1. Appliances Company, Panasonic Corporation, Yagumo-naka-machi 3-1-1, Moriguchi 570-8501, Japan
2. Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Kofu 400-8511, Japan
3. Fuel Cell Nanomaterials Center, University of Yamanashi, Kofu 400-0021, Japan