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Rare Metals 2010年第5期29卷 473-479页

作者： LIU Yang,FU Yanqiang,JIN Chuan,and FENG Chun department of Materials Physics and chemistry,university of science and Technology Beijing,Beijing 100083,china department of Materials Physics and chemistry University of Science and Technology Beijing Beijing China

The exchange coupling at the ferromagnetic/antiferromagnetic （FM/AFM） interface is influenced by both the magnetic structure and the crystalline micro-structure. Co/FeMn/Co thin films with 0.4 nm Pt spacer layer inserted into the Co/FeMn and FeMn/Co interface respectively were deposited by means of magnetron sputtering. The two interfaces upon and beneath the FeMn layer show distinct behaviors before and after the Pt spacer inserted. There is a remarkable shrink of the interracial uncompensated spins within the FeMn bottom interracial monolayers, whereas a relaxation of the pinning strength of the FeMn interfacial spins along the out-of-plane direction occurs at the top in- terface. XRD analysis indicates the Pt layer upon the FeMn layer forms an fcc （002） texture, implying the magnetic discrepancy between the top and bottom FeMn interfaces has crystalline structural origins.

关键词： interfaces exchange coupling exchange bias spacer stress anisotropy lattice match

Mixed-valence copper coordination polymers based on CuSCN or CuN_(3) as bridging motifs

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science china chemistry 2005年第Z1期48卷 41-44页

作者： FAN Guang,GAO Shengli,CHEN Sanping,ZENG Minghua & XIE Gang department of chemistry,Northwest university,Xi’an 710069,china department of chemistry,Guangxi Normal university,Guilin 541000,china department of chemistry Northwest University Xi’an China department of chemistry Guangxi Normal University Guilin China

Two novel mixed valence copper coordination polymers, [Cu(2-pac)2(CuN3)(H2O)]n (1) and [Cu(2-pac)2(CuSCN)2]n (2), have been prepared through hydrothermal synthesis and analyzed for structure determination, which exhibit two- and three-dimensional structures respectively. In complex (1), zigzag chains of [CuN3]n running parallel to the c direction are interconnected by Cu(2pac)2 to form a two-dimensional layer structure. In complex (2), the arrangement of μ-1,1,3 bridging thiocyanate ligand leads to the formation of ten-membered Cu-SCN- Cu-S-Cu-NCS rings, and each Cu atom is further linked by Cu(2-pac)2 to afford a three-dimensional configuration.

关键词： hydrothermal synthesis, crystal structure, 2-pyrazinecarboxylic acid, coordination polymer.

Physical and Electrochemical Properties of Acid 1-Methyl-3-Ethylimidazolium Chloride/AlCl_3/LiAlCl_4 Molten Salt

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 286-291页

作者： Ying Sing Fung, Ruqi Zhou ( department of chemistry, The university of Hong Kong, Hong Kong, china department of Inorganic and Non-metal Materials, university of science and Technology Beijing, Beijing 100083, china) department of chemistry University of Hong Kong Hong Kong Hong Kong department of Inorganic and Non-metal Materials University of Science and Technology Beijing Beijing 100083 China

An acid molten salt was formed by means of mixing 1 -methyl- 3 -ethylimidazolium chloride with AlCl3 and LiAlCl4 at ambient temperature. The solubility of LiAlCl4 in the acid molten salt was measured. Variations of specific conductivity, density and kinetic viscosity of molten salt with mole ratio o f MeEtlmCl/A1lCl3/LiAlCl4 were observed. A solubility maximum of LiAlCl4 with 5 4% in molar fraction was shown at a mole ratio of AlCl43/MeEtlmCl = 1 .2. An increase in density and viscosity, and a decrease in specific conductivity were found with increasing the concentrations of LiAlCl4 and AlCl3. The dependence of specific conductivity of this acid molten salt upon temperature was found to display Vogel-Tammanm-Fucher behavior. However, Arrhenius behavior was observed at two special mole ratios of MeEtImCl/AlCl3/LiAlCl4 = 1:1.5:0.05 and 1. 1.5:0. 10. The conductivity equations of this molten salt at various compositions were constructed. The ion interaction in the acid molten salt was studied using 7Li and 27Al nuclear magnetic resonance spectroscopic methods. The effect of concentrations of LiAlCl4 and AlCl3 on the ion interaction was also discussed.

关键词： Li-7 NMR Al-27 NMR room temperature molten salt aluminum chloride lithium tetrachloroaluminate physical property electrochemical property Materials

Approach to synthesis of novel chiral 3-chloro-2(5H)- furanone and its application in asymmetric reactions

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Chinese science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. department of chemistry, Tonghua Teacher’s college, Tonghua 134002, china 2. department of chemistry, Beijing Normal university, Beijing 100875, china department of chemistry Tonghua Teacher’s College Tonghua China department of chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2,3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3-chloro-2-(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.

THE VISCOELASTIC EFFECT ON THE FORMATION OF MESO-GLOBULAR PHASE OF DILUTE HETEROPOLYMER SOLUTIONS

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Chinese Journal of Polymer science 2003年第2期21卷 117-122页

作者： Chi Wu The Open Laboratory of Bond Selective chemistry department of Chemical Physics, university of science and Technology of china, Hefei 230026 china department of chemistry The Chinese university of Hong Kong Shatin, Hong Kong university of science and Technology of china Laboratory of Bond Selective Chemistry CAS Hefei 230026

Linear homopolymer chains in poor solvent exist either as individual crumpled single chain globules or asmacroscopic precipitate, depending on whether the solution is in the one- or the two-phase region. However, linearheteropolymer chains in dilute solution might be able to form stable mesoglobules made up of a limited number of chains ifthe degree of amphiphilicity of the chain is sufficiently high and the experimental conditions are appropriate. The self-assembly of block copolymers in a selective solvent is typical of such examples. In practice, the formation of stablemesoglobules can be directly related to the formation of novel polymeric nanopaticles in solution. In this article, we willaddress the formaton of mesoglobular phase not only on the basis of thermodynamics, but also from a kinetic point of view,which leads to the discussion of how viscoelasticity can affect the phase behavior of heteropolymer chains in dilute *** formation and stabilization of several different kinds of novel polymeric nanopedicles will be used to illustrate ourdiscussion.

关键词： Viscoelasticity Mesoglobular phase Heteropolymer Nanoparticle Polymer Dispersion Microphase inversion

Surface Tension Calculation of Undercooled Alloys

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Rare Metals 2001年第1期20卷 58-61页

作者： Zhiyu Qiao, Lijun Yan, Zhanmin Cao, Guirong Liu (department of Physical chemistry, university of science and Technology Beijing, Beijing 100083, china) 北京科技大学北京 100083

Based on the Butler equation and extrapolated thermodynamic data of undercooled alloys from those of liquid stable alloys, a method for surface tension calculation of undercooled alloys is proposed. The surface tensions of liquid stable and undercooled Ni-Cu (x(Ni)=0.42) and Ni-Fe (x(Ni)=0.3 and 0.7) alloys are calculated using STCBE (Surface Tension Calculation based on Butler Equation) program. The agreement between calculated values and experimental data is good enough, and the temperature dependence of the surface tension can be reasonable down to 150-200 K under the liquid temperature of the alloys.

关键词： undercooled alloy surface tension Butler equation

Catalytic Asymmetric Cyclopropanation using a New Chiral β-Diketone Cu (Ⅱ) Complex as a Catalyst

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Chinese Chemical Letters 1998年第7期9卷 607-608页

作者： Yu XU Zhong Yi WANG and Tian Pa YOU(department of chemistry, university of science and Technology of china, Hefei 230026) department of chemistry Univ. of Sci./Technology of China Hefei 230026 China

A new chiral β-diketone Cu (Ⅱ) catalyst was synthesized and used for the asymmetric cyclopropanation of styrene with diazoester. A high optical yield (~90%) was achieved. The effect of the structure of substrate on the enantioselectivity was studied. Both chendcal yield and optical yield being reduced when the steric bulky substrate was employed. The reaction mechanism and the chiral model of the transition state are under fufther investigation.

关键词： Asymmetric cyclopropanation β-Diketone Cu (Ⅱ) Complex

The Cobordism Classification of Involution on DOLD Manifold P(1,2l)

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Acta Mathematica Sinica,English Series 1997年第1期13卷 9-20页

作者： Wu Zhende Liu Zongze (department of Mathematics,hebei Normal university,Shijazhuang 050016,china)Bai Ruipu (department of Mathematics,hebei university,baoding 071002,china) department of Mathematics Hebei Normal University 050016 Shijazhuang China

Supposing the smooth involution of the DOLD manifold P(2,2l)satisfies the following condition:the fiberation π:P(1,2l)×T_×(-1)S~∞→RP(∞)is totally nonhomologous to zero(cf.[1, p373]),this paper determines the cla... 详细信息

关键词： Stiefel-Whitney class Involution on smooth manifold Bordism class Wu formulas

Trace metals distribution in synodontis membranaceus, sediments, Asystasia Gangetica and Platostoma Africanium from Ofuafor River around Delta Glass Factory in Ughelli North Local Government Area, Delta State Nigeria

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Journal of environmental sciences 2002年第1期14卷 79-82页

作者： NWAJEI, G.E. (Faculty of science, department of chemistry, Delta State university, Abraka, Nigeria) Faculty of science Department of Chemistry Delta State University 尼日利亚 Abraka

The trace metals analysis in synodontis membranaceus (head and tail), bottom sediments, Asystasia Gangetica and Platostoma Africanium were carried out using atomic absorption spectrometer of model Perkin Elmer 3110. Metals analysed were copper, nickel, mangenese, chromium, iron lead and cobalt. These metals were detected in the above samples. Vegetation samples concentration in copper, manganese, chromium, iron and cobalt were higher than those obtained in bottom sediments. The tail part of the fish contents of trace metals were also higher than those of the head. The results obtained in this work exceeded the results of water analysis carried out by Omoregha on the same river. Metals such as copper, nickel, manganese and chromium were below detection limit in the water from the same river. The bioaccumulation of these trace metals in these samples were traced to activities of Delta Glass Factory.

关键词： trace metals Ofuafor River bioaccumulation of metals contamination industrial effluents Delta Glass Factory

Synthesis of 6-aryl substituted 3-(5'-phenyl-2H-tetrazole-2'-methylene)-S-triazolo[3,4-b]-1,3,4-thiadiazoles

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Chinese Journal of chemistry 1995年第5期13卷 448-453页

作者： ZHANG, Zi-Yi ZOU, NingNational Laboratory of Applied Organic chemistry, department of chemistry, Lanzhou university, Lanzhou, Gansu 730000, china National Laboratory of Applied Organic chemistry Department of Chemistry Lanzhou University Lanzhou Gansu 7S0000 China

In this paper , 10 novel 6-aryl-3-(5'-phenyl-2H-tetrazole-2'-methylene)-S-triazolo[3, 4-b]-1,3,4-thiadiazoles have been synthesized by the condensation of 3-(5'-phenyl-2H-tetrazole-2'-methylene)-4-amino-5-mercapto-1,2,4-triazole with various aromatic carboxylic acids in the presence of phosphorus oxychloride. The structure of these compounds was determined by elemental analysis , UV, IR, 1H NMR and MS. Their spectral properties were also discussed.

关键词： S-triazolo[3,4-b]-1,3,4-thiadiazole synthesis spectral analysis