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Journal of Materials Science & Technology 2000年第1期16卷 55-58页

作者： Cao, FR cui, jz Wen, JL Lei, F Northeastern Univ Sch Met & Mat Dept Mat & Forming Control Shenyang 110006 Peoples R China

Mechanical properties and microstructure evolution of Mg-8.4 wt pet Li alloy have been investigated. The superplastic elongation-to-failure 920% at 573 K and initial strain rate of 5 x 10(-4) s(-1) at low nominal stress 2 MPa has been demonstrated. It was shown through optical microstructure that the average grain sizes at gauge length section before and after superplastic tension and at grip section were 7.5 mu m, 31.7 mu m and 20 mu m respectively, indicating significant deformation induced grain growth and static grain growth. Comparison of experiment data with published data for superplastic Mg-Li alloys shows that fine grain size and about 50 to 50 phase ratio contribute to achieving the largest superplasticity. Some related research works in other alloys are compiled and further evidences to such theoretic argument are provided.

关键词： Magnesium alloys

Fractals in Steel-Aluminum Solid to Liquid Bonding

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Journal of Materials Science & Technology 1999年第5期15卷 486-488页

作者： Zhang, P Du, YH Ren, XP Ba, LM Liu, HW cui, jz Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Anshan Automobile Fittings Factory Anshan 114014 Peoples R China Northeastern Univ Met Forming Dept Shenyang 110006 Peoples R China

This paper studied the fractal characteristic of the interfacial shear surface of steel-Al solid to liquid bonding plate, and determined the relationship between fractal dimension and interfacial shear strength. The research results showed that the relationship between fractal dimension and interfacial shear strength could be described as y=26.2x+4.2 (where y was interfacial shear strength, x was fractal dimension) and when 08Al steel plate was coarsened by steel wire wheel which was made up with steel wires whose diameter were 1.4 similar to 1.6 mm, the optimum coarsening pattern of the steel plate surface could be got, the corresponding maximum interfacial shear surface fractal dimension of the bonding plate was 2.33, and the maximum interfacial shear strength of the bonding plate was 65.3 MPa.

关键词： Nature MPa

DYNAMICS OF A ROTATING FLEXIBLE MANIPULATOR WITH TIP LOAD

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Acta Mechanica Solida Sinica 1998年第4期11卷 365-373页

作者： Hu, ZD Hong, jz Shanghai Jiao Tong Univ Dept Engn Mech Shanghai 200030 Peoples R China

The dynamics of a flexible manipulator is investigated in this paper. From the point of view of dynamic balance, the motion equations of a rotating beam with tip load are established by us ing Hamilton' s principle. By taking into account the effects of dynamic stiffening and dynamic softening, the stability of the system is proved by employing Lyapunov' s approach. Furthermore, the method of power series is proposed to find the exact solution of the eigenvalue problem The effects of rotating speed and tip load on the vibration behavior of the flexible manipulator are shown in numerical results.

关键词： flexible manipulator large rigid motion dynamic stiffening stability of System Lyapunov functional eigenvalue problem

QNQL processes-- (H, Q)-processes and their applications

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Chinese Science Bulletin 1997年第11期42卷 881-886页

作者： Hou, ZT Liu, ZM Zou, jz Research Department Changsha Railway University Changsha China

As we know,many scholars have been involved in the study of stochastic processes,whichhave a wide range of applications,such as the Markov *** the study of Markov pro-cesses,minimal Markov chain(*** minimal homogeneou... 详细信息

关键词： QNQL process (H Q)-process the backward equation the forward equation.

THE COUPLING DYNAMICAL MODELING THEORY OF FLEXIBLE MULTIBODY SYSTEM

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Acta Mechanica Solida Sinica 1999年第4期12卷 365-372页

作者： Jiang, LZ Hong, jz Chansha Railway Univ Coll Civil & Architecture Engn Changsha 410075 Peoples R China Shanghai Jiao Tong Univ Dept Engn Mech Shanghai 200030 Peoples R China

Based on the deformation theory of elastic beams, the coupling effect between the coupling displacements of a point on the middle line of beam and large overall motion is presented. The 'coupling matrix library' and Jourdain's variation principle and single direction recursive formulation method are used to establish the general coupling dynamical equations of flexible multibody system. Two typical examples show the coupling effect between coupling displacements and large overall motion on the dynamics of flexible multibody system consisting of beams.

关键词： coupling displacement coupling dynamical modeling theory large overall motion single direction recursive formulation flexible multibody system

Synthesis, luminescence properties and energy transfer of binary and ternary rare earth complexes with aromatic acids and 1,10-phenanthroline

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Chinese Journal of Chemistry 1997年第3期15卷 242-249页

作者： Yan, B Zhang, HJ Ni, jz Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

A series of binary and ternary rare earth (Gd, Eu, Tb) complexes with ortho hydroxyl benzoic acid, pam aminobenzoic acid, nicotinic acid and 1,10-phenanthroline were synthesized. Phosphorescence spectra and lifetimes of Gd complexes were measured and the lowest triplet state energies of gadolinium binary complexes end the intramolecular energy transfer efficiencies were determined. The luminescence properties and energy transfer process of Eu3+ and Tb3+ complexes were discussed.

关键词： luminescence energy transfer rare earth complexes energy match

Experimental studies on generation kinetics of n-alkanes in petroleum

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Chinese Science Bulletin 1997年第12期42卷 1020-1023页

作者： Liu, jz Tang, YC Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Chevron Petrdeum Technology Company La Habra USA

SINCE normal alkanes are the most important components in crude oil,the research on genera-tion kinetics for normal alkanes is very important for understanding the mechanisms of petroleum ***,due to complicated mechanism of n-alkane generation andlack of efficient analytical methods,so far there are few reports in this *** overcome

关键词： organic geochemistry n-alkane activation energy pyrolysis.

The Synthesis, Luminescence and Energy Transfer of the Binary and Ternary Complexes of Rare Earth with Aminobenzoic Acids and 1,10-Phenanthroline

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Chinese Chemical Letters 1997年第4期8卷 353-356页

作者： Yan, B Zhang, HJ Ni, jz CHINESE ACAD SCI CHANGCHUN INST APPL CHEMLAB RARE EARTH CHEMCHANGCHUN 130022PEOPLES R CHINA

Thirteen kinds of binary and ternary complexes of rare earth (Gd, Eu,Tb) with ortho (para) aminobenzoic acid and 1.10--phenanthroline were synthesized and characterized. The phosphorescence spectra and lifetimes of gadolinium complexes were measured and the lowest triplet state energies of ligands and the energy transfer efficiencies between ligands were determined. The luminescence properties and intramolecular energy transfer of these complexes were studied in details.

关键词： ABA Luminescence and Energy Transfer of the Binary and Ternary Complexes of Rare Earth with Aminobenzoic Acids and 1,10-Phenanthroline The Synthesis

Interface Characterization of the SiCp/Al Composites Made by Powder Metallurgy

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Journal of Materials Science & Technology 1999年第2期15卷 147-150页

作者： Fan, jz Zhang, K Shi, LK Zhang, SM Gen Res Inst NonFerrous Met Beijing 100088 Peoples R China

The interface of the SiCp/Al composites produced by powder metallurgy processing involving hot-pressing above the matrix solidus temperature has been investigated by means of TEM. Several kinds of interfaces between the reinforcements and the matrix in the composite, including the clean interfaces, the faceted interfaces and the slight reaction interfaces, are presented. And most of interfaces belong to the slight reaction interfaces which are composed of the Al with different orientation from the Al matrix near the interface zone and particle-like substances produced by MgAl2O4 spinels and impurities.

关键词： Metallic matrix composites

Long-range Correlations in Iodide Cluster Aggregates

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Journal of Materials Science & Technology 1997年第4期13卷 271-273页

作者： Zhang, jz Yang, XD Li, HD Ye, XY TSING HUA UNIV DEPT CHEMBEIJING 100084PEOPLES R CHINA

The morphology of tin iodide deposits grown during gas-solid transformation demonstrated long-range correlations. These iodide deposits include basically two kinds of forms: fractal structure and dendritic-like structure. The fractal structure was a sort of tin iodide cluster aggregation. Each fractal structure was composed of numerous tin iodide clusters that connected or disconnected with each other. The average size of fractal structures is between 10 and 22 mu m. The dendritic-like structure was also composed of many tin iodide clusters. These clusters aggregated and formed a dendritic pattern.

关键词： Iodine compounds