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Approach to the Relation of Mutual-Feed Joint-Variation in Groundwater Management Model

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Journal of Earth Science 2012年第3期23卷 349-358页

作者：李平卢文喜靳孟贵杨青春 college of chemistry and Materials South-Central University for Nationalities School of Environmental Studies China University of Geosciences college of Environment and Resources Jilin University

In groundwater management,the exchanges between groundwater and other water such as surface water and spring water need to be *** exchange is dependent on the ground-water level,which is called *** pumping rate,groundwater level,and covariate interact and the relation of mutual-feed joint-variation is used to describe their *** article presents a new approach of dealing with the relation in groundwater management *** mathematical for-mulation of the relation,as an additional equality constraint in the optimization model,is developed using response matrix *** the groundwater management model with covariate is set *** code for the simulation and management of groundwater system with covariate is programmed with Fortran 90,and the optimal pumping rate,groundwater level,and covariate are *** approach is verified with a hypothetical ***,the approach is applied to the groundwater management of Qianguo（前郭） area in western Jilin（吉林） *** results indicate that the ap-proach is *** provides a universal solution for various covariates and reduces the computational complexity compared to iteration *** approach is proven to be very efficient to solve ground-water management problem with covariate.

关键词： covariate relation of mutual-feed joint-variation groundwater management response matrix

Effect of Polymerization Condition on Particle Size Distribution in St/BA/MAA Emulsion Polymerization Process

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Chemical Research in Chinese Universities 2000年第1期16卷 67-71页

作者： TAN Bi-en (Material Science and Engineering college, South china {2. of Technology, Guanzhou 510641, P. R. china) ZHANG Hong-tao LI Jian-zong and HU Fang (Department of chemistry, hubei {2., wuhan 430062. P. R. china) 华南理工大学广东广州 510641 湖北大学湖北武汉 430062

A series of St/BA/MAA emulsion polymerizations was carried out. By using PCS (photon correlation spectroscopy), the particle size distribution (PSD) of the whole St/BA/MAA emulsion polymerization process was gotten e... 详细信息

关键词： Emulsion polymerization Particle size Latex Particle size distribution

Ammoxidation of Substituted Toluenes on Silica-Supported VPO Catalysts

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wuhan university Journal of Natural {2. 2002年第3期7卷 356-360页

作者： Xie Guang\|yong, Zheng Qiong , Huang Chi, Li Xiao\|yun, Yu Peng, Chen Yuan\|yin college of chemistry and {2. sciences, wuhan university, wuhan 430072. hubei, china college of chemistry and {2. sciences Wuhan University Wuhan 430072 Hubei China

The ammoxidation of substituted toluenes to their corresponding nitriles over silica-supported vanadium phosphorus oxide (VPO/SiO2. catalysts has been studied. the effects of carrier silica, the addition of phosphorus, the substituents and the loadings have been discussed. Compared with unsupported VPO, the VPO/SiO2.catalysts have higher catalytic activity for ammoxidation of substituted toluenes and much lower reaction temperature. XRD shows that vanadium phosphorus oxides exist as amorphous phase and disperse to a high degree on the silica surface in 10%loading catalyst. When the loadings are over 10%, the crystalline α-VOPO4 would emerge, which would decrease the yield and selectivity. Additional phosphorus can form composite oxides with vanadia and play concerted catalytic function, which increase the selectivity of nitriles remarkably. Different substituents or same substituents on different positions have different influences because of the variant electronic stability of intermediates, the hindered accessibility of methyl group or the chemisorption state of the substrate molecule on the electrophilic catalyst surface.

关键词： ammoxidation VPO/SiO2.catalyst substituted toluenes aromatic nitriles

Status of study on biological and toxicological effects of nanoscale materials

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Science china chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2.& JIA Guang3 1. Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of sciences, Beijing 100049,{2. 2. college of chemistry and molecular Engineering, Peking university, Beijing 100871,{2. 3. Department of Occupational and Environmental Health sciences, School of Public Health, Peking university, Beijing 100083,{2. Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences Beijing China college of chemistry and {2. Engineering Peking University Beijing China Department of Occupational and Environmental Health sciences School of Public Health Peking University Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

Preparation by a Rheological Phase Reaction Method and Thermal Decomposition Reaction Mechanism of Nickelous Salicylate Tetrahydrate

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wuhan university Journal of Natural {2. 2003年第3A期8卷 853-856页

作者： Wang Jin\|long, Yuan Liang\|jie, Yang Yi\|yong, Sun Ju\|tang , Zhang Ke\|li college of chemistry and {2. sciences, wuhan university, wuhan 430072. hubei, china college of chemistry and {2. sciences Wuhan University Wuhan 430072 Hubei China

The single crystal nickel salicylate tetrahydrate was prepared with the rheological phase reaction method from nickelous hydroxide and salicylic acid. The crystal structure was determined. It is monoclinic, space group P2. 1/n, a= 0.678 74 (3), b=0.515 91(2., c =2.313 30(9) nm, β= 90.92. 6(17)° , V =0.809 94(6) nm 3, Z=2. ρ calcd = 1.661 g\5cm -3 . Final R indices: R =0.02. 9 and wR= 0.065 0 \[I >2.(I)\]. The thermal decomposition mechanism in an inert atmosphere was investigated via TG, DTG and DTA. The thermal decomposition products were characterized with IR and micro\|powder X\|ray diffraction method. A new coordination polymer (NiC 6 H 4 O) n as an intermediate product and nanoscale metal nickel were obtained in the ranges of 364\|42. ℃ and 42.\|680 ℃, respectively.

关键词： nickelous salitylate tetrahydrate rheological phase reaction crystal structure thermal decomposition

Synthesis, Crystal Structures and Catalysis of Dinuclear Cd(Ⅱ) Complexes Bridged by Unusual (N,O,O′)-Coordinated α-Amino Acids

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Chemical Research in Chinese Universities 2012年第1期28卷 73-78页

作者： DENG Dong-sheng1,2. WANG Li1, PEI Ya-mei1, FENG Lu2.and LIU Chang-lin1 1. Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, School of chemistry, Central china Normal {2., wuhan 430079, P. R. china 2. college of chemistry and Chemical Engineering, Luoyang Normal {2., Luoyang 47102., P. R. china School of chemistry Central China Normal University Key Laboratory of Pesticide & Chemical Biology Ministry of Education Wuhan 430079 college of chemistry and Chemical Engineering Luoyang Normal University Luoyang 471022

Four dinuclear amino acid cadmium（II） complexes [Cd2.tren）2.dl-alaninato）]（ClO4）3·H2.（I）, [Cd2.tren）2. （l-alaninato）]（ClO4）3·H2.（II）, [Cd2.tren）2.dl-phenylalaninato）]（ClO4）3（III） and [Cd2.tren）2.l-phenylalaninato）]· （ClO4）3（IV）, constructed from mixed ligands of tris（2.aminoethyl）amine（tren） and racemic or natural amino ac ids（amino acids=dl or l-alanine, and dl or l-phenylalanine）, have been synthesized and characterized by X-ray crys tallography. The structural analysis of complexes I and III reveals that the cadmium centers are coordinated by one tren ligand and one amino acid molecule with the unusual （N,O,O′）-bridged mode, resulting in asymmetric chromo phores of CdN4O and CdN5O in complex I, CdN4O2.and CdN5O in complex III, respectively. The utility of the four complexes as efficient water-compatible Lewis acid catalysts for the direct aldol reaction in water was examined. The reaction proceeded smoothly to afford the corresponding β-hydroxy ketones in up to 99% yield. Moreover, the dias tereoselectivity of the reaction favors the formation of the syn-isomers.

关键词： Dinuclear cadmium(II) complex Amino acid Aldol reaction

Correlation of Behavior Changes and BOLD Signal in Alzheimer-like Rat Model

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3, Mai-Li LIU3, Rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2., and Jian-Zhi WANG1* Department of Physics and Bio-X disciplinary Laboratory, Zhejiang university, Hangzhou 31002.,china 1 Department of Pathophysiology, Tongji Medical {2., Huazhong university of Science and Technology, wuhan 430030, china 2.nstitute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques, Chinese Academy of sciences, P.O. Box 918, Beijing 100039, china 3wuhan Institute of Physics and Mathematics, State Key Laboratory of Magnetic Resonance and Atomic and molecular Physics, Chinese Academy of sciences, wuhan 430071, china Department of Physics and Bio-X disciplinary Laboratory Zhejiang UniversityHangzhou 310027China Department of Pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China wuhan Institute of Physics and Mathematics State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China Institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To explore a potential means for the early diagnosis of Alzheimer disease, we studied the relationship of resting T2. signal and tau hyperphosphorylation/spatial memory deficit. The rat model with tau hyperphosphorylation and spatial memory deficit was established by bilateral hippocampi injection of isoproterenol (IP). Then, the correlative alteration between resting T2. signal and spatial memory retention was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) study and Morris Water Maze test, and Western blot was employed to confirm tau hyperphosphorylation. The analysis showed following results. (1) Tau phosphorylation at Ser396/Ser404 and Ser199/Ser2.2.was signifi- cantly increased in IP-injected rats as detected by PHF-1 and tau-1, respectively. (2. An AD-like spatial memory retention disturbance was induced at 2. h after isoproterenol injection. (3) A sensitivity threshold of resting T2. signal intensity, which separated the IP-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 32.62. These results suggest that resting T2. signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperphosphorylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isoproterenol (IP) Morris Water Maze diagnosis

室内空气环境中微(痕)量甲醛的主要分析方法

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武汉大学学报（理学版） 2001年第4期47卷 433-437页

作者：安从俊丁哨兵杨波郑丹武汉大学化学与分子科学学院湖北武汉430072 荆门职业技术学院化工系湖北荆门448000

综合评述了目前国内外关于室内空气环境中微 (痕 )量甲醛的来源、危害和几种主要采样、分析方法以及最新发展的分析检测技术 ,比较了各类分析方法的优缺点并提出了今后的发展方向 .

关键词：室内空气环境甲醛分析方法采样分离分光光度法色谱法

Synthesis of 2. 4-Dibromo-5-Fluorobenzonitrile

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wuhan university Journal of Natural {2. 1998年第4期3卷 509-510页

作者： Zheng Qiong Huang Chi Xu Chongwen Xie Guangyong Chen Yuanyin(college of chemistry,{2., wuhan 430072. china) wuhan university College of Chemistry Wuhan China (GRID:grid.49470.3e) (ISNI:***)

2.4-Dibromo-5-fluorobenzonitrile has been synthesized for the first time (81.5% yield). It may be used in synthesizing 2.4-dibromo-5-fluorobenzoic acid, the intermediates of fluoroquinolones. The ammoxidation procedur... 详细信息

关键词： ammoxidation 2.4-dibromo-5-fluorobenzonitrile 2.4-dibromo-5-fluorobenzoic acid fluoroquinolone