1. Cyclotron Research Center, Iwate Medical University, Tomegamori, 020-01 Takizawa, Japan
2. Nishina Memorial Cyclotron Center, Japan Radioisotope Association, Tomegamori, 020-01 Takizawa, Japan
3. Akita Prefectural Institute of Environmental Science, 191-18, Shimoyabase-yabase, 010 Akita, Japan