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Earth and Planetary Physics 2018年第3期2卷 231-237页

作者： qiu-gang zong Hui Zhang Institute of Space Physics and Applied Technology Peking University Geophysical Institute University of Alaska Fairbanks

Magnetic reconnection is the most fundamental energy-transfer mechanism in the universe that converts magnetic energy into heat and kinetic energy of charged *** reconnection to occur,the frozen-in condition must break down in a localized region,commonly called the ‘diffusion region'.In Earth's magnetosphere,ion diffusion regions have already been observed,while electron diffusion regions have not been detected due to their small scales(of the order of a few km)(Paschmann,2008).In this paper we report,for the first time,in situ observations of an active electron diffusion region by the four Cluster spacecraft at the Earth's highlatitude *** electron diffusion region is characterized by nongyrotropic electron distribution,strong field-aligned currents carried by electrons and bi-directional super-Alfvénic electron *** observed were multiple micro-scale flux ropes,with a scale size of about 5 c/ω_(pe)(12 km,with c/ωpe the electron inertial length),that are crucial for electron acceleration in the guide-field reconnection process(Drake et al.,2006 a).The data demonstrate the existence of the electron diffusion region in collisionless guide-field reconnection at the magnetopause.

关键词： electron diffusion region magnetic reconnection high-latitude magnetopause

Dynamics of the inner electron radiation belt:A review

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Earth and Planetary Physics 2023年第1期7卷 109-118页

作者： YuXuan Li Chao Yue Ying Liu qiu-gang zong Hong Zou YuGuang Ye Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China

The Van Allen radiation belts are an extraordinary science discovery in the Earth magnetosphere and consist of two electron *** inner Van Allen belt contains electrons of 10s to 100s keV;the outer belt consists mainly of 0.1-10 MeV *** dynamics have been analyzed for *** newly-launched Van Allen Probes provide unprecedented opportunities to investigate the inner belt more *** from this advanced mission have allowed scientists to demonstrate that the inner belt was formed not only through inward transport of outer belt electrons but Cosmic Ray Albedo Neutron Decay(CRAND)has also played an important *** addition,the inner belt electrons show energy-dependent variations and present“zebra stripe”structures in the energy *** the same time,scientists have further confirmed that the electrons in the inner radiation belt get lost through coulomb collision and wave-particle *** these advances,important questions remain unanswered and require further *** launch of Macao Science Satellite-1 mission,with its low inclination angle and low altitude orbit,will provide advanced radiation belt data for better understanding of the structure and dynamics of the inner electron radiation belt.

关键词： Macao Scientific Satellite-1 mission zebra stripes inward transport CRAND coulomb collision wave-particle interaction

Corotating drift-bounce resonance of plasmaspheric electron with poloidal ULF waves

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Earth and Planetary Physics 2017年第1期1卷 2-12页

作者： qiu-gang zong YongFu Wang Jie Ren XuZhi Zhou SuiYan Fu Robert Rankin Hui Zhang Institute of Space Physics and Applied Technology Peking University Department of Physics University of Alberta Physics Department and Geophysical Institute University of Alaska Fairbanks

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.

关键词： drift-bounce resonance plasmaspheric electron poloidal mode ULF wave

Spatiotemporal Behavior of ULF waves excited by interplanetary shock and solar wind dynamic pressure impulses in the magnetosphere

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Spatiotemporal Behavior of ULF waves excited by interplaneta...

Introduction to special section on the China Seismo-Electromagnetic Satellite and initial results

2014年中国地球科学联合学术年会——专题29：空间天气与人类活动

作者： qiu-gang zong Peking University

When an interplanetary shock or a solar wind dynamic pressure impulse impinges on the magnetophere,ultra low-frequency(ULF)waves can be excited in the magnetosphere and the solar wind energy can be transported from interplanetary space into the inner *** this study,we have systematically studied ULF waves excited at in the magnetosphere by interplanetary shock or solar wind dynamic pressure *** have found that the poloidal and toroidal waves excited by positive and negative pressure pulses oscillate in a similar manner of phase near 06:00 local time(MLT)and

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来源： cnki会议评论

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Earth and Planetary Physics 2018年第6期2卷 439-443页

作者： XuHui Shen qiu-gang zong XueMin Zhang Institute of Crustal Dynamics China Earthquake Administration School of Earth and Space Science Peking University Institute of Earthquake Forecasting China Earthquake Administration

*** The China Seismo-Electromagnetic Satellite (CSES), which is also called ZhangHeng-1 (ZH-1), is the first Chinese space-borne platform dedicated to geophysical field measurement andearthquake monitoring by detecting variations in the electromagnetic environment of space. The CSES was launched successfully at15:51 on February 2, 2018, at China’s Jiuquan Satellite Launching Center.

关键词： CSES satellite scientific payload data product scientific application

Energetic electron detection packages on board Chinese navigation satellites in MEO

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Earth and Planetary Physics 2021年第2期5卷 158-179页

作者： YuGuang Ye Hong Zou qiu-gang zong HongFei Chen JiQing Zou WeiHong Shi XiangQian Yu WeiYing Zhong YongFu Wang YiXin Hao ZhiYang Liu XiangHong Jia Bo Wang XiaoPing Yang XiaoYun Hao School of Earth and Space Sciences Peking UniversityBeijing 100871China State Key Laboratory of Space Medicine Fundamentals and Application Chinese Astronaut Research and Training CenterBeijing 100093China Shandong Aerospace Electro-technology Yantai Shandong 264000China

Energetic electron measurements and spacecraft charging are of great significance for theoretical research in space physics and space weather *** this paper,the energetic electron detection package(EEDP)deployed on three Chinese navigation satellites in medium Earth orbit(MEO)is *** instrument was developed by the space science payload team led by Peking *** EEDP includes a pinhole medium-energy electron spectrometer(MES),a high-energy electron detector(HED)based onΔE-E telescope technology,and a deep dielectric charging monitor(DDCM).The MES measures the energy spectra of 50−600 keV electrons from nine directions with a 180°×30°field of view(FOV).The HED measures the energy spectrum of 0.5−3.0 MeV electrons from one direction with a 30°cone-angle *** ground test and calibration results indicate that these three sensors exhibit excellent *** observations show that the electron spectra measured by the MES and HED are in good agreement with the results from the magnetic electron-ion spectrometer(MagEIS)of the Van Allen Probes spacecraft,with an average relative deviation of 27.3%for the energy *** charging currents and voltages measured by the DDCM during storms are consistent with the highenergy electron observations of the HED,demonstrating the effectiveness of the *** observations of the EEDP on board the three MEO satellites can provide important support for theoretical research on the radiation belts and the applications related to space weather.

关键词： radiation belts energetic electron detection Pin-hole technology Chinese navigation satellites MEO internal charging

Poleward-moving recurrent auroral arcs associated with impulse-excited standing hydromagnetic waves

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Earth and Planetary Physics 2019年第4期3卷 305-313页

作者： HuaYu Zhao Xu-Zhi Zhou Ying Liu qiu-gang zong Robert Rankin YongFu Wang QuanQi Shi Xiao-Chen Shen Jie Ren Han Liu XingRan Chen School of Earth and Space Sciences Peking University Beijing 100871 China Department of Physics University of Alberta Edmonton Alberta T6G2J1 Canada School of Space Science and Physics Shandong University Weihai 264209 China Center for Space Physics Boston University Boston Massachusetts 02215 USA

In Earth's high-latitude ionosphere, the poleward motion of east–west elongated auroral arcs has been attributed to standing hydromagnetic waves, especially when the auroral arcs appear quasi-periodically with a recurrence time of a few minutes. The validation of this scenario requires spacecraft observations of ultra-low-frequency hydromagnetic waves in the magnetosphere and simultaneous observations of poleward-moving auroral arcs near the spacecraft footprints. Here we present the first observational evidence from the multi-spacecraft THEMIS (Time History of Events and Macroscale Interactions during Substorms) mission and the conjugated all-sky imager to support the scenario that standing hydromagnetic waves can generate the quasi-periodic appearance of poleward-moving auroral arcs. In this specific event, the observed waves were toroidal branches of the standing hydromagnetic waves, which were excited by a pulse in the solar wind dynamic pressure. Multi-spacecraft measurements from THEMIS also suggest higher wave frequencies at lower L shells (consistent with the distribution of magnetic field line eigenfrequencies), which indicates that the phase difference across latitudes would increase with time. As time proceeds, the enlarged phase difference corresponds to a lower propagation speed of the auroral arcs, which agrees very well with the ground-based optical data.

关键词： poleward-moving auroral arcs ULF waves standing hydromagnetic waves field-aligned currents solar wind dynamic pressure pulse

Statistical properties of kinetic-scale magnetic holes in terrestrial space

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Earth and Planetary Physics 2021年第1期5卷 63-72页

作者： ShuTao Yao zongShun Yue QuanQi Shi Alexander William Degeling HuiShan Fu AnMin Tian Hui Zhang Andrew Vu RuiLong Guo ZhongHua Yao Ji Liu qiu-gang zong XuZhi Zhou JingHuan Li WenYa Li HongQiao Hu YangYang Liu WeiJie Sun Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai Shandong 264209China State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China School of Space and Environment Beihang UniversityBeijing 100191China Physics Department and Geophysical Institute University of Alaska FairbanksFairbanksAK99775USA Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Laboratoire de Physique Atmosphérique et Planétaire STAR InstituteUniversitéde LiègeLiègeB-4000Belgium School of Earth and Space Sciences Peking UniversityBeijing 100871China SOA Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China Department of Climate and Space Sciences and Engineering University of MichiganAnn ArborMI48109USA

Kinetic-scale magnetic holes(KSMHs)are structures characterized by a significant magnetic depression with a length scale on the order of the proton *** structures have been investigated in recent studies in near-Earth space,and found to be closely related to energy conversion and particle acceleration,wave-particle interactions,magnetic reconnection,and turbulence at the ***,there are still several major issues of the KSMHs that need further study—including(a)the source of these structures(locally generated in near-Earth space,or carried by the solar wind),(b)the environmental conditions leading to their generation,and(c)their spatio-temporal *** this study,KSMHs in near-Earth space are investigated statistically using data from the Magnetospheric Multiscale *** 200,000 events were observed from September 2015 to March *** rates of such structures in the solar wind,magnetosheath,and magnetotail were *** find that KSMHs occur in the magnetosheath at rates far above their occurrence in the solar *** indicates that most of the structures are generated locally in the magnetosheath,rather than advected with the solar ***,KSMHs occur in the downstream region of the quasi-parallel shock at rates significantly higher than in the downstream region of the quasi-perpendicular shock,indicating a relationship with the turbulent plasma *** to the magnetopause,we find that the depths of KSMHs decrease as their temporal-scale *** also find that the spatial-scales of the KSMHs near the subsolar magnetosheath are smaller than those in the ***,their global distribution shows a significant dawn-dusk asymmetry(duskside dominating)in the magnetotail.

关键词： kinetic scale magnetic hole magnetic dip electron vortex turbulence

An approximate analytical model for unconventional reservoir considering variable matrix blocks and simultaneous matrix depletion

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Petroleum Science 2024年第1期21卷 352-365页

作者： Kai-Xuan qiu Jia Li Dong Feng Shi-Ming Wei gang Lei Jiangmen Laboratory of Carbon Science and Technology Jiangmen529100GuangdongChina The Hong Kong University of Science and Technology(Guangzhou) Guangzhou511400GuangdongChina China University of Geosciences(Beijing) Beijing100083China China University of Petroleum(Beijing) Beijing102249China China University of Geosciences(Wuhan) Wuhan430074HubeiChina Shenzhen Research Institute China University of GeosciencesShenzhen518063GuangdongChina

In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture *** has been proven to cause inaccurate production evaluations because of the absence of matrix-macrofracture *** addition,most of the existing models are solved analytically based on Laplace transform and numerical ***,an approximate analytical solution is derived directly in real-time space considering variable matrix blocks and simultaneous matrix *** simplify the derivation,the simultaneous matrix depletion is divided into two parts:one part feeding the macrofractures and the other part feeding the ***,a series of partial differential equations(PDEs)describing the transient flow and boundary conditions are constructed and solved analytically by ***,a relationship between oil rate and production time in real-time space is *** new model is verified against classical analytical *** the microfracture system and matrix-macrofracture communication is neglected,the result of the new model agrees with those obtained with the dual-porosity and triple-porosity model,***,the new model also has an excellent agreement with the numerical *** model is then applied to two actual tight oil wells completed in western Canada sedimentary *** identifying the flow regime,the solution suitably matches the field production data,and the model parameters are *** these output parameters,we can accurately forecast the production and even estimate the petrophysical properties.

关键词： Analytical solution Unconventional reservoir Variable matrix Simultaneous flow

Microstructure Evolution,Tribological and Corrosion Properties of Amorphous Alloy Strengthening Stainless Steel Fabricated by Selective Laser Melting in NaCl Solution

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 825-839页

作者： Pengwei Jiang gang Wang Yaosha Wu Zhigang Zheng Zhaoguo qiu Tongchun Kuang Jibo Huang Dechang Zeng School of Materials Science and Engineering South China University of TechnologyGuangzhou 510640China Zhongshan R&D Center for Materials Surface and Thin Films Technology of the South China University of Technology Gent Materials Surface Technology(Guangdong)Co.Ltd.Zhongshan 528437China Zhongshan Torch Polytechnic Zhongshan 528436China Yangjiang Branch Guangdong Laboratory Materials Science and Technology Yangjiang Advanced Alloys LaboratoryYangjiang 529599China

As a type of austenitic stainless steel,316L stainless steel has excellent plasticity,corrosion resistance,and biocompatibility,making it widely used in industries,especially in the marine ***,its lower yield strength and wear resistance are the obvious disadvantages that restrict its application in more *** this work,an Fe-based amorphous alloy(Fe^(am))was selected as reinforcement to enhance the 316L stainless steel prepared by selective laser melting(SLM),and microstructure evolution,mechanical properties,tribological and corrosion performance of the SLMed samples were investigated in *** relative density values of both 316L stainless steel and Fe^(am)-reinforced samples are above 99%,which suggests that Fe^(am)-reinforced samples also have outstanding *** the as-etched micrograph,all of the SLMed samples exhibit cellular ***^(am)-reinforced samples have thicker sub-grain boundaries,and retained amorphous phase can be observed in the samples reinforced with 10 wt%and 15 wt%Fe^(am).As the addition of Fe^(am) increases,the microhardness and compression strength of the Fe^(am)-reinforced samples gradually improve and reach 449.2 HV and 2181.9 MPa,*** wear morphologies show that the 316L stainless steel and Fe^(am)-reinforced samples both experience abrasive wear and corrosion wear in a 3.5 wt%NaCl ***,as the amount of Fe^(am) added increases,the coefficient of friction and wear rate of SLMed samples gradually *** to the unreinforced sample,Fe^(am)-reinforced samples have lower corrosion current density and higher pitting potential according to the potentiodynamic polarization curves and also exhibit superior corrosion resistance in the salt spray *** work suggests that the addition of Fe-based amorphous alloy can improve the mechanical properties and wear resistance of 316L stainless steel,as well as its ability to withstand salt spray corrosion.

关键词： Selective laser melting 316L stainless steel Amorphous alloy Tribology Corrosion