The quantitative Rietveld analyses of twenty samples of CAC from four different manufacturers over the world, one synthetic mixture and a NIST standard were performed using synchrotron radiation. As compared with conventional XRD, synchrotron powder diffraction permitted to find new minor phases, improve the characterization of solid solutions of iron rich CAC phases and reduce preferential ori...

This is the fourth in a series of papers on Rietveld materials characterisation metrology presented at recent Denver X-ray Conferences [refs 1-3]. Reference 3 examined the management of the zero-point and specimen displacement corrections in extracting lattice parameters from BraggBrentano x-ray diffraction data by Rietveld analysis. This paper emphasises the importance of pre-determining the z...

Nanoscale potassium niobate (KNbO3) powders of orthorhombic structure were synthesized using the sol-gel method. The heat-treatment temperature of the gels had a pronounced effect on KNbO3 particle size and morphology. Field emission scanning electron microscopy and transmission electron microscopy were used to determine particle size and morphology. The average KNbO3 grain size was estimated t...

In chapter 10 migration is described in terms of double focussing. In chapter 11 focussing in emission is used to synthesize common focus point gathers (CFP gathers). By comparing aCFPgather with its related focussing operator velocity errors can be detected and the focussing operator can be corrected (Berkhout and Rietveld (1994), Rietveld and Berkhout (1994) , Berkhout (1992), Rietveld and Th...

2139., [2] International Centre for Diffraction Data, Newtown Square, PA 19073-3273 U.S.A., [3] Von Dreele R.B. (2000) 49 Denver X-ray Conference, Colorado, [4] The Rietveld Method, Ed. R.A. Young (1993) International Union of Crystallography, Oxford University Press) 4 5 6 7 8 2θ, deg In te ns ity ( c /s ) L D Lunar and Planetary Science XXXIV (2003) 1682.pdf