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STRUCTURE　OF　6-EPICHASMANINE

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Chinese Chemical Letters 1996年第5期7卷 443-444页

作者： Li, zb Wang, FP W CHINA UNIV MED SCI SCH PHARMDEPT CHEM & MED NAT PRODCHENGDU 610044PEOPLES R CHINA

Abstract: A new norditerpenoid alkaloid, 6-epichasmanine, was isolated from the roots of Aconitum kusnezoffii. Its structure was determind on the basis of spectrscopic analysis.

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Synthesis of 2-Methylenesuccinimides Modified by Germatranes

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Chinese Chemical Letters 1996年第11期7卷 989-990页

作者： Zhang, zb Chen, RY NANKAI UNIV INST ELEMENTOORGAN CHEMTIANJIN 300071PEOPLES R CHINA

A series of 2-methylenesuccinimides modified by germatranes were synthesized br two methods. The structures of products were confirmed by (1)HNMR, IR elemental analysis, and X-ray diffraction.

关键词： Synthesis of 2-Methylenesuccinimides Modified by Germatranes

AN ENDOCHRONIC CONSTITUTIVE MODEL FOR RATE-DEPENDENT AND NONPROPORTIONAL CYCLIC PLASTICITY

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Acta Mechanica Solida Sinica 1998年第4期11卷 295-306页

作者： Zhao, SX Kuang, zb Huaqiao Univ Dept Civil Engn Quanzhou 362011 Peoples R China Shanghai Jiao Tong Univ Dept Engn Mech Shanghai 200240 Peoples R China

The total stress response of material is decomposed into a sum of an equilibrium stress response and a non-equilibrium overstress response. Correspondingly, the rate-independent intrinsic time and the rate-dependent intrinsic time are defined respectively. Additional hardening functions for describing the isotropic and anisotropic nonproportional effects are assumed to be related to the accumulation of plastic strain component along the normal of equilibrium stress trajectory, in which the effects of geometry of the loading path are included. An endochronic constitutive model for rate-dependent, nonproportional cyclic plasticity is formulated and applied to simulate the stress responses of stainless steel XCrNil8. 9 for some typical loading programs at different loading rates. A comparison between predicted results and experimental ones by Haupt and Lion shows that the former are in agreement with the latter.

关键词： nonproportional loading rate-dependence overstress endochronic constitutive equations

INTERFACE CRACK IN BIPIEZOTHERMOELASTIC MEDIA

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Acta Mechanica Solida Sinica 1996年第1期9卷 13-26页

作者： Shen, SP Kuang, zb XIAN JIAOTONG UNIV DEPT MECH ENGNXIAN 710049PEOPLES R CHINA

By using the extended version of Eshelby-Stroh's formulation and the method of analytical continuation, the problems of interface cracks are reduced to a Hilbert problem of vector form. A general explicit closed form solution for the piezothermoelastic interface crack problem is then obtained, the whole field solutions of temperature, heat flux, displacements, electric field, stress and electric induction are given, the explicit expressions for the crack opening displacements and electric potential are also provided.

关键词： piezothermoelastic interface crack heat

Comparison study on water use efficiency of wheat flag leaf

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Chinese Science Bulletin 1998年第14期43卷 1205-1211页

作者： Zhang, zb Shan, L Chinese Acad Sci Inst Soil & Water Conservat State Key Lab Soil Eros & Dryland Farming Loess P Yangling 712100 Peoples R China

wild species and cultivars were planted under irrigated and dryland field condition. LCA\|3 model photosynthesis apparatus was employed to measure flag leaf WUE. The results show that WUE of diploid and tetraploid increases as the wild species became cultivated species. WUE of flag leaf increases as the chromosome ploid increases (2\%n\%→4\%n\%→6\%n\%) in the wheat evolution. Among modern cultivars, WUE of most irrigated varieties is higher than that of dryland varieties.

关键词： wheat flag leaf water use efficiency.

Synthesis and Luminescence Properties of Barium Fluorotungstate Phosphors

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Chinese Chemical Letters 1997年第7期8卷 643-644页

作者： Yang, SJ Sun, JT Qin, zb HUBEI NORMAL UNIV DEPT CHEMHUNGSHI 435002PEOPLES R CHINA WUHAN UNIV DEPT CHEMWUHAN 430072PEOPLES R CHINA

The investigation of the system BaF2-WO3 revealed the existence of a fluoro-tungstate formulated as Ba2WO3F4. The Ba2WO3F4 was prepared with the solid state reaction method. Under UV or X-ray excitation, Ba2WO3F4 exhibits a very strong blue-green emission peaking at 480 nm at room temperature. The luminescence properties are similar to those of the tungstate, especially MgWO4. The luminescence and energy transfer of tungstates are well known for a long time and was reviewed by Blasse([1]). But barium tungstate show only weak luminescence even down to liquid helium temperature([2]). We were surprised to find that Ba2WO3F4 is an efficient phosphor which can be practically used. In this paper, the preparation method and luminescence properties of Ba2WO3F4 phosphor were investigated. The relationship between the luminescent properties and crystal structure was discussed.

关键词： Ba nm

CAPILLARY　ELECTROPHORESIS　DETERMINATION　OF　INOSINE　IN　SOMEDRUG　FORMULAE　USING　HYPOXANTHINE　AS　INTERNAL　STANDARD

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Chinese Chemical Letters 1995年第8期6卷 701-704页

作者： Chen, Y Yuan, zb Acad Sinica USTC Grad Sch Beijing 100039 Peoples R China

A new rapid and accurate method for determining inosine by capillary zone electrophoresis(CZE) is presented. The electrophoresis separation was performed at 24℃ in a fused-silica capillary(51.2cm×50 μmi.d., 38.5cm to UV detector)using 20mmol/L borax-20mmol/L H3PO4(pH 8.5) as the background electrolyte at 24KV applied voltage. Inosine samples were led into the capillary electrokinetically at 10KV for 15 seconds. In the range of 20μg/mL to 300μg/mL, inosine can be quantitatively determined with a deduction limit of 2.1μg/mL and a RSD of 2.92%. Hypoxanthine was used as the internal standard.

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Photoinitiated Reaction of β-Bromonaphthalene with Pinacolone Ion in DMSO

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Chinese Chemical Letters 2000年第11期11卷 945-948页

作者： Chen, zb Zhao, LY Zhang, Z Univ Shanxi Dept Chem Taiyuan 030006 Shanxi Peoples R China

The photoinitiated reaction of beta -bromonaphthalene with excess pinacolone enolate does not yield expected normal S(RN)1 product 1-beta -naphthyl-3,3-dimethyl-2-butanone, 3, but a more complex molecule 2.2-dimethyl-5-(1',1'-dimethylethyl)-6-beta -naphthyl-5-hexene-3-one, 4, deriving from it. The reaction is inhibited by m-dinitrobenzene and do not occur in the absence of light. Structure analysis of the product, along with other evidence, indicates a mechanism for this reaction, where addition of a further pinacolone molecule to carbonyl group of 3 and subsequent elimination of a water molecule would afford product 4, once the S(RN)1 substitution product 3 has formed.

关键词： Photoinitiated Reaction of MS Bromonaphthalene with Pinacolone Ion in DMSO

Asymmetric Meerwein-Ponndorf-Verley reduction catalyzed by a new type of chiral binaphthol-samarium complex

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Chinese Journal of Chemistry 1996年第6期14卷 561-564页

作者： Ding, zb Cheng, KJ Wu, SH FUDAN UNIV DEPT CHEMSHANGHAI 200433PEOPLES R CHINA

A new type of chiral 1,1'-binaphthol(BINOL) derived samarium complex, prepared from (R)- or (S)-BINOL and SmCl3, serves as an enantioselective catalyst for the Meerwein-Ponndorf-Verley (MPV) reduction in the presence of Molecular Sieves 4 Angstrom(MS 4 Angstrom). Moderate enantioselectivity was obtained. Kinetic studies show slight decrease of the enantiomeric excess with the conversion.

关键词： asymmetric synthesis reduction samarium reagent