1. Arnold and Mabel Beckman Laboratories for Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
2. Institute of Chemical and Engineering Sciences, 1 Pesek Road, Jurong Island, Singapore 627833.
3. Visiting Chair Professor at King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia 31261.