1. Contribution from the Department of Radiation, Radionuclides and Reactors, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629JB Delft, The Netherlands, the Institut de recherche sur l'hydrogène, Université du Québec à Trois-Rivières, (Qc)G9A 5H7 Canada, the ISIS facility, Rutherford Appleton Laboratory, Chilton, Didcot, United Kingdom, and the National Centre for HREM, Delft University of Technology, The Netherlands