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The fundamental plane relation of early-type galaxies:environmental dependence

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Research in Astronomy and Astrophysics 2015年第5期15卷 651-662页

作者： lei Hou yu wang Department of Astronomy University of Science and Technology of China

Using a sample of 70 793 early-type galaxies from SDSS DR7, we study the environmental dependence of the fundamental plane relation. With the help of the galaxy group catalog based on SDSS DR7, we calculate the fundamental planes in different dark matter halo mass bins for both central and satellite galaxies. We find the environmental dependence of the fundamental plane coefficients is similar in the g, r, i and z bands. The environmental dependence for central and satellite galaxies is significantly different. Although the fundamental plane coefficients for centrals vary systematically with the halo mass, those of satellites are similar in different halo mass bins. The discrepancy between centrals and satellites is significant in small halos, but negligible in the largest halo mass bins. These results remain the same when we only keep red galaxies, or galaxies with b/a 〉 0.6, or galaxies in a specific radius range in the sample. After the correction for the sky background, the results are still similar. We suggest that the different environmental effects of the halo mass on centrals and satellites may arise from their different quenching processes.

关键词： galaxies elliptical and lenticular -- galaxies halo -- galaxies statistics

Secondary Electron Emission from Carbon Foils Induced by Mutli-charged Heavy Ions near Bohr Velocity

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IMP & HIRFL Annual Report 2011年第1期 48-48页

作者： yu Yang Zhao Yongtao wang yuyu Cheng Rui Zhou Xianming lei yu wang Xing Li Yongfeng Ren Jieru Sun yuanbo Xu Ge

Dynamic Bending of Bionic Flexible Body Driven by Pneumatic Artificial Muscles(PAMs) for Spinning Gait of Quadruped Robot

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 11-20页

作者： lei Jingtao yu Huangying wang Tianmiao School of Mechatronic Engineering and Automation Shanghai University School of Mechanical Engineering and Automation Beihang University

The body of quadruped robot is generally developed with the rigid structure. The mobility of quadruped robot depcnds on the mechanical properties of the body mechanism, It is difficult for quadruped robot with rigid structure to achieve better mobility walking or running in the unstructured environment. A kind of bionic flexible body mechanism for quadruped robot is proposed, which is composed of one bionic spine and four pneumatic artificial muscles（PAMs）. This kind of body imitates the four-legged creatures＇ kinematical structure and physical properties, which has the characteristic of changeable stiff＇hess, lightweight, flexible and better bionics. The kinematics of body bending is derived, and the coordinated movement between the flexible body and legs is analyzed. The relationship between the body bending angle and the PAM length is obtained. The dynamics of the body bending is derived by the floating coordinate method and Lagrangian method, and the driving tbrce of PAM is determined. The experiment of body bending is conductcd, and the dynamic bending characteristic of bionic flexible body is evaluated. Experimental results show that the bending angle of the bionic flexible body can reach 18. An innovation body mechanism for quadruped robot is proposed, which has the characteristic of flexibility and achieve bending by changing gas pressure of PAMs. The coordinated movement of the body and legs can achieve spinning gait in order to improve the mobility of quadruped robot.

关键词： quadruped robot bionic flexible body PAM spinning gait dynamics

Experimental investigation on uniaxial cyclic plasticity of cast AZ91 magnesium alloy

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Journal of Magnesium and Alloys 2023年第9期11卷 3255-3271页

作者： yu lei Ziyi wang Guozheng Kang Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China

The uniaxial cyclic plasticity of cast AZ91 magnesium(Mg) alloy was investigated by conducting a series of cyclic straining and stressing tests at room temperature, and a unique cyclic plasticity(especially for ratchetting) and its physical nature were revealed. The experimental results demonstrate that the cast AZ91 Mg alloy behaviors tension-compression symmetry, because the dislocation slipping and twinning occur during both the tensile and compressive deformations;although the cast AZ91 alloy presents a certain pseudo-elastic behavior during unloading due to the detwinning, there is no obvious S-shaped asymmetric hysteresis loop like that of wrought Mg alloy in the cyclic tensile-compressive tests, and an obvious cyclic hardening is observed;moreover, the ratchetting of the cast AZ91 alloy presented in the cyclic stressing tests depends remarkably on the prescribed mean stress and stress amplitude, but slightly changes with the stress rate, and the evolution of responding peak/valley strain greatly differs from that of wrought Mg alloys and stainless steels. This work provides rich experimental data for establishing the constitutive model of cast Mg alloys.

关键词： Cast magnesium alloy Ratchetting Twinning/detwinning Stress level Stress rate

Improved Wavelet-based Spatial Filter of Damage Imaging Method on Composite Structures

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Chinese Journal of Aeronautics 2011年第5期24卷 665-672页

作者： wang yu yuAN Shenfang QIU lei College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China School of Information and Science Nanjing Audit University Nanjing 210029 China

Piezoelectric sensor array-based spatial filter technology is a new promising method presented in research area of structural health monitoring （SHM） in the recent years. To apply this method to composite structures and give the actual position of damage, this paper proposes a spatial filter-based damage imaging method improved by complex Shannon wavelet transform. The basic principle of spatial filter is analyzed first. Then, this paper proposes a method of using complex Shannon wavelet transform to construct analytic signals of time domain signals of PZT sensors array. The analytic signals are synthesized depending on the principle of the spatial filter to give a damage imaging in the form of angle-time. A method of converting the damage imaging to the form of angle-distance is discussed. Finally, an aircraft composite oil tank is adopted to validate the damage imaging method. The validating results show that this method can recognize angle and distance of damage successfully.

关键词： structural health monitoring composite structures piezoelectric sensors array spatial filter complex Shannon wavelet transform digital signal processing

Tin recovery from a low-grade tin middling with high Si content and low Fe content by reduction–sulfurization roasting with anthracite coal

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International Journal of Minerals,Metallurgy and Materials 2021年第2期28卷 210-220页

作者： Jing-cheng wang lei Li Yong yu State Key Laboratory of Complex Non-ferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction of Ministry of Education Kunming University of Science and TechnologyKunming 650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

A new method for separating and recovering tin from a low-grade tin middling with high Si content and low Fe content by roasting with anthracite coal was researched by studying the reaction mechanism and performing an industrial test,in which the Sn was sulfurized into SnS(g)and then collected using a dust *** Fe–Sn alloy may be formed at roasting temperatures above 950°C,and like the roasting temperature increases,the Sn content and Sn activity in this Fe–Sn alloy ***,more FeS can be formed at higher temperatures and then the formation of FeO–FeS with a low melting point is promoted,which results in more serious sintering of this low-grade tin *** from the thermodynamics and kinetics points of view,the volatilization of the Sn decreases at extremely high roasting *** results of the industrial test carried out in a coal-fired rotary kiln show that the Sn volatilization rate reaches 89.7%and the Sn is concentrated in the collected dust at a high level,indicating that the Sn can be effectively extracted and recovered from the low-grade tin middling with a high Si content and low Fe content through a reduction–sulfurization roasting process.

关键词： low-grade tin middling tin recovery roasting process Fe-Sn alloy resource recycling

Mkate2转化过的大肠埃希氏菌制备的急性肾盂肾炎小鼠模型

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实验动物科学 2017年第1期34卷 16-19页

作者：雷雨王光强朱德生北京大学实验动物中心北京100871 山东大学齐鲁医院呼吸内科济南250012

目的在普通实验环境下通过向肾皮质内注射1×10~7cfu/m L的Mkate2转化非致病性大肠杆菌法,成功制备了急性肾盂肾炎小鼠模型。方法采用影像学方法对模型制作效果进行监测,提高了模型制作的成功率,减少了动物的使用数量。结果成功制备了... 详细信息

目的在普通实验环境下通过向肾皮质内注射1×10~7cfu/m L的Mkate2转化非致病性大肠杆菌法,成功制备了急性肾盂肾炎小鼠模型。方法采用影像学方法对模型制作效果进行监测,提高了模型制作的成功率,减少了动物的使用数量。结果成功制备了小鼠肾盂肾炎模型,同时该细菌没有在肾脏中持续增殖,大大降低了模型制作的生物学风险。

关键词： Mkate2转染过的大肠杆菌肾盂肾炎模型红色荧光

2 - 13 Yield of X-ray Production of Al Bombard by H＋

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IMP & HIRFL Annual Report 2010年第1期 52-52页

作者： Sun yuanbo Zhao Yongtao wang yuyu Cheng Rui Zhou Xianming lei yu wang Xing Xu Ge Xiao Guoqing

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半实物仿真技术在流星突发通信中的应用

无线电工程 2017年第1期47卷 16-18页

作者：于晓磊王昕羽宋建明侯静中国电子科技集团公司第五十四研究所河北石家庄050081 西北工业大学电子信息学院陕西西安710072

针对网络仿真工具在流星突发组网协议仿真方面的不足,提出了应用OPNET的SITL模块来构建流星突发组网协议仿真平台的设计。根据系统在环原理,对包从虚拟到真实和从真实到虚拟的过程进行了分析,并针对流星突发通信信道和流星突发通信网协... 详细信息

针对网络仿真工具在流星突发组网协议仿真方面的不足,提出了应用OPNET的SITL模块来构建流星突发组网协议仿真平台的设计。根据系统在环原理,对包从虚拟到真实和从真实到虚拟的过程进行了分析,并针对流星突发通信信道和流星突发通信网协议的特殊性,对流星突发通信网采用OPNET软件进行建模仿真,实现了物理设备和OPNET仿真网络的互联。完成了仿真实验并收集了网络中数据包的传输时延和信息通过量,仿真结果表明,半实物仿真平台对流星突发通信网的仿真真实、可信。

关键词： SITL 半实物仿真流星突发通信 OPNET仿真建模