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| 1 | The effects of the guide field on the structures of electron density depletions in collisionless magnetic reconnection显示文摘Two-dimensional particle-in-cell simulations are performed to investigate the formation of electron density depletions in collisionless magnetic reconnection.In anti-parallel reconnection,the quadrupole structures of the out-of-plane magnetic field are formed,and four symmetric electron density depletion layers can be found along the separatrices due to the effects of magetic mirror.With the increase of the initial guide field,the symmetry of both the out-of-plane magnetic field and electron density depletion layers is distorted.When the initial guide field is sufficiently large,the electron density depletion layers along the lower left and upper right separatrices disappear.The parallel electric field in guide field reconnection is found to play an important role in forming such structures of the electron density depletion layers.The structures of the out-of-plane magnetic field By and electron depletion layers in anti-parallel and guide field reconnection are found to be related to electron flow or in-plane currents in the separatrix regions.In anti-parallel reconnection,electrons flow towards the X line along the separatrices,and are directed away from the X line along the magnetic field lines just inside the separatrices.In guide field reconnection,electrons can only flow towards the X line along the upper left and lower right separatrices due to the existence of the parallel electric field in these regions. | LU San LU QuanMing CAO Yang HUANG Can XIE JinLin WANG Shui | 2011 | Chinese Science Bulletin2011,56,1: | 8 |
| 2 | Electron dynamics in collisionless magnetic reconnection显示文摘Magnetic reconnection provides a physical mechanism for fast energy conversion from magnetic energy to plasma kinetic energy. It is closely associated with many explosive phenomena in space plasma, usually collisionless in character. For this reason, researchers have become more interested in collisionless magnetic reconnection. In this paper, the various roles of electron dynamics in collisionless magnetic reconnection are reviewed. First, at the ion inertial length scale, ions and electrons are decoupled. The resulting Hall effect determines the reconnection electric field. Moreover, electron motions determine the current system inside the reconnection plane and the electron density cavity along the separatrices. The current system in this plane produces an out-of-plane magnetic field. Second, at the electron inertial length scale, the anisotropy of electron pressure determines the magnitude of the reconnection electric field in this region. The production of energetic electrons, which is an important characteristic during magnetic reconnection, is accelerated by the reconnection electric field. In addition, the different topologies, temporal evolution and spatial distribution of the magnetic field affect the accelerating process of electrons and determine the final energy of the accelerated electrons. Third, we discuss results from simulations and spacecraft observations on the secondary magnetic islands produced due to secondary instabilities around the X point, and the associated energetic electrons. Furthermore, progress in laboratory plasma studies is also discussed in regard to electron dynamics during magnetic reconnection. Finally, some unresolved problems are presented. | LU QuanMing WANG RongSheng XIE JinLin HUANG Can LU San WANG Shui | 2011 | Chinese Science Bulletin2011,56,12: | 8 |
| 3 | Electron density hole and quadruple structure of B_y during collisionless magnetic reconnection显示文摘In collisionless reconnection,the magnetic field near the separatrix is stronger than that around the X-line,so an electron-beam can be formed and flows toward the X-line,which leads to a decrease of the electron density near the separatrix.Having been accelerated around the X-line,the electrons flow out along the magnetic field lines in the inner side of the separatrix.A quadruple structure of the Hall magnetic field By is formed by such a current system.A 2D particle-in-cell (PIC) simulation code is used in this paper to study the collisionless magnetic reconnection without an initial guide field.The current system described above is proved by the simulations.Furthermore,the position of the peak of the Hall magnetic field By is found to be between the separatrix and the center of the current sheet,which is verified by Cluster observations. | HUANG Can WANG RongSheng LU QuanMing WANG Shui | 2010 | Chinese Science Bulletin2010,55,8: | 4 |
| 4 | Construction of Cu-Ce interface for boosting toluene oxidation:Study of Cu-Ce interaction and intermediates identified by in situ DRIFTS显示文摘A facile hydrothermal method was applied to gain stably and highly efficient CuO-CeO_(2)(denoted as Cu1Ce2)catalyst for toluene oxidation.The changes of surface and inter properties on Cu1Ce2 were investigated comparing with pure CeO_(2)and pure CuO.The formation of Cu-Ce interface promotes the electron transfer between Cu and Ce through Cu^(2+)+Ce^(3+)↔Cu^(+)+Ce^(4+)and leads to high redox properties and mobility of oxygen species.Thus,the Cu1Ce2 catalyst makes up the shortcoming of CeO_(2)and CuO and achieved high catalytic performance with T_(50)=234°C and T_(99)=250°C(the temperature at which 50%and 90%C_(7)H_(8)conversion is obtained,respectively)for toluene oxidation.Different reaction steps and intermediates for toluene oxidation over Cu1Ce2,CeO_(2)and CuO were detected by in situ DRIFTS,the fast benzyl species conversion and preferential transformation of benzoates into carbonates through C=C breaking over Cu1Ce2 should accelerate the reaction. | Jiahui Lu Jinping Zhong Quanming Ren Jiaqi Li Linghe Song Shengpeng Mo Mingyuan Zhang Peirong Chen Mingli Fu Daiqi Ye | 2021 | Chinese Chemical Letters2021,32,11: | 2 |
| 5 | In situ evidence of resonant interactions between energetic electrons and whistler waves in magnetopause reconnection显示文摘In this paper,we analyze one reconnection event observed by the Magnetospheric Multiscale(MMS)mission at the earth’s magnetopause.In this event,the spacecraft crossed the reconnection current sheet from the magnetospheric side to the magnetosheath side,and whistler waves were observed on both the magnetospheric and magnetosheath sides.On the magnetospheric side,the whistler waves propagated quasi-parallel to the magnetic field and toward the X-line,while on the magnetosheath side they propagated almost anti-parallel to the magnetic field and away from the X-line.Associated with the enhancement of the whistler waves,we find that the fluxes of energetic electrons are concentrated around the pitch angle 90°when their energies are higher than the minimum energy that is necessary for the resonant interactions between the energetic electrons and whistler waves.This observation provides in situ observational evidence of resonant interactions between energetic electrons and whistler waves in the magnetic reconnection. | Zhi Li QuanMing Lu RongSheng Wang XinLiang Gao HuaYue Chen | 2019 | Earth and Planetary Physics2019,3,6: | 2 |
| 6 | Electron Acceleration in a Dynamically Evolved Current Sheet Under Solar Coronal Conditions显示文摘 | Shaohua Zhang A. M. Du Xueshang Feng Xin Cao Quanming Lu Liping Yang Gengxiong Chen Ying Zhang | 2014 | Solar Physics2014,,5: | 1 |
| 7 | Global hybrid simulations of soft X-ray emissions in the Earth’s magnetosheath显示文摘Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a satellite.By performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic field.In all cases,magnetic reconnection occurs at low latitude magnetopause.The soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the magnetosheath.Local X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray images.Moreover,the magnetopause boundary can be identified using multiple viewing geometries.We also find that solar wind conditions have little effect on the magnetopause identification.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered. | Jin Guo TianRan Sun San Lu QuanMing Lu Yu Lin XueYi Wang Chi Wang RongSheng Wang Kai Huang | 2024 | Earth and Planetary Physics2024,8,1: | 1 |
| 8 | Deformations at Earth’s dayside magnetopause during quasi-radial IMF conditions:Global kinetic simulations and Soft X-ray Imaging显示文摘The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)is a joint mission of the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS).Primary goals are investigating the dynamic response of the Earth's magnetosphere to the solar wind(SW)impact via simultaneous in situ magnetosheath plasma and magnetic field measurements,X-Ray images of the magnetosheath and magnetic cusps,and UV images of global auroral distributions.Magnetopause deformations associated with magnetosheath high speed jets(HSJs)under a quasi-parallel interplanetary magnetic field condition are studied using a threedimensional(3-D)global hybrid simulation.Soft X-ray intensity calculated based on both physical quantities of solar wind proton and oxygen ions is compared.We obtain key findings concerning deformations at the magnetopause:(1)Magnetopause deformations are highly coherent with the magnetosheath HSJs generated at the quasi-parallel region of the bow shock,(2)X-ray intensities estimated using solar wind h+and self-consistentO7+ions are consistent with each other,(3)Visual spacecraft are employed to check the discrimination ability for capturing magnetopause deformations on Lunar and polar orbits,respectively.The SMILE spacecraft on the polar orbit could be expected to provide opportunities for capturing the global geometry of the magnetopause in the equatorial plane.A striking point is that SMILE has the potential to capture small-scale magnetopause deformations and magnetosheath transients,such as HSJs,at medium altitudes on its orbit.Simulation results also demonstrate that a lunar based imager(e.g.,Lunar Environment heliospheric X-ray Imager,LEXI)is expected to observe a localized brightening of the magnetosheath during HSJ events in the meridian plane.These preliminary results might contribute to the pre-studies for the SMILE and LEXI missions by providing qualitative and quantitative soft X-ray estimates of dayside kinetic processes. | ZhongWei Yang RiKu Jarvinen XiaoCheng Guo TianRan Sun Dimitra Koutroumpa George K.Parks Can Huang BinBin Tang QuanMing Lu Chi Wang | 2024 | Earth and Planetary Physics2024,8,1: | 1 |
| 9 | A novel algorithm to determine minimum break point set for optimum cooperation of directional protection relays in multiloop networks 显示文摘 | Yue Quanming Lu Feipeng Yu Weiyong | 2006 | IEEE Transactions on Power Delivery2006,21,3: | 1 |
| 10 | A novel algorithm to determine minimum break point set for optimum cooperation of directional protection relays in multiloop networks显示文摘 | YUE Quanming LU Feipeng YU Weiyong | 2006 | IEEE Transactions on Power Delivery2006,21,3: | 1 |
| 11 | Electrostatic Structure of the Electron Phase-space Holes Generated by the Electron Two-stream Instability with a Finite Width显示文摘Space satellite observations in an electron phase-space hole(electron hole) have shown that bipolar structures are discovered at the parallel cut of parallel electric field, while unipolar structures spring from the parallel cut of perpendicular electric field. Particle-in-cell(PIC) simulations have demonstrated that the electron bi-stream instability induces several electron holes during its nonlinear evolution. However, how the unipolar structure of the parallel cut of the perpendicular electric field formed in these electron holes is still an unsolved problem,especially in a strongly magnetized plasma(Ω_e >ω_(pe), where Ω_e is defined as electron gyrofrequency and ω_(pe) is defined as plasma frequency, respectively). In this paper, with two-dimensional(2D) electrostatic PIC simulations, the evolution of the electron two-stream instability with a finite width in strongly magnetized plasma is investigated. Initially, those conditions lead to monochromatic electrostatic waves, and these waves coalesce with each other during their nonlinear evolution. At last, a solitary electrostatic structure is formed. In such an electron hole, a bipolar structure is formed in the parallel cut. of parallel electric field, while a unipolar structure presents in the parallel cut of perpendicular electric field. | SANG Longlong WU Mingyu LU Quanming | 2017 | 空间科学学报2017,37,5: | 1 |
| 12 | Ray-tracing simulations of whistler-mode wave propagation in different rescaled dipole magnetic fields显示文摘Kinetic simulation is a powerful tool to study the excitation and propagation of whistler-mode waves in the Earth’s inner magnetosphere.This method typically applies a scaled-down dipole magnetic field to save computational time.However,it remains unknown whether whistler wave propagation in the scaled-down dipole field is consistent with that in the realistic dipole field.In this work,we develop a ray-tracing code with a scalable dipole magnetic field to address this concern.The simulation results show that parallel whistler waves at different frequencies gradually become oblique after leaving the equator and propagate in different raypaths in a dipole magnetic field.During their propagation,the higher frequency waves tend to have larger wave normal angles at the same latitude.Compared with the wave propagation in a realistic dipole field,the wave raypath and wave normal remain the same,whereas the wave amplification or attenuation is smaller because of the shorter propagation time in a scaled-down dipole field.Our study provides significant guidance for kinetic simulations of whistler-mode waves. | YangGuang Ke QuanMing Lu XinLiang Gao HuaYue Chen Rui Chen | 2022 | Earth and Planetary Physics2022,6,6: | 0 |
| 13 | Simulation of mode conversion at the magnetopause显示文摘Two-dimensional(2-D)and three-dimensional(3-D)hybrid simulations are carried out for mode conversion from fast mode compressional wave to kinetic Alfvn waves(KAWs)at the inhomogeneous magnetopause boundary.For cases in which the incident fast wave propagates in the xz plane,with the magnetopause normal along x and the background magnetic field pointing along z,the 2-D (xz)simulation shows that KAWs with large wave number kxρi~1 are generated near the Alfve′n resonance surface,whereρi is the ion Larmor radius.Several nonlinear wave properties are manifest in the mode conversion process.Harmonics of the driver frequency are generated.As a result of nonlinear wave interaction,the mode conversion region and its spectral width are broadened.In the 3-D simulation,after this first stage of the mode conversion to KAWs with large kx,a subsequent generation of KAW modes of finite ky is observed in the later stage,through a nonlinear parametric decay process.Since the nonlinear cascade to ky can lead to massive transport at the magnetopause,the simulation results provide an effective transport mechanism at the plasma boundaries in space as well as laboratory plasmas. | LIN Yu JOHNSON Jay WANG XueYi LU QuanMing | 2012 | Chinese Science Bulletin2012,57,12: | 0 |
| 14 | Comparison between magnetic coplanarity and MVA methods in determining the normal of Venusian bow shock显示文摘With the measurements of magnetic field of Venus Express (VEX), magnetic coplanarity and minimum variance analysis (MVA) methods are analyzed and their validity is tested to determine the normal of Venusian bow shocks. It is found that MVA method is the better than magnetic coplanarity, and 95% shock crossings can be accurately determined by the method. However, the occurrence of the shock normal which is not determined accurately by magnetic coplanarity increases with the decrease of the solar zenith angle (SZA). At the same time, compared with quasi-parallel shocks, there is more occurrence of the shock normal which cannot be determined accurately by magnetic coplanarity for quasi-perpendicular shocks. | SHAN LiCan LU QuanMing ZHANG TieLong GAO XinLiang HUANG Can SU YanQing WANG Shui | 2013 | Chinese Science Bulletin2013,58,20: | 0 |
| 15 | Magnetic field annihilation and reconnection driven by femtosecond lasers in inhomogeneous plasma显示文摘The process of fast magnetic reconnection driven by intense ultra-short laser pulses in underdense plasma is investigated by particle-in-cell simulations. In the wakefield of such laser pulses, quasi-static magnetic fields at a few mega-Gauss are generated due to nonvanishing cross product ▽(n/) × p. Excited in an inhomogeneous plasma of decreasing density, the quasi-static magnetic field structure is shown to drift quickly both in lateral and longitudinal directions. When two parallel-propagating laser pulses with close focal spot separation are used, such field drifts can develop into magnetic reconnection(annihilation) in their overlapping region, resulting in the conversion of magnetic energy to kinetic energy of particles. The reconnection rate is found to be much higher than the value obtained in the Hall magnetic reconnection model. Our work proposes a potential way to study magnetic reconnection-related physics with short-pulse lasers of terawatt peak power only. | YouYuan Wang FeiYu Li Min Chen SuMing Weng QuanMing Lu QuanLi Dong ZhengMing Sheng Jie Zhang | 2017 | Science China(Physics,Mechanics & Astronomy)2017,60,11: | 0 |
| 16 | Study on electron stochastic motions in the magnetosonic wave field: Test particle simulations显示文摘Using the test particle simulation method, we investigate the stochastic motion of electrons with energy of 300 keV in a monochromatic magnetosonic(MS) wave field. This study is motivated by the violation of the quasi-linear theory assumption, when strong MS waves(amplitude up to ~1 nT) are present in the Earth's magnetosphere. First, electron motion can become stochastic when the wave amplitude exceeds a certain threshold. If an electron initially resonates with the MS wave via bounce resonance, as the bounce resonance order increases, the amplitude threshold of electron stochastic motion increases until it reaches the peak at about the 11 th order in our study, then the amplitude threshold slowly declines. Further, we find that the coexistence of bounce and Landau resonances between electrons and MS waves will significantly reduce the amplitude threshold. In some cases, the electron motion can become stochastic in the field of an MS wave with amplitudes below 1 nT. Regardless, if neither the bounce nor Landau resonance condition is satisfied initially, then the amplitude threshold of stochastic motion shows an increasing trend for lower frequencies and a decreasing trend for higher frequencies, even though the amplitude threshold is always very large(> 5 nT). Our study suggests that electron stochastic motion should also be considered when modeling electron dynamics regulated by intense MS waves in the Earth's magnetosphere. | Kai Fan XinLiang Gao QuanMing Lu Shui Wang | 2021 | Earth and Planetary Physics2021,5,6: | 0 |
| 17 | Two-stage acceleration of interstellar ions driven by high-energy lepton plasma flows显示文摘We present the particle-in-cell(PIC) simulation results of the interaction of a high-energy lepton plasma flow with background electron-proton plasma and focus on the acceleration processes of the protons. It is found that the acceleration follows a two-stage process. In the first stage, protons are significantly accelerated transversely(perpendicular to the lepton flow) by the turbulent magnetic field 'islands' generated via the strong Weibel-type instabilities. The accelerated protons shows a perfect inverse-power energy spectrum. As the interaction continues, a shockwave structure forms and the protons in front of the shockwave are reflected at twice of the shock speed, resulting in a quasi-monoenergetic peak located near 200 Me V under the simulation parameters. The presented scenario of ion acceleration may be relevant to cosmic-ray generation in some astrophysical environments. | CUI YunQian SHENG ZhengMing LU QuanMing LI YuTong ZHANG Jie | 2015 | Science China(Physics,Mechanics & Astronomy)2015,58,10: | 0 |
| 18 | Space physics and space weather显示文摘Space physics is a subject that has developed since the launch of the first artificial satellite in 1957. It has been promoted by space technology and is related closely with various adjacent disciplines. | LU QuanMing | 2011 | Chinese Science Bulletin2011,56,12: | 0 |
| 19 | Inhibition of aryl hydrocarbon receptor signaling promotes the terminal differentiation of human erythroblasts显示文摘The aryl hydrocarbon receptor(AHR)plays an important role during mammalian embryo development.Inhibition of AHR signaling promotes the development of hematopoietic stem/progenitor cells.AHR also regulates the functional maturation of blood cells,such as T cells and megakaryocytes.However,little is known about the role of AHR modulation during the development of erythroid cells.In this study,we used the AHR antagonist StemRegenin 1(SR1)and the AHR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin during different stages of human erythropoiesis to elucidate the function of AHR.We found that antagonizing AHR signaling improved the production of human embryonic stem cell derived erythrocytes and enhanced erythroid terminal differentiation.RNA sequencing showed that SR1 treatment of proerythroblasts upregulated the expression of erythrocyte differentiation-related genes and downregulated actin organization-associated genes.We found that SR1 accelerated F-actin remodeling in terminally differentiated erythrocytes,favoring their maturation of the cytoskeleton and enucleation.We demonstrated that the effects of AHR inhibition on erythroid maturation were associated with F-actin remodeling.Our findings help uncover the mechanism for AHRmediated human erythroid cell differentiation.We also provide a new approach toward the large-scale production of functionally mature human pluripotent stem cell-derived erythrocytes for use in translational applications. | Yijin Chen Yong Dong Xulin Lu Wanjing Li Yimeng Zhang Bin Mao Xu Pan Xiaohong Li Ya Zhou Quanming An Fangxin Xie Shihui Wang Yuan Xue Xinping Cai Mowen Lai Qiongxiu Zhou Yan Yan Ruohan Fu Hong Wang Tatsutoshi Nakahata Xiuli An Lihong Shi Yonggang Zhang Feng Ma | 2022 | Journal of Molecular Cell Biology2022,14,2: | 0 |
| 20 | Effect of Ion Dynamics on the Evolution of Electron Phase-space Holes显示文摘The evolution of two-dimensional(2D) electron phase-space holes(electron holes) has been previously investigated with electrostatic Particle-in-Cell(PIC) simulations,which neglect ion dynamics.The electron holes are found to be unstable to the transverse instability,and their evolution is determined by the combined action between the transverse instability and the stabilization by the background magnetic field.In this paper,the effect of ion dynamics on the evolution of an electron hole is studied.In weakly magnetized plasma(Ωe<ωpe,whereΩe andωpe are electron gyrofrequency and plasma frequency,respectively),the electron hole is still unstable to the transverse instability. However,it evolves a little faster and is destroyed in a shorter time when ion dynamics is considered. In strongly magnetized plasma(Ωe>ωpe),the electron hole is broken due to the lower hybrid waves, and its evolution is much faster. | WANG Peiran LU Quanming WU Mingyu WANG Shui | 2013 | 空间科学学报2013,33,4: | 0 |