Search results for "Nanotomography"
showing 4 items of 4 documents
The pore structure of compacted and partly saturated MX-80 bentonite at different dry densities
2014
Compacted MX-80 bentonite is a potential backfill material in radioactive-waste repositories. Pore space in MX-80 has been the subject of considerable debate. 3D reconstructions of the pore space based on tomographic methods could provide new insights into the nature of the pore space of compacted bentonites. To date, few such reconstructions have been done because of problems with the preparation of bentonite samples for electron microscopy. The nanoscale intergranular pore space was investigated here by cryo-Focused Ion Beam nanotomography (FIB-nt) applied to previously high-pressure frozen MX-80 bentonite samples. This approach allowed a tomographic investigation of the in situ microstru…
Publisher Correction: X-Ray Nanotomography of Individual Pulp Fibre Bonds Reveals the Effect of Wall Thickness on Contact Area
2020
Fibre bonds play an essential role in various properties of paper. Much research has focused on their strength, but the determination of the actual contact area also provides a challenge. Many of the research methods rely on optical tools, which are restricted by the wavelength of light that is utilised. Novel X-ray computed tomography devices utilise X-rays in studying the inner structure of materials, and surpass the optical methods in terms of resolution, allowing detection of even smaller details and variations in distance between the fibres in the bond intersection area. X-ray nanotomography was used to image 26 individual cellulose fibre bonds made of springwood and summerwood fibres …
X-ray nanotomography and electron backscatter diffraction demonstrate the crystalline, heterogeneous and impermeable nature of conodont white matter
2021
Conodont elements, microfossil remains of extinct primitive vertebrates, are commonly exploited as mineral archives of ocean chemistry, yielding fundamental insights into the palaeotemperature and chemical composition of past oceans. Geochemical assays have been traditionally focused on the so-called lamellar and white matter crown tissues; however, the porosity and crystallographic nature of the white matter and its inferred permeability are disputed, raising concerns over its suitability as a geochemical archive. Here, we constrain the characteristics of this tissue and address conflicting interpretations using ptychographic X-ray-computed tomography (PXCT), pore network analysis, synchro…
Improving methods in X-ray nanotomography of fibre bonds
2017
X-ray nanotomography has proven to be a useful yet challenging method in the study of cellulose fibre bonds. The challenges encountered in previous researches are related to lengthy imaging times and low success rate per sample. To counter these obstacles, fibre staining in order to enhance contrast in radiographic images and an alternative method for marker particle placement were examined in this study. Cesium iodide proved to be a suitable staining material, and the alternative method for particle placement may increase success rate by reducing microfibril structure fracturing during the marker placement process.