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Application of Ultrasonic Motor to Control of Moment Gyroscope Gimbal Servo System

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第1期34卷 15-21页

作者： Wu Jintao Pan Song Zhao Lei Wu Dengyun zhang jiyang Beijing Institute of Control Engineering Beijing 100190P.R.China Precision Driving Laboratory Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

Attitude control system is one of the most important subsystems in a *** a key actuator,the control moment gyroscope(CMG)mainly determines the performance of attitude control ***,the control accuracy and output torque smoothness of the CMG depends more on its gimbal servo *** the constraints of size,mass and power consumption for a small satellite,here,a mini-CMG is designed,in which the gimbal servo system is driven by an ultrasonic *** good performances of the CMG are obtained by both the ultrasonic motor and the rotary *** direct drive of gimbal improves its dynamic performance,with the output bandwidth above 20 *** angular and speed closed-loop control obtains the 0.02°/s gimbal rate,and the output torque resolution better than 2×10^(-3) N·*** ultrasonic motor provides 1.0N·m self-lock torque during power-off,with 12arc-second position accuracy.

关键词： control moment gyroscope gimbal servo system ultrasonic motor

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丁苯橡胶发泡材料的制备和性能研究

橡胶工业 2025年第1期72卷 10-17页

作者：胡润林张继阳邹华李伟北京化工大学北京市新型高分子材料制备与加工重点实验室北京100029 北京北化新橡特种材料科技股份有限公司北京100029

研究白炭黑用量、硫黄/过氧化物BIBP并用硫化体系的过氧化物BIBP和助交联剂TAIC用量、发泡倍率、预硫化温度和预硫化时间对丁苯橡胶(SBR)发泡材料性能的影响。结果表明:白炭黑用量增大,SBR发泡材料的100%定伸应力、拉伸强度、静刚度和... 详细信息

研究白炭黑用量、硫黄/过氧化物BIBP并用硫化体系的过氧化物BIBP和助交联剂TAIC用量、发泡倍率、预硫化温度和预硫化时间对丁苯橡胶(SBR)发泡材料性能的影响。结果表明:白炭黑用量增大,SBR发泡材料的100%定伸应力、拉伸强度、静刚度和动静刚度比增大,拉断伸长率减小;随着过氧化物BIBP用量和助交联剂TAIC用量增大,SBR发泡材料的拉伸强度、拉断伸长率、压缩永久变形和动静刚度比减小,100%定伸应力和静刚度增大;随着发泡倍率增大,SBR发泡材料的静刚度减小,动静刚度比增大;预硫化温度为125℃和预硫化时间为16 min时,SBR发泡材料的减振性能最佳,此时泡孔直径较小及分布均匀。

关键词：丁苯橡胶发泡材料静刚度动静刚度比

How to improve superlubricity performance of diketone at steel interface:Effects of oxygen gas

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Friction 2023年第6期11卷 927-937页

作者： Yuanyuan JIANG Lei CHEN Chen XIAO Shumin zhang Chenhui zhang Ningning ZHOU Tao QIN Linmao QIAN jiyang zhang Tribology Research Institute State Key Laboratory of Traction PowerSouthwest Jiaotong UniversityChengdu610031China Technology and Equipment of Rail Transit Operation and Maintenance Key Laboratory of Sichuan Province Southwest Jiaotong UniversityChengdu610031China State Key Laboratory of Tribology Tsinghua UniversityBeijing100084China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing100094China

Achievement of steady and reliable super-low friction at the steel/steel contact interface,one of the most tribological systems applied for mechanical moving parts,is of importance for prolonging machine lifetime and reducing energy *** we reported that the superlubricity performance of the steel/steel sliding interface lubricated with tiny amounts of diketone solution strongly depends on the oxygen content in surrounding *** increase of oxygen not only significantly shortens the initial running-in time but also further reduces the stable coefficient of friction in superlubricity stage due to the enhancement of tribochemical *** the one hand,more severe oxidation wear occurring at higher oxygen content facilitates material removal of the contact interface,lowering the contact pressure and the corresponding initial *** the other hand,the growth of iron ions during the shear process in high oxygen environment promotes the formation of chelate which acted as an effective lubricated film chemisorbed at the steel/steel friction interface to further lower the interfacial *** results provide a new opportunity to further optimize the tribological performance of diketone superlubricity system,especially towards the lubrication of mechanical engineering materials.

关键词： superlubricity oxygen content steel/steel interface diketone chelate

Modeling and Attitude Control of a Tilt Tri-Rotor UAV 36

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Modeling and Attitude Control of a Tilt Tri-Rotor UAV

Water-based superlubricity in vacuum

第36届中国控制会议

作者： Li Yu Daibing zhang jiyang zhang Chongyu Pan National University of Defense Technology College of Mechatronic Engineering and Automation

ISBN: (纸本)9781538629185

The tilt tri-rotor UAV which combines the advantages of both rotary wing and fixed wing vehicle, offers the capability of hover, vertical take-off and landing and fast forward movement. Because of the complex structure and aerodynamics, the modeling and control of tilt tri-rotor UAV reamians a problem. In this paper, precise model of a tilt tri-rotor UAV is developed by combing system identification and physical measurement. An attitude controller is designed based on control allocation of attitude and throttle on the powerplant. The detailed mathematical model is obtained by the equations of Newton-Euler, which parameters are acquired from designed experiments. To improve the stability of helicopter fight, a new control allocation strategy is developed in the framework of PID control.

关键词： VTOL tilt tri-rotor attitude control control allocation

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Friction 2019年第2期7卷 192-198页

作者： Chen XIAO Jinjin LI Lei CHEN Chenhui zhang Ningning ZHOU Tao QING Linmao QIAN jiyang zhang Jianbin LUO Tribology Research Institute State Key Laboratory of Traction PowerSouthwest Jiaotong University State Key Laboratory of Tribology Tsinghua University Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control Engineering

This study achieved water‐based superlubricity with the lubrication of H_3PO_4 solution in vacuum(highest vacuum degree <10–4 torr) for the first time by performing a pre‐running process in air before running in vacuum. The stable water‐based superlubricity was sustainable in vacuum(0.02 torr) for 14 h until the test was stopped by the user for non‐experimental factor. A further analysis suggested that the superlubricity may be attributed to the phosphoric acid–water network formed in air, which can efficiently lock water molecules in the liquid lubricating film even in vacuum owing to the strong hydrogen bond interaction. Such capability to lock water is strongly affected by the strength of hydrogen bond and environmental conditions. The realization of water‐based superlubricity with H_3PO_4 solution in vacuum can lead to its application in space environment.

关键词： friction water-based superlubricity vacuum phosphoric acid

Growth Defects in Langasite Crystals Observed with White Beam Synchrotron Radiation Topography

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Journal of Rare Earths 2006年第z1期24卷 159-161页

作者： Wang Xuping Wang jiyang Hu Xiaobo zhang Jianxiu Zhao Hongyang Huang Wanxia Zhu Peiping State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China Beijing Synchrotron Radiation Laboratory Institute of High Energy Physics Beijing 100039 China Beijing Synchrotron Radiation Laboratory Institute of High Energy Physics Beijing 100039 China

Langasite single crystal was grown by the Czochralski method and its perfection was assessed by white beam synchrotron radiation topography. It is found that the growth core and the growth striations are the primary growth defects and they show strong X-ray kinematical contrast in the topographs. Another typical defect in LGS crystal is dislocation. The formation mechanisms of these growth defects in LGS crystals were discussed.

关键词： Langasite (LGS crystal) growth striation growth core dislocation

Blackening failure of poly-α-olefin impregnated porous polymide due to the splitting of lubrication oil catalyzed by iron

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Friction 2024年第9期12卷 1969-1979页

作者： Pengfei SHI Yang YIN Shaohua zhang Diankai zhang Yuanyuan JIANG Yang WANG Ningning ZHOU Tao QING Jintao WU Linmao QIAN jiyang zhang Lei CHEN Tribology Research Institute State Key Laboratory of Rail Transit Vehicle SystemSchool of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100094China Technology and Equipment of Rail Transit Operation and Maintenance Key Laboratory of Sichuan Province School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Lubrication failure accompanying with blackening phenomenon significantly reduces the long-running operational reliability of porous polymide(PPI)lubricated with poly-α-olefin(PAO)***,the effects of lubrication condition and counter-surface chemistry on the blackening failure of PAO impregnated PPI were studied through the comparison of the tribological tests against GCr15 steel ball and Al_(2)O_(3)ceramic ball with and without PAO oil *** products were found to be formed on the PAO impregnated PPI surface slid against steel ball or Al_(2)O_(3)ball added with iron nano-particles,but be absent under the conditions without iron or PAO *** analysis indicated that the iron-catalyzed splitting of PAO oil into small molecule alkanes and following the formation of black organic matter should be mainly responsible for the blackening *** dynamic(MD)simulations demonstrated that the iron facilitated the separation of hydrogen atom and the following broken of C–C bonds in PAO molecules,final resulting in the splitting of PAO oil.

关键词： porous polyimide poly-α-olefin oil friction-induced blackening phenomenon tribological performance ReaxFF MD simulation

Plasma biomarker screening for liver fibrosis with the N-terminal isotope tagging strategy

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Science China(Life Sciences) 2011年第5期54卷 393-402页

作者： LI ShuLong LIU Xin WEI Lai WANG HuiFen zhang jiyang WEI HanDong QIAN XiaoHong JIANG Ying HE FuChu State Key Laboratory of Proteomics Beijing Proteome Research Center Beijing Institute of Radiation Medicine Beijing 102206 China Beijing Institute of Biotechnology Beijing 100071 China People 's Hospital of Peking University Beijing 100044 China 302 Military Hospital of China Beijing 100039 China Institutes of Biomedical Sciences Fudan University Shanghai 200032 China Central Laboratory Yantai Yu-Huang-Ding Hospital Yantai 264000 China

A non-invasive diagnostic approach is crucial for the evaluation of severity of liver disease,treatment decisions,and assessing drug *** study evaluated plasma proteomic profiling via an N-terminal isotope tagging strategy coupled with liquid chromatography/Fourier transform ion cyclotron resonance mass spectrometry measurement to detect liver fibrosis *** plasma from different liver fibrosis stages,which were assessed in advance by the current gold-standard of liver biopsy,was quantitatively analyzed.A total of 72 plasma proteins were found to be dysregulated during the fibrogenesis process,and this finding constituted a valuable candidate plasma biomarker bank for follow-up *** results of fibronectin by Western blotting reconfirmed the mass-based *** Pathways Analysis showed four types of metabolic networks for the functional effect of liver fibrosis disease in chronic hepatitis B ***,quantitative proteomics via the N-terminal acetyl isotope labeling technique provides an effective and useful tool for screening plasma candidate biomarkers for liver *** quantitatively monitored the fibrogenesis process in CHB *** discovered many new valuable candidate biomarkers for the diagnosis of liver fibrosis and also partly identified the mechanism involved in liver fibrosis *** results provide a clearer understanding of liver fibrosis pathophysiology and will also hopefully lead to improvement of clinical diagnosis and treatment.

关键词： quantitative proteomics fiver fibrosis biomarker plasma hepatitis B virus

Use of stem cell transplantation to treat epilepsy A Web of Science-based literature analysis

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Neural Regeneration Research 2012年第33期7卷 2624-2631页

作者： Zhongmin Yin Yushu Dong jiyang zhang Li Wang Department of Neurosurgery Chinese PLA 463 Hospital Shenyang 110042 Liaoning Province China Department of Rehabilitation Third Affiliated Hospital of Liaoning Medical University Jinzhou 121000 Liaoning Province China

OBJECTIVE： To identify global research trends in the use of stem cell transplantation to treat epilepsy. DATA RETRIEVAL： We performed a bibliometric analysis of studies on the use of stem cell transplantation to treat epilepsy during 2002–2011, retrieved from Web of Science, using the key words epilepsy or epileptic or epilepticus or seizure and ＂stem cell＂. SELECTION CRITERIA： Inclusion criteria：（a） peer-reviewed published articles on the use of stem cell transplantation to treat epilepsy indexed in Web of Science; （b） original research articles, reviews, meeting abstracts, proceedings papers, book chapters, editorial material, and news items. MAIN OUTCOME MEASURES：（a） Annual publication output; （b） type of publication; （c） publication by research field; （d） publication by journal; （e） publication by author; （f） publication by country and institution; （g） publications by institution in China; （h） most-cited papers; and （i） papers published by Chinese authors or institutions. RESULTS： A total of 460 publications on the use of stem cell transplantation to treat epilepsy were retrieved from Web of Science, 2002–2011. The number of publications gradually increased over the 10-year study period. Articles and reviews constituted the major types of publications. More than half of the studies were in the field of neuroscience/neurology. The most prolific journals for this topic were Epilepsia, Bone Marrow Transplantation, and Journal of Neuroscience. Of the 460 publications, almost half came from American authors and institutions; relatively few papers were published by Chinese authors or institutions. CONCLUSION： Literature on stem cell transplantation for epilepsy includes many reports of basic research, but few of clinical trials or treatments. Exact effects are not yet evaluated. Epilepsy rehabilitation is a long-term, complex, and comprehensive system engineering. With advances in medical development, some effective medical, social and educational measures are neede

关键词： epilepsy seizure hippocampus stem cell ancestral cell neurons neurogenesis central nervoussystem brain bibliometric neural regeneration