1. Department of Energy and Process Engineering, Norwegian University of Science and Technology, Trondheim 7034, Norway, Institute of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences, Post Office Box 17, Budapest 1525, Hungary, and Chemische Verfahrenstechnik, Rheinisch-Westfälische Technische Hochschule Aachen, Turmstrasse 46, Aachen 52064, Germany