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A Localization Method of High Energy Transients for All-sky Gamma-ray Monitor

Research in Astronomy and Astrophysics 2024年第10期24卷 25-35页

作者： Yi Zhao Wangchen Xue Shaolin Xiong Qi Luo Yuanhao Wang Jiacong Liu Heng Yu Xiaoyun Zhao Yue Huang Jinyuan Liao Jianchao Sun Xiaobo Li Qibin Yi Ce Cai Shuo Xiao Shenglun Xie Chao Zheng Yanqiu Zhang Chenwei Wang Wenjun Tan Zhiwei Guo Chaoyang Li Zhenghua An Gang Chen Yanqi Du Min Gao Ke Gong Dongya Guo jiang He Jianjian He Bing Li Gang Li Xinqiao Li Jing Liang Xiaohua Liang Yaqing Liu Xiang Ma Rui Qiao Liming Song Xinying Song Xilei Sun Jin Wang Ping Wang Xiangyang Wen Hong Wu Yanbing Xu Sheng Yang Dali Zhang Fan Zhang Hongmei Zhang Peng Zhang Shu Zhang Zhen Zhang Shijie Zheng Keke Zhang Xingbo Han Haiyan Wu Hu Tai Hao Geng gaopeng Lu Wei Xu Fanchao Lyu Hongbo Zhang Fangjun Lu Shuangnan Zhang Department of Astronomy Beijing Normal UniversityBeijing 100875China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China College of Physics Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Institute of Astrophysics Central China Normal UniversityWuhan 430079China College of physics Sciences Technology Hebei UniversityBaoding 071002China Physics and Space Science College China West Normal UniversityNanchong 637002China School of Computing and Artificial Intelligence Southwest Jiaotong UniversityChengdu 611756China College of Electronic and information Engineering Tongji UniversityShanghai 201804China Innovation Academy for Microsatellites of Chinese Academy of Sciences Shanghai 201304China National Space Science Center Chinese Academy of SciencesBeijing 100190China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Electronic Information School Wuhan UniversityWuhan 430072China Key Laboratory of Transportation Meteorology of China Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210000China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Fast and reliable localization of high-energy transients is crucial for characterizing the burst properties and guiding the follow-up *** based on the relative counts of different detectors has been widely used for all-sky gamma-ray *** are two major methods for this count distribution localization:χ^(2)minimization method and the Bayesian *** we propose a modified Bayesian method that could take advantage of both the accuracy of the Bayesian method and the simplicity of the χ^(2)*** comprehensive simulations,we find that our Bayesian method with Poisson likelihood is generally more applicable for various bursts than the χ^(2)method,especially for weak *** further proposed a location-spectrum iteration approach based on the Bayesian inference,which could alleviate the problems caused by the spectral difference between the burst and location *** method is very suitable for scenarios with limited computation resources or timesensitive applications,such as in-flight localization software,and low-latency localization for rapidly follow-up observations.

关键词： methods:data analysis methods:analytical (stars:)gamma-ray burst:general

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Propagation of positive, negative, and recoil leaders in upward lightning flashes

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Earth and Planetary Physics 2019年第2期3卷 102-110页

作者： XiuShu Qie ShanFeng Yuan HongBo Zhang RuBin jiang ZhiJun Wu MingYuan Liu ZhuLing Sun YunJiao Pu JinLiang Li Abhay Srivastava ZiLong Ma gaopeng Lu Key Laboratory of Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric Science Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of information Science & Technology College of Earth and Planetary Science University of Chinese Academy of Sciences Fujian Meteorological Service Center Fujian Meteorological Bureau

Leader propagation is a fundamental issue in lightning physics. The propagation characteristics of positive leaders and negative leaders are summarized and compared based on data from high-speed camera and electromagnetic field in rocket-triggered lightning and tower-initiated lightning discharges; available channel base current data recorded in rocket-triggered lightning are also used. The negative leaders propagate in a stepped fashion accompanied by many branches. The stems ahead of the negative leader tip determine the manner and direction of the leader propagation, and even the branching and winding of the lightning channel. The impulsive current, electromagnetic field, and related optical images suggest that the positive leader may develop in a step-like fashion at its initial stage of triggered lightning. However, the stepping processes of the positive leader are obviously different from those of the negative leader. Tower-initiated lightning revealed that the most conspicuous characteristics of the stepwise positive leader involve the intermittent brush-like corona zone in front of the leader tip and the luminosity enhancement of the channel behind the tip. In rockettriggered lightning flashes, the charge transferred during an individual step for the negative leader was nearly an order greater than for the positive counterpart. The successive streamers ahead of the leader tip are essential for both negative and positive leader propagation, and the stems could be formed from one or more streamers in the previous negative streamer zone with the main leader channel dim. High-resolution observation of tower lightning also revealed a new type of bidirectional recoil leader, with polarity contrary to the traditional one, traversing in negative channels associated with tower-initiated and rocket-triggered lightning.

关键词： lightning propagation negative leader positive leader recoil leader

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篦子三尖杉的生物碱成分及其抗肿瘤活性研究

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黑龙江八一农垦大学学报 2024年第2期36卷 84-89,126页

作者：姜春宇高贵文王璇马高鹏孙雯谈佳沂贾桂燕华会明韩通赵蕊黑龙江八一农垦大学生命科学技术学院大庆163319 沈阳药科大学中药学院

为研究篦子三尖杉的化学成分,利用多种色谱分离技术和波谱手段,从其乙醇提取物中分离鉴定了11个生物碱类成分。其中博落回碱(7)、(2Z)-1,2-二氢-2-(1H-吲哚-3-亚甲基)-3H-吲哚-3-酮(8)、1-甲氧基-3-吲哚乙腈(9)、4-甲氧基-1H-吲哚-3-甲... 详细信息

为研究篦子三尖杉的化学成分,利用多种色谱分离技术和波谱手段,从其乙醇提取物中分离鉴定了11个生物碱类成分。其中博落回碱(7)、(2Z)-1,2-二氢-2-(1H-吲哚-3-亚甲基)-3H-吲哚-3-酮(8)、1-甲氧基-3-吲哚乙腈(9)、4-甲氧基-1H-吲哚-3-甲醛(10)、吲哚-3-甲醛(11)为首次从三尖杉属植物中分离得到。采用CCK-8法测试了化合物1~11对人乳腺癌细胞株MCF-7、人肝癌细胞株HepG2和人肺癌细胞株A549的体外抗增殖能力,异三尖杉酯碱(1)和三尖杉酯碱(2)对三种肿瘤细胞显示了显著的抗增殖活性。

关键词：篦子三尖杉生物碱抗肿瘤活性

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A Review of Atmospheric Electricity Research in China from 2019 to 2022

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Advances in Atmospheric Sciences 2023年第8期40卷 1457-1484页

作者： Weitao LYU Dong ZHENG Yang ZHANG Wen YAO Rubin jiang Shanfeng YUAN Dongxia LIU Fanchao LYU Baoyou ZHU gaopeng LU Qilin ZHANG Yongbo TAN Xuejuan WANG Yakun LIU Shaodong CHEN Lyuwen CHEN Qingyong LI Yijun ZHANG State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Laboratory of Lightning Physics and Protection Engineering Chinese Academy of Meteorological SciencesBeijing 100081China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Transportation Meteorology of China Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210041China Chinese Academy of Sciences Key Laboratory of Geospace Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044China Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200030China Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510641China Beijing Key Lab of Transportation Data Analysis and Mining Beijing Jiaotong UniversityBeijing 100044China Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China

Atmospheric electricity is composed of a series of electric phenomena in the *** advances in atmospheric electricity research conducted in China have been achieved in recent *** this paper,the research progress on atmospheric electricity achieved in China during 2019-22 is reviewed focusing on the following aspects:(1)lightning detection and location techniques,(2)thunderstorm electricity,(3)lightning forecasting methods and techniques,(4)physical processes of lightning discharge,(5)high energy emissions and effects of thunderstorms on the upper atmosphere,and(6)the effect of aerosol on lightning.

关键词： atmospheric electricity thunderstorm lightning lightning detection lightning physics

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Understanding the dynamical-microphysical-electrical processes associated with severe thunderstorms over the Beijing metropolitan region

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Science China Earth Sciences 2021年第1期64卷 10-26页

作者： Xiushu QIE Shanfeng YUAN Zhixiong CHEN Dongfeng WANG Dongxia LIU Mengyu SUN Zhuling SUN Abhay SRIVASTAVA Hongbo ZHANG Jingyu LU Hui XIAO Yongheng BI Liang FENG Ye TIAN Yan XU Rubin jiang Mingyuan LIU Xian XIAO Shu DUAN Debin SU Chengyun SUN Wenjing XU Yijun ZHANG gaopeng LU Da-Lin ZHANG Yan YIN Ye YU Key Laboratory of Middle Atmosphere and Global Environment Observation(LAGEO) Institute of A tmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China College of Atmospheric Science Chengdu University of Information TechnologyChengdu 610225China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science&TechnologyNanjing 210044China Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Earth and Planetary Science University of Chinese Academy of ScienceBeijing 100049China Meteorological Observation Centre Beijing Meteorological BureauBeijing 100081China jiangxi Weather Modification Nanchang 330096China Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Department of Atmospheric and Oceanic Science University of MarylandMaryland 20742USA

The Dynamical-microphysical-electrical Processes in Severe Thunderstorms and Lightning Hazards(STORM973)project conducted coordinated comprehensive field observations of thunderstorms in the Beijing metropolitan region(BMR)during the warm season from 2014 to *** aim of the project was to understand how dynamical,microphysical and electrical processes interact in severe thunderstorms in the BMR,and how to assimilate lightning data in numerical weather prediction models to improve severe thunderstorm *** platforms used in the field campaign included the Beijing Lightning Network(BLNET,consisting of 16 stations),2 X-band dual linear polarimetric Doppler radars,and 4 laser raindrop *** collaboration also made use of the China Meteorological Administration’s mesoscale meteorological observation network in the Beijing-Tianjin-Hebei *** diverse thunderstorm types were documented,it was found that squall lines and multicell storms were the two major categories of severe thunderstorms with frequent lightning activity and extreme rainfall or unexpected local short-duration heavy rainfall resulting in inundations in the central urban area,influenced by the terrain and environmental *** flash density maximums were found in eastern Changping District,central and eastern Shunyi District,and the central urban area of Beijing,suggesting that the urban heat island effect has a crucial role in the intensification of thunderstorms over *** addition,the flash rate associated with super thunderstorms can reach hundreds of flashes per minute in the central city *** super(5%of the total),strong(35%),and weak(60%)thunderstorms contributed about 37%,56%,and 7%to the total flashes in the BMR,*** to the close connection between lightning activity and the thermodynamic and microphysical characteristics of the thunderstorms,the lightning flash rate can be used as an indicator of severe weather events,such as hail

关键词： Lightning 3D location Dual linear polarimetric Doppler radar Severe thunderstorm Lightning data assimilation Hail Short-term heavy precipitation

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反爆炸反应装甲串联爆炸成型弹丸匹配设计方法

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兵工学报 2020年第12期41卷 2369-2378页

作者：门建兵聂源蒋建伟王树有冯高鹏北京理工大学爆炸科学与技术国家重点实验室北京100081 中国工程物理研究院总体工程研究所四川绵阳621999

针对反爆炸反应装甲(ERA)串联爆炸成型弹丸(EFP)成型设计问题,建立串联EFP引爆能力、分离时序和侵彻能力的理论条件。采用ERA引爆判据、EFP速度衰减理论和侵彻理论,分析形状、质量比和速度差对引爆能力、分离时序和侵彻能力影响规律。... 详细信息

针对反爆炸反应装甲(ERA)串联爆炸成型弹丸(EFP)成型设计问题,建立串联EFP引爆能力、分离时序和侵彻能力的理论条件。采用ERA引爆判据、EFP速度衰减理论和侵彻理论,分析形状、质量比和速度差对引爆能力、分离时序和侵彻能力影响规律。基于作用场时间τe≤1500μs的典型ERA,在飞行距离H≤1000∅(∅为装药口径)时,获得串联EFP成型特征的必要条件,其中:球-杆组合型,前后EFP直径比d_(f)/d_(r)≤1.09,前EFP质量与总质量之比0.17

关键词：反爆炸反应装甲串联爆炸成型弹丸匹配设计分离时序

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钯催化α-取代苄腈与支链烯丙基碳酸酯的烯丙基烷基化反应

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有机化学 2020年第10期40卷 3399-3409页

作者：张高鹏江阳杰丁昌华侯雪龙中国科学院上海有机化学研究所金属有机化学国家重点实验室上海200032 上海大学化学系上海200444 中国科学院上海有机化学研究所上海-香港化学合成联合实验室上海200032 中国科学院大学北京100049

报道了钯催化下α-取代苄腈作为亲核试剂,与支链烯丙基碳酸酯的烯丙基烷基化反应,在易得的大位阻氮杂环卡宾配体存在下,以良好的收率、区域选择性及非对映选择性得到支链烯丙基烷基化产物.

关键词：钯苄腈支链烯丙基碳酸酯烯丙基烷基化

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电阻率法研究引气剂对水泥浆体化学收缩及氯离子渗透性的影响

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功能材料 2019年第2期50卷 2208-2213页

作者：郭大卫廖宜顺江国喜刘高鹏武汉科技大学城市建设学院武汉430065

研究了引气剂对硅酸盐水泥浆体的电阻率、化学收缩、物理力学性能及氯离子渗透性的影响。结果表明,掺入引气剂使水泥浆体的流动度增大,凝结时间延长,早期水化速率加快,化学收缩增大。水泥浆体的电阻率在凝结前随着引气剂掺量的增加而增... 详细信息

研究了引气剂对硅酸盐水泥浆体的电阻率、化学收缩、物理力学性能及氯离子渗透性的影响。结果表明,掺入引气剂使水泥浆体的流动度增大,凝结时间延长,早期水化速率加快,化学收缩增大。水泥浆体的电阻率在凝结前随着引气剂掺量的增加而增大,在硬化后则随着掺量的增加而减小。在28d龄期时,0.04%掺量内的引气剂对硬化浆体的抗压强度影响较小,其强度损失率低于5%,氯离子迁移系数随掺量的增大而减小。随引气剂掺量的变化,水泥浆体的电阻率与化学收缩、抗压强度和氯离子迁移系数均存在很好的定量关系。通过水泥浆体的电阻率发展曲线可以预测其化学收缩、强度与氯离子渗透性的变化规律。

关键词：引气剂电阻率化学收缩氯离子渗透性

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苯并[a]芘和菲对缢蛏血细胞DNA损伤的研究

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生态毒理学报 2015年第3期10卷 281-287页

作者：蒋玫李磊沈新强许高鹏杨杰青中国水产科学研究院东海水产研究所上海200090 上海海洋大学上海203360

为研究苯并[a]芘和菲对缢蛏的毒性效应,将缢蛏(Sinonovacula constricta)分别暴露于浓度为0.45 mg·L-1、0.15 mg·L-1、0.05 mg·L-1苯并[a]芘溶液和0.45 mg·L-1、0.15 mg·L-1、0.05 mg·L-1菲的溶液中,采用单细胞凝胶电泳实验(彗星... 详细信息

为研究苯并[a]芘和菲对缢蛏的毒性效应,将缢蛏(Sinonovacula constricta)分别暴露于浓度为0.45 mg·L-1、0.15 mg·L-1、0.05 mg·L-1苯并[a]芘溶液和0.45 mg·L-1、0.15 mg·L-1、0.05 mg·L-1菲的溶液中,采用单细胞凝胶电泳实验(彗星实验)技术检测不同暴露时间缢蛏血淋巴细胞的DNA损伤程度,对照组为清洁海水。结果显示,高浓度(0.45 mg·L-1)苯并[a]芘溶液和(0.45 mg·L-1)菲溶液在短期(7 d)内即可导致缢蛏血细胞显著的DNA损伤,并且随苯并芘[a]和菲浓度的增大和暴露时间的延长,DNA损伤程度增加。21 d恢复实验后,各浓度组DNA损伤又均有不同程度的恢复,但中高浓度组(0.45 mg·L-1和0.15 mg·L-1)与对照组仍显著性差异。两种多环芳烃物质对缢蛏血细胞的DNA损伤作用均存在较显著时间-剂量-效应关系。其中,苯并芘[a]对缢蛏血细胞的DNA损伤作用要高于菲。

关键词：苯并芘[a]和菲缢蛏血细胞 DNA损伤单细胞凝胶电泳彗星实验

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基于综合生物标志物响应指数评价0#柴油和平湖原油胁迫下的缢蛏（Sinonovacula constricta）毒性效应

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环境科学学报 2015年第4期35卷 1174-1182页

作者：蒋玫李磊沈新强吴庆元牛俊翔许高鹏中国水产科学研究院东海水产研究所上海200090 上海海洋大学上海203360

选择0#柴油和平湖原油乳化液对缢蛏(Sinonovacula constricta)进行氧化胁迫实验,选取典型的抗氧化酶-超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷光甘肽硫转移酶(GST)及过氧化物酶(POD)用于衡量油类污染物对生物体造成的氧化压力大小.此... 详细信息

选择0#柴油和平湖原油乳化液对缢蛏(Sinonovacula constricta)进行氧化胁迫实验,选取典型的抗氧化酶-超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷光甘肽硫转移酶(GST)及过氧化物酶(POD)用于衡量油类污染物对生物体造成的氧化压力大小.此外,结合综合生物标志物响应(Integrated Biomarker Responses,IBR)指标,对2种石油污染物对缢蛏的毒性响应进行定量化评价.结果表明,不同浓度的0#柴油和平湖原油对缢蛏消化腺中的4种酶表现出不同程度的诱导效应,各试验组在暴露前期均表现出诱导或抑制,但对4种酶的影响存在时间顺序性,SOD、CAT和GST的酶活性表现为升高-降低的过程,POD表现为降低-升高的过程,活性达到峰值的时间SOD和CAT要早于GST和POD.结合计算出的IBR数值来看,高浓度0#柴油能够引起最为显著的生物效应变化,显示该石油污染物高毒性的特征,0#柴油生物毒性大于平湖原油生物毒性.

关键词：缢蛏(Sinonovacula constricta) 0#柴油平湖原油抗氧化酶综合生物标志物响应指标

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