate cement carbonation high performance concrete (HPC) admixture ettringite

PREDICTION ON THE THERMODYNAMIC PROPERTIES OF TERNARY LIQUID ALLOYS BY MODIFIED COORDINATION EQUATION

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 241-247页

作者： D.P. Tao school of materials and Metallurgical {2., Kunming university of science and technology, Kun-ming 650093, china Sch. of Mat. Eng. Kunming Univ. of Sci. and Technol. Kunming 650093 China

The coordination numbers in the Molecular Interaction Volume Model can be calcu-lated from the common physical quantities of pure matters.A significant advantage ofthe model lies in its ability to predict the thermodynamic properties of ternary liqmdalloys using only the binary infinite dilute activity coefficients,and the predicted values are in good agreement with the experimental data of ternary liquid alloys,whichshows that the model is reliable,convenient and economic.

关键词： thermodynamic property ternary liquid alloy molecular inter-action volume model modified coordination eguation

Melt-spun Al_(70-X)Si_(30)Mn_X (X=0,3,5,7,10) anode in lithium-ion batteries

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science china(Technological sciences) 2009年第8期52卷 2288-2294页

作者： SUN ZhanBo1, LI XuePeng1, WANG XiaoDong1, HU Qing1, ZHAO MingShu1, ZHU YaoMin2. LI Yan2.& SONG XiaoPing1 1 school of science, State Key Laboratory for Mechanical Behavior of {2., Xi’an Jiaotong university, Xi’an 710049, china 2.school of {2. science and engineering, Henan university of science and technology, Luoyang 471003, china 1. school of science State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University Xi’an 710049 China 2. school of materials science and engineering Henan University of Science and Technology Luoyang 471003 China

Al70-XSi30MnX (X=0, 3, 5, 7, 10, mol%) ribbons were prepared by melt spinning. A supersaturated solid solution of Si and Mn in fcc Al and some microstructures consisting of nano grains were obtained. Some alloys with nano-sized grains exhibited high discharge capacities and favorable cycle properties. The capacity of more than 400 mAh/g could be obtained in melt-spun Al67Si30Mn3 alloy after 2. cycles and more than 300 mAh/g after 40 cycles. Li/Si and Li/Al compounds in the anodes of pure Al and pure Si were not detected in Al-Si-Mn alloys inserted by Li. It is considered that the formation of the supersaturated solid solution and refinement of microstructures have prevented the alloys from the forming the compounds with superfluous Li. As a result, the electrochemical properties have been improved.

关键词： Al-Si-Mn alloy melt spinning microstructure electrochemical property

Effect of Fe metal on the growth of silicon oxide nanowires

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International Journal of Minerals,Metallurgy and materials 2009年第3期16卷 317-321页

作者： Wei-long Liu1), Shu-huei Hsieh1), Ching He Chen2., and Wen-jauh Chen3) 1) Department of materials science and {2., Formosa university, Yunlin 632. china Taipei 2. Department of materials {2., Pingtung university of science and technology, Pingtung 912. china Taipei 3) Graduate school of materials science, Yunlin university of science and technology, Yunlin 632. china Taipei [a]Department of materials science and {2. Formosa University Yunlin 632 China Taipei [b]Department of Materials Engineering Pingtung University of Science and Technology Pingtung 912 China Taipei [c]Graduate School of Materials Science Yunlin University of Science and Technology Yunlin 632 China Taipei

Silicon oxide (SiOx) nanowires are generally grown on Si substrate under the catalysis of Au in N2.atmosphere at elevated temperatures. Because the price of Au metal is quite high, Fe metal is then used to replace a part of Au for catalyzing the growth of SiOx nanowires. The results show that the Fe film can be used as the diffusion barrier of Au. SiOx nanowires are grown on Au/Fe/Si substrate at 1030°C. Under the catalysis of Fe/Au, the efficiency for the growth of SiOx nanowires is promoted.

关键词： silicon oxide nanowires Au catalyst Fe substitution Si substrate

Theorems for Testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied science school, {2. of science and technology Beijing, Beijing 100083, china) Applied science school University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat

A study on compressive shock wave propagation in metallic foams

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science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 279-287页

作者： WANG ZhiHua1,2.ZHANG YiFen2.REN HuiLan1 & ZHAO LongMao2.1 State Key Laboratory of Explosion science and technology,Beijing Institute of technology,Beijing 100081,china 2.Institute of Applied Mechanics and Biomedical engineering,taiyuan university of technology,taiyuan 03.024,china 1. State Key Laboratory of Explosion science and technology Beijing Institute of Technology Beijing 100081 China2. Institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology Taiyuan 030024 China

Metallic foam can dissipate a large amount of energy due to its relatively long stress plateau,which makes it widely applicable in the design of structural crashworthiness. However,in some experimental studies,stress enhancement has been observed when the specimens are subjected to intense impact loads,leading to severe damage to the objects being protected. This paper studies this phenomenon on a 2. mass-spring-bar model. With the model,a constitutive relationship of metal foam and corresponding loading and unloading criteria are presented; a nonlinear kinematics equilibrium equation is derived,where an explicit integra-tion algorithm is used to calculate the characteristic of the compressive shock wave propagation within the metallic foam; the effect of heterogeneous distribution of foam microstructures on the shock wave features is also included. The results reveal that under low impact pulses,considerable energy is dissipated during the progressive collapse of foam cells,which then reduces the crush of objects. When the pulse is sufficiently high,on the other hand,stress enhancement may take place,especially in the heterogeneous foams,where high peak stresses usually occur. The characteristics of compressive shock wave propagation in the foam and the magnitude and location of the peak stress produced are strongly dependent on the mechanical properties of the foam material,amplitude and period of the pulse,as well as the homogeneity of the microstructures. This research provides valuable insight into the reliability of the metallic foams used as a protective structure.

关键词： aluminum foam heterogeneous intensive pulse loading stress enhancement

Early Age Compressive Strength of Pastes by Electrical Resistivity Method and Maturity Method

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Journal of Wuhan university of technology({2. science) 2011年第5期26卷 983-989页

作者：肖莲珍 school of materials {2. and engineering Wuhan Institute of Technology

The compressive strength development of Portland cement pastes was investigated by the electrical resistivity method and the maturity *** experiments were carried out on the cement pastes with different water-cement ratios at different curing *** results show that the application of the maturity method has limitation to obtain the *** is found that both of the compressive strength and the electrical resistivity follow hyperbolic trend for all the *** hyperbolic equation of each mix is obtained to estimate the ultimate resistivity value which can probably be *** relationship between electrical resistivity and compressive strength of the cement pastes is established based on the test results and interpreted by the empirical Archie equation and a strength-porosity *** relationship between the electrical resistivity after temperature correction and the compressive strength was linear and independent of curing temperature and water-cement ratio.

关键词： electrical resistivity cement hydration compressive strength maturity method

Numerical simulations and experimental investigations on transverse effects of two-wave mixing in a photovoltaic photorefractive crystal

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science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 856-863页

作者： CAI Xin1,2.LIU JinSong1 & WANG ShengLie1 1 Wuhan National Laboratory for Optoelectronics,school of Optoelectronic science and {2.,Huazhong university of science and technology,Wuhan 430074,china 2.school of science,Wuhan university of technology,Wuhan 430070,china 1. Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China2. School of Science Wuhan University of Technology Wuhan 430070 China

The transverse effects of two Gauss waves mixing in a photovoltaic photorefractive crystal,i.e.,the dynamical evolutions of signal beam with different parameters,are traced numerically and *** the one-dimensional numerical simulations and two-dimensional experimental investigations show that the self-focusing effect of signal beam becomes more obvious as the intensity of pump beam and the angle between the signal and pump beams *** accordance with these results,the state of two Gaussian waves mixing is controllable.

关键词： numerical simulation experimental investigation two-wave mixing transverse effects Gaussian distribution

Three-dimensional elasticity solution of simple-supported rectangular plate on point supports, line supports and elastic foundation

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science china(Technological sciences) 2009年第3期52卷 584-589页

作者： XU YePeng1 & ZHOU Ding2.1 school of science, Nanjing {2. of science and technology, Nanjing 2.0094, china 2.College of Civil engineering, Nanjing {2. of technology, Nanjing 2.0009, china 1. school of science Nanjing University of Science and Technology Nanjing 210094 China 2. College of Civil engineering Nanjing University of Technology Nanjing 210009 China

This paper studies the bending of simple-supported rectangular plate on point supports, line supports and elastic foundation. On the basis of three-dimensional elasticity theory, the exact expressions of the displacement functions, which satisfy the governing differential equations and the simply supported boundary conditions at four edges of the plate, are analytically derived. The reaction forces of the in- termediate supports are regarded as the unknown external forces acting on the lower surface of the plate. The unknown coefficients are then determined by the boundary conditions on the upper and lower surfaces of the plate. Comparing the numerical results obtained from the proposed method to those obtained from Kirchhoff plate theory, Mindlin plate theory and those obtained from the commer- cial finite element software ANSYS, the high accuracy of the present method has been demonstrated.

关键词： rectangular plate point support line support elastic foundation displacement stress three-dimensional elasticity solution