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Multi-spherical interactions and mechanisms of hydrocarbon enrichment in the Southeast Asian archipelagic tectonic system 被引量:4
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作者 Rixiang ZHU Hongjun WANG +9 位作者 Huajian WANG Xiaomei WANG Bo WAN Wang ZHANG Houqin ZHU Yuke LIU Junlai LIU Qingren MENG Fang HAO Zhijun JIN 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第2期566-583,共18页
Global cooling began since 50 Ma,but a warm climate was maintained in the archipelagic tectonic system in Southeast Asia where a wealth of Cenozoic oil and gas resources was formed and preserved.From the perspective o... Global cooling began since 50 Ma,but a warm climate was maintained in the archipelagic tectonic system in Southeast Asia where a wealth of Cenozoic oil and gas resources was formed and preserved.From the perspective of Earth system,this study analyzes Cenozoic tectonic activities,climatic and environmental evolution,and petroleum enrichment in Southeast Asia,and provides the following insights:(1)Subduction of oceanic plates and the extension of overlying continental lithosphere resulted in widespread volcanic eruptions as well as the formation of rift basins and shallow marine shelves,leading to complex interactions between deep tectonic processes and Earth’s surface including mountains,basins,and seas.(2)Microcontinental accretion and prolonged stay in equatorial low-latitude regions have changed trade winds into monsoons,altered ocean current pathways and flow rates,and profoundly affected rainfall and climate.(3)The archipelagic tectonic system,coupled with a hot and rainy climate,fostered tropical rainforests,mangroves,and phytoplankton,providing abundant organic matter and promoting the development of petroleum resources.(4)Combinations of rift basin development and marine transgression and regression led to an effective superposition of source-reservoir-seal combinations from multiplepetroleum systems.Rapid deep burial of organic matter and high geothermal gradients facilitated the generation and large-scale accumulation of oil and gas.(5)Multi-spherical(such as atmosphere,biosphere,hydrosphere and lithosphere)interactions on the Earth,which resulted from the convergence of multiple tectonic plates,are believed as the primary driver for exceptional enrichments of Cenozoic oil and gas resources in Southeast Asia.These understandings are significant for developing theories of oil and gas enrichment under the guidance of Earth System Science.In order to continue making significant oil and gas exploration discoveries in the deep-layers,deep-waters,and unconventional oil and gas fields of Southeast Asia,attention should be paid to the oil and gas resource effects of the collision between Australia and Sunda blocks and the high-temperature and high-rainfall climate environment,and efforts should be made to develop economic development and CO_(2)sequestration technologies for offshore CO_(2)-rich gas fields. 展开更多
关键词 southeast Asia Archipelagic tectonic system interactions of earth’s spheres Oil and gas resources CENOZOIC
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Tracking a maneuvering target in clutter with out-of-sequence measurements for airborne radar 被引量:3
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作者 Weihua Wu Jing Jiang Yang Wan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第4期746-753,共8页
There are many proposed optimal or suboptimal al- gorithms to update out-of-sequence measurement(s) (OoSM(s)) for linear-Gaussian systems, but few algorithms are dedicated to track a maneuvering target in clutte... There are many proposed optimal or suboptimal al- gorithms to update out-of-sequence measurement(s) (OoSM(s)) for linear-Gaussian systems, but few algorithms are dedicated to track a maneuvering target in clutter by using OoSMs. In order to address the nonlinear OoSMs obtained by the airborne radar located on a moving platform from a maneuvering target in clut- ter, an interacting multiple model probabilistic data association (IMMPDA) algorithm with the OoSM is developed. To be practical, the algorithm is based on the Earth-centered Earth-fixed (ECEF) coordinate system where it considers the effect of the platform's attitude and the curvature of the Earth. The proposed method is validated through the Monte Carlo test compared with the perfor- mance of the standard IMMPDA algorithm ignoring the OoSM, and the conclusions show that using the OoSM can improve the track- ing performance, and the shorter the lag step is, the greater degree the performance is improved, but when the lag step is large, the performance is not improved any more by using the OoSM, which can provide some references for engineering application. 展开更多
关键词 out-of-sequence measurement(s (OosM(s)) earth-centered earth-fixed (ECEF) interacting multiple model (IMM) probabilistic data association (PDA) attitude.
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Influence of Ga^(3+) on Photoluminescence of Ce^(3+)
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作者 徐春祥 娄志东 +1 位作者 刘行仁 徐叙瑢 《Journal of Rare Earths》 SCIE EI CAS CSCD 1998年第2期16-20,共5页
The electro optical characteristics of SrS∶Ce and SrGa 2S 4∶Ce as two kinds of hopeful blue TFEL phosphors have been intensively investigated. The color purity of SrGa 2S 4∶Ce is better than that of SrS∶Ce. ... The electro optical characteristics of SrS∶Ce and SrGa 2S 4∶Ce as two kinds of hopeful blue TFEL phosphors have been intensively investigated. The color purity of SrGa 2S 4∶Ce is better than that of SrS∶Ce. In this paper, the influence of Ga 3+ on photoluminescence (PL) characteristics of Ce 3+ is first reported. Ga 2S 3 was doped into SrS, then sintered. The emission spectra shift obviously towards short wavelength range with increase of Ga 3+ concentration. At the same time, the relative intensity of the excitation peaks corresponding to the interband absorption of SrS reduces, and the excitation efficiency corresponding to the transition from the ground state to the excited state of Ce 3+ ion increases. The ligand field around Ce 3+ is changed by doped Ga 3+ . The ionicity of the substituted become stronger and Ce 3+ -Ce 3+ interaction become weaker. These are favorite to blue emission. 展开更多
关键词 Rare earths srGa 2s 4∶Ce Blue shift Excitation efficiency Ligand field Ce 3%PLUs% -Ce 3%PLUs% interaction
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An Axion Interpretation of the ANITA Events
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作者 A. Nicolaidis 《Journal of Modern Physics》 2021年第2期59-64,共6页
We suggest that the unusual events observed by the ANITA experiment originate from axion particles traversing the Earth. Under the influence of the geomagnetic field, the axion may oscillate into a photon and vice-ver... We suggest that the unusual events observed by the ANITA experiment originate from axion particles traversing the Earth. Under the influence of the geomagnetic field, the axion may oscillate into a photon and vice-versa. To amplify the axion transition into photon, we consider that the phenomenon takes place at resonance, where the effective photon mass is equal to the axion mass. This requirement fixes the axion mass at 44 eV. An axion at this mass scale reproduces the cold dark matter scenario. If our interpretation prevails, with the help of axions we can establish an axion tomography of the Earth. 展开更多
关键词 AXION Axion-Photon interaction earth’s Magnetic Field COsMOLOGY Dark Matter Multimessenger Astronomy
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Global Bioethical Prevention of the Collision of Biological and Cultural Evolution on Miserable Human Survival
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作者 lames E. Trosko 《Sociology Study》 2015年第4期295-313,共19页
With the cultural myth that science can only determine the way the world "is" (facts), while humanities, social sciences, lawyers, philosophers, and theologians must determine the way the world "ought to be" (v... With the cultural myth that science can only determine the way the world "is" (facts), while humanities, social sciences, lawyers, philosophers, and theologians must determine the way the world "ought to be" (values), those in position of global-, national-, and local-political power make major decisions of the use (or non-use) of scientific knowledge and technology. As a result, the human being has created a non-scientifically based cultural environment that is affecting his ability to survive. In effect, cultural evolution is occurring more rapidly than biological evolution that can adapt to the changes brought about in the physical and psycho-social environments. In a pluralistic cultural world, where each society has generated a different view of human nature and different ethical values, the use, misuse, or non-use of scientific and technological advances are derived from these unscientific views of human nature. Since all life depends on limiting interacting environmental and ecological factors, it is imperative that scientific information be used to govern how to minimize irreversible effects on life-sustaining ecological factors, but also scientific information bearing on understanding human nature ought to be integrated into a "global bioethics". While ethical values cannot be directly derived from scientific factors, it is also true that human values or our "ought" cannot be maintained in ignorance or defiance of the facts or the "is". 展开更多
关键词 Global bioethics scientific concepts of human nature genetic and environmental interactions one health-one planet humanimpact on earths ecosystem
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Mesoporous CeO_(2)-C hybrid spheres as efficient support for platinum nanoparticles towards methanol electrocatalytic oxidation 被引量:2
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作者 Weili Li Qi Wang +2 位作者 Lei Wang Xian-Zhu Fu Jing-Li Luo 《Journal of Rare Earths》 SCIE EI CAS CSCD 2021年第6期674-681,I0003,共9页
The development of direct methanol fuel cells(DMFCs) is partially limited by the poor kinetics of methanol oxidation reaction(MOR) at the anode side.It was reported that the interaction between Pt and CeO_(2) enhances... The development of direct methanol fuel cells(DMFCs) is partially limited by the poor kinetics of methanol oxidation reaction(MOR) at the anode side.It was reported that the interaction between Pt and CeO_(2) enhances the electrocatalytic performance of Pt catalyst for MOR.In this work,a hybrid material(CeO_(2)-C) composed of CeO_(2) and carbon was successfully prepared by a simple hydrothermal method followed by calcination in inert atmosphere.The hierarchically porous nanostructure and especially good electronic conductivity of CeO_(2)-C make it an excellent support for Pt particles for application in electrocatalytic process.TEM investigation reveals that triple-phase interface of Pt,carbon and CeO_(2) forms in Pt/CeO_(2)-C catalyst.Performance of the as-prepared catalyst for MOR was studied in alkaline medium.The Pt/CeO_(2)-C catalyst shows superior catalytic performance for MOR compared with Pt/CeO_(2) and the physical mixture of Pt/CeO_(2) and acetylene black(Pt/CeO_(2)+C).The significantly improved performance can be attributed to the synergetic effect between Pt particles and CeO_(2)-C support,and the better conductivity of CeO_(2)-C.This study provides a possible method to expand the application potential of CeO_(2) materials in MOR,and may also be used in other electrocatalytic process. 展开更多
关键词 Pt based catalyst Mesoporous CeO_(2)-C spheres Metal-support interaction Methanol oxidation Rare earths
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松辽盆地中生代地质事件节律及圈层耦合 被引量:10
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作者 黄福堂 黄清华 陈春瑞 《石油勘探与开发》 SCIE EI CAS CSCD 北大核心 1998年第5期86-89,共4页
根据近年来多学科研究新成果,讨论松辽盆地中生代岩石圈、水圈、大气圈和生物圈事件。岩石圈事件包括9次规模不等的构造变动和9次强弱不同的火山喷发活动;水圈事件包括3次显著的古湖泊缺氧事件和3套红色碎屑岩充填事件;大气圈事... 根据近年来多学科研究新成果,讨论松辽盆地中生代岩石圈、水圈、大气圈和生物圈事件。岩石圈事件包括9次规模不等的构造变动和9次强弱不同的火山喷发活动;水圈事件包括3次显著的古湖泊缺氧事件和3套红色碎屑岩充填事件;大气圈事件包括3次显著的升温、降温和干湿度变化事件;生物圈事件包括热河动物群、松花江生物群、明水生物群的突发演化和更替事件。这些地质事件是地球各圈层发展、演化的重要里程碑。上述事件的重要特征是在时间上的节律性和在成因上的圈层耦合效应。图1参13(梁大新摘) 展开更多
关键词 中生代 圈层耦合 油气形成 盆地
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大气海洋油气质点受力分析 被引量:10
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作者 刘全稳 陈景山 沈守文 《成都理工学院学报》 CSCD 2000年第3期268-275,共8页
从平面入手 ,讨论了地球球面质点在绕太阳运行过程中的受力情况 ,并推得球面质点所受各力的表达式 ,讨论了各力的函数关系及其变化性质 ,对有关各力进行比较归类 ,指出了各力的适应性及存在问题。展望了各力在大气、海洋、油气、板块等... 从平面入手 ,讨论了地球球面质点在绕太阳运行过程中的受力情况 ,并推得球面质点所受各力的表达式 ,讨论了各力的函数关系及其变化性质 ,对有关各力进行比较归类 ,指出了各力的适应性及存在问题。展望了各力在大气、海洋、油气、板块等运动研究方面的应用前景。 展开更多
关键词 质点 受力分析 地球 太阳 大气 海洋 油气运移
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大陆构造、大洋构造和地球构造研究构想 被引量:8
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作者 马宗晋 高祥林 《地学前缘》 EI CAS CSCD 2004年第3期9-14,共6页
大陆动力学和大洋动力学是当前固体地球科学的前沿领域 ,反映处于中期阶段的板块理论正向更加深入、全面、完善的方向发展 ,并走向统一的地球构造学的趋势。中、新生代造山带构造 ,全球高原构造的比较 ,周边洋底构造对欧亚大陆的动力作... 大陆动力学和大洋动力学是当前固体地球科学的前沿领域 ,反映处于中期阶段的板块理论正向更加深入、全面、完善的方向发展 ,并走向统一的地球构造学的趋势。中、新生代造山带构造 ,全球高原构造的比较 ,周边洋底构造对欧亚大陆的动力作用 ,应是大陆动力学中优先研究的问题。对全球洋底构造的继续探测 ,用地震各向异性研究地幔的流动或变形 ,布设海底宽频带地震台阵探测地幔细结构 ,将会提供更多的地球内部过程信息。“地球大系统科学”概念的提出 ,将能推进固、液、气三态地球多球层相互作用的研究 ,例如固体地球微动态、固液气三态球层运动的可比较性、不同球层分区性的比较等 ,都是需要深入探讨的问题 。 展开更多
关键词 大陆构造 大洋构造 多球层相互作用 地球系统科学
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地球圈层相互作用中的深海过程和深海记录(I):研究进展与成果 被引量:3
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作者 汪品先 翦知湣 刘志飞 《地球科学进展》 CAS CSCD 北大核心 2006年第4期331-337,共7页
由五大系统11个实验室组成的项目组,2000—2005年开展了以“地球圈层相互作用”为主题的深海基础研究。项目以“热带碳循环”作为核心问题,依靠国际大洋钻探和国内“大洋专项”两大支柱,对西太平洋暖池和南海等海区进行深海过程和深海... 由五大系统11个实验室组成的项目组,2000—2005年开展了以“地球圈层相互作用”为主题的深海基础研究。项目以“热带碳循环”作为核心问题,依靠国际大洋钻探和国内“大洋专项”两大支柱,对西太平洋暖池和南海等海区进行深海过程和深海记录的研究,已圆满完成计划任务。一方面在南海大洋钻探的基础上,围绕热带海洋在地球系统中的作用向纵深发展,在“热带碳循环”研究中取得了原创性的成果;另一方面依托国内大洋专项和国内外合作航次,在深海研究和圈层相互作用上朝横向发展,取得了一系列国际性成果,在我国形成了与国际接轨的深海研究力量。对该项目的设计和进展做了简单而又全面的阐述,对于古环境研究中取得的突破性进展将另有续篇介绍。 展开更多
关键词 深海研究 地球系统 圈层相互作用
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重大地史事件、节律及圈层耦合 被引量:7
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作者 龚一鸣 《地学前缘》 EI CAS CSCD 1997年第3期75-84,共10页
文章讨论了岩石圈的联合古陆事件,生物圈的重要生物类别的出现、生物爆发事件和集群绝灭事件,水圈和大气圈的海平面变化事件和气候的变冷、变暖事件。联合古陆事件包括陆核型联合古陆(2500Ma)、初始原地台型联合古陆(190... 文章讨论了岩石圈的联合古陆事件,生物圈的重要生物类别的出现、生物爆发事件和集群绝灭事件,水圈和大气圈的海平面变化事件和气候的变冷、变暖事件。联合古陆事件包括陆核型联合古陆(2500Ma)、初始原地台型联合古陆(1900Ma)、成熟原地台型联合古陆(1450Ma)、地台型联合古陆(850Ma)和大陆型联合古陆(250Ma)事件;生物圈事件包括原核生物、真核生物、后生动物、带壳后生动物的出现事件,寒武纪生物大爆发事件,奥陶纪—志留纪之交(439Ma)、晚泥盆世弗拉斯期—法门期之交(367Ma)、二叠纪—三叠纪之交(250Ma)、三叠纪—侏罗纪之交(208Ma)、白垩纪—第三纪之交(65Ma)的生物集群绝灭事件,并从遗迹化石的角度,阐述了后生动物及其行为习性的起源和演化的新观点。水圈和大气圈事件包括晚震旦世、奥陶纪—志留纪之交、晚石炭世的自节律海平面变化事件,奥陶纪和白垩纪的他节律高海平面事件,震旦纪—寒武纪和二叠纪—三叠纪之交的耦合节律海平面变化事件,并以泥盆纪为例作了进一步阐述。这些事件是岩石圈、生物圈、水圈和大气圈发展、演化的重要里程碑。上述事件的重要特征是,在时间上的节律性和在成因上的圈层耦合效应。 展开更多
关键词 地史事件 节律 圈层耦合 岩石圈 水圈 大气圈
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青藏高原南部和北部暖季气温年代际变化差异的界线位置 被引量:28
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作者 王宁练 《第四纪研究》 CAS CSCD 北大核心 2006年第2期165-172,共8页
文章通过对青藏高原北部马兰冰芯中δ^18O记录(主要反映暖季气温)与近几十年来高原中、南部气象台站暖季气温变化的对比分析,发现在年代际时间尺度上高原北部地区暖季气温变化与南部地区存在明显的差异,其分界线位于32°~33... 文章通过对青藏高原北部马兰冰芯中δ^18O记录(主要反映暖季气温)与近几十年来高原中、南部气象台站暖季气温变化的对比分析,发现在年代际时间尺度上高原北部地区暖季气温变化与南部地区存在明显的差异,其分界线位于32°~33°N附近一带。该位置也是青藏高原地区气候、地理、地质、地球物理等方面存在南北差异的重要分界线。 展开更多
关键词 青藏高原 马兰冰芯 气候变化 圈层相互作用
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采用桩土共同作用的浙江省第一医院医技楼现场实测分析 被引量:7
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作者 张忠苗 张乾青 李建华 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2010年第4期833-841,共9页
采用桩土共同作用设计方法的浙江省第一医院医技楼实测资料表明,大楼装修完成时基础底板周边和内部实测平均土压力分别已达地基土承载力特征值的83.3%和62.7%,地基土承载力被较大程度的得到利用。桩顶应变计实测结果显示,大楼竣工时桩... 采用桩土共同作用设计方法的浙江省第一医院医技楼实测资料表明,大楼装修完成时基础底板周边和内部实测平均土压力分别已达地基土承载力特征值的83.3%和62.7%,地基土承载力被较大程度的得到利用。桩顶应变计实测结果显示,大楼竣工时桩顶反力超过单桩极限承载力的50%,这是与传统设计方法的不同之处。同时,随建筑层数的增加,桩间土分担荷载的比例逐渐减少,装修完成时土承担上部荷载的20%。而在大楼结顶时基础底板内钢筋实测应力很小,基础底板面层和底层钢筋平均压应力分别为9.84和7.68MPa,远低于钢筋所能承受的最大抗压值。同时发现,基础底板的存在会削弱桩侧摩阻力,相同桩顶荷载水平下全桩长范围内实测桩基平均侧摩阻力均小于静载试验中单桩的平均侧摩阻力。该大楼实测沉降结果表明,沉降较小且较为均匀,能满足使用要求。 展开更多
关键词 桩基工程 桩土共同作用 土压力 桩顶反力 钢筋应力 侧摩阻力 沉降
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初论构造应力-应变系统的复杂性 被引量:3
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作者 万天丰 《地学前缘》 EI CAS CSCD 2000年第1期161-168,共8页
地球内部构造应力主要集中于岩石圈上层。通过岩石变形的微观机制与宏观表现的研究 ,可以看出 :构造应力应变作用绝不仅仅是一种简单的、线性的力学过程 ,而是多圈层相互作用、受多种物理和化学因素控制的、非线性作用过程。地球构造应... 地球内部构造应力主要集中于岩石圈上层。通过岩石变形的微观机制与宏观表现的研究 ,可以看出 :构造应力应变作用绝不仅仅是一种简单的、线性的力学过程 ,而是多圈层相互作用、受多种物理和化学因素控制的、非线性作用过程。地球构造应力场在不可逆演化过程中是一种具有某种阵发式变化的复杂系统。 展开更多
关键词 构造应力 应变系统 复杂性 变形机制 岩石圈
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核幔相互作用与地球发电机理论
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作者 马石庄 魏青云 徐文耀 《地球科学进展》 CAS CSCD 1992年第2期31-34,共4页
扼要地阐述了地球发电机理论在地球深部研究中的重要地位;强调地球磁场及其时空变化是认识地球深部,尤其是核幔相互作用的主要途径;提出当前推进地球发电机理论研究的一个突破口是揭示核幔相互作用,特别是热的和化学的相互作用对地球发... 扼要地阐述了地球发电机理论在地球深部研究中的重要地位;强调地球磁场及其时空变化是认识地球深部,尤其是核幔相互作用的主要途径;提出当前推进地球发电机理论研究的一个突破口是揭示核幔相互作用,特别是热的和化学的相互作用对地球发电机模型的影响。 展开更多
关键词 核幔相互作用 地球发电机 地球深部
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Artificial modification of Earth's radiation belts by ground-based very-low-frequency(VLF)transmitters 被引量:5
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作者 Binbin NI Man HUA +4 位作者 Xudong GU Song FU Zheng XIANG Xing CAO Xin MA 《Science China Earth Sciences》 SCIE EI CSCD 2022年第3期391-413,共23页
Wave-particle interactions play a fundamental role in the dynamic variability of Earth’s donut-shaped radiation belts that are highly populated by magnetically trapped energetic particles and characteristically separ... Wave-particle interactions play a fundamental role in the dynamic variability of Earth’s donut-shaped radiation belts that are highly populated by magnetically trapped energetic particles and characteristically separated by the slot devoid of high energetic electrons.Owing to the continuous accumulation of high-quality wave and particle measurements from multiple satellites in geospace,the important contribution of ground-based very-low-frequency(VLF)transmitter waves to the electron dynamics in the near-Earth space has been unprecedently advanced,in addition to those established findings of the significant effects of a variety of naturally occurring magnetospheric waves.This paper focuses on the artificial modification of Earth’s inner radiation belt and slot by artificial VLF transmitter emissions.We review the global distributions of VLF transmitter waves in geospace,their scattering effects on radiation belt electrons in terms of both theoretical and observational analyses,and diffusion simulation results of wave-particle interactions along with data-model comparisons.We start with a brief review of the radiation belt electron dynamics and an introduction of anthropogenic VLF transmitter waves.Subsequently,we review the global morphology of in situ VLF transmitter waves corresponding to different transmitter locations,including their day-night asymmetry,geographic distributions,seasonal and geomagnetic activity dependence,and wave propagation features.Existed theoretical and observational analyses of electron scattering effects by VLF transmitter waves are then reviewed to approach the underlying physics that can modulate the spatio-temporal variations of the electron radiation belts.Further Fokker-Planck electron diffusion simulations and their comparisons with realistic satellite observations clearly indicate that VLF transmitter emissions can effectively remove energetic electrons to produce a radially bifurcated electron belt,thereby quantitatively confirming the direct link between operations of VLF transmitters at ground and changes of the energetic electron environment in space.We finally discuss the unsolved problems and possible future research in this area,which has important implications for potential mitigation of the natural particle radiation environment with active means. 展开更多
关键词 VLF transmitters Wave-particle interactions Electron precipitation earth’s radiation belts Flux bifurcation
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CONSTANT VOLUMES PER OXYGEN OF THE EARTH'S LAYERS 被引量:1
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作者 叶大年 张金民 《Science China Chemistry》 SCIE EI CAS 1990年第7期887-896,共10页
Through the calculation of the VPOs (volume per oxygen) of 1698 rocks and minerals, the authors reach the following conclusion: the mean VPO of glassy extrusive rocks is 22.5. The mean VPO of semicrystalline extrusive... Through the calculation of the VPOs (volume per oxygen) of 1698 rocks and minerals, the authors reach the following conclusion: the mean VPO of glassy extrusive rocks is 22.5. The mean VPO of semicrystalline extrusive rocks is 21.5. Crystalline extrusive and all intrusive rooks from granite to gabbro have a mean VPO of 20.6. According to the models of the earth’s layers, the VPO of the upper crust is 20.8. If the lower crust is composed of gabbro, the VPO is about the same as that of the upper crust. If it consists of amphibolite or dioritic garnet granulite, the VPO is 18.8. Based on the data of mantle inclusions and high pressure and high temperature experiments, the calculated VPO of the upper mantle is 17.7. All these are constants in each layer and correspond to the packing concentrations in the packing of equal spheres. 展开更多
关键词 earth’s LAYERs volume PER OXYGEN PACKING of equal spheres
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Effects of the precursor size on the morphologies and properties of γ-Ce_2S_3 as a pigment 被引量:9
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作者 于世泳 王东日 +1 位作者 高小龙 苏海全 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第6期540-544,共5页
Ceria spheres with different sizes and sulfurized products with corresponding morphology were prepared by hydro-thermal and gas-solid reaction method at 600-800℃ under CS2 atmosphere for a short time, respectively. D... Ceria spheres with different sizes and sulfurized products with corresponding morphology were prepared by hydro-thermal and gas-solid reaction method at 600-800℃ under CS2 atmosphere for a short time, respectively. Dimensional effect in preparation ofγ-Ce2S3 was firstly investigated by means of techniques such as scanning electron microscopy (SEM), X-ray dif-fraction (XRD), thermal gravimetric analysis (TGA) and spectrophotometer. The results showed that when ceria nanoparticles with small size were used as precursors, theγ-Ce2S3 could be prepared at the lower temperature and the badly sintered products were obtained; when ceria nanoparticles with large size were employed as precursors, pureγ-Ce2S3 was difficultly obtained even if the temperature was up to 800℃ and the products tended to keep their original size. The heat-resistance property of theγ-Ce2S3 with large size was better than the smaller one, and the pureγ-Ce2S3 prepared from precursor with small size had a good pigmen-tary performance. 展开更多
关键词 ceria sphere sIZE γ-Ce2s3 low temperature pigmentary performance rare earths
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地球宜居性的深部驱动机制 被引量:4
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作者 徐义刚 黄小龙 +6 位作者 王强 王煜 李高军 刘耘 毛河光 倪怀玮 朱茂炎 《科学通报》 EI CAS CSCD 北大核心 2024年第2期169-183,共15页
除与太阳之间的距离和行星的大小有关外,地球之所以宜居的一个重要因素是其拥有动力十足的地球内部.与地球宜居性是地球表生作用结果的传统认识不同,本文认为地球深部驱动着对宜居环境至关重要的外部层圈,并提出地球内外层圈间的联动机... 除与太阳之间的距离和行星的大小有关外,地球之所以宜居的一个重要因素是其拥有动力十足的地球内部.与地球宜居性是地球表生作用结果的传统认识不同,本文认为地球深部驱动着对宜居环境至关重要的外部层圈,并提出地球内外层圈间的联动机制是地球系统科学研究的突破口.在调研和评述的基础上,本文建议未来研究需要关注早期地球、地磁场、深地挥发分循环、超级火山、深地新化学反应和地质空调器等方向,围绕地球宜居性的深部驱动机制这一主题,开展地球固体层圈与流体层圈的整合研究,助力我国地球科学研究从单一学科研究向多学科交叉融合研究的转变,推动我国固体地球科学从跟踪前沿向开拓前沿的跨越式发展. 展开更多
关键词 地球宜居性 深部引擎 深地过程 层圈相互作用 地球系统科学
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新生代特提斯海峡关闭过程及其圈层耦合效应 被引量:1
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作者 孙继敏 沙金庚 王世骐 《科学通报》 EI CAS CSCD 北大核心 2024年第2期184-199,共16页
新生代是地球历史上岩石圈、水圈、大气圈、生物圈发生宏观巨变的重要地质时期,包括了冈瓦纳大陆的快速裂解、海峡的开启与闭合、海洋与大气环流的重组、温室到冰室的气候转型以及动植物的快速演替,因而是开展圈层耦合研究的关键地质时... 新生代是地球历史上岩石圈、水圈、大气圈、生物圈发生宏观巨变的重要地质时期,包括了冈瓦纳大陆的快速裂解、海峡的开启与闭合、海洋与大气环流的重组、温室到冰室的气候转型以及动植物的快速演替,因而是开展圈层耦合研究的关键地质时期.本文以特提斯海峡为例,从地球系统科学角度,阐述特提斯海峡的闭合过程、时间及其对生物圈、海洋环流、大气圈的链式影响和反馈.核心思想如下:特提斯海峡自渐新世至中-中新世晚期(34∼12.8 Ma)历经了阶段性的演化过程,渐新世时期的特提斯海峡很好地连通了低纬度的印度洋-古地中海-大西洋;早中新世时(21∼19 Ma),伴随着非洲-阿拉伯板块与欧亚大陆的汇聚,海峡的连通能力下降了90%;中-中新世气候适宜期(17∼15 Ma)以海岸潟湖相为主、夹浅海相环境;15∼12.8 Ma期间演化为陆相环境为主、夹短暂的周期性海侵,且具有10万年的准周期;12.8 Ma之后,海峡永久关闭.特提斯海峡的闭合过程对生物圈产生了显著影响,伴随海峡的逐渐闭合,海洋无脊椎动物的腹足类、棘皮类,逐渐从特提斯海向印度洋、西太平洋迁移.对哺乳动物而言,尽管早中新世已经有零星的哺乳动物在非洲-阿拉伯与欧亚大陆之间迁徙,但真正大规模的哺乳动物双向迁徙主要发生在18∼17 Ma之后.此时,以海岸潟湖相为主的海峡已不足以构成善于利用迁徙路径的哺乳动物的地理屏障,表现为非洲的灵长类、长鼻类、蹄兔类等向欧亚大陆迁徙.而欧亚大陆的食肉类、犀类、猪类、反刍类、啮齿类等向非洲-阿拉伯迁徙.特提斯海峡的关闭对海洋环流也有重要影响,主要表现为特提斯海峡的关闭减少了来自低纬的温暖、高盐海水向大西洋及印度洋南部的注入,由此降低了低纬的热量向南半球高纬的径向输送,在一定程度上加强了东南极冰盖的扩张及南极的变冷.特提斯海的退缩以及特提斯海峡在13 Ma左右的永久关闭,也深刻影响到南亚季风环流,表现为索马里急流和南亚季风的加强. 展开更多
关键词 阿拉伯与欧亚大陆汇聚 特提斯海峡闭合 海陆分布 地球圈层相互作用 环境效应
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