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Finite Element Analysis of 100 t Hot Metal Ladle in Process of Tipping

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Journal of Iron and Steel Research International 2010年第11期17卷 19-23页

作者： tian hong-yu CHEN Fu-rong XIE Rui-jun LI Shi-hui College of Materials Science and Engineering Inner Mongolia University of Technology Hohhot 010051 Inner Mongolia China Department of Mechanical and Electrical Engineering Baotou Light Industry Vocational and Technical College Baotou 014035 Inner Mongolia China

Hot metal ladle is an important part in continuous casting production line and its stress distribution has direct influence on its life. In the process of design and calibration of the large-sized hot metal ladle, it is of great significance to determine the stress distribution of each part of the ladle for safely and reliably running the device. Based on 100 t hot metal ladle which is designed by Baotou Iron and Steel Group, simulation of stress field was made by finite element software ANSYS 10.0 from different dumping angles. Through modeling, loading, restricting and calculating, strain and stress field distribution of the hot metal ladle were acquired. Finally, an assessment of strength and stiffness was made on the hot metal ladle. The results show that in the process of tipping for the hot metal ladle, maximum stress is 132 MPa and maximum strain is only 0. 064% ; maximum stress and strain have appeared in the stiffener plate which is located at the bottom of the trunnion, and strength and stiffness are qualified. The method, which is convenient and practical, reasonable and reliable, provides theoretical evidence for checking analysis and further optimal design of the hot metal ladle.

关键词： hot metal ladle stress field finite element analysis

Protection of Mice with a Divalent Tuberculosis DNA Vaccine Encoding Antigens Ag85B and MPT64

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 269-276页

作者： Xia tian, hong CAI, and yu-Xian ZHU* The National Laboratory of Protein Engineering and Plant Genetic Engineering, Peking University, Beijing 100871, China The National Laboratory of Protein Engineering and Plant Genetic Engineering Peking UniversityBeijing 100871 China

DNA vaccine may be a promising tool for controlling tuberculosis development. However, vaccines encoding single antigens of mycobacterium did not produce protective effect as BCG did. In the present study, we evaluated the immunogenicity and protective efficacy of a divalent DNA vaccine encoding two immunodominant antigens Ag85B and MPT64 of Mycobacterium tuberculosis. We found that both humoral and Th1-type (high IFN-γ, low IL-4) cellular responses obtained from the divalent DNA vaccine group were significantly higher than that conferred by BCG. RT-PCR results showed that antigens were expressed differentially in various organs in divalent DNA vaccine group. The survival rate for mice treated with the divalent DNA vaccine after challenging with high doses of virulent M. tuberculosis H37Rv was significantly higher than that of the BCG group or any of the single DNA vaccine group. Significant differ- ences were also found between the single and divalent DNA vaccinated mice in terms of body, spleen and lung weight. Bacterial loading decreased about 2000-fold in lungs and about 100-fold in spleens of divalent DNA vaccinated mice when compared with that of the control group. We conclude that our divalent DNA vaccine may be a better choice for controlling tuberculosis disease in animals.

关键词： tuberculosis divalent DNA vaccine immunogenicity protection

干扰我国人工草地生态系统的主要影响因素研究

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安徽农业科学 2011年第25期39卷 15600-15602页

作者：田育红北京师范大学地表过程与资源生态国家重点实验室北京100875

[目的]明确影响人工草地生态系统的关键因素。[方法]在参阅大量前人研究工作基础上,从播种方式、放牧强度、种植时限和施肥4个方面进行总结分析它们对人工草地生态系统的影响。[结果]混播方式比单播方式更有利于资源利用率和生态系统健... 详细信息

[目的]明确影响人工草地生态系统的关键因素。[方法]在参阅大量前人研究工作基础上,从播种方式、放牧强度、种植时限和施肥4个方面进行总结分析它们对人工草地生态系统的影响。[结果]混播方式比单播方式更有利于资源利用率和生态系统健康,而单播或隔行混播对增加土壤有机碳要比同行混播更为有利,同时隔行混播的草地产生的牧草产量要大于同行混播的草地,牧草产量最低的为单播草地;轻度和中度放牧有利于维持牧草的高产和高质以及草地的可持续发展,重度放牧则导致草地的退化;种植时限对植被群落结构和土壤理化性质的影响则具明显区域差异;长期施肥可有效提高土壤的有机碳含量以及牧草的产量和质量,但确定特定区域特定牧草的施肥量、施肥类型和比例是施肥效应发挥作用的关键。[结论]在进行人工草地种植时,要合理利用各因素的正面效应,有效控制人为干扰的深度和广度,避免或减弱负面作用的影响,为人工草地的高产、稳产打下良好的基础。

关键词：人工草地植被群落组成土壤理化性质主要影响因素

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转轨时期中国应对国际反倾销战略的实证分析

财经问题研究 2009年第6期 26-33页

作者：田玉红东北财经大学国际经济贸易学院辽宁大连116025

本文通过对1996—2007年国际对华反倾销以及中国相关经济数据的实证分析,将中国应对国际反倾销与经济转轨阶段的中国市场经济体制改革和对外开放等战略问题的关系进行澄清。结果表明,中国市场化程度越低,国际对华反倾销的次数不升反降,... 详细信息

本文通过对1996—2007年国际对华反倾销以及中国相关经济数据的实证分析,将中国应对国际反倾销与经济转轨阶段的中国市场经济体制改革和对外开放等战略问题的关系进行澄清。结果表明,中国市场化程度越低,国际对华反倾销的次数不升反降,中国的市场化改革不必以国际对华反倾销为转移;外商投资企业出口总额的逐年增长对于减少国际对华反倾销并无明显帮助,加工贸易和贸易竞争力对减少国际对华反倾销作用明显,中国的对外开放战略仍要坚持并在具体实施过程中不断改进;中国对外反倾销对国际对华反倾销形成一定的威慑作用,但是参与WTO争端解决机制的增加并没有减少国际对华反倾销的次数,其威慑作用远没有发挥出来。

关键词：国际反倾销转轨市场化对外开放

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中国高技术产业发展形势及对策分析

财经问题研究 2010年第6期 48-53页

作者：田玉红东北财经大学国际经济贸易学院辽宁大连116025

本文通过详细的数据分析,发现中国高技术产业不仅面临更大的国际国内压力,而且高技术产业的培育机制和形成机制都有待改善,因此,高技术产业发展有赖于充分切实地适用研发补贴,并建立以间接援助手段为主、以直接援助手段为辅的产业促进... 详细信息

本文通过详细的数据分析,发现中国高技术产业不仅面临更大的国际国内压力,而且高技术产业的培育机制和形成机制都有待改善,因此,高技术产业发展有赖于充分切实地适用研发补贴,并建立以间接援助手段为主、以直接援助手段为辅的产业促进机制。

关键词：高技术高技术产业形势

裁撤与留防:晚清勇营命运的双重变奏——对甲午战前勇营地位的一种解读

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山东社会科学 2005年第4期 104-107页

作者：田玉洪华东师范大学历史系上海200062

勇营在晚清已经成为国防力量的主体,但是在传统军事体制内却没有相应的位置,使勇营地位一直处于虚悬和朦胧状态。勇营身份的缺失,反映了清政府对勇营的依赖和排拒,表现了落后的国家政治生态的内在困境,以及勇营长期以来无法从既定系统... 详细信息

勇营在晚清已经成为国防力量的主体,但是在传统军事体制内却没有相应的位置,使勇营地位一直处于虚悬和朦胧状态。勇营身份的缺失,反映了清政府对勇营的依赖和排拒,表现了落后的国家政治生态的内在困境,以及勇营长期以来无法从既定系统中得到化解的危机。由此导致了清政府国家战略防御政策的混乱和矛盾,给晚清的国防建设带来了极为不利的影响。

关键词：勇营地位裁撤留防影响

铁磁/反铁磁双层膜中冷却场对交换偏置场的影响

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物理学报 2009年第4期58卷 2757-2761页

作者：田宏玉许小勇胡经国扬州大学物理科学与技术学院扬州225002

用铁磁畴壁模型研究了非补偿界面铁磁/反铁磁双层膜中冷却场(包括大小及其方向)对交换偏置场hE的影响.结果表明:当冷却场的方向与反铁磁层磁易轴一致时,hE大小与冷却场大小无关.当冷却场的方向偏离磁易轴时,hE的大小随偏离角度的增大有... 详细信息

用铁磁畴壁模型研究了非补偿界面铁磁/反铁磁双层膜中冷却场(包括大小及其方向)对交换偏置场hE的影响.结果表明:当冷却场的方向与反铁磁层磁易轴一致时,hE大小与冷却场大小无关.当冷却场的方向偏离磁易轴时,hE的大小随偏离角度的增大有缓慢的改变,但当冷却场的方向偏离到临界角度γc处,hE的大小发生突变,其γc的大小随冷却场的增大而增大.特别是当冷却场的偏离角度大于γc后,hE出现由负转正的现象,其转变点还与冷却场的大小有关.另外,hE与铁磁层原子层数NF的关系会发生由hE∝NF-1向hE∝NF-λ的转变,其中λ>1.其发生转变的条件与NF、冷却场大小和方向密切相关.

关键词：铁磁/反铁磁双层膜交换偏置冷却场

Temporal-Spatial Variances of Holocene Precipitation at the Marginal Area of the East Asian Monsoon Influences from Pollen Evidence

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Acta Botanica Sinica 2002年第7期44卷 864-871页

作者：刘鸿雁崔海亭田育红徐丽宏北京大学城市与环境学系北京100871

The woodland-steppe ecotone in the. southern Nei Mongol Plateau is located at the northern edge of the east Asian monsoon influences. A marked southeastern - northwestern (SE - NW) precipitation gradient exists in this region. Quantitative reconstruction of palaeo-precipitation of this region is helpful to reveal the development of monsoon climate and to predict die future desertification. Based on modern vegetation and surface pollen studies, a pollen-precipitation transfer function in the study region was established. Pollen data from three sediment sequences within the ecotone were used to reconstruct palaeo-precipitation during the Holocene. The processes of precipitation changes in the three sequences were quite different. There was a tendency of precipitation declined from the onset of the Holocene to 1 100 a BP in Haoluku. But, in Liuzhouwan and Xiaoniuchang, both located south of Haoluku, the annual precipitation reached highest values during 7 800 - 6 200 a BP and 7 200 - 5 000 a BP, respectively. The influences of southwestern (SW) monsoon and the variances of topographical conditions have possibly caused these temporal-spatial variances.

关键词： marginal area of the monsoon climate woodland steppe ecotone Nei Mongol Plateau pollen-climate transfer function

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数字化三相大功率逆变波形内模控制方法

电子学报 2011年第8期39卷 1883-1888页

作者：郜克存杨金辉戴瑜兴洪天宇湖南大学电气与信息工程学院湖南长沙410082 中国电子学会北京100036 斯伦贝谢中国公司北京100015

针对三相逆变电源数学模型在旋转αβ坐标系下的特点,提出了基于神经网络内模原理的逆变波形控制方案.用神经网络预估器作为逆变器的内部模型,用神经网络辨识预估逆变器正模型及其逆模型,在线修正、补偿内部模型与被控逆变器之间的模型... 详细信息

针对三相逆变电源数学模型在旋转αβ坐标系下的特点,提出了基于神经网络内模原理的逆变波形控制方案.用神经网络预估器作为逆变器的内部模型,用神经网络辨识预估逆变器正模型及其逆模型,在线修正、补偿内部模型与被控逆变器之间的模型失配.仿真和实验结果表明,该方案控制下系统稳压精度高,有较快的动态响应.

关键词：三相逆变电源逆变波形控制内模控制神经网络