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Acta Geologica Sinica(English Edition) 2015年第A02期89卷 3-4页

作者： CHEN Mei YANG Jingsui zhang Cong TIAN Zuolin HUANG Jie YU-Huanglu dong Tianci school of earth Science and Mineral Resources China University of Geosciences Beijing 100083 China State Key Laboratory for Continental Tectonics and Dynamics Institute of Geology Chinese Academy of GeologicalSciences Beijing 100037 China MOE Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space Sciences Peking UniversityBeijing 100871 China

The garnet-bearing mica-quartz schist of the Sumdo high pressure metamorphic beltfrom the Lhasa block is mainly composed of garnet, muscovite, albite, quartz and minor chlorite, rutile and sphene.

关键词： RESEARCH Metamorphic rocks Muscovite Mica Chlorite minerals Garnet Schists

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

角度对于Y型分叉断层自发破裂传播过程的影响

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地球物理学报 2019年第11期62卷 4156-4169页

作者：董森张海明北京大学元培学院北京100871 北京大学地球与空间科学学院北京100871

断层的几何形态是地震破裂传播过程的控制因素之一,从而影响着地震的危险性.Y型分叉断层是断层的多种复杂几何形态当中常见的一种,研究断层的分叉特征对震源破裂传播的影响,对于深入认识复杂几何形态断层的动力学特征具有重要意义.本文... 详细信息

断层的几何形态是地震破裂传播过程的控制因素之一,从而影响着地震的危险性.Y型分叉断层是断层的多种复杂几何形态当中常见的一种,研究断层的分叉特征对震源破裂传播的影响,对于深入认识复杂几何形态断层的动力学特征具有重要意义.本文利用边界积分方程方法,模拟了612个分叉面,通过改变分叉断层面的分叉角度来分析断层分叉对传播的影响,并定量分析了分叉面之间以及主断层对分叉面的应力作用机制.模拟结果表明:分叉断层的一个断层分叉的破裂,既受到主断层作用的影响,也受到该断层另一分叉的作用的影响,是两者共同作用的结果.其中,主断层的作用基本上只与该断层分叉与主断层延长面的夹角有关,而与该断层另一分叉关系不大;该断层另一分叉的作用主要与两个断层分叉的夹角有关,但同时也要考虑其破裂状况.对于破裂以超剪切速度到达断层分叉处的情况,主断层对于大角度和小角度分叉的破裂促进作用较强,而对中等角度分叉的破裂促进作用较弱;该断层另一分叉对破裂的作用随着两个断层分叉之间夹角的增加,由强烈的抑制转为促进.

关键词：分叉断层数值模拟边界积分方程方法震源动力学

Changes in different land cover areas and NDVI values in northern latitudes from 1982 to 2015

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Advances in Climate Change Research 2021年第4期12卷 456-465页

作者： XUE Shou-Ye XU Hai-Yan MU Cui-Cui WU Tong-Hua LI Wang-Ping zhang Wen-Xin Irina STRELETSKAYA Valery GREBENETS Sergey SOKRATOV Alexander KIZYAKOV WU Xiao-dong Cryosphere Research Station on the Qinghai-Tibet Plateau State Key Laboratory of Cryospheric ScienceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China school of Environmental and Municipal Engineering Lanzhou Jiaotong UniversityLanzhou730070China Key Laboratory of Western china's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou730000China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519000China university Cooperation of Polar Research Beijing100875China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou511458China university of Chinese Academy of sciences Beijing10049China school of Civil Engineering Lanzhou University of TechnologyLanzhou730050China Department of Physical Geography and Ecosystem Science Lund UniversityLundSE-22362Sweden Center for Permafrost(CENPERM) Department of Geosciences and Natural Resource ManagementUniversity of CopenhagenCopenhagenDK-1165Denmark Geographical Faculty Lomonosov Moscow State UniversityMoscow119991Russia.

Climate warming leads to vast changes in the land cover types and plant biomass in the northern high-latitude *** overall trend is of shrubland and tree lines moving northwards,while changes in different land cover types and vegetation growth in response to climate change are largely ***,we selected land areas with latitudes higher than 50°N as the study *** compared the land cover type changes and explored relationships between the normalized difference vegetation index(NDVI)values of different land cover types,air temperature,and precipitation during 1982-2015 based on dynamic *** results indicated that forest and shrubland areas increased as a large area of grassland shifted to forest and *** snow/ice,tundra and grassland largely have decreased from 1982 to *** approximately 277.3×103 km2 of barren land(6.2%of the total barren land area in 1982)changed to tundra,the tundra area still decreased because some tundra shifted to forest and *** NDVI values of tundra significantly increased,but the shrubland showed a decreasing *** in the growing season(June to September)showed the largest positive correlation coefficients with the NDVI values of forest,tundra,grassland,and ***,due to shrubification processes and plant mortality in shrubland areas,the shrubland NDVI showed negative relationship with annual temperature but positively correlated with monthly *** together,although there is large room for improvement of the land cover type data accuracy,our results suggested that the land cover types in high-latitude regions changed significantly,while the NDVI values of the different land cover types showed different responses to climate change.

关键词： Air temperature Arctic Climate change Precipitation NDVI

GIScience and remote sensing in natural resource and environmental research:Status quo and future perspectives

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Geography and Sustainability 2021年第3期2卷 207-215页

作者： Tao Pei Jun Xu Yu Liu Xin Huang Liqiang zhang Weihua dong Chengzhi Qin Ci Song Jianya Gong Chenghu Zhou State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCAS11ADatun Road AnwaiBeijing 100101China Institute of Remote Sensing and Geographical Information Systems School of Earth and Space SciencesPeking UniversityBeijing 100871China school of Remote Sensing and Information Engineering Wuhan UniversityWuhan 430079China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China university of Chinese Academy of sciences Beijing 100049China

Geographic information science(GIScience)and remote sensing have long provided essential data and method-ological support for natural resource challenges and environmental problems *** increasing advances in information technology,natural resource and environmental science research faces the dual challenges of data and computational ***,the role of remote sensing and GIScience in the fields of natural resources and environmental science in this new information era is a key concern of *** study clarifies the definition and frameworks of these two disciplines and discusses their role in natural resource and environmental *** is the discipline that studies the abstract and formal expressions of the basic concepts and laws of geography,and its research framework mainly consists of geo-modeling,geo-analysis,and *** sensing is a comprehensive technology that deals with the mechanisms of human ef-fects on the natural ecological environment system by observing the earth surface *** main areas include sensors and platforms,information processing and interpretation,and natural resource and environmental *** and remote sensing provide data and methodological support for resource and environmental science *** play essential roles in promoting the development of resource and environmental science and other related *** paper provides forecasts of ten future directions for GIScience and eight future directions for remote sensing,which aim to solve issues related to natural resources and the environment.

关键词： Natural resource Environmental science GIScience Remote sensing Information technology

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对流层臭氧卫星遥感反演综述

地球科学进展 2024年第1期39卷 56-70页

作者：许健张卓饶兰兰王雅鹏闫欢欢胡斯勒图石崇刘嵩格根塔娜王文煜石恩涛姚舜朱军王咏梅董晓龙施建成中国科学院国家空间科学中心北京100190 中国气象局国家卫星气象中心北京100081 中国科学院空天信息创新研究院北京100101 南方科技大学环境科学与工程学院广东深圳518055 航天东方红卫星有限公司北京100081

臭氧是地球大气中最重要的痕量气体之一,在气候变化和生态环境中均扮演着至关重要的角色。对流层臭氧作为光化学烟雾的重要成分之一,其浓度变化与人类活动息息相关。基于卫星遥感技术监测对流层臭氧浓度可以帮助我们更好地发现和定量解... 详细信息

臭氧是地球大气中最重要的痕量气体之一,在气候变化和生态环境中均扮演着至关重要的角色。对流层臭氧作为光化学烟雾的重要成分之一,其浓度变化与人类活动息息相关。基于卫星遥感技术监测对流层臭氧浓度可以帮助我们更好地发现和定量解释对流层臭氧在不同季节、不同时刻以及不同区域的变化特征,探讨臭氧在对流层中的成因机制。随着卫星遥感技术的全面发展,臭氧遥感产品(例如臭氧总量、廓线等)无论在产品精度或是时空分辨率方面均取得了显著进步,然而,由于受较弱卫星信号与复杂下垫面的影响,对流层臭氧遥感产品精度仍无法满足目前对流层大气成分的精细化科学应用研究。主要围绕对流层臭氧卫星遥感,回顾和分析了臭氧卫星遥感载荷的发展历程和现状,结果表明国内外已基于不同谱段(紫外—可见光、热红外和太赫兹)实现了全球及区域臭氧的时空分布探测;讨论了基于不同技术遥感反演算法(直接与间接反演、多波段联合反演、天底—临边协同反演、基于机器学习技术的创新算法等)的特点及适用性,分析表明算法精度的提升包括从复杂大气背景下的辐射传输模拟、基于地面观测的先验信息优化以及仪器定标与信噪比等多方面的工作;展望了卫星遥感在全球和区域尺度提供可靠对流层臭氧观测数据的应用前景,为对流层臭氧污染的形成机理、人类活动与气候变化如何影响对流层臭氧浓度变化等方面的研究提供关键数据支撑。

关键词：卫星遥感对流层臭氧大气反演

搜寻第二个地球——系外地球(ET)巡天计划

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空间科学学报 2024年第3期44卷 400-424页

作者：葛健陈雯陈永和宋宗玺王坚张辉李岩臧伟呈周丹张永帅陈琨阳应权毛淑德黄煦药新雨李兴隆姜海娇于涌唐正宏董峰高伟张鸿飞申超王峰涛魏传新杨宝玉李豫东文林张朋军张聪聪谢基伟马波邓洪平刘慧根段旭亮王昊宇黄江江高扬王伊菲王磊秦根健刘欣宇高婕中国科学院上海天文台上海200030 中国科学院微小卫星创新研究院上海201304 中国科学院上海技术物理研究所上海200083 中国科学院西安光学精密机械研究所西安710119 中国科学技术大学合肥230026 清华大学天文系北京100190 南昆士兰大学天体物理中心图文巴QLD4350 中国航天科技集团公司第八研究院803研究所上海201109 中国科学院新疆理化技术研究所乌鲁木齐830011 南京大学天文系南京210023 中山大学物理与天文学院珠海519082

系外地球科学卫星(ET)将通过采用空间大视场超高精度测光这一关键技术在国际上率先突破生命起源中的系外地球存在及其演化这一重大前沿科学问题. ET卫星将在日地拉格朗日L2点晕(Halo)轨道部署由6台广角凌星望远镜和1台微引力透镜望远镜... 详细信息

系外地球科学卫星(ET)将通过采用空间大视场超高精度测光这一关键技术在国际上率先突破生命起源中的系外地球存在及其演化这一重大前沿科学问题. ET卫星将在日地拉格朗日L2点晕(Halo)轨道部署由6台广角凌星望远镜和1台微引力透镜望远镜构成的空间天文台,结合凌星法和微引力透镜法,利用空间超大视场和超高精度的光学测光观测,首次发现富有重要意义、被广泛关注的系外地球,并确定其发生率,对目前了解甚少的类地行星和流浪行星进行国际上第一次大规模的种群普查,首次发现流浪地球,并确定其发生率,揭示类地行星和流浪行星起源,为地外生命探寻提供候选者和新方向. ET卫星的观测结果、统计研究以及和对理论的检验将回答系外地球在宇宙中有多普遍,类地行星是如何形成和演化的,流浪行星又是如何起源的这些亟待解决的前沿科学问题.对ET卫星发现的系外地球样本的后随观测,将精确测量其质量、密度和大气成分,有助于深入分析宜居性特征.此外,对ET新发现的大量各种系外行星样本的研究,以及对理论的检验将推动这些种类的行星形成和演化规律的更深入认识, ET的大量高精度、高频次和长基线测光数据将推动星震学、银河系考古学、时域天文学、双星和双星黑洞等领域的研究.

关键词：系外行星类地行星宜居带凌星微引力透镜测光

The microgravity enhanced polymer-mediated siRNA gene silence by improving cellular uptake

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Biophysics Reports 2020年第6期6卷 266-277页

作者： Tongren Yang Chanchan Yu Changrong Wang Chunhui Li Mengjie zhang Xiaofan Luo Yuhua Weng Anjie dong Xiaoqiong Li Yulin Deng Yuanyu Huang school of Life Science Advanced Research Institute of Multidisciplinary ScienceInstitute of Engineering MedicineKey Laboratory of Molecular Medicine and BiotherapyBeijing Institute of Technology Department of Polymer Science and Technology School of Chemical Engineering and TechnologyKey Laboratory of Systems Bioengineering of the Ministry of EducationTianjin University school of Pharmacy Hunan University of Chinese Medicine

Microgravity(MG) effect is a weightlessness phenomenon caused by the distance from the ground or low gravity of other planets outside the earth”s atmosphere. The various effects of MG have been corroborated in human and animal studies and modeled in cell-based analogs. However, the impact of MG on siRNA performance remains to be elucidated, which is crucial for aerospace medicine. In this study, we prepared nucleic acid nanomicelles(EAASc/siRNA) by using tri-block copolymer of PEG45-PAMA40-P(C7 A36-DBA37)(EAASc) and siRNA and explored its working mechanism under simulated microgravity(SMG) condition generated by a random positioning machine(RPM). The binding ability of EAASc to siRNA and silence activity were firstly confirmed in normal gravity(NG) *** of PLK1 mRNA expression revealed that gene inhibition efficiencies were increased by28.7%(HepG2) and 28.9%(A549) under SMG condition, compared with those under NG condition. In addition, mechanism exploration indicated that morphology and migration capability of cancer cells were significantly changed, the internalization of EAASc/siRNA by cells was magnified when the cells were incubated with RPM. No significant difference was observed regarding the expression profiles of genes involved in RNA interference(RNAi) pathway, including Ago2, Dicer, TRBP, and so on. Taken together, siRNA activity was elevated under SMG condition owning to increased cellular *** study, for the first time to our knowledge, provides valuable theory for development and application of siRNA therapeutic in space in the future.

关键词： Polymer siRNA PLK1 Microgravity space pharmaceutics Aerospace medicine

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麻粒岩的研究进展与方法

岩石学报 2021年第1期37卷 52-64页

作者：魏春景张媛媛董杰造山带与地壳演化教育部重点实验室北京大学地球与空间科学学院北京100871

近年来,有关麻粒岩的研究取得了长足进展,本文讨论了4个相关问题:(1)麻粒岩的大地构造环境与P-T轨迹。麻粒岩可以形成于4种大地构造环境中:(a)碰撞造山带以形成高压麻粒岩为特征,为中压相系,包括曾位于地壳浅部的岩石经历构造埋深达到... 详细信息

近年来,有关麻粒岩的研究取得了长足进展,本文讨论了4个相关问题:(1)麻粒岩的大地构造环境与P-T轨迹。麻粒岩可以形成于4种大地构造环境中:(a)碰撞造山带以形成高压麻粒岩为特征,为中压相系,包括曾位于地壳浅部的岩石经历构造埋深达到变质峰期后再折返的过程,为顺时针型P-T轨迹;也包括曾经历洋壳或陆壳俯冲形成的高压-超高压榴辉岩相岩石折返叠加变质形成的麻粒岩,P-T轨迹以减压为主。(b)地壳伸展区以形成低压麻粒岩为特征,并可达到超高温条件,其P-T轨迹为减压加热至温度峰期,随后发生等压或降压冷却。(c)岛弧或陆缘岩浆增生区的下地壳多为高压麻粒岩相,其中侵入的辉长岩首先经历等压冷却,然后再经历升温升压进变质过程。(d)太古宙克拉通麻粒岩相表壳岩呈皮筏状分布于TTG片麻岩内部,多达到超高温条件,发育逆时针型P-T轨迹,受太古宙特殊的垂直构造体制控制。(2)麻粒岩的进变质过程与流体行为。按照流体行为,麻粒岩的进变质过程分为3种型式:(a)流体饱和进变质过程,指岩石在饱水固相线之前达到流体饱和,随后发生饱水固相线熔融与含水矿物的脱水熔融,以及阶段性熔体丢失,导致岩石中水含量降低,缺流体固相线温度升高;在峰期之后的降温过程中,发生熔融反应的逆反应,或结晶反应,形成含水矿物,结晶反应终止于缺流体固相线。(b)流体不饱和或缺流体进变质过程,指岩石在进变质过程中会处于流体缺失状态,不会发生变质反应,岩石中原来的矿物组合以亚稳定状态保留至缺流体固相线后,才开始变质演化,因此经常形成一些不平衡结构。(c)流体过饱和进变质过程,指有过量水参与的熔融反应过程,也称为水化熔融,与熔体注入或局部汇聚有关;水化熔融过程中会更多地消耗斜长石、石英及辉石等无水矿物,导致残余物中富集角闪石和黑云母等含水矿物。(3)确定麻粒岩P-T条件的视剖面图方法。利用视剖面图方法分析麻粒岩的变质条件时,首先需要通过岩相学观察区分出峰期组合和最终组合;然后通过计算T-M(H2O)图解确定最终组合的含水量;最后利用所确定的水含量计算P-T视剖面图。利用P-T视剖面图分析麻粒岩的峰期变质条件时,首先找到峰期矿物组合在视剖面图上的稳定域,然后再结合有价值的矿物成分等值线确定P-T条件。特别需要注意的是,岩相学观察确定的峰期组合和最终组合都可能受局部结构域控制,与滞留熔体的不均匀分布或原地分凝有关,此时不能简单地用全岩成分模拟其相平衡关系。(4)相平衡模拟时需要选择有效的全岩成分。当选择实测全岩成分进行相平衡模拟时,首先需要检验其有效性,即检验实测全岩成分是否能够代表薄片中所观察到的相平衡关系。方法是计算有效全岩成分,并与实测全岩成分进行对比。对于成分不均匀的变质岩石,需要处理局部结构域的成分。分如下3种情况:(a)宏观尺度的结构域,可以分别取样;(b)微观尺度的结构域,需要在显微薄片中进行图像分析,针对不同结构域分别进行相平衡模拟;(c)由叠加或退变质形成的结构域,需要确定相应的变质反应,通过对反应配平,确定有效全岩成分。此外,文中还介绍了计算岩石中的水含量、O含量和各种矿物相含量的方法与注意事项。

关键词：麻粒岩大地构造环境 P-T轨迹相平衡模拟有效全岩成分

Multi-stage metallogeny in the southwestern part of South china,and paleotectonic and climatic implications:A high precision geochronologic study

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Geoscience Frontiers 2023年第3期14卷 131-147页

作者： Yanbin Liu Lifei zhang MSantosh Guochen dong Hongying Zhou Chaoyang Que Cheng-Xue Yang State Key Laboratory of Geological Processes and Mineral Resources and School of Earth Science and ResourcesChina University of GeosciencesBeijing 100083China MOE Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China Department of earth Science University of AdelaideAdelaide SA 5005Australia Tianjin Institute of Geology and Mineral Resources China Geological SurveyTianjin 300170China Zijin Mining Industry Groups Co. Ltd.Xiamen 361009FujianChina

The South china Block(SCB)is among the large-scale W-Sn mineralized regions of the *** Laojunshan W-Sn-dominant ore area(LOA)in the western part of the SCB preserves the records of the tectonic history of the Tethys realm extending through North Vietnam,and Yangtze to Cathaysia blocks,with coeval formation of giant metallic *** prolonged tectonic activities and their control on the genesis and spatio-temporal distribution of giant metallic deposits in the LOA provide a window for a holistic understanding of the tectono-metallogenesis of the *** this study,we present results from a multi-chronologic study to determine the timing of formation of the cassiterite-wolframite-schee lite *** results suggest three distinct tectono-metallogenic periods in the LOA during the geodynamic evolution of the surrounding tectonic *** opening of the Proto-Tethys Ocean between the Yangtze-Indochina blocks and the westward Paleo-Pacific subduction beneath the Cathaysia block(420–380 Ma)jointly contributed to the Silurian to early Devonian intracontinental orogeny in the middle of the SCB that involved top-to-the-north thrusting along NE-striking shear *** event generated the Dulong-Song Chay granitoids,together with the formation of Xinzhai Sn deposit related to sheared mylonitic granites(ca.419 Ma)and pegmatites(ca.389 Ma),which include the early-stage Sn-sulfide skarn(ca.418 Ma)and the late-stage Sn-bearing schist(ca.389 Ma).During the Late Permian to Late Triassic(260–220 Ma),with the closure of the Proto-Tethys oceans in the west and ongoing Paleo-Pacific westward subduction in the east,the SCB and Indochina Block(IB)were amalgamated which also marks the time of formation of the Nanwenhe scheelite skarn *** subducted PaleoTethys oceanic crust was likely entrained by the nearby rising Emeishan mantle plume(270–259 Ma),which formed the Maguan diabase(ca.260 Ma)that shows significantly older Re-Os model age of ca.268 Ma,suggesting

关键词： Sn-W mineralization Geochronology Tectonics setting South china Block Tethys realm