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THE SENSITIVITY OF RESPONSE SIGNAL OF SPECTROELECTROchemistry(SEC)

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Chinese chemical Letters 1992年第6期3卷 465-466页

作者： Yuan Bao ZHU Qing Ji XIE Lian Hong CHEN Shuang E HE Department of chemistry and chemical engineering,{3., changsha 4.0082.

In this paper, we propose the use of the molar absorbance/ potential ratio to measure quantitatively the sensitivity of response signal of SEC cell and the system under study. A simple equation was developed, and the major factors influencing the sensitivity were also assessed. The results obtained this way were in good agreement with actual cases.

关键词： SEC THE SENSITIVITY OF RESPONSE SIGNAL OF SPECTROELECTROchemistry length

Effects of chemical coating with Ni on electrochemical properties of Mg_2Ni hydrogen storage alloys

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Rare Metals 2007年第6期26卷 611-616页

作者： TANG Yougen SHEN Jianbin XU Yijun JIANG Jinzhi chemistry and chemical engineering School Central South University Changsha 410083 China

The effects of nickel coating on the electrochemical properties of Mg2Ni hydrogen storage alloys are presented in this paper. X-ray diffraction （XRD） and scanning electron microscope （SEM） techniques were employed to examine the crystal structure and surface morphologies of the bare and Ni-coated Mg2Ni alloys. The electrochemical properties of alloys were characterized by cyclic voltammetry （CV） and dectrochemical impedance spectroscopy （EIS）. The results showed that Ni coating not only decreased the charge transfer resistance, but also decreased the H atom diffusion resistance for Mg2Ni alloys. It was also found that Ni coating effectively improved the discharge capacity, but decreased the cycling performance of the as-synthesized Ni-coated MgzNi alloys. The discharge current has a great impact on the cycling perform- ance of the as-synthesized Ni-coated Mg2Ni alloys.

关键词： hydrogen storage alloys chemical coating cyclic voltammetry electrochemical impedance spectroscopy

Enhancement in Activity of a Vanadium Catalyst for the Oxidation of Sulfur Dioxide by Radio Frequency Plasma During the Preparation Process

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Journal of Natural Gas chemistry 2003年第3期12卷 195-200页

作者： Zhenxing Chen, Honggui Li, Lingsen WangState Key Laboratory for Powder Metallurgy, College of chemistry and chemical engineering, Central South {3., changsha 410083. china State Key Laboratory for Powder Metallurgy College of Chemistry and Chemical Engineering Central South University

Radio frequency plasma was used to prepare a vanadium catalyst. The resultsshowed that activating time of the catalyst could be shortened quickly and the catalytic activitywas improved to some extent with the use of plasma. Catalyst Ls-9 was prepared under an optimalcondition of 40 W discharge power, 10 min discharge time and 8 Pa gas pressure. The catalyticactivity was up to 54.7% at 410℃, which was 2.2% higher than that of the Ls-8 catalyst. Only 10 minwas needed to activate the catalyst with plasma, which was 1/9 of the traditional calcination *** Ls-9, both the endothermic as well as the exothermic peaks detected by differential thermalanalysis shifted to higher temperatures obviously, indicating that its crystal phase could melteasily. There existed an apparent endothermic peak at 283.. SEM photographs showed a uniform sizedistribution. It is inferred that the quadrivalent vanadium compound may exist mainly in the form ofVOSO_4.

关键词： plasma activation dispersion vanadium catalyst low-temperature activity

Facile synthesis of La_2Mo_2O_9 nanoparticles via an EDTA complexing approach

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Rare Metals 2008年第4期27卷 340-344页

作者： CHENG Hua WANG Hongen LI Liang LU Zhouguang QIAN Dong College of chemistry and chemical engineering Central South University Changsha 410083 China State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

A facile EDTA （ethylene diamine tetraacetic acid） complexing technique has been successfully employed to prepare La2Mo2O9 nanoparticles. The as-synthesized products are characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and Fourier transform infrared spectroscopy （FT-IR）. The results show that a homogeneous transparent gel can be obtained with EDTA as the organic complexing reagent under the pH value of 3.0. Further thermal decomposition of the as-synthesized transparent gel by increasing the temperature up to 600℃ for 3.h results in the formation of La2Mo2O9 nanoparticles with a crystal size of about 3. nm. Moreover, the nanoparticles tend to form micrometer-sized aggregates with a three-dimensional network structure, which shows promising applications in solid oxide fuel cells （SOFC）, catalysts and so on.

关键词： inorganic non-metal materials EDTA complexing sol-gel La2Mo2O9 nanoparticles porous structure

Activity Enhancement of Vanadium Catalysts with Ultrasonic Preparation Process for the Oxidation of Sulfur Dioxide

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Journal of Natural Gas chemistry 2003年第2期12卷 139-144页

The effect of ultrasonic cavitations on the activity of vanadium catalysts atlow temperatures for the oxidation of sulfur dioxide, in which refined carbonized mother liquor hadbeen added, was investigated. Twenty minutes were needed to produce obvious cavitations when thecatalyst raw material was treated in the 50 W ultrasonic generator. However, only 10 minutes wouldbe needed in a 150 W ultrasonic generator. The higher the temperature of the wet material, the lesstime was needed to produce cavitations, and the optimal temperature was 60℃. The water content inthe wet material mainly affected the quantity of cavitations. Ls-8 catalyst was prepared usingultrasonic. Its activity for conversion of SO_2 reached to 52.5% at 410℃ and 4.2% at 3.0℃. Thedifferential thermal analyses indicate that both endothermic peaks and exothermic peaks noticeablyshifted forward compared with Ls catalyst prepared without ultrasonic, and SEM results show auniform pore size distribution for Ls-8 catalyst.

关键词： ultrasonic dispersion vanadium catalyst low temperature activity sulfurdioxide cavitation

SYNTHESIS AND APPLICATION OF ANTIMONY N,N-DIETHYLDITHIOCARBAMATE

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中国有色金属学会会刊：英文版 1996年第3期6卷 54-57页

作者： Qu Long Zhang Min Li Li Shu Wanyin(Department of chemistry,Central South university of Technology, changsha 410083. CENT S UNIV TECHNOL DEPT CHEMCHANGSHA 410083PEOPLES R CHINA

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关键词： N N-diethyldithiocarbamate preparation stability extreme pressure and wear resistance

Behavior of mixed ZnO and SiO2 nano-particles in magnetic field assisted fluidization

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Particuology 2007年第Z1期 169-173页

作者： Ping Zenga, Tao Zhoua, Guanqun Chena, Qingshan Zhub a School of chemistry and chemical engineering, Central South {3., changsha 410083. hunan, china b Institute of Process engineering, Chinese Academy of Sciences, Beijing 100080, china

The fluidization behavior of ZnO nano-particles in magnetic fluidized bed (MFB) by adding coarse magnetic particles was investigated, followed by the co-fluidization of mixtures of ZnO and SiO2 nano-particles. For such co-fluidization, bed expansion was found to change smoothly with gas velocity through a range of stable operation. By measuring the bed expansion ratio and pressure drop, a stability diagram for the mixture in MFB was obtained. Within this stable operation range, with increasing gas velocity the pressure drop hardly changes as the bed expands, up to an expansion ratio of more than 4.

关键词： Nano-particle Fluidization Magnetic fluidized bed Coarse magnet Mixture

Effects of water phase concentration on the emulsion polymerization of polyaniline

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Journal of Central South university of Technology 2001年第2期8卷 140-142页

作者： PAN Chun yue 1,CHEN Zhen hua 2,HUANG Yong li 1,HUANG Ke long 1 (1.College of chemistry and chemical engineering, Central South {3., changsha 410083. china 2.Department of Materials Science and engineering, Central South {3., Cha 1. College of chemistry and chemical engineering Central South University 410083 Changsha China 2. Department of Materials Science and engineering Central South University 410083 Changsha China

The emulsion polymerization of aniline in three phase system of xylene functionalized protonic acid water was carried out using (NH 4) 2S 2O 4 as oxidant. The influences of water phase concentration on the viscosity, conductivity, transmittance of polyaniline(PAN) latex and its powders were studied. The results show that the properties of PAN prepared through the emulsion polymerization are influenced by the amount of water used in the polymerization. The morphology of PAN varies with the water phase concentration used in the polymerization, which may result in the change of properties of PAN latex and its powders. When the volume fraction of water (φ) is about 20% 3.%, the prepared PAN powder has higher conductivity, and the PAN latex has appropriate viscosity and particle size. The consumption of xylene was reduced at high φ value.

关键词： polyaniline emulsion polymerization water concentration property

A STUDY ON Ti ELECTRODE MODIFIED BY NICKEL ION BEANS

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Chinese chemical Letters 1991年第3期2卷 251-252页

作者： Ji Shuang ZHANG Rong Hui WANG Yao Jiao LU Han Ming FENG,Jin Quan YANG Department of chemistry and chemical engineering,{3. university changsha,4.0082

The reduction of H^+ on Ti electrodes which were treated by implanting nickel ions and thermodiffusing in vacuum has been *** calytic activity of the afore- mentioned electroes for H^+ reduction is much higher than th... 详细信息

关键词： Ti A STUDY ON Ti ELECTRODE MODIFIED BY NICKEL ION BEANS ION