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Acta Oceanologica Sinica 2009年第2期28卷 121-126页

作者： CHEN Jie ZHEN Yu MI Tiezhu YU Zhigang college of Marine Life science Ocean University of China Qingdao 266003 China college of Environmental science and{2. Ocean University of China Qingdao 266100 China college of Chemistry and chemical{2. Ocean University of China Qingdao 266100 China

Prorocentrum donghaiense is an important harmful algae bloom （HAB） causing creature in China＇s seas, and the conventional visual detection can not cope with long-term monitoring and highthroughput sampling projects. An assay for P. donghaiense with sandwich hybridization integrated with nuclease protection assay （NPA-SH） was established. Tests with mixed samples and spiked field ones confirmed its good specificity and sensitivity. The cell number of P. donghaiense correlated well with the optical density, and the regression equation is y=4× 10^- 6x＋ 0.694 9, in which x is the cell number, and y is the optical density, with r2.0.953 5. These results show that the NPA-SH method has good feasibility in the detection of P. donghaiense. Results of NPA-SH and microscopy are excellent for each sample. The NPA-SH method was a simple way in quantitative detection of P. donghaiense, and the whole process could be finished in about six hours, which provided a new approach in high-throughput sampling and long-term monitoring of P. donghaiense.

关键词： Prorocentrum donghaiense ribosomal RNA S1 enzyme sandwich hybridization integrated with nuclease protection assay (NPA-SH)

Study on H atoms diffusion and adsorption properties of MgH_2.V systems

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science China(Technological sciences) 2008年第7期51卷 979-988页

作者： ZHOU DianWu1,2. LIU JinShui3 & PENG Ping3 1 State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan university, Changsha 410082. China 2.college of Mechanical and Automatic{2., Hunan university, Changsha 410082. China 3 college of materials science and{2., Hunan university, Changsha 410082. China 1. State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha 410082 China 2. college of Mechanical and Automatic engineering Hunan University Changsha 410082 China 3. college of materials{2. and engineering Hunan University Changsha 410082 China

Based on experimental results that VH0.81/MgH2.interface was found during the process of mechanically milling MgH2.5at.%V nanocomposite, H atoms diffusion and adsorption properties of MgH2.V systems have been investigated by using a first-principles plane-wave pseudopotential method based on the density functional theory. The results are as follows. When VH/MgH2.interface is formed due to V alloying MgH2.phase, the vacancy formed by H atoms near VH phase region is more stable than that without V alloying, while vacancy near MgH2.phase region is less stable than that without V alloying. During the process of H atoms diffusion after V alloying, the max migration barrier energy of H atoms in MgH2.V systems is reduced compared with that of MgH2.phase, which means that H atoms diffuse easily. When H diffuses into VH from MgH2.across VH/MgH2.interface, among three substitutions such as the replacement of H for V vacancy, or interstitial site or V atoms, the replacement of H for V vacancy has the strongest diffusion ability, next interstitial site, and finally V atoms site. As far as H adsorbed on different surfaces of VH phase is concerned, physical adsorption is carried out more easily than chemical adsorption, and the behavior of H atoms adsorbed on the surface near VH phase region can be found more easily than that near MgH2.phase region.

关键词： plane-wave pseudopotential theory magnesium hydride diffusion adsorption

Effect of Cooling Rate on the Microstructure of ZA48 Alloy

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Journal of Wuhan university of Technology(materials{2.) 2010年第5期25卷 811-813页

作者：王杰芳谢敬佩 School of Physics and engineering The Key Laboratory of Material Physics of the Ministry of Education of China Zhengzhou University The college of materials{2. & engineering Henan University of Science and Technology

The effect of cooling rate on the microstructure of ZA48 alloy was investigated. The alloy was prepared using a relatively simple technique, i e, rapid cooling of the melt in a steel wedge mould. The dependence of microstructure on the cooling rate （about 40 to 10^3 K/s） was determined by the secondary dendrite arm space size measurement, optical microscopy（OM）, and transmission electron microscopy （TEM）. It is found that the matrix structure over a large cooling rate is composed of α-Al dendrite and eutectoid （α＋η）, the size of α-Al dendrite decreases with increasing cooling rate. The relationship between the cooling rate and the secondary dendrite arm space size has been established. TEM shows that a large number of small and dispersed precipitations can be seen in the primary α phase of tip region. Electron diffraction pattern shows that the precipitate phase is Zn3Mg2.phase.

关键词： cooling rate microstructure secondary dendrite arm space size precipitation

Sol-gel preparation and characterization of Li_(1.3)Al_(0.3)Ti_(1.7)(PO_4)_3 sintered with flux of LiBO_2

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Rare Metals 2010年第5期29卷 515-518页

作者： WU Xianming,LI Runxiu,CHEN Shang,HE Zeqiang,and MA Mingyou college of Chemistry and chemical{2.,Jishou university,Jishou 416000,China college of Chemistry and chemical{2. Jishou University Jishou China

Li1.3Al0.3Ti1.7（PO4）3 pellets sintered with different mole fractions of LiBO2.were prepared by sol-gel method. The structural identification, surface morphology, ionic conductivity, and activation energy of the pellets were studied by X-ray diffraction, scanning electron microscopy, and electrochemical impedance spectroscopy. The results show that all the Li1.3Al0.3Ti1.7（PO4）3 pellets sintered with different mole fractions of LiBO2.have similar X-ray diffraction patterns. The sintered pellet becomes denser and the boundary and comer of the particles become illegible with the increase of LiBO2. Among the Lil.3Al0.3Ti1.7（PO3）4 pellets sintered with different mole fractions of LiBO2. the one sintered with 1 mol% LiBO2.shows the highest ionic conductivity of 3.95×10^-4 ***^-1 and the lowest activation energy of 0.2.69 eV.

关键词： phosphates sol-gel process sintering ionic conductivity electrochemical impedance spectroscopy

Effect of Zn^(2.) Content on the Microstructure and Magnetic Properties of Nanocrystalline Ni_(1-x)Zn_xFe_2._4 Ferrite by a Spraying-coprecipitation Method

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Journal of Wuhan university of Technology(materials{2.) 2010年第3期25卷 429-431页

作者：刘银 college of materials{2. and engineering Anhui University of Science and Technology

Nanocrystalline Ni1-xZnxFe2.4 ferrites with 0≤x≤1 were successfully prepared by a spraying-coprecipitation *** microstructure was investigated by using XRD and *** properties were measured with vibrating sample magnetometer（VSM） at room *** results show that the grain size of nanocrystalline Ni1-xZnxFe2.4 ferrite calcined at 600 ℃ for 1.5 h is about 30 *** parameter and specific saturation magnetization Ms of nanocrystalline Ni1-xZnxFe2.4 ferrite increase with the Zn^2. ions content at room temperature,and maximum Ms is 66.8 A·m^2.kg^-1 as the Zn^2. ions content is around 0.5,and coercivity Hc of the nanocrystalline Ni1-xZnxFe2.4 ferrite decreases with Zn^2. ions content.

关键词： nanocrystalline material Ni-Zn ferrite spraying-coprecipitation method magnetic properties microstructure

Investigation on Vibrational Spectra and Structures of 4-Mercaptopyridine Monomer and Its Dihydrate

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chemical Research in Chinese Universities 2006年第1期22卷 90-93页

作者： CHENG Jian-bo 1,2., XUE Wei-qing 1 , ZHAO Bing 1** , ZHANG Gang 3 and GONG Bao-an 2.1. Key Laboratory for Supramolecular Structure and material of Ministry of Education, Jilin university, Changchun 130012. P. R. China 2.{2. and engineering college of Chemistry and Biology, Yantai university, Yantai 2.4005, P. R. China 3. State Key Laboratory of Theoretical and Computational Chemistry, Jilin university, Changchun 13002., P. R. China [a]Key Laboratory for Supramolecular Structure and material of Ministry of Education Jiln University Changchun 130012 P. R. China[b]Science and Engineering College of Chemistry and Biology Yantai University Yantai 264005 P. R. China[c]State Key Laboratory of Theoretical and Computational Chemistry Jiln University Changchun 130023 P. R. China

The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory(DFT), viz. B3LYP method with the 6-311++G(d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the dihydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be consi- derably affected by the water molecules.

关键词： 4MPY Dihydrate Vibrational spectra DFT Molecular structure

Electrochemical performance of LiFePO_4 cathode material for Li-ion battery

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Rare Metals 2006年第z1期25卷 62-66页

作者： LI Shuzhong LI Chao FAN Yanliang XU Jiaqiang WANG Tao YANG Shuting engineering Research Centre for New Power Source materials of Henan Province Xinxiang 453002 China Engineering Research Centre for New Power Source Materials of Henan Province Xinxiang 453002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Engineering Research Centre for New Power Source Materials of Henan Province Xinxiang 453002 China Department of Chemical Engineering College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China

In the search for improved materials for rechargeable lithium batteries, LiFePO4 offers interesting possibilities because of its low raw materials cost, environmental friendliness and safety. The main drawback with using the material is its poor electronic conductivity and this limitation has to be overcome. Here Al-doped LiFePO4/C composite cathode materials were prepared by a polymer-network synthesis technique. Testing of X-ray diffraction, charge-discharge, and cyclic voltammetry were carried out for its performance. Results show that Al-doped LiFePO4/C composite cathode materials have a high initial capacity, good cycle stability and excellent low temperature performance. The electrical conductivity of LiFePO4 material can be obviously improved by doping Al. The better electrochemical performances of Al-doped LiFePO4/C composite cathode materials have a connection with its conductivity.

关键词： lithium ion batteries LiFePO4 doping electrochemical performance

Theoretical study of the mechanism for C-H bond activation in spin-forbidden reaction between Ti^+ and C_2._4

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science China Chemistry 2009年第3期52卷 295-303页

作者： LV LingLing1, LIU XinWen1, YUAN Kun1, WANG XiaoFang1 & WANG YongCheng2.1 college of Life science and Chemistry, Tianshui Normal{2., Tianshui 741001, China 2.college of Chemistry and chemical engineering, Northwest Normal{2., Lanzhou 730070, China college of Life science and Chemistry Tianshui Normal University Tianshui 741001 China college of Chemistry and chemical{2. Northwest Normal University Lanzhou 730070 China

The mechanism of the spin-forbidden reaction Ti+(4F, 3d2.s1) + C2.4 → TiC2.2. (2.2. + H2.on both doublet and quartet potential energy surfaces has been investigated at the B3LYP level of theory. Crossing points between the potential energy surfaces and the possible spin inversion process are discussed by means of spin-orbit coupling (SOC) calculations. The strength of the SOC between the low-lying quartet state and the doublet state is 59.3 cm-1 in the intermediate complex IM1-4B2. Thus, the changes of its spin multiplicity may occur from the quartet to the doublet surface to form IM1- 2.1, leading to a sig-nificant decrease in the barrier height on the quartet PES. After the insertion intermediate IM2. two dis-tinct reaction paths on the doublet PES have been found, i.e., a stepwise path and a concerted path. The latter is found to be the lowest energy path on the doublet PES to exothermic TiC2.2. (2.2. + H2.products, with the active barrier of 4.52.kcal/mol. In other words, this reaction proceeds in the following way: Ti++C2.4 →4IC→IM1-4B2.4,2.SC→IM1- 2.1→[2.Sins]→IM2.[2.SMCTS]→IM5→TiC2.2.(2.2.+H2.

关键词： Ti+(4F) and C2.4 spin-forbidden reaction mechanism spin-orbit coupling (SOC) concerted path

Biological decomposition of Na_2._2._3 into sulfur by a newly isolated facultative thermophilic alkaline desulphuricant strain

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science China Chemistry 2009年第2期52卷 226-230页

作者： ZHANG JianBin1,ZHANG Tong2.MA Kai2.ZHANG PengYan2.LI Qiang2.& WEI XiongHui1 1 Department of Applied Chemistry,college of Chemistry & Molecular engineering,Peking{2.,Beijing 100190,China 2.college of chemical engineering,Inner Mongolia{2. of Technology,Huhhot 010051,China 1. Department of Applied Chemistry College of Chemistry & Molecular Engineering Peking University Beijing 100190 China 2. college of chemical{2. Inner Mongolia University of Technology Huhhot 010051 China

A facultative thermophilic alkaline desulphuricant strain named GDJ-3 was isolated from neutral soils,enriched on sulfur synthetic medium,and detected in previous *** and chemotax-onomic analyses and 16s RNA gene sequencing showed that the strain was in good agreement with Alpha proteobacterium sp.(97%) and ochrobactrum sp.(98%).The regenerative processes of the solu-tion containing sulfur compounds(SCS) from the strain through an orthogonal test were investigated to get the optimum regenerative *** results showed that regenerative temperature,air flow,and stirring speed of the agitator were the main three variables influencing the regenerative processes of the *** optimum regenerative efficiency of the SCS from the strain was obtained when tem-perature,air flow,and stirring speed of the agitator were 318.2.K,3.0 L/min,and zero r/min,*** this condition,when the cell concentration of the strain was adjusted to 107/mL,the concentra-tions of Na2.2.3 and Na2. in the SCS decreased from 112.68 g/L to 96.88 g/L and from 0.87 g/L to 0.11 g/L in 9.5 ***,XRD spectrum shows that sulfur was formed in the regeneration *** results suggest that the strain has potential application to the regeneration of the industrial so-lution containing sulfur compounds.

关键词： bio-desulfurization thermophiles optimization biocomposition orthogonal test