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Skara hunanensis a new species of Skaracarida (Crustacea) from Upper Cambrian (Furongian) of Hunan,south china

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Progress in Natural Science:Materials International 2007年第8期17卷 934-942页

作者： liu Jie dong xiping~(**) (school of earth and space Science,peking university,beijing 100871,china) school of earth and space Science Peking University Beijing 100871 China

The fossils of Orsten-type preservation are as famous as Chengjiang Fauna in the world,but it was not until 2005 that the Orsten-type fossils represented by Skaraearida and Phosphatocopida were first reported to be found in western Hunan,South china. Here,we report the systematic paleontology of all the exquisitely preserved specimens belonging to *** were found at a same horizon of Upper Cambrian (Furongian) in Wangcun section,western Hunan,south china,assigned to a new species Skara huna- nensis *** hunanensis is characterized by small,soft-integumented,marine forms with slender,annulate body;labrum large and ventrocaudally directed;uniramous antennulae;biramous antennae and mandibulae;maxillas and maxillipeds of the same shape;all postantennular limbs join a short cephalic filter *** body has two tagmata:a cephalon with five pairs of well developed ap- pendages and a trunk composed of 11 ring-shaped conical segments.

关键词： Skara hunanensis Skaracarida Crustacea Upper Cambrian Furongian Hunan

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

New hybrid algorithm for land surface temperature retrieval from multiple-band thermal infrared image without atmospheric and emissivity data inputs

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International Journal of Digital earth 2020年第12期13卷 1430-1453页

作者： Huazhong Ren Jiaji dong Rongyuan liu Yitong zheng Jinxin Guo Shanshan Chen Jing Nie Yan Zhao Institute of Remote Sensing and Geographic Information System School of Earth and Space SciencesPeking UniversityBeijingPeople’s Republic of China china Aero Geophysical Survey and Remote Sensing Center for Natural Resources BeijingPeople’s Republic of China china Translation Telecommunications and Information Center BeijingPeople’s Republic of China

Land surface temperature(LST)retrieval from thermal infrared(TIR)remote sensing image requires atmospheric and land surface emissivity(LSE)data that are sometimes *** overcome this problem,a hybrid algorithm is developed to retrieve LST without atmospheric correction and LSE data input,by combining the split-window(SW)and temperature–emissivity separation(TES)*** SW algorithm is used to estimate surface-emitting radiance in adjacent TIR bands,and such radiance is applied to the TES algorithm to retrieve LST and *** hybrid algorithm is implemented on five TIR bands of the Advanced spaceborne Thermal Emission and Reflection Radiometer(ASTER).Analysis shows that the hybrid algorithm can estimate LST and LSE with an error of 0.5–1.5 K and 0.007–0.020,***,the LST error of the hybrid algorithm is equivalent to that of the original ASTER TES algorithm,involving 1%–2%uncertainty in atmospheric *** hybrid algorithm is validated using ground-measured LST at six sites and ASTER LST products,indicating that the temperature difference between the ASTER TES algorithm and the hybrid algorithm is 1.4 K and about 2.5–3.5 K compared to the ground ***,the hybrid algorithm is applied to at two places.

关键词： Land surface temperature and emissivity TES algorithm split-window algorithm hybrid algorithm

Methane formation from CaCO_3 reduction catalyzed by high pressure

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Chinese Chemical Letters 2008年第4期19卷 475-478页

作者： Jin Yang Chen Lu Jiang Jin Jun Ping dong Hai Fei zheng Gui Yang liu school of Environmental and Chemical Engineering Shanghai UniversityShanghai 201800China school of sciences Shanghai UniversityShanghai 200436China school of the earth and space sciences Peking UniversityBeijing 100871China

Under high pressures of several giga-pascals using hydrothermal diamond anvil cell,methane generated directly from CaCO3 reduction in gold-lined chamber is in situ measured by Raman spectroscopy at the temperature of 550℃ Fhe reducing agents include FeO,SiO and natural fayalite（Fe2SiO4）,and the resource of hydrogen are water and natural serpentine（Mg3Si2O5（OH）4）. The study demonstrates the existence of abiogenic formation of methane under high pressures in the earth＇s interior and that the application of high pressure to catalyze multicomponent reactions is a very promising method.

关键词： CaCO3 reduction High pressure Methane Raman spectroscopy

The nearest neutron star candidate in a binary revealed by optical time-domain surveys

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Science china(Physics,Mechanics & Astronomy) 2023年第12期66卷 184-202页

作者： Ling-Lin zheng Mouyuan Sun Wei-Min Gu Tuan Yi Zhi-Xiang Zhang Pei Wang Junfeng Wang Jianfeng Wu Shan-Shan Weng Song Wang Sen-Yu Qi Jia Zhang Chun-Qian Li Jian-Rong Shi Yong Shao Xiang-dong Li Jin-Bo Fu Fan Yang Zhongrui Bai Yu Bai Haotong Zhang Jifeng liu Department of Astronomy Xiamen UniversityXiamen 361005China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Physics Institute of Theoretical PhysicsNanjing Normal UniversityNanjing 210023China Yunnan Observatories Chinese Academy of SciencesKunming 650216China College of Astronomy and space Science University of Chinese Academy of SciencesBeijing 100049China school of Astronomy and space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityNanjing 210023China

The near-earth(within~100 pc)supernova explosions in the past several million years can cause the global deposition of radioactive elements(e.g.,60Fe)on *** remnants of such supernovae are too old to be easily *** is therefore of great interest to search for million-year-old near-earth neutron stars or black holes,the products of ***,neutron stars and black holes are challenging to find even in our Solar neighbourhood if they are not radio pulsars or X-ray/γ-ray *** we report the discovery of one of the nearest(127.7±0.3 pc)neutron star candidates in a detached single-lined spectroscopic binary LAMOST J235456.73+335625.9(hereafter J2354).Utilizing the time-resolved ground-based spectroscopy and space photometry,we find that J2354 hosts an unseen compact object with M_(inv)being 1.4-1.6 M_(⊙).The follow-up Swift ultraviolet(UV)and X-ray observations suggest that the UV and X-ray emission is produced by the visible star rather than the compact ***,J2354 probably harbours a neutron star rather than a hot ultramassive white ***-hour exceptionally sensitive radio follow-up observations with Five-hundred-meter Aperture Spherical radio Telescope fail to reveal any pulsating radio signals at the 6σflux upper limit of 12.5μ***,the neutron star candidate in J2354 can only be revealed via our time-resolved ***,the distance between J2354 and our earth can be as close as~50 pc around 2.5 million years(Myrs)ago,as revealed by the Gaia *** discovery demonstrates a promising way to unveil the hidden near-earth neutron stars in binaries by exploring the optical time domain,thereby facilitating understanding of the metal-enrichment history in our Solar neighbourhood.

关键词： neutron stars binary stars stellar evolution

寒武纪化石胚胎 Markuelia 的肌肉组织

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北京大学学报（自然科学版） 2021年第2期57卷 390-394页

作者：刘腾段佰川刘建波董熙平北京大学地球与空间科学学院北京100871 自然资源部第一海洋研究所海洋地质与成矿作用重点实验室青岛266061

利用同步加速器辐射X射线断层显微技术(SRXTM),研究湖南省王村化石库的化石胚胎Markuelia hunanensis。所研究的标本保存了头部和尾部表皮下的栅栏状结构,对这些结构进行三维重建后,发现栅栏结构为环形,呈两侧对称状排列。将头部和尾部... 详细信息

利用同步加速器辐射X射线断层显微技术(SRXTM),研究湖南省王村化石库的化石胚胎Markuelia hunanensis。所研究的标本保存了头部和尾部表皮下的栅栏状结构,对这些结构进行三维重建后,发现栅栏结构为环形,呈两侧对称状排列。将头部和尾部的栅栏结构分别解释为可能的咽部和尾刺基部的肌肉组织。对可能的肌肉组织结构的进一步研究表明,Markuelia hunanensis最早的胚后阶段可能是小型底栖动物,生活在泥砂缝隙之间,并且可能是活跃的捕食者。

关键词：化石胚胎软组织解剖学肌肉组织 Markuelia 寒武纪

风云3C对不同类型辐射带电子分布变化的观测:2015年3月17日磁暴事件分析

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地球物理学报 2023年第6期66卷 2252-2262页

作者：胡立凡项正顾旭东倪彬彬张效信郭建广张贤国朱昌波郭德宇付松刘阳希子董俊虎赵怡雯武汉大学电子信息学院武汉430072 中国科学院地质与地球物理研究所地球与行星物理重点实验室北京100029 中国气象局国家空间天气监测预警中心北京100081 中国科学院国家空间科学中心北京100190

风云3C卫星(简称FY-3C)测量的低地球轨道(Low earth Orbit,简称LEO)高能粒子(电子、质子和重离子)通量,是空间环境监测预警业务的重要自主数据来源.深入分析风云3C卫星测量的不同种类高能电子的分布特征和变化规律,对辐射带研究和空间... 详细信息

风云3C卫星(简称FY-3C)测量的低地球轨道(Low earth Orbit,简称LEO)高能粒子(电子、质子和重离子)通量,是空间环境监测预警业务的重要自主数据来源.深入分析风云3C卫星测量的不同种类高能电子的分布特征和变化规律,对辐射带研究和空间天气预报具有重要意义.本文使用FY-3C测量的空间粒子数据,系统分析了2015年3月17日强磁暴期间辐射带捕获、准捕获和沉降电子的演化特征及其主导性物理机制.结果表明,在磁暴主相,外辐射带电子通量(E2:0.35~0.65 MeV,E3:0.65~1.2 MeV)出现快速下降,达到两个数量级,E1能级(E1:0.15~0.35MeV)电子通量在L4的区域出现明显下降.在磁暴恢复相,由于合声波(chorus waves)先加速低能段电子,E1能段电子通量最先(小于五小时)开始增加,在磁暴结束时覆盖2105 cm^(-2)·sr^(-1)·s^(-1).电子能段越高通量增长得越慢(E2:十小时内;E3:一天内),最终覆盖的空间范围更小(E2:22.51,E2,E3能段)大幅下降时沉降电子通量并未明显增加,表明此时高能电子(E1,E2,E3能段)的损失机制主要是穿过磁层顶损失,而不是沿着磁力线沉降到中性大气.三种类型的电子通量在磁暴恢复相均出现明显增强,而合声波对电子同时存在加速和散射作用,因此判断恢复相电子的加速机制主要是合声波与电子的回旋共振作用.这些结果表明强磁暴期间辐射带电子呈现出复杂多变的动力学演化特征,风云3C测量的低轨道粒子数据可以为分析辐射带中粒子损失和加速过程中主导的物理机制提供关键信息,是空间辐射环境建模和预测预报的有力支撑.

关键词：风云3C卫星磁暴捕获电子准捕获电子沉降电子

陕西汉南毕机沟钒钛磁铁矿锆石U-Pb年代学及其意义

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地球学报 2017年第4期38卷 505-512页

作者：陈龙耀崔建军刘晓春曲玮李淼郑光高李东东张海峰刘林中国地质科学院地质力学研究所北京100081 北京大学地球科学与空间学院北京100871 陕西省地质矿产勘查开发总公司第二分公司陕西汉中723000 陕西省矿产资源勘查与综合利用重点实验室陕西西安710054

毕机沟钒钛磁铁矿位于扬子板块北缘汉南杂岩的西北部,是基性-超基性杂岩体分异演化的产物。矿区范围出露的岩石主要包括橄长岩、辉长岩、辉长闪长岩和闪长岩,具有明显岩相分带和韵律旋回特征。目前,已发现的多个钒钛磁铁矿体均位于基性... 详细信息

毕机沟钒钛磁铁矿位于扬子板块北缘汉南杂岩的西北部,是基性-超基性杂岩体分异演化的产物。矿区范围出露的岩石主要包括橄长岩、辉长岩、辉长闪长岩和闪长岩,具有明显岩相分带和韵律旋回特征。目前,已发现的多个钒钛磁铁矿体均位于基性岩-超基性杂岩体的辉长岩相带内。本次研究对毕机沟矿区的含矿辉长岩和穿切含矿辉长岩的花岗岩脉进行了原位微区LA-MC-ICPMS锆石U-Pb定年,获得两者的侵位时间分别为(783±4)Ma(MSWD=0.09)和(759±4)Ma(MSWD=1.50),结果表明毕机沟钒钛磁铁矿的成矿时代大约为783 Ma,但不晚于759 Ma。结合前人区域成果资料,毕机沟含钒钛磁铁矿的基性-超基性杂岩体与该区新元古代大规模具岛弧性质的基性-超基性杂岩体的形成时代相近,我们认为毕机沟钒-钛磁铁矿可能形成于活动型大陆边缘环境。

关键词：毕机沟汉南基性-超基性杂岩体钒钛磁铁矿锆石U-Pb年龄

甚低频台站信号对地球内辐射带和槽区能量电子的散射效应分析

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物理学报 2021年第14期70卷 399-409页

作者：刘阳希子项正郭建广顾旭东付松周若贤花漫朱琪易娟倪彬彬武汉大学电子信息学院武汉430072 中国气象局国家空间天气监测预警中心北京100081 中国科学院比较行星学卓越创新中心合肥230026

人工地面甚低频台站发射的10-30 kHz信号主要在地球-低电离层波导传播,部分能量会泄露进入内磁层,进而会影响近地空间中高能电子的动态变化过程.本文详细研究了NWC,NAA和DHO38三个人工甚低频台站信号对内辐射带和槽区高能电子的散射作用... 详细信息

人工地面甚低频台站发射的10-30 kHz信号主要在地球-低电离层波导传播,部分能量会泄露进入内磁层,进而会影响近地空间中高能电子的动态变化过程.本文详细研究了NWC,NAA和DHO38三个人工甚低频台站信号对内辐射带和槽区高能电子的散射作用.基于准线性理论,分别计算了三个甚低频台站信号单独和共同作用时对高能电子的弹跳平均投掷角扩散系数,并进一步利用Fokker-Planck扩散方程模拟内辐射带及槽区的高能电子在200 d内的动态演化过程.结果表明,在低L-shell(L≤1.8),NWC台站信号对电子的损失占主导作用,可以使能量在100 keV附近、投掷角小于60°的电子出现明显损失;在较高的L-shell(2.2≤L≤2.7),主要是NAA和DHO38台站信号占主导作用,可以使能量小于20 keV、投掷角小于70°的电子通量显著下降;三个甚低频台站信号对高投掷角(>80°)的电子均无显著影响.

关键词：地球辐射带人工甚低频台站信号波粒相互作用电子投掷角扩散系数