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Science china chemistry 2010年第8期53卷 1711-1717页

作者： JIANG YaQi,LI FangFang,SUN Ran,XIE ZhaoXiong & ZHENG LanSun State Key Laboratory for Physical chemistry of Solid Surfaces department of chemistry,college of chemistry and chemical engineering,xiamen university,xiamen 361005,china 1. State Key Laboratory for Physical chemistry of Solid Surfaces department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

ZnO nanoparticles with different morphologies were solvothermally synthesized by controlling the alkali (sodium hydroxide) concentration in an isopropanol *** products were characterized by means of powder X-ray diffraction,UV-visible absorption spectra,scanning electron microscopy,transmission electron microscopy,and selected area electron *** morphologies of the formed ZnO nanocrystals were dependent on the concentration of the alkali,and with increases of sodium hydroxide concentration,the ZnO nanocrystals evolved from rod to hexagonal bipyramid,and then to a flower-like *** flower-like nanostructure resulted from the etching of the hexagonal bipyramid by the excess *** photoluminescence and photocatalytic properties of the prepared ZnO were *** difference of green emission among the ZnO nanocrystals indicated that a higher sodium hydroxide concentration led to a higher level of *** size,the surface structure and defects in the ZnO nanocrystals affected its photo-degradation characteristics.

关键词： zinc oxide solvothermal method nanocrystal photoluminescence photocatalysis

Controllable incorporation of CdS nanoparticles into TiO_2 nanotubes for highly enhancing the photocatalytic response to visible light

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Science china chemistry 2009年第12期52卷 2148-2155页

作者： WANG ChengLin1,SUN Lan1,XIE KunPeng1 & LIN ChangJian1,2 1 department of chemistry,college of chemistry and chemical engineering,xiamen university,xiamen 361005,china 2 State Key Laboratory of Physical chemistry of Solid Surfaces,xiamen university,xiamen 361005,china 1. department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China 2. State Key Laboratory of Physical chemistry of Solid Surfaces Xiamen University Xiamen 361005 China

A constant current electrochemical deposition was employed to incorporate CdS nanoparticles into the TiO2 nanotube arrays (TiO2NTs). The size and amount of CdS nanoparticles in TiO2NTs (CdS@TiO2NTs) were controllable via modulating current,deposition time and electrolyte concentration. It was revealed,from the scanning electron microscopy (SEM) images and X-ray photoelectron spectroscopy (XPS) in depth profile,that CdS nanoparticles were filled into TiO2 nanotubes. A shift of the absorption edge toward the visible region under the optimal electrodeposition condition was observed with the diffuse reflectance spectroscopy (DRS). A 5-fold enhancement in the photocurrent spectrum for TiO2NTs was observed and the photocurrent response range was significantly extended into the visible region because of the CdS incorporation. Compared with pure TiO2NTs,under a visible light irradiation,CdS@TiO2NTs exhibited a 3.5-fold improvement of photocatalytic activity,which was demonstrated by the photocatalytic decomposition of Rhodamine B (RhB).

关键词： TiO2 nanotube CdS photocatalysis RhB

Adsorption and corrosion inhibition behavior of imidazole on cobalt electrodes studied by SERS and electrochemical methods

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Science china chemistry 2005年第6期48卷 497-503页

作者： GU Wei1, LIU Guokun2, REN Bin2, WU Deyin2, GU Renao1 & TIAN Zhongqun2 1. department of chemistry, college of chemistry and chemical engineering, Suzhou university, Suzhou 215006, china 2. State Key Laboratory for Physical chemistry of Solid Surfaces and department of chemistry, college of chemistry and chemical engineering, xiamen university, xiamen 361005, china 1. department of chemistry College of Chemistry and Chemical Engineering Suzhou University 215006 Suzhou China 2. State Key Laboratory for Physical chemistry of Solid Surfaces and department of chemistry College of Chemistry and Chemical Engineering Xiamen University 361005 Xiamen China

The interaction of imidazole with Co electrodes in an electrochemical system was studied by surface-enhanced Raman scattering (SERS) and electrochemical methods. The SER spectra of Co in an imidazole solution as a function of the applied potential were analyzed and the assignment of the Raman bands was made. It was found that there were three kinds of sur-face species on the Co surface in different potential regions and they were interchangeable de-pending on the potential. In a relatively negative potential region (?1.2 to ?0.9 V), imidazole was adsorbed on the surface and its orientation might change from a vertical configuration via the N-end of the pyridine ring to a tilted configuration via the C2=N3 double bond. In a more positive potential region (?0.8 to ?0.7 V), the SERS signal from the adsorbed imidazole weakened and finally disappeared, meanwhile the signal from the Co and imidazole complex strengthened gradually. At the open circuit potential (?0.6 V), we detected very strong bands from the Co ox-ides. By comparing the Tafel curves of the Co electrode in the solution without and with imidazole, we found that imidazole has a marked effect on the corrosion inhibition of the Co electrode. This result demonstrates that we may be able to reveal the complicated interaction of surface species with metal surface at the molecular level by combining the SERS and electrochemical methods.

关键词： cobalt, imidazole, inhibition, surface-enhanced Raman spectroscopy, Tafel plot.

Size and support effects for CO oxidation on supported Pd catalysts

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Science china chemistry 2010年第9期53卷 2047-2056页

作者： WANG ZhaoWen,LI Bin,CHEN MingShu,WENG WeiZheng & WAN HuiLin State Key Laboratory of Physical chemistry of Solid Surfaces National engineering Laboratory for Green chemical Productions of Alcohols-Ethers-Esters department of chemistry,college of chemistry and chemical engineering,xiamen university,xiamen 361005,china 1. State Key Laboratory of Physical chemistry of Solid Surfaces Xiamen University Xiamen 361005 China2. National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters Xiamen University Xiamen 361005 China3. Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

Supporting Pd catalysts characterized significant different size distribution were obtained using PdCl2,[Pd(NH3)4](NO3)2 and Pd(acac)2 as ***-resolution transmission electron microscopy(TEM),X-ray diffraction(XRD),in-situ Fourier transform infrared spectroscopy(FTIR) and Raman spectroscopy were used to examine the dispersion of *** performance measurements show that the activities for CO oxidation increase as the Pd particle size decreases and the O2/CO ratio *** activities under oxygen rich conditions are significantly higher than those at near the stoichiometric *** on TiO2 prepared by the Pd(acac)2 precursor is highly dispersed,leading to a considerable activity for CO oxidation at near room *** oxidation on the 1 wt% Pd/TiO2 and under an O2/CO ratio of 1 characterized an apparent activation energy of 36.7 kJ/mol,which is closed to those reported for CO oxidation on the supported Au *** present work demonstrates a high catalytic activity of highly dispersed noble metals,and suggests a promising approach of using noble metals as catalysts with exceeding high efficiency.

关键词： noble metals supported palladium CO oxidation size effect support effect

Study on interaction between macrocell and microcell in the early corrosion process of reinforcing steel in concrete

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Science china(Technological Sciences) 2010年第5期53卷 1285-1289页

作者： LI LanQiang1,DONG ShiGang1,WANG Wei2,HU RongGang1,DU RongGui1,LIN ChangJian1,ZHUO XiangDong1 & WANG Jia2 1 State Key Laboratory of Physical chemistry of Solid Surfaces,department of chemistry,college of chemistry and chemical engineering,xiamen university,xiamen 361005,china 2 college of chemistry and chemical engineering,Ocean university of china,Qingdao 266100,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. College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

An array electrode technique was developed as a novel electrochemical method for studying the interaction between macrocell and microcell in the early corrosion process of reinforcing steel in cement *** corrosion potential and galvanic current of macrocell corrosion of the reinforcing steel in cement mortar were imaged by the array electrode technique during the corrosion initiation and *** was certified that the corrosion macrocell current is closely related with the difference of corrosion potential between the anodic and cathodic *** corrosion macrocell and microcell always exist during the corrosion *** interaction of corrosion macrocell and corrosion microcell of steel in concrete was directly sensed by the array electrode for the first time,and was discussed in terms of corrosion electrochemistry.

关键词： reinforcing steel in concrete array electrode macrocell microcell

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 361005,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

Concise synthesis of two advanced intermediates for the asymmetric synthesis of polyhydroxylated indolizidine alkaloids

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Science china chemistry 2010年第9期53卷 1914-1920页

作者： ZHENG Xiao1,2,ZHU WenFang1 & HUANG PeiQiang1 1department of chemistry,college of chemistry and chemical engineering,xiamen university,xiamen 361005,china 2Key Laboratory of Synthetic chemistry of Natural Substances Shanghai Institute of Organic chemistry,Chinese Academy of Sciences,Shanghai 200032,china 1. department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. Key Laboratory of Synthetic Chemistry of Natural Substances Shanghai Institute of Organic chemistry Chinese Academy of Sciences Shanghai 200032 China

A concise five-step approach to indolizidinones 10 and 11,two advanced intermediates for the asymmetric synthesis of polyhydroxylated indolizidine alkaloids,has been developed by using N-Cbz pyrrolidin-2-yl pyridin-2-yl sulfide 13 as the chiral building *** method features a SmI2-mediated coupling of sulfide 13 with functionalized aldehyde 14 and a tandem N-deprotection-lactamization,which constitutes a stepwise "2 + 4" annulation method for the construction of the indolizidinone ring system of 12a.

关键词： indolizidinone samarium diiodide α-amidohydroxyalkylation tandem reaction chiral building block

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 361005,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

Construction of High-Nuclearity 3d-4f Metal Clusters through Incorporation of Anions

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Construction of High-Nuclearity 3d-4f Metal Clusters through...

Construction of High-nuclearity 3d-4f metal clusters via anion-template from in situ decomposition of organic ligand

中国化学会第六届全国结构化学学术会议

作者： La-Sheng Long State Key Laboratory of Physical chemistry of Solid Surface and department of chemistry, college of chemistry and chemical engineering,xiamen university,xiamen 361005,china

＜正＞High-nuclearity metal clusters that show fascinating structures and interesting properties have been attracted much attention in the field of physics,chemistry,biology,nanotechnogly and material science. Of part...

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Construction of High-nuclearity 3d-4f metal clusters via ani...