1. Institute of Particle Science and Engineering, School of Process, Environmental and Materials Engineering, University of Leeds, LS2 9JT, U.K., Centre for Process Analytics and Control Technology, School of Chemical Engineering and Advanced Materials, University of Newcastle upon Tyne, NE1 7RU, U.K., and Bede X-ray Metrology, Belmont Business Park, Durham, DH1 1TW, U.K.