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Potential energy surfaces for low-lying electronic states of SO_2

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Science china chemistry 2006年第4期49卷 289-295页

作者： LI Anyang1, SUO Bing2. WEN Zhenyi2.& WANG Yubin2.1. Shanxi Key Laboratory of Physico-inorganic chemistry, Department of chemistry, Northwest University, Xi’an 710069, china 2. institute of Modern Physics, Northwest University, Xi’an 710069, china Shanxi Key Laboratory of Physico-inorganic chemistry Department of Chemistry Northwest University Xi’an China institute of Modern Physics Northwest University Xi’an China

The potential energy surfaces for the nine low-lying electronic states of SO2.have been constructed by using the multi-reference second order perturbation theory (MRPT2. with the basis set cc-pVTZ. The optimized geometries and the adiabatic excitation energies of these states are in good agreement with experiments and previous calculations. The crossings and avoided crossings dis- played in the potential energy surfaces are expounded.

关键词： cross of PES, MRPT2. SO2 (sulfur dioxide).

Doubly contracted CI method and applications

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Science china chemistry 2004年第4期47卷 276-282页

作者： WANG Yubin1, HAN Huixian1, ZHAI Gaohong2.,SUO Bin1 & WEN Zheny1,2.1. institute of Modern Physics, Northwest University, Xian 710069, china 2. Laboratory of Physico-{2. chemistry, Department of chemistry, Northwest University, Xian 710069,china Correspondence should be addressed to Wen Zhenyi institute of Modern Physics Northwest University Xian China Laboratory of Physico-inorganic chemistry Department of Chemistry Northwest University Xi’an China

Based on the hole-particle correspondence an approximate so-called doubly contracted CI scheme is proposed. Examples calculated based on the doubly contracted CI (DCCI) scheme show that the number of configurations after contraction is reduced by three orders of magnitude, and the computation time is reduced by an order of magnitude. The examples also show that compared with experiments the DCCI and uncontracted CI have similar and reasonable accuracy to some spectroscopic parameters.

关键词： doubly contracted CI hole-particle symmetry approximate MRCI

Encapsulation of inorganic particles by dispersion polymerization through ultrasonic irradiation

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Science china chemistry 2005年第6期48卷 545-552页

作者： ZHANG Kai1,2. FU Qiang1, HUANG Yuhong2.& ZHOU Dehui2.1. College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, china 2. institute of Structure Mechanics, china Academy of Engineering Physics, Mianyang 62.900, china College of Polymer Science and Engineering Sichuan University Chengdu China institute of Structure Mechanics China Academy of Engineering Physics Mianyang China

The nano-silica/polystyrene composite particles were prepared and characterized according to the following steps. First, the nano-silica particles were pretreated with surfactants under ultrasonic field. Second, the dispersion polymerization of styrene in a water/ethanol (1/6, weight ratio) medium, with poly(N-vinyl pyrrolidone) (PVP) as stabilizer and 2.2.-azobisizobu- tyronitrile (AIBN) as initiator in the presence of nano-silica particles was initiated with N2.purging through ultrasonic irradiation by taking its advantages of multieffect, i.e. dispersion, crushing, activation, and initiation. Finally, the polymerization kinetics characteristics were studied, and the encapsulation of composite particles was investigated with optical microscope, SEM, TEM, FTIR, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).

关键词： composite particle, dispersion polymerization, ultrasonic irradiation.

Efficient degradation of dye pollutants using dioxygen mediated by iron(Ⅱ) 2.2.-bipyridine loaded layered clay catalyst under visible irradiation

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Science china chemistry 2006年第5期49卷 407-410页

作者： CHENG Mingming1,SUN Zhenying1,2.MA Wanhong1,CHEN Chuncheng1,ZHAO Jincai1 & WANG Zhengping2.1. Laboratory of Photochemistry,Center for Molecular Science,institute of chemistry,Chinese Academy of Sciences,Beijing 100080,china 2. Department of Chemical Engineering,Harbin Engineering University,Harbin 150001,china Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing China Department of Chemical Engineering Harbin Engineering University Harbin China

The organic-inorganic layered solid catalyst Fe(bpy)_3^(2.)-laponite was ableto photode-grade Rhodamine B (RhB) by activation of dioxygen under visible irradiation (λ > 42.nm), while the homogeneous aqueous solution Fe(bpy)_3^(2.) showed no photoactivity. The catalystcould be repeatedly used and retained its reactivity. The hybrid catalyst could be separated fromthe suspension by centrifugation or sedimentation. The TOC removal yield of RhB was *** oxygen species (ROS) formed during degradation was detected by EPR. A possible mechanismwas proposed on the basis of the experimental results.

关键词： laponite, Rhodamine B, molecular oxygen, visible light.

Three-dimensional configurations of organic/inorganic hybrid nanostructural blocks (I).A quantum mechanical investigation for ladder-like structure of vinylsilsesquioxane

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Science china chemistry 2004年第5期47卷 388-395页

作者： ZHANG Xingwen1,2. HU Lijiang1, HUANG Yudong1, SUN Dezhi2.& SUN Yi3 1. Department of Applied chemistry,Harbin institute of Technology, HUANG Yudong, Harbin 150001,{2. 2. Department of Environmental Engineering, Harbin institute of Technology, Harbin 150001,{2. 3. Department of Experimental Mechanics,Harbin institute of Technology, Harbin 150001,{2. Dept. of Applied Chem. Harbin Inst. of Technol. Harbin 150001 China Dept. of Environ. Eng. Harbin Inst. of Technol. Harbin 150001 China Dept. of Experimental Mech. Harbin Inst. of Technol. Harbin 150001 China

The organic/inorganic hybrid nanostructural vinylsilsesquioxanes (VSSO) were prepared from the hydrolytic condensation of vinyltrimethoxysilane (VMS). The proposed formu- las of VSSO were assigned with standard spectroscopic techniques, FTIR, NMR (1H, C and 13 2.Si) and MALDI-TOF MS, and a generic formula of the SSO, Tn(OH)x(OR’)y(x, y = 0, 1, 2.; n = 1, 2.; T = RSiO1.5 ?(x+y)/2.). Geometric parameters (Si-O and Si-C bond lengths, Si-O-Si and O-Si-O bond angles) and total energies of the multi-structures of VSSO were calculated by a quantum mechanical investigation and molecular symmetries. According to the results of the calculation, most molecules had stabler ladder structures than the cage isomers, therefore, the most probably reasonable and optimum structure of the VSSO system was the ladder type.

关键词： vinyltrimethoxysilane (VMS), silsesquioxanes (SSO), sol-gel process, quantum mechanical calculation, MNDO.

Preparation and Characterization of ZrO_2.Nanoparticles Capped by Trioctylphosphine Oxide (TOPO)

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Journal of Wuhan University of Technology(Materials Science) 2011年第4期26卷 611-614页

作者：马剑琪 School of chemistry and Environmental Science Shaanxi University of Technology State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

Monodisperse ZrO2.nanoparticles capped by trioctylphosphine oxide （TOPO） were prepared in non-aqueous solvent using in-situ synthesis method. Transmission electron microscopy（TEM）, X-ray diffraction（XRD）, X-ray photoelectron spectrometer（XPS）, Fourier transformation infrared spectroscopy （FTIR）, and thermogravimetric analysis（TGA） were adopted to characterize and investigate the size, structure, composition, and the binding manners between organic capping agent TOPO and inorganic ZrO2.nanocores of the as-prepared nanoparticles. In addition, the nanoparticles were also studied to determine their solubility and relative stability. The experimental results show that the prepared nanoparticles contain about 2.% organic capping shell TOPO, 75% inorganic ZrO2.nanocores, and can be easily dissolved and be stably disersed in non-polar organic solvents.

关键词： ZrO2.nanoparticles trioctylphosphine oxide (TOPO) monodisperse solubility

Silicon-phthalocyanine bonding with SiO_2.matrix and its strong optical limiting effects

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Chinese Science Bulletin 2000年第23期45卷 2198-2203页

作者： XIA Haiping, PU Bingyin, ZHANG Yuepin, ZHANG Jianli, FANG Jianghua & WANG CunkuanDepartment of chemistry, ningbo University,{2., china Correspondence should be addressed to Xia Haiping Department of chemistry Ningbo University Ningbo China

Silicon-phthalocyanine (SiPc) is chemically bonded to 3-aminopropltriethoxysilane (NH2.CH2.3Si(OC2.5)3, KH550) by the nucleophilic substituted reaction between the active chlorine of silicon dichlorine phthalocyanine (SiPcCI2. and amino-group of KH550. The reacted product is hybridized with 3-glycidoxypropltrimethoxysilane (CH2.CHCH2.(CH2.3Si(OCH3)3, KH560) with sol-gel processing to form sol-gel inorganic material with good physical-chemical and optical properties. Due to tethering SiPc to the network, the aggregation of SiPc is effectively prevented in sol-gel derived matrix, and the doping concentration of SiPc in the form of monomer in the matrix is greatly enhanced. The cross-linkage of SiPcCI2.and KH550 is estimated and confirmed with FT-IR spectra. The optical limiting effects (OLE) of the gel with different content of SiPc are investigated with a frequency double Q-switched Nd3+:YAG laser of 8 nsec. pulse.

关键词： silicon dichlorine phthalocyanine amino-group cross-linkage inorganic non-crystal matrix optical limiting effect.

Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

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Science china chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2.3, SUN Yele1 & WANG Zifa3 1. The Center for Atmospheric Environmental Study, Department of chemistry, Beijing Normal University, Beijing 100875, china 2. Center for Atmospheric chemistry Study, Department of Environmental Science & Engineering, Fudan University, Shanghai 2.0433, china 3. LAPC/NZC, institute of Atmospheric Physics, CAS, Beijing 10002., china The Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University Beijing China Center for Atmospheric chemistry Study Department of Environmental Science & Engineering Fudan University Shanghai China institute of Atmospheric Physics CAS LAPC/NZC Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 32.―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62. （38%―86%） of the total mineral aerosols in TSP, 69% （52.―90%） in PM10, and 76% （59%―93%） in PM2.5 in spring, and 69% （52.―83%）, 79% （52.―93%）, and 45% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only2.% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

Comparison of degradation reactions of Acid Yellow 61 in both oxidation processes of H_2._2.UV and O_3

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Journal of Environmental Sciences 2001年第3期13卷 304-310页

作者： WANG Yi zhong 1, A.Yedeler 2. A. Kettrup 2.1 Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, china 2.GSF institute of Ecological {2., Neuherberg, Postfach 112., 85758 Neuherberg, Germany) Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China GSF-institute of Ecological chemistry Neuherberg Postfach 1129 85758 Neuherberg Germany

The comparison of degradation of Acid Yellow 61 as a model dye compound in both oxidation processes of H 2. 2.UV and O 3 has been studied. When the decolorization rate of Acid Yellow 61 in both reactions presented similar, it was found there are some differences from the results of AOX removal and production of inorganic ions and organic acids. The results reveal that the H 2. 2.UV has beneficial effect on mineralization than O 3 only for degradation of Acid Yellow 61 solution and it is possible for enhancement of method efficiency by taking longer reaction time and addition of high concentration of oxidants.

关键词： oxidation process H 2. 2.UV O 3 dye compound