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Effect of Tin on the Reaction Synthesis of Ternary Carbide Ti_3AlC_2

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Journal of wuhan university of {2.(Materials science) 2009年第2期24卷 283-286页

作者：周卫兵 School of Materials science and engineering Wuhan University of Technology

The effect of tin on synthesis of Ti3AlC2.by spark plasma sintering （SPS） from TiC/Ti/Al powders was investigated. X-ray diffraction （XRD） and scanning electron microscopy （SEM） were used for phase identification and microstructure evaluation. The experimental results show that addition of tin can considerably accelerate the synthesis reaction of Ti3AlC2.and fully dense, essentially single-phase polycrystalline Ti3AlC2.could be successfully obtained by sintering 2.iC/1Ti/1Al/0.2.n powders at 12.0-12.0 ℃ under a pressure of 30 MPa. SEM images show that Ti3AlC2.samples in about 2.5 μm thick and 10-2.μm long platelets can be obtained. The fracture toughness and flexural strength of Ti3AlC2.were 6.5±0.2.MPa·m^1/2.and 560±10 MPa, respectively.

关键词： titanium aluminum carbide spark sintering technique synthesis

GEAR CRACK EARLY DIAGNOSIS USING BISPECTRUM DIAGONAL SLICE

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Chinese Journal of Mechanical engineering 2003年第2期16卷 193-196页

作者： Li WeihuaZhang GuicaiShi TielinYang ShuziSchool of Mechanical scienceand engineering,{2. university of scienceand technology,wuhan 43.074, china School of Mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074

A study of bispectral analysis in gearbox condition monitoring is *** theory of bispectrum and quadratic phase coupling (QPC) is first introduced, and then equationsfor computing bispectrum slices are obtained. To meet the needs of online monitoring, a simplifiedmethod of computing bispectrum diagonal slice is adopted. Industrial gearbox vibration signalsmeasured from normal and tooth cracked conditions are analyzed using the above method. Experimentsresults indicate that bispectrum can effectively suppress the additive Gaussian noise andchracterize the QPC phenomenon. It is also shown that the 1-D bispectrum diagonal slice can capturethe non-Gaussian and nonlinear feature of gearbox vibration when crack occurred, hence, this methodcan be employed to gearbox real time monitoring and early diagnosis.

关键词： condition monitoring gear crack early diagnosis quadratic phase coupling bispectrum diagonal slice

Experimental study on high viscosity fluid micro-droplet jetting system

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science china(Technological sciences) 2010年第1期53卷 182-187页

作者： SHU XiaYun1,2.ZHANG HongHai1,2.LIU HuaYong1,2.XIE Dan1,2.& XIAO JunFeng1,2.1 School of Mechanical science and engineering,{2. university of science and technology,wuhan 43.074,china 2.Division of MOEMS,wuhan National Laboratory of Optoelectronics,wuhan 43.074,china 1. School of Mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074 China2. Division of MOEMS Wuhan National Laboratory of Optoelectronics Wuhan 430074 China

Fluid dispensing is a method by which fluid materials(such as epoxy,adhesive,and encapsulant) are delivered in a controlled manner in electronics *** jetting,derived from inkjet technology,is a noncontact,data-driven fluid dispensing *** ideal fluid materials for packaging are usually high viscous,which is difficult to realize by traditional inkjet *** this paper,a mechanical micro-droplet jetting system for high viscosity fluid was *** consists of dispensing valve,motion stage,temperature control subsystem,pneumatic subsystem,driving circuit for solenoid valve,and system control *** of this system under various circumstances was studied by changing several parameters,including working temperature,stroke length,back pressure and drive pulse *** droplets of 0.35 mm in diameter were produced by stainless steel nozzle of 0.2.mm in diameter in the experimental study.

关键词： high viscosity fluid micro-jetting microelectronics packaging

Influence of Calcium Sulfate State and Fineness of Cement on Hydration of Portland Cements Using Electrical Measurement

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Journal of wuhan university of {2.(Materials science) 2006年第4期21卷 141-145页

作者：魏小胜 Department of Civil engineering Huazhong University of Science and Technology Wuhan 430074 China

The influence of calcium sulfate state and fineness of cement on hydration of Portland cement was studied using electrical resistivity measurement. The bulk resistivity curve of the paste from the abnormal cement mainly with hemihydrate had a characteristic abnormal peak and rapid increase in early period. The resistivity measurement technique can be used to discriminate abnormal setting. For normal cement with gypsum, the increase in fineness of the Portland cement decreases the minimum resistivhy due to a higher ionic concentration and increases the 2. hour resistivity due to a reduction in macroscopic pore size. The setting time, compressive strength, pore structure of pastes made from different cements were carried out to compare the influence of water to cement ratio, calcium sulfate state and fineness. It is found that the electrical and mechanical properties are strongly affected by the initial porosity, the presence of hemihydrate or gypsum, and the fineness of cement.

关键词： false setting electrical resistivity fineness hydration

Flexural-tensile Properties of Layered Steel Fiber Reinforced Rubber Concrete

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Journal of wuhan university of {2.(Materials science) 2009年第5期24卷 846-848页

作者：易贤仁 School of sciences Wuhan University of Technology

Layered steel fiber reinforced rubber concrete （LSFRRC）, a new type of pavement concrete based on the requirements of national standard were experimentally researched. The different properties of flexural-tensile strength from plain concrete （PC）, rubber concrete （RC）, layered steel fiber reinforced concrete （LSFRC） and LSFRRC were presented. Experimental results show that the tensile strength of LSFRRC is improved by 4.12. compared with PC, by 13.75% compared with RC. The load-deflection curve on flexural-tensile propertiesis put forward. The flexural-tensile toughness index I10 of LSFRRC is improved 10.32.times compared with PC.

关键词： RC LSFRRC flexural-tensile strength load-deflection curve experimental re-search

Chitosan——L-Lactic Acid Scaffold for the Regeneration of Peripheral Nerve and Its NGF Release Properties

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Journal of wuhan university of {2.(Materials science) 2009年第6期24卷 961-964页

作者：徐海星 Department of Pharmaceutical engineering School of Chemical EngineeringWuhan University of Technology

Chitosan—L-lactic acid composite scaffold for the regeneration of peripheral nerve is obtained by grafting L-lactic acid onto the amino groups in chitosan with combined vacuum freezer drier. The composite scaffold was characterized by ATR-FTIR and SEM. The scaffold has a better graft efficiency and has a dense inner layer and a loose outer layer with porous structure, and the pore size is about 100 μ*** NGF release properties of the scaffold were investigated. The experimental results showed that, at the 1st day, 15.2.ng of NGF on average was released from the scaffold. From day 2.to day 10, the release rate obviously slowed down and 1.64 ng of NGF was released on average every day. After 10 days, the release rate was slower and 10.3 ng of NGF was released on average every day. After 60 days, NGF could also maintained a certain concentration. These properties show that the scaffold is a better carrier for NGF which can be more advantageous to the regeneration of the damaged peripheral nerve. As a result, this composite scaffold would be an ideal candidate for the regeneration of damaged peripheral nerve.

关键词： chitosan L-lactic acid peripheral nerve NGF release properties

Application of the annexation principle to the study of thermodynamic properties of ternary metallic melts In-Pb-Ag and In-Bi-Sb

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Rare Metals 2002年第2期21卷 142-151页

作者： ZHANG JianMetallurgical engineering school.university of {2. and technology Beijing, Beijing 100083, china Metallurgical engineering School University of Science and Technology Beijing 北京 100083

Based on the phase diagrams, measured activities an the annexationprinciple, the calculating models of mass action concentrations forin-Pb-Ag and In-Bi-Sb ternary metallic melts have been *** results of calculation both agree with practice, and obey the lawof mass action, showing that the models formulated can reflect thestructural reality of the corresponding melts and the annexationprinciple is applicable to the them.

关键词： activity mass action concnetration th annexation principle In-PB-Ag

Fuzzy MCDM Based on Fuzzy Relational Degree Analysis

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Journal of Systems engineering and Electronics 2002年第1期13卷 1-7页

作者： Song Yexin Dept. of Basic Courses, Naval university of engineering, {2. 430033,P.R.china Chen Mianyun Dept. of Control science and engineering, huazhong university of science and technology, wuhan 43.074,P.R.china Dept. of Basic Courses Naval University of Engineering Wuhan 430033 P. R. China Dept. of Control science and engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China

This paper presents a new fuzzy multiple criteria (both qualitative and quantitative) decision-making (MCDM) method based on fuzzy relational degree analysis. The concepts of fuzzy set theory are used to construct a weighted suitability decision matrix to evaluate the weighted suitability of different alternatives versus various criteria. The positive ideal solution and negative ideal solution are then obtained by using a method of ranking fuzzy numbers, and the fuzzy relational degrees of different alternative versus positive ideal solution and negative ideal solution are calculated by using the proposed arithmetic. Finally, the relative relational degrees of various alternatives versus positive ideal solution are ranked to determine the best alternative. A numerical example is provided to illustrate the proposed method.

关键词： Fuzzy sets Management science Matrix algebra Systems engineering

On Incentive Strategy with a kind of Incomplete Information

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Systems science and Systems engineering 1994年第2期4卷 119-124页

作者： JIN Wu CHEN Ting(institute of Systems engineering,{2.,wuhan, 43.074, china)

The designing of incentive strategy when the follower’s objective functions have Parameters unknown to the leader is investigated in this paper. A desinging approach named IncentiveStrategy with Unknown but Bounded ... 详细信息

关键词： Sthekelberg game incentive strategy incomplete information unknown but bounded error.