排序方式: 共有24条查询结果,搜索用时 15 毫秒
2.
3.
Thethermaldecompositionofbastnaesitecalcinedinairatmospherewasoneofthepre treatmentstepinhydrometallurgyandpyromet allurgy[1,2 ] .Theinfluenceofdecompositiontemperatureandatmosphereonthedecomposi tionproductswasinvestigatedbyXiangetal[3~ 5 ] .Thermalanalysist… 相似文献
4.
利用X射线衍射、扫描电镜和电子探针等分析手段对碳热还原法稀土硅铁合金的物相及显微组织进行了分析,合金中的主要物相为Si,RESi2和FeSi2;对合金中的单质硅薄带网状结构,RE-Si2与Si和RESi2与FeSi2两类共晶组织进行了较为详细的讨论,这三种组织形成了合金稳定的结构。同时对合金中的主要杂质元素Ca,Al和Ba的存在形式进行了初步鉴定,Ca主要以固溶态的形式存在,Al和Ba主要以化合物形式存在。在此基础上说明了显微组织结构对合金性能的影响。 相似文献
5.
用非稳态热线法测定了碳热法生产稀土硅化物合金原料的导热系数 ,用激光脉冲法测定了稀土硅化物合金的导热系数、热扩散系数和比热容。在 2 88~ 1 573K内 ,原料的导热系数与温度的关系可表示为 :λ =2 .56×1 0 - 2 7.8× 1 0 - 4 T(W·m- 1 ·K- 1 ) ;在 2 88~ 1 2 73K内 ,稀土合金的导热系数与温度的关系可表示为 :λ =1 4.30- 7.4× 1 0 - 3 T(W·m- 1 ·K- 1 )。还测定了原料中两种稀土配碳团块在 773K和 1 2 73K焙烧后的电阻率。 相似文献
6.
7.
8.
9.
10.
The
decomposition products of bastnasite calcined at different temperatures were analysized by
XRD method. Also the decomposition mechanism was discussed. It is concluded that the
decomposition procedure of the bastnasite is separated into several steps. At first, it is
decomposed into (Ce,La)OF. When the calcination temperature increasing, the (Ce,La)OF is
farther decomposed into Ce0.25Nd0.75O1.875 and (Ce,Pr)La2O3F3.
The (Ce,Pr)La2O3F3 can also be decomposed into LaF3、
PrO1.83 and Ce2O3 with temperature increased. After
calcination, Ce3+ and Pr3+ are oxidized into Ce4+ and Pr4+,
but the content of fluorine of products is almost the same as crude material. 相似文献