1. Department of Civil, Environmental and Natural Resources Engineering, Chemistry of InterfacesLuleå University of Technology SE-97187 Luleå Sweden
2. NMR Research UnitUniversity of Oulu P.O. Box 3000, FI-90014 Oulu Finland
3. Department Chemical SciencesTezpur University Tezpur 784028 India
4. Department of PhysicsWarwick University CV4 7AL Coventry U.K.