采用吸收修正Bronnikov算法的有机复合样品的X射线显微计算机层析研究

有机复合样品如大多数由低原子序数物质构成的多聚物组合材料、生物软组织等具有混合相位和振幅特性,采用传统吸收计算机层析(CT)或纯相位重构算法难以达到较高密度分辨的目的。采用基于吸收修正的Bronnikov相位恢复算法的X射线同轴相衬CT技术对高分子混合组份材料和药物医学样品进行了实验研究。结果表明该相位恢复算法可以实现多聚物组合材料的无损分辨和精确测量,能够清晰辨别各组份材料的电子密度分布;验证了药物样品多孔性结构三维测量的可行性,能够有效提供孔隙测量的阈值选择。该方法在材料科学尤其是聚合物组合材料、泡沫多孔材料都会发挥很好的作用;单距的低辐射优势,尤其适用于生物医学样品三维无损成像。

Investigation on X-Ray Micro-Computed Tomography Suitable for Organic Compound Samples Based on Modifed Bronnikov Algorithm

Organic compound samples are characterized by mixed phase and amplitude, such as most polymer combination materials and biological soft tissues made from low-atomic-number materials etc, which are very hard to obtain higher resolution of density by conventional absorption computerized tomography (CT) or phase retrival algorithm of pure-phase object. The X-ray in-line phase contrast CT technology based on the modified Bronnikov algorithm has been utilized for the experimental investigation of high polymer mixed materials and medical samples. The experimental results show that the proposed method can realize the non-destructive imaging and precise measurement of polymer combination samples by distinguishing those electronic densities of different parts clearly. In addition, the results demonstrate the feasibility of three-dimensional measurement of medical samples with porosity by supplying with a valid threshold. The method has good potential application in material science, especially in polymers and foam porous materials, and three-dimensional nondestructive imaging of biomedicine due to the advantage of low radiation dose.