1. Department of Mechanical and Materials Engineering University of Western Ontario London Ontario N6A 6B9 Canada
2. Department of Materials Science and Engineering McMaster University Hamilton ON L8S 4L8 Canada
3. Canadian Light Source Saskatoon SK S7N 2V3 Canada
4. College of Materials Sciences and Engineering Key Laboratory of Advanced Functional Materials Education Ministry of China Beijing University of Technology Beijing 100124 P. R. China
5. Department of Chemistry University of Western Ontario London Ontario N6A 5B7 Canada
6. General Motors Research & Development Center Warren MI 48090-9055 USA