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| 1 | Numerical study on ULF waves in a dipole field excited by sudden impulse显示文摘A three-dimensional numerical model is employed to investigate ULF waves ex-cited by the sudden impulse (SI) of the solar wind dynamic pressure interacting with a dipole magnetosphere. We focus on the solar wind-magnetosphere energy coupling through ULF waves, and the influences of the SI spectrum on the cavity mode structure and the energy deposition due to field line resonances (FLRs) in the magnetosphere. The numerical results show that for a given SI lasting for 1 min with amplitude of 50 mV/m impinging on the subsolar magnetopause, the total ULF energy transported from the solar wind to the magnetosphere is about the magni-tude of 1014 J. The efficiency of the solar wind energy input is around 1%, which depends little on the location of the magnetopause in the model. It is also found that the energy of the cavity mode is confined in the region near the magnetopause, whereas, the energy of the toroidal mode may be distributed among a few specific L-shells. With a given size of the model magnetosphere and plasma density distri-bution, it is shown that the fundamental eigenfrequency of the cavity mode and the central locations of the FLRs do not vary noticeably with the power spectrum of the SI. It is worth noting that the spectrum of the SI affects the excitation of higher harmonics of the global cavity mode. The broader the bandwidth of the SI is, the higher harmonics of cavity mode could be excited. Meanwhile, the corresponding FLRs regions are broadened at the same time, which implies that the global cavity modes and toroidal modes can resonate on more magnetic L-shells when more harmonics of the global cavity modes appear. | YANG Biao FU SuiYan ZONG QiuGang WANG YongFu ZHOU XuZhi PU ZuYin XIE Lun | 2008 | Science China(Technological Sciences)2008，51，10： | 12 |
| 2 | Multi-spacecraft observations of ULF waves during the recovery phase of magnetic storm on October 30, 2003显示文摘Based on observations obtained by Cluster C1, GOES 10, 12, and Polar, the global ULF wave properties are studied during the recovery phase of a very intense magnetic storm-Halloween storm (October 31, 2003, 21:00-23:00 UT). The results indicate that the ULF waves’ properties observed by different satellites, such as amplitude, period, etc. show large variations. This can be interpreted as that Field Line Resonance (FLR) might take place in the region where Cluster C1 passed. The compressional wave of the cavity mode coupled with FLR’s shear Alfven wave and fed energy to the latter, forming a large-amplitude toroidal mode. From the point of period, Cluster C1 observed the shortest period, GOES 10, 12 observed the middle, while Polar observed the longest. The wave period of toroidal mode observed by Cluster C1 kept almost unchanging when Cluster C1 passed L range from 11.7 to 5.3. Using the Squared Wavelet Coherence analysis method, we estimated that the FLR region in the dayside magnetosphere could expand to at least 4 local time widths. The toroidal mode observed by Polar was a standing wave, while the pol-oidal mode was a propagating wave, the observation results could be well ex-plained by the waveguide mode theory. Since the solarwind speed Vx was -800 km/s and the dynamic pressure varied little, we speculated that the source of the ULF wave was the Kelvin-Helmholtz instability at the magnetopause triggered by high speed solarwind. | YongFu Wang SuiYan Fu QiuGang Zong Biao Yang ZuYin Pu Lun Xie XuZhi Zhou | 2008 | Science China(Technological Sciences)2008，51，10： | 11 |
| 3 | Radial propagation of magnetospheric substorm-injected energetic electrons observed using a BD-IES instrument and Van Allen Probes显示文摘In cases where substorm injections can be observed simultaneously by multiple spacecraft,they can help elucidate the potential mechanisms of particle transport and energization,of great importance to understanding and modeling the magnetosphere.In this paper,using data returned from the BeiDa-IES(BD-IES) instrument onboard a satellite in an inclined(55°) geosynchronous orbit(IGSO),in combination with two geo-transfer orbiting(GTO) satellite Van Allen Probes(A and B),we analyze a substorm injection event that occurred on the 16 th of October 2015.During this substorm injection,the IGSO onboard BD-IES was outbound,while both Van Allen Probe satellites(A and B) were inbound,a configuration of multiple trajectories that provides a unique opportunity to simultaneously investigate both the inward and outward radial propagation of substorm injection.Indicated by AE/AL indices,this substorm was closely related to an IMF/solar wind discontinuity that showed a sharp change in IMF Bz direction to the north.The innermost signature of this substorm injection was detected by Van Allen Probes A and B at L-3.7,while the outermost signature was observed by the onboard BD-IES instrument at L~\0.These data indicate that the substorm had a global,rather than just local,effect.Finally,we suggest that electric fields carried by fast-mode compressional waves around the substorm injection are the most likely candidate mechanism for the electron injection signatures observed in the inner- and outermost inner magnetosphere. | ZONG QiuGang HAO YiXin ZOU Hong FU SuiYan ZHOU XuZhi REN Jie WANG LingHua YUAN ChongJing LIU ZhiYang JIA XiangHong QUAN Lin LIU Ying WANG YongFu | 2016 | Science China Earth Sciences2016，59，7： | 8 |
| 4 | miR-330-3p controls cell proliferation by targeting early growth response 2 in non-small-cell lung cancer显示文摘Non-small-cell 肺癌症(NSCLC ) 是最普通的肺癌症之一,并且 microRNAs (miRNAs ) 被报导了在 NSCLC 起必要作用。最近的研究显示了那 miR-330-3p 表情在 NSCLC 样品并且在 NSCLC 大脑转移的纸巾是起来调整的。在这研究, miR-330-3p 表示的起来规定在 NSCLC 和 20 件 NSCLC 耐心的样品被证实。而且, miR-330-3p 在 NSCLC 房间线 A549 和 H23 是过去表示的,并且 miR-330-3p 的提升功能在调整 NSCLC 房间增长和房间周期分发被调查。为了识别潜力,在 NSCLC 指向 miR-330-3p 的基因, miRNA 目标预言数据库被使用。酶活动试金和即时 RT-PCR 分析证实 miR-330-3p 否定地与早生长反应 2 的表示(EGR2 ) 被相关。而且, EGR2 mRNA 为 miR-330-3p 包含二个潜在的有约束力的地点,这也被发现。有 siRNA 的 EGR2 击倒被表明在 NSCLC 房间线作为 miR-330-3p 的在表示上有类似的效果。一起拿,我们的结果证明 EGR2 是 miR-330-3p 的一个目标。 | Xuzhi Liu Hanbing Shi Bo Liu Jianing Li Yaxin Liu Baiquan Yu | 2015 | Acta Biochimica et Biophysica Sinica2015，47，6： | 8 |
| 5 | Ultralow frequency wave characteristics extracted from particle data:Application of IGSO observations显示文摘3 Summary and discussion In the generalized drift resonance theory[17],a characteristic signature of the ULF wave-particle interactions is the increasingly-tilted stripes in the particle energy spectrum.The phase difference across different energy channels is relatively | LI Li ZHOU XuZhi ZONG QiuGang CHEN XingRan ZOU Hong REN Jie HAO YiXin ZHANG XianGuo | 2017 | Science China(Technological Sciences)2017，60，3： | 6 |
| 6 | Evaluation of joint toxicity of heavy metals and herbicide mixtures in soils to earthworms(Eisenia fetida)显示文摘It is widely acknowledged that a simplified and robust approach to evaluating thecombined effects of chemical mixtures is critical for ecological risk assessment(ERA)of contaminated soil.The earthworm(Eisenia fetida)was used as a model to study the combined effects of polymetallic contamination and the herbicide siduron in field soil using a microcosm experiment.The responses of multiple biomarkers,including the activities of catalase(CAT),superoxide dismutase(SOD),glutathione reductase(GR)and acetylcholine esterase(AChE),the concentrations of glycogen,soluble protein(SP),malonaldehyde(MDA),and metallothionein(MT),and the neutral red uptake test(NRU),were investigated.Multivariate analysis,Principal Component Analysis(PCA)and Spearman’s Rank Correlations analysis(BVSTEP)revealed that the activities of AChE and CAT and the NRU content were the prognostic biomarkers capturing the minimum data set of all the variables.Internal Cd(tissue Cd)in earthworms was closely related to the health status of worms under combined contamination of heavy metals and siduron.The integrated effect(E mix)calculated based on the activities of AChE and CAT and NRU content using the stress index method had significantly linear regression with internal Cd(p<0.01).E mix(10),E mix(20),and E mix(50)were then calculated,at 1.27,1.63 and 2.71 mg/kg dry weight,respectively.It could be concluded that a bioassaybased approach incorporating multivariate analysis and internal dose was pragmatic and applicable to evaluating combined effects of chemical mixtures in soils under the guidance of the top-down evaluation concept of combined toxicity. | Xuzhi Li Meie Wang Rong Jiang Liping Zheng Weiping Chen | 2020 | Journal of Environmental Sciences2020，32，8： | 6 |
| 7 | Imaging energetic electron spectrometer onboard a Chinese navigation satellite in the inclined GEO orbit显示文摘The energetic electron measurement is one of the most important issues to understand dynamics in space physics and the applications for space weather. In this study, the principle and functional components of the imaging energetic electron spectrometer(IES) onboard a Chinese navigation satellite in the inclined GEO orbit(IGSO) was introduced. The IES instrument is developed by the team in Peking University(BeiDa), thus it is named as BD-IES. Based on the pin-hole technique, the instrument can measure 50–600 keV electrons incident from 9 directions over a range of 180° in polar angle. With pulse height analysis(PHA), the spectrum can be determined for each direction. The energy and angular calibrations were performed, which show the good energy and angular characteristics of BD-IES. Monte Carlo simulations show that the anti-proton design of BDIES can effectively decrease the proton contamination on the electron measurements in the inclined GEO orbit. The primary results of BD-IES verify the successful design of this instrument. | ZOU Hong YE YuGuang ZONG QiuGang CHEN HongFei ZOU JiQing CHEN Jiang SHI WeiHong YU XiangQian ZHONG WeiYing WANG YongFu ZHOU XuZhi HAO YiXin CHEN XingRan JIA XiangHong XU Feng SHAO SiPei WANG Bo HAO XiaoYun ZHANG XiaoXin | 2018 | Science China(Technological Sciences)2018，61，12： | 5 |
| 8 | Roles of initial current carrier in the distribution of field-aligned current in 3-D Hall MHD simulations显示文摘A three-dimensional (3-D) Hall MHD simulation is carried out to study the roles of initial current carrier in the topology of magnetic field, the generation and distribu- tion of field aligned currents (FACs), and the appearance of Alfvén waves. Consid- ering the contribution of ions to the initial current, the topology of the obtained magnetic field turns to be more complex. In some cases, it is found that not only the traditional By quadrupole structure but also a reversal By quadrupole structure appears in the simulation box. This can explain the observational features near the diffusion region, which are inconsistent with the Hall MHD theory with the total ini- tial current carried by electrons. Several other interesting features are also emerged. First, motions of electrons and ions are decoupled from each other in the small plasma region (Hall effect region) with a scale less than or comparable with the ion inertial length or ion skin depth di=c/ωp. In the non-Hall effect region, the global magnetic structure is shifted in +y direction under the influence of ions with initial y directional motion. However, in the Hall effect region, magnetic field lines are bent in ?y direction, mainly controlled by the motion of electrons, then By is generated. Second, FACs emerge as a result of the appearance of By. Compared with the prior Hall MHD simulation results, the generated FACs shift in +y direction, and hence the dawn-dusk symmetry is broken. Third, the Walén relation in our simulations is consistent with the Walén relation in Hall plasma, thus the presence of Alfvén wave is confirmed. | ZHANG XianGuo PU ZuYin MA ZhiWei ZHOU XuZhi | 2008 | Science China(Technological Sciences)2008，51，3： | 4 |
| 9 | Magnetotail dipolarization fronts and particle acceleration:A review显示文摘In this paper, the particle acceleration processes around magnetotail dipolarization fronts(DFs) were reviewed. We summarize the spacecraft observations(including Cluster, THEMIS, MMS) and numerical simulations(including MHD, testparticle, hybrid, LSK, PIC) of these processes. Specifically, we(1) introduce the properties of DFs at MHD scale, ion scale, and electron scale,(2) review the properties of suprathermal electrons with particular focus on the pitch-angle distributions,(3)define the particle-acceleration process and distinguish it from the particle-heating process,(4) identify the particle-acceleration process from spacecraft measurements of energy fluxes, and(5) quantify the acceleration efficiency and compare it with other processes in the magnetosphere(e.g., magnetic reconnection and radiation-belt acceleration processes). We focus on both the acceleration of electrons and ions(including light ions and heavy ions). Regarding electron acceleration, we introduce Fermi,betatron, and non-adiabatic acceleration mechanisms;regarding ion acceleration, we present Fermi, betatron, reflection, resonance, and non-adiabatic acceleration mechanisms. We also discuss the unsolved problems and open questions relevant to this topic, and suggest directions for future studies. | Huishan FU Elena EGRIGORENKO Christine GABRIELSE Chengming LIU San LU KJHWANG Xuzhi ZHOU Zhe WANG Fang CHEN | 2020 | Science China Earth Sciences2020，63，2： | 4 |
| 10 | Monte Carlo simulations of the sensor head of imaging energetic electron spectrometer onboard a Chinese IGSO navigation satellite显示文摘An imaging energetic electron spectrometer built by the Peking University team(BD-IES) onboard a Chinese navigation satellite in an inclined GEO orbit has been launched successfully in September 2015, which measures the spectra of the energetic electrons with the energy range of 50–600 keV in nine directions. In this study, Monte Carlo simulations of the BD-IES sensor head were performed using Geant4 and the corresponding characteristic responses to the isotropic energetic particles were derived. The effective geometric factors were estimated using the typical electron and proton spectra in the GEO orbit and the corresponding simulated sensor head responses. It was found that the average effective geometric factors of nine directions are close to the nominal geometric factors calculated with the traditional method, but the effective geometric factor decreases as the center energy of the energy channel decreases. The BD-IES sensor head also responses to the energetic protons, but the average contamination rate of all 72 channels is about 2%, which means that the proton contamination is acceptable. The spectra of the energetic electrons measured by BD-IES are derived using the effective geometric factors of the sensor head and are comparable with the spectra measured by the magnetic electron ion spectrometer(MagEIS) instrument onboard Van Allen Probes. | ZOU Hong YE YuGuang ZONG QiuGang CHEN HongFei LUO Lin ZHOU XuZhi CHEN XingRan HAO YiXin REN Jie WANG YongFu SHI WeiHong YU XiangQian JIA XiangHong XU Feng ZHANG XiaoXin | 2019 | Science China(Technological Sciences)2019，62，7： | 3 |
| 11 | An implicit algorithm based on iterative modified approximate factorization method coupling with characteristic boundary conditions for solving subsonic viscous flows显示文摘An algorithm composed of an iterative modified approximate factorization(MAF(k)) method with Navier-Stokes characteristic boundary conditions(NSCBC) is proposed for solving subsonic viscous flows.A transformation on the matrix equation in MAF(k) is made in order to impose the implicit boundary conditions properly.To be in consistent with the implicit solver for the interior domain,an implicit scheme for NSCBC is formulated.The performance of the developed algorithm is investigated using spatially evolving zero pressure gradient boundary layer over a flat plate and a wall jet mixing with a cross flow over a flat plate with a square hole as the test cases.The numerical results are compared to the existing experimental datasets and a number of general correlations,together with other available numerical solutions,which demonstrate that the developed algorithm possesses promising capacity for simulating the subsonic viscous flows with large CFL number. | LEE XuZhi LEE ChunHian | 2013 | Science China(Physics,Mechanics & Astronomy)2013，56，6： | 2 |
| 12 | Test particle simulation on the ion and electron zebra stripes and their time evolution in inner radiation belt显示文摘During February 15–16, 2014, the energetic electron spectrogram for four successive inner radiation belt crossing show clearly the electron zebra structures and their time evolution which last for about 17 h. Unfortunately, the time of flight(TOF) in RBSPICE measurement is turned off below 3 RE, and the ion measurement is contaminated by electrons. Thus in this study we studied the differences between the ion and electron zebra stripe structures and their time evolution using simple theory and test particle simulation, combining the electron measurement from RBSIPICE onboard Van Allen Probes. Theoretical analysis predicts that the ion zebra stripe structures should lie at a higher energy range than the corresponding electron zebra stripe structures due to that the directions of gradient B drift and corotation E×B drift are the same for electrons while opposite for ions. Test particle simulation with the dipole magnetic field and Volland-Stern electric field model have shown that the ion and electron zebra stripe structures could be produced by the convection electric field penetrating into the inner magnetosphere in this event, with their time evolution determined by total drift velocity that are different for ions and electrons. The predicted differences between the ion and electron zebra stripe structures are partially verified through observation. The ion zebra stripe structures could have potential influence to the ring current. | WANG YongFu ZONG QiuGang ZHOU XuZhi | 2018 | Science China(Technological Sciences)2018，61，4： | 2 |
| 13 | Corotating drift-bounce resonance of plasmaspheric electron with poloidal ULF waves显示文摘The purpose of this paper is to understand how low energy plasmaspheric electrons respond to ULF waves excited by interplanetary shocks impinging on magnetosphere. It is found that both energy and pitch angle dispersed plasmaspheric electrons with energy of a few eV to tens of eV can be generated simultaneously by the interplanetary shock. The subsequent period of successive dispersion signatures is around 40 s and is consistent with the ULF wave period(third harmonic). By tracing back the energy and pitch angle dispersion signatures, the position of the electron injection region is found to be off-equator at around -32° in the southern hemisphere. This can be explained as the result of injected electrons being accelerated by higher harmonic ULF waves(e.g. third harmonic) which carry a larger amplitude electric field off-equator. The dispersion signatures are due to the flux modulations(or accelerations) of ' local' plasmaspheric electrons rather than electrons from the ionosphere. With the observed wave-borne large electric field excited by the interplanetary shock impact, the kinetic energy can increase to a maximum of 23 percent in one bouncing cycle for plasmaspheric electrons satisfying the drift-bounce resonance condition by taking account of both the corotating drift and bounce motion of the local plasmaspheric electron. | Qiu-Gang Zong YongFu Wang Jie Ren XuZhi Zhou SuiYan Fu Robert Rankin Hui Zhang | 2017 | Earth and Planetary Physics2017，1，1： | 2 |
| 14 | Design of DDR2 SDRAM Controller for Video Post Processing Pipeline显示文摘 | Xuzhi WANG Yanru MA Wanggen WAN | 2009 | Wireless Mobile and Computing2009，，： | 1 |
| 15 | 显示文摘 | MuRX XuZhY LILY etal | 2010 | J Hazard Mater2010，176，13： | 1 |
| 16 | SpacePbasedempiricalresearchonpublictransportcomplexnetworksin330citiesofChina显示文摘 | XUQing ZUZhenghu XUZhijing etal | 2013 | JournalofTransportationSystemsEngineeringandInformationTechnology2013，13，1： | 1 |
| 17 | UAV 2-D Track Smoothing Method Based on Non-uniform B-spline Interpolation显示文摘 | Hu Zhonghua Zhao Min Wang Xuzhi | 2011 | Journal of Aeronautics Astronautics and Aviation2011，43，： | 1 |
| 18 | Treatment effect of Bushen Huayu extract on postmenopausal osteoporosisin vivo显示文摘 | Lu Ouyang Qiufang Zhang Xuzhi Ruan Yibin Feng Xuanbin Wang | 2014 | Experimental and Therapeutic Medicine2014，，6： | 1 |
| 19 | UAV 2-D Track Smoothing Method Based on Non-uniform B-spline Interpolation显示文摘 | Hu Zhonghua Zhao Min Wang Xuzhi | 2011 | Journal of Aeronautics Astronautics and Aviation2011，43，2： | 1 |
| 20 | Fuzzy control strategy for the ac- robot显示文摘 | LAI Xuzhi CAI Zixing WU min et aI | 2000 | Kongzhi Lilun Yu Yinyong/Control Theory and Applications2000，17，3： | 1 |
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