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研究了用电流体动力学技术制备的纳米超微粉Ｂｉ的晶格结构特征，利用Ｘ射线衍射技术精确测定了不同晶粒尺寸的纳米超微粉Ｂｉ的点阵参数ａ和ｃ．结果表明，纳米超微粉Ｂｉ中的点阵参数ａ和ｃ均小于完整单晶Ｂｉ的点阵参数ａ０和ｃ０，且点阵参数ａ和ｃ及晶胞体积Ｖ均随着晶粒尺寸的减小而减小，而点阵参数ｃ的变化较大．用快速凝固机制解释了纳米超微粉Ｂｉ中的晶格收缩．
The lattice structure of nanometer ultrafine powder Bi prepared by electrokinetic hydrodynamics was studied. The lattice parameters a and c of ultrafine nanometer powders Bi with different grain sizes were accurately determined by X-ray diffraction. The results show that the lattice parameters a and c in nanometer ultrafine powder Bi are smaller than the lattice parameters a0 and c0 of the complete single crystal Bi, and the lattice parameters a and c and the unit cell volume V both decrease with the decrease of the grain size But decreases, while the lattice parameter c changes a lot. The rapid solidification mechanism is used to explain the lattice shrinkage in the nanometer ultrafine powder Bi.