[1] Fdn Res & Technol Hellas, Inst Elect Struct & Laser, POB 1385, GR-71110 Iraklion, Crete, Greece
[2] Cornell Univ, Dept Mat Sci, Ithaca, NY 14853 USA
[3] Univ Thessaloniki, Dept Chem Engn, Thessaloniki GR-54124, Greece
[4] Univ Crete, Mat Sci & Technol Dept, Iraklion GR-71103, Greece