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Origin and structures of solar eruptions Ⅰ: Magnetic flux rope

Science China Earth Sciences 2017年第8期60卷 1383-1407页

作者： CHENG Xin GUO Yang ding mingde School of Astronomy and Space Science Nanjing University Key Laboratory for Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education

Coronal mass ejections(CMEs) and solar flares are the large-scale and most energetic eruptive phenomena in our solar system and able to release a large quantity of plasma and magnetic flux from the solar atmosphere into the solar wind. When these high-speed magnetized plasmas along with the energetic particles arrive at the Earth, they may interact with the magnetosphere and ionosphere, and seriously affect the safety of human high-tech activities in outer space. The travel time of a CME to 1 AU is about 1–3 days, while energetic particles from the eruptions arrive even earlier. An efficient forecast of these phenomena therefore requires a clear detection of CMEs/flares at the stage as early as possible. To estimate the possibility of an eruption leading to a CME/flare, we need to elucidate some fundamental but elusive processes including in particular the origin and structures of CMEs/flares. Understanding these processes can not only improve the prediction of the occurrence of CMEs/flares and their effects on geospace and the heliosphere but also help understand the mass ejections and flares on other solar-type stars. The main purpose of this review is to address the origin and early structures of CMEs/flares, from multi-wavelength observational perspective. First of all, we start with the ongoing debate of whether the pre-eruptive configuration, i.e., a helical magnetic flux rope(MFR), of CMEs/flares exists before the eruption and then emphatically introduce observational manifestations of the MFR. Secondly, we elaborate on the possible formation mechanisms of the MFR through distinct ways. Thirdly, we discuss the initiation of the MFR and associated dynamics during its evolution toward the CME/flare. Finally, we come to some conclusions and put forward some prospects in the future.

关键词： Coronal mass ejections Flares Magnetic flux ropes Magnetic field EUV/UV emissions Photosphere Corona Particle acceleration

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Origin and structures of solar eruptions Ⅱ: Magnetic modeling

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Science China Earth Sciences 2017年第8期60卷 1408-1439页

作者： GUO Yang CHENG Xin ding mingde School of Astronomy and Space Science Nanjing University Key Laboratory for Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education

The topology and dynamics of the three-dimensional magnetic field in the solar atmosphere govern various solar eruptive phenomena and activities, such as flares, coronal mass ejections, and filaments/prominences. We have to observe and model the vector magnetic field to understand the structures and physical mechanisms of these solar activities. Vector magnetic fields on the photosphere are routinely observed via the polarized light, and inferred with the inversion of Stokes profiles. To analyze these vector magnetic fields, we need first to remove the 180° ambiguity of the transverse components and correct the projection effect. Then, the vector magnetic field can be served as the boundary conditions for a force-free field modeling after a proper preprocessing. The photospheric velocity field can also be derived from a time sequence of vector magnetic ***-dimensional magnetic field could be derived and studied with theoretical force-free field models, numerical nonlinear force-free field models, magnetohydrostatic models, and magnetohydrodynamic models. Magnetic energy can be computed with three-dimensional magnetic field models or a time series of vector magnetic field. The magnetic topology is analyzed by pinpointing the positions of magnetic null points, bald patches, and quasi-separatrix layers. As a well conserved physical quantity,magnetic helicity can be computed with various methods, such as the finite volume method, discrete flux tube method, and helicity flux integration method. This quantity serves as a promising parameter characterizing the activity level of solar active regions.

关键词： Solar activity Solar corona Coronal Mass Ejections(CMEs) Solar flares Magnetic fields Solar photosphere

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日地L5太阳探测工程概述

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上海航天（中英文） 2024年第3期41卷 9-16页

作者：方成丁明德陈鹏飞李川程鑫郭洋戴煜李臻南京大学天文与空间科学学院江苏南京210023

南京大学联合中国气象局、上海航天技术研究院等单位共同建议的日地L5太阳探测工程——“羲和二号”,将在国际上首次发射一颗人造探测器至日地系统第5个拉格朗日点,通过精测矢量磁场、揭示三维爆发和精准预警预报,解答“活动区磁场的产... 详细信息

南京大学联合中国气象局、上海航天技术研究院等单位共同建议的日地L5太阳探测工程——“羲和二号”,将在国际上首次发射一颗人造探测器至日地系统第5个拉格朗日点,通过精测矢量磁场、揭示三维爆发和精准预警预报,解答“活动区磁场的产生演化及其与太阳爆发的物理联系”和“太阳爆发的传播规律及其与灾害性空间天气的关系”这2个太阳物理和空间天气领域亟待解决的重大科学和应用问题。本文重点阐述“羲和二号”的科学与应用目标,简要介绍其科学载荷和初步方案。联合日地连线方向上的太阳探测,“羲和二号”的实施将开启我国太阳立体探测时代,拓展人类对太阳爆发机制的理解,为空间天气预警预报带来革命性突破。

关键词：太阳活动太阳磁场太阳耀斑日冕物质抛射日地关系

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腹腔镜下自体筋膜修复术治疗DeLanceyⅠ和Ⅱ水平盆腔脏器脱垂的近期效果

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河北医药 2024年第16期46卷 2491-2494页

作者：刘西鹏丁明德张辉张毅芳李瑞雪张维福刘光海山东第一医科大学第二附属医院妇科山东省泰安市271000 山东第一医科大学第二附属医院公共卫生科山东省泰安市271000

目的评估改良腹腔镜下自体筋膜修复术治疗DeLancey I和Ⅱ水平盆腔脏器脱垂的有效性和安全性。方法选取2020年5月至2021年5月因DeLancey I和Ⅱ水平盆腔器官脱垂接受腹腔镜下自体筋膜修复术病例共15例,根据女性盆腔“整体理论”,利用自体... 详细信息

目的评估改良腹腔镜下自体筋膜修复术治疗DeLancey I和Ⅱ水平盆腔脏器脱垂的有效性和安全性。方法选取2020年5月至2021年5月因DeLancey I和Ⅱ水平盆腔器官脱垂接受腹腔镜下自体筋膜修复术病例共15例,根据女性盆腔“整体理论”,利用自体筋膜的修复重建达到解剖、功能复位,并根据盆腔脏器脱垂量化分度(POP-Q)分度法和患者的主观感受来评价手术效果。结果手术时间平均(136.18±7.73)min,术中出血平均(52.14±22.59)mL,均无术中输血,术后住院时间平均(5.07±0.62)d,术后随访时间平均(9.36±2.15)个月,主观满意度为86.67%(13/15)。15例患者中,1例患者在术后4个月提重物(约10 kg)时导致子宫脱垂复发,余14例患者与术前相比,DeLancey I和Ⅱ水平所有指示点在术后1年内的位置变化均存在统计学意义(P<0.05)。压力性尿失禁、腰骶部下坠不适、腰酸等症状明显改善。15例患者盆底障碍影响简易问卷(PFIQ-7)评分、盆底不适调查表简表(PFDI-20)评分均较术前下降,差异有统计学意义(P<0.05)。结论此次设计的手术主要针对DeLancey I和Ⅱ水平盆腔脏器脱垂的患者,手术的近期疗效稳定,安全性好,无并发症发生,远期疗效有待进一步观察。

关键词：盆腔器官脱垂腹腔镜自体筋膜修复宫骶韧带重建耻骨宫颈筋膜

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Evolution of the Toroidal Flux of CME Flux Ropes during Eruption

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The Innovation 2020年第3期1卷 37-43页

作者： Chen Xing Xin Cheng mingde ding School of Astronomy and Space Science Nanjing UniversityNanjing 210046China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China

Coronal mass ejections(CMEs)are large-scale explosions of the coronal magnetic *** is believed that magnetic reconnection significantly builds up the core structure of CMEs,a magnetic flux rope,during the ***,the quantitative evolution of the flux rope,particularly its toroidal flux,is still *** this paper,we study the evolution of the toroidal flux of the CME flux rope for four *** toroidal flux is estimated as the magnetic flux in the footpoint region of the flux rope,which is identified by a method that simultaneously takes the coronal dimming and the hook of the flare ribbon into *** find that the toroidal flux of the CME flux rope for all four events shows a two-phase evolution:a rapid increasing phase followed by a decreasing *** further compare the evolution of the toroidal flux with that of the Geostationary Operational Environmental Satellites soft X-ray flux and find that they are basically synchronous in time,except that the peak of the former is somewhat *** results suggest that the toroidal flux of the CME flux rope may be first quickly built up by the reconnection mainly taking place in the sheared overlying field and then reduced by the reconnection among the twisted field lines within the flux rope,as enlightened by a recent 3D magnetohydrodynamic simulation of CMEs.

关键词： SUN:CORONA SUN:CORONAL MASS EJECTIONS(CMES) SUN:FLARES

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Probing the Production of Extreme-ultraviolet Late-Phase Solar Flares by Using the Model Enthalpy-Based Thermal Evolution of Loops

Probing the Production of Extreme-ultraviolet Late-Phase Sol...

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第35届中国气象学会年会

作者： Yu Dai mingde ding School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of Education Key Laboratory of Space Weather National Center for Space Weather China Meteorological Administration

Recent observations in extreme-ultraviolet(EUV) wavelengths reveal an EUV late phase in some solar flares that is characterized by a second peak in warm coronal emissions(3 MK) several tens of minutes to a few hours after the soft X-ray(SXR) peak. Using the model enthalpy-based thermal evolution of loops(EBTEL), in this paper we numerically probe the production of EUV late-phase solar flares. Starting from two main mechanisms of producing the EUV late phase, i.e., long-lasting cooling and secondary heating, we carry out two groups of numerical experiments to study the effects of these two processes on the emission characteristics in late-phase loops. In either of the two processes an EUV late-phase solar flare that conforms to the observational criteria can be numerically synthesized. However, the underlying hydrodynamic and thermodynamic evolutions in late-phase loops are different between the two synthetic flare cases. The late-phase peak due to a long-lasting cooling process always occurs during the radiative cooling phase, while that powered by a secondary heating is more likely to take place in the conductive cooling phase. We then propose a new method for diagnosing the two mechanisms based on the shape of EUV late-phase light curves. Moreover, from the partition of energy input, we discuss why most solar flares are not EUV late flares. Finally, by addressing some other factors that may potentially affect the loop emissions, we also discuss why the EUV late phase is mainly observed in warm coronal emissions.

关键词： Sun: corona Sun: flares Sun:UV radiation

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Study of the Design and Torsion Performance for Carbon Fiber Composite Material Automobile Drive Shaft

Study of the Design and Torsion Performance for Carbon Fiber...

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2016中国汽车工程学会年会暨展览会

作者： Liu Jiancai Xian Yingguo Cao Du Su Jianbo Liao Wei ding mingde Su Zhong Changan Auto R＆D Center Changan Automobile CoLtd

ISBN: (纸本)9789811035272;9789811035265

Based on the classical laminate theory,the stacking structure and its joining structure of a carbon fiber composite drive shaft are designed with the carbon fiber epoxy resin as the *** static torsional performance and its fatigue performance of the drive shaft are analyzed using the finite element *** is showed that the experiment results are consistent with the CAE results in substance,and the drive shaft meets the requirements of the static torque performance and the fatigue performance simultaneously.

关键词： lightweight drive shaft composite carbon fiber design

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A UNIFIED MODEL FOR SOLAR FLARES

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南京大学学报(自然科学) 1999年第4期 496-499页

作者： Chen Pengfei Fang Cheng ding mingde Tang Yuhua (Department of Astronomy,Nanjing University,210093,Nanjing,PRC) DepartmentofAstronomy NanjingUniversity210093NanjingPRC

We performed 2.5-dimensional numerical simulation for two cases,one with the the reconnection point at a high altitude,the other with the reconnection point at a low *** the high-altitude case,the bright loop appears to rise for a long time,with its two footpoints separating and the field lines below the bright loop shrinking,which are all typical features of two-ribbon *** the low-altitude case,the bright loops cease rising only a short time after the impulsive phase of the reconnection and then become rather stable,which shows a large similarity to the compact *** results imply that the two types of solar flares,i.e.,the two-ribbon flares and the compact ones,might be unified into the same magnetic reconnection model,where the height of the reconnection point leads to the bifurcation.

关键词： Sun:flares-MHD-Sun:magnetic fields

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On the standard of Penaeus orientalis culture pond building

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Acta Oceanologica Sinica 1993年第2期12卷 299-308页

作者： Li Mingju, Shi ding, Li mingde,Institute of Marine Culture of Shandong Province , Qingdao, ChinaZhang YongFishery Design Institute of shandong Province China

On the basis of the practical experiences and scientific results in the large scale building of Penaeus orientulis culture pond in the past years, this article puts forward for the first time the main principles and designing standard in the culture pond building from the environmental, ecological, social and economic considerations. It probes systematically into main requirements of the designing scale, farm site selection, arrangement of farm site area, engineering of the pond building, pumping station, water supply and drainage canals and electricity supply engineering of the culture pond.

关键词： On the standard of Penaeus orientalis culture pond building 口口

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Editorial

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Science China(Physics,Mechanics & Astronomy) 2022年第8期65卷 1-1页

作者： Cheng Fang mingde ding Chuan Li PengFei Chen Wei Zhang School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory for Modern Astronomy and Astrophysics Ministry of EducationNanjing 210023China Shanghai Academy of Spaceflight Techonology Shanghai 201109China

The Chinese Hα Solar Explorer(CHASE) was successfully launched on October 14, 2021 as the first solar space mission of China National Space Administration(CNSA). The CHASE mission, dubbed “Xihe” in Chinese(Goddess of the Sun), is designed to test a newly developed satellite platform and to spectroscopically observe the Sun at the Hα line, which is one of the most important optical lines reflecting the dynamics of solar activities in the lower atmosphere.

关键词： Solar reflecting atmosphere.

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