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Characteristic atom arranging crystallogphy of alloy phases for Au-Cu system

science china(Technological sciences) 2011年第6期54卷 1560-1567页

作者： XIE YouQing1,2,3.LIU XinBi1,2,3.PENG HongJian4,NIE YaoZhuang5,LI XiaoBo6 & LI YanFen1,2,3.1 school of Materials science and engineering,{3. south university,changsha 410083.china 2 Powder Metallurgy Research Institute,{3. south university,changsha 410083.china 3.State Key Laboratory of Powder Metallurgy,{3. south university,changsha 410083.china 4 school of Chemistry and Chemical engineering,{3. south university,changsha 410083.china 5 school of Physical science and Technique,{3. south university,changsha,410083.china 6 College of Mechanical engineering,Xiangtan university,Xiangtan 411105,china school of Materials science and engineering Central South University Changsha China Powder Metallurgy Research Institute Central South University Changsha China State Key Laboratory of Powder Metallurgy Central South University Changsha China school of Chemistry and Chemical engineering Central South University Changsha China school of Physical science and Technique Central South University Changsha China College of Mechanical engineering Xiangtan University Xiangtan China

In this paper,it is pointed out that the descriptions of alloy phase structures are dependent on structural unit *** the systematic science of alloys(SSA),the alloy phase structures are described by means of the symmetry element sequence combining with characteristic atom *** is named the characteristic atom arranging structure,which can display the characteristic atoms at the lattice sites and the micro-inhomogeneity,besides the *** characteristic atom has its own characters:neighboring configuration,potential energy,volume and electronic *** micro-inhomogeneity of alloy phases can be described by concentrations and short-range ordered parameters of characteristic *** differences between the electronic structures of alloy phases and electronic structures of characteristic atoms in the alloy phases are also discussed.

关键词： systematic science of alloys Au-Cu system alloy phase structure micro-inhomogeneity

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Relaxed resource advance reservation policy in grid computing

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The Journal of china Universities of Posts and Telecommunications 2009年第2期16卷 108-113页

作者： XIAO Peng HU Zhi-gang school of Information science and engineering,{3. south university,changsha 410083.china school of Information science and engineering Central South University Changsha 410083 China

The advance reservation technique has been widely applied in many grid systems to provide end-to-end quality of service （QoS）. However, it will result in low resource utilization rate and high rejection rate when the reservation rate is high. To mitigate these negative effects brought about by advance reservation, a relaxed advance reservation policy is proposed, which allows accepting new reservation requests that overlap the existing reservations under certain conditions. Both the benefits and the risks of the proposed policy are presented theoretically. The experimental results show that the policy can achieve a higher resource utilization rate and lower rejection rate compared to the conventional reservation policy and backfilling technique. In addition, the policy shows better adaptation when the grid systems are in the presence of a high reservation rate.

关键词： grid computing advance reservation reservation violation computing economy

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Boron rings containing planar octa- and enneacoordinate cobalt, iron and nickel metal elements

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science china Chemistry 2008年第7期51卷 607-613页

作者： LUO Qiong school of Chemistry and Chemical engineering, central south university,{3. school of Chemistry and Chemical engineering Central South University Changsha China

For a series of boron rings with planar hyper-coordinate 8th group transition metal atoms, singlet 1FeB8-2, multiplet kFeB9n (n = -1, k = 1; n = 0, k = 2), singlet 1CoB8n(n = -1, +1, +3., multiplet kCoB9n (n = +1, k = 2; n = 0, k = 1) and singlet 1NiB9+, the geometry structures have been optimized to be local minima on corresponding potential hyper-surfaces. The electron structures are discussed by orbital analysis and the aromaticity is predicted by nucleus-independent chemical shifts calculation at both the B3.YP/6-3.1+G* and BP86/6-3.1+G* levels of theory, respectively. The results suggest that all these structures with high symmetry planar geometries are stable and have aromatic properties with six π valence electrons.

关键词： planar hyper-coordinate transition metal DFT

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Effect of aluminum-containing additives on the reactivity in air and CO_2 of carbon anode for aluminum electrolysis

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Rare Metals 2004年第2期23卷 109-114页

作者： LAI Yanqing LI Jie LI Qingyu DING Fengqi school of Metalling science and engineering,{3., changsha 410083. china school of Metallurgy science and engineering Central South University Changsha 410083

Airburn reaction and carboxy reaction result in the excess consumption ofcarbon anode in aluminum electrolysis. To reduce the excess carbon consumption, carbon anode wasdoped with aluminum-containing additives, such as Al, Al_4C_3. AlF_3.and Al_2O_3. Their reactivityin air and CO_2 was determined with an isothermal-gravimetric method to study the effect ofaluminum-containing additives on the reactivity in air and CO_2 of carbon anode. Results shown thatthe airburn reactivity at 450℃ and carboxy reactivity at 970℃ of carbon anode both decreased withAl-containing additives adding, while shown a minimum with the amount of Al_4C_3. AlF_3.and Al_2O_3.ncreasing. However, all Al-containing additives increase the airburn reactivity at 550℃ of carbonanodes. Coke yield measurement and XRD examination with aluminum containing additives doped pitchcokes revealed that the effect of Al-containing additives on the airburn reactivity and carboxyreactivity of carbon anode would result from chemical factors and structural factors.

关键词： aluminum electrolysis aluminum-containing additives reactivity carbonanode

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Mass Concentration of Particles (PM10) in Urban Environment of changsha,china

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湖南大学学报（自然科学版） 2009年第S1期36卷 5-9页

作者： TANG Meng,DENG Qi-hong,WANG Qi(school of Energy science & engineering,{3. south university,changsha,Hunan 410083.china) school of Energy science and engineering Central South University Changsha 410083 China

Continuous measurement of ambient PM10 was performed by TEOM at a university campus for about one year from 20 November 2007 to 29 October 2008 in changsha city of Hunan *** PM10 and PM2.5 concentration were measured by DustTrak simultaneously in order to describe the difference in concentration level and daily variations of particle mass concentration between different seasons,and to survey the influence of ambient particle on indoor air *** the survey period,the annual average PM10 concentration was found to be 117.63.μg/m3.with a mean value 121.88 μg/m3.in winter and 111.50 μg/m3.in *** temporal trend changed quickly from time to time,and the peak values were found in rush hours and in the *** PM10 showed a good correlation with indoor PM10 and outdoor PM2.5 but not with indoor *** results showed that PM10 was influenced by local source(such as traffic or fuel burning)and regional *** correlation analysis has shown that ambient PM10 contributes substantial fraction to indoor PM10 but not to indoor PM2.5,which indicates other source may exist in the indoor environment.

关键词： particle mass concentration human activity relationship

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Determination of phase equilibria in the Ni-Ta-Zr system at 1223.K

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Rare Metals 2003年第3期22卷 160-163页

作者： PAN Ximiao and JIN ZhanpengPhase Diagram and Materials Design Center, school of Materials science and engineering,{3., changsha 410083. china Phase Diagram and Materials Design Center School of Materials Science and Engineering Central South University Changsha 410083

The phase equilibrium relations of the ternary Ni-Ta-Zr system at 1223.K wereinvestigated by means of diffusion triple and electron probe microanalysis (EPMA) techniques. Twoternary compounds were found and a series of tie lines and tie triangles have been determined. Themaximum solubility of Ta in NiZr_2 is about 13.5% (atom fraction). The corresponding tentativeisothermal section at this temperature was constructed based on current experimental information.

关键词： phase diagram diffusion triple nickel EPMA Ni-Ta-Zr system

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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 3.0007,china 2 Department of environmental engineering,school of Metallurgical science and engineering,central south university,changsha 410083.china environmental science Research & Design Institute of Zhejiang Province Hangzhou China Department of environmental engineering School of Metallurgical Science and Engineering Central South University Changsha 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

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On the design of compensator for quantization-caused input-output deviation

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science china(Information sciences) 2011年第4期54卷 824-835页

作者： GUO YuQian,GUI WeiHua & YANG ChunHua school of Information science and engineering,{3. south university,changsha 410083.china school of Information science and engineering Central South University Changsha China

This paper considers the design of compensators for systems with quantized inputs in order to reduce the influence of *** systems with (vector) relative degrees,we propose a kind of compensators which can compensate for the accumulated output deviation completely caused by *** proposed compensators are capable of keeping the differences of the input-output responses between the systems with quantized inputs and the original systems without considering quantization within certain small *** show that the compensators in this paper are robust with respect to model uncertainties,disturbance and measurement noise and can significantly improve the input-output responses of systems with both input quantization and packet dropouts.

关键词： networked control systems quantization packet dropout I/O deviation compensation

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Entropy Assessment on environmental Influence of Condense Heat in Recovery System in Air-Conditioning Refrigerating Machine

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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,{3. 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

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Electrochemical Characterization of Surface-modified LiMn_2O_4 Cathode Materials for Li-ion Batteries

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Journal of Wuhan university of Technology(Materials science) 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 12Mn2O4 was coated with very fine MgO , Al2O3.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 12Mn2O4 spinel at 25℃ and 55 ℃ were tested, using a voltage window of 3.0-4.3. 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 12Mn2O4 coated by metal-oxide has remarkably been improved. The EIS measuremeuts of uncoated and Al2O3.-coated 12Mn2O4 were carried out by a model 273.A potentiostatl galvanistat controUed by a computer using M270 software, and using a freqnency response analyzer （ Zsimpwin ） combined with a potentiostate （ PAR 273.. 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 12Mn2O4 cathode material for lithium batteries.

关键词： lithium-ion batteries surface modification metal-oxide coating: 12Mn2O4 cathode

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