X-ray scattering, Physics lectures, Walking in Wales etc.
Photo: PCG-SCMP Rietveld School, Durham University
March 2012 - Morgan attended a four-day course on Rietveld refinement of x-ray diffractograms at Durham University. The school is organised by John and Ivana Evans and is a regular feature in the British Crystallography Association's annual programme. It covers the theory of Rietveld refinement as well as practical aspects using the Topas software. [more 
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In an experiment at Bessy's Eddi beamline, we used energy-dispersive x-ray diffraction to study strain in thin ceramic films, including buried ones. The samples have been produced during an earlier in-situ GISAXS experiment, and it is expected that the films are under strain due to the shrinkage of the coating during calcination. [more] [beamtimes]
This section of the Condensed Matter module covers the different ways of describing the structure of solids: crystal lattices and coordination polyhedra. Diffraction techniques are used to study crystal structures and their imperfections. In the magnetism section, dia-, para- and ferromagnetic states and the transitions between them are compared. Other collective phenomena in solids such as superconductivity and ferroelectricity are also covered. There is also a practical x-ray diffraction workshop included in this module. [more] [teaching]
The morphology of sol–gel derived dip-coated yttria-doped zirconia films containing variable amounts of yttria has been studied using in situ grazing-incidence small-angle X-ray scattering (GISAXS) whilst heated incrementally to 1000C. A procedure to analyse in situ GISAXS data has been devised which allows a quantitative analysis of time-dependent GISAXS data tracing processes such as chemical reactions or manufacturing procedures. To achieve this, the relative positions of the Yoneda peak and the through beam are used to fix the vertical q scale when the sample thickness is subject to fluctuations due to chemical reactions or deposition processes. A version of Beaucage's unified model with a structure factor from Hosemann's model for paracrystals describes the yttria-zirconia film data best. It is interpreted in terms of particles forming from a polymeric gel network and subsequently agglomerating into larger units subject to Ostwald ripening as both size and average separation distance of the scattering objects increase. The sample with the highest yttria content shows progressive surface roughening from 850C which may indicate the onset of chemical segregation. [request reprint] [papers]
Probably mostly of interest to Geograph contributors, this map overlay using maps from the Ordnance Survey OpenSpace project, shows a 100m grid superimposed on zoomable mapping. Helps photographing every nook and cranny of these isles... [more] [other diversions]
Blame me, not my employer etc. etc.