[1] Univ Yamanashi, Interdisciplinary Grad Sch Med & Engn, 4 Takeda, Kofu, Yamanashi 4008510, Japan
[2] Daihatsu Motor Co Ltd, Frontier Technol R&D Div, 3000 Ryuo, Shiga 5202593, Japan
[3] Univ Yamanashi, Clean Energy Res Ctr, 4 Takeda, Kofu, Yamanashi 4008510, Japan
[4] Univ Yamanashi, Fuel Cell Nanomat Ctr, 4 Takeda, Kofu, Yamanashi 4008510, Japan