Visualising Geopolymerisation Processes Using Scanning X-Ray Diffraction and Fluorescence Microscopy.

In situ observation of the dissolution of metakaolin followed by the condensation of geopolymer was performed by a combination of synchrotron X-ray fluorescence microscopy and scanning X-ray diffraction microscopy. New insight into the complex geopolymerisation process was obtained by simultaneously acquiring compositional and morphological information. The combination of selected alkali and experimental conditions produced a geopolymer with the targeted composition but resulted in the complete and rapid dissolution of metakaolin followed by immediate geopolymer formation.

Dynamic X-ray Coherent Diffraction Analysis: Bridging the Time Scales between Imaging and Photon Correlation Spectroscopy.

The advent of diffraction limited sources and developments in detector technology opens up new possibilities for the study of materials and . Coherent X-ray diffraction techniques such as coherent X-ray diffractive imaging (CXDI) and X-ray photon correlation spectroscopy (XPCS) are capable for this purpose and provide complementary information, although due to signal-to-noise requirements, their simultaneous demonstration has been limited. Here, we demonstrate a strategy for the simultaneous use of CXDI and XPCS to study the Brownian motion of colloidal gold nanoparticles of 200 nm diameter suspended in a glycerol-water mixture.

Towards kilohertz synchrotron coherent diffractive imaging.

X-ray coherent diffractive imaging (CDI) techniques have been applied with widespread impact to study nanoscale material properties. New fast framing detectors may reveal dynamics that occur at millisecond timescales. This work demonstrates by simulation that kilohertz synchrotron CDI is possible, by making use of redundant information from static parts of the image field.

High-speed free-run ptychography at the Australian Synchrotron.

Over the last decade ptychography has progressed rapidly from a specialist ultramicroscopy technique into a mature method accessible to non-expert users. However, to improve scientific value ptychography data must reconstruct reliably, with high image quality and at no cost to other correlative methods. Presented here is the implementation of high-speed ptychography used at the Australian Synchrotron on the XFM beamline, which includes a free-run data collection mode where dead time is eliminated and the scan time is optimized.

Dynamic coherent diffractive imaging using unsupervised identification of spatiotemporal constraints.

Dynamic coherent diffractive imaging (CDI) reveals the fine details of structural, chemical, and biological processes occurring at the nanoscale but imposes strict constraints on the object distribution and illumination. Ptychographic CDI relaxes these constraints by exploiting redundant information in data obtained from overlapping regions of an object, but its time resolution is inherently limited. We have extended ptychographic redundancy into the spatiotemporal domain in dynamic CDI, automatically identifying redundant information in time-series coherent diffraction data obtained from dynamic systems.