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Journal of Rare earths 2011年第2期29卷 185-192页

作者：孙林华桂和荣陈松 School of earth Sciences and Engineering Suzhou University

Rare earth element （REE） concentrations of two different types of groundwaters （high SO42–water-SW and high alkaline waterCW） from coal bearing aquifer （–400~–280 m） in Renlou coal mine,northern Anhui Province,China were *** results indicated that they had different REE characteristics： the total concentrations of REEs （ΣREE） of SW were lower than those of CW in general although they all had heavy REEs enriched relative to light *** dissolved REE inorganic species of SW included Ln3＋,LnCO3＋,LnSO4＋,Ln（CO3）2– and Ln（SO4）2–,whereas the CW are Ln（CO3）2– and LnCO3＋ dominant,and the proportions of Ln（CO3）2– increased while other species decreased with pH *** with correlation analysis,the enrichment and fractionation of SW （low alkaline water） were considered to be affected by alkaline concentrations via affecting the types and proportions of REE inorganic ***,the effect of alkaline concentrations to the enrichment and fractionation of REEs of CW （high alkaline water） was less important than total dissolved solids and pH,which reflected the contribution from different rocks they flowed over,different degrees of water-rock interactions and/or REE solid-liquid partition coefficients.

关键词： rare earth elements inorganic speciation enrichment and fractionation coal bearing aquifer groundwater

Preparing Process of Cerium Acetate and Rare earth Acetate

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Journal of Rare earths 2004年第Z1期22卷 26-31页

作者： Qiao Jun Ma Ying Xu Yanhui Zhang Jun Chang Shu Hao Xianku Baotou Research Institute of Rare earth Baotou 014010 China Baotou Research Institute of Rare Earth Baotou 014010 China Baotou Research Institute of Rare Earth Baotou 014010 China Baotou Research Institute of Rare Earth Baotou 014010 China Baotou Research Institute of Rare Earth Baotou 014010 China Baotou Research Institute of Rare Earth Baotou 014010 China

Preparing process was presented and the influences of concentration of acetic acid, reaction temperature, the ratio of cerium carbonate and acetic acid, heat preservation time to the yield of cerium acetate were *** crystalline cerium acetate and rare earth acetate such as ( La, Ce, Pr, Nd) (Ac) 3, ( Ce, Pr, Nd) (Ac) 3, ( Pr, Nd, Er,Y) (Ac) 3 and yttrium acetate were prepared under this *** shape, structure and composition of the crystals were determined by the methods of SEM, TG-DTA, X-ray diffraction and chemical *** optimum prepared conditions of cerium acetate were *** prepared process has characteristics such as simple process route, low cost, high yield, good quality, no pollution to environment, etc.

关键词： cerium acetate, rare earth acetate, composition rare earths

Observational evidences of wave excitation and inverse cascade in a distant earth foreshock region

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Science China earth Sciences 2019年第4期62卷 619-630页

作者： Jiansen HE Die DUAN Xingyu ZHU Limei YAN Linghua WANG School of earth and Space Sciences Peking University Key Laboratory of earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences

The foreshock with nascent plasma turbulence is regarded as a fascinating region to understand basic plasma physical processes, e.g., wave-particle interactions as well as wave-wave couplings. Although there have been plenty of intensive studies on this topic, some key clues about the physical processes still lack observations. A relatively comprehensive case study with some new observations is presented in this work based on the WIND spacecraft observations. In this case, upstream energetic protons were drifting at tens of Alfvén speed with respect to the background plasma protons. When looking at the magnetic wave activities, we find the co-existence of high-frequency(0.1-0.5 Hz) large-amplitude right-hand polarized(RHP) waves and lowfrequency(0.02-0.1 Hz) small-amplitude left-hand polarized(LHP) waves in the spacecraft(SC) frame. The observed anticorrelation between magnetic and velocity fluctuations along with the sunward magnetic field direction indicates that the lowfrequency LHP waves in the SC frame are in fact the sunward upstream RHP Alfvénic waves in the solar wind frame. This new observation corroborates the applicability of theories about plasma non-resonance instability and inverse cascade to the foreshock region, where the downstream high-frequency RHP parent waves are excited by the upstream energetic protons through non-resonance instability and the low-frequency RHP daughter waves are generated by the parent waves due to nonlinear parametric instability. Furthermore, enhanced downstream energetic proton fluxes are inferred to result from scattering of the upstream protons by the nascent turbulent fluctuations. Therefore, some critical clues about the newborn turbulence in the foreshock are provided in this work.

关键词： Solar wind Foreshock Wave-particle interaction Parametric instability

The thermal conductivity of the earth's core and implications for its thermal and compositional evolution

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National Science Review 2021年第4期8卷 18-20页

作者： Kenji Ohta Kei Hirose Department of earth and Planetary Sciences Tokyo Institute of Technology earth-Life Science Institute Tokyo Institute of Technology Department of earth and Planetary Science The University of Tokyo

The thermal conductivity of iron alloys is a key to understanding the mechanism of convection in the earth’s liquid core and its thermal history. The earth’s magnetic field is formed by a dynamo action that requires...

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A digital earth platform for sustainability

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International Journal of Digital earth 2017年第4期10卷 342-355页

作者： Mario Hernandez Engagement Committee Future EarthMexico CityMexico International Society for Digital earth Mexico CityMexico

Based on the experience of the International Society for Digital earth(ISDE),this paper describes some challenges foreseen in order to develop a Digital earth platform that can support the implementation of the Sustainable Development *** use of ready-to-use derived geospatial information is *** earth’s methodology of‘co-design’aims to bring together natural,social scientists and decision makers to plan and carry out research for *** implies transdisciplinary research,but in order for scientists of different disciplines to work together,they will need to be able to share,access and use common *** is by far not simple!While the good will to share data might exist,the associated technological,ethical and privacy issues are difficult to *** adequate e-infrastructure will be *** could consider to use the SDGs is the basis to develop the desired Digital earth *** paper,by no means,covers everything for a Digital earth platform,it aims to trigger research discussions and to have a good view about a starting point.

关键词： Digital earth platform sustainable development Sustainable Development Goals future earth

Rare earth element geochemistry of Post-to Neo-archean shales from Singhbhum mobile belt, Eastern India: implications for tectonic setting and paleo-oxidation conditions

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Chinese Journal Of Geochemistry 2015年第3期34卷 401-409页

作者： Akhtar R.Mir Department of earth Sciences University of Kashmir

In the present study, trace element(including rare earth element) chemical data has been interpreted with the aim to decipher the tectonic setting and paleo-redox conditions of the Post- to Neo-archean shales from the Singhbhum Mobile Belt, eastern India. The data show moderate enrichment of compatible elements [such as Cu(avg. 59.28 ppm), Ni(avg. 59.49 ppm), V(avg.234.24 ppm) and Cr(avg. 181.23 ppm)] relative to the Post-Archean Australian Shale. Their chondrite normalized light rare earth elements are moderately fractionated [(La/Sm)Nranges from 2.21 to 5.78], whereas heavy rare earth elements show a nearly flat pattern [(Gd/Lu)Nranges from0.74 to 1.68]; this indicates that the rare earth element(REE) concentrations, rather than being severely affected by the diagenesis and weathering processes, decreased gradually from Gd to Lu. The Post-Archean Australian Shale normalized multi-element diagram shows the slight enrichment of Cr, V, Zr, Y, U and Sc, whereas Sr, Pb, Hf and Th are depleted. The notable negative anomaly of Sr indicates the least accumulation of plagioclase, which is also supported by the negative Eu-anomaly in these *** La–Th–Sc and Th–Zr–Sc tectonic setting diagrams indicate their continental arc setting. The geochemical parameters, such as U/Th, V/Cr, Ni/Co, and Cu/Zn, indicate that these shales were deposited under oxic to anoxic environmental conditions.

关键词：稀土元素地球化学特征新太古代页岩印度构造意义氧化条件移动氧化还原条件

Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen Tang Sai Zhang FuLiang Xiao HongMing Yang Si Liu YiHua He Chang Yang YuYue Jin ZhouKun Deng Ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation (AKR) is a common radio emission,which can contribute to the magnetosphere-ionosphereatmosphere co u *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500-4500 km and invariant latitude (|ILAT|)=60°-80°has been analyzed.63045 AKR samples have been identified with~48%(52%) samples on the dayside (nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05-08 and 18-22(02-05 and 12-17) in the northern (southern) *** distinct MLT asymmetry is associated with the direction of Bxof the interplaneta ry magnetic *** addition,the occurrence rate on the nightside clearly increases as the AE^(*) index *** study further enriches the information and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field

Models of the earth's plasmapause position

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Science China earth Sciences 2016年第4期59卷 871-872页

作者： FU SuiYan SUN WeiJie School of earth and Space Sciences Peking University

The plasmasphere is a region of relatively dense （-10-10000 cm^-3） plasma, surrounding the earth and ex- tending to distances of about five earth radii （RE）. It is filled with large amount of cold （-1 eV） plasma originated from the earth＇s ionosphere and co-rotating with the earth due to the large scale co-rotation electric field. The outermost boundary of the plasmashere is called the plasmapause.

关键词：等离子体层地球半径模型位置旋转电场等离子体源电离层距离

Origin of the earth:A proposal of new model called ABEL

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Geoscience Frontiers 2017年第2期8卷 253-274页

作者： Shigenori Maruyama Toshikazu Ebisuzaki earth-Life Science Institute Tokyo Institute of Technology Institute for Study of the earth's Interior Okayama University RIKEN

The earth was born as a dry planet without atmosphere and ocean components at 4.56 Ga,with subsequent secondary accretion of bio-elements,such as carbon（C）,hydrogen（H）,oxygen（O）,and nitrogen（N） which peaked at 4.37-4.20 *** two-step formation model of the earth we refer to as the advent of bio-elements model（ABEL Model） and the event of the advent of bio-elements（water component） as ABEL *** is clear that the solid earth originated from enstatite chondrite-like dry material based on the similarity in oxygen isotopic composition and among other *** the other hand,earth＇s water derives primarily from carbonaceous chondrite material based on the hydrogen isotopic *** present our ABEL model to explain this enigma between solid earth and water,as well as secondary accretion of oxidizing bio-elements,which became a precursor to initiate metabolism to emerge life on a highly reductive *** ABEL Bombardment had not occurred,life never would have emerged on the ***,ABEL Bombardment is one of the most important events for this planet to evolve into a habitable *** chronology of ABEL Bombardment is informed through previous researches of the late heavy bombardment and the late veneer *** Bombardment is considered to have occurred during 4.37-4.20 Ga,which is the concept to redefine the standard late heavy bombardment and the late veneer ***,ABEL Bombardment is the trigger of the transition from stagnant lid tectonics to plate tectonics on this planet because of the injection of volatiles into the initial dry earth.

关键词： Origin of earth and life Advent of bin-elements (ABEL)Origin of water on the earth ABEL Bombardment Habitable Trinity planet Initiation of plate tectonics

Late Ordovician Mass Extinction: earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.T.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

The Late Ordovician Mass Extinction was the earliest of the ‘big' five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas