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Wear Evaluation on Ni_3Al/MnS Composite Related to Metallurgical Processes

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Journal of Iron and Steel Research International 2012年第7期19卷 46-54页

作者： Karin Gong LUO He-li ZHOU Zhi-feng TIAN Zhi-ling Lars Nyborg li chang-hai Department of Materials and Manufacturing Technology Chalmers University of Technology Gothenburg Se-412 96 Sweden China Iron and Steel Research Institute Group Beijing 100081 China Department of Manufacturing Engineering and Engineering Management City University of Hong Kong Hong Kong China

Iron alloyed Ni3Al with composition of Ni-18. 8Ab10. 7Fe-0. 5Mn-0. 5Ti-0. 2B in atom percent （NAC alloy） showed attractive tribological properties under unlubrication condition at room temperature. The alloy was prepared by hot isostatic pressing （HIP） process. The wear properties were associated with its intrinsic deformation mechanism. Unfortunately, the single phase NAC-alloy worked inadequately with its counterpart disk, and also showed a poor machinability. In the present work, NAC-alloy matrix composite with 6 % （volume percent） MnS particle addi- tion was studied to improve its wear behaviors and performance on machining. Two metallurgical processes of HIP and vacuum casting were applied to produce the testing materials. Pin-on-disk （POD） measurements were carried out at room temperature. A commercial vermicular graphite cast iron was selected as a reference material. The counter- part disk was made of a grey cast iron as liner material in ship engines. The contact pressures of 2.83 MPa and 5.66 MPa were normally applied in the tests. The investigation indicated that MnS particle addition in the NAC-alloy composites functions as an effective solid lubricant, and improved wear properties and machinability of the materials. Obvi- ously, as-cast NAC-alloy with in-situ formed MnS-phase was working more effectively with the counterpart, compa- ring to the HIPed NAC-alloy composite with MnS particles. At the high contact pressure of 5.66 MPa, the specific wear rate of the as-cast NAC-alloy composite was high. The phenomenon of the negative effect is mostly due to the brittle second NiAl phase as evidenced in the microstructure analysis.

关键词： HIP processing friction coefficient specific wear rate intermetallics sliding wear casting machinability

Numerical Simulation of Temperature Field and Thermal Stress Field of Work Roll During Hot Strip Rolling

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Journal of Iron and Steel Research International 2007年第5期14卷 18-21页

作者： li chang-sheng YU hai-liang DENG Guan-yu liU Xiang-hua WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Based on the thermal conduction equations, the three-dimensional （3D） temperature field of a work roll was investigated using finite element method （FEM）. The variations in the surface temperature of the work roll during hot strip rolling were described, and the thermal stress field of the work roll was also analyzed. The results showed that the highest roll surface temperature is 593 ℃, and the difference between the minimum and maximum values of thermal stress of the work roll surface is 145.7 MPa. Furthermore, the results of this analysis indicate that temperature and thermal stress are useful parameters for the investigation of roll thermal fatigue and also for improving the quality of strip during rolling.

关键词： hot strip mill roll temperature field thermal stress finite element method

Metabolomic Profiling of Mice Exposed toα-amanitin Using Ultra-performance liquid Chromatography Quadrupole Time-of-flight Tandem Mass Spectrometry

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Biomedical and Environmental Sciences 2023年第3期36卷 289-294页

作者： li Lei ZHENG Chong YE Jian Fang ZHU Kai ZHOU Yi Bing liU Jia GAO Ming WU Yu Tian liU Yong Ting liU li Ya liN Ye li hai chang ZHANG Quan GUO Hua Clinical Laboratory Guizhou Provincial Center for Disease Control and PreventionGuiyang 550004GuizhouChina Clinical Laboratory Guiyang Provincial Center for Disease Control and PreventionGuiyang 550002GuizhouChina

Numerous instances of poisoning caused by the ingestion of mushrooms are reported annually worldwide,with most mushroom poisoning deaths caused by the ingestion of toxic amanita *** is the main toxic component of aman... 详细信息

关键词： Metab ani annually

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火电厂凝结水精处理系统调试

中国电力 2010年第6期43卷 69-73页

作者：李长海西北电力建设调试施工研究所陕西西安710032

大容量、高参数火力发电厂设置凝结水精处理系统,不论从防止受热面和汽轮机腐蚀结垢,还是保证机组安全运行都是必要的。新建机组凝结水精处理系统的调试为其投运前必不可少的环节。文中介绍了亚临界机组凝结水精处理系统的调试过程:罐... 详细信息

大容量、高参数火力发电厂设置凝结水精处理系统,不论从防止受热面和汽轮机腐蚀结垢,还是保证机组安全运行都是必要的。新建机组凝结水精处理系统的调试为其投运前必不可少的环节。文中介绍了亚临界机组凝结水精处理系统的调试过程:罐体的内部检查、系统水压试验、程序连锁保护、程控调试及调试过程中的注意事项;详细讨论了树脂分离传送过程中流量配比控制的重要性,针对调试中遇到的问题提出了解决方法。运行结果表明,经调试后设备达到设计要求,出水水质合格,可满足机组运行工况要求。

关键词：火电厂凝结水精处理高速混床调试

基于GM(1,2)模型的多步自调节灰色预测控制算法

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西安石油大学学报（自然科学版） 2009年第3期24卷 92-95页

作者：郭颖李昌海辽宁石油化工大学信息工程学院辽宁抚顺113001

基于GM(1,2)灰色模型和一种新型综合偏差,提出了基于GM(1,2)模型的多步自调节灰色预测控制算法.该算法可对系统输出偏差和预测偏差进行合成形成一个在线多步综合偏差,用此偏差代替传统最优控制算法中的偏差项,这样算法既有在线预测系统... 详细信息

基于GM(1,2)灰色模型和一种新型综合偏差,提出了基于GM(1,2)模型的多步自调节灰色预测控制算法.该算法可对系统输出偏差和预测偏差进行合成形成一个在线多步综合偏差,用此偏差代替传统最优控制算法中的偏差项,这样算法既有在线预测系统未来多步行为的功能,又能根据预测模型精度实时调节预测值在控制回路中的作用,减小了预测误差对系统的不利影响.仿真结果表明,该算法可获得较好的控制跟踪效果.

关键词：灰色预测控制综合偏差 GM(1,2)模型

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基于热传导模型的血流灌注率无损量测研究

工程热物理学报 2018年第8期39卷 1842-1848页

作者：李长玉戴海燕张继锋李细霞华南理工大学广州学院广州510800

建立了多层皮肤组织的热传导模型,利用有限元方法对模型进行了求解分析,发现当在皮肤组织表面进行常热流量加热时皮肤组织表面最终恒定温度和血流灌注率的大小有关,利用ExpAssoc函数进行拟合得到了二者之间的关系曲线,并且根据此关系曲... 详细信息

建立了多层皮肤组织的热传导模型,利用有限元方法对模型进行了求解分析,发现当在皮肤组织表面进行常热流量加热时皮肤组织表面最终恒定温度和血流灌注率的大小有关,利用ExpAssoc函数进行拟合得到了二者之间的关系曲线,并且根据此关系曲线设计了血流灌注率无损量测装置,对人体皮肤组织的血流灌注率进行了量测,发现测量结果与计算结果趋势一致,并且和其他文献报道的结果吻合度较高。此方法简单有效,也可应用于其它生物组织血流灌注率的无损量测.

关键词：血流灌注率无损量测温度场热传导

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上海特奥会媒体报道特点

上海体育学院学报 2008年第3期32卷 30-33页

作者：郭讲用李长海上海体育学院体育人文学院上海200438 解放军军事体育进修学院军队基层体育教研室广东广州510502

采用抽样调查法,分析上海特奥会媒体报道的特点。发现:集中报道特奥会的主要是以政府利益为导向的国家媒体,而以经济利益为导向的商业媒体对此鲜有关注。国家媒体对特奥会的报道特点为淡化竞技、突出人文、彰显文化。具体报道内容涉及... 详细信息

采用抽样调查法,分析上海特奥会媒体报道的特点。发现:集中报道特奥会的主要是以政府利益为导向的国家媒体,而以经济利益为导向的商业媒体对此鲜有关注。国家媒体对特奥会的报道特点为淡化竞技、突出人文、彰显文化。具体报道内容涉及国家形象与上海城市形象的宣传展示,特奥文化的传播,"平等、接纳、包容"的特奥理念解读,人文奥运精神的报道,特奥的教育价值阐释,对体育快乐本源的揭示等方面。

关键词：上海特奥会国家媒体商业媒体

The crack tip fields of Mode Ⅱ stationary growth crack on bimaterial interface

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Journal of Marine Science and Application 2003年第2期2卷 11-16页

作者： TANG li-qiang,liU chang-hai, and ZHENG Gui School of Civil Engineering, Harbin Engineering University, Harbin 150001 , China Harbin Engineering University School of Civil Engineering Harbin China (GRID:grid.33764.35) (ISNI:***)

A mechanical model is established for mode II interfacial crack static growing along an elastic-elastic power law creeping bimaterial interface. For frictional contact of boundary conditions on crack faces, asymptotic solutions of the stresses and strains of near tip-crack are got. It was shown that in stable creep growing phase, elastic deformation and viscous deformation are equally dominant in the near-tip field, the stress and strain have the same singularity and there is not the oscillatory singularity the field. Through numerical calculation , it is shown that the frictional coefficient η notably influence the crack-tip field.

关键词： an elastic-elastic power law creeping material near-tip field of mode Ⅱ interfacial crack the frictional effect

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大连国际会议中心消防设计探讨

消防科学与技术 2012年第9期31卷 946-948页

作者：许佳华黎昌海大连市消防支队辽宁大连116033 中国科学技术大学火灾科学国家重点实验室安徽合肥230026

针对大连国际会议中心建筑特点分别对共享大厅、舞台进行火灾危险性分析,运用性能化消防设计的方法从防火分隔、烟气控制、人员疏散、探测报警与灭火系统、智能疏散指示和事故照明、钢结构保护、火灾荷载控制等方面提出消防设计对策,并... 详细信息

针对大连国际会议中心建筑特点分别对共享大厅、舞台进行火灾危险性分析,运用性能化消防设计的方法从防火分隔、烟气控制、人员疏散、探测报警与灭火系统、智能疏散指示和事故照明、钢结构保护、火灾荷载控制等方面提出消防设计对策,并分别验证消防设计的可行性。

关键词：国际会议中心火灾危险性性能化消防设计