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Composite Cathode Bi_(1.14.sr_(0.4.)O_(2.14.-Ag for Intermediate-temperature solid Oxide Fuel Cells

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Journal of wuhan university of Technology(materials science) 2008年第3期23卷 350-353页

作者：高展张萍 faculty of material science and chemical Engineering China University of Geosciences

Composites consisting of strontium stabilized bismuth oxide （Bi1.14.r0.4.O2.14. ssB） and silver were investigated as cathodes for intermediate-temperature solid oxide fuel cells with doped ceria electrolyte. There were no chemical reactions between the two components. The microstructure of the interfaces between composite cathodes and Ce0.8sm0.2O1.9 （sDC） electrolytes was examined by scanning electron microscopy （sEM）. Impedance spectroscopy measurements show that the performance of cathode fired at 700 ℃ is the best. When the content of Ag2O is 70 wt%, polarization resistance values for the ssB-Ag cathodes are as low as 0.2 Ωcm^2 at 700℃ and 0.29 Ωcm^2 at 650℃. These results are much smaller than some of other reported composite cathodes on doped ceria electrolyte and indicate that ssB-Ag composite is a potential cathode material for intermediate temperature sOFCs.

关键词： solid oxide fuel cells (sOFCs) composite cathode strontium stabilized bismuth oxide (ssB) samaria doped ceria (sDC)

Research on semi-solid slurry of a hypoeutectic Al-si alloy prepared by low superheat pouring and weak electromagnetic stirring

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Rare Metals 2006年第2期25卷 177-183页

作者： LIU Zheng MAO Weiming ZHAO Zhengduo material of science and Engineering school University of Science and Technology Beijing Beijing 100083 China faculty of material and chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 China

The semi-solid slurry of a hypoeutectic Al-si alloy was manufactured by low superheat pouring and weak electromagnetic stirring. The effects of pouting temperature and stirring power on the semi-solid slurry were investigated. The results indicated that the semi-solid slurry to satisfy rheocasting can be manufactured by low superheat pouring and weak electromagnetic stirring. The pouring temperature （or superheat） and the stirring power remarkably affected the morphology of primary α-Al and the size of primary α-Al, and there is no obvious effect of stirring time on primary α-Al. Compared with the samples made by low superheat pouring with no stirring, the nucleation rate, particle morphology and grain size of primary α-Al in A356 were markedly improved by low superheat pouring and weak electromagnetic stirring. On the condition of weak electromagnetic stirring, the pouring temperature with low superheat can be suitably raised to reach the effectiveness obtained from the lower pouring temperature without stirring.

关键词： semi-solid low superheat pouring weak electromagnetic stirring hypoeutectic Al-si alloy A356 Al alloy

sYNTHEsIs OF NOVEL THIOPHENEDIMETHYLENE BRIDGED HOMOBINUCLEAR METALLOCENEs AND THEIR CATALYTIC PROPERTIEs FOR ETHYLENE POLYMERIZATION

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Chinese Journal of Polymer science 2006年第1期24卷 21-27页

作者： Xi-jie Liu Jun-quan sun Hai-ying Zhang Xiao-hui Xiao and Feng Lin Department of chemical Engineering,College of material and chemical Engineering,Zhejiang university,Hangzhou 310027,{4. Zhejiang Univ Coll Mat & Chem Engn Dept Chem Engn Hangzhou 310027 Peoples R China

By treating disodium（thiophenedimethylene）dicyclopentadienide C4.2s（CH2C5H4.a）2 with two equivalent of CpTiCl3 or CpZrC13 DME at 0℃ in THF, two new thiophenedimethylene bridged binuclear metallocenes [Cl2MC5H5][C5H4.H2C4.2sCH2C5H4.[C5H5MCl2] （M = Ti 3, M = Zr 4. were synthesized in high yield and their structures were characterized by ^1H-NMR. These complexes were used as catalysts for ethylene polymerization in the presence of methylaluminoxane （MAO）. The effects of polymerization temperature, time, concentration of catalyst, molar ratio of MAO/Cat on polymerization were studied in detail. The catalytic activities of thiophenedimethylene bridged binuclear metallocene catalysts （3, 4. reached 2.4. × 10^5 g PE mol^-1 cat^-1· h^-1, 9.61 × 10^5 g PE mol^-1 · cat^-1· h^-1 respectively, which are higher than that of pheneyldimethylene bridged binuclear metallocene catalysts and much higher than that of corresponding mononuclear metallocenes （Cp2TiCl2 and Cp2ZrCl2）. The molecular weight distribution curves of polyethylenes produced by binuclear metallocene catalysts （3, 4. and by mononuclear metallocene catalyst have only single peak, but the former （MWD = 3.5-4.7） is obviously broader than the latter （MWD = 2.0-2.2）.

关键词： Binuclear metallocene Thiophenedimethylene bridged Ethylene polymerization.

Garnet-bearing Granulite Facies Rock Xenoliths from Late Mesozoic Volcaniclastic Breccia, Xinyang, Henan Province

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Acta geologica sinica(English Edition) 2001年第4期75卷 445-451页

作者： ZHENG Jianping, sUN Min, LU Fengxiang, WANG Chunyangand ZHONG Zengqiu faculty of Earth sciences, china university of geosciences,{4. Department of Earth sciences, The university of Hong Kong, china faculty of Earth sciences China University of Geosciences Wuhan 430074 China Department of Earth sciences The University of Hong Kong China [?]3Zheng Jianping Born in 1964 graduated from the china university of geosciences (wuhan) with a PhD degree in 1997 mainly engaged in teaching and scientific researches on petrology and chemical geodynamics. E-mail: jpzheng@***.

This paper presents the primary results of petrologic, mineralogical and petrochemical studies of garnet-bearing granulite facies rock xenoliths from Xinyang, Henan Province. These xenoliths, which are found in a pipe of late Mesozoic volcaniclastic breccia, are of high density (3.13–3.30 g/cm3) and high seismic velocity (Vp = 7.04.7.31 km/s), being products of underplating of basaltic magmas and had experienced granulite facies metamorphism. The underplating and metamorphism took place before the eruption of the host rock. Petrographical studies and equilibrium T-P calculations show that these xenoliths were captured at a 4. km depth and experienced at least a 16 km uplift before they were captured. The dynamics of the uplift could be related to the continent-continent collision between the North china plate and the Yangtze plate during the Triassic.

关键词： granulite facies mafic rock xenolith uplift Xinyang

sYNTHEsIs AND OPTICAL PROPERTIEs OF A NOVEL ORGANIC/INORGANIC HYBRID NONLINEAR OPTICAL POLYMER VIA sOL-GEL PROCEss

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Chinese Journal of Polymer science 2001年第4期19卷 421-427页

作者： Hong-xia Xi Zhong Li Zhao-xi Liang The Institute of chemical Engineering south china university Guangzhou 51064. china The Institute of Polymer science, Zhongshan university Guangzhou 510275, china s china Univ Inst Chem Engn Canton 510640 Peoples R China Zhongshan Univ Inst Polymer Sci Canton 510275 Peoples R China

A new organic/inorganic hybrid nonlinear optical (NLO) material was developed by the sol-gel process of an alkoxysilane dye with tetraethoxysilane. A NLO moiety based on 4.nitro-4.' -hydroxy azobenzene was covalently bonded to the triethoxysilane derivative, i.e, gamma -isocyanatopropyl triethoxysilane. The preparation process and properties of the sol-gel derived NLO polymer were studied and characterized by sEM, FTIR,H-1-NMR, UV-Vis, DsC and second harmonic generation (sHG) measurement. The results indicated that the chemical bonding of the chromophores to the inorganic siO2 networks induces low dipole alignment relaxation and preferable orientational stability. The sHG measurements also showed that the bonded polymer film containing 75 wt% of the akoxysilane dye has a high electro-optic coefficient (r(33)) of 7.1 pm/V at 1.1 mum wavelength, and exhibit good sHG stability, the r(33) values can maintain about 92.7% of its initial value at room temperature for 90 days, and can maintain about 59.3% at 100 degreesC for 300 min.

关键词： sol-gel process nonlinear optical material alkoxysilane dye dipole alignment relaxation chromophore

Complexity and self-Organized Criticality of solid Earth system(Ⅰ)

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Journal of Earth science 1998年第1期17卷 30-47页

作者： Yu Chongwen faculty of Earth sciences, china university of geosciences, {4. 4.0074

The author puts forward the proposition of Complexity and self Organized Criticality of solid Earth system in the light of: (1) the science of complexity studies the mechanisms of emergence of complexity and is the science of the 21st century, (2) the study of complexity of the earth system would be one of the growing points occupying a strategic position in the development of geosciences in the 21st century. By the proposition we try to cogitate from a new viewpoint the ancient yet ever new solid earth system. The author abstracts the fundamental problem of the solid earth system from the essence of the generalized geological systems and processes which reads: the complexity and self organized criticality of the global nature, structure and dynamical behavior of the whole solid earth system emerging from the multiple coupling and superposition of non linear interactions among the multicomponents of the earths material and the multiple generalized geological (geological, geophysical, and geochemical) processes . starting from this cognizance the author proposes eight major themes and the methodology of researches on the complexity and self organized criticality of the solid earth system.

关键词： complexity self organization self organized criticality the solid earth system fractal chaos long range spatio temporal correlation fractal spatio temporal structure.

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sYNTHEsIZING KINETICs AND MICRO-CHARACTERIZATION OF sPINEL LiMn_(2)O_(4. FOR LITHIUM-ION BATTERY CATHODE material

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Acta Metallurgica sinica(English Letters) 2001年第5期14卷 323-329页

作者： CATHODE material M.s. Zhao, Y.C. Zhai and Y.W. Tian school of material & Metallurgy, Northeastern university, shenyang 110004. china school of material & Metallurgy Northeastern University

The reaction process during synthesis of LiMn2O4.with LiOH·H2O and MnO2 was studied by means of DTA in dynamical air atmosphere, and it could be applied as an important theoretical principle for preparing LiMn2O4. The active energies of four reaction processes were obtained with Doyle-Ozawa method and Kissinger method as follows: 66.299, 72.64., 128.11 and 113.876 kJ·mol-1, respectively. Reaction orders, frequency factors and kinetic equations of each reaction were determined by Kissinger method. XRD, sEM and TEM show that the synthesized LiMn2O4.is a pure phase, with regular appearance and higher ratio-surface.

关键词： Cathodes Inorganic compounds Kinetic theory synthesis (chemical)

Modification of Fluorgypsum as Cement Retarder

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Journal of wuhan university of Technology(materials science) 2007年第4期22卷 745-748页

作者：王锦华 school of materials science and Engineering Wuhan University of Technology

The chemical composition and mineral structure of fluorgypsum as well as its harm to application in cement were elaborately analyzed. The primary fluorgypsum was modified and its applications in cement＇s production were studied. The technological flow chart of preparing modified fluorgypsum was given. Experimental results indicate that hydration ratio the modified fluorgypsum through adding compound additive for 14. is about 70%. The modified fluorgypsum as cement retarder has certain stimulation to fly ash and increases the strength of compound cement. In addition, its adding amount is lower than that of natural gypsum. The modified fluorgypsum is a good substitute for natural gypsum.

关键词： fluorgypsum industry waste modification cement retarder

Reply to“Comment on ‘Recent progress in thermodynamics of radiation—Exergy of radiation,effective temperature of photon and entropy constant of photon'”

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science china(Technological sciences) 2010年第3期53卷 878-880页

作者： CHEN Zeshao 1,MO songPing 1,2 &HU Peng 1 1Department of Thermal science and Energy Engineering,university of science and Technology of china,Hefei 230027,china 2 faculty of {4. and Energy,Guangdong university of Technology,Guangzhou 510006,china 1. Department of Thermal science and Energy Engineering University of Science and Technology of China Hefei 230027 China2. Faculty of Material and Energy Guangdong University of Technology Guangzhou 510006 China

Two counterexamples in Liu's comment on'Recent Progress in Thermodynamics of Radiation—Exergy of radiation,effective temperature of photon and entropy constant of photon'are analyzed and the incorrect applications of the related concepts are *** similarities and differences between the concepts of the effective temperature of photon,the exergy of spectral radiation,the entropy constant of photon and the macroscopic concepts of temperature,exergy,and entropy are further *** duality of radiant energy,micro-state quantum characteristic and macro-state thermal characteristic is presented.

关键词： thermodynamics of radiation photon entropy