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地球宜居性的深部驱动机制

科学通报 2024年第2期69卷 169-183页

作者：徐义刚黄小龙王强王煜李高军刘耘毛河光倪怀玮朱茂炎中国科学院广州地球化学研究所同位素地球化学国家重点实验室广州510640 南京大学地球科学与工程学院南京210023 中国科学院地球化学研究所矿床地球化学国家重点实验室贵阳550081 北京高压科学研究中心北京100094 中国科学技术大学中国科学院壳幔物质与环境重点实验室合肥230026 中国科学院南京地质古生物研究所现代古生物和地层学国家重点实验室南京210080

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... 详细信息

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.

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

Development of High-Pressure Multigrain X-Ray Diffraction for Exploring the Earth’s Interior

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Engineering 2019年第3期5卷 441-447页

作者： Li Zhang hongsheng Yuan Yue Meng ho-kwang mao Center for High Pressure Science and Technology Advanced Research (HPSTAR) Shanghai 201203 China HPCAT X-Ray Science Division Argonne National Laboratory Argonne IL 60439 USA Geophysical Laboratory Carnegie Institution of Washington Washington DC 20015 USA

The lower mantle makes up more than a half of our planet’s volume. Mineralogical and petrological experiments on realistic bulk compositions under high pressure–temperature (P–T) conditions are essential for understanding deep mantle processes. Such high P–T experiments are commonly conducted in a laser-heated diamond anvil cell, producing a multiphase assemblage consisting of 100 nm to submicron crystallite grains. The structures of these lower mantle phases often cannot be preserved upon pressure quenching;thus, in situ characterization is needed. The X-ray diffraction (XRD) pattern of such a multiphase assemblage usually displays a mixture of diffraction spots and rings as a result of the coarse grain size relative to the small X-ray beam size (3–5 lm) available at the synchrotron facilities. Severe peak overlapping from multiple phases renders the powder XRD method inadequate for indexing new phases and minor phases. Consequently, structure determination of new phases in a high P–T multiphase assemblage has been extremely difficult using conventional XRD techniques. Our recent development of multigrain XRD in high-pressure research has enabled the indexation of hundreds of individual crystallite grains simultaneously through the determination of crystallographic orientations for these individual grains. Once indexation is achieved, each grain can be treated as a single crystal. The combined crystallographic information from individual grains can be used to determine the crystal structures of new phases and minor phases simultaneously in a multiphase system. With this new development, we have opened up a new area of crystallography under the high P–T conditions of the deep lower mantle. This paper explains key challenges in studying multiphase systems and demonstrates the unique capabilities of high-pressure multigrain XRD through successful examples of its applications.

关键词： High pressure Synchrotron X-ray Multigrain Diamond anvil cell Minerals Petrology Earth’s interior

Triggering dynamics of acetylene topochemical polymerization

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Matter and Radiation at Extremes 2023年第5期8卷 82-88页

作者： Xingyu Tang Xiao Dong Chunfang Zhang Kuo Li Haiyan Zheng ho-kwang mao Center for High Pressure Science and Technology Advanced Research Beijing 100193People’s Republic of China Key Laboratory of Weak-Light Nonlinear Photonics School of PhysicsNankai UniversityTianjin 300071People’s Republic of China College of Chemistry and Materials Science Hebei UniversityBaoding 071002People’s Republic of China

Topochemical reactions are a promising method to obtain crystalline polymeric materials with distance-determined regio-or *** has been concluded on an empirical basis that the closest intermolecular C⋅⋅⋅C distance in crystals of alkynes,d(C⋅⋅⋅C)min,should reach a threshold of∼3Åfor bonding to occur at room *** understand this empirical threshold,we study here the polymerization of acetylene in the crystalline state under high pressure by calculating the structural geometry,vibrational modes,and reaction *** find d(C⋅⋅⋅C)min to be the sum of an intrinsic threshold of 2.3Åand a thermal displacement of 0.8Å(at room temperature).Molecules at the empirical threshold move via several phonon modes to reach the intrinsic threshold,at which the intermolecular electronic interaction is sharply enhanced and bonding commences.A distance–vibration-based reaction picture is thus demonstrated,which provides a basis for the prediction and design of topochemical reactions,as well as an enhanced understanding of the bonding process in solids.

关键词： temperature bonding polymerization

The near-room-temperature upsurge of electrical resistivity in Lu-H-N is not superconductivity,but a metal-to-poor-conductor transition

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Matter and Radiation at Extremes 2023年第5期8卷 96-98页

作者： Di Peng Qiaoshi Zeng Fujun Lan Zhenfang Xing Yang Ding ho-kwang mao Center for High Pressure Science and Technology Advanced Research Shanghai 201203China Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Shanghai Key Laboratory of Material Frontiers Research in Extreme Environments(MFree) Shanghai Advanced Research in Physical Sciences(SHARPS)Shanghai 201203China State Key Laboratory of Superhard Materials Institute of PhysicsJilin UniversityChangchun 130012China

The recent report of superconductivity in nitrogen-doped lutetium hydride(Lu-H-N)at 294 K and 1 GPa brought hope for long-sought-after ambient-condition ***,the failure of scientists worldwide to independently reproduce these results has cast intense skepticism on this exciting *** this work,using a reliable experimental protocol,we synthesized Lu-H-N while minimizing extrinsic influences and reproduced the sudden change in resistance near room *** quantitative comparison of the temperaturedependent resistance between Lu-H-N and the pure lutetium before reaction,we were able to clarify that the drastic resistance change is most likely caused by a metal-to-poor-conductor transition rather than by ***,we also briefly discuss other issues recently raised in relation to the Lu-H-N system.

关键词： resistance superconductivity transition

Chemical transformations of n-hexane and cyclohexane under the upper mantle conditions

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Geoscience Frontiers 2021年第2期12卷 1010-1017页

作者： Xin Yang Yapei Li Yajie Wang Haiyan Zheng Kuo Li ho-kwang mao Center for High Pressure Science and Technology Advanced Research Beijing100094China

Alkanes are an important part of petroleum,the stability of alkanes under extreme conditions is of great significance to explore the origin of petroleum and the carbon cycle in the deep ***,we performed Raman and infrared(IR)spectroscopy studies of n-hexane and cyclohexane under high pressure up to~42 GPa at room temperature(RT)and high temperature(HT).n-Hexane and cyclohexane undergo several phase transitions at RT around 1.8,8.5,18 GPa and 1.1,2.1,4.6,13,30 GPa,respectively,without any chemical *** using resistive heating combined with diamond anvil cell at pressure up to 20 GPa and temperature up to 1000 K,both n-hexane and cyclohexane decompose to hydrogenated graphitic carbon and n-hexane exhibits higher stability than *** results indicate that hydrocarbons tend to dehydrogenate in the upper mantle,and the extension of carbon chains may lead to the formation of some unsaturated compounds and eventually transfer into graphitic products.

关键词： Alkanes High pressure and high temperature Dehydrogenation Hydrocarbon Upper mantle conditions

Mineralogy of the deep lower mantle in the presence of H2O

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National Science Review 2021年第4期8卷 21-28页

作者： Qingyang Hu Jin Liu Jiuhua Chen Bingmin Yan Yue Meng Vitali B.Prakapenka Wendy L.mao ho-kwang mao Center for High Pressure Science and Technology Advanced Research(HPSTAR) Department of Geological Sciences Stanford University Center for Study of Matter under Extreme Conditions Department of Mechanical and Materials Engineering Florida International University High Pressure Collaborative Access Team(HPCAT) X-ray Science Division Argonne National Laboratory Center for Advanced Radiation Sources University of Chicago

Understanding the mineralogy of the Earth's interior is a prerequisite for unravelling the evolution and dynamics of our planet. Here, we conducted high pressure-temperature experiments mimicking the conditions of the deep lower mantle（DLM, 1800–2890 km in depth） and observed surprising mineralogical transformations in the presence of water. Ferropericlase,（Mg,Fe）O, which is the most abundant oxide mineral in Earth, reacts with H;2;O to form a previously unknown（Mg,Fe）O;2;H;x;（x ≤ 1）phase. The（Mg,Fe）O;2;H;x;has a pyrite structure and it coexists with the dominant silicate phases,bridgmanite and post-perovskite. Depending on Mg content and geotherm temperatures, the transformation may occur at 1800 km for(Mg;0.6;Fe;0.4;)O or beyond 2300 km for(Mg;0.7;Fe;0.3;)O. The（Mg,Fe）O;2;H;x;is an oxygen excess phase that stores an excessive amount of oxygen beyond the charge balance of maximum cation valences(Mg;2+;, Fe;3+;and H;+;). This important phase has a number of far-reaching implications including extreme redox inhomogeneity, deep-oxygen reservoirs in the DLM and an internal source for modulating oxygen in the atmosphere.

关键词： lower mantle water-mantle interaction ferropericlase high pressure mantle mineralogy

Evolution of Superconducting-Transition Temperature with Superfluid Density and Conductivity in Pressurized Cuprate Superconductors

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Chinese Physics Letters 2024年第4期41卷 110-117页

作者：赵金瑜蔡树陈逸雯顾根大闫宏涛郭静韩金宇王鹏玉周亚洲李延春李晓东任治安吴奇周兴江丁阳向涛毛河光孙力玲 Institute of Physics Chinese Academy of SciencesBeijing 100190China Center for High Pressure Science&Technology Advanced Research Beijing 100094China Condensed Matter Physics&Materials Science Department Brookhaven National LaboratoryNY 11973-5000USA University of Chinese Academy of Sciences Beijing 100190China Institute of High Energy Physics Chinese Academy of ScienceBeijing 100049China Beijing Academy of Quantum Information Sciences Beijing 100193China

What factors fundamentally determine the value of superconducting transition temperature Tc in high temperature superconductors has been the subject of intense *** the establishment of an empirical law known as homes'law,there is a growing consensus in the community that the Tc value of the cuprate superconductors is closely linked to the superfluid density(ρ_(s))of its ground state and the conductivity(σ)of its normal ***,all the data supporting this empirical law(ρ_(s)=AσT_(c))have been obtained from the ambientpressure *** this study,we present the first high-pressure results about the connection of the quantities of ρ_(s) and σ with T_(c),through the studies on the Bi_(1.74)Pb_(0.38)Sr_(1.88)CuO_(6+δ)and Bi_(2)Sr_(2)CaCu_(2)O_(8+δ),in which the value of their high-pressure resistivity(ρ=1/σ)is achieved by adopting our newly established method,while the quantity ofρs is extracted using homes'*** highlight that the Tc values are strongly linked to the joint response factors of magnetic field and electric field,i.e.,ρ_(s) and σ,respectively,implying that the physics determining T_(c) is governed by the intrinsic electromagnetic fields of the system.

关键词： superconductors Transition Conductivity

Stabilization of S_(3)O_(4) at high pressure:implications for the sulfur-excess paradox

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Science Bulletin 2022年第9期67卷 971-976,M0004页

作者： Siyu Liu Pengyue Gao Andreas Hermann Guochun Yang Jian Lu Yanming Ma ho-kwang mao Yanchao Wang These authors contributed equally to this work.a State Key Laboratory ofSuperhard Materials&International Center of Computational Method and Software College of PhysicsJilin UniversityChangchun 130012China Centre for Science at Extreme Conditions and Scottish Universities Physics Alliance School of Physics and AstronomyThe University of EdinburghEdinburgh EH93FDUK State Key Laboratory of Metastable Materials Science&Technology and Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China International Center of Future Science Jilin UniversityChangchun 130012China Center for High Pressure Science and Technology Advanced Research Beijing 100094China

The amount of sulfur in SO2 discharged in volcanic eruptions exceeds that available for degassing from the erupted *** geological conun drum,known as the"sulfur excess",has been the subject of considerable interests but remains an open ***,in a systematic computational investigation of sulfur-oxygen compounds under pressure,a hitherto unknown S_(3)O_(4) compound containing a mixture of sulfur oxidation states+11 and+IV is predicted to be stable at pressures above 79 *** speculate that S_(3)O_(4) may be produced via redox reactions involving subducted S-bearing minerals(e.g.,sulfates and sulfides)with iron and goethite under high-pressure conditions of the deep lower mantle,decomposing to SO2 and S at shallow depths.S_(3)O_(4) may thus be a key intermediate in promoting decomposition of sulfates to release SO2,offering an alter native source of excess sulfur released during explosive *** findings provide a possible resolution of the"excess sulfur degassing"paradox and a viable mechanism for the exchange of S between Earth's surface and the lower mantle in the deep sulfur cycle.

关键词： Crystal structure prediction High-pressure chemistry S-bearing minerals Sulfur cycle Excess sulfur

Evidence for oxygenation of Fe-Mg oxides at mid-mantle conditions and the rise of deep oxygen

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National Science Review 2021年第4期8卷 29-34页

作者： Jin Liu Chenxu Wang Chaojia Lv Xiaowan Su Yijin Liu Ruilian Tang Jiuhua Chen Qingyang Hu ho-kwang mao Wendy L.mao Center for High Pressure Science and Technology Advanced Research (HPSTAR) Department of Geological Sciences Stanford University School of Earth and Space Sciences Peking University SLAC National Accelerator Laboratory Center for Study of Matter at Extreme Conditions Department of Mechanical and Materials Engineering Florida International University

As the reaction product of subducted water and the iron core, FeO2with more oxygen than hematite(Fe2O3) has been recently recognized as an important component in the D" layer just above the Earth’s core-mantle boundary. Here, we report a new oxygen-excess phase(Mg, Fe)2O3+δ(0 holds excess oxygen through interactions between oxygen atoms. The new OE-phase provides strong evidence that H2O has extraordinary oxidation power at high pressure. Unlike the formation of pyrite-type FeO2Hxwhich usually requires saturated water, the OE-phase can be formed with under-saturated water at mid-mantle conditions, and is expected to be more ubiquitous at depths greater than 1000 km in the Earth’s mantle. The emergence of oxygen-excess reservoirs out of primordial or subducted(Mg,Fe)-bearing hydrous materials may revise our view on the deep-mantle redox chemistry.

关键词： subducting slab hydrous phase lower mantle deep oxygen oxygen-excess oxides