1. Department of Colloid Chemistry, St. Petersburg State University, Universitetsky Pr. 26, St. Petersburg 198504, Russia
2. Chemical Engineering Department, National Taiwan University of Science and Technology, 43 Keelung Road, Section 4, Taipei 106, Taiwan
3. Institute of Condensed Matter Physics, Technische Universität Darmstadt, Darmstadt D-64289, Germany