共查询到20条相似文献,搜索用时 718 毫秒
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金属矿山开采往往造成矿山土壤严重的重金属污染,以铅锌矿为例,阐述了重金属污染的产生和赋存状态、重金属污染土壤的修复技术,重点介绍了重金属污染土壤的植物修复治理措施,介绍了超富集植物筛选方面国内外的有关研究进展,指出了目前尚未解决的问题及未来发展趋势。 相似文献
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3种植物对铀尾渣的耐受性研究 总被引:2,自引:0,他引:2
铀尾渣营养贫乏、重金属含量高,其堆存区植被缺乏,污染物移迁扩散严重.在铀尾渣堆存区域重建植被可防止污染物扩散.针对铀尾渣堆积区的植被重建,选用美洲商陆(Phytolacca americana)、羽叶鬼针草(Bidens maximowicziana)和东方蓼(Polygonum orientale)3种植物,将铀尾渣与土壤按不同比例混合改良,用作栽培基质,进行盆栽试验,研究这3种植物对铀尾渣的耐受性以及基质改良对植物生长的影响.分析株高、生物量和叶绿素含量变化,发现羽叶鬼针草对铀尾渣的耐受性强于另外两种植物.铀尾渣中加入土壤有利于3种植物生长.在T60(铀尾渣比例为60%)改良方式中,这3种植物生长最好.利用这3种植物进行植被重建时,建议采用T60方式改良铀尾渣. 相似文献
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采集淮南潘一煤矿塌陷复垦区6种常见的菊科植物,通过测定植物及根区土壤中的重金属,研究重金属在植物体内的吸收、分布和富集特征。结果表明,潘一煤矿塌陷复垦区土壤已受到不同程度的重金属污染,6种菊科植物对重金属的富集和转移,因植物种类、部位和金属类型而不同;与普通植物体中重金属含量相比,6种菊科植物表现出了对Ni、Cr、Pb、Cd积累特性;由于受成土母质和研究区域土壤环境质量的影响,调查的6种菊科植物地上部分重金属含量均未达到超积累植物的临界含量标准,没有筛选出超积累植物。但是调查发现,洋姜(Helianthus tuberosus)和一年蓬(Erigeron annuus)对Cd元素同时具备超累积植物的两个基本特征,这两种植物的生物量大,生长速度快,对环境的适应性强,可以列为煤矿塌陷复垦区Cd污染修复先锋植物,其植物修复潜力值得进一步研究。 相似文献
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<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth 相似文献
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《中国稀土信息(英文版)》2014,(6)
正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products 相似文献
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YANG Li 《中国稀土信息(英文版)》2014,(6)
<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy 相似文献
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Gao Wei 《中国稀土信息(英文版)》2014,(11)
正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium 相似文献
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《中国稀土信息(英文版)》2014,(8)
正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared 相似文献
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高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。 相似文献
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Chen Zhanheng 《中国稀土信息(英文版)》2014,(5)
<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586 相似文献
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Bai Wenping 《中国稀土信息(英文版)》2014,(12)
<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH 相似文献
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《中国稀土信息(英文版)》2014,(9)
正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to 相似文献
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研究工作面瓦斯涌出规律对工作面瓦斯治理有重要意义。为了得到唐口煤矿深部3号煤层复杂开采条件下工作面回采时期瓦斯涌出时空演化规律,选取6304工作面作为对象,采用实测方法研究6304工作面瓦斯涌出规律。结果表明:6304工作面瓦斯涌出量为6.534 m3/min,其中煤壁占34.27%,落煤占29.62%,采空区占36.11%;沿工作面倾向由低到高,瓦斯浓度整体为上升趋势,其中1—76号架工作面瓦斯浓度小于0.20%,76—102号架瓦斯浓度上升明显,最大为0.387%;上隅角的后部采空区是工作面的瓦斯主要涌出源,上隅角1号测点瓦斯浓度0.78%,上隅角周边3号、5号、7号、8号、9号测点瓦斯浓度平均为0.643%;周期来压时,上隅角瓦斯相对平时较高。研究为针对性的瓦斯分源监控与灾害防治提供基础。 相似文献