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Thermal stability of nanograins with grain boundary relaxation in microalloyed Cu-Sb and Cu-Fe

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Journal of Materials Science & Technology 2023年第24期155卷 66-71页

作者： R.J. zhu X.Zhou X.y. Li Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China

Grain refinement into nanoscale significantly enhances the strength and hardness of metallic materials but generally reduces the thermal stability by the introduced strong tendency for grain boundary(GB)*** nanograins through GB relaxation had been proven as an effective way in several metals recently when the grain size is below a critical ***,we discovered that the abnormally enhanced thermal stability induced by GB relaxation can be realized in 0.5%Sb or Fe doped Cu,similar to that in pure *** observed critical grain sizes for GB relaxation in the two Cu alloys are almost the same as pure ***,the GB relaxation effect on thermal stability is kind of suppressed compared to pure Cu with similar grain sizes because of the segregation/precipitation of Sb/Fe during the annealing process,which accelerates the detwinning and the failure of relaxed GBs.

关键词： Thermal stability Grain boundary relaxation Nanograined Cu alloy Segregation Precipitate

AMPK interacts with DSCAM and plays an important role in Netrin-1 induced neurite outgrowth

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Protein & Cell 2013年第2期4卷 155-161页

作者： Kun zhu Xiaoping Chen Jianghong Liu Haihong ye Li zhu Jane y.Wu State Key Laboratory of Brain and Cognitive Science Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Department of Neurology Center for Genetic MedicineLurie Cancer CenterNorthwestern University Feinberg School of MedicineChicagoIL 60611USA

Down syndrome cell adhesion molecule(DSCAM)acts as a netrin-1 receptor and mediates attractive response of axons to netrin-1 in neural ***,the signaling mechanisms of netrin-DSCAM remain *** we report that AMP-activated protein kinase(AMPK)interacts with DSCAM through itsγsubunit,but does not interact with DCC(deleted in co-lorectal cancer),another major receptor for ***-treatment of cultured cortical neurons leads to increased phosphorylation of *** AMPK mu-tant with dominant-negative effect and AMPK inhibitor can significantly suppress netrin-1 induced neurite ***,these findings demonstrate that AMPK interacts with DSCAM and plays an important role in netrin-1 induced neurite *** study uncovers a previously unknown component,AMPK,in netrin-DSCAM signaling pathway.

关键词： AMP-activated protein kinase(AMPK) neurite outgrowth Down syndrome cell adhesion molecule(DSCAM) netrin

Application of Wenner Configuration to Estimate Soil Water Content in Pine Plantations on Sandy Land

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Pedosphere 2007年第6期17卷 801-812页

作者： zhu Jiao-Jun KANG Hong-Zhang y. GONDA Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China）. Graduate School Chinese Academy of Sciences Beijing 100039 （China） Shanghai Jiaotong University Shanghai 200240 （China） Faculty of Agriculture Niigata University Niigata 950-2181 （Japan）

To estimate the mean value of surface soil water content rapidly,accurately.and nonintrusively,field investigations on soil electrical resistivity(SER)with the yokogawa 324400 earth resistivity meter and the surface(0-150 cm)soil water content(SWC)with time domain reflectometry(TDR),together with the abiotic factors including soil texture,structure. and salinity concentrations were conducted in the Mongolian pine(Pinus sylvestris ***)plantations on a sandy *** measurement of SER was based on the 4-probe Wenner configuration *** between the values of SWC and SER were obtained based on analysis of the abiotic factors of the research site,which play a key role in affecting the soil electrical *** indicate that the SER meter could be used to estimate the mean value of SWC in the Mongolian pine plantations on the sandy land during the growing *** bulky nature of the equipment simplified the cumbersome measurements of soil water content with the general *** must be noted that the Wenner configuration method could only provide the mean values of the SWC,and the soil texture,structure, temperature,and solute concentrations influenced the SER and further affected the estimation of the SWC by the SER ***,the results of this study could be applied on a sandy land during the growing seasons ***, the SWC of other soil types also may be obtained according to the individual soil types using the procedures of this study.

关键词： Mongolian pine plantation sandy land soil electrical resistivity soil water content Wenner configuration method

Nanophase Decomposition of a Zn-Al Based Alloy Zn_(68)Al_(10)Cu_(22)

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Journal of Materials Science & Technology 2004年第6期20卷 687-690页

作者： y.H.zhu W.B.Lee S.To Advanced Materials Research Center Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong ChinaAdvanced Materials Research Center Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong ChinaAdvanced Materials Research Center Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong China

The nanostructural evolution and phase transformation of the films of a Zn-Al based alloy (Zn68Al10Cu22 in wt pct) have been studied by using X-ray diffraction and scanning electron microscopy. Nanostructural thin films of the Zn-AI based alloy were produced by using an electron beam deposition technique. It was found that a nanocrystalline phase η'n had a strong preferred crystal orientation at (0002) crystal planes in the as-deposited films. During ageing at 220℃, the decomposition of nanophase η'n started with clustering to form Z-zones, and transitionai phase, which was accompanied by.an eutectoid decomposition of the η'n phase: η'n β'eut T'. Decomposition, such as clustering and the formation of the Z-zones, and the transitionai phase etc. were observed in the nanophase β'eut. The formation and the decomposition of the transitionai phase of micrometers in size were involved in the decomposition of the main nanophase η'n. The mechanism of the Z-zones formation and the stability of nanophases were discussed.

关键词： Ageing Nanostructure Nanophase stability Zn-Al based alloy film

Magnetohydrodynamic flows tuning in a conduit with multiple channels under a magnetic field applied perpendicular to the plane of flow

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Journal of Hydrodynamics 2017年第2期29卷 332-343页

作者： y.Luo C.N.Kim M.Q.zhu Department of Mechanical Engineering Graduate SchoolKyung Hee UniversityYong-inKorea Department of Mechanical Engineering College of EngineeringKyung Hee UniversityYong-inKorea

In this study, three-dimensional liquid-metal magnetohydrodynamic flows in a conduit with multiple channels under a uniform magnetic field are numerically investigated. The geometry of the conduit is of a four-parallel-channels system including one inflow channel and three outflow channels. The liquid-metal flows into the inflow channel, then turns through 180° in the transi- tion segment, finally flows into three different outflow channels. This kind of channel system can induce counter flow and co-flow, which is rarely investigated before though the conceptual designs of duct flow in the blanket have suggested this type of flow. A structured grid system is chosen after a series of mesh independence tests in the present study. The axial velocity in the side layer near the first partitioning wall, located between the inflow channel and the first outflow channel, is the highest with the lowest electric potential formed therein. The pressure almost linearly decreases in the main flow direction, except in the transition segment. Moreover, the pressure gradient in the first outflow channel is the largest among the three outflow channels. The interdependency of the current, fluid velocity, pressure, electric potential is examined in order to describe the electromagnetic characteristics of the liquid-metal flows.

关键词： Liquid-metal magnetohydrodynamics multiple channels

Gradient Structured Copper by Rotationally Accelerated Shot Peening

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Journal of Materials Science & Technology 2017年第7期33卷 758-761页

作者： X.Wang y.S.Li Q.Z.ang y.H.Zhao y.T.zhu Nano Structural Materials Center School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China Department of Materials Science and Engineering North Carolina State University Raleigh NC 27695 USA

A new technology-rotationally accelerated shot peening（RASP）, was developed to prepare gradient structured materials. By using centrifugal acceleration principle and large steel balls, the RASP technology can produce much higher impact energy compared to conventional shot peening. As a proof-of-concept demonstration, the RASP was utilized to refine the surface layer in pure copper（Cu） with an average grain size of 85 nm. The grain size increases largely from surface downwards the bulk, forming an800 ？m thick gradient-structured surface layer and consequently a micro-hardness gradient. The difference between the RASP technology.and other established techniques in preparing gradient structured materials is discussed. The RASP technology exhibits a promoting future for large-scale manufacturing of gradient materials.

关键词： Microstructure Rotationally accelerated shot peening Gradient structure Hardness Copper

Leader-follower: Human-centered intention-guided controller for novel SuperLimb with application to load-carrying scenarios

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Science China Technological Sciences 2025年第1期 325-338页

作者： Qinghua ZHANG Xianglong LI Hongwei JING Kerui SUN y.ancheng LI Sikai ZHAO Lele LI Haotian JU Ziqi WANG Rui WU Tianjiao ZHENG Jie ZHAO yanhe zhu The State Key Laboratory of Robotics and System Harbin Institute of Technology The Learning Algorithms and Systems Laboratory School of Engineeringécole Polytechnique Fédérale de Lausanne

Supernumerary robotic arms(SuperLimb) are a new type of wearable robot that works closely with humans as a third hand to augment human operation capability. Accurate conveyance of wearers' intentions, allocation of roles, and humancentered interaction considerations are the key points in the process of human–SuperLimb collaboration. This paper proposes a human-centered intention-guided leader–follower controller that relies on the dynamic modeling of SuperLimb with application to load-carrying scenarios. The proposed leader–follower controller takes the human as the leader and the SuperLimb as the follower, achieving effective information communication, autonomous coordination, and good force compliance between SuperLimb, humans, and the environment under human safety assurance. First, the human–SuperLimb dynamic system is modeled to achieve force interaction with the environment and wearer. Second, to achieve the precise intention extraction of humans, pose data from five visual odometry sensors are fused to capture the human state, the generalized position, the velocity of hands, and the surface electromyography signals from two myoelectric bracelets sensors are processed to recognize the natural hand gestures during load-carrying scenarios by a designed Swin transformer network. Then, based on the real-time distance detection between human and mechanical limbs, the security assurance and force-compliant interaction of the human–SuperLimb system are realized. Finally, the human hand muscle intention recognition, human–robot safety strategy verification,and comparative load-carrying experiments with and without the proposed method are conducted on the SuperLimb *** showed that the task parameters are well estimated to produce more reasonable planning trajectories, and SuperLimb could well understand the wearer's intentions to switch different SuperLimb actions. The proposed sensor-based human–robot communication framework motivates future studies of o

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New solid superbases: potassium nitrate supported on porous materials

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Chinese Science Bulletin 1997年第17期42卷 1493-1494页

作者： zhu, JH Chun, y Wang, y Tu, M Chemistry Department Chemistry & Chemical Engineering College Nanjing University Nanjing China

ACCORDING to Tanabe’s definition, all materials possessing the basic strength （H-） over 26.5 are superbases. However, most of superbases known up to now, including CaO and SrO evacuated at 1173 K, K or Na metal supported on KOH/γ-Al2O3, etc. are extremely sensitive to CO2 or H2O in the atmosphere, which limits their application in industrial scale. In or-

关键词： potassium nitrate supported on porous materials New solid superbases

Stationary Potential Formation and Oscillations in Plasma with Immovable Dust Particles

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Plasma Science and Technology 2005年第1期7卷 2657-2659页

作者： y.Tomita R.Smirnov S.zhu NationalInstituteforFusionScience 322-60roshi-choToki509-5292Japan TheGraduateUniversityforAdvancedStudies 322-60roshi-choToki509-5292Japan InstituteofPlasmaPhysics ChineseAcademyofSciencesHefei230031China

Stationary electrostatic-potential formation in plasma with immovable dustparticles was investigated by using one-dimensional kinetic analysis. It is clarified that thedensity of negatively charged dust particles below the threshold value makes the potential decreasemonoton-ically. When the dust densities are above the threshold, there appears the stationaryoscillation in an electrostatic potential due to the streaming plasma. It is found that thewavelength of this mode is of the order of Debye length. These phenomena are different from those ofthe conventional dust ion-acoustic waves in plasma, where the effect of dust-charging is not takeninto account.

关键词： dust particle stationary potential dust ion-acoustic wave