摘要
针铁矿脱水得到赤铁矿,后者的X射线衍射图上,有两组显著不同的衍射线:一组是比较尖锐的,它的宽度变化主要依赖于相变过程中氧离子的重排;另一组是宽散的,它的宽度变化和相变过程中铁离子的迁移重排有关.本文详细研究了这两组衍射线的βcosθ/λ～sinθ/λ曲线,讨论了由它得出的平均晶粒大小(?)和点阵畸变|Δd/d|.在数据处理中本文提出两个拟合公式以替代Jones的校正曲线.此外,在电镜照片中发现250℃脱水产物的表面出现S形裂缝.作者从针铁矿的结构对此现象进行了讨论.
In the X-ray powder diffraction patterns of hematite, formed by the dehydration of goethite, there are two markedly different groups of diffraction lines. One is comparatively sharp, whilst the other is rather diffuse. For the former, the line broadening effect is mainly dependent on the rearrangement of the oxygen Ions during phase change. For the latter, broadening of the line is related to the migration and rearrangement of the ferric ions. The present paper discusses in detail the βcosθ/λ~sinθ/λ curves of these two groups of diffraction lines, the meancrystallite size (-D), and the lattice deformationIn the data treatment, twoformulae are proposed to replace Jones' corrected curves for the facilitation of computerisation.Furthermore, on the surface of the dehydration product at 250℃, S-shaped fractures are observed by the electron microscope. The origin of this phenomenon is diScussed from the structural view of goethite.
出处
《应用科学学报》
CAS
CSCD
1990年第1期55-60,共6页
Journal of Applied Sciences
