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含钕稀土有机高分子的研究进展 总被引:1,自引:0,他引:1
稀土高分子是一类具有许多优异性质和很高应用价值的功能材料 ,其开发和应用前景十分迷人。文章对含钕的稀土有机高分子近几十年来的研究发展情况作了综述 相似文献
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稀土在石化工业中的应用回顾与发展建议 总被引:2,自引:0,他引:2
概要地回顾了稀土在石化工业中的应用情况和取得的成绩,根据我国稀土资源的优势和市场需求,建议进一步大力发展稀土在催化剂、支农产品、工业废气、废水等方面应用的工业化开发,将我国稀土资源优势变成产业化优势和市场优势,从而促进支柱产业石化工业的发展,满足相关行业发展的需要。 相似文献
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铝,镁轻合金中的稀土 总被引:11,自引:3,他引:11
综述了稀土-镁和稀土-铝合金的晶体化学、热力学和相图数据,根据其前景特别注意了富镁,富铝稀土合金及添加稀土对合金性能的影响,报道了若干稀土-鲜、稀土-铝及含两个没稀土的镁、铝合金的研究结果。对富镁、富铝的二元和三元合金相的结晶及形成规律进行了总结和讨论,并对有确定结构的合金精细设计和可能的应用提出了建议。 相似文献
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Archana Kumari Devendra Deo Pathak Sanchita Chakravarty Jae-chun Lee 《Separation & Purification Reviews》2019,48(2):91-121
Europium (Eu), one of the most significant rare earth (RE) elements, has wide applications as functional material in phosphor production, majorly used in fluorescent lamps, computer monitors, televisions etc. Eu is one of the three divalent lanthanides (along with Yb and Sm) having a reduction potential higher than ?2 V. This possibility of Eu reduction is attributed to a relatively stable half-filled 4f7 electronic configuration, thus providing a high stabilization energy and selective recovery. But the Eu recuperation from natural minerals is either accompanied with other REs or Eu is recovered as a group of light REs. Selective recovery of Eu has sparked the progress for its reutilization through recycling of secondary resources. The perspectives of reclaiming Eu as a value added product from various sources using different pyro-hydro or hybrid techniques are discussed. The systematic research and salient findings on methods, viz., reduction, leaching, solvent extraction, as well as combined methods scaled-up to commercial scale to recover Eu, are also reported with recommendations. Thus, this comparative as well as summarized review hopes to help researchers to develop feasible processes for Eu recovery. 相似文献
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To understand the influence of impurities and rare earth elements in nature on the intergranular corrosion of the zinc-aluminum alloys, taking efficient methods to retard the inter granular corrosion, the atomic cluster of α phase grain boundary including impurities (Pb, Sn, Cd), rare earth elements (La, Y) and phase grain was constructed by computer programming based on the coincidence-site lattice theory. The recursion method was used to calculate the charge transfer over the grain boundary of α phase, and discuss influence of impurities (Pb, Sn, Cd) and Rare Earth elements (La, Y) on the electrode-potential of Zn and Al. The results shows that impurity elements (Pb, Sn, Cd) can increase the charge transfer between atoms over the grain boundary, leading to the large difference of electrode-potential between Zn and Al. Therefore the eroding is speeding up, but the RE element can reduce the charge transfer between atom sover the grain boundary, and lower the difference of electrode-potential between Zn and Al. Thus RE element is of the role of restraining the inter granular corrosion of zinc-aluminum alloys. 相似文献
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稀土元素是一个包含了由钪、钇与镧系共17种元素的系列统称,它们既具有本质上的物理化学相似性,也具有各自独特和多样的电子结构。 从化学水平上讲,稀土离子的特性决定了稀土永磁、磁致冷、超导、热释电、光学制冷、非线性光学、催化等高新技术应用的本质;从材料水平上讲,稀土功能材料是实现这些技术应用的基础。 从科技发展要求来讲,稀土功能材料的研发是实现稀土资源高质量发展的最重要途径。 本文从稀土离子特性出发,利用轨道杂化模型构建稀土离子与稀土功能材料之间的基本关系,总结了近年来不同应用领域中稀土离子在稀土功能材料的组成设计与性能优化方面的研究进展。 相似文献
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A preconcentration method for trace amounts of rare earth elements (REs) based on the substoichiometric precipitation of calcium oxalate was developed. RE(III) was quantitatively coprecipitated with calcium oxalate which had been precipitated from the calcium of a macrocomponent in a biological sample by addition of a substoichiometric amount of oxalate. In this way high selectivity for RE(III) from other elements was achieved. The method was applied to the neutron activation analysis of a biological sample (NBS SRM 1572 Citrus Leaves), and Sc, La, Ce, Pf, Nd, Sm, Eu, Th, Dy, Ho, Yb and Lu were determined with a relative standard deviation of less than 5%. 相似文献
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稀土在工业诸多领域中发挥着关键作用,在增材制造材料和介电材料等高新技术领域均显示出可期的应用前景。稀土元素的分离是衔接稀土资源与高性能稀土功能材料的关键过程,所以高效提纯稀土元素变得尤为重要。本文梳理了化学沉淀法、离子交换与吸附法、萃取色层法、溶剂萃取法、液膜分离法这些经典方法和化学气相传输法、氧化还原法、萃取沉淀法、微生物法、非平衡溶剂萃取法这些新技术方法的优缺点和适用性,侧重分析了这些技术方法在节能减排方面的最新研究情况,并展望了稀土分离提纯领域的重点发展方向,以期为稀土资源的绿色高效开发利用提供依据和借鉴。 相似文献
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大豆中稀土元素分配规律研究 总被引:1,自引:0,他引:1
祁俊生 《广东微量元素科学》2000,7(8):24-28
研究了大豆中稀土元素(La、Ce、Nd、Y、Gd)的含量分布规律。结果表明:大豆各部位稀土含量分布一般规律为:根>茎>夹壳>夹果;大豆在生长不同期吸收稀土的能力大小为:幼苗期>分枝期>成熟期。总之,稀土元素在大豆中不易迁移,主要集中在根部,果实中含量甚微,因而施用稀土微肥,不会影响食用粮食的安全问题。 相似文献
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我国现行主要稀土矿分解流程的经济技术指标分析 总被引:3,自引:1,他引:3
对我国主要稀土矿分解方式进行了阐述,着重讨论了离子吸附型稀土矿、氟碳铈矿和包头白云鄂博矿的典型前处理方式的经济技术指标,对目前最常用前处理方法的投资、生产单耗、成本进行了统计和分析。离子吸附型稀土矿赋存状态奇特,富含高价值中重稀土,但品位低、分布广,多以离子交换的方式开采,环境保护面临的突出问题是植被恢复和废水达标排放;北方矿以轻稀土为主,价值相对较低,原矿品位高,分布集中,露天开采后多以重、磁、浮选工艺选出精矿,然后用煅烧和酸浸结合的工艺进行冶炼,废水和废气以及废渣是环境保护的主题。这些不同稀土矿前处理工艺的特点、发展历史以生产消耗等情况,既可作为稀土生产的投资参考,也可作为稀土企业挖潜改造、提高生产管理水平和环境保护水平的重要依据。 相似文献