[1] CNR, Ist Fotochim & Radiaz Alta Energia, I-40129 Bologna, Italy
[2] Zhejiang Univ, Dept Polymer Sci & Engn, Hangzhou 310027, Peoples R China
[3] Dipartimento Sci Mat, I-26126 Milan, Italy
[4] Zhejiang Univ, Dept Informat & Elect Engn, Hangzhou 31027, Peoples R China