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Three-dimensional Modeling of Ore-forming Elements and Mineralization Prognosis for the Yechangping Mo Deposit,Henan Province,China
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作者 DING Gaoming JI Genyuan +5 位作者 YAN Guolong XU Yongzhong WANG Kunming XIAO Chun WANG Quanle GUO Dongbao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期736-752,共17页
Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-di... Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-dimensional fine interpolation,analysis of spatial distribution patterns,and extraction of quantitative mineral-seeking markers.The Yechangping molybdenum(Mo)deposit is a significant and extensive porphyry-skarn deposit in the East Qinling-Dabie Mo polymetallic metallogenic belt at the southern margin of the North China Block.Abundant borehole data on oreforming elements underpin deep geochemical predictions.The methodology includes the following steps:(1)Threedimensional geological modeling of the deposit was established.(2)Correlation,cluster,and factor analyses post delineation of mineralization stages and determination of mineral generation sequence to identify(Cu,Pb,Zn,Ag)and(Mo,W,mfe)assemblages.(3)A three-dimensional geochemical block model was constructed for Mo,W,mfe,Cu,Zn,Pb,and Ag using the ordinary kriging method,and the variational function was developed.(4)Spatial distribution and enrichment characteristics analysis of ore-forming elements are performed to extract geological information,employing the variogram and w(Cu+Pb+Zn+Ag)/w(Mo+W)as predictive indicators.(5)Identifying the western,northwestern,and southwestern areas of the mine with limited mineralization potential,contrasted by the northeastern and southeastern areas favorable for mineral exploration. 展开更多
关键词 3D geochemical model ore-forming elements GEOSTATISTICS deep mineralization prediction Yechangping Mo deposit
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Effect of K Fertilizer on Absorption of Mineral Elements in Greenhouse-grown Strawberry Fruits
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作者 Dehua CHEN 《Plant Diseases and Pests》 2024年第2期32-33,共2页
[Objectives]The paper was to explore the effect of K fertilizer on the absorption of mineral elements in greenhouse-grown strawberry fruits.[Methods]A systematic investigation was conducted on the effects of K fertili... [Objectives]The paper was to explore the effect of K fertilizer on the absorption of mineral elements in greenhouse-grown strawberry fruits.[Methods]A systematic investigation was conducted on the effects of K fertilizer dosage levels on the absorption of mineral elements in Fengxiang strawberries,an excellent variety suitable for cultivation in Anhui Province.The investigation was carried out under medium N and P conditions in a greenhouse.[Results]The N content of strawberry fruits increased as the K_(2)O dosage increased within the range of 0-250 kg/hm^(2).Similarly,the P content of strawberry fruits increased gradually with the increase of K_(2)O dosage within the range of 0-125 kg/hm^(2).[Conclusions]This study presents a basis for enhancing the absorption of mineral elements in strawberry fruit by applying K appropriately. 展开更多
关键词 K fertilizer STRAWBERRY Mineral element
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Toward understanding the role of genomic repeat elements in neurodegenerative diseases
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作者 Zhengyu An Aidi Jiang Jingqi Chen 《Neural Regeneration Research》 SCIE CAS 2025年第3期646-659,共14页
Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage se... Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements. 展开更多
关键词 Alzheimer's disease ATAXIA deep learning long-read sequencing NEURODEGENERATION neurodegenerative diseases Parkinson's disease repeat element structural variant
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Landscape Planning and Design of Folk Culture Block Based on Theory of Three Elements of Landscape
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作者 吴忠军 胡林波 梁莉清 《Journal of Landscape Research》 2010年第9期24-28,共5页
This paper firstly defined the concept of folk culture block,and then analyzed the significance and planning principle of landscape design in folk culture block,and at last expounded landscape planning and design of f... This paper firstly defined the concept of folk culture block,and then analyzed the significance and planning principle of landscape design in folk culture block,and at last expounded landscape planning and design of folk culture block based on theory of three elements of landscape. 展开更多
关键词 THEORY of THree elements of LANDSCAPE FOLK culture BLOCK LANDSCAPE planning and design
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Computing of the Anchor by the Method of Three-Dimension Point-Radiate Infinite Elements 被引量:8
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作者 王艳芬 王元汉 谢洪阳 《Journal of China University of Geosciences》 SCIE CSCD 2007年第2期185-190,共6页
On the basis of the one-dimension infinite element theory, the coordinate translation and shape function of 3D point-radiate 8-node and 4-node infinite elements are derived. They are coupled with 20-node and 8-node fi... On the basis of the one-dimension infinite element theory, the coordinate translation and shape function of 3D point-radiate 8-node and 4-node infinite elements are derived. They are coupled with 20-node and 8-node finite elements to compute the compression distortion of the prestressed anchorage segment. The results indicate that when the prestressed force acts on the anchorage head and segment, the stresses and the displacements in the rock around the anchorage head and segment concentrate on the zone center with the anchor axis, and they decrease with exponential forms. Therefore,the stresses and the displacement spindles are formed. The calculating results of the infinite element are close to the theoretical results. This indicates the method is right. This article introduces a new way to study the mechanism of prestressed anchors. The obtained results have an important role in the research of the anchor mechanism and engineering application. 展开更多
关键词 infinite element prestressed anchor COUPLE finite element
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Behaviours of REE and Other Trace Elements During Pedological Weathering-Evidence from Chemical Leaching of Loess and Palaeosol from the Luochuan Section in Central China 被引量:4
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作者 Chen Jun, Wan Hongtao, Department of Earth Sciences, Nanjing University, Nanjing, Jiangsuand Lu HuayuKey Lab. of Loess and Quaternary Geology, Chinese Academy of Sciences,Xi an, Shaanxi Liu Xinzhu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1996年第3期290-302,共13页
The chemical leaching method is used for a systematic analysis of distribution characteristics of acid-soluble and acid-insoluble REE and other trace elements from the Luochuan loess deposits. The study shows that the... The chemical leaching method is used for a systematic analysis of distribution characteristics of acid-soluble and acid-insoluble REE and other trace elements from the Luochuan loess deposits. The study shows that the acid-insoluble phase in loess and palaeosol is a stable component of old aeolian dusts and is characteristic of the provenance; the acid-soluble phase is the unstable component in the weathering pedogenic process and reflects rock-forming features after accumulation of aeolian dusts. The acid-insoluble REE and acid-soluble Sr and Pb can be used as geochemical indicators respectively to trace the provenance characteristics and the weathering pedogenic process. 展开更多
关键词 chemical leaching loess and palaeosol ree geochemistry provenance characteristics weathering pedogenesis
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Geochemical Behaviors of REE and Other Trace Elements during the Formation of Strata-bound Skarns and Related Deposits:A Case Study of the Dongguashan Cu(Au)Deposit,Anhui Province,China 被引量:1
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作者 LINGQicong LIUCongqiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第2期246-257,共12页
REE and other trace elements in the altered marbles, massive skarns and ores, as well as garnet and quartz were determined in order to examine the behaviors of trace elements during hydrothermal alteration. It is demo... REE and other trace elements in the altered marbles, massive skarns and ores, as well as garnet and quartz were determined in order to examine the behaviors of trace elements during hydrothermal alteration. It is demonstrated that the high-field-strength (HFS) elements Zr, Hf, Th and Nb were immobile while other trace elements were mobile during the formation of skarns and related deposits. REE and ore-forming elements such as Cu and Ag in hydrothermally-altered marbles and skarns were provided primarily by hydrothermal fluids. In the direction transverse of the strata, the more deeply the marbles were altered, the higher the total REE abundance and the larger the negative Eu anomalies would be. The chondrite-normalized REE patterns of skarns are similar to those of the marbles, but the former are distinguished by much higher REE contents and more remarkable negative Eu anomalies. Those patterns were apparently not inherited from the marble protolith, but were controlled by garnets, which were determined by the hydrothermal solutions involved in the infiltration metasomatism. The hydrothermal fluids are characterized by having slightly right-hand dipping REE patterns, being enriched in LREE and having strongly negative Eu anomalies. The uptake of REE from hydrothermal fluids during the growth of garnet crystals resulted in the garnets having similar REE patterns to the hydrothermal fluids. Based on the spatial variation of REE in skarns and the structures of the hosting strata, we can get a better understanding of the transport path and pattern of the fluids involved in the formation of skarns and their related deposits. REE geochemistry investigation can help elucidate the genesis of skarns and skarn-related deposits. 展开更多
关键词 trace element geochemistry ree strata-bound skarn Dongguashan deposit Anhui China
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基于REE示踪法的工程堆积体坡面泥沙来源研究 被引量:1
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作者 魏育超 陈姿宇 +5 位作者 王子吟 魏宇航 张一博 王达未 谢永生 骆汉 《水土保持研究》 CSCD 北大核心 2024年第5期9-17,共9页
[目的]探究生产建设项目工程堆积体坡面侵蚀的泥沙来源,更有针对性地布设水土流失防治措施,减少人为扰动造成的水土流失。[方法]结合室内人工模拟降雨试验与REE(Rare Earth Elements)示踪技术,研究90 mm/h雨强下不同砾石含量[0(纯土),10... [目的]探究生产建设项目工程堆积体坡面侵蚀的泥沙来源,更有针对性地布设水土流失防治措施,减少人为扰动造成的水土流失。[方法]结合室内人工模拟降雨试验与REE(Rare Earth Elements)示踪技术,研究90 mm/h雨强下不同砾石含量[0(纯土),10%,20%,30%]工程堆积体坡面不同坡位的侵蚀特征及侵蚀贡献率。[结果](1)不同砾石含量堆积体各坡位侵蚀量均为下坡位最大,同时下坡位平均侵蚀贡献率(57.40%)大于上坡位和中坡位,表明下坡位是坡面泥沙的主要来源。(2)含砾石堆积体坡面中坡位和下坡位的侵蚀量显著小于纯土堆积体。含砾石堆积体坡面上坡位和中坡位的侵蚀贡献率显著+大于纯土堆积体坡面,下坡位侵蚀贡献率显著小于纯土堆积体坡面。(3)砾石含量对下坡位侵蚀量和贡献率的影响更显著(p<0.05)。含砾石堆积体中,20%砾石含量堆积体坡面上坡位和下坡位的侵蚀量显著大于10%,30%砾石含量堆积体。10%砾石含量堆积体坡面上坡位侵蚀贡献率显著大于20%,30%砾石含量堆积体坡面,下坡位侵蚀贡献率显著小于20%,30%砾石含量堆积体坡面。[结论]各砾石含量工程堆积体坡面中,下坡位侵蚀贡献率均最大,表明下坡位是工程堆积体坡面泥沙的主要来源,要加强工程堆积体下坡位的防护和治理。 展开更多
关键词 土壤侵蚀 ree 砾石含量 贡献率 坡位
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Heavy Metal Control in Domestic Rubbish by Source Screening and Suitability of Nutrient Elements as Turfgrass Medium 被引量:7
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作者 DUOLi-an ZHAOShu-lan GAOYu-bao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2005年第1期1-4,共4页
This paper, probing into heavy metal control in domestic rubbish by source screening and nutrient element analysis, revealed the feasibility of source control of heavy metals and the suitability of rubbish as turfgras... This paper, probing into heavy metal control in domestic rubbish by source screening and nutrient element analysis, revealed the feasibility of source control of heavy metals and the suitability of rubbish as turfgrass medium. Heavy metals in domestic rubbish were controlled by source screening before composting. The study consisted of a control with garden soil. The contents of main mineral elements and heavy metals in rubbish compost and control were determined by the method of ICP-AES. The results showed that heavy metal concentrations in rubbish were lower than those in garden soil, and little difference occurred between rubbish and garden soil in main mineral element concentrations. Based on this, it was concluded that rubbish compost was favorable for using as turfgrass medium and heavy metal control in rubbish by source screening was effective. 展开更多
关键词 domestic rubbish compost heavy metal screening control mineral element turfgrass medium
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Characteristics of mineral elements in shoots of three annual halophytes in a saline desert, Northern Xinjiang 被引量:4
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作者 Ke ZHANG ChunJian LI +3 位作者 ZhongShao LI FuHai ZHANG ZhenYong ZHAO ChangYan TIAN 《Journal of Arid Land》 SCIE CSCD 2013年第2期244-254,共11页
Halophytes are valuable salt-, alkali- and drought-resistant germplasm resources. However, the char- acteristics of mineral elements in halophytes have not been investigated as intensively as those in crops. This stud... Halophytes are valuable salt-, alkali- and drought-resistant germplasm resources. However, the char- acteristics of mineral elements in halophytes have not been investigated as intensively as those in crops. This study attempted to investigate the characteristics of mineral elements for annual halophytes during their growth period to reveal their possible physiological mechanisms of salt resistance. By using three native annual halophytes (Salsola subcrassa, Suaeda acuminate and Petrosimonia sibirica) distributed in the desert in Northern Xinjiang of China, the dynamic changes in the mineral element contents of annual halophytes were analyzed through field sampling and laboratory analyses. The results demonstrated that the annual halophytes were able to absorb water and mineral nutrients selectively. In the interaction between the annual halophytes and saline soil, the adaptability of the annual halophytes was manifested as the accumulation of S, Na and CI during the growth period and maintenance of water and salt balance in the plant, thus ensuring their selective absorption of N, P, K, Ca, Mg and other mineral nutrients according to their growth demand. By utilizing this property, halophyte planting and mowing (before the wilting and death periods) could bioremediate heavy saline-alkali soil. 展开更多
关键词 annual halophyte mineral elements DESERT saline-alkali soil Northern Xinjiang
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The application of three-dimensional seismic spectral decomposition and semblance attribute to characterizing the deepwater channel depositional elements in the Taranaki Basin of New Zealand 被引量:3
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作者 LI Quan WU Wei +4 位作者 YU Shui KANG Hongquan TONG Liqing CAO Xiangyang LIU Xiaolong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第9期79-86,共8页
In the past few years, three-dimensional(3-D) seismogram has become an essential tool for the interpretation of subsurface stratigraphy and depositional systems. Seismic stratigraphy in conjunction with seismic geom... In the past few years, three-dimensional(3-D) seismogram has become an essential tool for the interpretation of subsurface stratigraphy and depositional systems. Seismic stratigraphy in conjunction with seismic geomorphology has elevated the degree to which seismic data can facilitate geological interpretation, especially in a deepwater environment. Technologies such as time slicing and interval attribute analysis can enhance geomorphological interpretations, and, when integrated with stratigraphic analyses, can yield insights regarding distribution of seal and reservoir facies. Multiple attributes corendering can further bring out features of geological interest that other technologies may overlook. This method involves corender spectral decomposition components(SDC) with semblance attributes to describe the distribution of deepwater channel elements and the boundaries of deepwater sinuous channel. Applying this technology to four elements is observed:(1) point-bars,(2) migration of channel meander loops,(3) channel erosion/cut, and(4) avulsion. The planview expression of the deepwater channel ranges from low sinuosity to high sinuosity. Furthermore, this technology has enabled interpreters to visualize details of complex depositional elements and can be used to predict net-to-gross ratio in channel systems, which can be incorporated into borehole planning for exploration as well as development needs to improve risk management significantly. The technology is applied to the study area in an effort to illustrate the variety of interpretation technologies available to the geoscientist. 展开更多
关键词 deepwater channel spectral decomposition semblance depositional elements deepwater Taranaki Basin
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Geochemical studies on REE and trace elements from several Cu-Au deposits along the lower Yangtze metallogenic valley, central-southern Anhui Province 被引量:1
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作者 杨晓勇 黄晶 +1 位作者 孙立广 王奎仁 《Chinese Journal Of Geochemistry》 EI CAS 2007年第2期170-181,共12页
The Yangtze Valley was one of the most important metallogenic regions during the Jurassic-Cretaceous period in East China, where more than 200 polymetallic Cu-Fe-Au, Mo, Zn, Pb, Ag deposits have been found. Trace elem... The Yangtze Valley was one of the most important metallogenic regions during the Jurassic-Cretaceous period in East China, where more than 200 polymetallic Cu-Fe-Au, Mo, Zn, Pb, Ag deposits have been found. Trace elements were chemically analyzed and the relevant data were collected from literature for the Yanshanian (Mesozoic) igneous rocks which have close relationship with Cu-Au mineralization. Copper mineralization in the lower Yangtze Valley can be divided into three major types: skarn type, porphyry type and volcanic type. The porphyry type is of rare occurrence, such as the Shaxi porphyry copper deposit in the northern part of the lower Yangtze metallogenic valley. This paper focuses on the REE and trace element geochemistry of several Cu-Au deposits along the lower part of Yangtze metallogenic valley in Anhui. The results showed that there are differences in REE distribution for these four types of Cu-Au mineralization, which confine the sources of REE and trace elements as well as other mantle and transitional compatible elements. The results of both REE and trace element geochemical studies showed that these elements with different characteristics have different origins, probably representing different sources of Cu-Au deposits in the deep crust and upper mantle environments. The 40Ar/39Ar dating of one biotite sample gave an age of 131 Ma with a high level of confidence, which represents the age of formation of the Shaxi porphyrite intrusive with porphrytic Cu-Au mineralization, which is consistent with that of the majority of the adjacent acid intrusives with mass Cu-Au mineralization along the Yangtze metallogenic belt in the Yanshanian period (Mesozoic). This is the first attempt to use the high precision method to date the Shaxi porphyrite intrusive. 展开更多
关键词 安徽中南部 长江下游 铜-金矿床 成矿带 ree 微量元素 地球化学研究
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Geochemistry of the Rare Earth Elements (REE) Distribution in Terengganu Coastal Waters: A Study Case from Redang Island Marine Sediment 被引量:4
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作者 A. Nor Antonina N. A. M. Shazili +3 位作者 B. Y. Kamaruzzaman M. C. Ong Y. Rosnan F. N. Sharifah 《Open Journal of Marine Science》 2013年第3期154-159,共6页
A study on the rare earth elements (REEs) of Redang Island marine sediments was conducted in August 2011 during the premonsoon season. Bottom sediments were collected from 27 sampling stations on board UMT Discovery I... A study on the rare earth elements (REEs) of Redang Island marine sediments was conducted in August 2011 during the premonsoon season. Bottom sediments were collected from 27 sampling stations on board UMT Discovery II vessel using a Smith McIntyre grab and analyzed for rare earth elements (REEs) using inductively coupled plasma mass spectrometry (ICP-MS). Results showed that the REEs patterns in sediments reflected the source rock patterns with an overall order of abundance such as: light rare earth elements (LREE) > middle rare earth element (MREE) > high rare earth elements (HREE). The chondrite normalized patterns of REEs showed enrichment of LREEs over HREEs with La/Yb of 13.6 while the chondrite normalized value showed low (Gd/Yb)N ratios (2.12) which was illustrated in the flat HREE pattern. The chondrite normalized REE patterns of sediments showed the enrichment of LREE and depletion of HREE. From our findings, REEs concentrations in the study area were found to be of geogenic origins and the distributions were not influenced by anthropogenic sources. 展开更多
关键词 Rare Earth elements Marine SEDIMENTS Redang ISLAND MALAYSIA
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EFFECTS OF ALLOYING ELEMENTS ON CREEP OF TiAl ALLOYS WITH FINELAMELLAR STRUCTURES 被引量:2
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作者 J.N.Wang, B.Y.Huang and T.G.Nieh  National Key Laboratory for Powder Metallurgy, Central South University of Technology, Changsha 410083, China  Lawrence Livermore National Laboratory, P.O.Box 808, Livermore, CA 94550, U.S.A. 《中国有色金属学会会刊:英文版》 CSCD 1999年第S1期263-273,共11页
Creep experiments have been conducted on five powder metallurgy TiAl alloys with fine grains (65~80 μm), fine lamellar spacings (0.1~0.16 μm), and different compositions [Ti 47Al(+Cr, Nb, Ta, W, Si)] at temperatur... Creep experiments have been conducted on five powder metallurgy TiAl alloys with fine grains (65~80 μm), fine lamellar spacings (0.1~0.16 μm), and different compositions [Ti 47Al(+Cr, Nb, Ta, W, Si)] at temperatures of 760 ℃ and 815 ℃ and stresses from 35 to 723 MPa. Results show that at a given lamellar spacing 1% Nb(mole fraction) with 1% Ta and replacing 0.2% Ta with 0.2% W induced little effect, but addition of 0.3% Si decreased the creep resistance by a factor of 3~4 under otherwise identical conditions. These different effects of different alloying elements are interpreted in terms of the interaction of alloy segregants with misfit and/or misorientaion dislocations at the lamellar interface. That is, the interaction retards or facilitates the climb of interfacial dislocations, which is rate controlling during creep, depending on the size of the segregants relative to the host atoms. 展开更多
关键词 TIAL alloys FINE LAMELLAR structures CreeP ALLOYING elements
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Modelling of the relationship between trace elements and three species of sulfur in coal 被引量:1
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作者 Lu Xiao hua, Zeng Han cai National Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China Wei Lu xian Center of Microanalysis, Wuhan University of Automobile Industry, Wuhan, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第2期89-95,共7页
Based on the determination of several trace elements in coal particulate of different specific gravity, three variables regression equations relate the contents of trace elements Be, Cd, Co, Pb, Cu, Ni, As and three ... Based on the determination of several trace elements in coal particulate of different specific gravity, three variables regression equations relate the contents of trace elements Be, Cd, Co, Pb, Cu, Ni, As and three species of sulfur in coal were well established. For elements Cd, Co, Pb, Cu and Ni, the regression equations were successfully used for prediction of these trace elements in individual part of coal with different specific gravity. Factor analysis was also used to analyze the data sets. The results showed that a three factor model can interpret the data sets reasonably. Trace elements Cd, Co, Pb, Cu, Ni, inorganic sulfide and total sulfur in coal are high correlated with the first factor. Trace elements Be, sulfate and organic sulfide are high correlated with the second factor and trace elements Cr and As are high correlated with the third factor. The factors can be interpreted by the chemical properties of these elements. 展开更多
关键词 trace elements COAL regression analysis factor analysis.
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Characteristics of rare-earth elements (REE),strontium and neodymium isotopes in hydrothermal fluorites from the Bailashui tin deposit in the Furong ore field,southern Hunan Province,China 被引量:16
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作者 YUAN Shunda PENG Jiantang +5 位作者 HU Ruizhong BI Xianwu QI Liang LI Zhaoli LI Xiaomin SHUANG Yan 《Chinese Journal Of Geochemistry》 EI CAS 2008年第4期342-350,共9页
In this paper the authors present the REE concentrations and Sr and Nd isotopic compositions of fluorites from the Bailashui tin deposit of the Furong ore field,southern Hunan Province. The results showed that the tot... In this paper the authors present the REE concentrations and Sr and Nd isotopic compositions of fluorites from the Bailashui tin deposit of the Furong ore field,southern Hunan Province. The results showed that the total amount of REE in fluorites is usually low,ranging from 0.705 to 8.785 μg/g with the chondrite-normalized REE dis-tribution patterns similar to those of the Qitianling granites in the study area,characterized by LREE-enrichment patterns with pronounced negative Eu anomalies. The fluorites vary in Sr isotopic composition within the range of 0.7083-0.7091,the values are lower than those of the granites and higher than those of the host carbonate rocks in this area. The εNd(t) values of fluorites vary between -9.4 and +10.3,revealing that both the crust-and mantle-source materials were involved in the ore-forming hydrothermal fluids. Combined with previous studies on this ore deposit,the Bailashui tin deposit is temporally and spatially closely related with granitic magmatism in this area. The hydro-thermal fluorites are the product of fluid/rock interactions between granitic magmatic hydrothermal fluid and marine carbonate rocks. The REE and F in the ore-forming fluid were derived from the granites,whereas Sr in the ore-forming fluid came mainly from the granitic magmatic hydrothermal fluid and marine carbonate rocks,although variations in Sr isotopic composition cannot be explained by a simple mixture of these two end-members. Evidence demonstrated that the ore-forming fluids are of crustal-mantle mixing origin,but that the fluids were probably in-completely homogenized and this may be caused by inhomogeneous mixing of the fluids of different sources. 展开更多
关键词 萤石 同位素 锡沉淀 稀有地球元素
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Effect of homogenization treatment on microstructure evolution and the distributions of RE and Zr elements in various MgeLieREeZr alloys 被引量:10
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作者 Lei Bao Qichi Le +2 位作者 Zhiqiang Zhang Jianzhong Cui Qinxue Li 《Journal of Magnesium and Alloys》 SCIE EI CAS 2013年第2期139-144,共6页
Mge3Lie0.4Zr alloys containing RE elements(Gd,La,Nd)(Mge3LieREe0.4Zr alloys)are investigated to reveal the influence of homogenization treatment on microstructures and distributions of RE,Zr elements.It is found that... Mge3Lie0.4Zr alloys containing RE elements(Gd,La,Nd)(Mge3LieREe0.4Zr alloys)are investigated to reveal the influence of homogenization treatment on microstructures and distributions of RE,Zr elements.It is found that 300C24 h homogenization treatment shows better improvement on the microstructure including the refinement of grain size,the dispersion of cellular dendrite and low melting point particles.Before treatment,La and Nd segregate effectively at grain boundary and Zr segregates in the form of precipitates.Homogenization treatment induces the reduction of RE segregation.However,the segregation of Zr in precipitates cannot be abated due to the relatively low diffusion rate compared with RE elements. 展开更多
关键词 MgeLi based alloys RE elements Homogenization treatment Microstructure Micro segregation
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Enhancement Effects of Three Rare Earth Elements on the Growth of Chaetoceros Mulleri 被引量:1
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作者 Qu Keming(曲克明) +1 位作者 Xin Fuyan(辛福言) 《Marine Science Bulletin》 CAS 2001年第2期83-88,共6页
Enhancement effects of rare earth elements on the growth of Chaetoceros mulleri is studied in this paper. The results show that all of the light, middle and heavy rare earth elements have similar enhancement effect on... Enhancement effects of rare earth elements on the growth of Chaetoceros mulleri is studied in this paper. The results show that all of the light, middle and heavy rare earth elements have similar enhancement effect on the growth of Chaetoceros mulleri, with the beneficial concentrations of La, Gd and Yb being 7.28~87.40 μ mol/L, 6.36~57.23 μ mol/L and 5.78~17.34 μ mol/L. The optimum concentrations of La, Gd and Yb are 7.28 ~50.98 μ mol/L,31.80~44.52 μ m ol/L and 5.78~17.34 1μ mol/L, respectively. When the concentrations of La, Gd and Yb are 7.28~87.40 μ mol/L, 6.36~57.23 μ mol/L and 5.78~ 17,34 μ mol/L, the concentrations of chlorophyll have increased by 9.3~47.0%, 33.4~44.3%, and 36.5~40.3%, respectively as compared with the control group. The mechanism of enhancement of rare earth elements on the growth ot Chaetoceros mulleri is also discussed in this paper. 展开更多
关键词 RARE EARTH element CHAETOCEROS mulleri ENHANCEMENT
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Analysis of the geometrical dependence of auxetic behavior in reentrant structures by finite elements 被引量:5
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作者 V.H.Carneiro H.Puga J.Meireles 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第2期295-300,共6页
Materials with a negative Poisson's ratio(PR)are called auxetics;they are characterized by expansion/contraction when tensioned/compressed.Given this counterintuitive behavior,they present very particular character... Materials with a negative Poisson's ratio(PR)are called auxetics;they are characterized by expansion/contraction when tensioned/compressed.Given this counterintuitive behavior,they present very particular characteristics and mechanical behavior.Geometrical models have been developed to justify and artificiall reproduce such materials' auxetic behavior.The focus of this study is the exploration of a reentrant model by analyzing the variation in the PR of reentrant structures as a function of geometrical and base material parameters.It is shown that,even in the presence of protruding ribs,there may not be auxetic behavior,and this depends on the geometry of each reentrant structure.Values determined for these parameters can be helpful as approximate reference data in the design and fabrication of auxetic lattices using reentrant geometries. 展开更多
关键词 Auxetic Poisson’s ratio reentrant Finite element analysis Elasticity
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Geochemical Characteristics of the Trace and Rare Earth Elements in Reef Carbonates from the Xisha Islands(South China Sea): Implications for Sediment Provenance and Paleoenvironment 被引量:2
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作者 BI Dongjie ZHAI Shikui +5 位作者 ZHANG Daojun XIU Chun LIU Xinyu LIU Xiaofeng JIANG Longjie ZHANG Aibin 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第6期1291-1301,共11页
Based on the concentrations of the trace elements,rare earth elements(REE),and Sr isotopic compositions in reef carbonates from the well‘Xike-1’reef core of the Xisha Islands,the constraints on sediment provenance a... Based on the concentrations of the trace elements,rare earth elements(REE),and Sr isotopic compositions in reef carbonates from the well‘Xike-1’reef core of the Xisha Islands,the constraints on sediment provenance and paleoenvironment were defined.Variations of the terrigenous input into the paleoseawater were traced in detail and the paleoenvironment and sediment provenance were further investigated.The results show that the HREE/LREE values in the reef carbonates are negatively associated with their Th and Al concentrations;however,their Al and Th concentrations show positive correlation.The lowest 87 Sr/86 Sr values in the reef carbonates generally coincide with the lowest values of Al,Th concentrations and the highest values of HREE/LREE.These data indicate that the HREE/LREE,Al concentrations,and Th concentrations of the reef carbonates are useful indexes for evaluating the influence of the terrigenous inputs on the seawater composition in the study area.From top to bottom,the changing process of the HREE/LREE values and Al,Th concentrations can be divided into 6 intervals;they are H1(0–89.30 m,about 0–0.11 Myr),L1(89.30–198.30 m,about 0.11–2.2 Myr),H2(198.30–374.95 m,about 2.2–5.3 Myr),D(374.95–758.40 m,about 5.3–13.6 Myr),L2(758.40–976.86 m,about 13.6–15.5 Myr),and H3(976.86–1200.00 m,about 15.5–21.5 Myr).Moreover,the changing trend of the HREE/LREE values coincides with that of the seawater δ^13C values recorded by benthonic foraminiferal skeletons from the drill core of ODP site 1148 in the South China Sea(SCS),but not with that of the seawaterδ18O values.The high uplifting rates of the Qinghai-Tibet Plateau coincide with the high Th and Al concentrations and the low HREE/LREE values in the reef carbonates.These data indicate that the main factors controlling the changes of terrigenous flux in the SCS are the tectonic activities associated with Qinghai-Tibet Plateau uplifting and the variations of uplifting rates rather than paleoclimatic changes. 展开更多
关键词 TRACE and rare earth elements paleoenvironmental and sediment provenance reeF CARBONATES the South China Sea(SCS) the UPLIFT of Qinghai-Tibet Plateau
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