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Plasma Science and Technology 2019年第5期21卷 93-101页

作者： Quanming LU Huayue CHEN Yangguang KE Shui WANG CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary ScienceUniversity of Science and Technology of ChinaHefei 230026People's Republic of China National centre for Physics(NCP)at Quaid-e-Azam University Campus Shahdra Valley Road.Islamabad 44000Pakistan Hefei National Laboratory for Physical Sciences at the Microscale and Department of Physics University of Science and Technology of ChinaHefei 230026People's Republic of China

By performing one-dimensional particle-in-cell simulations, the nonlinear effects of electronacoustic(EA) waves are investigated in a multispecies plasma, whose constituents are hot electrons, cold electrons, and beam electrons with immobile neutralized positive ions. Numerical analyses have identified that EA waves with a sufficiently large amplitude tend to trap cold electrons. Because EA waves are dispersive, where the wave modes with different wavenumbers have different phase velocities, the trapping may lead to the mixing of cold electrons. The cold electrons finally get thermalized or heated. The investigation also shows that the excited EA waves give rise to a broad range of wave frequencies, which may be helpful for understanding the broadband-electrostatic-noise spectrum in the Earth’s auroral region.

关键词： electron acoustic waves cold electrons trapping particle-in-cell(PIC)simulation

Genesis of the Bianjiadayuan Pb-Zn polymetallic deposit, Inner Mongolia, China:Constraints from in-situ sulfur isotope and trace element geochemistry of pyrite

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Geoscience Frontiers 2019年第5期10卷 1863-1877页

作者： Kai-Rui Song Li Tang Shou-Ting Zhang M. Santosh Christopher J. Spencer Yu Zhao Hao-Xing Li Liang Wang An-Li Zhang Yin-Qiang Sun School of the Earth Sciences and Resources China University of Geosciences (Beijing)Beijing 100083China centre for Tectonics Exploration and ResearchUniversity of AdelaideAdelaideSA5005Australia School of Earth and planetary Sciences The Institute of Geoscience ResearchCurtin UniversityPerthWA6845Australia Lituo Mining Company Chifeng 024000China 243 Team China Nuclear GeologyChifeng 024000China

The Southern Great Xing’an Range (SGXR) which forms part of the eastern segment of the Central Asian Orogenic Belt (CAOB) is known as one of the most important Cu-Mo-Pb-Zn-Ag-Au metallogenic belts in China,hosting a number of porphyry Mo (Cu),skarn Fe (Sn),epithermal Au-Ag,and hydrothermal veintype Ag-Pb-Zn ore *** we investigate the Bianjiadayuan hydrothermal vein-type Ag-Pb-Zn ore deposit in the southern part of the *** Sn ±Cu ± Mo mineralization is also developed to the west of the Ag-Pb-Zn veins in the ore *** identify a five-stage mineralization process based on field and petrologic studies including (i) the early porphyry mineralization stage,(ii) main porphyry mineralization stage,(iii) transition mineralization stage,(iv) vein-type mineralization stage and (v) late mineralization *** is the predominant sulfide mineral in all stages except in the late mineralization stage,and we identify corresponding four types of pyrites: Py1 is medium-grained subhedral to euhedral occurring in the early barren quartz vein;Py2 is medium- to fine-grained euhedral pyrite mainly coexisting with molybdenite,chalcopyrite,minor sphalerite and galena;Py3 is fine-grained,subhedral to irregular pyrite and displays cataclastic textures with micro-fractures;Py4 occurs as euhedral microcrystals and forms irregularly shaped aggregate with sphalerite and ***-ICP-MS trace element analyses of pyrite show that Cu,Pb,Zn,Ag,Sn,Cd and Sb are partitioned into pyrite as structurally bound metals or mineral micro/nano-inclusions,whereas Co,Ni,As and Se enter the lattice via isomorphism in all types of *** Cu,Zn,Ag,Cd concentrations gradually increase from Py1 to Py4,which we correlate with cooling and mixing of ore-forming fluid with meteoric ***2 contains the highest contents of Co,Ni,Se,Te and Bi,suggesting high temperature conditions for the porphyry mineralization *** of Co/Ni (0.03-10.79,average 2.13) and sulphur isotope compositio

关键词： Trace elements In-situ sulfur isotope Pyrite Bianjiadayuan deposit Southern Great Xing'an range

Precipitation of High Mg-Calcite and Protodolomite Using Dead Biomass of Aerobic Halophilic Bacteria

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Journal of Earth Science 2023年第2期34卷 456-466页

作者： Qigao Fan Deng Liu Dominic Papineau Xuan Qiu Hongmei Wang Zhenbing She Linduo Zhao State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430078China School of Environmental studies China University of GeosciencesWuhan 430078China London centre for Nanotechnology University College London and Birkbeck College LondonLondon 17-19UK Department of Earth Sciences University College LondonLondon WC1E 6BTUK Center for planetary Sciences University College LondonLondon WC1E 6BTUK Illinois Sustainable Technology Center Prairie Research InstituteUniversity of Illinois at Urbana-ChampaignChampaign 61820USA

The microbial dolomite model has been used to interpret the origin of sedimentary *** this model,the formation of low-temperature protodolomite,an important precursor to sedimentary dolomite,can be facilitated either by actively metabolizing cells of anaerobic microbes and aerobic halophilic archaea or by their inactive *** halophilic bacteria are widely distributed in(proto-)dolomite-depositing evaporitic environments and their biomass might serve as a template for the crystallization of *** test this hypothesis,carbonation experiments were conducted using dead biomass of an aerobic halophilic bacterium(Exiguobacterium *** JBHLT-3).Our results show that dead biomass of JBHLT-3 can accelerate Mg2+uptake in carbonate mineral *** addition,the amount of Mg incorporated into Ca-Mg carbonates is proportional to the concentration of *** Mg-calcite is produced with 0.25 or 0.5 g/L biomass,whereas protodolomite forms with 1 g/L *** is confirmed by the main Raman peak of Ca-Mg carbonates,which shifts towards higher wavenumbers with increased Mg *** cells and their imprints are preserved on the surface of high Mg-calcite and ***,this study furthers our understanding of the dolomitization within buried and dead microbial mats,which provides useful insights into the origin of ancient dolomite.

关键词： protodolomite high Mg-calcite Mg-hydration effect microbial dead biomass biosignature paleobiology

A Criterion for Tsunami Hazard Assessment at the Local Scale

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Journal of Geodesy and Geomatics Engineering 2015年第2期2卷 87-96页

作者： Angela Santos Shunichi Koshimura centre for Geographical studies Institute of Geography and Spatial Planning Universidade de Lisboa Edificio da Faculdade deLetras Alameda da Universidade Lisboa 1600-214 Portugal Laboratory of Remote Sensing and geoinformatics for Disaster Management International Research Institute of Disaster ScienceTohoku University Aoba 6-6-03 Aramaki Aoba-ku Sendai 980-8579 Japan

A criterion for tsunami hazard assessment at the local scale is proposed. It is based on travel times and water level height, calculated by the tsunami numerical model, combined with the existence or not of an easy evacuation path from the shoreline to safely high ground and evaluated by field survey. Furthermore, the 1755 Lisbon Tsunami is considered as the worst case scenario, allowing evaluating the impact of a similar scenario at Figueira da Foz municipality, Portugal. The results show that all the beaches are inundated and should be evacuated within an hour after the earthquake. Since there is safely high ground nearby most areas leading to a local tsunami hazard of＂low＂. However, the presence of unstable sand dunes that has been showing signs of collapsing at the south of Cova and Leirosa allowing the tsunami to penetrate inland, inundating the residential areas. For that reason, the local tsunami hazard is ＂moderate＂. The other area which has ＂moderate＂ classification is Cabedelo, because it does not have any coastal protection from tsunami waves, and does not have easy access to the high ground. The marina and fishing port have ＂very low＂ classification, nevertheless it is recommended that vessels evacuate to art offshore area.

关键词： Tsunami hazard tsunami numerical model field survey evacuation path 1755 Lisbon Tsunami.

Microbially-mediated formation of Ca-Fe carbonates during dissimilatory ferrihydrite reduction:Implications for the origin of sedimentary ankerite

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Science China Earth Sciences 2024年第1期67卷 208-221页

作者： Deng LIU Jinpeng CAO Shanshan YANG Yating YIN Pengcong WANG Dominic PAPINEAU Hongmei WANG Xuan QIU Genming LUO Zongmin ZHU Fengping WANG State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China School of Environmental studies China University of GeosciencesWuhan 430074China London centre for Nanotechnology University College LondonLondon WC1H 0AHUK Department of Earth Sciences University College LondonLondon WC1E 6BTUK Center for planetary Sciences University College London and Birkbeck College LondonLondon WC1E 6BTUK State Key Laboratory of Microbial Metabolism State Key Laboratory of Ocean EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The origin of sedimentary dolomite has become a long-standing problem in the Earth *** carbonate minerals like ankerite have the same crystal structure as dolomite,hence their genesis may provide clues to help solving the dolomite *** purpose of this study was to probe whether microbial activity can be involved in the formation of ***-carbonation experiments associated with microbial iron reduction were performed in batch systems with various concentrations of Ca^(2+)(0–20 mmol/L),with a marine iron-reducing bacterium Shewanella piezotolerans WP3 as the reaction mediator,and with lactate and ferrihydrite as the respective electron donor and *** biomineralization data showed that Ca-amendments expedited microbially-mediated ferrihydrite reduction by enhancing the adhesion between WP3 cells and ferrihydrite *** bioreduction,siderite occurred as the principal secondary mineral in the Ca-free ***,Ca-Fe carbonates were formed when Ca^(2+)ions were *** CaCO_(3) content of microbially-induced Ca-Fe carbonates was positively correlated with the initial Ca2+*** Ca-Fe carbonate phase produced in the 20 mmol/L Ca-amended biosystems had a chemical formula of Ca_(0.8)Fe_(1.2)(CO_(3))_(2),which is close to the theoretical composition of *** ankeritelike phase was nanometric in size and spherical,Ca-Fe disordered,and structurally *** simulated diagenesis experiments further demonstrated that the resulting ankerite-like phase could be converted into ordered ankerite under hydrothermal *** introduced the term“proto-ankerite”to define the Ca-Fe phases that possess near-ankerite stoichiometry but disordered cation *** the basis of the present study,we proposed herein that microbial activity is an important contributor to the genesis of sedimentary ankerite by providing the metastable Ca-Fe carbonate precursors.

关键词： Ankerite Proto-ankerite Microbial iron reduction Dolomite problem Mineral transformation

EFFECT OF INITIAL PERTURBATION OF LAND SURFACE PROCESSES ON TROPICAL CYCLONE FORECAST

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Journal of Tropical Meteorology 2012年第4期18卷 412-421页

作者：邓国周玉淑钟霖浩朱跃建理查德.沃巴斯魏谟政 National Meteorological centre Institute of Atmospheric Sciences Chinese Academy of Sciences NCEP Environmental Modelling centre

Many studies have explored the importance and influence of planetary boundary layer processes on tropical cyclones (TCs). However, few studies have focused on the influence of land surface processes on the activity of TCs. To test the effect of initial perturbations of land surface processes on TCs, a land surface process perturbation module is built in a global ensemble prediction system. Ensemble experiments for the TCs that occurred from 12 UTC 22 August to 18 UTC 24 November, 2006 show that consideration of the uncertainties within the land surface process could increase the predictability of the global ensemble prediction system. Detailed analysis on TC Xangsane (2006) indicates that the perturbation of land surface processes may increase the variation of sensible heat flux and latent heat flux. Meanwhile, the effect from land surface perturbation can be transferred to the upper atmosphere, which leads to better TC forecasts.

关键词： tropical cyclone land surface process initial perturbation ensemble prediction

Geoscience material structures prediction via CALYPSO methodology

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Chinese Physics B 2019年第10期28卷 38-49页

作者： Andreas Hermann centre for Science at Extreme Conditions and SUPA School of Physics and Astronomy The University of Edinburgh

Many properties of planets such as their interior structure and thermal evolution depend on the high-pressure properties of their constituent materials. This paper reviews how crystal structure prediction methodology can help shed light on the transformations materials undergo at the extreme conditions inside planets. The discussion focuses on three areas:(i) the propensity of iron to form compounds with volatile elements at planetary core conditions(important to understand the chemical makeup of Earth's inner core),(ii) the chemistry of mixtures of planetary ices(relevant for the mantle regions of giant icy planets), and(iii) examples of mantle minerals. In all cases the abilities and current limitations of crystal structure prediction are discussed across a range of example studies.

关键词： crystal structure prediction core materials planetary ices hydrous minerals

The Historical Review of the 1755 Lisbon Tsunami

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Journal of Geodesy and Geomatics Engineering 2015年第1期2卷 38-52页

作者： Angela Santos Shunichi Koshimura centre for Geographical studies Institute of Geography and Spatial Planning Universidade de Lisboa Edificio da Faculdade de Letras Alameda da Universidade Lisboa 1600-214 Portugal Laboratory of Remote Sensing and geoinformatics for Disaster Management International Research Institute of Disaster Science Tohoku University Aoba 6-6-03 Aramaki Aoba-ku Sendai 980-8579 Japan

The original accounts reporting the 1755 Lisbon Tsunami were compiled, focusing on the descriptions related to the tsunami parameters, damage and fatalities in the affected regions （Atlantic Northeast and Caribbean）. The accounts show the tsunami reached the southwest municipalities of Portugal in less than 30 minutes after the earthquake, and about one hour later the entire coasts of Portugal, Gulf of Cadiz （Spain） and Morocco were hit by the first tsunami waves. The tsunami took about five hours to reach Ireland and UK, and hit the Caribbean region about 9-10 hours after the earthquake. In addition, significant damage and fatalities were reported in Portugal （Peniche, the Lisbon Metropolitan Area and seven coastal areas in the south）, Spain （Cadiz） and in all Morocco coastline, including Marrakech which is located about 200 km inland. In Ireland, UK and the Caribbean minor damage was observed, and no fatalities were reported.

关键词： The 1755 Lisbon Tsunami historical accounts tsunami parameters fatalities damage.

Consumption Based Source Apportionment Indicates Different Regional Contributions to O3 Concentrations and Health Effects

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Engineering 2023年第9期28卷 130-138页

作者： Shengqiang Zhu Peng Wang Siyu Wang Guannan Geng Hongyan Zhao Yuan Wang Hongliang Zhang Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China Department of Atmospheric and Oceanic Sciences Fudan UniversityShanghai 200433China Integrated Research on Disaster Risk International centre of Excellence(IRDR ICoE)on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health Fudan UniversityShanghai 200433China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Center for Atmospheric Environmental studies School of EnvironmentBeijing Normal UniversityBeijing 100875China Division of Geological and planetary Sciences California Institute of TechnologyPasadenaCA 91020USA Institute of Eco-Chongming(IEC) East China Normal UniversityShanghai 200241China

China is confronting aggravated ozone(O_(3))pollution,leading to adverse health *** study quantifies the regional contributions to O_(3)in China using two approaches;estimating(1)where goods are produced(the production method),and(2)where goods are consumed(the consumption method).The production method predicts higher local source contribution than the consumption method;this difference can be attributed to *** of high-O_(3)episodes suggests a major contribution to O_(3)concentration as a result of trade *** on the consumption method,9219 out of 18532 daily premature mortalities were caused by local sources in north China,while it increased to 14471 of the production method when neglecting contributions due to export and consumption in other *** study suggests that O_(3)control should consider both where goods are consumed and emissions are emitted,especially taking account of international trade activities.

关键词： O_(3)pollution Trade Source-oriented CMAQ Health risks

Iron and Manganese in Groundwater of Rrogozhina Aquifer, Western Albania

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Journal of Environmental Science and Engineering(B) 2016年第6期5卷 276-285页

作者： Suada Luzati Arjan Beqiraj Enkeleida Beqiraj Goga Olgert Jaupaj Department of G1S Centre of Agricultural Technology Transfer Fushe Kruje 1502 Albania Department of Earth Sciences Faculty of Geology and Mining Str. "Elbasani "-Tirana 1021 Albania Dpartment of geoinformatics Albanian Geological Survey Str "Myslym Keta" Tirana 1045 Albania

This paper aims to advance previous studies on the iron and manganese content in groundwater of Rrogozhina aquifer （western Albania） and to show the factors which control the content of both iron and manganese in groundwater of this aquifer. Rrogozhina aquifer represents an important groundwater source of the country whose relevance was highly increased during recent years because of the demographic expansion in this region. This is a typically multi-layered artesian aquifer which consists of sandstone and conglomerate with high heterogeneous permeability. The groundwater mostly belongs to HCO3-Mg-Ca hydrochemical type. The content of soluble iron and manganese in groundwater ranges from 0.004 mg/L to 0.7 mg/L, and from 0.0 mg/L to 1.147 mg/L, respectively. Deeper the groundwater occurs and longer the distance from the recharge zone, higher is the content of Fe2＋ in groundwater due to gradual depletion of Oe in groundwater. The content of iron is higher than that WHO and EU recommended, which were 21% and 25% respectively, while the content of manganese were 17% and 23%, respectively. Abstraction of groundwater with high quantities by deeper wells would be accompanied by increase of dissolved iron and manganese content in groundwater which should be treated （with aeration） in order to decrease the content of these two elements in the water before using it.

关键词： Generalized Rrogozhina iron manganese aquifer groundwater.