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science China chemistry 2009年第9期52卷 1470-1478,1523-1524页

作者： LI ChengPeng, YU Qian & DU Miao college of chemistry and {2. {2., tianjin Key Laboratory of Structure and Performance for Functional Molecule, tianjin normal university, tianjin 300387, China college of chemistry and {2. {2. Tianjin Key Laboratory of Structure and Performance for Functional Molecule Tianjin Normal University Tianjin China

A series of Cd(Ⅱ) coordination complexes with an elongated 2.4-dipyridyl-type building block trans-1-(2.pyridyl)-2.(4-pyridyl)ethylene (bpe) and different dicarboxylate ligands have been presented. Generally, bpe shows the unidentate coordination mode and serves as the terminal pendant, whereas the dicarboxylate ligands display various binding fashions to interlink the metal centers to form 1-D comb-like chain, ribbon, and fishbone arrays, as well as 2.D 44 and 4.82.layered networks. Notably, the bpe building block is also involved in secondary interactions such as hydrogen bonding and aromatic stacking to construct the resulting supramolecular architectures. Thermal stability of these complexes has been studied by TG-DTA technique.

关键词： crystal engineering coordination supramolecular framework Cd(Ⅱ) complex secondary interaction thermal stability

Homotopy type of smooth weighted complete intersections

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science China Mathematics 2010年第6期53卷 1583-1594页

作者： WANG JianBo1,& WANG YuYu2.1Department of Mathematics,tianjin university,tianjin 300072.China 2.3} of Mathematical science,tianjin normal university,tianjin 300387,China 1. Department of Mathematics Tianjin University Tianjin 300072 China2. College of Mathematical Science Tianjin Normal University Tianjin 300387 China

If the total degree d has no prime divisors less than(n+3)/2.then we prove that the homotopy type of complex odd dimensional smooth weighted complete intersection Xn(d;w) is determined by the dimension n,the total degree d,the Euler characteristic and the Kervaire invariant,provided that the weights w =(ω0,...,ωn+r) is pairwise relatively prime.

关键词： weighted projective space weighted complete intersection homotopy type connected sum

RuCl_3·3H_2. Mediated Olefin Isomerizations in Ionic Liquids: A Highly Recyclable System for Olefin Isomerizations

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Chemical Research in Chinese Universities 2012年第1期28卷 67-69页

作者： SHAO Ming-bo1, LIU Gui-yan2. ZHAO Jing-jing1, WANG Xiao-yu1 and WANG Jian-hui1 1. Department of chemistry, college of{2., tianjin university, tianjin 300072. P. R. China 2. tianjin Key Laboratory of Structure and Performance for Functional Molecule, college of chemistry, tianjin normal university, tianjin 300387, P. R. China Department of chemistry College of Science Tianjin University Tianjin 300072 college of chemistry Tianjin Normal University Tianjin Key Laboratory of Structure and Performance for Functional Molecule Tianjin 300387

Herein lies a convenient and highly efficient method of olefin isomerization in the presence of RuCl3？3H2. in ionic liquid（IL）. More importantly, RuCl3？3H2. is a robust and recyclable catalyst. Nine cycles of RuCl... 详细信息

关键词： Ruthenium trichloride Ionic liquid Olefin isomerization

Raising medium function of environmental engineering by using life rubbish to produce carpet turf

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Journal of Environmental sciences 2000年第4期12卷 498-505页

作者： DUO Li an, ZHAO Shu lan (college of chemistry and Biology,{2., tianjin 300074, China) 天津师范大学天津 3 0 0 0 74

Abundant material with low cost was utilized to raise medium function of producing carpet turf by life rubbish. The results showed that the material used could strikingly raise water retentiveness and ventilating of medium. Through the determination of the effect of each growth index of several turfgrass, emergence density, plant height, root growth and individual plant′s net primary production were all positively related to the material′s amount mixed, showing that the mixture of material could promote turfgrass growth, further proving that the material used raised medium function of producing carpet turf by life rubbish and made most use of life rubbish resources. It provided a scientific base is for application of environmental engineering by using life rubbish to produce carpet turf. So the study had both important theoretic meaning and applied value.

关键词： life rubbish carpet turf medium function environmental engineering

Influence of modulation ratio on structure and properties of nanoscale ZrB_2.ZrAlN multilayered coatings

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science China(Technological sciences) 2010年第3期53卷 772-775页

作者： LI DeJun 1,KANG YuanBin 1,DONG Lei 1,DENG XiangYun 1,LIU Hao 2.&SUN XueLiang 2.1college of Physics and Electronic Information science,{2. normal university,{2. 300387,China 2.Department of Mechanical&Materials Engineering,university of Western Ontario,London ON,Canada 1. college of Physics and Electronic Information science Tianjin Normal University Tianjin 300387 China2. Department of Mechanical & Materials Engineering University of Western Ontario London ON Canada

ZrB2.ZrAlN multilayered coatings with various modulation ratios(t ZrB2.t ZrAlN)and constant modulation periods were prepared by magnetron sputtering system at room ***,XRD,surface profiler and nano-indenter were employed to investigate the influences of tZ rB 2.tZrAlNon the microstructure and mechanical properties of the *** interfaces and nanoscale multilayered modulation were confirmed by *** multilayer with modulation period of 40 nm and ratio of 3:1 displayed the highest hardness(36.4 GPa)and critical fracture load(76.477 mN)with lower *** polycrystalline structure and multilayered modulate structure were directly responsible for the enhanced mechanical properties.

关键词： ZrB2.ZrAlN multilayered coating magnetron sputtering modulation ratio nanoscale

Influence of MnO_2.on the photocatalytic activity of P-2. TiO_2.in the degradation of methyl orange

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中国科学：化学英文版 2008年第2期51卷 179-185页

作者： LI ShunJun1, MA ZiChuan1,2. WANG Lin1 & LIU JingZe2.1 college of chemistry and Material{2.s, Hebei normal university, Shijiazhuang 050016, China 2.college of life{2., Hebei normal university, Shijiazhuang 050016, China college of chemistry and Material{2.s Hebej Normal UniversityShijiazhuang 050016China college of life {2. Hebei Normal UniversityShijiazhuang 050016China

Influences of α-MnO2. β-MnO2. and δ-MnO2.on the photocatalytic activity of Degussa P-2. TiO2.have been investigated through the photocatalytic degradation of methyl orange. The TiO2.photocatalyst, before and after being contaminated by MnO2. was characterized by UV-visible diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS). The results showed that photocatalytic activity of TiO2.could be inhibited significantly or completely deactivated due to the presence of even a small amount of MnO2.particles. It was found that the poisoning effect varied with the crystal phases of MnO2.and the effect was in the order δ-MnO2.>α-MnO2.>β-MnO2. The poisoning effect was attributed to the formation of heterojunctions between MnO2.and TiO2.particles. The heterojunctions changed the chemical state of Ti4+ and O2.sites in the crystalline phase of TiO2. MnO2.in contact with TiO2.particles also broadens the band-gap of TiO2. which decreases UV absorption of TiO2. It can also create some deep impurity energy levels serving as photoelec-tron-photohole recombination center, which accelerates the electron-hole recombination.

关键词： TiO2 MnO2 deactivation photocatalysis methyl orange

Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2.Zhao-Feng JIANG~2. 1 college of life {2.,Capital {2. university,Beijing 100037,China 2.college of Applied {2.s and Humanities,Beijing Union university,Beijing 100083,China college of life {2. Capital Normal UniversityBeijing 100037 China college of Applied sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2.and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

The effects of modulation period,modulation ratio,and deposition temperature on microstructure and mechanical properties of ZrB_2.W multilayers

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science China(Technological sciences) 2010年第9期53卷 2350-2354页

作者： LIU MengYin,TAN Ming,LIU GuangQing,WANG HaiYuan,XUE FengYing,DENG XiangYun & LI DeJun college of Physics and Electronic Information science,{2. normal university,{2. 300387,China 1. college of Physics and Electronic Information science Tianjin Normal University Tianjin 300387 China

Monolithic ZrB2.W coatings and ZrB2.W multilayers with different modulation periods and modulation ratios were synthesized by ion beam assisted deposition at room temperature and 400°C.X-ray diffraction (XRD),scanning electron microscopy (SEM),surface profiler,and nanoindention were employed to investigate the influences of the deposition temperature and the modulation period on the growth,textures,interface structure,and mechanical properties of the *** results indicated that the multilayer with modulation period of 13 nm synthesized at room temperature possessed a higher hardness of 2..8 *** temperature gave a significant contribution to mechanical property *** 400°C-deposition temperature led to a maximum hardness and elastic modulus value of 32.1 and 399.1 GPa for ZrB2.W multilayer with a modulation period of 6.7 *** critical load increased to 42.8 mN and residual stress decreased to -0.7 GPa.A higher deposition temperature can cause an increase in interfacial atomic mixture and mobility of surface species,which induceds an increase in areal atomic density and dislocation *** results as well as small nanoscale grain sizes should be related to hardness increase.

关键词： ion beam assisted deposition nanoscale multilayers modulation period modulation ratio deposition temperature hardness

The toxicity of Cu^(2.) to Microcystis aeruginosa using dielectric spectroscopy

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science China chemistry 2010年第3期53卷 631-636页

作者： YU YanLi1,BAI Wei1,ZHAO KongShuang1& ZHOU YunLong2.1college of chemistry,Beijing{2. university,Beijing 100875,China 2.0} of life science,Beijing{2. university,Beijing 100875,China 1. college of chemistry Beijing Normal University Beijing 100875 China2. College of Life Science Beijing Normal University Beijing 100875 China

Dielectric spectroscopy(DS) was utilized to investigate the toxicity of the Cu2. solution to Microcystis *** was found that 0.04 mM Cu2. had no effect on dielectric increment,whereas the Cu2. concentrations above 0.1 mM decreased the value of Δε/Δε *** toxic effect of Cu2. on *** cells was time-dependent and *** was a threshold concentration between 0.04 mM and 0.1 mM,which affected the cell membrane,suggesting that Cu2. at the concentrations higher than 0.1 mM caused serious plasmalemma damage to *** *** addition of 1 mM Ca2. or Mg2. did not protect *** cells from 1 mM Cu2. *** study demonstrates that DS monitors cell biomass facilitating observation of the toxic effects of metal ions.

关键词： Microcystis aeruginosa dielectric spectroscopy dielectric increment cupric ion toxicity

Chiral Mn(Ⅲ) salen complex immobilized on imidazole-modified mesoporous material via co-condensation method as an effective catalyst for olefin epoxidation

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science China chemistry 2009年第9期52卷 1417-1422页

作者： LOU LanLan1, YU Yi1, YU Kai2. JIANG Shu1, DONG YanLing1 & LIU ShuangXi1 1 Institute of New Catalytic Materials science, college of{2., Nankai university, tianjin 300071, China 2.college of Environmental science and Engineering, Nankai university, tianjin 300071, China Institute of New Catalytic Materials science College of Chemistry Nankai University Tianjin China college of Environmental science and Engineering Nankai University Tianjin China

An imidazole modified mesoporous material has been prepared through a co-condensation procedure and adopted to covalently anchor chiral Mn(Ⅲ) salen complex. The active centers in the as-synthesized catalyst were presented in the form of ionic species. The results of XRD, FTIR, DRUV-Vis, and N2.sorp-tion confirmed the successful immobilization of chiral Mn(Ⅲ) salen complex inside the channels of the modified support and the maintenance of the mesoporous structure of parent support in the immobi-lized catalyst. This heterogeneous catalyst exhibited comparable catalytic activity and enantioselectiv-ity to those of the homogeneous counterpart in the asymmetric epoxidation of unfunctionalized olefins. Furthermore, notably high turnover frequencies have been obtained over this heterogeneous catalyst for the relatively short reaction time and low catalyst amount, due in part to the ionic property as well as the uniform distribution of the active centers.

关键词： imidazole-functionalized mesoporous material chiral Mn(Ⅲ) salen complex co-condensation asymmetric epoxidation unfunctionalized olefins