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Preparation of Core-shell Cu-Ag Bimetallic Powder via Electroless Coating

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Journal of Wuhan university of Technology(Materials Science) 2009年第4期24卷 637-639页

作者：徐锐 College of Metallurgy Science and engineering Central South University College of chemical and Pharmaceutical engineering Henan Universityof Science and Technology

A novel method of electroless silver coating on copper powders was reported, in which hydrazine was used as the reducing agent, and had some advantages such was used as inhibiting the substitution reaction and reducing consumption of copper powders. In the processes of sensitization and activation, AgNO3 replaces the conventional PdCl2. which solves the impurity of bath. Oxide film on the surface of copper powders was tested by chemical analysis. Ag element tested by XRD and XRF is in the form of Ago and exists on the surface of copper powders, which acts as catalyzer in reduction reaction. Morphology and composition of the coating were characterized by SEM and XRD respectively.

关键词： core-shell bimetallic powders electroless coating

Adsorption and Desorption of Thiophene Vapor on NaY/NiY Zeolites

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china Petroleum Processing & Petrochemical Technology 2010年第2期12卷 45-50页

作者： Liu Daosheng~(1,2. Song Lijuan~2.Ju Xiufang~2.Duan Linhai~2.Sun Zhaolin~(1,2. (1.College of chemistry & chemical {2.,china university of Petroleum(East china),Dongying 2.7061 2.Liaoning Key Laboratory of Petrochemical {2.,Liaoning Shihua university) china Univ Petr E china Coll Chem & Chem Engn Dongying 257061 Peoples R China Liaoning Shihua Univ Liaoning Key Lab Petrochem Engn Liaoning Peoples R China

FT-IR spectrometry, TPD and adsorption isotherms of thiophene on NaY/NiY zeolites were carried out and the diffusion coefficient was obtained by means of its real-time dynamic curves. The loading of thiophene adsorbed on the NaY zeolite decreased with an increasing temperature, which was ascribed to the patterns of physical adsorption. Both physical and chemical adsorption phenomena were detected on the NiY zeolite, with the 0 complexation and S-M interaction existing during the chemical adsorption. The loading of thiophene adsorbed on the NiY zeolite at 302.K and 335 K was equal, but it decreased at 373 K. The diffusion coefficient of thiophene on the NaY zeolite decreased when the loading increased to more than 0.02.mmol/g, and on the contrary that of thiophene on the NiY zeolite did not change obviously with the loading adsorbed.

关键词： adsorption diffusion coefficient temperature-programmed desorption (TPD)

In Situ Acquisition of Equivalent Circuit Parameters of Crystal Resonance during Copper Deposition and Dissolution in Acidic Solution by Electrochemical Quartz Crystal Impedance System

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Chinese chemical Letters 1999年第1期10卷 73-76页

作者： Qing Ji XIE Xiao Lian SUN Xiao Lan GU Hong Wei LIU You Yu ZHANG Shou Zhuo YAO(chemical Research Institute. hunan Normal {2.,changsha 410081)(chemistry Department,hunan Normal {2., changsha 410081) hunan Normal Univ Chem Res Inst Changsha 410081 Peoples R China hunan Normal Univ Dept Chem Changsha 410081 Peoples R China

Electrochemical quartz crystal impedance system (EQCIS) which allows in situ dynamic quartz crystal impedance measurement in an electrochemical experiment was developed by combining an HP 4395A Network/Spectrum/Impedance analyzer with an EG&G M2.3 potentiostat. Equivalent circuit parameters of crystal resonance change significantly during electrodeposition and dissolution of copper in 0.1 mol/L H2.O4 aqueous solution in a cyclic potential sweep experiment, which is explained with an overall picture of mass loading, solution density and viscosity, etc..

关键词： in situ quartz crystal impedance measurement equivalent circuit parameters electrodeposition copper

Polyaniline Formed in Alkaline Solution─A New Luminous Material

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Chinese chemical Letters 2000年第8期11卷 681-684页

作者： Nian Bing LI (College of chemistry and chemical {2., Southwest china Normal university, Chongqing 400715) Sheng Tao ZHANG, Pei Dao DING (College of chemistry and chemical {2., Chongqing university, Chongqing 400044) SW china Normal Univ Coll Chem & Chem Engn Chongqing 400715 Peoples R China Chongqing Univ Coll Chem & Chem Engn Chongqing 400044 Peoples R China

Electropolymerization of aniline in KOH solution and properties of the polymer are studied by using in situ reflex ellipsometry, cyclic voltammetry and fluorescence spectroscopic method. The change patterns of ellipsometric parameters and the thickness of film in the process of electropolymerization are investigated. The complex refractive indices and the fluorescence spectra of PAN indicate that the PAN is a new kind of luminous material.

关键词： Polyaniline electropolymerization alkaline solution luminous material.

AlkB recognition of a bulky DNA base adduct stabilized by chemical cross-linking

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Science china chemistry 2010年第1期53卷 86-90页

作者： YI ChengQi1 & HE Chuan1,2.1Department of chemistry,university of Chicago,Chicago,Illinois 60637,USA 2.epartment of {2. Biology,College of chemistry and Molecular engineering,Peking university,Beijing 100871,china 1. Department of chemistry University of Chicago Chicago Illinois 60637 USA2. Department of Chemical Biology College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

*** AlkB is a direct DNA/RNA repair protein that oxidatively reverses N1 alkylated purines and N3 alkylated pyrimidines to regular *** crystal structures have revealed N1-methyl adenine(1-meA) recognition by AlkB and a unique base flipping mechanism,but how the AlkB active site can accommodate bulky base adducts is largely *** a previously developed chemical cross-linking technique,we crystallized AlkB with a duplex DNA containing a caged thymine base(cagedT).The structure revealed a flexible hairpin lid and a reorganized substrate recognition loop used by AlkB to accommodate *** observations demonstrate,at the molecular level,how bulky DNA adducts may be recognized and processed by AlkB.

关键词： DNA/RNA repair AlkB caged thymine disulfide cross-linking bulky base adduct

Biological exposure models for oil spill impact analysis

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Journal of Environmental Sciences 2000年第4期12卷 482-485页

作者： XIONG De qi 1, Mark Reed 2. Narve Ekrol 2.(1. Department of Marine Environmental engineering, Dalian Maritime university, Dalian 11602., {2. E mail: deqi@*** 2. Department of Environmental engineering, SINTEF Applied chemistry Institut 大连海事大学辽宁大连 1 1 6 0 2 SINTEF Applied chemistry Institute 挪威 Trondheim 70 3 4

The oil spill impact analysis (OSIA) software system has been developed to supply a tool for comprehensive, quantitative environmental impact assessments resulting from oil spills. In the system, a biological component evaluates potential effects on exposed organisms based on results from a physico chemical fates component, including the extent and characteristics of the surface slick, and dissolved and total concentrations of hydrocarbons in the water column. The component includes a particle based exposure model for migratory adult fish populations, a particle based exposure model for spawning planktonic organisms (eggs and larvae), and an exposure model for wildlife species (sea birds or marine mammals). The exposure model for migratory adult fish populations simulates the migration behaviors of fish populations migrating to or staying in their feeding areas, over wintering areas or spawning areas, and determines the acute effects (mortality) and chronic accumulation (body burdens) from the dissolved contaminant. The exposure model for spawning planktonic organisms simulates the release of eggs and larvae, also as particles, from specific spawning areas during the spawning period, and determines their potential exposure to contaminants in the water or sediment. The exposure model for wild species calculates the exposure to surface oil of wildlife (bird and marine mammal) categories inhabiting the contaminated area. Compared with the earlier models in which all kinds of organisms are assumed evenly and randomly distributed, the updated biological exposure models can more realistically estimate potential effects on marine ecological system from oil spill pollution events.

关键词： oil spill biological exposure acute effects chronic accumulation migration of fish spawning of eggs and larvae habitat

The study of adsorption gas sensor based carbon nanotube film

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Science china(Technological Sciences) 2005年第4期48卷 372-384页

作者： LI Xin1, LIU Junhua2.& ZHU Changchun1 1. School of Electronic and Information engineering, Xi’an Jiaotong university, Xi’an 710049, {2. 2. School of Electric engineering, Xi’an Jiaotong university, Xi’an 710049, {2. 1. School of Electronic and Information engineering Xi’an Jiaotong University 710049 Xi’an China 2. School of Electric engineering Xi’an Jiaotong University 710049 Xi’an China

The study of gas sensitivity of multi-wall carbon nanotubes (MWNTs), which is deposited by low press chemical vapor deposition (LPCVD), is presented. The results show that the pure MWNTs are not sensitive to the gases measured, while the composite film consisting of the MWNTs and silicon dioxide is sensitive to the methane, the hydrogen and the acetylene. The MWNTs and silicon dioxide composite film have the capacitance characteristic because of the formation of Schottky junctions within the MWNTs. The chemistry adsorption of the gas measured on the surface of the MWNTs affects the space discharge area of the Schottky junction, so that the dielectric constant changes with the gas concentration. That is why the gas is sensed.

关键词： gas sensor, carbon nanotubes, low press chemical vapor deposition, scatter.

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 {2. 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 (TiO2.Ts). The size and amount of CdS nanoparticles in TiO2.Ts (CdS@TiO2.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 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 TiO2.Ts was observed and the photocurrent response range was significantly extended into the visible region because of the CdS incorporation. Compared with pure TiO2.Ts,under a visible light irradiation,CdS@TiO2.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

Biological decomposition of Na_2._2._3 into sulfur by a newly isolated facultative thermophilic alkaline desulphuricant strain

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Science china chemistry 2009年第2期52卷 226-230页

作者： ZHANG JianBin1,ZHANG Tong2.MA Kai2.ZHANG PengYan2.LI Qiang2.& WEI XiongHui1 1 Department of Applied chemistry,College of chemistry & Molecular {2.,Peking university,Beijing 100190,china 2.College of chemical {2.,Inner Mongolia university of Technology,Huhhot 010051,china 1. Department of Applied chemistry College of Chemistry & Molecular Engineering Peking University Beijing 100190 China 2. College of chemical engineering Inner Mongolia University of Technology Huhhot 010051 China

A facultative thermophilic alkaline desulphuricant strain named GDJ-3 was isolated from neutral soils,enriched on sulfur synthetic medium,and detected in previous *** and chemotax-onomic analyses and 16s RNA gene sequencing showed that the strain was in good agreement with Alpha proteobacterium sp.(97%) and ochrobactrum sp.(98%).The regenerative processes of the solu-tion containing sulfur compounds(SCS) from the strain through an orthogonal test were investigated to get the optimum regenerative *** results showed that regenerative temperature,air flow,and stirring speed of the agitator were the main three variables influencing the regenerative processes of the *** optimum regenerative efficiency of the SCS from the strain was obtained when tem-perature,air flow,and stirring speed of the agitator were 318.2.K,3.0 L/min,and zero r/min,*** this condition,when the cell concentration of the strain was adjusted to 107/mL,the concentra-tions of Na2.2.3 and Na2. in the SCS decreased from 112.68 g/L to 96.88 g/L and from 0.87 g/L to 0.11 g/L in 9.5 ***,XRD spectrum shows that sulfur was formed in the regeneration *** results suggest that the strain has potential application to the regeneration of the industrial so-lution containing sulfur compounds.

关键词： bio-desulfurization thermophiles optimization biocomposition orthogonal test