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Interaction of citrate with Pt(100) surface investigated by cyclic voltammetry towards understanding the structure-tuning effect in nanomaterials synthesis

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中国科学:化学 2012年第11期42卷 1653-1654页

作者： CHEN DeHao,YE JinYu,XU ChangDeng,LI Xin,LI JunTao,ZHEN ChunHua,TIAN Na,ZHOU ZhiYou & SUN ShiGang State Key Laboratory of Physical chemistry of Solid Surfaces department of chemistry,college of chemistry and chemical engineering and school of energy research,xiamen university,xiamen 361.05,china State Key Laboratory of Physical chemistry of Solid Surfaces department of chemistry college of chemistry and chemical engineering and school of energy research xiamen university xiamen 361.05 china

This study aims to understand the effects of functional agents such as capping agents,stabilizers,surfactants and additives in shape-controlled synthesis of *** well-defined Pt(100) single crystal surface was used as a model to investigate its interaction with citrate,a capping agent that is often used in shape-controlled synthesis of *** demonstrated that,through a systematic study of electrochemical cyclic voltammetry,the presence of citrate in solution could increase the current peak density of hydrogen adsorption at high potential (j p,L),while decrease proportionally the current peak density of hydrogen adsorption at low potential (j p,S).Furthermore,the increase of citrate concentration shifted negatively the peak potentials (E p,L and E p,S) of both j p,L and j p,*** results indicated that the interaction of citrate with Pt(100) surface could induce increasing the (100) surface domains of two-dimensional long range order (2D-(100)),and decreasing the (100) surface domains of one-dimensional short range order (1D-(100)).It also revealed that the interaction of citrate with Pt(100) surface could stabilize the 2D-(100) *** findings gained in this study implied that the citrate may lead to form stable 2D-(100) domains on Pt nanoparticles upon the shape-controlled synthesis of Pt nanomaterials.

关键词： citrate interaction Pt(100) adsorption

Synthesis,characterization,structures and magnetic property of chiral oxalate-bridged dicopper(Ⅱ) complexes

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Science china chemistry 2010年第6期53卷 1255-1260页

作者： WU Ling1,WANG Jun2,ZHU CaiFei1,LIN YiJi1,CHEN LeiQi1,FAN Jun2 & ZHANG Hui1 1State Key Laboratory of Physical chemistry of Solid Surfaces department of chemistry,college of chemistry and chemical engineering,xiamen university,xiamen 361.05,china 2school of chemistry and Environment,South china Normal university,Guangzhou 510006,china 1. State Key Laboratory of Physical chemistry of Solid Surfaces department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. School of Chemistry and Environment South China Normal University Guangzhou 510006 China

The oxalato-bridged dicopper(II) complexes [Cu2(μ-ox)(LRR)2(H2O)2(ClO4)2] (1),[Cu2(μ-ox)(LRR)2(CH3COCH3)2(ClO4)2](1a),[Cu2(μ-ox)(LSS)2(H2O)2(ClO4)2] (2) and [Cu2(μ-ox)(LRR)(LSS)2(CH3COCH3)2(ClO4)2] (3) [LRR = (8R,10R)-(-)-[4,5]-pineno2,2′-bipyridine,LSS = (8S,10S)-(+)-[4,5]-pineno-2,2′-bipyridine;ox2= oxalate] were first prepared.A possible mechanism for the formation of the chial dicopper(II) complexes was *** on elemental analysis,conductance measurement,UV-Vis spectra,CD spectra and X-ray single-crystal diffraction,the oxalato-bridged structures of 1 and 2 were deduced to adopt two Cu(II) ions and the bridged oxalate lying in the nearly same *** crystal structures of 1a and 3 reveal that the coordination geometry around each Cu(II) ion is an elongated and distorted octahedron and two axial solvent molecules and two perchlorate ions are anti to each other respectively in both binuclear *** solution CD spectra of 1 and 2 in the visible d-d range show very weak Cotton effects with peaks at 588 and 779 nm,which are approximately of mirror image,suggesting the optical activities may be derived from the vicinal effects of the chiragenic centers at the pinene group of LRR and LSS,*** 1 has been characterized by variable-temperature magnetic susceptibility and the data was least-square fitted to the Blenaey-Bowers *** exchange integral J was found to be -338.41(4) cm-1,indicating a strong antiferromagnetic interaction between two copper(II) ions.

关键词： dicopper(II) complex chiral bipyridine μ-oxalate bridge crystal structure CD spectroscopy magnetic property

Evaluation of non-covalent interaction between Seryl-Histidine dipeptide and cyclophilin A using NMR and molecular modeling

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Science china chemistry 2010年第9期53卷 1987-1993页

作者： LIU Yan1,SHI YanHong2,LIU XiaoXia1,LIN MingKun1,LIN DongHai1,2 & ZHAO YuFen1,3 1Key Laboratory for chemical Biology of Fujian Province,department of chemical Biology,department of chemistry,college of chemistry and chemical engineering,xiamen university,xiamen 361.05,china 2Shanghai Institute of Materia Medica,Shanghai Institutes of Biological Sciences,Chinese Academy of Sciences,Shanghai 201203,china 3Key Laboratory for Bioorganic Phosphorus chemistry and chemical Biology,Ministry of Education,department of chemistry,school of Life Sciences and engineering,Tsinghua university,Beijing 100084,china 1. Key Laboratory for chemical Biology of Fujian Province Department of Chemical Biology Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. Shanghai Institute of Materia Medica Shanghai Institutes of Biological Sciences Chinese Academy of Sciences Shanghai 201203 China3. Key Laboratory for Bioorganic Phosphorus Chemistry and Chemical Biology Ministry of Education Department of Chemistry School of Life Sciences and Engineering Tsinghua University Beijing 100084 China

Seryl-Histidine dipeptide(Ser-His) has been previously reported to be capable of cleaving DNAs and carboxyl esters,as well as *** protein cleavage mechanism has not been addressed *** an initial step of protein cleavage activity,the non-covalent binding affinity of Ser-His for proteins is a crucial *** this work,we took cyclophilin A(CyPA) as a substrate protein,and evaluated the non-covalent interaction between CyPA and Ser-His using a combination of NMR spectroscopy and molecular modeling *** independent Ser-His binding sites on CyPA were detected using 15N-1H heteronuclear single-quantum coherence(HSQC) *** binding site binds one Ser-His *** constants,Kd1 and Kd2,were estimated to be 2.07 and 6.66 mmol/L,respectively,indicative of the weak non-covalent interaction between Ser-His and *** on molecular modeling results,we suggest that both the α-amino and the side chain hydroxyl group of Ser-His are crucial for the non-covalent interaction between Ser-His and *** work sheds light on the molecular mechanism of Ser-His and its analogues cleaving proteins.

关键词： Ser-His cyclophilin A HSQC non-covalent interaction binding sites

Preparation of Metal and Metal Oxide Nanocrystals with Exposed High-energy Crystal Facets

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Preparation of Metal and Metal Oxide Nanocrystals with Expos...

Shape-control of Noble-metal and Metal Oxides with High-energy Facets Exposed

中国化学会第六届全国结构化学学术会议

作者： Zhao-Xiong Xie State Key Laboratory for Physical chemistry of Solid Surfaces & department of chemistry, college of chemistry and chemical engineering,xiamen university,xiamen 361.05,china.

＜正＞The physical and chemical properties of nanocrystals depend on the surface *** with high-energy facets exposed usually show high physical and chemical activities,due to abundant unsaturated coordination atoms and atomic steps and ***,in order to minimize the surface energy of the crystals,the high-energy facets quickly disappeared in the crystal growth ***,

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Shape-control of Noble-metal and Metal Oxides with High-ener...

Industrial Loop Reactor for Catalytic Propylene Polymerization:Dynamic Modeling at Emergency Accidents

中国化学会第六届全国结构化学学术会议

作者： Zhao-Xiong Xie~* State Key Laboratory for Physical chemistry of Solid Surfaces & department of chemistry, college of chemistry and chemical engineering,xiamen university,xiamen 361.05,china.

＜正＞The physical and chemical properties of nanomaterials depend on the surface *** with high-energy facets exposed usually show high physical and chemical activities,due to abundant unsaturated coordination atoms and atomic steps and ***,in order to minimize the surface energy of the crystals,the high-energy facets quickly disappeared in the crystal growth ***,

关键词：

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Industrial Loop Reactor for Catalytic Propylene Polymerizati...

Studies on the Performance and Structure of Supported Catalysts for the Partial Oxidation of Methane to Syngas

2010年全国高分子材料科学与工程研讨会

作者： Pei-Lin Su,Zheng-Hong Luo~* (department of chemical and Biochemical engineering,college of chemistry and chemical engineering,xiamen university,xiamen 361.05,P R china

＜正＞In industrial loop reactors for catalytic propylene polymerization,reactor pressure may influence polymerization rate,feed flow and product properties,especially safety operation of the *** order to predict the pressure change during the polymerization and check the performance of pressure relief devices in response to emergency accidents,a dynamic model is developed based on the mass,energy,thermodynamics and kinetics *** this model,the pressure is associated to the temperature by a state-equation for high-pressure *** pipeline equations of the reactors described by the conservation of mechanical energy are incorporated into the model to better predict the *** the pressure,the model can also predict other variables,such as temperature,slurry density,and solid hold-up in the *** data from an industrial plant are used for parameter estimation and model ***,the application of the model is demonstrated by simulating several typical emergency accidents.

关键词： Propylene polymerization Loop reactor Emergency relief Dynamic simulation

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Journal of energy chemistry 2002年第Z2期 159-164页

作者： Tinghua Wu, Mingqiao Zhu, Zhenjiang Niu, Yijun Zhong, Yan Guan, Ya Liu, Qiangu Yan, Zelin Li, Huilin WanZhejiang Normal university, Institute of Physical chemistry, Jinhua 321004, chinaZhejiang university, department of chemical engineering, Hangzhou 310027, chinaxiamen university, department of chemistry, xiamen 361.05, china

The catalytic properties of several supported metal catalysts on different carriers were studied in the partial oxidation of methane (POM) to syngas. In our experiment, supported noble metal catalysts exhibited better performance than the other supported transition metal catalysts. The catalyst performances were significantly influenced by the d-electron configuration of the active metal components and the dispersion of active metal components on the support. A catalyst with a moderate number of unpaired electrons in the d-orbital of the active metal support without obvious acidity or redox activity (e.g. MgO) was suitable for POM performance. The Rh/SiO2 catalyst was the best in the POM reaction, among those investigated. Reaction conditions apparently also affected the POM performance of the catalyst. The conversion of methane and the selectivity for CO increased with the reaction temperature, and a high CH4/O2 ratio was not beneficial for POM performance.

关键词： 

Theoretical Study on the Reaction Mechanism of F2+2HBr = 2HF+Br2

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Chinese Journal of Structural chemistry 2005年第11期 110-115+12页

作者： SUN De-Shenga, b WANG Zun-Yaob YANG Chun-Shengb a (school of chemistry and chemical engineering, Nanjing university of Technology, Jiangsu, Nanjing 210009, china) b(department of chemical engineering, Yancheng Institute of Technology, Jiangsu, Yancheng 224003, china)

The gas phase reaction mechanism of F2 + 2HBr = 2HF + Br2 has been investigated by (U)MP2 at 6-311G** level, and a series of four-center and three-center transition states have been obtained. The reaction mechanism was achieved by comparing the activation energy of seven reaction paths, i.e. the dissociation energy of F2 is less than the activation energy of the bimolecular elementary reaction F2 + HBr → HF + BrF. Thus it is theoretically proved that the title reaction occurs more easily in the free radical reaction with three medium steps.

关键词： (U)MP2 transition state reaction mechanism free radical reaction.

Status of study on biological and toxicological effects of nanoscale materials

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Science china chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High energy Physics, Chi-nese Academy of Sciences, Beijing 100049, china 2. college of chemistry and Molecular engineering, Peking university, Beijing 100871, china 3. department of Occupational and Environmental Health Sciences, school of Public Health, Peking university, Beijing 100083, china 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. college of chemistry and Molecular engineering Peking University 100871 Beijing China 3. department of Occupational and Environmental Health Sciences School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.