Gajjar Parmesh, Jørgensen Jakob S, Godinho Jose R A, Johnson Chris G, Ramsey Andrew, Withers Philip J
Henry Moseley X-Ray Imaging Facility, School of Materials, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.
School of Mathematics, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.
Rev Sci Instrum. 2018 Sep;89(9):093702. doi: 10.1063/1.5044393.
Temporal micro-computed tomography (CT) allows the non-destructive quantification of processes that are evolving over time in 3D. Despite the increasing popularity of temporal CT, the practical implementation and optimisation can be difficult. Here, we present new software protocols that enable temporal CT using commercial laboratory CT systems. The first protocol drastically reduces the need for periodic intervention when making time-lapse experiments, allowing a large number of tomograms to be collected automatically. The automated scanning at regular intervals needed for uninterrupted time-lapse CT is demonstrated by analysing the germination of a mung bean (), whilst the synchronisation with an rig required for interrupted time-lapse CT is highlighted using a shear cell to observe granular segregation. The second protocol uses golden-ratio angular sampling with an iterative reconstruction scheme and allows the number of projections in a reconstruction to be changed as sample evolution occurs. This overcomes the limitation of the need to know what the best time window for each scan is. The protocol is evaluated by studying barite precipitation within a porous column, allowing a comparison of spatial and temporal resolution of reconstructions with different numbers of projections. Both of the protocols presented here have great potential for wider application, including, but not limited to, mechanical testing, following battery degradation and chemical reactions.
时间分辨微型计算机断层扫描（CT）能够对随时间三维演变的过程进行无损定量分析。尽管时间分辨CT越来越受欢迎，但实际实施和优化可能具有挑战性。在此，我们介绍了使用商业实验室CT系统进行时间分辨CT的新软件协议。第一个协议极大地减少了在进行延时实验时定期干预的需求，从而能够自动收集大量断层图像。通过分析绿豆的发芽过程，展示了连续延时CT所需的定期自动扫描，同时使用剪切池观察颗粒分离，突出了与中断延时CT所需的装置同步。第二个协议采用黄金分割角采样和迭代重建方案，并允许在样本演变时改变重建中的投影数量。这克服了需要知道每次扫描最佳时间窗口的限制。通过研究多孔柱内重晶石沉淀对该协议进行评估，从而能够比较不同投影数量重建的空间和时间分辨率。这里介绍的这两种协议都具有广泛应用的巨大潜力，包括但不限于机械测试、跟踪电池降解和化学反应。
