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DYNAMIC RESPONSE OF SHAPE MEMORY ALLOY SYSTEM AND ITS VIBRATION CONTROL

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Chinese Journal of Mechanical engineering 2000年第4期13卷 312-317页

作者： Wei ZhiSun Dongchang Tan Runhua (school of Mechanical engineering,Hebei university of Technology) 河北工业大学天津

A hysteric model is represented to describe the dependence of restoring force on deformation of pseudoelastic *** dynamic response of the system is investigated by means of mathematical *** result shows that this kind of vibration absorbing system can suppress vibration with large amplitude ***,the vibration absorbing system can work in optimum state by adjusting temperature and using piezoelectric sensors and actuators.

关键词： Shape memory alloy Pseudoelasticity Mathematical model Dynamic response Vibration control

A New Safety Electric Initiating System

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 306-308页

作者： Daze Lin(Resource engineering school, university of Science and Technology Beijing, Beijing 100083, China) Univ of Science and Technology Beijing Beijing China

Based on the analysis of weakness on the safety of traditional electric detonators, a BJ-l safety electric detonator initiatingsystem and its corresponding safe examination technique were successfully developed. By leading false foot wires and taking advantageof the transmitting frequency band of Mo-Zn ferrite, detonators in this new system can completely impede the direct induction of outsidecrosstalk that may cause casual firing in the ordinary as well as eleclromagnetic ones. Possible causality by lightning was discussed. Results are presented, of its safety tests on resistance to direct and alternating current, electrostatic, and crosstalk induced by damp leakagein saturated salty water.

关键词： electric detonator blasting engineering, electric initiating system, safety

Producing Calcium-Bearing Mullite Thermal-Insulating Refractories by Kyanite

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 50-53页

作者： Wen Ni (Resources engineering school, university of Science and Technology Beijing, Beijing 100083, China) Resources engineering school University of Science and Technology Beijing Beijing 100083 China

To improve the physical properties, a series of experiments have been camed out to produce calcium-bearing mullite thermal-insulating refractories by using kyanite as major raw materials. The experiments were carried out by a foaming technique and using white cement as a combing agent. The results show that the calcium-bearing mullite refractory has much better physical properhes than traditional clay refractory and high-alumina refractory.

关键词： mullite thermal-insulating refractory kyanite

AN INVESTIGATION ON COMPUTER-CONTROLLED TURNING AND CONTOUR DESIGNING OF SHAPED CONNECTION

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Chinese Journal of Mechanical engineering 2000年第4期13卷 278-284页

作者： He XiaojiaDing Chongsheng He Yue (school of Mechanical engineering, Xi’an Jiaotong university) 西安交通大学陕西西安

The computer-controlled turning technique of shaped connection (keyless connection), shaft and hole, is discussed. By using the method, a clearance free fit with a taper is obtained. After the comparison of the mechanical behavior and the turning machinability of the contours, it is found that the present contour needs further improvement, and a new contour is presented.

关键词： Shaped connection Profiling turning Computer-controlled machining

Theoretical study of bifurcated bent blue-shifted hydrogen bonds CH_2…Y

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Science China Chemistry 2008年第7期51卷 623-631页

作者： LI AnYong school of Chemistry and Chemical engineering, Southwest university, Chongqing 400715, China school of Chemistry and Chemical engineering Southwest University Chongqing China

Ab initio quantum chemistry methods were applied to study the bifurcated bent hydrogen bonds Y… H2CZ (Z = O, S, Se) and Y…H2CZ2 (Z = F, Cl, Br) (Y = Cl-, Br-) at the MP2/6-311++G(d,p) and MP2/6-311++G(2df,2p) levels. The results show that in each complex there are two equivalent blue-shifted H-bonds Y…H—C, and that the interaction energies and blue shifts are large, the energy of each Y…H—C H-bond is 15-27 kJ/mol, and Δr(CH) = -0.1 - -0.5 pm and Δv(CH) = 30 - 80 cm-1. The natural bond orbital analysis shows that these blue-shifted H-bonds are caused by three factors: large rehybridization; small direct intermolecular hyperconjugation and larger indirect intermolecular hy- perconjugation; large decrease of intramolecular hyperconjugation. The topological analysis of elec- tron density shows that in each complex there are three intermolecular critical points: there is one bond critical point between the acceptor atom Y and each hydrogen, and there is a ring critical point inside the tetragon YHCH, so these interactions are exactly H-bonding.

关键词： bifurcated bent H-bonds blue-shifted H-bonds topological property of electron density intramolecular hyperconjugation

Corrosion science general-purpose data model and interface (Ⅱ): OOD design and corrosion data markup language (CDML)

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Science China(Technological Sciences) 2008年第11期51卷 1850-1857页

作者： TANG ZiLong school of Materials Science and engineering, Tianjin university, Tianjin 300072, China school of Materials Science and engineering Tianjin University Tianjin China

With object oriented design/analysis, a general purpose corrosion data model (GPCDM) and a corrosion data markup language (CDML) are created to meet the increasing demand of multi-source corrosion data integration and sharing. "Cor- rosion data island" is proposed to model the corrosion data of comprehensiveness and self-contained. The island of tree-liked structure contains six first-level child nodes to characterize every important aspect of the corrosion data. Each first-level node holds more child nodes recursively as data containers. The design of data structure inside the island is intended to decrease the learning curve and break the acceptance barrier of GPCDM and CDML. A detailed explanation about the role and meaning of the first-level nodes are presented with examples chosen carefully in order to review the design goals and requirements proposed in the previous paper. Then, CDML tag structure and CDML application programming interface (API) are introduced in logic order. At the end, the roles of GPCDM, CDML and its API in the multi-source corrosion data integration and information sharing are highlighted and projected.

关键词： corrosion data model corrosion data markup language (CDML) application programming interface (API) information sharing

Identifying rock blocks based on hierarchical rock-mass structure model

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Science China Earth Sciences 2009年第10期52卷 1612-1623页

作者： XU NengXiong school of engineering and Technology, China university of Geosciences, Beijing 100083, China school of engineering and Technology China University of Geosciences Beijing China

Rock-masses are divided into many closed blocks by deterministic and stochastic discontinuities and engineering interfaces in complex rock-mass engineering. Determining the sizes, shapes, and adjacent relations of blocks is important for stability analysis of fractured rock masses. Here we propose an algorithm for identifying spatial blocks based on a hierarchical 3D Rock-mass Structure Model (RSM). First, a model is built composed of deterministic discontinuities, engineering interfaces, and the earth's surface, and the deterministic blocks surrounded by these interfaces are traced. Then, in each deter-ministic block, a network model of stochastic discontinuities is built and the stochastic blocks are traced. Building a unitary wire frame that connects all interfaces seamlessly is the key for our algorithm to identify the above two kinds of blocks. Using this algorithm, geometric models can be built for block theory, discrete element method, and discontinuous deformation analysis.

关键词： rock-mass engineering discontinuity block identification 3D Rock-mass Structure Model network model of stochastic discontinuities

Corrosion science general-purpose data model and interface (Ⅲ):Data integration and management environment

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Science China(Technological Sciences) 2008年第12期51卷 2089-2094页

作者： TANG ZiLong school of Materials Science and engineering,Tianjin university,Tianjin 300072,China school of Materials Science and engineering Tianjin University Tianjin China

A brand new Corrosion Data Integration and Management Environment(CDIME) is developed in Java programming language based on general-purpose corrosion data model(GPCDM) and corrosion data markup language(CDML) proposed in the previous *** general,the functionalities and features of CDIME meet most of design requirements including composition,inheritance,self-contained,relatively independence and so *** insight tutorial is introduced on the life circle of corrosion data islands from its creation,maintenance,and application like *** template feature makes the building of comprehensive data island as simple as a few mouse ***-only publishing of data as e-Book and PDF hold their own *** document can be imported and exported freely on any running *** achieving feature is addressed in detail because it is critical to data sharing and integration in *** the end,a real example is presented to help the understanding of data islands assembling and the advanced features offered by CDIME.

关键词： corrosion software data model information integration

TiC/Fe cermet coating by plasma cladding using asphalt as a carbonaceous precursor

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Progress in Natural Science:Materials International 2008年第4期18卷 447-454页

作者： Junbo Liu school of Mechanical and Electronic engineering, Weifang university, Weifang 261061, China school of Mechanical and Electronic engineering Weifang University Weifang 261061 China

A new Ti-Fe-C compound powder for plasma cladding was prepared by heating a mixture powder of ferrotitanium and asphalt pyro-lyzed as a carbonaceous precursor. The carbon by the pyrolysis of the asphalt acts as a reactive constituent as well as a binder in the compound powder. The TiC/Fe cermet coatings were prepared by plasma cladding with the compound powder. Results show that the Ti-Fe-C compound powder has a very tight structure, which can avoid the problem of the reactive constituent particles being sep- arated during cladding. The TiC/Fe cermet coating presents a typical morphology of plasma cladding coatings with two different lam- inated layers:one is the composite layer in which the round fine TiC particles (<500 nm) are dispersed within a Fe matrix, the other is the paragentic layer of TiC and Ti2O3. The coating shows high hardness and excellent wear resistance. The surface hardness of the coating is 68 ± 5(HR30N). In the same fretting conditions, the wear area of Ni60 coating is about 11 times as much as the TiC/Fe cermet coating.

关键词： Plasma cladding TiC/Fe cermet coating Precursor Microstructure Wear resistance