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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,{2. of chemistry,chinese academy of sciences,beijing 100080,China 2. department of Chemical Engineering,Harbin Engineering University,Harbin 150001,China 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

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.

TRANSIENT EFFECT OF A BOGER FluID FLOWING AROUND A CONFINED CYLINDER

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chinese Journal of Polymer Science 2001年第4期19卷 377-384页

作者： Xian-feng Li Huai-tian Bu De-lu Zhao State Key Laboratory of Polymer Physics and {2. Center for Molecular Science,{2. of {2., chinese academy of sciences, beijing 100080, China chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Polymer Phys & Chem Beijing 100080 Peoples R China

This paper is concerned with the numerical simulation of the transient effect of an inertialess Boger flow past a confined circular cylinder and the comparison of predictions with particle image velocimetry (PIV) measurements given by Shiang et al.. Dynamic simulation based on the Oldroyd-B constitutive model was carried out using a Lagrangian-Eulerian algorithm. The evolution of velocity field was obtained for the flow at two Deborah (De) numbers, i.e. De = 1.2.and 3.0. At low De, the flow reached steady state rapidly, and showed a symmetric flow regime. However, at high De, the time required to reach steady flow behind the cylinder increased significantly, and the distribution of the velocity field appears to be asymmetric with respect to the stagnation line. Fairly good agreement between the numerical results and the experimental observations is reported. It can be concluded that both the experimental measurements and the present simulations indicate that the elasticity of the polymeric flow strongly affect the flow regime of viscoelastic flow around a confined cylinder.

关键词： transient effect flow around a cylinder Lagrangian-Eulerian algorithm Oldroyd-B model

Enhancement Effect of Gold Nanoparticles on the Bioactivity of Hydrogen-producing Microbe

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Journal of Wuhan University of Technology(Materials Science) 2006年第4期21卷 16-18页

作者：刘光臻 institute of chemistry Chinese Academy of Sciences Beijing 100080China

In order to increase the yield of hydrogen production for hydrogen-producing microbe, the enhancement effect of nanometer- sized gold panicles on the activity of hydrogen-producing microbe was studied. The yields of hydrogen production in the system added by gold nanoparticles of 6 nm and 12.nm in diameter were obviously increased by about 17% and 9% in contrast to that in blank system. The experimental restdts indicate that gold nanoparticles could significantly enhance the bioactivity of hydrogen-producing microbe.

关键词： gold nanoparticles bioactivity hydrogen-produeing microbe

Comparative study of the effect of Cu_2. and MoO_3 on flame retardance and smoke emission of PVC by Cone and TGA

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chinese Science Bulletin 1998年第13期43卷 1090-1094页

作者： LI Bin\+1 and WANG Jianqi\+2.1. department of chemistry, Northeast Forestry University, Harbin 150040, China 2. National Laboratory of Flame Retardant Materials, {2. institute of Technology, {2., 100081, China department of chemistry Northeast Forestry University Harbin China National Laboratory of Flame Retardant Materials Beijing Institute of Technology Beijing China

Cuprous and molybdic oxides exhibit extremely effectiveness in smoke suppression for PVC. However, few are the data reported concerning flame retardance and smoke emission of PVC taken from Cone calorimetry relative to the conventional thermal analysis technique. Abundant data from Cone calorimetry have been acquired. Data analysis was achieved through the study of MLR, HRR, SEA tested at irradiance of 2. kWm -2.. The understandable flame retardance of PVC/Cu\-2. and PVC/MoO\-3 relative to pure PVC has been rationalized by their lowered heat release rates and enhanced char residues. The difference in smoke reduction between these two oxides consists in the time scale. As clearly seen under air atmosphere both oxides exert themselves to the afterglow which has been recognized as a dangerous source, in particular in the full_scale fire situation.

关键词： cone calorimetry poly(vinyl chloride) flame retardation smoke emission cuprous oxide molybdic oxide.

Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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chinese Science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2. ZHUANG Guoshun1,2.3, CHEN Jianmin2.& XUE Huaxin2.1. Center for Atmospheric Environment Study, department of chemistry, {2. Normal University, {2. 100875, China 2. Center for Atmospheric chemistry Study, department of Environ- mental Science and Engineering, Fudan University, Shanghai 2.0433, China 3. LAPC/NZC, institute of Atmospheric Physics, NZC/LAPC, chinese academy of sciences, {2. 10002., China Center for Atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China Center for Atmospheric chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China LAPC/NZC Institute of Atmospheric Physics NZC/LAPC Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2.Al2.3. Sulfate is the dominant species of sulfur on the surface. SiO2.and Al2.3 are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4) produced could account for up to 44.3% and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 2., 2.02. while Fe2.SO4)3, one of the Fe(III) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3%?5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合

Phase relationship of complex multi-component system in chromate cleaner production

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Progress in Natural Science:Materials International 2007年第7期17卷 845-850页

作者： Ge Xinlei~1 Wang Xidong~(1,3**) Zheng Shili~2.Zhang Mei~1 Zhang Yi~2.(1.department of Physical chemistry,University of Science and Technology {2.,{2. 100083,China 2.institute of Process Engineering,chinese academy of sciences,{2. 100080,China 3.College of Engineering,Peking University,{2. 100871,China) [a]department of Physical chemistry University of Science and Technology Beijing Beijing China [b]College of Engineering Peking University Beijing China [c]institute of Process Engineering Chinese Academy of Sciences Beijing China

The phase relationships of the complex multi-component systems in the liquid-phase oxidization and separation process related with the chromate cleaner production are investigated theoretically and *** phase diagram of main system Fe- Cr2.4-KOH-O2.f oxidization process and the relationship of its standard Gibbs free energy change with temperature are calculated.A se- ries of phase diagrams of the separation process at different temperatures,such as K（Na）OH-K（Na）2.rO4-H2.,KOH-KAlO2.H2., K（Na）OH-K（Na）2.O3-H2.,K（Na）OH-K（Na）HCO3-H2. and K（Na）HCO3-K（Na）2.rO4-H2. have also been *** ex- periments are carried out to verify the calculated *** results showed that the sub-molten salt media are suitable for the oxidization and separation processes;FeCr2.4can be oxidized across a wide range of temperature;K（Na）2.rO4can be separated from K（Na）AlO2.ystem at appropriate temperature and proper concentration;the crystallization of carbonate is easier than that of K（Na）2.rO4.

关键词： chromite chromate system thermodynamics calculation phase diagram

Solvation effects on brain uptakes of isomers of ^(99m)Tc brain imaging agents

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chinese Science Bulletin 2002年第21期47卷 1786-1791页

作者： JIA Hongmei, MA Xiaohui, WANG Cunxin & LIU Boli1. department of chemistry, {2. Normal University, {2. 100875, China 2. Center for Biomedical Engineering, {2. Polytechnic University, {2. 10002., China 1. department of chemistry Beijing Normal University Beijing 100875 China 2. Center for Biomedical Engineering Beijing Polytechnic University Beijing 100022 China

Analysis of electrostatic hydration free energies of the isomers of the 99mTc-BAT and 99mTc-DADT complexes is carried out using the computer simulation technique. The results show that not only a correlation exists between the logarithm of the brain uptake and the electrostatic hydration free energy for the isomers of 99mTc-brain radiopharmaceu-ticals, but also a linear relationship exists between the logarithm of the ratio of the brain uptake of the syn isomer to that of the anti one and the difference between the electrostatic hydration free energy of the syn-isomer and that of the anti one. Furthermore, the investigation on the important factors influencing the brain uptakes of 99mTc-radiophar-maceuticals and the reasons of the different biodistribution of the isomers of the 99mTc-complexes is explored at the molecular level. The results may provide a reference for the rational drug design of brain imaging agents.

关键词： 99mTc-brain imaging agent isomer brain uptake electro-static hydration free energy.

Polymerization of Bisphenol A Epoxy Resin with Polyethylene glycol

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chinese Chemical Letters 1997年第8期8卷 725-728页

作者： Zhen Zhong YANG De lu ZHAo Mao XU(Polymer Physics Laboratory, institute of {2., The {2. academy of sciences, beijing 100080) chinese ACAD SCI INST CHEMPOLYMER PHYS LABBEIJING 100080PEOPLES R CHINA

The catalyst boron trifluoride etherate was used to catalyze the reaction of epoxy resin with polyethylene glycol (PEG), and the effect of the concentration of the catalyst on the reaction is studied. It is shown that there exist two competitive reactions : I, self polymerization of epoxy resin via chain growth and II, copolymerization of epoxy resin with PEG via step growth. At high concentration of the catalyst reaction I dominates and reaction II is negligible. On the contrary, at low concentration of the catalyst, reaction II dominates and block copolymers are formed In the intermediate case, the two reactions are comparable with the result that a gel structure is obtained.

关键词： PEG Polymerization of Bisphenol A Epoxy Resin with Polyethylene glycol

SYNTHESIS　AND　SPECTROSCOPIC　PROPERTIES　OF　AN　AMINO　ACID　MODIFIED　PHTHALOCYANINE

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chinese Chemical Letters 1996年第5期7卷 399-400页

作者： Run An DONG Wong QIU Xin Qi SONG (department of chemistry, Tsinghua University, {2. 100084)De Wen CHEN (institute of Chemisty The chinese academy of Science, beijing 100080) department of chemistry Tsinghua University Beijing 100084 institute of Chemsity Chinese Academy of Science Beijing 100080

Abstract: One amino acid modified phthalocyanine was synthesized and its absorption was measured. And a red shift up to 2. nm relative to ZnPc(NH2.4 was *** recent years, phthalocyanines are widely used in photodynamic therapy (PDT) and ligntinduced eleCtronic d..ices(i), because they can be potentially used in the therapy of cancer andin the restraint of human immunology virus (HIV)etcq'. In order to study the relationship betweenthe molecular struCture and its propeFties, various kinds of phthaloCyanines have beensynthesized, however phthaiocyanines modified by amino acid have not been reported it isexpeCted that the introduCtian of an amino acid group onto the phthalocyanine molecuje cauldimprove the solubility of such dyes in physiological system. In this work,a phthalocyaninemodified by glycine was synthesized and identified by conventional method, and its UV- Visspectra were obtained.

关键词： ACID MODIFIED PHTHALOCYANINE OF AN AMINO

RHEOLOGICAL BEHAVIOR OF EPOXY RESIN WATERBORNE DISPERSIONS

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chinese Journal of Polymer Science 2001年第5期19卷 471-476页

作者： Zhen-zhong Yang Yuan-ze Xu De-lu Zhao State Key Laboratory of Polymer Physics & chemistry, Center for Molecular Science {2. of chemistry, chinese academy of sciences, beijing 100080 China chinese Acad Sci Inst Chem State Key Lab Polymer Phys & Chem Ctr Mol Sci Beijing 100080 Peoples R China

The waterborne dispersions of epoxy resin were prepared by the phase inversion emulsification technique. Rheological behavior and its relationship with the structural change of the systems were studied. It was shown that the concentrated dispersions were highly viscoelastic and pseudoplastic, which was attributed to the formation of a physical network among the waterborne particles via hydrogen bond. The dilute dispersions were Newtonian fluids. The discrete clusters composed of small waterborne particles were found in diluted dispersions. With increasing solid content, there existed a structural transition via percolation through a cluster-cluster aggregation mode to form the physical network, which was qualitatively evidenced by the TEM morphologies.

关键词： epoxy resin waterborne dispersion rheological behavior cluster-cluster aggregation percolation transition