检索结果-南通市图书馆

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 {2. engineering,xiamen university,xiamen 361.05,china 2.state key laboratory of {12. Chemistry of solid surfaces,xiamen university,xiamen 361.05,china 1. department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China 2. {1. key {2. of physical Chemistry of solid surfaces Xiamen University Xiamen 361005 China

A constant current electrochemical deposition was employed to incorporate CdS nanoparticles into the TiO{1.nanotube arrays (TiO{1.Ts). The size and amount of CdS nanoparticles in TiO{1.Ts (CdS@TiO{1.Ts) 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 TiO{1.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 TiO{1.Ts was observed and the photocurrent response range was significantly extended into the visible region because of the CdS incorporation. Compared with pure TiO{1.Ts,under a visible light irradiation,CdS@TiO{1.Ts 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

在线全文

学校读者我要写书评

暂无评论

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 {2. engineering, Suzhou university, Suzhou 2.5006, china 2. state key laboratory for physical Chemistry of solid surfaces and department of Chemistry, college of Chemistry and {2. engineering, xiamen university, xiamen 361.05, china 1. department of Chemistry College of Chemistry and Chemical Engineering Suzhou University 215006 Suzhou China 2. {1. key {2. 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.

A simple solvothermal route towards the morphological control of ZnO and tuning of its optical and photocatalytic properties

在线全文

学校读者我要写书评

暂无评论

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 {2. for physical Chemistry of solid surfaces department of Chemistry,college of Chemistry and chemical engineering,xiamen university,xiamen 361.05,china 1. state {1. {2. 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

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

在线全文

学校读者我要写书评

暂无评论

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 {2. of physical Chemistry of solid surfaces,department of Chemistry,college of Chemistry and chemical engineering,xiamen university,xiamen 361.05,china 2.college of Chemistry and chemical engineering,Ocean university of china,Qingdao 2.6100,china 1. state {1. {2. 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

在线全文

学校读者我要写书评

暂无评论

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 {2. of physical Chemistry of solid surfaces department of Chemistry,college of Chemistry and chemical engineering,xiamen university,xiamen 361.05,china 2.chool of Chemistry and Environment,South china Normal university,Guangzhou 510006,china 1. state {1. {2. 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.H2.)2.ClO4)2. (1.,[Cu2.μ-ox)(LRR)2.CH3COCH3)2.ClO4)2.(1.),[Cu2.μ-ox)(LSS)2.H2.)2.ClO4)2. (2. and [Cu2.μ-ox)(LRR)(LSS)2.CH3COCH3)2.ClO4)2. (3) [LRR = (8R,1.R)-(-)-[4,5]-pineno2.2.-bipyridine,LSS = (8S,1.S)-(+)-[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 1. 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

Hydroalumination of diazo and azido compounds:An Al-H addition to end-on nitrogen of substrates

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2010年第9期53卷 1970-1977页

作者： CHU ChenHui1,YANG Ying1,2.& ZHU HongPing1 1state key {2. of physical Chemistry of solid surfaces National engineering {2. for Green chemical Productions of Alcohols-Ethers-Esters college of Chemistry and chemical engineering,{12. university,{12. 361.05,china 2.chool of Chemistry and chemical engineering,Central South university,Changsha 410083,china 1. state {1. {2. of physical Chemistry of solid surfaces National engineering {1. for Green {2. Productions of Alcohols-Ethers-Esters college of Chemistry and {1. {2. Xiamen University Xiamen 361005 China2. School of Chemistry and Chemical Engineering Central South University Changsha 410083 China

This paper reports the reactions of a monomeric aluminum dihydride LAlH2.L = HC[C(Me)N(Ar)]2.Ar = 2.6-i-Pr2.6H3) with diazo,azido,and terminal alkyne *** reaction of LAlH2.with N2.H(SiMe3) and N3(1.Ad) occurred through an Al-H addition to end-on nitrogen to yield respective compounds LAl[N(H)N = CH(SiMe3)]2.1. and LAl[N(H)N=N(1.Ad)]2.2.,while the reaction of LAlH2.with PhC≡CH occurred through a stepwise deprotonation to yield LAlH(C≡CPh)(5) and LAl-(C≡CPh)2.6),respectively.2.further reacted by N2.release to yield LAl[NH(1.Ad)][N(H)N=N(1.Ad)](3) and LAl[NH-(1.Ad)]2.4) upon the increased temperature *** 1.6 have been fully characterized,revealing novel reactivity patterns of LAlH2.toward different substrates under the steric influence from the bulky L ligand at Al.

关键词： hydroalumination bulky aluminum hydride multiple-bond molecule Al–H addition

Synthesis and characterization of stable osmafuran starting from HC≡CCH(OH)C≡CH and OsHCl(CO)(PPh_3)_3

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2010年第9期53卷 1978-1981页

作者： ZHANG Hong,LIN Ran,LUO Ming & XIA HaiPing state key {2. for physical Chemistry of solid surfaces college of Chemistry and chemical engineering,xiamen university,xiamen {12.,china 1. state {1. {2. for physical Chemistry of solid surfaces college of Chemistry and {1. {2. Xiamen University Xiamen 361005 China

This paper presents a new convenient route to prepare osmafuran starting from readily accessible HC≡C CH(OH)C≡CH and OsHCl(CO)(PPh3)*** of a solution of OsHCl(CO)(PPh3)3 in dichloromethane with HC≡C CH(OH)C≡CH,followed by the addition of acetic acid,produced osmafuran [Os(CHC(PPh3)CO(CH2.H3))Cl(CO)(PPh3)2.Cl(2..2.has been isolated in good yield and fully characterized.1. and 1.C NMR spectra show the characteristic downfield chemical shifts of the ring hydrogen and carbon *** and X-ray diffraction data provide strong evidence for the aromatic nature of *** due to the effect of the phosphonium substituent,2.exhibits remarkable thermal stability,air stability and lower reactivity.

关键词： osmafuran metallaaromatics phosphonium salt synthesis stability

An Ab Initio Study of N_2. Decomposition on MgO Catalyst

在线全文

学校读者我要写书评

暂无评论

Chinese chemical Letters 1998年第6期9卷 583-586页

作者： Xin LU Xin XU Nan Qin WANG and Qian Er ZHANG(state {1. {2. for physical Chemistry of solid surfaces, Institute of physical Chemistry,department of Chemistry, xiamen university, xiamen 361.05) xiamen Univ Dept Chem State Key Lab Phys Chem Solid Surfaces Inst Chem Phys Xiamen 361005 Peoples R China

Ab initio calculations based on density functional theory have been used to study thedecompsition of N_2. on MgO. The reaction is predicted to occur on O_3c and O_(4c) atoms, but not onO_(5c) atoms, with an activation barrier of 2.-2. kcal/mol, in agreement with the experimental valueof 35 kcal/mol. Natural bond orbital analysis shows that the reaction leaves O ad-atoms on thosesurface O anions to form a peroxide-like 'O^2.(2.)' species. The )O-O bond stretching frequency ispredicted to be in the range from 82. cm(-1. to 82. cm(-1..

关键词： Ab initio calculation N_2. decomposition MgO catalyst

Size and support effects for CO oxidation on supported Pd catalysts

在线全文

学校读者我要写书评

暂无评论

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 {2. of physical Chemistry of solid surfaces National engineering {2. for Green chemical Productions of Alcohols-Ethers-Esters department of Chemistry,college of Chemistry and chemical engineering,xiamen university,xiamen 361.05,china 1. state {1. {2. 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

Interaction of citrate with Pt(1.0) surface investigated by cyclic voltammetry towards understanding the structure-tuning effect in nanomaterials synthesis

在线全文

学校读者我要写书评

暂无评论

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 {2. 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 {2. 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 {12.

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(1.0) 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(1.0) surface could induce increasing the (1.0) surface domains of two-dimensional long range order ({1.-(1.0)),and decreasing the (1.0) surface domains of one-dimensional short range order (1.-(1.0)).It also revealed that the interaction of citrate with Pt(1.0) surface could stabilize the {1.-(1.0) *** findings gained in this study implied that the citrate may lead to form stable {1.-(1.0) domains on Pt nanoparticles upon the shape-controlled synthesis of Pt nanomaterials.

关键词： citrate interaction Pt(1.0) adsorption