1. Department
of Chemical and Biochemcial Engineering, Danish Polymer Center, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
2. Niels
Bohr Institute, X-ray and Neutron Science, University of Copenhagen, DK-2100 København Ø, Denmark
3. School
of Mathematical Sciences, University of Nottingham, Nottingham NG7 2RD, U.K.