A generalized quantitative interpretation of dark-field contrast for highly concentrated microsphere suspensions.
A generalized quantitative interpretation of dark-field contrast for highly concentrated microsphere suspensions.
复制标题
DOI：
10.1038/srep35259
复制
发表时间：
2016-10-13
影响因子：
4.6
通讯作者：
Stampanoni M
中科院分区：
文献类型：
--
作者：
Gkoumas S;Villanueva-Perez P;Wang Z;Romano L;Abis M;Stampanoni M
在X射线光栅干涉测量中，由于检测到的干涉条纹的部分消光而产生暗场对比度。这也被称为可见度降低，并且归因于来自成像物体中未分辨结构的小角度散射。近年来，已开发出用于高度稀释的单分散微球悬浮液（最大体积分数为6%）的暗场对比度定量分析框架。这些框架假设散射粒子被足够大的距离分开，这使得任何粒子间散射干扰可以忽略不计。本文从小角散射强度方程出发，通过傅立叶变换和实空间相结合的方法，引入结构因子，对体积分数为40%的悬浮液进行了暗场对比度的定量解释。结构因子解释了粒子间散射干涉。在不引入任何额外的拟合参数的情况下，我们成功地预测了在TOMCAT光束线，瑞士光源测量的实验值。最后，我们将这个理论框架应用到一个实验中，通过在不同能量下获取暗场图像来探测一系列系统相关长度。所提出的方法有可能被应用于单次拍摄模式，使用多色X射线管设置和单光子计数能量分辨探测器。
In X-ray grating interferometry, dark-field contrast arises due to partial extinction of the detected interference fringes. This is also called visibility reduction and is attributed to small-angle scattering from unresolved structures in the imaged object. In recent years, analytical quantitative frameworks of dark-field contrast have been developed for highly diluted monodisperse microsphere suspensions with maximum 6% volume fraction. These frameworks assume that scattering particles are separated by large enough distances, which make any interparticle scattering interference negligible. In this paper, we start from the small-angle scattering intensity equation and, by linking Fourier and real-space, we introduce the structure factor and thus extend the analytical and experimental quantitative interpretation of dark-field contrast, for a range of suspensions with volume fractions reaching 40%. The structure factor accounts for interparticle scattering interference. Without introducing any additional fitting parameters, we successfully predict the experimental values measured at the TOMCAT beamline, Swiss Light Source. Finally, we apply this theoretical framework to an experiment probing a range of system correlation lengths by acquiring dark-field images at different energies. This proposed method has the potential to be applied in single-shot-mode using a polychromatic X-ray tube setup and a single-photon-counting energy-resolving detector.
登录
查看更多内容
影响因子：
5.5
作者：
KINNING, DJ;THOMAS, EL
通讯作者：
THOMAS, EL
影响因子：
4.6
作者：
Sung Y;Segars WP;Pan A;Ando M;Sheppard CJ;Gupta R
通讯作者：
Gupta R
影响因子：
3.5
作者：
Potdevin, Guillaume;Malecki, Andreas;Pfeiffer, Franz
通讯作者：
Pfeiffer, Franz
影响因子：
16.6
作者：
Wang, Zhentian;Hauser, Nik;Stampanoni, Marco
通讯作者：
Stampanoni, Marco
影响因子：
19.6
作者：
Pfeiffer, F;Weitkamp, T;David, C
通讯作者：
David, C