基于X射线衍射仪的PET晶体高阶衍射效率标定

Calibration of High Order Integral Diffraction Coefficient for X-ray PET Flat Crystal on the Automatic X-ray Diffractometer

基于实验室X射线衍射仪,利用Cu X射线管作为光源,对PET晶体的高阶衍射效率进行标定。通过选取适宜厚度的滤片,控制X射线管电压,抑制Cu Kβ及轫致辐射,将Cu Kα单能化。实验结果表明,在Cu Kα能点,PET晶体的二阶积分衍射效率是一阶的14.36%,三阶积分衍射效率是一阶的4.07%;Cu Kα1最大峰值比,二阶衍射为一阶的7.7%,三阶衍射为一阶的1.3%。该标定方法快速高效、方便灵活,为X射线光谱的定量化测量提供了数据支撑,是同步辐射晶体标定的有力补充。

On the automatic X-ray diffractometer （ XRD） ,based on the stability and precision control of θand 2θ goniometer , special plane crystal holder was made .Bremsstrahlung and Cu Kβline are attenuated for 5 or-ders by 40 μm-thick pure Nickel filter in 15 kilo-voltage and 20mA supply to X -ray Cu tube, X-ray source of Cu target is to be Cu Kαmonochromatic source ,transmission coefficient of Nickel filter is the criterion of Cu Kαmonochromatic source.For X-ray Pentaerythritol（002） crystal,integral diffraction coefficient of 1-3 order diffraction on Cu Kαenergy were calibrated .The results show that the 2nd order and the 3rd order is only 14.36%and 4.07%, the Cu Kα1 intensity ratio of 2nd order and the 3rd order is only 7.7%and 1.3%, comparing the 1st order diffraction.This kind of calibration is efficient and convenient on XRD in common labo-ratory .