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文章主要介绍了熔盐氯化物电解金属的过程中,金属配分镧、铈波动产生的原因及在生产实践中解决的办法和注意事项. 相似文献
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采用真空蒸发镀膜法在不锈钢基体上制备金属铈薄膜,利用扫描电子显微镜(SEM)和X射线衍射仪(XRD)研究铈薄膜的形貌和物相结构,通过俄歇电子能谱仪(AES)和X射线光电子能谱仪(XPS)测量元素形态及膜层深度。分析结果表明:金属铈薄膜表面致密,与不锈钢基体紧密结合,膜层的厚度约为24μm;金属铈薄膜的表面已经被氧化,氧化膜的厚度约为340 nm,其成分主要由CeO_2组成,也含有少量的Ce_2O_3。 相似文献
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在热镀锌镀液中加入微量铈,对其所形成的镀层在酸性和中性介质中的耐腐蚀性进行了测定和分析.结果表明,在镀液中加入约0.05%的金属铈,能显著提高锌镀层在酸性介质中的耐腐蚀性能;在镀液中加入约0.1%的金属铈,锌镀层在中性介质中的耐腐蚀性能最好. 相似文献
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铥镱镥富集物的镧铈热还原研究 总被引:1,自引:0,他引:1
计算了镧、铈热还原铥镱镥富集物制取金属镱的基本热力学条件;并成功地进行了有关热还原试验.试验结果表明,在适宜技术条件下,可以获得纯度高于98%的金属镱,其金属直收率为85%~90%。文内探讨了原料中各主要稀土成分及其他非稀土杂质在还原时的行为走向,同时对镧、铈热还原的实用性作了简要的比较。 相似文献
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采用真空感应炉对金属热还原法制备的V-Ti-Fe合金进行精炼,考察金属铈对精炼效果的影响。结果表明,铈可有效脱除合金中的氧杂质,减少合金内的富钛相和硅偏聚相,降低合金的成分偏析,促进合金的吸氢活化。随铈用量的增加,脱氧效果也逐渐增强,储氢容量得到提升,当铈添加量达到合金用量的5%时,氧含量降到了0.05%,最大吸氢量和有效放氢量分别达到3.36%和1.85%。 相似文献
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采用化学成分分析、热力学计算、显微观察、硬度测定的方法,研究了稀土铈在氧和硫质量分数均小于0.000 6%的超洁净IF钢中的存在状态,以及铈对钢的Al2O3夹杂物、显微组织和硬度的影响机理。结果表明,当铈质量分数为0.006 1%~0.009 3%时,铈的固溶量为0.004 1%~0.006 7%,约70%的铈以固溶形态存在,其余的铈以夹杂物形态存在,钢中不存在铈铁金属间化合物。铈能够将Al2O3夹杂物转化为尺寸较小的球状CeAlO3夹杂物,具有变质夹杂物的作用。铈具有改善IF钢的显微组织的作用,钢中铈的固溶量越大,晶粒越细。与不含铈的IF钢相比,当钢中铈质量分数为0.006 1%和0.009 3%时,钢的洛氏硬度分别提高了7.6%和12.7%。 相似文献
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The large particle cerium oxide was prepared using oxalic acid as precipitation agent. The effects of preparation conditions on the particle size of cerium oxide were discussed. The results showed that the particle size of cerium oxide could be controlled effectively by the temperature, acidity of the solution, aging time, etc. The optimized preparation process of large particle cerium oxide was obtained. The cerium oxide with size between 50 μm to 150 μm was prepared by the process. Moreover, the cerium oxide particles were dispersed uniformly. 相似文献
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The large particle cerium oxide was prepared using oxalic acid as precipitation agent. The effects of preparation conditions on the particle size of cerium oxide were discussed. The results showed that the particle size of cerium oxide could be controlled effectively by the temperature,acidity of the solution,aging time,etc. The optimized preparation process of large particle cerium oxide was obtained. The cerium oxide with size between 50 μm to 150 μm was prepared by the process. Moreover,the cerium oxide particles were dispersed uniformly. 相似文献
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氢氧化铈具有无毒的特性,作为铈基功能材料在汽车尾气净化催化剂以及高端电子研磨新材料等领域得到广泛应用,而快速准确地测定氢氧化铈中氧化钾含量对产品的质量控制具有重要意义。氢氧化铈产品中氧化钾质量分数要求不大于0.000 3%,但氧化铈的基体效应干扰氧化钾的测定。实验采用盐酸溶解样品,以草酸分离铈基体,滤液在3%(V/V)的盐酸介质中,以标准加入法绘制工作曲线,建立了空气-乙炔火焰原子吸收光谱法测定氢氧化铈中氧化钾含量的方法。考察了铈基体对钾测定的影响,结果表明,基体铈干扰钾的测定,实验选择在草酸分离大量铈后,采用标准加入法消除草酸基体效应对钾测定的影响。方法检出限为0.50 μg/g,定量限为2.0 μg/g。干扰试验表明,以标准加入法的校正模式进行氢氧化铈中氧化钾含量的测定,样品中共存元素铝、钙、钠、铁、锰、锌、镁和铅对钾测定的干扰可忽略。方法应用于氢氧化铈实际样品中氧化钾的测定,结果的相对标准偏差(RSD, n=11)小于20%。回收率为95%~103%。 相似文献
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Compared to conventional martensitic wear-resistant steels of the same hardness, high-titanium wear-resistant steels with in situ TiC particles can significantly improve wear resistance. However, micron-sized TiC particles will decrease the toughness of high-titanium wear-resistant steels. Here, in order to improve wear resistance without reducing impact toughness, we incorporate 0.0025% cerium elements into high-titanium wear-resistant steels. Compared with no cerium steel, the steel containing cerium is demonstrating comparable mechanical properties, with the yield strength of 1283 MPa and impact toughness of 35.6 J, and the wear performance of the steel containing cerium is 1.78 times that of the steel with no cerium. The results show that with the addition of cerium the effective grain size of the steel decreases, and yield strength and toughness increase. The addition of cerium can form intermetallic compounds of Ce2O2S, which are used as heterogeneous nuclear particles in TiC to form rare earth composite particles calculated by the 2D mismatch theoretical model of Bramfitt. As the average spacing of the reinforcing phase particles in the steel decreases, the effective grain size of the steel decreases, and the number of reinforcing phase particles increases, the wear resistance of the steel with the addition of cerium is optimized. 相似文献