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Impact Fretting Wear Behavior of Alloy 690 Tubes in Dry and Deionized Water Conditions

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 819-828页

作者： Zhen-Bing Cai Jin-Fang Peng Hao Qian Li-Chen Tang Min-Hao Zhu Traction Power State laboratory Southwest Jiaotong University Chengdu 610031 China Shanghai Nuclear Engineering research and Design Institute Shanghai 200233 China

The impact fretting wear has largely occurred at nuclear power device induced by the flow-induced vibra- tion, and it will take potential hazards to the service of the equipment. However, the present study focuses on the tangential fretting wear of alloy 690 tubes. research on impact fretting wear of alloy 690 tubes is limited and the related research is imminent. Therefore, impact fretting wear behavior of alloy 690 tubes against 304 stainless steels is investigated. Deionized water is used to simulate the flow environment of the equipment, and the dry envi- ronment is used for comparison. Varied analytical tech- niques are employed to characterize the wear and tribochemical behavior during impact fretting wear. Char- acterization results indicate that cracks occur at high impact load in both water and dry equipment; however, the water as a medium can significantly delay the cracking time. The crack propagation behavior shows a jagged shape in the water, but crack extended disorderly in dry equip- ment because the water changed the stress distribution and retarded the friction heat during the wear process. The SEM and XPS analysis shows that the main failure mechanisms of the tube under impact fretting are fatiguewear and friction oxidation. The effect of medium（water） on fretting wear is revealed, which plays a potential and promising role in the service of nuclear power device and other flow equipments.

关键词： Impact fretting wear Alloy 690 Oxidativewear Crack Fracture appearance

Fusion power supply advances by the J-TEXT engineering team

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Plasma Science and Technology 2022年第12期24卷 85-100页

作者： Ming ZHANG Hongqi ZHANG Rumeng WANG Xiaohan XIE Wenshan WANG Yixing JIANG Zhiheng LI Peilong ZHANG Liye WANG Shaoxiang MA Yong YANG Wei ZHENG Bo RAO International Joint research laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and Technology and School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China

To meet the stringent requirements of the fusion power supply for large-scale fusion devices,the J-TEXT engineering team has carried out key technology research and applications in several important directions of fusion power *** article presents the advances made by the J-TEXT engineering team in recent years in the following areas:(1) a high-voltage power supply for an auxiliary heating system;(2) a breakdown protection device for an auxiliary heating power supply;(3) magnetic field compatibility;(4) a high-voltage pulsed power supply for a fieldreversed configuration;(5) a large physics experimental facility control *** research backgrounds,technical progress,test results,applications,summaries and prospects are described in detail in each *** innovative research results and valuable engineering experience can promote the progress of fusion power supply technology,and also lay a foundation for the development of power supplies with higher parameters in the future.

关键词： high-voltage DC power supply breakdown protection magnetic field compatibility high-voltage pulsed power supply control system

AIEgen based light-up probes for live cell imaging

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Science China Chemistry 2016年第1期59卷 53-61页

作者： Jing Liang Guangxue Feng Ryan Tsz Kin Kwok Dan Ding Benzhong Tang Bin Liu Department of Chemical and Biomolecular Engineering National University of Singapore4 Engineering Drive 4117585Singapore NUS Environmental research Institute National University of Singapore5A Engineering Drive 1117411Singapore Department of Chemistry Division of Biomedical Engineeringthe Hong Kong University of Science and TechnologyKowloonHong KongChina SCUT-HKUST Joint research laboratory Guangdong Innovative Research TeamState Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou 510640China Institute of Materials research Engineering Agency for ScienceTechnology and Research3 Research Link117602Singapore

Fluorescent light-up probes comprising a tetraphenylethene unit with aggregation-induced emission(AIE)characteristics and a water-soluble peptide have been designed and synthesized which provide cell membrane and nuclear permeability to live *** strategy has offered new opportunities for the development of probes with light-up ability and good signal-to-noise *** selectivity or targeting specificity is determined by the peptide sequence,i.e.a nuclear localization signal that leads to nucleus imaging and a cell biomarker targeting peptide that offers specific light-up imaging of HT-29 cells.

关键词： aggregation-induced emission(AIE) light-up probe live cell imaging nucleus imaging targeted cell imaging AIE probes

Cellular arsenic transport pathways in mammals

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Journal of Environmental Sciences 2016年第11期28卷 38-58页

作者： Barbara A.Roggenbeck Mayukh Banerjee Elaine M.Leslie Department of Physiology and Membrane Protein Disease research Group University of Alberta Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and Pathology University of Alberta

Natural contamination of drinking water with arsenic results in the exposure of millions of people world-wide to unacceptable levels of this metalloid. This is a serious global health problem because arsenic is a Group 1（proven） human carcinogen and chronic exposure is known to cause skin, lung, and bladder tumors. Furthermore, arsenic exposure can result in a myriad of other adverse health effects including diseases of the cardiovascular,respiratory, neurological, reproductive, and endocrine systems. In addition to chronic environmental exposure to arsenic, arsenic trioxide is approved for the clinical treatment of acute promyelocytic leukemia, and is in clinical trials for other hematological malignancies as well as solid tumors. Considerable inter-individual variability in susceptibility to arsenic-induced disease and toxicity exists, and the reasons for such differences are incompletely understood. Transport pathways that influence the cellular uptake and export of arsenic contribute to regulating its cellular, tissue, and ultimately body levels. In the current review, membrane proteins（including phosphate transporters, aquaglyceroporin channels, solute carrier proteins, and ATP-binding cassette transporters） shown experimentally to contribute to the passage of inorganic, methylated, and/or glutathionylated arsenic species across cellular membranes are discussed. Furthermore, what is known about arsenic transporters in organs involved in absorption, distribution, and metabolism and how transport pathways contribute to arsenic elimination are described.

关键词： Arsenic Glutathione Cellular uptake Cellular efflux Transport

Physical Properties and Electrochemical Performance of LiNi_xMn_(2-x)O_4 Cathode Materials Prepared using a Precipitation Method

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Journal of Materials Science & Technology 2006年第1期22卷 19-24页

作者： Guoguang WAN Jianming WANG Wenqu MAO Jianqing ZHANG Chunan CAO Department of Chemistry Zhejiang University Hangzhou 310027 China State Key laboratory for Corrosion and Protection Institute of Metal Research CAS Shenyang 110016 China

To improve the cycle performance of spinel LiMn204 as the cathode material of 4 V class Li secondary batteries, LiNixMn2-xO4 （x=0-0.3） samples were prepared using a simple precipitation method, and the effects of Ni doping on the physical properties and electrochemical performance of the samples were investigated using various methods. All LiNixMn2-xO4 （x=0-0.3） compounds show a single spinel phase, and the lattice parameter （a）, the unit cell volume （v） and particle size decrease with increasing Ni content. The results of the electrochemical experiments showed that the initial charge-discharge capacity of LiNixMn2-xO4 samples in the 3.0-4.4 V range decreases with increasing Ni content except for pure LiMn2O4; however, the capacity in the 4.4-4.9 V range increases with the increasing Ni content. For spinel samples Ni substitution can contribute to the improvement of their cycle performance due to the formation of the stronger Ni-O bond, homogeneous morphology, and sub-micron sized particles, and the sample with x=0.05 has larger peak currents, higher initial capacity and better cycling capability due to its lower electrochemical and diffusion polarization than those of other samples.

关键词： Ni-substituted LiMn2O4 Electrochemical performance Electrochemical impedance spectroscopy

Control of Antagonistic McKibben Muscles via a Bio-inspired Approach

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Journal of Bionic Engineering 2022年第6期19卷 1771-1789页

作者： Xinyi Chen Wenxin Zhu Wenyu Liang Yilin Lang Qinyuan Ren State Key laboratory of Industrial Control Technology Zhejiang University310027HangzhouZhejiangChina Institute for Infocomm research A^(*)STAR138632SingaporeSingapore

McKibben muscles are increasingly used in many robotic applications due to their advantages of lightweight,compliant,and skeletal muscles-like ***,there are still huge challenges in the motion control of McKibben muscles due to the system nonlinearity(e.g.,hysteresis)and model *** investigate the control issues,a soft artificial arm actuated by an antagonistic pair of McKibben muscles,mimicking the biological structure of skeleton-muscle systems,is *** by the biological motor control capability that humans can control and coordinate a group of muscles to achieve complex motions,a cerebellum-like controller based on Spiking Neural Networks(SNNs)is employed for the motion control of the developed artificial *** from the employment of the SNN-based cerebellar model,the proposed control scheme provides online adaptive learning capability,good computational efficiency,fast response,and strong ***,several simulations and experiments are conducted subject to different environmental *** simulation and experimental results verify that the proposed method can achieve good tracking performance,adaptability,and strong robustness.

关键词： McKibben muscle Cerebellum-like controller Spiking Neural Network Soft artificial arm Adaptive control

Sealing Performance of Pressure-Adaptive Seal

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Journal of Shanghai Jiaotong university(Science) 2022年第6期27卷 747-756页

作者： LI Yuanfeng WANG Yiling ZHANG Wanxin LIU Jinian MA Jialu National Key laboratory of Human Factors Engineering China Astronaut Research and Training CenterBeijing 100094China

A pressure-adaptive seal is developed to meet the demands of quick assembling and disassembling for an individual protection equipment in *** analysis model,which reflects the main characteristics of the seal structure,is built based on the finite element method and the Roth’s theory of rubber seal,and verified by the prototype *** influences of precompression ratio,hardness of the sealing ring rubber,and friction coefficient on the sealing performance are investigated by variable parameter *** show that the model can describe the essential characteristics of the pressure-adaptive seal structure,which has good follow-up to the cavity pressure to achieve the purpose of pressure *** leakage rate correlates negatively with the precompression ratio of the sealing ring and the hardness of the sealing ring material,while is positively related to the friction coefficient between the sealing ring and the sealing *** maximum contact stress on sealing surface has negative correlation with the precompression ratio of the sealing ring,and positive correlation with the hardness of the seal ring *** damage risk of the sealing ring increases with the increases of the precompression ratio of sealing ring,hardness of sealing ring material,and friction coefficient.

关键词： pressure-adaptive seal contact stress leakage rate

Influence of order-disorder transition on the mechanical andthermophysical properties of ABOhigh-entropy ceramicsInfluence of order-disorder transition on the mechanical and thermophysical properties of A_(2)B_(2)O_(7)high-entropy ceramics 1

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Journal of Advanced Ceramics 2022年第8期11卷 1222-1234页

作者： Jiatong ZHU Mingyue WEI Jie XU Runwu YANG Xuanyu MENG Ping ZHANG Jinlong YANG Guangzhong LI Feng GAO State Key laboratory of Solidification Processing MIIT Key Laboratory of Radiation Detection Materials and DevicesSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China NPU–QMUL Joint research Institute of Advanced Materials and Structure Northwestern Polytechnical UniversityXi’an 710072China State Key laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China State Key laboratory of Porous Metal Materials Northwest Institute for Nonferrous Metal ResearchXi’an 710016China

The order–disorder transition(ODT)of A_(2)B_(2)O_(7)compounds obtained enormous attention owing to the potential application for thermal barrier coating(TBC)*** this work,the influence of ODT on the mechanical and thermophysical properties of dual-phase A_(2)B_(2)O_(7)high-entropy ceramics was investigated by substituting Ce^(4+)and Hf^(4+)with different ionic radii on B-sites(Zr^(4+)).The X-ray diffraction(XRD),Raman,and transmission electron microscopy(TEM)results show that rA3+/rB^(4+)=1.47 is the critical value of ODT phase boundary with different doping B-site ion contents,and the energy dispersive spectroscopy(EDS)results further indicate the uniform distribution of ***,owing to the high intrinsic disorder derived from high-entropy effect,the A_(2)B_(2)O_(7)high-entropy ceramics exhibit unreduced modulus(E0≈230 GPa)and enhanced mechanical properties(HV≈10 GPa,KIC≈2.3 MPa·m^(0.5)).A_(2)B_(2)O_(7)high-entropy ceramics exhibit excellent thermal stability with relatively high thermal expansion coefficients(TECs)(Hf_(0.25),11.20×10-6 K-1,1000℃).Moreover,the matching calculation implied that the ODT further enhances the phonon scattering coefficient,leading to a relatively lower thermal conductivity of(La_(0.25)Eu_(0.25)Gd_(0.25)Yb_(0.25))2(Zr_(0.85)Ce_(0.15))_(2)O_(7)(1.48–1.51 W/(m·K),100–500℃)compared with other *** present work provides a novel composition design principle for high-entropy ceramics,as well as a material selection rule for high-temperature insulation applications.

关键词： high-entropy ceramics A_(2)B_(2)O_(7) order-disorder transition(ODT) mechanical properties thermal conductivity

Effect of Ti-Mg-Ca treatment on properties of heat-affected zone after high heat input welding

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Journal of Iron and Steel research International 2019年第5期26卷 501-511页

作者： Hao-nan Lou Chao Wang Bing-xing Wang Zhao-dong Wang R.D.K. Misra State Key laboratory of Rolling and Automation Northeastern University Shenyang 110819 Liaoning China laboratory for Excellence in Advanced Steels research Department of Metallurgical Materials and Biomedical Engineering University of Texas at EI Paso EI Faso 79968 TX USA

The combined influence of Mg and Ca treatment on the properties of heat-affected zone (HAZ) of low-carbon steel after high heat input welding was systematically studied. Experimental steels deoxidized with different elements were prepared, i.e., C-Mn steel with Al, Ti-Ca steel with Ti and Ca, Ti-Mg-Ca steel with Ti, Mg and Ca. Results showed that the inclusions in C-Mn steel were mainly Al2O3 and MnS with low density and large size. However, the average size was refined to only ~0.34 μm in Ti-Mg-Ca steel and the amount increased remarkably. Microstructure of simulated HAZ for 200 kJ/cm changed from ferrite side plates or upper bainite to acicular ferrite after treatment with Ti, Mg and Ca. Ca addition decreased the strain field around inclusions and enhanced the ability of acicular ferrite nucleation. In situ observation of Ti-Mg-Ca steel showed that the movement of austenite grain boundaries was retarded and nucleation sites of acicular ferrite were greater than Ti-Ca steel because of Mg addition. Impact energy of HAZ at — 40℃ was increased from 7 to 232 J and showed excellent stability because of Ti-Mg-Ca treatment. High volume fraction of acicular ferrite acted as obstacles toward cleavage cracks.

关键词： Heat-affected zone Microstructure Strain field Impact energy Ca-Mg treatment