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Journal of wuhan university of Technology(Materials science) 2011年第1期26卷 28-32页

作者：宾晓蓓 college of Resources & Environment Engineering Wuhan University of Technology

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 35 nm were tightly encapsulated by the carbon capsules. The detailed formation mechanism for the carbon nanotubes encapsulated nickel nanorods were discussed briefly.

关键词： carbon nanotube nickel nanorod pyrolysis core-shell

Systematic study of the transfer of amino acids across the water/1,2-dichloroethane interface facilitated by dibenzo-18-crown-6

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science china chemistry 2004年第1期47卷 24-33页

作者： CHEN Yong, YUAN Yi, ZHANG Meiqin, LI Fei, SUN Peng, GAO Zhao & SHAO YuanhuaState Key Laboratory of Electroanalytical chemistry, Changchun Institute of Applied chemistry, Chinese Academy of sciences, Changchun 130022, china college of chemistry and molecular Engineering, Peking university, Beijing 100871, china Lab. of Electroanalytical Chem. Changchun Inst. of Appl. Chem. Chinese Acad. of Sci. Changchun 130022 China Coll. of Chem. and molecular Eng. Peking Univ. Beijing 100871 China

Facilitated ion transfer reactions of 20 amino acids with dibenzo-18-crown-6 (DB18C6) at the water/1,2-dichloroethane (W/DCE) interfaces supported at the tips of micro- and nano-pipets were investigated systematically using cyclic voltammetry. It was found that there were only 10 amino acids, that is, Leu, Val, lie, Phe, Trp, Met, Ala, Gly, Cys, Gin (in brief), whose protonated forms as cations can give well-defined facilitated ion transfer voltammograms within the potential window, and the reaction pathway was proven to be consistent with the transfer by interfacial complexation/dissociation (TIC/TID) mechanisms. The association constants of DB 18C6 with different amino acids in the DCE (β0), and the kinetic parameters of reaction were evaluated based on the steady-state voltammetry of micro- or nano-pipets, respectively. The experimental results demonstrated that the selectivity of complexation of protonated amino acid by DB18C6 compared with that of alkali metal cations was low, which can be attributed to the vicinal effect arising from steric hindrance introduced by their side group and the steric bulk effect by lipophilic stabilization. Moreover, the association constants and the standard rate constants for different amino acids showed good correlations with their hydrophobicity (π), except Gly and Met, which inferred that the selectivity of such heterogeneous complex reaction for different amino acids with DB18C6, was not only affected by discrimination in binding these ions to the crown ether macro-cycle, but also significantly modified by the ion transfer Gibbs energy which was closely related to the structure of the transferred ions, protonated amino acids.

关键词： micro-/nano-pipet, water/1,2-dichloroethane interface, facilitated ion transfer, cyclic voltammetry, amino acid.

Chemiluminescence Determination of Tetracycline and Oxytetracycline in Pharmaceutical Preparations Using Ru(bipy)_3^(2+)-Cerium(Ⅳ) System

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wuhan university Journal of Natural sciences 2000年第1期5卷 93-97页

作者： HAN He-you HE Zhi-ke ZENG Yun’e (college of chemistry and Environmental science, wuhan university, wuhan 430072, china) college of chemistry and Environmental science Wuhan University Wuhan 430072 China

A new chemiluminescence (CL) method for the determination of tetracycline and oxytetracycline is developed, hased on the CL reaction of tetracycline and oxytetracycline with Ru(bipy)_3~2+ and Ce(IV). In sulfuric acid medium, the CL emission is generated upon continuous oxidation of Ru(bipy)_3~2+ by cerium (IV ). The emission intensity is greatly enhanced when tetracycline and oxytetracycline are introduced into the reaction system after acid degradation. Under the optimum conditions, the calibration curves are linear over the range of 8. 0 X 10^-8^-4. 0 X 10^-6 mol/L for tetracycline and of 2. 0 X 10^-7~4. 0 X 10^-5 mol/L for oxytetracycline, with the detection limits are 4. 2 X 10^-8 mol/L for tetracycline and 1. 5 X 10^-7 mol/L for oxytetracycline, respectively. The proposed method was used for the determination of tetracycline and oxytetracycline in pharmaceutical formulations with good results.

关键词： chemiluminescence tris (2,2'-bipyridine)ruthenium(II) cerium(Ⅳ) tetracycline oxytetracycline

Synthesis of Novel High Energy Polyaniline Derivative Containing S-S Bond in Six-membered Cycle

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Synthesis of Novel High Energy Polyaniline Derivative Contai...

微量热技术检测古生菌启动子DNA片段的启动功能

第三届全国有机化学学术会议

作者： ZHOU, Lei DENG, Shi-Ren LI, Zao-Ying ( college of chemistry and molecular science, wuhan university, wuhan 430072 )

＜正＞ A novel conducting polymer as new class of high energy storage material, which has one six-membered cycle containing S-S bond in the moiety of aniline was synthesized. The polymer had enhanced redox progress due to an intramolecular electrocatalytic effect of polyaniline on S-S bond. The polymer has some advantages because of its high theoretical specific energy and fast kinetics when used in lithium batteries. The most promised advantage of

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武汉大学学报（理学版） 2003年第4期49卷 509-513页

作者：黄玉屏刘义高振霆沈萍武汉大学生命科学学院湖北武汉430072 武汉大学化学与分子科学学院湖北武汉430072

用微量热法研究了大肠杆菌HB10 1及其重组菌株的代谢特征 .将不同大小的来源于嗜盐古生菌染色体DNA的启动子片段插入启动子探针载体中的氯霉素抗性基因前 ,获得重组菌株 .结果表明重组菌株的半抑制浓度与DNA片段的启动功能大小是一致的 ... 详细信息

用微量热法研究了大肠杆菌HB10 1及其重组菌株的代谢特征 .将不同大小的来源于嗜盐古生菌染色体DNA的启动子片段插入启动子探针载体中的氯霉素抗性基因前 ,获得重组菌株 .结果表明重组菌株的半抑制浓度与DNA片段的启动功能大小是一致的 ,并且质粒的复制几乎不影响菌株的生长及代谢 .培养基中加入氯霉素后 ,启动子启动氯霉素抗性基因表达 ,生长速率 (k)降低 ,最大峰的出现时间 (tp)延长 ,最大峰值 (pm)也随之降低 .在一定范围内 ,抗生素浓度与tp、pm 呈线性关系 .本研究结果直接证明了来自嗜盐古生菌的RM0 7、RM0 8和RM13片段在大肠杆菌中是有启动功能的 ,而且还表明基因表达量的高低与释放的代谢热变化相一致 .

关键词：古生菌启动子 DNA片段启动功能微量热法基因表达代谢热微生物遗传学

Role of inositol 1,4,5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2,3,5) Jian GAO~2 Xiao-mei LAN~3 Gang WANG~4 Sheng WEI~4 Rui-ping XIAO~4 Qi-de HAN~32 Department of Pharmacology,School of Chemical Biology & Pharmaceutical sciences,Capital university of Medical sciences,Beijing 100069,china 3 Institute of Cardiovascular science at Health science Center,Peking university Beijing 100083,china 4 Institute of molecular Medicine and college of Life science,Peking university,Beijing 100871,china Department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing 100069 China Institute of Cardiovascular science at Health science Center Peking University Beijing 100083 China Institute of molecular Medicine and college of Life science Peking University Beijing 100871 China

Aim:Intracellular Ca2+plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4,5-trisphosphate receptors（IP3Rs）in the media-tion of cardiac intracellular Ca2+and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3Rsmay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2+sparkoccurrence and global Ca2+***,we hypothesized that Ca2+releasethrough IP3Rs was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4,5-trisphosphate hexakis（butyryloxymethyl）ester（IP3BM）,a membrane-permeant ester of IP3,to activate IP3Rs directly,and Fluo 4/AM tomeasure intracellular Ca2+***:IP3BM(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2+spark release（especially in the perinuclear area）and global Ca2+*** importantly,IP3R inhibitors,2-aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3BM-induced Ca2+responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3H]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（48 h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3R signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4,5-trisphosphate receptors Ca2+sparks α1 adrenergic stimulation cardiac hypertrophy

The Thermal Decomposition and Kinetics of Dehydration of Copper(Ⅱ) Acetate Monohydrate

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The Thermal Decomposition and Kinetics of Dehydration of Cop...

IMPACT PROPERTIES OF METALLOCENE - CATALYZED ETHYLENE-α-OLEFIN COPOLYMERS

中国化学会2005年中西部十五省（区）、市无机化学化工学术交流会

作者： Keli Zhang, Jianhe Hong, Guihua Cao, Dan Zhan, Youtian Tao, Changjie Cong college of chemistry and molecular science, wuhan university, wuhan 430072, china Centre of Nanoscience and Nanotechnology Research, wuhan university, wuhan 430072, china

The thermal decomposition of copper (Ⅱ) acetate monohydrate was studied in air using TG-DTG/DTA, DSC, XRD techniques. TG-DTA curves show that the decomposition occurs in four steps. TG and XRD data indicate the reduction of Cu (Ⅱ) during the decomposition of CuAc2·H2O. DTG and DSC data imply at least two steps contained in dehydration reaction which is verified by the activation energy values estimated with Friedman and Flynn-Wall-Ozawa (FWO) methods. The most possible kinetic model function has been estimated with multivariate non-linear regression method assuming an A→B→C reaction process. R2→Cn model fits the measurements best. Obtained activation energies and pre-exponential factors are 207.6kJ/mol and 1.8×l025S-1 for R2 step, 79.1kJ/mol and 6.0×l07S-1 for Cn step, respectively.

关键词： copper acetate monohydrate thermal decomposition dehydration kinetics multiple-step reaction multivariate non-linear regression

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Chinese Journal of Polymer science 2002年第5期20卷 473-480页

作者： Xu-rong Xu Jun-ting Xu Lin-xian Feng Department of Polymer science and Engineering Zhejiang university Hangzhou 310027,china Department of Polymer science and Engineering college of chemistry & molecular Engineering Peking university Beijing 100871, china Zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China Peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China

The impact properties of two selected metallocene-catalyzed ethylene-butene copolymers and one conventionalcopolymer were evaluated using Izod impact test. It is found that the metallocene-catalyzed copolymer shows superior impactproperties. This result was explained on the basis of the more homogeneous inter-molecular composition distribution andnarrower molecular weight distribution, which leads to more homogeneous morphology with fewer defects. Stepwisecrystallization improves the impact properties, especially in the crack propagation process, to a large extent. This is due to thedecrease of entanglements by stepwise crystallization, which is advantageous for the chain slip and shear. The polymer withheterogeneous intra-molecular composition distribution exhibits a more evident improvement of impact properties understepwise crystallization.

关键词： Metallocene-catalyzed ethylene-butene copolymer Impact properties molecular heterogeneities Thermal treatment

“LIVING”/CONTROLLED RADICAL POLYMERIZATION OF ETHYL METHYLACRYLATE WITH 2,2’-AZOBISISOBUTYRONITRILE/FERRIC CHLORIDE/TRIPHENYLPHOSPHINE INITIATION SYSTEM

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Chinese Journal of Polymer science 2000年第2期18卷 149-153页

作者： Xiao-ping Chen Kun-yuan Qiu Department of Polymer science and Engineering, college of chemistry, Peking university, Beijing 100871, china Peking Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China

'Living'/controlled radical polymerization of ethyl methacrylate (EMA) was carried out with a 2,2'-azobisisobutyronitrile (AIBN)/ferric chloride (FeCl_3)/triphenylphosphine (PPh_3) initiation system at 85℃. Thc numberaverage molecular weight (M_n) increases linearly with monomer conversion and the rate of polymerization is first order withrespect to monomer concentration. The M_w of PEMA ranges from 3900 to 17600 and the polydispersity indices are quitenarrow (1.09～1.22). The conversion can reach up to～100% and M_w of the polymers obtained is close to that designed. Thepolymerization mechanism belongs to the reverse atom transfer radical polymerization (ATRP). The polymer was end-functionalized by chlorine atom, which acts as a macroinitiator to proceed extension polymerization in the presence ofCuBr/bipy catalyst system via an ATRP process. The presence of ω-chlorine in the PEMA obtained was identified by ~1H-NMR spectrum.

关键词： 'Living'/controlled radical polymerization Reverse ATRP Ethyl methacrylate AIBN/FeCl_3/PPh_3 Bulk polymerization