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Earth and Planetary Physics 2020年第2期4卷 120-130页

作者： ruoxian zhou XuDong Gu KeXin Yang GuangSheng Li BinBin Ni Juan Yi Long Chen FuTai Zhao ZhengYu Zhao Qi Wang LiQing zhou Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China

As a dispersive wave mode produced by lightning strokes, tweek atmospherics provide important hints of lower ionospheric(i.e., D-region) electron density. Based on data accumulation from the WHU ELF/VLF receiver system, we develop an automatic detection module in terms of the maximum-entropy-spectral-estimation(MESE) method to identify unambiguous instances of low latitude *** justify the feasibility of our procedure through a detailed analysis of the data observed at the Suizhou Station(31.57°N, 113.32°E) on17 February 2016. A total of 3961 tweeks were registered by visual inspection;the automatic detection method captured 4342 tweeks, of which 3361 were correct ones, producing a correctness percentage of 77.4%(= 3361/4342) and a false alarm rate of 22.6%(= 981/4342).A Short-Time Fourier Transformation(STFT) was also applied to trace the power spectral profiles of identified tweeks and to evaluate the tweek propagation distance. It is found that the fitting accuracy of the frequency–time curve and the relative difference of propagation distance between the two methods through the slope and through the intercept can be used to further improve the accuracy of automatic tweek identification. We suggest that our automatic tweek detection and analysis method therefore supplies a valuable means to investigate features of low latitude tweek atmospherics and associated ionospheric parameters comprehensively.

关键词： tweeks automatic detection WHU-VLF receiver

A detailed investigation of low latitude tweek atmospherics observed by the WHU ELF/VLF receiver:*** features and associated ionospheric parameters

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Earth and Planetary Physics 2020年第3期4卷 238-245页

作者： Juan Yi XuDong Gu Wen Cheng XinYue Tang Long Chen BinBin Ni ruoxian zhou ZhengYu Zhao Qi Wang LiQing zhou Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China

As a companion paper to zhou RX et al.(2020),this study describes application of the automatic detection and analysis module to identify all the tweek atmospherics detectible in the WHU ELF/VLF receiver data collected at Suizhou station during the period of 3 February through 29 February *** analysis of the identified low-latitude tweek events reveals that the occurrence rate varies considerably—from 800 to 6000 tweeks per day,and exhibits a strong diurnal and local time dependence,the peak occurring before local *** diurnal variation of identified tweeks was similar to that of the lightning data obtained by the World-Wide Lightning Location Network(WWLLN)..Estimates of the propagation distance and ionospheric reflection height of tweek atmospherics suggest that the majority(~92%)of the low latitude tweeks originate from the lightning activity within a radius of 4000 km and that they are very likely to reflect from the lower ionospheric D-region at the height range of 75–85 *** these lower ionospheric reflection altitudes,~74%of the corresponding electron densities from the tweek spectral measurements are within 24.5–27.5 cm^-*** daily variation of estimated D-region electron densities in the considered period(February 2016)also exhibits a small overall increasing trend from early to later in the month.

关键词： ionospheric D-region electron density tweek atmospherics

Simultaneous occurrence of four magnetospheric wave modes and the resultant combined scattering effect on radiation belt electrons

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Earth and Planetary Physics 2022年第6期6卷 563-575页

作者： YiWen Zhao Zheng Xiang XuDong Gu BinBin Ni Xin Ma YueQun Lou LuHuai Jiao ruoxian zhou DeYu Guo YangXiZi Liu JunHu Dong Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China Institute of Space Science and Applied Technology Harbin Institute of TechnologyShenzhen 518005China

We report a representative concurrent event of four wave modes at L≈5.0,including electrostatic electron cyclotron harmonic(ECH)waves,exohiss,magnetosonic(MS)waves,and electromagnetic ion cyclotron(EMIC)waves,based on the observations from Van Allen Probe A on October 15,*** diffusion coefficients induced by these waves are calculated by using both the Full Diffusion Code and test particle ***,the scattering effects of these waves on energetic electrons are simulated by using a two-dimensional Fokker-Planck diffusion *** results show that ECH waves mainly scatter low-pitch-angle(60°);and EMIC waves scatter only>5 MeV *** combined scattering effects of exohiss and MS waves are stronger than those of exohiss *** top-hat pitch angle distributions produced by exohiss are relaxed after adding the effect of MS *** the energies of electrons scattered by ECH waves and EMIC waves are much lower and higher than those scattered by exohiss and MS waves,respectively,the combined scattering effects with the addition of ECH and EMIC waves show little difference from the results for the combination of MS waves and *** results suggest that distinct wave modes can occur simultaneously and scatter electrons in combination or individually,which requires careful consideration in future global simulations of the complex dynamics of radiation belt energetic electrons.

关键词： ECH waves exohiss MS waves EMIC waves radiation belts

Convenient Self-Heating Instant Food Causes Significant Increasing Human Exposure to Organophosphate Esters

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Environment & Health 2024年第1期2卷 52-61页

作者： Xiaomin Li Yuhan Yin Wei zhou Hongting Li Boyuan Hu Yajing Cui ruoxian zhou Peilong Wang Jianjie Fu Institute of Quality Standard and Testing Technology for Agro-Products The Chinese Academy of Agricultural Sciences(CAAS)Beijing 100081China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

The self-heating lunch box(SHLB)is a kind of popular instant food in China,yet little is known about the associated chemical release risk during its heating *** this study,we investigated organophosphate esters(OPEs)in original unheated food(UF),SHLB-heated processed food(HF)and potential OPE release from SHLB packaging *** higher concentrations of OPEs were observed in HF(267±246 ng/g dry weight(dw))than in UF(163±211 ng/g dw)(p<0.001),suggesting an introduction of additional OPEs during heating ***(2-chloroethyl)phosphate,triethyl phosphate,and tris(2-chloroisopropyl)phosphate exhibited the highest absolute increased amounts,with 137,48.8,and 149%growth in HF than in UF,*** testing revealed that packaging materials were rich in OPEs and can release considerable OPEs into food simulates(range,14.7-90.8 ng/g;mean,47.9±21.8).Influencing factors(temperature,contact time,oily food)on OPE migration from packaging materials to food were *** temperature and longer contact time increased OPE contents in food ***,the presence of abundant OPEs in UF and significant correlations among different OPEs(p<0.05)suggested contamination happened during food processing and *** one SHLB meal a day,a 12-fold increase of OPE intake was observed for humans compared to those following a traditional dietary *** the high-exposure(95th percentile)scenario,hazard quotients of nine OPEs ranged from 0.00005 to *** results suggested that the SHLB exposure pathway of OPEs should be particularly paid attention to in specific subpopulations that prefer this dietary habit.

关键词： Organophosphate esters Self-heating lunch box Migration influencing factors Human exposure

Triangulation of red sprites observed above a mesoscale convective system in North China

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Earth and Planetary Physics 2019年第2期3卷 111-125页

作者： YongPing Wang GaoPeng Lu Ming Ma HongBo Zhang YanFeng Fan GuoJin Liu ZheRun Wan Yu Wang Kang-Ming Peng ChangZhi Peng FeiFan Liu BaoYou Zhu BinBin Ni XuDong Gu Long Chen Juan Yi ruoxian zhou University of Science and Technology of China School of Earth and Space Science Key Laboratory of Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Wuhan NARI Limited Liability Company State Grid Electric Power Research Institute Department of Physics National Cheng Kung University Department of Space Physics School of Electronic Information Wuhan University

The triangulation of red sprites was obtained, based on concurrent observations over a mesoscale convective system(MCS) in North China from two stations separated by about 450 km. In addition, broadband sferics from the sprite-producing lightning were measured at five ground stations, making it possible to locate and identify the individual causative lightning discharges for different elements in this dancing sprite event. The results of our analyses indicate that the sprites were produced above the trailing stratiform region of the MCS, and their parent strokes were located mainly in the peripheral area of the stratiform. The lateral offset between sprites and causative strokes ranges from a few km to more than 50 km. In a particularly bright sprite, with a distinct halo feature and streamers descending down to an altitude of approximately 48 km, the sprite current signal identified in the electric sferic, measured at a range of about 1,110 km, peaked at approximately 1 ms after the return stroke.

关键词： sprite triangulation peak current hybrid location

基于卡方分布函数的辐射带电子蝴蝶状投掷角分布的优化判别方法

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地球物理学报 2022年第3期65卷 809-818页

作者：罗琼倪彬彬曹兴顾旭东易娟郭英杰郭德宇周若贤龙敏义武汉大学电子信息学院空间物理系武汉430072 中国科学院比较行星学卓越创新中心合肥230026

受不同物理过程影响,辐射带电子呈现多种投掷角分布类型,其中蝴蝶状分布尤为引人关注,其特征为通量在90°投掷角附近有极小值、在较低投掷角处达到峰值.现有研究普遍通过对几个特定投掷角间的通量比值进行限定来识别蝴蝶状分布,然而,该... 详细信息

受不同物理过程影响,辐射带电子呈现多种投掷角分布类型,其中蝴蝶状分布尤为引人关注,其特征为通量在90°投掷角附近有极小值、在较低投掷角处达到峰值.现有研究普遍通过对几个特定投掷角间的通量比值进行限定来识别蝴蝶状分布,然而,该方法所挑选的电子分布并不一定符合蝴蝶状分布特征,这为准确研究电子蝴蝶状分布的现象学规律及其背后物理机制带来了一定困难.针对该问题,本文建立了一个基于卡方分布函数的判别模型,通过比较电子观测通量剖面与模型模拟的理想蝴蝶状分布剖面的相似性来判别电子蝴蝶状分布.使用范艾伦卫星上REPT仪器提供的L-shell>3空间区域内两组不同投掷角分辨率的电子通量数据对该判别方法进行验证,结果表明该方法能明显提升判别效果,分别使基于17个投掷角和36个投掷角的电子通量数据判别蝴蝶状分布的误判率下降12.6%和27.5%.本文的分析结果证实了提高投掷角精度有利于准确确定辐射带电子的投掷角分布类型,发展的模型方法也对深入开展地球与行星磁层中电子蝴蝶状分布的统计学研究具有重要价值.

关键词：辐射带电子蝴蝶状投掷角分布卡方分布函数优化判别

基于深度学习的内磁层等离子体密度动态演化模型

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地球物理学报 2022年第6期65卷 1931-1939页

作者：郭英杰倪彬彬付松胡泽骏郭建广冯明航周若贤郭德宇闫玲马新顾旭东武汉大学电子信息学院空间物理系武汉430072 中国科学院比较行星学卓越创新中心合肥230026 中国极地研究中心国家海洋局极地科学重点实验室上海200136 中国气象局国家空间天气监测预警中心北京100081

等离子体密度作为空间环境的重要参量,它的全球实时分布信息不仅对理解内磁层带电粒子时空演化过程具有重要意义,对于预报和防范灾害性空间天气过程也有着潜在应用价值.利用范阿伦双星的高质量等离子体密度观测数据,本文基于机器学习算... 详细信息

等离子体密度作为空间环境的重要参量,它的全球实时分布信息不仅对理解内磁层带电粒子时空演化过程具有重要意义,对于预报和防范灾害性空间天气过程也有着潜在应用价值.利用范阿伦双星的高质量等离子体密度观测数据,本文基于机器学习算法训练得到一个稳定的深度神经网络模型:包含五个隐藏层;激活函数包括Sigmoid和ReLU函数;以太阳风参数、地磁指数以及卫星对应的位置信息作为输入.在测试集上,该模型输出值和观测值之间的线性相关系数约为0.93,均方根误差(RMSE)约为0.3,表明该模型性能良好.通过使用该模型对2012年4月24日磁暴事件中等离子体密度的全球动态变化进行模拟,我们成功重构了磁暴期间内磁层等离子体密度的全球变化过程,包括等离子体层的侵蚀和恢复,以及羽流的形成和消失.该内磁层等离子体密度的深度神经网络模型将有助于推动内磁层波粒相互作用的深入研究.

关键词：范阿伦卫星地球磁层神经网络模型等离子体密度

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Interfacial Zn2+-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao zhou Xiongbin Luo Hang Li Shan Guo Zhuang Tong Xiaotao zhou Xu Li Zhaohui Hou Shuquan Liang Guozhao Fang College of Mechanical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University College of Materials and Metallurgy Guizhou University National Energy Metal Resources and New Materials Key Laboratory Central South University

Aqueous zinc-ion batteries （AZIBs） are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc （Zn） deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn2+-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups （such as hydroxyl,carboxyl,etc.） have the potential to significantly optimize the solvation structure of Zn2+and regulate the interfacial electric double layer （EDL）.By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn （H-Zn） anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH4V4O10（NVO） full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A *** study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Aqueous zinc-ion batteries Interfacial reaction Asymptotic nucleation model Reversible and stable Zn anode

A low redox potential and long life organic anode material for sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 557-564页

作者： Zhi Li Yang Wei Kang zhou Xin Huang Xing zhou Jie Xu Taoyi Kong Junwei Lucas Bao Xiaoli Dong Yonggang Wang Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) Fudan University Department of Chemistry Boston College School of Materials Science and Engineering Anhui University of Technology

Sodium-ion batteries （SIBs） with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ***,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials（>1 V）.Organic electrodes with low redox potential that can be used as anode are ***,a novel organic anode material （tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na4TDC） has been developed with low redox potential （<0.7 V） and excellent cyclic *** three-sodium storage mechanism was demonstrated with various in-situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per ***,the Na4TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg *** pairing with a thick Na3V2（PO4）3cathode (20.6 mg cm-2),the as-fabricated full cell exhibited high operating voltage （2.8 V）,excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na4TDC anode material for SIBs.

关键词： Organic anode material Low redox potential Composite anode Sodium-ion batteries

Fine-tuning the spatial allocation of phytohormones for smart canopy, smart breeding, and smart agriculture

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Science China Life Sciences 2025年第1期 309-310页

作者： Tao zhou Lin Li National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University HuBei HongShan Laboratory

The dual challenges of global climate change and population growth have increased demand for higher crop yields per unit area. The innovative technology of smart agriculture aims to synergize breeding, cultivation, and production through the application of biological and informatics technologies. Historically, the “Green Revolution” introduced semidwarf varieties of certain key crops by utilizing mutations affecting gibberellin pathways, which significantly increased planting densities and yields.

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