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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1061-1072页

作者： wei hongming LI Mingchao LI Xiaoya ZHAN Wenyi LI Feiyang DAI Yanzhang ZOU Jianpeng State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Guangxi Fangchenggang Nuclear Power Co. Ltd.Fangchenggang 538000China

We review the fundamental properties and significant issues related to Cu/graphite *** particular,recent research on the interfacial modification of Cu/graphite composites is addressed,including the metal-modified layer,carbide-modified layer,and combined modified ***,we propose the use of ternary layered carbide as an interface modification layer for Cu/graphite composites.

关键词： Cu/graphite composites interfacial bonding surface modification wettability layered ternary carbides

Effect of Sintering Temperature and Hydrophobic Treatment on the Microstructure and Properties of Copper-Graphite Composites

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Journal of Wuhan University of Technology(Materials Science) 2022年第3期37卷 305-313页

作者： ZOU Jianpeng wei hongming XIAO Cong State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China State Key Laboratory for System Integration of High Power AC Drive Electric Locomotive Zhuzhou 412001China

Copper-graphite composites were prepared by spark plasma sintering(SPS)using coppercoated graphite *** surfaces were successfully constructed by chemical etching and surface *** density,metallographic structure,microstructure,Shore hardness,resistivity,water contact angle,and friction/wear properties of the composites were investigated using the Archimedes drainage method,a metallographic microscope,a scanning electron microscope,a hardness tester,a resistometer,a surface science tester,and a friction *** results showed that the relative density and Shore hardness of the copper-graphite composites increased slightly from 90.04%and 56 HSD to 92.66%and 59 HSD,respectively,when the sintering temperature increased from 700 to 900℃.The copper and graphite phases in the copper-graphite composites were uniformly distributed with a continuous and network-like structure at various sintering *** interface between the copper and graphite was in good condition,without any obvious cracks or *** optimum process for hydrophobic surface construction included etching with a 1 mol/L K_(2)Cr_(2)O_(7)-H_(2)SO_(4)solution for 1 min,and soaking in a 0.09 mol/L cetylbenzene sulfonic acid alcohol solution for 1 *** contact angle of the copper-graphite composite reached 130°.Hydrophobic treatment was beneficial for reducing the friction coefficient(from 0.18-0.19 to 0.13-0.15)and the wear rate(from 4.1-6.2×10^(-3)to 1.1-2.1×10^(-3)mm^(3)/(N·m)),demonstrating obvious antifriction and wear-resisting *** resistivities of the hydrophobic-treated samples increased slightly,from(4-8)×10^(-7)Ω·m to(5-15)×10^(-7)Ω·m,meeting the resistivity requirements of copper-graphite composite pantograph sliders and current receiver sliders in actual working conditions.

关键词： spark plasma sintering(SPS) copper-graphite composite chemical etching shore hardness friction and wear properties resistivity

Optimization of Quenching Process for ZTAP/ High Chromium Cast Iron Composites

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Journal of Wuhan University of Technology(Materials Science) 2022年第6期37卷 1137-1142页

作者： wei hongming JIANG Yehua ZHANG Xiaozu JIA Yuanwei ZHOU Mojin XUE Da Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

In order to solve the problem of cracking of ZTAP(Zirconia toughened alumina ceramic particles)reinforced HCCI(high chromium cast iron)matrix composites,the quenching process was *** reinforced HCCI matrix composites were prepared by infiltration method with gravity sand *** thermal expansion curves of HCCI and the composites were measured at different cooling rates by *** microstructure of the HCCI matrix and the composites were characterized by X-ray diffraction,light microscopy,SEM,ESD,and *** tested mechanical properties include Rockwell hardness and impact *** deformation differences of HCCI and the composite at different cooling rates were obtained according to the test results of thermal expansion coefficient curve and changes in microstructure and mechanical properties,and air cooling was the most favorable for the composites to have good hardness and not easy to *** cooling rate during air cooling is approximately equal to 21℃/s in this *** the quenching process was air cooling,the impact toughness and hardness of the composites are 3.7 J/cm^(2) and 61.8 HRC,respectively,and the deformation difference between the composites and HCCI was 20μm at 300℃.

关键词： composites ZTAP quenching cooling rate microstructure thermal expansion

乌兰夫民族工作思想的主要内容——纪念乌兰夫诞辰100周年

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黑龙江民族丛刊 2006年第6期 14-22页

作者：金炳镐魏鸿鸣中央民族大学中国民族理论与民族政策研究院中华工商出版社北京100081 北京100080

乌兰夫是党和国家优秀的领导人,卓越的民族工作领导人。他在我党我国民族工作的长期实践中形成了民族工作思想,其内容十分丰富。本文仅就乌兰夫关于民族平等、民族团结、民族区域自治、发展少数民族经济方面的思想加以研究和论述。

关键词：乌兰夫民族工作思想主要内容

Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao Zejia He Jia Zheng hongming Bai Jia-Sheng Rao Guiyun Song wei Song Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task

适用于移动机械手无关节状态反馈情况的基于人-机-机协作的无标定视觉伺服控制

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机器人 2017年第2期39卷 197-204页

作者：纪鹏宋爱国吴常铖魏宏明宋子墨张琪东南大学仪器科学与工程学院江苏南京210096

移动机器人在执行某些危险品处置任务时,其搭载的机械臂的关节状态可能会因为测量器件的损坏而无法获知.为了不在召回机器人上延误危险品的处置时间,提出一种适用于移动机械手无关节状态反馈情况的基于人-机-机协作(HRRC)的无标定视觉... 详细信息

移动机器人在执行某些危险品处置任务时,其搭载的机械臂的关节状态可能会因为测量器件的损坏而无法获知.为了不在召回机器人上延误危险品的处置时间,提出一种适用于移动机械手无关节状态反馈情况的基于人-机-机协作(HRRC)的无标定视觉伺服控制系统.首先建立能反映机械手关节状态的虚拟外骨骼(虚拟模型),方法是在另一台机器人在线拍摄到的监控图像上,使用人机交互(HCI)输入设备(如鼠标)手动框选关节所在的区域.虚拟外骨骼与多关节跟踪算法配合可以实现对机械臂对应关节的导向控制及末端姿态保持.为了利用人工导引点对虚拟外骨骼进行导引控制,通过广义回归神经网络(GRNN)来映射虚拟外骨骼的末端与关节角的关系.最后,在轴孔装配实验中,本文方法能够使机械手末端在人工导引下完成任务,且能使末端姿态误差保持在±1?左右;而常规的单关节控制方式无法控制机械手末端完成任务,且无法实现末端姿态保持.对比实验结果验证了本文提出的控制系统在无关节状态反馈的情况下能够帮助操作人员直观地使用机械手处置目标,并且在此过程中能够使机械手末端保持在指定姿态.

关键词：无标定摄像头视觉伺服移动机器人机械手神经网络

送粉式激光增材和铣削减材复合制造316L不锈钢的表面质量及力学性能

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激光与光电子学进展 2022年第1期59卷 260-266页

作者：陈峰宋长辉杨永强魏宏鸣周恒华南理工大学机械与汽车工程学院广东广州510641

为了研究送粉式激光增材和铣削减材复合制造零件的表面质量及力学性能,以316L不锈钢粉末为原料,通过"增材-减材-增材-减材"交替循环的方式进行样件的制造,并对其表面粗糙度、显微硬度和力学性能进行分析测试。结果表明:送粉式激光增材... 详细信息

为了研究送粉式激光增材和铣削减材复合制造零件的表面质量及力学性能,以316L不锈钢粉末为原料,通过"增材-减材-增材-减材"交替循环的方式进行样件的制造,并对其表面粗糙度、显微硬度和力学性能进行分析测试。结果表明:送粉式激光增材和铣削减材复合制造样件的表面粗糙度随着铣削速度的增大而下降,随着每齿进给量的增加而增大;送粉式激光增材和铣削减材复合制造样件的表面粗糙度较传统工艺生产的基板试样更低,显微硬度较增材制造样件和锻造件更高,抗拉强度和屈服强度比增材制造样件分别提高了5%和60.5%,但断后伸长率却有所降低。送粉式激光增材和铣削减材复合制造技术能够制造出具有高表面质量和优良力学性能的零件,可直接应用于316L不锈钢轮胎模具等零件的制造。该技术充分融合了增材制造的高材料利用率、高自由度以及减材制造的高精度、高表面质量优势,可以获得结构复杂、形状精度和表面质量高的零件。

关键词：激光技术激光定向能量沉积铣削加工复合制造 316L不锈钢表面质量力学性能

Extracellular vesicles from human urine-derived stem cells delay aging through the transfer of PLAU and TIMP1

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1166-1186页

作者： Shanshan Rao Zehui He Zun Wang Hao Yin Xiongke Hu Yijuan Tan Tengfei Wan Hao Zhu Yi Luo Xin Wang hongming Li Zhenxing Wang Xinyue Hu Chungu Hong Yiyi Wang Mingjie Luo wei Du Yuxuan Qian Siyuan Tang Hui Xie Chunyuan Chen Department of Orthopedics Movement System Injury and Repair Research CenterXiangya HospitalCentral South UniversityChangsha 410008China Hunan Key Laboratory of Angmedicine Changsha 410008China Xiangya School of Nursing Central South UniversityChangsha 410013China Department of Pediatric Orthopedics Hunan Children’s HospitalUniversity of South ChinaChangsha 410007China Department of Respiratory Medicine Xiangya HospitalCentral South UniversityChangsha 410008China School of Nursing Xinjiang Medical UniversityUrumqiXinjiang 830000China Department of Rehabilitation Xiangya HospitalCentral South UniversityChangsha 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha 410008China

Aging increases the risks of various diseases and the vulnerability to *** senescence is a hallmark of aging that contributes greatly to aging and aging-related *** study demonstrates that extracellular vesicles from human urine-derived stem cells(USC-EVs)efficiently inhibit cellular senescence in vitro and in *** intravenous injection of USC-EVs improves cognitive function,increases physical fitness and bone quality,and alleviates aging-related structural changes in different organs of senescence-accelerated mice and natural aging *** anti-aging effects of USC-EVs are not obviously affected by the USC donors’ages,genders,or health *** analysis reveals that USC-EVs are enriched with plasminogen activator urokinase(PLAU)and tissue inhibitor of metalloproteinases 1(TIMP1).These two proteins contribute importantly to the anti-senescent effects of USC-EVs associated with the inhibition of matrix metalloproteinases,cyclin-dependent kinase inhibitor 2A(P16INK4a),and cyclin-dependent kinase inhibitor 1A(P21cip1).These findings suggest a great potential of autologous USC-EVs as a promising anti-aging agent by transferring PLAU and TIMP1 proteins.

关键词： Extracellular vesicles Urine-derived stem cells Cellular senescence Anti-aging PLAU TIMP1 Senescence-accelerated mice Natural aging mice

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logR-logT图与太阳系未知行星

科技通报 2011年第1期27卷 9-13页

作者：潘彩娟王小波韦鸿铭百色学院物理与电信工程系广西百色533000

利用logR-logT图研究太阳系的行星卫星系统,得出八大行星卫星系统都符合开普勒第三定律,推导出行星卫星系统logR-logT图线截距与中心天体质量的关系;通过描绘未知行星卫星系统、水星卫星系统和金星卫星系统的logR-logT图线,推测未知行... 详细信息

利用logR-logT图研究太阳系的行星卫星系统,得出八大行星卫星系统都符合开普勒第三定律,推导出行星卫星系统logR-logT图线截距与中心天体质量的关系;通过描绘未知行星卫星系统、水星卫星系统和金星卫星系统的logR-logT图线,推测未知行星的质量和公转周期,以及水星和金星的未知卫星可能存在的位置与周期。

关键词：太阳系 logR-logT图未知行星未知卫星

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核电汽轮机高压缸表面换热系数修正计算

热力发电 2018年第9期47卷 109-114页

作者：魏红明谢诞梅曹超李浩中国大唐集团科学技术研究院有限公司西北分公司陕西西安710065 武汉大学动力与机械学院湖北武汉430072

准确的换热系数计算公式是数值分析汽轮机高压缸温度分布、应力及汽密性的基础。目前国内外关于核电汽轮机高压缸换热系数的研究较少,汽缸表面换热系数一直没有统一的公式。本文选用并修正了高压缸内表面换热系数计算公式,对比高压缸壁... 详细信息

准确的换热系数计算公式是数值分析汽轮机高压缸温度分布、应力及汽密性的基础。目前国内外关于核电汽轮机高压缸换热系数的研究较少,汽缸表面换热系数一直没有统一的公式。本文选用并修正了高压缸内表面换热系数计算公式,对比高压缸壁面温度的计算值和实际监测数据,得到了适用于核电汽轮高压缸的换热系数模型,求解了汽缸温度分布,并对高压缸的应力及中分面汽密性进行了分析。结果表明:该模型具有较高的计算精度,最大误差为4.3%;停机过程中高压缸各表面换热以强迫对流为主,高压缸进汽及排汽处缸表面的换热系数量级在1 000~2 000 W/(m^2·K);停机过程中高压缸内外壁最大温差为29.9℃。

关键词：核电汽轮机高压缸汽密性换热系数计算公式温度场数值模拟