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贵州务-正-道地区铝土矿含矿岩系中三稀元素赋存状态、富集机理及资源潜力 被引量:34
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作者 金中国 刘玲 +5 位作者 黄智龙 刘辰生 郑明泓 谷静 邹林 王林 《地质学报》 EI CAS CSCD 北大核心 2019年第11期2847-2861,共15页
黔北务-正-道地区铝土矿含矿岩系为下二叠统大竹园组,与下伏志留系下统韩家店组或上石炭统黄龙组及上覆中二叠统梁山组均呈假整合接触,古沉积环境主要为浅湖相,矿床成因属古风化壳沉积型。勘查实践及研究表明:①含铝岩系的各类岩石、矿... 黔北务-正-道地区铝土矿含矿岩系为下二叠统大竹园组,与下伏志留系下统韩家店组或上石炭统黄龙组及上覆中二叠统梁山组均呈假整合接触,古沉积环境主要为浅湖相,矿床成因属古风化壳沉积型。勘查实践及研究表明:①含铝岩系的各类岩石、矿石中均富含Li、Ga、Sc、REE等三稀元素,在空间分布及不同矿石中含量变化大,相差1~3个数量级。Li在研究区东、西两侧含量相对高,常富集于含矿岩系上部及矿体中致密块状、豆鲕状矿石中;Ga在研究区北侧及含矿岩系中部较富集,Sc在道真沙坝-平木山一带富集程度高,在含矿岩系中含量变化小;REE相对富集于南部、显著富集于含矿岩系的下部。②含矿岩系形成于古赤道附近气候温湿、开放的氧化环境,铝矿物及高岭石、蒙脱石等富铝黏土矿物丰富,促进Li、Ga、Sc和REE等三稀元素以离子吸附态形式随铝土矿脱硅、去铁、降硫的成矿过程同迁移、同富集;同时由于Li、Ga、Sc、REE等三稀元素与Al、Zr、Ti、Nb、Ta、Hf、Ti、Cr、Th、U等亲石元素离子半径相近,地球化学性质相似,在铝土矿成矿过程中可能部分以类质同象形式赋存。③次生淋滤改造作用及环境pH变化,是促进独立稀土矿物形成及REE在含矿岩系底部富集的重要因素,含矿岩系下部的富稀土层中应有大量稀土以独立矿物存在(特别是∑REE>800×10-6的地段);古沉积环境、成岩成矿期后的地形地貌及构造运动影响约束了Li、Ga、Sc和REE的不均匀分布。④以含铝岩系为评价对象,研究区Li、Ga、Sc资源潜力及潜在经济价值巨大。 展开更多
关键词 含铝岩系 三稀元素 赋存状态 富集机理 资源潜力 务-正-道地区
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How far has the globe gone in achieving One Health?Current evidence and policy implications based on global One Health index 被引量:1
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作者 Qiyu Zhang jingshu Liu +41 位作者 Lefei Han Xinchen Li chensheng Zhang Zhaoyu Guo Anqi Chao Chenxi Wang Erya Wan Fumin Chen Hanqing Zhao Jiaxin Feng jingbo Xue Lulu Huang jin Chen Zhishan Sun Zile Cheng jingxian Yin Zhengze He Liangyu Huang Logan Wu Siwei Fei Siyu Gu Tiange Jiang Tianyun Li Weiye Chen Nan Zhou Ne Qiang Qin Li Runchao He Yi Zhang Min Li Xiangcheng Wang Kokouvi Kassegne Yongzhang Zhu Leshan Xiu Qinqin Hu Kun Yin Shang Xia Shizhu Li Zhaojun Wang Xiaokui Guo Xiaoxi Zhang Xiao-Nong Zhou 《Science in One Health》 2024年第1期126-133,共8页
Background:In the 21st century,as globalization accelerates and global public health crises occur,the One Health approach,guided by the holistic thinking of human-animal-environment and emphasizing interdisciplinary c... Background:In the 21st century,as globalization accelerates and global public health crises occur,the One Health approach,guided by the holistic thinking of human-animal-environment and emphasizing interdisciplinary collaboration to address global health issues,has been strongly advocated by the international community.An immediate requirement exists for the creation of an assessment tool to foster One Health initiatives on both global and national scales.Methods:Built upon extensive expert consultations and dialogues,this follow-up study enhances the 2022 global One Health index(GOHI)indicator system.The GOHI framework is enriched by covering three indices,e.g.external drivers index(EDI),intrinsic drivers index(IDI),and core drivers index(CDI).The comprehensive indicator system incorporates 13 key indicators,50 indicators,and 170 sub I-indicators,utilizing a fuzzy analytic hierarchy process to ascertain the weight for each indicator.Weighted and summed,the EDI,IDI,and CDI scores contribute to the computation of the overall GOHI 2022 score.By comparing the ranking and the overall scores among the seven regions and across 160 countries/territories,we have not only derived an overall profile of the GOHI 2022 scores,but also assessed the GOHI framework.We also compared rankings of indicators and sub Iindicators to provide greater clarity on the strengths and weaknesses of each region within the One Health domains.Results:The GOHI 2022 performance reveals significant disparities between countries/territories ranged from 39.03 to 70.61.The global average score of the GOHI 2022 is 54.82.The average score for EDI,IDI,and CDI are 46.57,58.01,and 57.25,respectively.In terms of global rankings,countries from North America,Europe and Central Asia,East Asia and Pacific present higher scores.In terms of One Health domains of CDI,the lowest scores are observed in antimicrobial resistance(median:43.09),followed by food security(median:53.78),governance(median:54.77),climate change(median:64.12)and zoonotic diseases(median:69.23 展开更多
关键词 Global One Health index(GOHI) Zoonotic diseases Antimicrobial resistance Food security Climate change
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黔北务正道地区沉积型铝土矿富集成矿主控因素分析 被引量:4
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作者 刘辰生 肖明国 +2 位作者 苏娟 金中国 郭建华 《沉积学报》 CAS CSCD 北大核心 2018年第2期302-309,共8页
黔北务正道地区铝土矿是我国超大型铝土矿矿床,该矿床为沉积型铝土矿,其成矿过程主要受到沉积相和海平面变化的影响。通过对研究区铝土矿含矿岩系岩性和地球化学分析,认为该区铝土矿主要形成于湖泊相滨浅湖亚相,即铝土矿形成于淡水环境... 黔北务正道地区铝土矿是我国超大型铝土矿矿床,该矿床为沉积型铝土矿,其成矿过程主要受到沉积相和海平面变化的影响。通过对研究区铝土矿含矿岩系岩性和地球化学分析,认为该区铝土矿主要形成于湖泊相滨浅湖亚相,即铝土矿形成于淡水环境,含矿岩系的绿泥石黏土岩和铝土岩形成于扇三角洲和潮坪相。水动力条件和沉积分异作用控制着铝土矿类型:颗粒状铝土矿形成于滨湖等水动力较强的区域,而土状铝土矿形成与水动力较弱的浅湖区。海平面上升旋回以绿泥石岩和铝土岩沉积为主,而海平面下降旋回以铝土矿沉积为主。海平面下降旋回的跨时远大于海平面上升旋回,这也说明铝土矿的形成是漫长的风化过程。研究区铝土矿含矿岩系最多可识别出3个海平面升降旋回,这3个旋回与研究区周缘同期的碳酸盐岩和碎屑岩沉积旋回具有一致性和可对比性。 展开更多
关键词 铝土矿含矿岩系 湖泊相 海平面变化 沉积旋回 颗粒状铝土矿
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铝合金导管扩口柔性夹持工装技术 被引量:1
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作者 唐臣升 孙朝海 +2 位作者 孙进 白玉珍 赵丹 《工具技术》 北大核心 2023年第10期118-122,共5页
为解决铝合金导管扩口加工夹持质量差的问题,进行系统的铝合金导管扩口加工柔性夹持方法及工艺装备研究,研制出铝合金导管扩口加工柔性夹具。通过加工试验优化铝合金导管扩口加工柔性夹具的结构及参数,实现铝合金导管扩口加工效率与质... 为解决铝合金导管扩口加工夹持质量差的问题,进行系统的铝合金导管扩口加工柔性夹持方法及工艺装备研究,研制出铝合金导管扩口加工柔性夹具。通过加工试验优化铝合金导管扩口加工柔性夹具的结构及参数,实现铝合金导管扩口加工效率与质量的提高。 展开更多
关键词 铝合金 导管 扩口 滚压 工艺装备
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Global and regional controls on carbon-sulfur isotope cycling during SPICE event in south China
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作者 Xianfeng TAN Long LUO +7 位作者 Hongjin CHEN Jon GLUYAS Zihu ZHANG chensheng jin Lidan LEI Jia WANG Qing CHEN Meng LI 《Frontiers of Earth Science》 SCIE CSCD 2023年第3期713-726,共14页
The positive S-isotopic excursion of carbonate-associated sulfate(δ34S_(CAS))is generally in phase with the Steptoean positive carbon isotope excursion(SPICE),which may reflect widespread,global,transient increases i... The positive S-isotopic excursion of carbonate-associated sulfate(δ34S_(CAS))is generally in phase with the Steptoean positive carbon isotope excursion(SPICE),which may reflect widespread,global,transient increases in the burial of organic carbon and pyrite sulfate in sediments deposited under large-scale anoxic and sulphidic conditions.However,carbon-sulfur isotope cycling of the global SPICE event,which may be controlled by global and regional events,is still poorly understood,especially in south China.Therefore,theδ13CPDB,δ18OPDBδ34S_(CAS),total carbon(TC),total organic carbon(TOC)and total sulfate(TS)of Cambrian carbonate of Waergang section of Hunan Province were analyzed to unravel global and regional controls on carbon-sulfur cycling during SPICE event in south China.Theδ34S_(CAS)values in the onset and rising limb are not obviously higher than that in the preceding SPICE,meanwhile sulfate(δ34S_(CAS))isotope values increase slightly with increasingδ13CPDB in rising limb and near peak of SPICE(130–160 m).The sulfate(δ34S_(CAS))isotope values gradually decrease from 48.6‰to 18‰in the peak part of SPICE and even increase from 18%to 38.5%in the descending limb of SPICE.The abnormal asynchronous C−S isotope excursion during SPICE event in the south China was mainly controlled by the global events including sea level change and marine sulfate reduction,and it was also influenced by regional events such as enhanced siliciclastic provenance input(sulfate),weathering of a carbonate platform and sedimentary environment.Sedimentary environment and lithology are not the main reason for global SPICE event but influence theδ13CPDB excursion-amplitude of SPICE.Sea level eustacy and carbonate platform weathering probably made a major contribution to theδ13CPDB excursion during the SPICE,in particularly,near peak of SPICE.Besides,the trilobite extinctions,anoxia,organic-matter burial and siliciclastic provenance input also play an important role in the onset,early and late stage of SPICE event. 展开更多
关键词 sulfate isotope excursion terrigenous matter carbonate platform weathering sea level change transitional slope environment Waergang section
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