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湖南大学学报（自然科学版） 2009年第S1期36卷 96-101页

作者： TANG Wen-wu1,2,WANG Han-qing1,2(1.School of Energy Science and Engineering,central south university,Changsha,Hunan 410083,china 2.School of Civil Engineering,Hunan university of technology,Zhuzhou,Hunan 412008,china) School of Energy Science and Engineering Central South University Changsha 410083 China School of Civil Engineering Hunan University of Technology Zhuzhou 412008 China

This paper presented an entropy evaluation method for the influences of condense heat recovery system on the *** at the damage of the condense heat to the environment,an entropy of resource loss and an emission entropy from the condense heat recovery system in the air conditioning refrigerating machine were *** the evaluation of the entropies,we developed a new algorithm for the parameter identification,called the composite influence coefficient,based on the Least Squares Support Vector Machine *** simulation,the numerical experiments shows that the Least Squares Support Vector Machine method is one of the powerful methods for the parameter identification to compute the damage entropy of the condense heat,with the largest training error being-0.025(the relative error being-3.56%),and the biggest test error being 0.015(the relative error being 2.5%).

关键词： air-conditioning refrigerating machine condense heat entropy evaluation LS-SVM

ELASTO-PLASTIC STIFFNESS MATRIX OF ROCK MASS ELEMENT WITH SOFT CLAY STRATA AND ITS APPLICATION

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中国有色金属学会会刊：英文版 1993年第2期3卷 15-17页

作者： Li,Zhenzi Sun,Zongqi central-south university of technology,Changsha,Hunan,410083,china

The fault element is used to handle soft clay strata in a rock *** formulas or clasto-plastic stiffnessmatrix for the fault element are derived using the constitutive relationship between plastic increment stress ands... 详细信息

关键词： rock mass clement fault clasto-plastic stiffness matrix

INFILTRATION MECHANISM AND QUALITY CONTROL OF CONTACT MATERIALS

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中国有色金属学会会刊：英文版 1993年第3期3卷 36-41页

作者： Wang, Fusheng Zhou, Zaiming Liang, Ronghai central-south university of technology, Changsha 410083, china

The infiltration mechanism, which has great significance for the quality control of electrieal contact material made from W-Cu, W-Ag alloys with high content of tungsten, has been studied. And a directive infiltration... 详细信息

关键词： contact material W-Cu alloy W-Ag alloy infiltration mechanism infiltrant leakage black core

MECHANISM AND APPLICATION OF COAL DRY BENEFICIATION WITH AIR-DENSE MEDIUM FLUIDIZED BED

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Journal of central south university 1998年第2期10卷 27-30页

作者： Wei Lubin (Department of Mineral Engineering, central south university of technology, Changsha 410083,china) Department of Mineral Engineering Central South University of Technology Changsha 410083 China

The mechanism of beneficiation with air dense fluidized bed has been theoretically studied in the paper. Focusing attention on the misplacing resources in separation process, the misplacing effects are divided into two parts called respectively as misplacing effect of viscosity and misplacing effect of motion. The proposed separation theory can reasonably explain the results of separation in different fluidization states. Experimental results in pilot and commercial plants showed that the air dense medium fluidized bed is a high efficiency dry cleaning technique. The dynamic stability of fluidized bed density is directly affected by the variation of fine coal content in fluidized bed and can be controlled in expected range through measurement of fluidized bed density and adjusting of split flow rate. With air dense medium fluidized bed, various coals of size 50—6 mm can be efficiently beneficiated. The separation density can be adjusted between 1.2—2.2 g/cm 3, and the probable error E p value is about 0.06.

关键词： dry beneficiation air dense medium fluidized bed separation mechanism

Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

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Science china Chemistry 2007年第6期50卷 764-769页

作者： TANG KeWen1,2, ZHANG GuoLi2, HUANG KeLong2, LI Yuanjian3 & YI JianMin1,2 1 Department of Chemistry and Chemical Engineering, Hunan Institute of Science and technology, Yueyang 414000, china 2 College of Chemistry and Chemical Engineering, central south university, Changsha 410083, china 3 College of Pharmaceutical Science, central south university, Changsha 410078, china Department of Chemistry and Chemical Engineering Hunan Institute of Science and TechnologyYueyang 414000China College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2-dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for S-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of S-CHMA in aqueous phase reached 27.6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for S-CHMA(k_S)and separation factor(alpha)are 2.44,0.89 and 2.49,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

Finite Element Analysis of Die Geometry and Process Conditions Effects on Equal Channel Angular Extrusion for β-Titanium Alloy

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Journal of Iron and Steel Research International 2012年第10期19卷 54-58页

作者： SI Jia-yong1,2, GAO Fan3, ZHANG Ji3 (1. State Key Laboratory of Powder Metallurgy, central south university, Changsha 410083, Hunan, china 2. College of Mechanical and Electrical Engineering, central south university of forestry and technology, Changsha 410004, Hunan, china 3. High Temperature Material Research Division, central Iron and Steel Research Institute, Beijing 100081, china) [a] State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 Hunan China [b] College of Mechanical and Electrical Engineering Central South University of Forestry and Technology Changsha 410004 Hunan China [c] High Temperature Material Research Division Central Iron and Steel Research Institute Beijing 100081 China

The finite element analysis was applied to evaluate the respective influences of die geometry and process conditions on plastic strain distribution for β-titanium (Ti-13V11Cr3Al) alloy during the equal channel angular extrusion (ECAE). It was found that optimum equal channel angular extrusion die geometry is strongly material dependent. Optimal strain homogeneity in the Ti-13V11Cr3Al alloy may be achieved at r (inner radius)=5 mm, R (outer radius)=3 mm. The equivalent plastic strain increases with increasing friction coefficient. And the better homogeneity of the equivalent plastic strain distribution can be achieved when friction coefficient value is lower. The faster the ram speed is, the lower the homogeneity of the equivalent plastic strain distribution is and the influence is slight. The back-pressure does not help to improve the plastic strain homogeneity, and the increasing temperature has a slightly favourable effect on the plastic strain homogeneity between 400 and 600 ℃.

关键词： equal channel angular extrusion finite element analysis die geometry β-titanium

MEASURING PRECISION OF INDUCED POLARIZATION METHOD

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中国有色金属学会会刊：英文版 1994年第4期4卷 1-6页

作者： He,Jishan(central south university of technology,Changsha 410083)

ＭＥＡＳＵＲＩＮＧＰＲＥＣＩＳＩＯＮＯＦＩＮＤＵＣＥＤＰＯＬＡＲＩＺＡＴＩＯＮＭＥＴＨＯＤ￥Ｈｅ，Ｊｉｓｈａｎ（ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ，Ｃｈａｎｇｓｈａ４１００８３）Ａｂ... 详细信息

ＭＥＡＳＵＲＩＮＧＰＲＥＣＩＳＩＯＮＯＦＩＮＤＵＣＥＤＰＯＬＡＲＩＺＡＴＩＯＮＭＥＴＨＯＤ￥Ｈｅ，Ｊｉｓｈａｎ（ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ，Ｃｈａｎｇｓｈａ４１００８３）Ａｂｓｔｒａｃｔ：Ｏｎｔｈｅｐｒｅｍｉ...

关键词： measuring precision induced polarization method (IP) dual-frequency IP frequency domain IP time IP

THE TOLERANCE DESIGN MANUFACTURE AND RELIABILITY

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中国有色金属学会会刊：英文版 1995年第2期5卷 127-130页

作者： Jiang, Jianchun(Department of Mechanical Engineering,central south university of technology, Changsha 410083) central south Univ of technology Changsha China

ＴＨＥＴＯＬＥＲＡＮＣＥＤＥＳＩＧＮＭＡＮＵＦＡＣＴＵＲＥＡＮＤＲＥＬＩＡＢＩＬＩＴＹ￥Ｊｉａｎｇ，Ｊｉａｎｃｈｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃｈａｎｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉ... 详细信息

ＴＨＥＴＯＬＥＲＡＮＣＥＤＥＳＩＧＮＭＡＮＵＦＡＣＴＵＲＥＡＮＤＲＥＬＩＡＢＩＬＩＴＹ￥Ｊｉａｎｇ，Ｊｉａｎｃｈｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃｈａｎｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏ...

关键词： tolerance fit reliability service probability distribution machining precision tribology design CAD

Fabrication and properties of binder for powder extrusion molding

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Rare Metals 2003年第2期22卷 98-102页

作者： ZHOUJicheng HUANGBaiyun SchoolofPhysicsScienceandtechnology CentralSouthUniversityChangsha410083China StateKeyLaboratoryforPowderMetallurgy CentralSouthUniversityChangsha410083China

By optimizing formulation and fabrication methods, a new binder forplasticizing powder extrusion molding of hard metal, with excellent integrated properties anduniform distribution characters, has been developed. Thermal debonding mechanism and the extrudingtheological behaviours have been studied. The technology of fabrication of binder and thermaldebonding process have also been investigated. Using the novel binder, the hard-metalextrusion-molding rods with diameter up to 25mm, have been manufactured.

关键词： powder metallurgy binder powder extrusion molding thermal debonding rheology hard metal

Effect of Trace Sc and Zr on the Mechanical Properties and Microstructure of A1 Alloy 2618

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Journal of Materials Science & technology 2000年第4期16卷 416-420页

作者： Kun YU, Songrui LI and Wenxian LI (Department of Materials Science and Engineering, central south university of technology, Changsha 410083, china) Department of Materials Science and Engineering Central South University of Technology Changsha 410083 China

An experimental 2618(Al-Cu-Mg-Fe-Ni) alloy added with trace Sc and Zr was prepared by ingot metallurgy (IM) method. The aging behavior of the alloy was studied by Vickers hardness measurement at 200℃ and 300℃. and the tensile properties of alloy specimens were measured at 20℃, 200℃, 250℃ and 300℃. The microstructure was observed by using optical microscope, SEM and TEM. It was found that the addition of Sc and Zr to 2618 alloy resulted in a primary Al_3(Sc,Zr) phase which could refine the grain because it acts as nuclei of heterogeneous crystallization in the melt during solidification. The secondary Al_3(Sc,Zr) particles were full coherent with matrix and had obvious precipitation hardening effect. They also made the S' phase precipitate more homogeneous. So the strength of alloy increases at both ambient and elevated temperatures without a decrease of ductility. The ductile fracture of alloy occurs by microvoid nucleation, growth and coalescence, so the microvoid coalescence is the dominant fracture mechanism.

关键词： Sc Zr Effect of Trace Sc and Zr on the Mechanical Properties and Microstructure of A1 Alloy 2618