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A cceleration of Ionospheric Out-Flowing Ions in the Substorm in Geo-magnetotail

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Chinese Physics letters 1999年第12期16卷 908-910页

作者： SHI Jian-kui lIU Zhen-Xing t.l.zhang K.torkar Center for Space Science&Applied Research Chinese Academy of SciencesBeijing 100080 Space Research Institute Austrian Academy of SciencesA-8010 GrazAustria

Using dynamics equation, acceleration of out-flowing ion during dipolarization in a substorm in the magneto-tail is simulated. the main results show that: (1) the ion distribution function that is initially exponentially decreasing with increasing speed is turned into a single peak distribution, and with time the peak moves towards higher speed. (2) the peak moves along V⊥ faster than that along V||, and the ion acceleration mainly occurs in the middle of the dipolarization. (3) the higher the initial energy, the faster the peak moves, and the more energy is obtained by the ions. the ion energy theoretically calculated is as high as about 102 keV, this is consistent with the observation.

关键词： storm faster acceleration

Nanostructured steels for advanced structural applications

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Materials Futures 2022年第1期1卷 97-100页

作者： H J Kong t Yang t l zhang B X Cao C t liu Department of Mechanical Engineering Department of Material Science and EngineeringHong Kong Institute for Advanced StudyCity University of Hong KongHong KongPeople’s Republic of China

this vision summarizes the recent advancement of nanostructured steels foradvanced structural applications, foresees possible challenges and pinpoints futuredirections as well as opportunities in this new era of indus... 详细信息

关键词： nanostructured steels extreme environments advanced manufacturing shape memory

Properties of Field Aligned Current in Plasma Sheet Boundary layers in Magnetotail： Cluster Observation

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Chinese Physics letters 2009年第2期26卷 304-306页

作者：史建魁程征伟 t. l. zhang M. Dunlop 刘振兴 State Key laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 Space Research Institute Austrian Academy of Sciences Graz Austria SStD Rutherford Appleton Laboratory Chilton Didcot UK

Field aligned current （FAC） distribution in the plasma sheet boundary layers （PSBls） in the magnetotail is studied statistically by analysing magnetic field data from the Cluster 4-point measurements. the results show that the FAC distribution on the dusk side is not the same as that on the dawn side in the magnetotail. On the each side earthward and tailward, FA C occurrences are different; occurrence and average current density of FA Cs in the northern hemisphere are different from those in the southern hemisphere. this implies that the FACs have dusk-dawn side asymmetry, polarity asymmetry and inter hemisphere difference in the magnetotail. the present results give a good observation evidence for study on the FAC mechanism.

关键词： field emission molybdenum dioxide enhancement factor

Dynamic mechanical relaxation behavior of Zr_(35)Hf_(17.5)ti_(5.5)Al_(12.5)Co_(7.5)Ni_(12)Cu_(10)high entropy bulk metallic glass

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Journal of Materials Science & technology 2021年第24期83卷 248-255页

作者： l.t.zhang Y.J.Duan t.Wada H.Kato J.M.Pelletier D.Crespo E.Pineda J.C.Qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China Institute for Materials Research Tohoku UniversitySendai980-8577Japan Universitéde lyon MATEISUMR CNRS5510Bat.B.PascalINSA-LyonF-69621Villeurbanne CedexFrance Department of Physics Barcelona Research Center in Multiscale Science and TechnologyInstitute of Energy TechnologiesUniversitat Politècnica de Catalunya08019BarcelonaSpain

Non-equiatomic high entropy bulk metallic glasses were reported recently and show unique mechanical and physical *** mechanical relaxation behavior of Zr_(35)Hf_(17.5)ti_(5.5)Al_(12.5)Co_(7.5)Ni_(12)Cu_(10)high entropy bulk metallic glass was investigated by dynamic mechanical analysis(DMA)and the mechanical spectra could be well described by the quasi-point defects(QPD)*** to typical metallic glasses,the intensity of theβrelaxation of Zr_(35)Hf_(17.5)ti_(5.5)Al_(12.5)Co_(7.5)Ni_(12)Cu_(10)high entropy bulk metallic glass is lower due to the sluggish *** the same time,the correlation factor is higher than that of conventional metallic glasses and this is ascribed to the high configuration *** parallel,physical aging below the glass transition temperature leads to a decrease of atomic mobility,caused by a decrease of the concentration of defects.

关键词： High entropy bulk metallic glass Mechanical relaxation Quasi-point defects Physical aging

Analysis of the anelastic deformation of high-entropy Pd_(20)Pt_(20)Cu_(20)Ni_(20)P_(20) metallic glass under stress relaxation and recovery

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Journal of Materials Science & technology 2022年第12期107卷 82-91页

作者： Y.J.Duan l.t.zhang t.Wada H.Kato E.Pineda D.Crespo J.M.Pelletier J.C.Qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China Department of Physics Institute of Energy TechnologiesUniversitat Politècnica de CatalunyaBarcelona 08019Spain Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Universitéde lyon MATEISUMR CNRS5510Bat.B.PascalINSA-LyonF-69621 Villeurbanne CedexFrance

the anelastic deformation behavior of Pd_(20)Pt_(20)Cu_(20)Ni_(20)P_(20) high-entropy metallic glass was probed by monitoring the stress relaxation and recovery processes. the stress relaxation under consecutive strain steps can be described by the Kohlrausch-Williams-Watts(KWW) function. In addition, considering a hierarchy of relaxation processes related to the structural heterogeneity, a constitutive model is proposed in order to describe the whole process of stress relaxation and determine the contribution of different time scales. Moreover, a crossover from stochastic activation to percolation of flow defects with the ultimate strain can be observed during stress relaxation process. the anelastic recovery process after a strain step is studied as a function of the initial strain level and characterized by means of a direct spectrum analysis. the peaks in the recovery time-spectra revealed the evolution of flow defects in Pd_(20)Pt_(20)Cu_(20)Ni_(20)P_(20) high-entropy metallic glass. the understanding of the atomic free-volume zones effect and the anelastic deformation provides important insight into how atomic structural features affect the deformation behavior of high-entropy metallic glasses, and may provide a new avenue into the improvement of their mechanical properties.

关键词： High-entropy metallic glass Stress relaxation Anelastic deformation Flow defects Free-volume zones

Pc5 Oscillation Analysis by the Satellite and Ground-Based Data

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空间科学学报 2005年第5期25卷 393-396页

作者： A. Potapov t. Polyushkina t. l. zhang H. Zhao A. Guglielmi J. Kultima Institute of Solar-terrestrial Physics Siberia Branch Russian Academy of Sciences Irkutsk 664033 Russia Space Research Institute Austrian Academy of Sciences Graz Austria National Microwave Remote Sensing laboratory Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China Institute of Physics of the Earth Russian Academy of Sciences Moscow 123995 Russia Sodankylii Geophysical Observatory Sodankylii Finland

large amplitude Pc5 event was observed in the space and on ground on August 3, 2001, about three hours after contact of the strong discontinuity in the solar wind with the magnetosphere according to data from ACE and Wind satellites. the Pc5 amplitude was as high as 15 nt in the tail of magnetosphere and about 5 nt at the ground based stations. In the magnetosphere Pc5 waves were observed by Cluster and Polar satellites, which occupied positions in the morning part of the near tail at the close field lines but were parted by distance of 11.5 Re, mainly along the x-axis of the GSM coordinate system. Both compressional and transverse components of the Pc5 wave activity were observed in the space, with the transverse component having the larger amplitude. time delay between the Cluster and Polar satellites was about 8 minutes, which could be interpreted as a wave propagation from the geomagnetic tail to the Earth with the 150km/s group *** ground-based Pc5 activity was analysed by using data from the Image magnetometer network. Doubtless demonstrations of a field line resonant structure were found in variations of amplitude and polarization with latitude. Finnish chain of search coil magnetometers observed modulated Pc1 emission simultaneously with the Pc5 wave train. A possibility of non-linear impact of Pc5 wave energy on the plasma and waves in the magnetosphere is discussed.

关键词：人造卫星磁气圈太阳风太阳活动

Achieving ultrahigh strength and ductility in high-entropy alloys via dual precipitation

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Journal of Materials Science & technology 2023年第35期166卷 67-77页

作者： J.M.Guo B.C.Zhou S.Qiu H.J.Kong M.C.Niu J.H.luan t.l.zhang H.Wu Z.B.Jiao Department of Mechanical Engineering Research Institute for Advanced ManufacturingThe Hong Kong Polytechnic UniversityHong KongChina the Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518057China Department of Materials Science and Engineering City University of Hong KongHong KongChina State Key laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

the strength-ductility trade-offhas been a longstanding dilemma in metallic *** we report an innovative approach to achieve a high strength-ductility synergy via dual precipitation of sheared and bypassed precipitates.(Ni_(2) Co_(2) FeCr)_(96-x) Al_(4) Nb_(x)(at.%)alloys strengthened by nanoscale l12 particles and laves precipitates were selected as a model for this study,and their precipitate microstructures and mechanical properties were thoroughly *** dual-precipitation-strengthened alloys exhibit a yield strength of more than 1400 MPa,an ultimate tensile strength of over 1800 MPa,and a uniform elon-gation of 18%,thus achieving a high strength-ductility *** analysis reveals that the nanoscale l1_(2) precipitates contribute to the strength via the particle shearing mechanism,whereas the laves phase provides the strengthening through the Orowan bypass *** study of deformation microstruc-tures shows that the l1_(2) precipitates are sheared by stacking faults,which facilitates long-range disloca-tion gliding through the *** a result,deformation induces the formation of hierarchical stacking fault networks and immobile lomer-Cottrell locks,which effectively enhance the work hardening ca-pability and plastic stability,thereby resulting in a high ductility at high strength *** are piled-up against the interface between the laves precipitates and matrix,which increases the work hardening capability at the early stages of plastic deformation but causes stress *** dual precipitation strategy may be useful for many other alloys for achieving superior mechanical properties for technological applications.

关键词： High-entropy alloy Dual precipitation Precipitation strengthening Deformation mechanism

INtERNAl　OXIDAtION　KINEtICS　＆DIFFUSION　MECHANISM　OF　OXYGEN　IN　Cu－Al　SINtERED　AllOY

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Acta Metallurgica Sinica(English letters) 1996年第5期9卷 387-390页

作者： S.G. tian l.t. zhang H. M. Shao l.J. Zou t.F. li and H. C. Yang (Department of Materials Science, Shenyang Polytechnic University, Shenyang 110023, China) (Corrosion Science laboratory, Institute of Corrosion and Protection of Metals, Chinese Academy

In this paper, internal oxidation kinetics and the diffusion mechanism of oxygen in sintered Cu-Al alloy have been studied by means of scanning electron microscopy,transmission electron microscopy and heat-weighting scales. the results show that the kinetic curves obey the parabolic law in the initial stage and are linear in the late *** oxygen atoms are mainly transported in the from of grain boundary diffusion and volume diffusion in the process of internal oxidation. the plastic deformation of Cu matrix around oxide particles increases the probability of [O] atoms moving in accordance with dislocation diffusion mechanism. Meanwhile, the activation energy and diffusion coefficient in the process of internal oxidation are evaluated by means of kinetic method so as to obtain the velocity equations of reacting interface moving in different stage.

关键词： Cu-Al alloy internal oxidation diffusion

Plasma sheet stretching accompanied by field aligned energetic ion fluxes observed by the NUADU instrument aboard tC-2

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Chinese Science Bulletin 2007年第12期52卷 1719-1723页

作者： lU li S. MCKENNA-lAWlOR S. BARABASH lIU ZhenXing CAO JinBin J. BAlAZ K. KUDElA t. l. zhang C. M. CARR Centre for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China Space technology Ireland National University of Ireland Maynooth Co. Kildare Ireland Swedish Institute of Space Physics Kiruna Sweden Institute of Experimental Physics Kosice Slovakia Space Research Institute Austrian Academy of Sciences Graz Austria Imperial College of Science London United Kingdom

NUADU (中立原子察觉者单位) 在 tC-2 上的仪器记录了在 thenear 地球血浆表盘旋在磁场线附近的控告的粒子(E>180 keV ) 的 4nsolid 角度图象(在 ~-7 R_E，赤道的 dawn-to-night 方面) 在地磁气的暴风雨(Dst=-219 nt ) 期间在 2005 年 8... 详细信息

NUADU (中立原子察觉者单位) 在 tC-2 上的仪器记录了在 thenear 地球血浆表盘旋在磁场线附近的控告的粒子(E>180 keV ) 的 4nsolid 角度图象(在 ~-7 R_E，赤道的 dawn-to-night 方面) 在地磁气的暴风雨(Dst=-219 nt ) 期间在 2005 年 8 月 24 日。对称的、似环的、稳固的角度分布在周围的磁场线附近描绘的精力充沛的离子横梁事件被 thetC-2 太空船在血浆表的 34-minutetraversal 期间观察。另外，观察被磁强计实验(FGM ) 在一样的太空船上在血浆表的这些多重十字路口期间监视。在每个十字路口期间，口哨声模式合唱团改进被 tC-2 低频率电磁波察觉者(lFEW/tC-2 ) 就在本地更低的混血儿的上面在频率在各向异性的区域观察波浪。离子的比较与这块地里的改进排列了的周围的磁场表演搭角度分发(垫) 地图精力充沛的离子流动被尾巴病房在血浆表拉长磁场线伴随。相反，垂直离子流动改进被在血浆表显示磁场线的相应收缩的签名伴随。因为平行离子流动和垂直离子流动改进间歇地发生了，数据被解释暗示磁场线的一个动态、摆动的过程(拉长并且缩小)在thenear地球血浆表，它可能行动了帮助在将支持在进行中的磁性的暴风雨期间被触发的连续 aurora-substorm 的这个区域建立一个相互作用区域。thewhistler 模式合唱团可能在血浆表压缩以后在粒子沥青角度散开期间由于离子旋转罗盘回声被生产了。

关键词：近地等离子体片螺旋角分布离子流氖中立原子探测装置大气科学