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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 {2.,central south university,changsha,Hunan 410083.china 2.school of Civil {2.,Hunan university of Technology,Zhuzhou,Hunan 412.08,china) school of Energy science and {2. 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-0.02.(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

Effect of Nd_2.e_(14)B/α-Fe Nanocomposite Permanent Magnets with a Combined Co and Nb Additions

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Journal of Wuhan university of Technology(materials {2.) 2009年第5期24卷 725-727页

作者：马瑞 school of materials {2. and Metallurgy engineering Guizhou University

Influence of Co＋Nb on the Nd8Fe82.o3Nb1B6 nanocomposite magnets was investigated by adding Co element combined with Nb element. Results show that the high temperature stability of two phases is increased. Adding Co＋Nb could improve the glass forming ability of the alloy, reduce the size of grains, increase the exchange coupling ability of two phases, and obviously increase the magnetic properties of the alloy. The optimal magnetic properties are Br=1.14 T, Hcj=32. kA/m, （BH）max=109.3 kJ/m^3

关键词： nanocomposite permanent magnets glass forming ability exchange coupling ability magnetic properties

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 2.mm, have been manufactured.

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

First-principles study on the lattice stability of elemental Co,Rh,and Ir in the ⅧB group

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Rare Metals 2009年第3期28卷 212-220页

作者： TAO Huijina YIN Jian YIN Zhimin ZHANG Chuangfu LI Jie HUANG Boyun school of materials {2. and engineering Central South University Changsha 410083 China school of Metallurgical science and {2. Central South University Changsha 410083 China Key Lab of Nonferrous materials science and {2. Ministry of Education of China Central South University Changsha 410083 China

Lattice constants, total energies, and densities of state of transition metals Co, Rh, and Ir in the VⅢB group with different crystalline structures were calculated via generalized gradient approximation （GGA） of the total energy plane wave pseudopotential method in first-principles. The lattice stabilities of Rh and Ir are ΔG^ bcc-hcp 〉 Δ G^fcc-hcp 〉 0, agreeing well with those of the projector augmented wave method in first-principles and the CALPHAD method in spite of elemental Co. Analyses of the electronic structures to lattice stability show that crystalline Rh and Ir with fcc structures have the obvious characteristic of a stable phase, agreeing with the results of total energy calculations. Analyses of atomic populations show that the transition rate of electrons from the s state to the p or d state for hcp, fcc, and bcc crystals of Co and Rh increases with the elemental period number to form a stronger cohesion, a higher cohesive energy, or a more stable lattice between atoms in heavier metals.

关键词： Co Rh Ir lattice stability plane wave pseudopotential method generalized gradient approximation

Preparation and characterization of nitrogen-doped titanium dioxides

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science china Chemistry 2007年第2期50卷 212-216页

作者： ZHU GuoPing1 & ZHOU KangGen2.1 Environmental science Research & Design Institute of Zhejiang Province,Hangzhou 310007,china 2.Department of Environmental {2.,school of Metallurgical science and {2.,central south university,changsha 410083.china 1. Environmental science Research & Design Institute of Zhejiang Province Hangzhou 310007 China 2. Department of Environmental engineering School of Metallurgical Science and Engineering Central South University Changsha 410083 China

A type of high visible-light active titanium oxinitride(TiO2.xNx) powder was prepared by a simple proc-ess:the calcination of the hydrated titanium dioxide at the atmosphere of ammonia-argon using a tu-bular electric furnace at high temperatures. The hydrated titanium dioxide was synthesized as the precursor of TiO2.xNx using titanic acid as raw material,which came from sulfate technique of produc-ing titanium white. The effects of temperature and reaction time on the nitrogen content,grain size and crystal structure were studied. The visible-light activity and photocatalysis capability of the powder were also investigated.

关键词： nitrogen-doped titanium dioxides visible-light activity photocatalysis titanium oxinitride

Thermal Comfort in Waiting Room at Railway Station in Cold Region in china

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湖南大学学报（自然科学版） 2009年第S1期36卷 66-70页

作者： MA Wei-wu,CHEN Qian-zhou,ZHOU Jie-min,SHI Xiang-nan,LI Li-qing,WANG Chao,CHEN Zhi-ya(1.school of Energy science and {2.,central south university,changsha,Hunan 410083.china 2.Department of Mechanical {2.,Purdue university,Calumet,Hammond 4632.,USA 3.school of Traffic and Transportation {2.,central south university,changsha,Hunan 410083.china) school of Energy science and {2. Central South University Changsha 410083 China Department of Mechanical engineering Purdue University Calumet Hammond 46323 United States school of Traffic and Transportation engineering Central South University Changsha 410083 China

A field study and analysis about the thermal comfort was carried out in the waiting room at Beijing West Rail Station in Chinese cold ***' TSV(thermal sense vote)was obtained using statistical method on the basis of more than 1 2.0 *** linear regression between TSV and indoor temperature indicates that thermal neutral temperature is 2..2.℃.According to the percentage of satisfaction among all passengers under different indoor temperatures,the acceptable temperature range in the waiting room is 2..2.30.2..It is also found that passengers' temporary stay should be taken into consideration for the thermal comfort ***' TSV is not a constant value after they enter the waiting *** fact,ΔTSV increases as passengers are waiting for the train,and the growing rate is dependent on indoor-outdoor temperature *** greater the temperature difference,the faster ΔTSV *** last,a linear regression between indoor comfortable temperature and outdoor temperature was generated as the adaptive comfort model.

关键词： waiting room thermal comfort adaptive comfort model

Preparation and characterization of molybdenum powders with copper coating by the electroless plating technique

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Rare Metals 2008年第4期27卷 434-438页

作者： WANG Guangjun WANG Dezhi school of materials {2. and engineering Central South University Changsha 410083 China

Molybdenum powders with a diameter of approximately 3 μn were coated with copper using the electroless plating technique in the pH 12.5-13 and temperature range of 55-75℃. The optimization of the electroless copper bath was evaluated through the combination of process parameters like pH and temperature. The optimized values ofpH and temperature were found to be 12.5 and 60℃, respectively, which attributes to the bright maroon color of the coating with an increase in weight of 46%. The uncoated and coated powders were subjected to microstructural studies using scanning electron microscope （SEM） and the phases were analyzed using X-my diffrction （XRD）. An attempt was made to understand the growth mechanism of the coating. The diffusion-shrinkage autocatalytic model was suggested for copper growth on the molybdenum surface.

关键词： copper coatings electroless plating copper molybdenum powders composite materials growth model

THE EFFECTS OF TRACE Ti ON THE DAMPING CAPACITY OF THE Zn-2.% Al ALLOY

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Journal of central south university 1994年第1期6卷 40-44页

作者： Zhou Shanchu Luo Binghui(Department of material science and {2., central south university of Thechnology, changsha, 410083. china) 1. Department of material science and {2. Central South University of Thechnology 410083 Changsha China

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关键词： Zn-Al alloy internal friction titanium damping stability

Electrochemical Characterization of Surface-modified LiMn_2._4 Cathode materials for Li-ion Batteries

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Journal of Wuhan university of Technology(materials {2.) 2006年第4期21卷 56-59页

作者：禹筱元 College of science South China Agricultural University Guangzhou 510642ChinaSchool of Physics & Engineering Sun Yat-sen University Guangzhou 510275China

To improve the performance, the surface of 12.n2.4 was coated with very fine MgO , Al2.3 and ZnO by solgel method, respectively. The structure and morphology of the coated materials were investigated by X-ray diffraction （ XRD ）, X-ray photoelectron spectroscopy （ XPS ） and scanning electron microscopy （SEM）. The charge and discharge performance of uncoated and surfnce modified 12.n2.4 spinel at 2.℃ and 55 ℃ were tested, using a voltage window of 3.0-4.35 V and a current deasity of 0. 1 C rate. There is a slight decrease in the initial discharge capacity relative to that of uncoated UMn2.O4, bat the cycle ability of 12.12.n2.4 coated by metal-oxide has remarkably been improved. The EIS measuremeuts of uncoated and Al2.3 -coated 12.n2.4 were carried out by a model 2.3 A potentiostatl galvanistat controUed by a computer using M2.0 software, and using a freqnency response analyzer （ Zsimpwin ） combined with a potentiostate （ PAR 2.3）. Coaseqnently, the reason for the improved cycle properties is that the surface modification reduces the dissolution of Mn , which results from the suppression of the electrolyte decomposition, and suppresses the formation of passivation film that acts as an electronic insulating layer. In conclusion, the use of surface modification is an effective way to improve the electrochemical performance of 12.n2.4 cathode material for lithium batteries.

关键词： lithium-ion batteries surface modification metal-oxide coating: 12.n2.4 cathode

Synthesis and sintering of beryllium oxide nanoparticles

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Progress in Natural science:materials International 2010年第1期20卷 81-86页

作者： Xiao-feng WANG,Ri-chu WANG,Chao-qun PENG,Ting-ting LI,Bing LIU school of materials {2. and engineering,central south university,changsha 410083.china school of materials {2. and engineering Central South University Changsha 410083 China

BeO nanoparticles were prepared by polyacrylamide gel route and the sintering properties of synthesized powder as a function of sintering temperature and time were *** behaviors of the polyacrylamide gel and beryllium salt were studied by thermogravimetry analysis(TGA).The calcination temperature(690℃)of the beryllium sulfate covered in polyacrylamide xerogel was almost 150℃lower than that obtained by traditional *** nanocrystallites of the BeO particles were estimated by X-ray diffraction(XRD)according to Debye-Scherrer *** electron microscopy(TEM) investigation revealed that the average particle size of the BeO nanoparticles prepared by calcining at 800℃for 2.h,ranges from 15 nm to 2. *** sintering temperature was down to 1600℃,which was around 2.0℃lower than conventional sintering temperature of the compact sample with common *** densification rate was fast at the first 3 *** thermal conductivity of the sample sintered at 1600℃for 6 h was 186.6 W/(m·K).

关键词： BeO nanoparticles polyacrylamide gel sintering thermal conductivity