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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 {1.,College of {1. and Chemical Engineering,Xiamen University,Xiamen 361.05,China 2 State Key Laboratory of Physical {1. of Solid Surfaces,Xiamen University,Xiamen 361.05,China 1. department of {1. 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

Structures and properties of novel 5,1.-di[4-(5-acetylsulfanylpentyloxy)phenyl] porphyrin derivatives:Density functional theory calculations

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Science China chemistry 2010年第10期53卷 2183-2192页

作者： ZHU YiFei1.2, QI DongDong1. ZHANG LiJuan1. WAN Liang1. ZHANG YueXing1.& JIANG JianZhuang1.1.0} of {1., University of Science and Technology Beijing, Beijing 1.0083, China 2department of {1., Hebei North University, Zhangjiakou 075000, China 1. department of {1. University of Science and Technology Beijing Beijing 100083 China2. Department of Chemistry Hebei North University Zhangjiakou 075000 China

Density functional theory (DFT) calculations have been carried out in order to compare the molecular structures, atomic charges, molecular orbitals, electronic absorption spectra, and infrared (IR) spectra of the metal-free 5,1. -di[4-(5-acetylsul-fanylpentyloxy)phenyl]porphyrin H2[DPP(OC5H1.SCOCH3)2] (1. (DPP = 5,1.-diphenylporphyrin) and its zinc complex Zn[DPP(OC5H1.SCOCH3)2] (2), which exhibit novel structures with two 5-acetylsulfanylpentyloxy side chains at the para-positions of opposite meso-attached phenyl groups. The calculated molecular structure and electronic absorption and IR spectra of 1.and 2 are consistent with the experimental results. The influences of meso-substitution, polar solvents, and central metal substitution on the structure and properties of porphyrin derivatives have been investigated by comparing the corresponding data for 1.and 2 with the help of data for the unsubstituted porphyrin derivatives, namely the metal-free porphyrin H2Por (3) and the porphyrinato-zinc compound (4). The identities of the main transitions in the electronic absorption spectra of 1.and 2 are assigned and the vibrational modes in their IR spectra are identified with the assistance of animated pictures produced based on normal coordinates. The theoretical work presented here will be helpful in increasing our understanding of the structure and spectroscopic properties, as well as substituent and solvent effects, for these novel porphyrin compounds.

关键词： porphyrin substituent effect electronic absorption spectra IR spectra density functional theory (DFT)

Local electronic structure and magnetic properties of 3d transition metal doped GaAs

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Science China(Physics,Mechanics & Astronomy) 2008年第5期51卷 470-480页

作者： LIN He1.& DUAN HaiMing21.department of {1.,Institute of Applied {1.,Xinjiang University,Urumqi 830046,China 2department of Physics,Xinjiang University,Urumqi 830046,China 1. department of {1. Institute of Applied Chemistry Xinjiang University Urumqi 830046 China 2. department of Physics Xinjiang University Urumqi 830046 China

The local electronic structure and magnetic properties of GaAs doped with 3d transition metal (Sc, Ti, V, Cr, Mn, Fe, Co, Ni) were studied by using discrete variational method (DVM) based on density functional theory. The calculated result indicated that the magnetic moment of transition metal increases first and then decreases, and reaches the maximum value when Mn is doped into GaAs. In the case of Mn concentration of 1.4%, the magnetic moment of Mn is in good agreement with the experimental result. The coupling between impure atoms in the system with two impure atoms was found to have obvious variation. For different transition metal, the coupling between the impure atom and the nearest neighbor As also has different variation.

关键词： diluted magnetic semiconductor density functional theory 3d transition metal cluster model electronic structure

Assessment of candidate plant DNA barcodes using the Rutaceae family

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Science China(Life Sciences) 2010年第6期53卷 701-708页

作者： LUO Kun1.2,CHEN ShiLin1.CHEN KeLi2,SONG JingYuan1.YAO Hui1.MA XinYe1.ZHU YingJie3,PANG XiaoHui1.YU Hua1.LI XiWen1.4 & LIU Zhen2 1.nstitute of Medicinal Plant Development,Peking Union Medical College,Chinese Academy of Medical Sciences,Beijing 1.01.3,China 2College of Pharmacy,Hubei University of Chinese Medicine,Wuhan 430061.China 3School of Bioscience and Engineering,Southwest Jiaotong University,Chengdu 61.031.China 4department of chemistry,Tsinghua University,Beijing 1.0084,China 1. Institute of Medicinal Plant Development Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100193 China2. College of Pharmacy Hubei University of Chinese Medicine Wuhan 430061 China3. School of Bioscience and Engineering Southwest Jiaotong University Chengdu 610031 China4. Department of Chemistry Tsinghua University Beijing 100084 China

DNA barcoding is a rapidly developing frontier technology that is gaining worldwide ***,seven regions (psbA-trnH,matK,ycf5,rpoC1.rbcL,ITS2,and ITS) with potential for use as DNA barcodes were tested for their ability to identify 300 samples of 1.2 species from 72 genera of the family *** evaluate each barcode’s utility for species authentication,PCR amplification efficiency,genetic divergence,and barcoding gaps were *** found that the ITS2 region exhibited the highest inter-specific divergence,and that this was significantly higher than the intra-specific variation in the "DNA barcoding gap" assessment and Wilcoxon two-sample *** ITS2 locus had the highest identification efficiency among all tested *** a previous study,we found that ITS2 was able to discriminate a wide range of plant taxa,and here we confirmed that ITS2 was also able to discriminate a number of closely related ***,we propose that ITS2 is a promising candidate barcode for plant species identification.

关键词： DNA barcoding ITS2 Rutaceae identification

Potential control of horseradish peroxidase immobilization on gold electrode

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中国科学：化学英文版 2004年第2期47卷 134-141页

作者： GE Cunwang1.2, YU Wei1. LI Changan1. WANG Nanping2 & GU Ning1.1. Key Laboratory of Molecular and Biomolecular Electronics (Southeast University), Ministry of Education, Research Center for Nano-scale Science and Technology, Southeast University, Nanjing 21.096, China 2. department of {1., Nantong Teachers College, Nantong 226007, China 1. Key Laboratory of Molecular and Biomolecular Electronics (Southeast University) Ministry of Education Research Center for Nano-scale Science and Technology Southeast University 210096 Nanjing China 2. department of {1. Nantong Teachers College 226007 Nantong China

A new approach based on potential control was firstly used for the immobilization of horseradish peroxidase (HRP) as the model protein. The self-assembly monolayer (SAM) was prepared with 2-aminoethanethiol (AET) on the gold electrode. The charge on HRP was adjusted by means of the acidity of the phosphate buffer solution (PBS) for dissolving the HRP. The in-fluence of electric potential on HRP immobilization was investigated by means of colorimetric immunoassay of enzyme-substrate interaction (CIESI) using an automatic plate reader. The HRP modified electrodes were characterized with X-ray photoelectron spectroscopy (XPS) as well as atomic force microscope (AFM) on template-stripped gold surface. The potential for maximum immobilization of HRP was near the zero charge potential. The result indicates that controlled potential can affect the course of HRP immobilization without the loss of enzymic activity. It is of great significance for the control of biomolecular self-assembly and the intrinsic electric device.

关键词： electric potential control, horseradish peroxidase, immobilization, gold electrode, self-assembly.

ADSORPTION OF GALLIUM WITH N_503LEVEXTREL RESIN

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中国有色金属学会会刊：英文版 1994年第3期4卷 36-40页

作者： Chen, Jianrong Hu, Jianhua Peng, Chaoqun(department of {1.,Zhe jiang Normal University,Jinhua 321.0 4)

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ＡＤＳＯＲＰＴＩＯＮＯＦＧＡＬＬＩＵＭＷＩＴＨＮ＿５０３ＬＥＶＥＸＴＲＥＬＲＥＳＩＮＣｈｅｎ，Ｊｉａｎｒｏｎｇ；Ｈｕ，Ｊｉａｎｈｕａ；Ｐｅｎｇ，Ｃｈａｏｑｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＺｈｅｊｉａｎｇＮｏｒｍａｌＵｎｉｖｅｒｓｉｔ...

关键词： gallium adsorption N503 levextrel resin

Regioselective aminohalogenation of β-nitrostyrenes using NCS and NBS as nitrogen/halogen sources

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Science China chemistry 2010年第1期53卷 140-146页

作者： ZHI SanJun1.2,SUN Hao2,LIN Chen2,ZHANG GuangQian2,LI GuiGen4 & PAN Yi2,3 1.department of {1.,Huaiyin Normal University,Huai’an 221.03,China 2 School of {1. and Chemical Engineering,Nanjing University,Nanjing 21.093,China 3 State Key Lab of Coordination {1.,Nanjing University,Nanjing 21.093,China 4 department of {1. and Bio{1.,Texas Tech University,Lubbock,Texas 79409-1.61.USA 1. department of {1. Huaiyin Normal University Huai’an 221003 China2. School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China4. Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas 79409-1061 USA3. State Key Lab of Coordination Chemistry Nanjing University Nanjing 210093 China

Aminohalogenation reaction of β-nitrostyrenes with N-halosuccinimides(N-chloro and N-bromosuccinimides) has been successfully conducted by using nickel acetate as a catalyst in the presence of potassium carbonate and succinimide as *** reaction was easily performed at room temperature under nitrogen gas protection to give dihalorinaed haloamino products in good to excellent yields(60%-98%).The structure has been confirmed by X-ray crystal structure analysis.

关键词： aminohalogenation vicinal haloamines β-nitrostyrenes NBS NCS

Stochastic resonance in surface catalytic oxidation of carbon monoxide induced by colored noise

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Science China chemistry 2004年第2期47卷 106-112页

作者： GONG Yubing1.2, HOU Zhonghuai1.& XIN Houwen1.1. department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China 2. department of Physics, Yantai Teachers University, Yantai 264025, China 1. department of Chemical Physics University of Science and Technology of China 230026 Hefei China 2. department of Physics Yantai Teachers University 264025 Yantai China

The dynamical behavior of surface catalytic oxidation reaction of Pt(1.0)/CO+O2 modulated by colored noise, under the condition of specific temperature, has been investigated when the partial pressure of CO gas is near the supercritical Hopf bifurcation point. By computer simulation the oscillation and stochastic resonance induced by colored noise are observed. The influences of the intensity and correlation time of colored noise on stochastic resonance are discussed. The range of sensitivity of the system to the environmental fluctuation is analyzed.

关键词： colored noise, stochastic resonance, surface catalytic reaction of Pt(1.0)/CO+O2, supercritical Hopf bifurcation, signal-to-noise ratio (SNR).

Internal noise stochastic resonance in CO oxidation on nm-sized palladium particles

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Science China chemistry 2005年第5期48卷 395-401页

Based on a stochastic mesoscopic model, the influence of internal noise on the oscillatory kinetics of the catalytic oxidation of CO on nm-sized palladium particles is studied, using the chemical Langevin equations, Poisson approximation algorithm, and exact stochastic simulation algorithm. The reaction rate oscillations are of stochastic nature due to considerable internal noise in such mesoscopic systems. It is found that the performance of the stochastic oscillations undergoes a maximum with the variation of internal noise level for a given CO partial pressure, which demonstrates the occurrence of internal noise stochastic resonance. This phe-nomenon implies that optimal internal noise would favor the reaction rate oscillation of CO oxi-dation on nm particles. Such a phenomenon is robust to the change of external parameters, such as CO pressures.

关键词： nanometer-sized palladium particles, surface catalytic CO oxidation, internal noise, stochastic resonance, chemical Langevin equation.

Degradation of nitrobenzene in wastewater by γ-ray irradiation

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Journal of Environmental Sciences 2004年第3期16卷 364-366页

作者： ZHANG Shu juan 1. FENG Shao hong 1. YU Han qing 1.* , LI Qian rong 2 (1. department of {1., University of Science & Technology of China, Hefei 230026, China. 2 Research Center for Physics & {1., University of Science & Technology of China, Hefei 230026, China) department of {1. University of Science & Technology of China Hefei 230026 China.

The degradation of nitrobenzene(NB) by γ ray irradiation was studied. The influences of dose rate and initial NB concentration were investigated in details. At a dose rate of 55 Gy/min, the degradation kinetics was pseudo first order at NB concentrations from 0 2 mmol/L to 4 0 mmol/L. At an initial NB concentration of 0 8 mmol/L, the degradation of NB at various dose rates also followed pseudo first order kinetics. Dissolved oxygen was found to have a positive effect on NB degradation. The degradation products were identified as nitrophenol, nitrosobenzene, and hydroquinone, and so on. Based on the product analysis, possible degradation pathways of nitrobenzene were proposed.

关键词： degradation irradiation nitrobenzene(NB) kinetics