1. State
Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
2. Research Center
for Radiation Protection, National Institute of Radiological Sciences, Chiba 263-8555, Japan
3. State
Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China
4. Institute
of Radiation Emergency Medicine Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan