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| 1 | Analysis of magnetotail flux rope events by ARTEMIS observations显示文摘Three earthward flowing magnetic flux ropes observed in the duskside plasma sheet at geocentric solar magnetospheric coordinate X~–55 Re by P1 and P2 of acceleration,reconnection,turbulence and electrodynamics of moon’s interaction with the sun mission during 13:00–15:00 UT on July 3,2012,were studied.The morphologies of the flux ropes were studied in detail based on Grad-Shfranov reconstruction method and electronic pitch angle distribution data.It is found that(1)the flux rope cross-sectional dimensions are 1.0 Re×0.78 Re,1.3 Re×0.78 Re,and 2.5 Re×1.25 Re,respectively.The magnetic field lines were asymmetric about the center with field line compression on both sides of the current sheet at the leading region;(2)the electron energy flux data presented asymmetry with larger electron flux and lower temperature in the precursor region.The flux ropes were blocked by the resistance of compressed particle density in the front central plasma sheet and the enhanced magnetic field on its sides;and(3)it is found that the flux rope has a layered structure.From inside out,event 1 can be divided into three regions,namely electronic depletion core region,closed field line region,and the caudal area possible with fields connected with the ionosphere.It suggests that the flux ropes cannot merge with the tail magnetic field lines near the lunar orbit.Especially,the flux rope asymmetrical shape reflects the different reconnection processes that caused it on both sides of the magnetic structure.The events shown in this paper support the multiple X-line magnetic reconnection model for flux ropes with in situ observations. | TIAN AnMin SHI QuanQi ZONG QiuGang DU Jian FU SuiYan DAI YaNan | 2014 | Science China(Technological Sciences)2014,57,5: | 5 |
| 2 | Braking of high-speed flows in the magnetotail:THEMIS joint observations显示文摘The motion and deceleration processes of plasma sheet high-speed flows have great significance to magnetospheric particle acceleration,magnetic field perturbation,magnetic flux transport,triggering of substorm,and the current system formation in the magnetotail.From February to April 2009,two satellites of the Time History of Events and Macroscale Interactions during Substorms mission,THA and THE,were often separated largely in Z direction,but had small X and Y separations.Such special configuration allows simultaneous observations of highspeed flows at the center and boundary of the plasma sheet.Based on selected case study and statistical analysis,it is found that for about 89%of the events we selected,the probe further away from the neutral sheet observed the high-speed flow earlier than the one close to the center,and the flow is mainly field aligned.And for about 95%events the probe further away from the neutral sheet observed higher X component of the plasma flow.With the hypothesis that parallel flow keeps the same speed during its earthward propagation while central plasma sheet stream uniformly or suddenly brakes on its way to the earth,we deduced the position where the deceleration begins to be between 13 Re and 17 Re downtail,where thenear-earth reconnection is supposed to occur.In addition,our statistical results show that dipolarization fronts observed in the central plasma sheet are more prominent than those observed in the plasma sheet boundary layer ahead of the high-speed flow. | Wensai Shang Zhonghua Yao Quanqi Shi Weijie Sun Suiyan Fu Jiang Liu Anmin Tian Qiugang Zong Zuyin Pu Ting Xiao Vassilis Angelopoulos | 2014 | Chinese Science Bulletin2014,59,3: | 3 |
| 3 | Shape and position of Earth's bow shock near-lunar orbit based on ARTEMIS data显示文摘Earth's bow shock is the result of interaction between the supersonic solar wind and Earth's magnetopause. However, data limitations mean the model of the shape and position of the bow shock are based largely on near-Earth satellite data. The model of the bow shock in the distant magnetotail and other factors that affect the bow shock, such as the interplanetary magnetic field(IMF) B_y, remain unclear. Here, based on the bow shock crossings of ARTEMIS from January 2011 to January 2015, new coefficients of the tail-flaring angle a of the Chao model(one of the most accurate models currently available) were obtained by fitting data from the middle-distance magnetotail(near-lunar orbit, geocentric distance -20R_E>X>-50R_E). In addition, the effects of the IMF B_y on the flaring angle a were analyzed. Our results showed that:(1) the new fitting coefficients of the Chao model in the middle-distance magnetotail are more consistent with the observed results;(2) the tail-flaring angle a of the bow shock increases as the absolute value of the IMF B_y increases. Moreover, positive IMF B_y has a greater effect than negative IMF B_y on flaring angle. These results provide a reference for bow shock modeling that includes the IMF B_y. | LIU Ji SHI QuanQi TIAN AnMin Lü JianYong WU Hao WANG Ming FU SuiYan YANG YuChen ZONG QiuGang ZHANG Jiang FENG YongYong PU ZuYin | 2016 | Science China Earth Sciences2016,59,8: | 3 |
| 4 | CExp: secure and verifiable outsourcing of composite modular exponentiation with single untrusted server显示文摘 | Shuai Li Longxia Huang Anmin Fu John Yearwood | 2017 | Digital Communications and Networks2017,3,4: | 2 |
| 5 | Propagation properties of foreshock cavitons: Cluster observations显示文摘Foreshock cavitons are transient phenomena observed in the terrestrial foreshock region.They are characterized by a simultaneous depression of magnetic field magnitude and plasma density,which are bounded with enhancements of these two parameters and surrounded by ultralow frequency(ULF)waves.Previous studies focused on the interplanetary magnetic field(IMF)conditions,solar wind(SW)conditions,and the growth of the foreshock waves related to the generation of foreshock cavitons.Previously,a multipoint spacecraft analysis method using Cluster data was applied to analyze only two foreshock cavitons,and this method did not consider uncertainties.In this study,multipoint spacecraft analysis methods,including the timing method,the minimum directional derivative(MDD)method,and the spatiotemporal difference(STD)method are applied to determine the velocity in both spacecraft and solar wind frames.The propagation properties show good agreement with previous results from simulations and observations that most cavitons move sunward in the solar wind frame,with the velocities larger than the Alfvén speed.The propagation properties of foreshock cavitons support the formation mechanism of cavitons in previous simulations,which suggested that cavitons are formed due to the nonlinear evolution of compressive ULF waves.We find that there is clear decreasing trend between the size of cavitons and their velocity in the solar wind frame.In addition,the timing method considering errors has been applied to study the evolution properties by comparing the velocities with errors of the leading and trailing edges,and we identify three stable cavitons and one contracting caviton,which has not been studied before.Most cavitons should remain stable when they travel toward the Earth’s bow shock.The relationship between the size of foreshock cavitons and their distance from the bow shock is also discussed. | WANG MengMeng YAO ShuTao SHI QuanQi ZHANG Hui TIAN AnMin DEGELING Alexander William ZHANG Shuai GUO RuiLong SUN WeiJie LIU Ji BAI ShiChen SHEN XiaoChen ZHU XiaoQiong FU SuiYan PU ZuYin | 2020 | Science China(Technological Sciences)2020,63,1: | 1 |
| 6 | Use of Visible and Near Infrared Spectroscopy to Predict Klason Lignin Content of Bamboo, Chinese Fir, Paulownia, and Poplar显示文摘 | Huang Anmin Li Gaiyun Fu Feng | 2008 | Wood Chemistry and Technology2008,28,: | 1 |
| 7 | Advance in the synthesis of aromatic amine via direct animation显示文摘Arylamines are very common and important organic molecules. Acting as important intermediates in medical and chemical industry, they are widely used in the synthesis of Pharmaceuticals, dyes, pesticides, rubber additives, isocyanates and heterocyclic compounds. The traditional methods for the synthesis of arylamines include several steps. The production of aniline, for example, includes the following steps: the production of nitro-benzene by the nitration of benzene, and the reduction of the | Tong Chen Changwei Hu Zhenjing Fu Anmin Tian | 2002 | Chinese Science Bulletin2002,47,23: | 1 |
| 8 | The semiannual variation of transpolar arc incidence and its relationship to the Russell–McPherron effect显示文摘Earth’s aurora is a luminescent phenomenon generated by the interaction between magnetospheric precipitating particles and the upper atmosphere;it plays an important role in magnetosphere–ionosphere(M-I)coupling.The transpolar arc(TPA)is a discrete auroral arc distributed in the noon-midnight direction poleward of the auroral oval and connects the dayside to the nightside sectors of the auroral oval.Studying the seasonal variation of TPA events can help us better understand the long-term variation of the interaction between the solar wind,the magnetosphere,and M-I coupling.However,a statistical study of the seasonal variation of TPA incidence has not previously been carried out.In this paper,we have identified 532 TPA events from the IMAGE database(2000–2005)and the Polar database(1996–2002),and calculated the incidence of TPA events for different months.We find a semiannual variation in TPA incidence.Clear peaks in the incidence of TPAs occur in March and September;a less pronounced peak appears in November.We also examine seasonal variation in the northward interplanetary magnetic field(IMF)over the same time period.The intensity and occurrence rate of the northward IMF exhibit patterns similar to that of the TPA incidence.Having studied IMF Bz before TPA onset,we find that strong and steady northward IMF conditions are favorable for TPA formation.We suggest that the semiannual variation observed in TPA incidence may be related to the Russell–McPherron(R-M)effect due to the projection effect of the IMF By under northward IMF conditions. | Tao Tang Jun Yang QuanQi Shi AnMin Tian Shi-Chen Bai Alexander William Degeling SuiYan Fu JingXian Liu Tong Shao ZeYuan Sun | 2020 | Earth and Planetary Physics2020,4,6: | 1 |
| 9 | Statistical properties of kinetic-scale magnetic holes in terrestrial space显示文摘Kinetic-scale magnetic holes(KSMHs)are structures characterized by a significant magnetic depression with a length scale on the order of the proton gyroradius.These 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 kineticscale.However,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 characteristics.In this study,KSMHs in near-Earth space are investigated statistically using data from the Magnetospheric Multiscale mission.Approximately 200,000 events were observed from September 2015 to March 2020.Occurrence rates of such structures in the solar wind,magnetosheath,and magnetotail were obtained.We find that KSMHs occur in the magnetosheath at rates far above their occurrence in the solar wind.This indicates that most of the structures are generated locally in the magnetosheath,rather than advected with the solar wind.Moreover,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 environment.Close to the magnetopause,we find that the depths of KSMHs decrease as their temporal-scale increases.We also find that the spatial-scales of the KSMHs near the subsolar magnetosheath are smaller than those in the flanks.Furthermore,their global distribution shows a significant dawn-dusk asymmetry(duskside dominating)in the magnetotail. | 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 | 2021 | Earth and Planetary Physics2021,5,1: | 1 |
| 10 | Rapid Estimation of Microfibril Angle of Increment Cores of Chinese Fir by Near Infrared Spectroscopy显示文摘Near infrared (NIR) spectroscope and X-ray diffractometry have been used for rapid prediction of the microfibril angle (MFA) which is one of the important factors affecting wood properties. Wood property evaluation in breeding and resource evaluation requires effective and rapid analysis methods for thousands of samples. In the experiment, all samples from increment cores with moisture content of 60% to 150% were used for measuring MFA by X-ray scanning diffractometry. Then, a partial least squares regression (PLS) model was built based on NIR data and MFA measured. As a result, a strong linear relationship was found between NIR spectroscope fitted and X-ray measured with coefficient of calibration 0.95 and prediction model rate 0.88. NIR estimating is in consist with X-ray determining closely, which indicates that NIR spectroscopy can be successfully used to estimate MFA of increment cores of Chinese fir. | HUANG Anmin FU Feng FEI Benhua JIANG Zehui Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, P. R. China | 2008 | Chinese Forestry Science and Technology2008,7,1: | 0 |