1. Key Laboratory of Colloid and Interface Chemistry and; Key Laboratory of Special Aggregated Materials, Ministry of Education; Shandong University; Jinan 250100 Shandong Province P. R. China
2. Department IX, Institute of Physical Chemistry; Polish Academy of Sciences; Warsaw 01-224 Poland
3. State Key Laboratory of Solid Lubrication; Lanzhou Institute of Chemical Physics; Chinese Academy of Sciences; Lanzhou 730000 Gansu Province P. R. China