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Journal of Materials Science & Technology 2001年第1期17卷 45-46页

作者： D.Y.Li and X.Ma dep.. of Chemical and Materials Engineering, university of Alberta, Edmonton, Alberta, Canada T6G 2G6 dep. of Chem. Univ. of Alberta Edmonton Canada

It has recently been found that TiNt shape memory alloy has another attractive property; high resistance to wear. The wear resistance of this alloy benefits from its pseudoelasticity (PE). It has, however, been noticed that other mechanical properties also affect the wear resistance, especially the hardness. Research was conducted to investigate the correlation between the wear resistance and both the PE and hardness. It has been demonstrated that when the PE is high, lower hardness leads to higher wear resistance.

关键词： TiNi Variations in Wear Resistance of a Novel Triboalloy Pseudoelastic TiNi Alloy-with Respect to its Pseudoelasticity and Hardness

A Multi-Interface Remote Monitoring and Control System architecture Based on Embedded Server

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Journal of Harbin Institute of Technology(New Series) 2013年第6期20卷 67-76页

作者： He Liu Lei Wang Sheng-Peng Sun Ya-Dong Wang dep. of Biomedical Engineering Harbin Institute of Technology Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences dep. of Measurement-Control Technology Harbin University of Science and Technology

This paper presents a multi-interface embedded server architecture for remote real-time monitoring system and distributed monitoring applications. In the scheme,an embedded microprocessor( LPC3250 from NXP) is chosen as the CPU of the embedded server with a linux operation system( OS) environment. The embedded server provides multiple interfaces for supporting various application scenarios. The whole network is based on local area network and adopts the Browser / Server( B / S) model. The monitoring and control node is as a browser endpoint and the remote node with an embedded server is as a server endpoint. Users can easily acquire various sensors information through writing Internet protocol address of remote node on the computer browser. Compared with client / server( C / S) mode,B / S model needs less maintain and can be applicable to large user group. In addition,a simple network management protocol( SNMP) is used for management of devices in Internet protocol( IP) networks. The results of the demonstration experiment show that the proposed system gives good support to manage the network from different user terminals and allows the users to better interact with the ambient environment.

关键词： muhi-interface remote monitoring and control embedded server simple network management protocol (SNMP)CLC number:TP216+.1 Document code:AArticle ID:1005-9113(2013)06-0067-10

A Semigroup Treatment to Viscosity Solutions of the Hanilton-Jacobi Fquation

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Chinese Quarterly Journal of Mathematics 1993年第2期8卷 94-101页

作者：宋清芳朱大新 dep. of Math. Henan University dep. of Math. Tianjin Unicersity

关键词：半群处理黏性解 Hamilton-Jacobi方程广义解 Lipschitz连续时间独立方程柯西问题半群生成元

THE PERTURBATION SOLUTIONS OF THE FLOW IN A ROTATING CURVED ANNULAR PIPE

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Journal of Hydrodynamics 2001年第1期13卷 75-80页

作者： Zhang Ben-zhao, Chen Qian, Zhang Jin-suo, Cui Liang-chen dep.rtment of Mechanics, Zhejiang university, Hangzhou, 310027, China[WT5”HZ] dep. of Mechanics Zhejiang Univ. Hangzhou 310027 China

WT5”BZ]In this paper, the flow in a rotating curved annular pipe is examined by a perturbation method. A second order perturbation solution is presented. The characteristics of the secondary flow and the axial flow are studied in detail. The study indicates that the loops of the secondary flow are more complex than those in a curved annular pipe without rotation and its numbers dep.nd on the ratio of the Coriolis force to centrifugal force F. As F≈-1, the secondary flow has eight loops and its intensity reaches the minimum value, and the distribution of the axial flow is like that of the Poiseuille flow. The position of the maximum axial velocity is pushed to either outer bend or inner bend, which is also determined by F. [WT5”HZ]

关键词： rotating curved annular pipe secondary flow Coriolis force centrifugal force perturbation solution

CHANGES OF MEAN VELOCITY PROFILES IN THE WAVE-CURRENT COMBINED FLOW

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Journal of Hydrodynamics 2001年第1期13卷 47-53页

作者： Wu, Y.S. Lian, J.J. Zhang, Q.H. Qin, C.R. dep. of Hydraulic Eng. Tsinghua Univ. Beijing 100084 China

A mathematical model is developed to simulate the change in mean velocity for the coexistent case of waves and current. The experimental results of mean velocity profile in a wave-current flume show the following features: Eulerian mean current profile for following current is more uniformly distributed than the corresponding pure current case, whereas , the case of an opposing current leads to the more straight profile. This model is based on Eulerian mean framework, and motions of wave and current are solved simultaneously. The comparisons of numerical results and experimental data show that the mathematical model presented in this paper is reasonable and feasible.

关键词： Computer simulation Hydrodynamics Mathematical models Sediment transport

Mechanical parameter evolutions and deterioration constitutive model for ductile-brittle failure of surrounding rock in high-stress underground engineering

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Underground Space 2024年第2期15卷 131-152页

作者： Zhi Zheng Ronghua Li Qiang Zhang Xiaohua Huang Wei Wang Shuling Huang State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang 110819China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources Yangtze River Scientific Research InstituteWuhan 430010China

The deep surrounding rock is usually in the true triaxial stress state,and previous constitutive models based on the understanding of uniaxial and conventional triaxial test results have difficulty characterizing the degradation and fracture process of rock ductile–brittle failure under true triaxial stress ***,this study conducted a series of true triaxial tests to obtain the understanding of the ductile–brittle behaviour of rock,and then combined the test results and the Mogi–Coulomb strength criterion,and proposed calculation methods for the elastic modulus E,cohesion c and internal friction angle u and the evolution functions of E,c and u of rock under true triaxial *** the decreasing of the minimum principal stress r3 or increasing of the intermediate principal stress r2,the marble post-peak stress drop rate gradually increases,the ductility gradually weakens,and the brittleness significantly *** calculation method and evolution function of rock E,c and u under true triaxial stress were proposed.E decreased at first and then tended to remain stable with the increasing of equivalent plastic strain increment dep.c and u slowly increased at first and then rapidly *** a method of parameter degradation rate to realize post-peak stress drop rate to reflect the ductile–brittle characteristics,a new three-dimensional ductile–brittle deterioration mechanical model(3DBDM)was *** proposed model can accurately characterize the influence of r2 and r3 on mechanical parameters,the ductile–brittle behaviour of rock under true triaxial stresses,and the asymmetric failure characteristics of surrounding rock after excavation of deep underground *** proposed model can be reduced to elastic–perfectly plastic,elastic–brittle,cohesion weakening friction strengthening(CWFS),Mohr–Coulomb,and Drucker–Prager models.

关键词： True triaxial stress Post-peak characteristics 3D deterioration model Elastic modulus evolution Cohesion and friction angle evolution

A Study on the Kinetics of the Catalytic Reforming Reaction of CH4 with CO2: Determination of the Reaction Order

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Journal of Natural Gas Chemistry 2003年第3期12卷 201-204页

作者： Chunyang Ji, Lihong Gong, Jiawei Zhang, Keying ShiChemistry dep.rtment of Harbin Normal university, Harbin 150080, China Chem. dep. Harbin Normal university Harbin 150080 China

The kinetics of the catalytic reforming reaction of methane with carbondioxide to produce synthesis gas on a Ni/α-Al_2O_3 and a HSD-2 type commercial catalyst has beenstudied. The results indicate that the reaction orders are one and zero for methane and carbondioxide, respectively, when the carbon dioxide partial pressure was about 12.5-30.0 kPa and thetemperature was at 1123-1173 K. However, when the carbon dioxide partial pressure was changed to30.0-45.0 kPa under the same temperature range of 1123-1173 K, the reaction orders of methane andcarbon dioxide are one. Furthermore, average rate constants at different temperatures weredetermined.

关键词： reforming methane carbon dioxide reaction order rate constant kinetics

Fatigue Behavior of Cemented Carbide Die in Cold Forging of Steel

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Journal of Materials Science & Technology 2001年第1期17卷 51-52页

作者： Z.Wang and K.Dohda dep.. of Mechanical System Engineering, Gifu university, Gifu, Japan dep. of Mech. Syst. Eng. Gifu Univ. Gifu Japan

The fatigue behavior of cemented carbide die under service load in the multistage cold forging of steel was investigated. It was found that the fatigue cracks do not initiate at the stress concentration position and the crack initiation position can be classified to three types. The crack initiation position can be predicted by FEM only when the plastic deformation of the die is considered.

关键词： Fatigue Behavior of Cemented Carbide Die in Cold Forging of Steel

Mechanism of the Forming of Nodular Graphite

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Journal of Materials Science & Technology 2000年第6期16卷 615-618页

作者： Shoukui ZHANG (dep.. of Materials Engineering, Dalian university of Technology, Dalian 116024, China) [Manuscript received September 6, 1999, in revised form January 21, 2000] dep. of Materials Eng. Dalian Univ. of Technol. Dalian 116024 China

This article presents a theory about the growth mechanism of bubble-screw dislocation of nodular graphite. Normally speaking, the crystallizing procedure of most nodular graphite is as follows: firstly, graphite generates nuclei on bubbles and fills them (mainly in the way of screw dislocation) forming the complete nuclei of nodular graphite-graphite bubble nuclei. Then, graphite grows up in the way of screw dislocation. Two important conditions concerning the production of nodular graphite are: (a) there is a relatively big interfacial energy between ferro liquid and graphite, and the one between ferro liquid and graphite prismatic plane is bigger than that between ferro liquid and graphite basal plane; (b) there are a certain amount of micro-bubbles in the melt.

关键词： Mechanism of the Forming of Nodular Graphite

Mathematical Modeling of Metal Active Gas (MAG) Arc Welding

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Journal of Materials Science & Technology 2001年第1期17卷 167-168页

作者： Takayoshi Ohji Yoko Tsuji Fumikazu Miyasakn and Takeshi Yamamoto dep.rtment of Adaptive Machine Systems, Osaka university 2-l, Yamada-oka, Suita, Osaka, 565-0871, Japan dep. of Adaptive Machine Syst. Osaka Univ. Osaka 565-0871 Japan

In the present paper. a numerical model for MAG (metal active gas) arc welding of thin plate has been developed. In MAG arc welding, the electrode wire is melted and supplied into the molten pool intermittently. Accordingly, it is assumed on the modeling that the thermal energy enters the base-plates through two following mechanisms, i.e., direct heating from arc plasma and 'indirect' heating from the dep.sited metal. In the second part of the paper, MAG arc welding process is numerically-analyzed by using the model. and the calculated weld bead dimension and surface profile have been compared with the experimental MAG welds on steel plate. As the result. it is made clear that the model is capable of predicting the bead profile of thin-plate MAG arc welding, including weld bead with undercutting.

关键词： POOL