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Calculation of Thermodynamic Properties from Phase Diagram of the Pb-Zn System

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Journal of Materials Science & Technology 1997年第3期13卷 233-234页

作者： Zeng, WM ch.n, ny.qiu, gf Shanghai Institute of Metallurgy Chinese Academy of Sciences Shanghai 200050 China

The formulas for obtaining the interaction parameters of the liquid solution were first deduced from the immiscible phase diagram of binary system. Then, the relationships between activity coefficients and interaction parameters of the binary system were also deduced. Finally, thermodynamic properties of the Pb-Zn system were calculated by using these formulas.

关键词： Lead alloys

The Electrochemical Investigation of MEH-PPV in Ionic Liquid

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ch.nese chemical Letters 2000年第10期11卷 919-920页

作者： yang, ch He, gf Zheng, JR Qiao, J Li, yF ch.nese Acad Sci Inst Chem Ctr Mol Sci Lab Organ Solids Beijing 100080 Peoples R China

The electrochemical properties of MEH-PPV were: studied in ionic liquid([bmim](+)[PF6](-)) by cyclic voltammetry, chronoamperometry and AC impedance measurements. Both p- and n-doping of MEH-PPV were observed in the cyclic voltammograms, The chronoamperometric and AC impedance results indicate that the p-doping of MEH-PPV was controlled by the linear diffusion of counterions.

关键词： MEH-PPV electrochemistry ionic liquid

Lead-promoted Barbier-type reaction of aldehydes with propargyl bromides in aqueous media

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ch.nese Journal of chemistry 1997年第4期15卷 361-365页

作者： Zhou, Jy Sun, gf Zhang, MF Jia, y Wu, SH Department of chemistry Fudan University Shanghai 2004433 China

This paper reports that the reaction of the propargyl bromides with aldehydes promoted by powdered lead in aqueous media. The selectivity and possible mech.nism of these reactions are discussed. The yields of products for reaction of propargyl bromide are 31 similar to 71%. The ratios of allenyl alcohol and homopropargyl alcohol are 1:1.5 to 1:3. The product for reaction of phenyl propargyl bromide is allenyl alcohol and the yields are 52 similar to 84%.

关键词： lead reagent Barbier-type reaction propargyl bromides aqueous media

Comparative Molecular Field Analysis on a Set of new Herbicidal Sulfonylurea Compounds

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ch.nese chemical Letters 1997年第6期8卷 503-504页

作者： Liu, J Wang, X Ma, y Li, ZM Lai, CM Jia, gf Wang, LX nAnKAI UnIV STATE LAB ELEMENTOORGAN CHEMELEMENTOORGAN CHEM INSTTIANJIN 300071PEOPLES R CHINA

In this paper Comparative Molecular Field Analysis (CoMFA) method was applied to study the three-dimensional quantitative structure activity relationship (3D-QSAR) on a set of new herbicidal sulfonylureas. We optimize... 详细信息

关键词： Comparative Molecular Field Analysis on a Set of new Herbicidal Sulfonylurea Compounds

Studies on the reaction of 3-substituted-4-hydroxy-2H-1,2-benzothiazine 1,1-dioxides with aryl isocyanates and the synthesis of corresponding derivatives

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ch.nese Journal of chemistry 1996年第5期14卷 467-471页

作者： Zhao, gf yang, HZ nAnKAI UnIV NATL KEY LAB ELEMENTOOGAN CHEMINST ELEMENTOORGAN CHEMTIANJIN 300071PEOPLES R CHINA

The reaction of 3-substituted-4-hydroxy-2H-1,2-benzothiazine 1,1-dioxides with aryl isocyanate under different equivalents of strong base naH was studied. Seventeen of new derivatives were obtained whose structures we... 详细信息

关键词： benzothiazine dioxides reaction aryl isocyanate synthesis

RELATIOnS BETWEEn TWO SETS OF FUnCTIOnS DEFInEDBy THE TWO InTERRELATED OnE-SIDE LIPSchITZCOnDITIOnS

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Journal of Computational Mathematics 1999年第5期17卷 457-462页

作者： Zhao, SS Wang, Cy Zhang, gf Lanzhou Univ Dept Math Lanzhou 730000 Peoples R China Dept Commun Commun Ctr Lanzhou 730030 Gansu Province Peoples R China

In the theoretical study of numerical solution of stiff ODEs, it usually assumes that the righthand function f(y) satisfy one-side Lipschitz condition less than or equal to v(1)parallel to y - z parallel to(2),f : Ome... 详细信息

In the theoretical study of numerical solution of stiff ODEs, it usually assumes that the righthand function f(y) satisfy one-side Lipschitz condition y) - f(z),y - z >less than or equal to v(1)parallel to y - z parallel to(2),f : Omega subset of or equal to C-m --> C-m, or another related one-side Lipschitz condition [F(y) - F(Z), y - Z](D) less than or equal to v'parallel to y - Z parallel to(D)(2), F : Omega(s) subset of or equal to C-ms --> C-ms, this paper demonstrates that the difference of the two sets of all functions satisfying the above two conditions respectively is at most that v' - v' only is constant independent of stiffness of function f.

关键词： stiff ODEs one-side Lipschitz condition logarithmic norm

A Review of Density Holes Upstream of Earth＇s Bow Shock

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空间科学学报 2011年第6期31卷 693-704页

作者： G K Parks E Lee n Lin J B cao S y Fu J K Shi Space Sciences Laboratory University of California Berkeley USA Kyung Hee University Suwon Korea School of Astronautics Beihang University Beijing 100191 Institute for Space Physics Peking University Beijing 100871 State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190

Larmor size transient structures with density depletions as large as 99%of ambient solar wind density levels occur commonly upstream of Earth’s collisionless bow *** "density holes" have a mean duration of 17.9±10.4s but holes as short as 4 s have been *** average fractional density depletion（δn/n） inside the holes is 0.68±*** density of the upstream edge moving in the sunward direction can be enhanced by five or more times the solar wind density. Particle distributions show the steepened edge can behave like a shock,and measured local field geometries and Mach.number support this *** shaped magnetic holes accompany the density holes indicating strong coupling between fields and *** densities as large as 150nA·m-2 are observed at the leading compressed *** waves are elliptically polarized and rotating in the sense of ions（left hand） in the plasma *** waves appear to grow and steepen as the density holes convect with the solar wind toward the *** transient nature of density holes suggests that the temporal features could represent the different stages of nonlinear evolutionary processes that produce a shock-like *** density holes are only observed with upstream particles,suggesting that back-streaming particles interacting with the solar wind are important. The significance of these observations is still being investigated.

关键词：大密度上游地球激波审查平均时间几何形状大电流密度

Linear operators preserving idempotence on matrices spaces over skew-fields

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ch.nese Science Bulletin 1997年第15期42卷 1244-1247页

作者： Liu, SW yuan, gf Department of Mathematics Heilongjiang University Harbin China

LET R and R1 be skew-fields with centres F and F1, where F F1 and |F|>2. By Mn （R）and In（R） we denote the F-space of all n×n matrices over R and the set of all idempotentmatrices in Mn（R）, respectively. If a linear map L from Mn（R） to Mm（R1） satisfies L（In（R）） Im（R1） we call L an idempotence preserver （all such maps will be denoted byLn, m（R,R1））. To determine the forms of idempotence preservers is one important

关键词： skew-field idempotence linear operator.

Synthesis of 5,7-Dimethyl-2-(5-Substituted-1,3,4-Oxadiazole-2-yl)- Methylenethio-1,2,4-Triazolo[1,5-a]Pyrimidines as Potential Fungicides

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ch.nese chemical Letters 2001年第10期12卷 877-880页

作者： yang, gf Liu, ZM Qing, XH Cent ch.na normal Univ Inst Pesticide Chem Wuhan 430079 Peoples R China

A series of diheterocyclic compounds containing 1,2,4-triazolo [1,5-a]pyrimidine and 1, 3,4-oxadiazole were designed and synthesized starting from 2-mercapto-5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine. The structure of all compounds prepared were confirmed by H-1 nMR spectroscopy and elemental analysis. The preliminary bioassay indicated that the title compounds displayed good fungicidal activity against Rhizoctonia solani.

关键词： 1,2,4-triazolo[1,5-a]pyrimidine 1,3,4-oxadiazole diheterocyclic compounds synthesis fungicides