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Preparation and Properties of FeZrB Amorphous-Nanocrystalline Soft Magnetic Alloy

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Journal of Wuhan university of Technology(Materials Science) 2009年第5期24卷 747-749页

作者：华中 college of Physics Jilin Normal University

Fe68Zr20B12 amorphous alloy was prepared by mechanical alloying（MA） method and annealed at different temperatures. Microstructures and magnetic properties of Fe68Zr20B12 alloys as-milled and annealed at 693, 843, 943 and 993 K were studied. The raw powders（Fe, Zr, B） formed b. c. c. α-Fe solid solution at early stages of MA and then transformed into amorphous alloy. Grain size（D） of Fe68Zr20B12 alloys increases with increasing annealing temperature and keeps at nanometer level. The specific saturation magnetization（σs） increases with increasing annealing temperature from 300 K to 943 K, and then decreases with annealing temperature at 993 K because of the precipitation of Fe3B.

关键词： FeZrB amorphous-nanocrystalline alloy grain size specific saturation magnetization

Theoretical study on thermal decomposition of azoisobutyronitrile in ground state

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Science china chemistry 2004年第5期47卷 373-380页

作者： SUN Chengke1,2, ZHAO Hongmei1 & LI Zonghe1 1. Department of chemistry, Beijing normal university, Beijing 100875, china 2. Department of chemistry, Qujing normal college, Qujing 655000, china 1. Department of chemistry Beijing Normal University 100875 Beijing China 2. Department of chemistry Qujing Normal College 655000 Qujing China

The thermal decomposition mechanisms of azoisobutyronitrile (AIBN) in the ground state have been investigated systematically. Based on the potential energy surfaces (PES) of various possible dissociation paths obtained using the semiempirical AM1 method with partial optimization, the density function theory B3LYP/6-311G* method was employed to optimize the geometric parameters of the reactants, the intermediates, the products and the transition states, which were further confirmed by the vibrational analysis. The obtained results show that the re- action process of the two-bond (three-body) simultaneous cleavage Me2(CN)C─ N=N─ C(CN)Me2? 2Me2(CN)C?+N2 is much more favorable than the reaction process of the two one- bond asynchronous cleavage Me2(CN)CN=N─C(CN)Me2 ? Me2(CN)CN=N?+ Me2(CN)C?? Me2(CN)C?+ N2. It was suggested that the electron shrinking effect of double bond (─N=N─) in AIBN and the stabilities of the Me2(CN)C?radical as well as N2 molecule are main factors of leading to the reaction proceeding in the former pathway. The calculation results were consistent with all the experimental facts.

关键词： azoisobutyronitrile, radicals, thermal decomposition, density function theory (DFT).

Influence of MnO_2 on the photocatalytic activity of P-25 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 Sciences, Hebei normal university, Shijiazhuang 050016, china 2 college of Life Science, Hebei normal university, Shijiazhuang 050016, china college of chemistry and Material Sciences Hebej Normal UniversityShijiazhuang 050016China college of Life Science Hebei Normal UniversityShijiazhuang 050016China

Influences of α-MnO2, β-MnO2, and δ-MnO2 on the photocatalytic activity of Degussa P-25 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

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 normal university,Beijing 100875,china 2college of Life Science,Beijing normal 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

Effect of lead on survival, locomotion and sperm morphology of Asian earthworm, Pheretima guillelmi

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Journal of Environmental Sciences 2009年第5期21卷 691-695页

作者： ZHENG Rongquan, LI Canyang college of chemistry and Life Science, Zhejiang normal university, Jinhua 321004, china. [a]college of chemistry and Life Science Zhejiang Normal University Jinhua 321004 China

To provide basic toxicity data for formulating risk characterization benchmarks, the effects of lead on survival, locomotion, and sperm morphology were investigated in the Asian earthworm Pheretima guillelmi. The LC50 of P. guiUelmi for 7 and 14 d were 4285＋339 mg/kg and 3207＋248 mg/kg, which shows P. guillelmi can tolerate a higher concentration of lead nitrate. The average weight of the surviving earthworms decreased at concentration of 2800 mg Pb/kg soil, and the locomotor ability of earthworms exposed to a range of soil Pb concentrations showed a general decrease with increasing Pb concentrations. We also presented data depicting the sperm morphology of earthworms, which shows potential as a sensitive biomarker for measuring the effects of heavy metal on reproduction.

关键词： lead Pheretima guillelmi sperm morphology locomotion

Theoretical study of the mechanism for C-H bond activation in spin-forbidden reaction between Ti^+ and C_2H_4

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Science china chemistry 2009年第3期52卷 295-303页

作者： LV LingLing1, LIU XinWen1, YUAN Kun1, WANG XiaoFang1 & WANG YongCheng2 1 college of Life Science and chemistry, Tianshui normal university, Tianshui 741001, china 2 college of chemistry and Chemical Engineering, Northwest normal university, Lanzhou 730070, china college of Life Science and chemistry Tianshui Normal University Tianshui 741001 China college of chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China

The mechanism of the spin-forbidden reaction Ti+(4F, 3d24s1) + C2H4 → TiC2H2+ (2A2) + H2 on both doublet and quartet potential energy surfaces has been investigated at the B3LYP level of theory. Crossing points between the potential energy surfaces and the possible spin inversion process are discussed by means of spin-orbit coupling (SOC) calculations. The strength of the SOC between the low-lying quartet state and the doublet state is 59.3 cm-1 in the intermediate complex IM1-4B2. Thus, the changes of its spin multiplicity may occur from the quartet to the doublet surface to form IM1- 2A1, leading to a sig-nificant decrease in the barrier height on the quartet PES. After the insertion intermediate IM2, two dis-tinct reaction paths on the doublet PES have been found, i.e., a stepwise path and a concerted path. The latter is found to be the lowest energy path on the doublet PES to exothermic TiC2H2+ (2A2) + H2 products, with the active barrier of 4.52 kcal/mol. In other words, this reaction proceeds in the following way: Ti++C2H4 →4IC→IM1-4B2→4,2ISC→IM1- 2A1→[2TSins]→IM2→[2TSMCTS]→IM5→TiC2H2+(2A2)+H2.

关键词： Ti+(4F) and C2H4 spin-forbidden reaction mechanism spin-orbit coupling (SOC) concerted path

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, Tianjin normal university, 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

Arginine bi-directional translocation and breakdown into ornithine along the arbuscular mycorrhizal mycelium

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Science china(Life Sciences) 2009年第4期52卷 381-389页

作者： JIN HaiRu college of chemistry and Life Sciences, Zhejiang normal university, Jinhua 321004, china college of chemistry and Life Sciences Zhejiang Normal University Jinhua 321004 China

Bi-directional translocation and degradation of Arginine (Arg) along the arbuscular mycorrhizal (AM) fungal mycelium were testified through 15N and/or 13C isotopic labeling. In vitro mycorrhizas of Glomus intraradices and Ri T-DNA-transformed carrot roots were grown in dual compartment Petri dishes. [15N- and/or13C]Arg was supplied to either the fungal compartment or the mycorrhizal compartment or separate dishes containing the uncolonized roots. The levels and labeling of free amino acids (AAs) in the mycorrhizal roots and in the extraradical mycelia(ERM) were measured by gas chromatogra- phy/mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The ERM of AM fungi exposed in either NH4+ or urea as sole external nitrogen source had much higher 15N enrichment of Arg, compared with those in nitrate or exogenous Arg; however, glycerol supplied as an external car- bon source to the ERM had no significant effect on the level of Arg in the ERM. Meanwhile, Arg bio- synthesized in the ERM could be translocated intact to the mycorrhizal roots and thereby the level of Arg in the mycorrhizal roots increased to about 20% after culture of ERM in 4 mmol/L NH4+ for 6 weeks. Also Arg was found to be bi-directionally transported along the AM fungal mycelium through [U-13C]Arg labeling either in the mycorrhizal compartment or in the fungal compartment. Once Arg was translo- cated to the potential N-limited sites, it would be further degraded into ornithine (Orn) and urea since either [U-13C] or [U-15N/U-13C]Orn was apparently shown up in the mycorrhizal root tissues when [U-13C] or [U-15N/U-13C]Arg was labeled in the fungal compartment, respectively. Evidently Orn formation indi- cated the ongoing activities of Arg translocation and degradation through the urea cycle in AM fungal mycelium.

关键词： arbuscular mycorrhiza arginine in vitro culture 15N labeling ornithine urea cycle

Supramolecularly assembled water layers stabilized by sebacic anions in complexes of Zn(II) and Co(II)

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Science china chemistry 2010年第12期53卷 2539-2546页

作者： XIAN HuiDuo,LIU JianFeng & ZHAO GuoLiang Zhejiang Key Laboratory for Reactive chemistry on Solid Surfaces Institute of Physical chemistry,Zhejiang normal university college of chemistry and Life Science,Zhejiang normal university,Jinhua 321004,china 1. Zhejiang Key Laboratory for Reactive chemistry on Solid Surfaces Institute of Physical chemistry Zhejiang Normal University Jinhua 321004 China2. College of Chemistry and Life Science Zhejiang Normal University Jinhua 321004 China

Two three-dimensional supramolecular water architectures,[Zn(phen)3]2 ·[Zn(C10H16O4)·(H2O)3]·(C10H16O4)2·20H2O(1) and [Co(phen)3]2 ·[Co(H2O)6]·(C10H16O4)3·30H2O(2)[phen=1,10-Phenanthroline,C10H16O4=sebacic dianion],have been synthesized and characterized by IR,elemental analysis,thermogravimetric analysis,and single-crystal X-ray *** two structures both contain extensive hydrogen bonding between water molecules as well as between water molecules and sebacic *** water molecules and sebacic acid O atoms assembled 2D supramolecular corrugated sheets with different morphology in the two complexes.

关键词： Zn(II) Co(II) complex sebacic acid crystal structure supramolecular self-assemble water cluster