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战略性新兴产业的迅速发展,无论对中国还是对世界经济都具有全局带动和重大引领作用,而稀土当之无愧地成为战略性新兴产业的重要支柱性矿产之一。随着中国稀土产业的不断发展壮大以及政策宏观调控的作用,加之终端消费产业的需求拉动稀土消费,我国的稀土需求一直呈增长态势,而新兴领域的应用的不断开拓,使稀土资源需求结构也发生的很大变化,本文通过分析近年来稀土资源需求变化,为下一步稀土资源管理提出相关政策建议。 相似文献
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稀土元素因其丰富的光、电、磁、热特性被广泛应用于传统工业领域及新兴产业领域,稀土资源被多数国家认定为是战略性资源或关键性矿产资源。我国是稀土资源大国,无论从储量、产量还是消费量上来看我国都居于世界前列。从资源管理角度我国稀土资源战略定位可以概括为有效保护和合理利用稀土资源,保障资源供应安全;坚持国家利益最大化,优先满足国内应用需求;节约集约利用资源,在开发利用的同时保护生态环境。本文初步探讨了以计划为基础和以市场为导向的两种实现稀土资源战略的实施路径,并就此提出稀土产业发展的相关建议 相似文献
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稀土由于具有独特的物理化学性质,被广泛地应用于电子、冶金、机械、石油化工等多个领域。随着其应用范围的不断扩大,稀土元素不可避免地进入环境,并可能通过食物链、呼吸、皮肤接触等多种途径对人类健康产生威胁。因此,研究稀土元素的生物毒害性有利于增强对稀土元素的全面认识,对评估稀土环境风险具有重要意义。本文综述了近年来稀土元素的生物毒害性研究进展,主要包括:稀土元素对植物、动物和人体的生物毒害效应及其机制;稀土元素的不同暴露方式及其健康影响;稀土元素的安全临界剂量研究进展。当前由于人们对稀土元素的生物毒害效应认识不足,因此,未来应加强对稀土不同暴露方式下的人体健康效应的关注。尤其需要注意在离子吸附型稀土矿大面积出露的华南地区,自然区的暴露作用不容忽视,特别要警惕人群的摄食量和与稀土元素可能有关的病症;基于现有对稀土暴露方式的认识,优化作业流程并加强管理,减少甚至切断相关稀土暴露源;加快建立并推行稀土安全临界剂量标准,为稀土污染评价和环境治理提供参考。 相似文献
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近年来,我国地质样中痕量稀土发射光谱分析有了较大进展,成为稀土分析化学中最活跃的领域之一。这里,作者仅就手头掌握的部分文献,对此进展作一评述。 相似文献
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<正>稀土是我国优势矿产资源,是工业“维生素”,被誉为人类的“希望之土”。其中,重稀土在尖端军事、航空航天和高新科技领域具有无可替代的作用,是世界各工业强国公认的关键金属矿产。目前,全球中、重稀土主要来源于我国南方的离子吸附型稀土矿床,该类型稀土矿主要赋存于燕山期花岗岩风化壳中,具有分布广、储量大、埋藏浅、开采成本低等特点,保障了90%以上中、重稀土国际市场的供给。但风化壳中以吸附态存在的稀土离子极不稳定,一方面原地铵法浸矿会导致矿区内稀土和铵离子的大量泄露;另一方面,稀土高丰度区内因大型基建及挖掘导致风化壳破坏,稀土离子受酸雨等影响活化失稳。以上两方面均使稀土离子极易扩散进入周边环境,造成污染, 相似文献
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Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
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The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引:4,自引:0,他引:4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
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Muriel Rocher Stéphane Baize Stéphane Jaillet Edward Marc Cushing Yannick Lozach Francis Lemeille 《Comptes Rendus Geoscience》2003,335(8):701-708
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003). 相似文献
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正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level 相似文献
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正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7), 相似文献
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正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci- 相似文献
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正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli- 相似文献
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正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.) 相似文献
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正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861 相似文献