Sample layout aiding efficient scans of heterogeneous sheet-like materials

3D image of a sample layout that enables a more efficient structure acquisition of heterogeneous sheet-like materials like paper with X-ray computed microscopy.[1] Sheets are very thin compared to their lateral extension, e.g., paper sheets consisting of cellulose-based fibers. Local variations in the pore space might be considerably further apart than the sheet is thick. Hence, air or liquids transported through such sheets might experience locally different bottlenecks, for example, due to a reduced porosity or more torturous pathways. To quantify the number and properties of such bottlenecks it is necessary to probe many locations in the sheets while keeping a resolution large enough to resolve the pore space. Probing the sheet location by location using X-ray computed microscopy is highly time-consuming. The key idea of our sample layout is to permit the scan of multiple cutouts from the sheet at once. From the bottom to the top, the artistically enhanced image reveals the essential arrangement of the cutouts alike a peeled-off banana. Four paper strips, highlighted in color, are arranged into a stack. In this stack of paper strips, Kapton strips are intercalated as spacers (shown as upright grey sheets of alternating thickness in the image center). The resulting stack sits tightly fitted in a Kapton tube (grey cylinder at the bottom).
All such acquired cutouts combined inform on local sheet variations on the centimeter scale.

[1] Neumann M. and Machado Charry, E. and Baikova, E. and Hilger, A., Hirn, U. and Schennach, R. and Manke, I., Schmidt, V. and Zojer, K., Capturing centimeter-scale local variations in paper pore space via micro-CT: A benchmark study using calendered paper, Microscopy and Microanalysis, 2021 doi:10.1017/S1431927621012563}.