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铝合金TIG焊自适应控制方法

上海交通大学学报 2010年第S1期44卷 160-162,166页

作者：王建军陈善本上海第二工业大学电子与电气工程学院上海201209 上海交通大学材料科学与工程学院上海200240

通过分析铝合金焊接过程的特点,将随机系统理论引入焊接过程,建立了焊接参数与熔池几何参数之间的随机系统模型.针对铝合金TIG焊特点,设计了基于电流最小方差调节的焊缝熔宽自适应控制器,通过实时调控焊接电流,使其适应焊接过程散热条... 详细信息

通过分析铝合金焊接过程的特点,将随机系统理论引入焊接过程,建立了焊接参数与熔池几何参数之间的随机系统模型.针对铝合金TIG焊特点,设计了基于电流最小方差调节的焊缝熔宽自适应控制器,通过实时调控焊接电流,使其适应焊接过程散热条件的随机变化.焊接试验结果表明,电流自适应控制方法可以实现对铝合金TIG焊缝成型的良好控制.

关键词：铝合金 TIG焊随机模型自适应控制

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燃料电池机器人动力系统多模型切换控制

上海交通大学学报 2010年第S1期44卷 122-125页

作者：吕学勤邱荣福吴毅雄上海电力学院信息与控制工程系上海200090 上海交通大学材料科学与工程学院上海200240

针对燃料电池驱动的自主机器人动力系统中,燃料电池、辅助动力单元、电动机传动系统、机器人本体等子模型多造成的控制复杂性,介绍了基于燃料电池驱动的机器人系统的系统构成.阐述了燃料电池机器人的DC/DC变结构控制和基于聚类的模糊滑... 详细信息

针对燃料电池驱动的自主机器人动力系统中,燃料电池、辅助动力单元、电动机传动系统、机器人本体等子模型多造成的控制复杂性,介绍了基于燃料电池驱动的机器人系统的系统构成.阐述了燃料电池机器人的DC/DC变结构控制和基于聚类的模糊滑模变结构多模型切换控制,并简述了基于LABview的燃料电池机器人系统虚拟仿真平台的建立.

关键词：燃料电池机器人滑模变结构控制多模型切换

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基于实验铝合金激光小孔焊熔池表面速度计算

上海交通大学学报 2008年第S1期42卷 152-154页

作者：高志国黄坚李铸国吴毅雄上海市激光制造及材料改性重点试验室(筹) 上海200240 上海交通大学材料科学与工程学院上海200240

为了解决激光焊接铝合金熔池表面液态金属流动速度量值化问题,结合高速摄影装置与波动理论,提出了计算激光焊焊接过程中铝合金熔池表面液体流速的计算方法.根据有限深度液体流动模型,波速取决于液体波传播的波长以及液体深度这两个物理... 详细信息

为了解决激光焊接铝合金熔池表面液态金属流动速度量值化问题,结合高速摄影装置与波动理论,提出了计算激光焊焊接过程中铝合金熔池表面液体流速的计算方法.根据有限深度液体流动模型,波速取决于液体波传播的波长以及液体深度这两个物理量,采用高速摄影对焊接过程中熔池的流动形态进行拍摄,得到进行波的波长;对焊缝截面的熔深进行测量得到液体的深度,可以计算熔池表面液体的流动速度.研究表明,在激光束功率为6 kW,焊接速度分别为0.066 7,0.075,0.083 5 m/s的高速焊情况下,熔池表面的流动速度可达0.065 8,0.064,0.072 m/s.

关键词：高速摄影激光焊铝合金表面速度

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水冷壁高温腐蚀机制及机器人检测技术

上海交通大学学报 2008年第S1期42卷 93-96页

作者：吕学勤刘刚郑小霞吴毅雄上海电力学院信控系上海200090 上海交通大学材料科学与工程学院上海200240

阐述了锅炉水冷壁发生高温腐蚀的机制与条件,介绍了用于火力发电站的锅炉水冷壁检测机器人的发展情况,以及各种爬壁机器人的本体结构、磁路设计及控制系统等。由此得出水冷壁检测机器人能够缩短作业周期、提高电站的经济效益、降低劳动... 详细信息

阐述了锅炉水冷壁发生高温腐蚀的机制与条件,介绍了用于火力发电站的锅炉水冷壁检测机器人的发展情况,以及各种爬壁机器人的本体结构、磁路设计及控制系统等。由此得出水冷壁检测机器人能够缩短作业周期、提高电站的经济效益、降低劳动强度并提高检测精度.

关键词：水冷壁高温腐蚀爬壁机器人

Sorption of a triazol derivative by soils: importance of surface acidity

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Journal of Environmental sciences 2003年第3期15卷 383-387页

作者： WU De-yi (school of Environmental science and engineering, shanghai jiaotong university, shanghai 200240, china.) school of Environmental science and engineering Shanghai Jiaotong University 上海 200240

The sorption of a triazol derivative, 1-(4-chlorophenyl)- 4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)penten-3-ol with a common name of S3307D, on fifteen soils and three H_2O_2-treated soils was investigated. The sorption isotherm for each untreated and treated soil was non-linear, and was best fitted to Freundlich sorption equation. Soils containing high amount of clay content or organic matter or both sorbed much higher amounts of the chemical than soils that had low contents of these soil constituents. H_2O_2-treated soils showed considerable sorptive affinity for S3307D. It was concluded that both organic matter and mineral fraction in natural soils contributed to the sorption of the basic compound. Sorption by the H_2O_2 treated soils increased as suspension pH decreased, but all suspension pHs exceeded the pKa of the compound by more than two units. This implies that organic base protonation can occur on surfaces of soil components, and surface acidity (exchangeable acidity ) is important in sorption process of the organic base rather than suspension pH.

关键词： sorption organic base soil surface acidity

NUMERICAL SIMULATION OF MORPHOLOGY OF POLYMER CHAIN COILS IN COMPLEX FLOWS

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Chinese Journal of Polymer science 2005年第5期23卷 453-462页

作者： Hong Zheng Wei Yu Chi-xing Zhou Department of Polymer materials science & engineering,shanghai jiaotong university,shanghai 200240,china Department of Polymer materials science & engineering Shanghai Jiaotong University Shanghai 200240 China

A new coupled finite element formulation is proposed to calculate a conformation tensor model in two complex flows： a planar contraction flow and a planar flow around a symmetrically placed cylinder. The components of conformation tensor are first computed together with the velocity and pressure to describe the change of morphology of polymer chain coils in flow fields. Macroscopic quantities of viscoelastic flow are then calculated based on the conformation tensor. Comparisons between the numerical simulations and experiments for stress patterns and velocity profiles are carried out to prove the validity of the method.

关键词： Viscoelastic flow Morphology Complex flows Conformation tensor model Finite element method (FEM).

A Resistivity Gradient Piezoelectric FGM Actuator

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Journal of materials science & Technology 2000年第4期16卷 383-386页

作者： S. U.Adikary and Zhongyan MENG (school of materials science and engineering, shanghai university, shanghai 201800, china) Dengren JIN (school of materials science and engineering, shanghai jiaotong university, shanghai 200030, china) school of materials science and engineering Shanghai University Shanghai 201800 China school of materials science and engineering Shanghai Jiaotong University Shanghai 200030 China

A resistivity gradient actuator based on lead zirconate titanate ceramics was successfully developed and the bending deflections up to 140 μm were obtained. The actuator material was a matrix of PZT ceramic into which smooth gradient of piezoelectric activity was introduced. The application of an electric field then causes the actuator to bend due to differential strains induced by the piezoelectric effect. The resistivity gradient of the actuator was achieved by doping PZT with suitable donor and acceptor dopants. PZT powder was modified and synthesized by using two stage powder fabrication method. The actuator was fabricated by uniaxial pressing followedby isostatic pressing with two layers of different resistivities.

关键词： PZT FGM

Kinetic theory of self-condensing vinyl polymerization

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science china Chemistry 2010年第12期53卷 2429-2439页

作者： ZHOU ZhiPing 1 & YAN DeYue 2 1 school of materials science and engineering,Jiangsu university,Zhenjiang 212013,china 2.school of Chemistry and Chemical engineering,shanghai Jiao Tong university,shanghai 200240,china school of materials science and engineering Jiangsu University Zhenjiang China school of Chemistry and Chemical engineering Shanghai Jiao Tong University Shanghai China

This review introduces the kinetic theory of self-condensing vinyl polymerization (SCVP),including the SCVP of AB inimers,the SCVP with non-equal reactivity between A and B groups,the SCVP in the presence of a small amount of multifunctional initiators,also the SCVP of both inimers and *** analytical expressions of various molecular parameters for the resulting hyperbranched polymers,such as the molecular size distribution function,the average molecular weight,the polydispersity index and the degree of branching,are reviewed systematically.

关键词： kinetic theory self-condensing vinyl polymerization (SCVP) hyperbranched polymers

Influence of Mo on the microstructure and mechanical properties of TiC-based cermets

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Rare Metals 2010年第4期29卷 346-350页

作者： WANG Xingqing,HE Xiaoxiang,and GUO Hailiang school of materials science and engineering,shanghai university,shanghai 200072,china school of materials science and engineering Shanghai University Shanghai China

The microstructures and mechanics properties of TiC-based cermets composed of TiC, WC, Ni, Co, Mo, and Cr3C2 were investigated. The results show that Mo has a great effect on the sintering densification, microstructures, and mechanical properties. The microstructures and distribution of Mo and Ti in the TiC-based cermets were analyzed. It was indicated that a new phase with Ti, Mo, W, and C was formed on the rim of （Ti,W）C grains by means of an addition of Mo into the TiC-based cermets. The new phase with a surrounding structure was of great aid to improve the wettability of the liquid phase on the solid phase surface of TiC, decrease the porosity and refine the grains of the hard phase, which gave rise to the increase in strength and hardness. The properties of the TiC-based cermets could be further improved to some extent by adding WC, Cr2C3, and Co.

关键词： TiC-based cermets Mo effect sintering densification microstructure mechanical properties