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SILICA-SUPPORTED NICKEL AND ZIRCONIUM CATALYSTS FOR BRANCHED POLYETHYLENE

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chinese Journal of Polymer Science 2003年第4期21卷 453-458页

作者：孙文华 State Key Laboratory of engineering Plastics The center for Molecular sciences Institute of chemistry chinese academy of sciences beijing 100080 china chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Engn Plast Beijing 100080 Peoples R China

8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.

关键词： 8-Aminoquinoline nickel dichloride, Cp_2ZrCl_2 Silica supported catalysts Branched polyethylene

Regional air quality prediction models using the knowledge－based system approach

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Journal of environmental sciences 1995年第1期7卷 66-73页

作者： Du Min Bai Naibin Yao Guian(research center for eco-environmental sciences,chinese academy of sciences,beijing 100085,china)Yuan Jiwen Shen Baoling(Tianjin environmental Monitoring center,Tianjin 300191,china) Rsch Ctr for eco-Envmtl sciences Chinese Academy of Sci Beijing China China

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关键词： expert system air quality assessment knowledge-based systems.

Subchronic toxicological effects of aquatic nitrobenzene on Medaka and chinese rare minnow

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Science china chemistry 2007年第5期50卷 707-717页

作者： ZHOU QunFang1, FU JianJie1,2, MENG HaiZhen1,2, ZHU XueYan1,2, JIANG GuiBin1, ZHANG JianBin1, LIU JieMin2 & SHI GuoQing2 1 State Key Laboratory of environmental chemistry and ecotoxicology, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china 2 Department of chemistry, school of Applied Science, university of Science and Technology beijing, beijing 100083, china State Key Laboratory of environmental chemistry and ecotoxicology ResearchCenter for Eco-environmental SciencesChinese Academy of SciencesBeijing 100085China Department ofchemistry School of Applied ScienceUniversity of Science and Technology B

Based on the simulative exposure experiments of nitrobenzene to two small experimental fishes, Medaka (Oryzias latipes) and chinese Rare Minnow (Gobiocypris rarus), it was found that nitrobenzene could decrease in a linear way in the static aquatic system. Both fishes could accumulate dose-related levels of nitrobenzene quickly and eliminate the compound rapidly when they were transferred to clean water. The chinese rare minnow showed more sensitivity to the acute toxicity exposure of nitrobenzene than Medaka. Typical molecular biomarkers in oxidative defense system including superoxide dismu- tase (SOD), catalase (CAT) showed the chemical induced alterations. The changes of acetylcholi- nesterase (AChE) activities indicated that nitrobenzene might affect the normal neural function. Nitro- benzene exposure could also lead to obvious damaging effects on the target organs, such as gill and liver by hitopathological studies.

关键词： nitrobenzene, Medaka, chinese rare minnow, bioaccumulation, elimination, molecular biomarkers, histopathological effects

Quantitative　model　for　species　distribution　of　hydroxy　polyaluminum　chloride

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Journal of environmental sciences 1997年第3期9卷 45-53页

作者： Feng Li, Luan Zhaokun, Tang Hongxiao research center for eco environmental sciences, chinese academy of sciences, beijing 100085, china

The species distribution of hydroxy polyaluminum chloride (PAC, Al T=0.1mol/L) solutions prepared through two different types of base injection was studied and compared quantitatively by Al Ferron timed complex colorimetric method(AFM) and 27 Al NMR spectroscopy method (ANM), and was simulated by using a quantitative calculating procedure of chemical equilibrium in MINEQL model. The results suggest that methodology of synthesis is very important for determining species distribution in the preparation of PAC solutions. In the PAC solution prepared by micro injection of base method(MIBM), there are at least five kinds of species including a kind of monomeric species Al 3+ , three kinds of polymeric species Al 2(OH) 4+ 2, Al 7(OH) 4+ 17 , Al 13 O 4(OH) (7- n )+ 24+ n ( n =0,2)and an aggregate of Al 13 or a solid phase Al(OH) 3 (aq.). Whereas in the PAC solution prepared by instantaneous injection of base method (IIBM), there are a kind of monomeric species Al 3+ , two kinds of polymeric species Al 2(OH) 4+ 2, Al 13 O 4(OH) (7- n )+ 24+ n ( n =0,2) and a solid phase Al(OH) 3(am). The change of species distribution in the PAC solution depends on preparing method, B(OH/Al) value and concentration.

关键词： polyaluminum species distribution quantitative analysis model calculation.

environmental Soil Phosphorus Testing and Phosphorus Release in Taihu Lake,china

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Pedosphere 2004年第4期14卷 461-466页

作者： HUANGQing-Hui WANGZi-Jian WANGDong-Hong： MAMei JINXiang-Can Graduateschoolofthechineseacademyofsciences Beijing（China）

A microtiter plate assay (MPA) for soluble reactive phosphorus (SRP) was applied to samples in overlying water and pore water as well as in three forms of environmental soil test phosphorus (P) types: water soluble phosphorus (WSP),diluted calcium chloride extractable phosphorus (PCaCl2), and Olsen-P in the sediments of Taihu Lake, china, where potential P release in response to pH was analyzed. MPA for rapid P analysis was shown to be promising when applied on samples of natural water and sediment extracts. Concentrations of WSP and PCaCl2 in the sediments were much lower than those of Olsen-P. Olsen-P levels in the littoral sediments along the north coast of Meiliang Bay in Taihu Lake (80to 140 mg kg-1) were much higher than those in the mouth of the bay (less than 50 mg kg-1). The risk of P release in the mouth area of Meiliang Bay was lower than that in the north littoral zone with a risk of sediment P release induced by pH increases.

关键词： bioavailability microplate phosphorus release risk

Adsorption of zinc on manganite(γ-MnOOH): particle concentration effect and adsorption reversibility

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Journal of environmental sciences 2004年第4期16卷 627-630页

作者： QIN Yan-wen1, PAN Gang 1,2,, ZHANG Ming-ming1, LI Xian-liang1 (1. State Key Laboratory of environmental Aquatic chemistry, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china. 2. Qingdao university of Science & Technology, Qingdao 266042, china) State Key Laboratory of environmental Aquatic chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

The adsorption and desorption processes of Zn(Ⅱ) on γ-MnOOH as a function of particle concentrations(C p) were studied. An obvious C p effect was observed in this adsorption system. The degree of adsorption hysteresis increased greatly with the increasing of C p, indicating that the extent of the real metastable-equilibrium states deviating from the ideal equilibrium state was enhanced with the increasing of C p. The C p-reversibility relationship confirmed the metastable-equilibrium adsorption(MEA) inequality(Pan, 1998a), which was the core formulation of the MEA theory. Because the MEA inequality was based on the basic hypothesis of MEA theory that adsorption density Γ is not a state variable, the C p-reversibility relationship gave indirect evidence to the basic hypothesis of MEA theory.

关键词： zinc γ-MnOOH adsorption reversibility

Distribution and origin of biologically available phosphorus in the water of the Meiliang Bay in summer

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Science china Earth sciences 2006年第z1期49卷 146-153页

作者： HUANG Qinghui, WANG Zijian, WANG Donghong, MA Mei & WANG Chunxia State Key Laboratory of environmental Aquatic chemistry, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china Key Laboratory of Yangtze Aquatic Environment (Ministry of Education), College of environmental Science and engineering, Tongji university, Shanghai 200092, china chinese Acad Sci Ecoenvironm Sci Res Ctr State Key Lab Environm Aquat Chem Beijing 100085 Peoples R China Tongji Univ Coll Environm Sci & Engn Minist Educ Key Lab Yangtze Aquat Environm Shanghai 200092 Peoples R China

The investigation and continuous monitoring with an innovative iron oxide embedded cellulose acetate membrane (FeO/CAM) on the concentrations of biologically available phosphorus (BAP) were conducted in the Meiliang Bay of the Taihu Lake during summer in 2004. The results showed that the concentrations of dissolved (FeO-DP), particulate (FeO-PP) and total bioavailable phosphorus (FeO-P) had similar horizontal distribution. The BAP concentrations were the highest in those estuaries in the northern bay. With the decrease of the distance to the estuary or long shore,there was little difference between BAP concentrations in an open lake area. During the observation period, algal blooms occurred in most waters of the northern bay, which was reflected from the high concentrations of chlorophyll a (Chl-a). While they were not highest in the estuarine waters of those major rivers, this is the case for the BAP concentrations. The concentrations of Chl-a had a significantly positive correlation with those of bioavailable phosphorus in the open area of the Meiliang *** the sediment resuspension induced by wind and wave, BAP concentrations increased in a short-term, indicating that the riverine P inputs mainly contribute to the concentrations of BAP in the estuarine water while internal P release was the major source of BAP in the open lake area. In the eutrophic shallow lake, the blooms of alga may cause pH increase and further result in internal P release. The above results showed that the new membrane of FeO/CAM can be used to monitor the concentrations of BAP and provide the scientific justifications for the control strategy of the lake eutrophication.

关键词： phosphorus, bioavailability, eutrophication, resuspension, Taihu Lake.

Effects of combined substitution of Dy and Mo or Si on the crystal structures and magnetic properties of Nd_(1-y)Dy_yFe_(11-x)TiM_x(M=Mo,Si) compounds

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Science china chemistry 2009年第8期52卷 1097-1103页

作者： LI XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin College of chemistry and chemical engineering,Graduate university of chinese academy of sciences,beijing 100049,china 1. College of chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12-type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

Detection of Peptide Damage Induced by Fenton Reaction with Electrochemical Biosensor

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生物物理学报 2009年第S1期25卷 400-401页

作者： Na Qu, Liang-Hong Guo and Ben-Zhan Zhu State Key Laboratory of environmental chemistry and ecotoxicology, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china.

Hydroxyl radical is one of the most reactive oxygen species (ROS) in biological systems, which can react with proteins and result in protein oxidation and damage. Oxidative

关键词： Electrochemical Biosensor Peptide Damage Fenton Reaction Hydroxyl radical