研究和开发新型有机功能材料来吸附重金属离子，是解决水体重金属污染的重要途径之一。采用传统技术，很难直接观察到吸附材料中重金属离子的分布。利用同步辐射X射线能量可调谐及其较强的穿透性，采用K边减影(KES)成像技术对此问题进行了研究。通过优化实验条件和图像配准、中值滤波等图像处理，成功地将这一技术运用到有机材料吸附金属离子过程的研究中，得到了非常清晰的铜离子在聚偏氟乙烯改性高分子材料上的分布图像。研究结果表明，铜离子被吸附后进入到吸附材料的内部。通过研究还发现，样品颗粒的尺度对铜离子进入颗粒内部的深度影响不明显，单位时间铜离子吸附的质量主要受到吸附材料表面积的影响。

The investigation and development of novel functional organic material for the adsorption of heavy metal ion in water is one of the important solutions to water pollution. However, with traditional techniques, it is very difficult to observe directly the distribution of heavy metal ion inside the adsorptive material. By means of the tunability and penetrability of the X-rays, this problem is researched with K-edge digital subtraction (KES) imaging. Systematical investigation is carried out successfully, resorting to optimization for experimental conditions, image registration and median filtering etc.. The experimental results demonstrate that the adsorbed copper ions can infiltrate into the adsorber. The results also indicate that sizes of the adsorbing particles do not have obvious impact on the infiltrating depth of the copper ions. The mass of the copper ions adsorbed per unit time is mainly affected by the superficial area.