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A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2:F film optically transparent electrode

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science china Chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2 & NIU Shuyan1,2 1. College of Chemistry and molecular Engineering, Qingdao university of science and technology, Qingdao 266042, china 2. College of Chemistry and Chemical Engineering, Ocean university of china, Qingdao 266003, china Correspondence should be addressed to Jiao Kui 1. College of Chemistry and molecular Engineering Qingdao University of Science and Technology 266042 Qingdao China 2. College of Chemistry and Chemical Engineering Ocean University of China 266003 Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2:F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to < 4.0, and two successive one-electron electrooxidation processes in the pH range from 4.0 to < 7.0 in the B-R buffer solution. At pH 6.5, the electrooxidative product of TMB generated a subsequent chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

Preparation of grain size controlled boron-doped diamond thin films and their applications in selective detection of glucose in basic solutions

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science china Chemistry 2010年第6期53卷 1378-1384页

作者： ZHAO JianWen1,2,WANG JinLiang3,ZHI JinFang3 & ZHANG ZhiMing4 1College of Chemistry and Chemical Engineering,Jishou university,Jishou 416000,china 2Schools of Materials science and Engineering,Nanyang Technological university,639798,Singapore 3Laboratory of Organic Optoelectronic Functional Materials and molecular Engineering,Technical Institute of Physics and Chemistry & Graduate university of Chinese Academy of sciences,Beijing 100080,china 4Research Institute of Micro-Nano science and technology,Shanghai Jiao Tong university,Shanghai 200030,china 1. College of Chemistry and Chemical Engineering Jishou University Jishou 416000 China2. Schools of Materials Science and Engineering Nanyang Technological University 639798 Singapore Singapore3. Laboratory of Organic Optoelectronic Functional Materials and Molecular Engineering Technical Institute of Physics and Chemistry & Graduate University of Chinese Academy of Sciences Beijing 100080 China4. Research Institute of Micro-Nano Science and Technology Shanghai Jiao Tong University Shanghai 200030 China

Boron-doped diamond (BDD) thin films with different crystal grain sizes were prepared by controlling the reacting gas pressure using hot filament chemical vapor deposition (HFCVD).The morphologies and structures of the prepared diamond thin films were characterized by scanning electron microscopy (SEM) and Raman *** electrochemical responses of K4Fe(CN)6 on different BDD electrodes were *** results suggested that electron transfer was faster at the boron-doped nanocrystalline diamond (BDND) thin film electrodes in comparison with that at other BDD thin film *** prepared BDD thin film electrodes without any modification were used to directly detect glucose in the basic *** results showed that the as-prepared BDD thin film electrodes exhibited good selectivity for detecting glucose in the presence of ascorbic acid (AA) and uric acid (UA).The higher sensitivity was observed on the BDND thin film grown on the boron-doped microcrystalline diamond (BDMD) thin film surface,and the linear response range,sensitivity and the low detection limit were 0.25–10 mM,189.1 μA mmol-1 cm-2 and 25 μM (S/N=3) for glucose in the presence of AA and UA,respectively.

关键词： diamond thin films electrochemical properties selective glucose detection

A possible mode of the specific recognition of nucleic acids by proteins

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Chinese science Bulletin 2001年第11期46卷 930-934页

作者： LI Xuqing & LIU CiquanDepartment of Computer science, Kunming university of science and technology, Kunming 650041, china Laboratory of cellular and molecular Evolution, Kunming Institute of Zoology, Chinese Academy of sciences, Kunming 650223, china Yunnan Observatory, Chinese Academy of sciences, Kunming 650011, china 4. Modern Biological Center, Yunnan university, Kunming 650091, china Department of Computer science Kunming University of Science and Technology Kunming China Yunnan Observatory Chinese Academy of Sciences Kunming China Laboratory of cellular and molecular Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming China Modern Biological Center Yunnan University Kunming China

Seven sets of protein target sites, which occur in several gene promoters, have been analyzed. The results suggest that there is a possible mode of specific recognition of double-helical nucleic acids by proteins. This recognition mode is related to a special topological property of double-helical DNA, which is termed base spatial pattern (BSP) of DNA segment. BSP is the spatial topological property determined only by the spatial arrangement of the bases on double-helical DNA segment.

关键词： protein nucleic acids recognition base spatial pattern (BSP) target sites.

Investigation on performance of a solar thermophotovoltaic system

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science china(Technological sciences) 2008年第12期51卷 2285-2294页

作者： CHEN Xue, XUAN YiMin & HAN YuGe School of Power Engineering, Nanjing university of science & technology, Nanjing 210094, china School of Power Engineering Nanjing University of Science & Technology Nanjing 210094 China

In the light of the thermo-electric conversion principle, a model for predicting the performance of a solar thermophotovoltaic system is presented. The temperature distributions of the emitter for different concentrator ratios are numerically computed and the influence of the concentrator ratio on the system performance is analyzed. Numerical results show that the emitter temperature and the system efficiency increase with increase of the concentrator ratio. The effects of some other factors such as the spectral filter, cell temperature, and the reflectivity of the top and bottom surfaces of the emitter on the conversion performance of the STPV system are discussed.

关键词： STPV emitter temperature system efficiency

Inhibition of ethanol-induced toxicity by tanshinone ⅡA in PC12 cells

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Acta Pharmacologica Sinica 2006年第6期27卷 659-664页

作者： Xian-fang MENG~2 Xiao-jing ZOU~3 Bin PENG~2 Jing SHI~2 Xin-min GUAN~2 Chun ZHANG~(4,5)2 Department of Neurobiology,Tongji Medical College,Huazhong university of science and technology,Wuhan 430030,china 3 Department of Anesthesiology,4 Department of Nephrology,Union Hospital,Tongji Medical College,Huazhong university of science and technology,Wuhan 430022.china Department of Neurobiology Tongji Medical College Huazhong University of Science and Technology Wuhan China Department of Anesthesiology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China Department of Nephrology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China

Aim:To observe the effects of tanshinone IIA(Tan IIA)on the neurotoxicityinduced by ethanol in PC 12 cells and to explore its protective ***:PC 12cell survival was measured by MTT *** formation of reactive oxygenspecies(ROS)and lactate dehydrogenase(LDH)release were detected by 2′,7′-dichlorofluorescin(DCF)fluorescence and calorimetric method,*** of cell apoptosis was monitored by flow *** expression ofp53 was detected by immuno-fluorescence and flow ***:Ethanolsignificantly impaired the survival of PC12 cells as demonstrated by MTT *** also induced significant ROS formation and increased LDH ***-incubation with Tan IIA in the culture medium significantly reversed these *** caused cell apoptosis and the upregulation of p53 *** anti-apoptosis effects of Tan IIA on ethanol-induced toxicity were accompanied by thedownregulation of pro-apoptotic p53 protein ***:Tan IIAcan protect neurons from apoptosis and might serve as a potential therapeuticdrug for neurological disorders induced by ethanol.

关键词： apoptosis ethanol PC12 cells p53 tanshinone ⅡA

PREDICTION ON THE THERMODYNAMIC PROPERTIES OF TERNARY LIQUID ALLOYS BY MODIFIED COORDINATION EQUATION

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 241-247页

作者： D.P. Tao School of Materials and Metallurgical Engineering, Kunming university of science and technology, Kun-ming 650093, china Sch. of Mat. Eng. Kunming Univ. of Sci. and Technol. Kunming 650093 China

The coordination numbers in the molecular Interaction Volume Model can be calcu-lated from the common physical quantities of pure matters.A significant advantage ofthe model lies in its ability to predict the thermodynamic properties of ternary liqmdalloys using only the binary infinite dilute activity coefficients,and the predicted values are in good agreement with the experimental data of ternary liquid alloys,whichshows that the model is reliable,convenient and economic.

关键词： thermodynamic property ternary liquid alloy molecular inter-action volume model modified coordination eguation

Theoretical study of ZnO adsorption and bonding on Al_2O_3(0001) surface

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science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 664-675页

作者： LI Yanrong1,YANG Chun1,2,XUE Weidong1,LI Jinshan3 & LIU Yonghua3 1.Institute of Microelectronics and Solid State Electronics,university of Electronic science and Technol- ogy of china,Chengdu 610054,china 2.Institute of Mathematics and Software science,Sichuan Normal university,Chengdu 610068,china 3.Institute of Chemical Materials,china Academy of Engineering Physics,Mianyang 621000,china Institute of Microelectronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Institute of Mathematics and Software science Sichuan Normal University Chengdu 610068 China Institute of Chemical Materials China Academy of Engineering Physics Mianyang 621000 China

ZnO adsorption on sapphire (0001) surface is theoretically calculated by using a plane wave ultrasoft pseudo-potential method based on ab initio molecular dynamics. The results reveal that the surface relaxation in the first layer Al-O is reduced, even eliminated after the surface adsorption of ZnO, and the chemical bonding energy is 434.3(±38.6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 30° angle away from the adjacent Al-O bond, and the stable chemical adsorption position of the Zn is deflected from the surface O-hexagonal symmetry with an angle of about 30°. The analysis of the atomic populations, density of state and bonding electronic density before and after the adsorption indicates that the chemical bond formed by the O2 of the ZnO ? and the surface Al3+ has a strong ionic bonding characteristic, while the chemical bond formed by the Zn2+ and the surface O2 has an obvious covalent characteristic, which ? comes mainly from the hybridization of the Zn 4s and the O 2p and partially from that of the Zn 3d and the O 2p.

关键词： α-Al2O3 (0001) ZnO ab initio molecular dynamics chemical adsorption density of states

Study on Tribological Properties of Irradiated Crosslinking UHMWPE Nano-Composite

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Journal of Bionic Engineering 2009年第1期6卷 7-13页

作者： Lei Xiong, Dang-sheng Xiong, Jia-bo JinDepartment of Materials science and Engineering, Nanjing university of science and technology, Nanjing 210094, P. R. china [a]Department of Materials science and Engineering Nanjing University of Science and Technology Nanjing 210094 P. R. China

Ultra High molecular Weight Polyethylene(UHMWPE)has been widely used as a bearing material for artificial joint replacement over forty *** is usually crosslinked by gamma rays irradiation before its implantation into human *** this study,UHMWPE and UHMWPE/nano-hydroxyapatite(n-HA)composite were prepared by vacuum hot-pressing *** prepared materials were irradiated by gamma rays in vacuum and molten heat treated in vacuum just after *** effect of filling n-HA with gamma irradiation on tribological properties of UHMWPE was investigated by using friction and wear experimental machine(model MM-200)under deionized water ***-morphology of worn surface was observed by metallographic *** angle and hardness of the materials were also *** results show that contact angle and hardness are changed by filling n-HA and gamma *** coefficient and wear rate under deionized water lubrication are reduced by filling *** friction coefficient is increased and wear rate is reduced significantly by gamma *** worn surface of unfilled material is mainly characterized as adhesive wear and abrasive wear,and that of n-HA filled material is mainly characterized as abrasive *** gamma irradiation,the degrees of adhesive and abrasive wear for unfilled material and abrasive wear of n-HA filled material are significantly *** and filled materials after irradiation are mainly shown as slight fatigue *** results indicate that UHMWPE and UHMWPE/n-HA irradiated at the dose of 150 kGy can be used as bearing materials in artificial joints for its excellent wear resistance compared to original UHMWPE.

关键词： tribological properties irradiated crosslinking UHMWPE n-HA artificial joints

INTEGRATED LAYOUT DESIGN OF cellS AND FLOW PATHS

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Chinese Journal of Mechanical Engineering 2003年第3期16卷 225-228页

作者： Li Zhihua Zhong Yifang Zhou Ji CAD Center, Huazhong university of science and technology,Wuhan 430074, china CAD Center Huazhong University of Science and Technology Wuhan 430074 China

The integrated layout problem in manufacturing Systems is investigated. Anintegrated model for Concurrent layout design of cells and flow paths is formulated. A hybridapproach combined an enhanced branch-and-bound algorithm with a simulated annealing scheme isproposed to solve this problem. The integrated layout method is applied to re-layout the gear pumpshop of a medium-size manufacturer of hydraulic pieces. Results show that the proposed layout methodcan concurrently provide good solutions of the cell layouts and the flow path layouts.

关键词： Facility layout Integrated layout design Material flow network Manufacturing system