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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

基于静力推覆分析的穿越地裂缝浅埋地铁车站地震破坏模式研究

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振动与冲击 2024年第1期43卷 54-63,70页

作者：熊仲明陈帜陈轩郑坤阿鑫西安建筑科技大学土木工程学院西安710055 陕西省岩土与地下空间工程重点实验室西安710055 青海省建筑建材科学研究院有限责任公司西宁810008 青海省高原绿色建筑与生态社区重点实验室西宁810008

以处于西安f4地裂缝场地的浅埋地铁车站为研究对象,通过开展振动台试验,探讨了地裂缝场地和结构的震害特征。同时,考虑场地地震响应的非一致性,采用静力推覆分析方法,分析了穿越地裂缝浅埋地铁车站的地震破坏模式。结果表明:针对地裂缝... 详细信息

以处于西安f4地裂缝场地的浅埋地铁车站为研究对象,通过开展振动台试验,探讨了地裂缝场地和结构的震害特征。同时,考虑场地地震响应的非一致性,采用静力推覆分析方法,分析了穿越地裂缝浅埋地铁车站的地震破坏模式。结果表明:针对地裂缝场地地下结构的Pushover分析方法能够较真实地反应地震作用下地裂缝场地的活动特征和地下结构的破坏特点。在水平地震作用下,趋于稳定状态的地裂缝上、下盘土体主要进行张合活动(相互挤压与分离)。其中,相互挤压会对结构中柱施加明显附加压弯作用。地裂缝场地土体的水平剪切变形是结构破坏的主要外在因素,而地裂缝活动造成的附加压弯作用会进一步增大中柱轴压比,降低中柱的变形能力,加速结构的地震破坏。在地裂缝场地特征变形作用下,结构底层中柱水平剪切变形能力相对较弱,且结构剪力表现出明显的空间分布规律,上盘结构底层中柱是结构的抗震关键构件。研究结果对该类结构的抗震设计具有重要参考价值。

关键词：地裂缝地铁车站静力推覆分析破坏模式

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.

All-optical driven soft crawler with complexmotion capabilities

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International Journal of Smart and Nano Materials 2024年第2期15卷 348-364页

作者： chenchu Zhang Jin Wang Linhan Zhao Renfei chen Qiangqiang Zhao Jie Zhao Fating Liu Yucheng Bian Heng Zhang Yisen Wang Chaowei Wang Ying Hu Anhui Province Key Lab of Aerospace Structural Parts Forming Technology and Equipment Institute of Industry and Equipment TechnologyHefei University of TechnologyHefeiChina CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefeiChina GBA Branch of Aerospace Information Research Institute Chinese Academy of SciencesGuangzhouChina

The emergence of millimeter-scale soft actuators has signifi-cantly expanded the potential applications in areas such as search and rescue,drug delivery,and human assistance,due to their high *** these advancements,achieving precise control over the intricate movements of soft crawlers poses a significant *** this study,we have developed an all-optical approach that enables manipulation of propul-sive forces by simultaneously modifying the magnitude and direction of friction forces,thereby enabling complex motions of soft ***,the approach is not constrained by specific actuator shapes,and theoretically,any elongated photothermal actuator can be *** actuator was designed with an isosceles trapezoid shape,featuring a top width of 2mm,a bottom width of 4 mm,and a length of 8 *** our,manipulation approach,we showcase a proof-of-concept for complex soft robotic motions,including crawling(achieving speeds of up to 2.25 body lengths per minute),turning,avoiding obstacles,handling and trans-ferring objects approximately twice its own weight,and navi-gating narrow spaces along programmed *** results showcasethis all-optical manipulationapproach as a promising,yet unexplored tool for the precision and wireless control for the development of advanced soft actuators.

关键词： Light driven soft actuator all-optical manipulation laser manipulation

Mechanical Behaviour and Microstructure Evolution of Superplastic Mg-8.4 wt pct Li Alloy and Effect of Grain Size and Phase Ratio on Its Elongation

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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

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： EUROPIUM(III) TERBIUM(III) IONS

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

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