Project

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High-resolution quantitative local X-ray phase tomography

Applicant Bunk Oliver
Number 137772
Funding scheme Project funding (Div. I-III)
Research institution Paul Scherrer Institut
Institution of higher education Paul Scherrer Institute - PSI
Main discipline Other disciplines of Physics
Start/End 01.04.2013 - 31.03.2015
Approved amount 195'490.00
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Keywords (2)

Computer-Tomographie; Phasenkontrast

Lay Summary (German)

Lead
Hochauflösende, quantitative inwendige Röntgentomographie
Lay summary
Dreidimensionale Abbildungen mit Hilfe von Röntgenphasenkontrast können Dichteunterschiede deutlich unter dem Prozentbereich und Auflösung unterhalb von 100 Nanometer in jede Raumrichtung erzielen. Für Studien an im Vergleich zur Auflösung grossen Proben im Bereich von einer Million Kubikmikrometern müssen hochauflösende Übersichtsmessungen mit lokalen Messungen inwendiger Details in hoher Auflösung kombiniert werden. Derartige Messungen mit quantitativem Dichtekontrast würden einen grossen Fortschritt für die Lebens- und Materialwissenschaften darstellen.

In diesem Projekt soll Rasterröntgenmikroskopie mit einem zweidimensionalen Detektor im Phasenkontrastmodus für Übersichtsmessungen genutzt und mit ptychographisch kohärenter Röntgenbeugung für lokal hochaufgelöste Messungen verbunden werden. Diese Kombination wird eine intuitive Arbeitsweise erlauben, in der in der Übersichtsabbildung interessante Bereiche identifiziert werden, die anschliessend hochaufgelöst vermessen werden. Das Besondere an dieser Kombination ist, dass durch die Verbindung mit der Übersichtsmessung auch die lokale Messung quantitative Ergebnisse liefert.
Direct link to Lay Summary Last update: 31.01.2013

Responsible applicant and co-applicants

Employees

Name Institute

Publications

Publication
Assessment of the 3D Pore Structure and Individual Components of Pre-Shaped Catalyst Bodies by X-Ray Imaging.
da Silva Julio Cesar, Mader Kevin, Holler Mirko, Haberthür David, Diaz Ana, Guizar-Sicairos Manuel, Cheng Wu-Cheng, Shu Yuying, Raabe Jörg, Menzel Andreas, van Bokhoven Jeroen Anton (2015), Assessment of the 3D Pore Structure and Individual Components of Pre-Shaped Catalyst Bodies by X-Ray Imaging., in ChemCatChem, 7(3), 413-416.
Quantitative interior X-ray nanotomography by a hybrid imaging technique
Guizar-Sicairos Manuel, Boon Jaap J., Mader Kevin, Diaz Ana, Menzel Andreas, Bunk Oliver (2015), Quantitative interior X-ray nanotomography by a hybrid imaging technique, in Optica, 2(3), 259-266.
Mass Density and Water Content of Saturated Never-Dried Calcium Silicate Hydrates
da Silva Julio C, Trtik Pavel, Diaz Ana, Holler Mirko, Guizar-Sicairos Manuel, Raabe Jörg, Bunk Oliver, Menzel Andreas, Mass Density and Water Content of Saturated Never-Dried Calcium Silicate Hydrates, in Langmuir.

Collaboration

Group / person Country
Types of collaboration
Prof. J. Boon, FOM Institute AMOLF Netherlands (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
- Industry/business/other use-inspired collaboration
Prof. P. Trtik, laboratory for concrete and construction chemistry, EMPA Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Industry/business/other use-inspired collaboration

Associated projects

Number Title Start Funding scheme
152554 Ptychography with extended depth of field for tomography applications 01.01.2015 Project funding (Div. I-III)
175905 Three-dimensional elemental mapping on the nanoscale combining X-ray fluorescence and ptychographic tomography 01.07.2018 Project funding (Div. I-III)
145056 OMNY (tOMography, Nano, crYo stage) 01.01.2013 R'EQUIP
147172 Micro- and nanoanatomy of human brain tissues 01.09.2013 Interdisciplinary projects
166304 X-Ray Fourier Ptychography 01.04.2016 Project funding (Div. I-III)

Abstract

This document describes a proposal for a two-year research project to be funded by the Swiss National Science Foundation. It details the continuing development of quantitative phase tomography with high specificity, i.e., sensitive to density variations well below the percent level, and high resolution, i.e., resolving details = 100nm in size. In order to survey significant sample volumes, e.g., in the (100 µm)3 range, high-resolution local tomography shall be complemented with low-resolution overview tomography with micron resolution. Such imaging capabilities will open new avenues in both life and materials sciences. As specific examples, we will discuss research on nanoporous materials like bone, cement, and avian eggshell; the quantitative determination of mass densities is of paramount importance in both basic and applied bone research, colloid science, and studies of composite materials. To pursue methodological development necessary to offer a tomographic characterization technique with the desired resolution and sensitivity, we ask for funding of a PostDoc position over the period of two years.X-ray phase imaging has undergone rapid developments in recent years. Imaging the phase advance of X-ray radiation allows a reliable quantitative determination of the electron density of the sample and employs a contrast channel that does not depend on absorption, which is inherently linked to radiation damage. While macroscopic phase imaging techniques like holo-tomography, grating interferometry, and Zernike phase contrast can yield sub-micron resolution, the combination of high resolving power and quantitativeness remains challenging and places stringent demands on both experimental conditions and, more crucially, on the samples that can be investigated. Techniques like coherent diffractive imaging offer high resolution but quantitative analysis is challenging as well. Particularly, high dose requirements and the limitation to isolated samples of only a few microns in size have drastically limited its applicability for scientific surveys. Ptychographic coherent diffractive imaging, a technique that allows high-resolution phase tomography of samples tens of microns in diameter, has been developed at the Paul Scherrer Institute and is by now routinely used at the Swiss Light Source.We propose to extend the capabilities of this technique to larger samples, mitigating sample preparation, minimizing preparation-caused artifacts, and facilitating surveys of scientifically significant sample volumes and numbers. To this task we plan to combine scanning transmission X-ray microscopy with high-resolution quantitative phase tomography on selected areas of interest. Micron resolution shall suffice for the low-resolution scans that will allow fast surveys of volumes in the 100 micron range and beyond and thus will enable the experimenter to identify regions of interest for subsequent high-resolution measurements. Furthermore, this low-resolution scan will yield information important for the quantitative analysis of local high-resolution tomograms. To facilitate local tomography with sub-100 nm resolution we plan to use nonlinear optimization for the alignment of individual projection images prior to reconstruction of the 3D data set. Phase wrapping and phase offsets, inherent issues in many phase imaging modalities, are addressed by using a 3D reconstruction filter operating on differential phase contrast data. The algorithms developed for the analysis of high-resolution local phase tomography data will be of general applicability in 3D imaging, especially at sub-micron resolution where mechanical limitations in sample positioning starts to degrade imaging resolution if unaccounted for.Several research projects currently pursued with Swiss and international collaborators will immediately benefit from these developments. As examples we mention investigations of bio-nanoporous materials like bone and avian eggshell, as well as cement research as a materials science application.
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