BUNSEKI KAGAKU Vol. 66, No. 3, pp. 175 180 2017 2017 The Japan Society for Analytical Chemistry 175 1,5 1 2 3 4 134 Cs, 137 Cs 2011 137 Cs Fe, Mn 137 Cs 1 Fukushima Daiichi Nuclear Power Plant, FDNPP 5 134 Cs, 137 Cs FDNPP 250 km 1 17 3960 Bq kg 1 137 Cs : 30 FDNPP 200 300 km E-mail : koi@meiji.ac.jp 1 : 214-8571 1-1-1 2 : 214-8571 1-1-1 3 : 569-1146 14-8 4 : 214-8571 1-1-1 5 : 975-0036 45-169 2011 1200 m 2 : 1400 m 3 FDNPP FDNPP 2004 2011 2 2013 5 2016 γ Tessier 4 2 2 1
176 B U N S E K I K A G A K U Vol. 66 2017 6 7 7 137 Cs 3 g 137 Cs HPGe γ Fig. 1 Sampling locations in this study : Topography is based on ROOTS PRO Japan (HEIBONSHA. C. P. C.). 5 cm Fig. 1 FDNPP 240 km 2004 4 11 2011 10 12 2013 4 9 2016 9 5 2011 8 9 2016 8 11 2004 5 2 2 110 24 2 mm U-8 U-8 ; : 55 mmh : 48 mmφ 50 mm 100 mm 5 mm 5 mm Ge HPGe; PGT, Inc. IGC-10200 NPR γ 134 Cs 604.7 kev 137 Cs 661.7 kev γ JSAC 0471 2 3 IE CB Fe, Mn OX OB RES 2 4 X X Rigaku Smart Lab 1 X D/teX Ultra 250 Cu X 45 kv 200 ma 2 mm CMT TI-100 5 100 /2θ 3 min 1 0.01 1/6 20 mm 2.5 120 rpm 3 X PDXL 3 3 1 2004 2016 γ Fig. 2 FDNPP 2004 134 Cs FDNPP 2011 134 Cs 134 Cs 137 Cs 2004 134 Cs 137 Cs 8 Fig. 3 Fig. 3 134 Cs/ 137 Cs FDNPP 2011 3 15 9 1
: 177 Fig. 2 Gamma - ray spectra of soil sampled in Kawasaki A) 11, Apr. 2004, B) 12, Oct. 2011, C) 9, Apr. 2013, D) 5, Sep., 2016. 10 11 137 Cs 134 Cs 2013 137 Cs 12 5 2016 147 Bq kg 1 134 Cs 137 Cs 3 2 137 Cs 137 Cs Fig. 4 137 Cs 100 101 2011 2013 2016 137 Cs OX RES 25 OX 75 RES OX Fe, Mn RES 4 137 Cs IE CB OB OX RES 5 RES Fig. 3 Activity concentrations and ratios of radiocesium in soil sampled in Kawasaki : Activity concentrations of radiocesium in soil sampled after the FDNPP accident have been corrected to the sampling date. : Activity ratios of radiocesium in soil sampled after the FDNPP accident have been corrected to the 15, Mar. 2011., 134 Cs;, 137 Cs;, Activity ratio ( 134 Cs/ 137 Cs). Fig. 4 Chemical form of 137 Cs in soil sampled in Kawasaki, OX;, RES. 3 3 137 Cs 2011 2016 2011 3 15 9 134 Cs/ 137 Cs Table 1 1 Terada 13 Worldwide version of System for Prediction of Environmental Emergency Dose Information, W-SPEEDI 100 Fig. 1 FDNPP : 2145 m : 2956 m :
178 B U N S E K I K A G A K U Vol. 66 2017 Table 1 Activity concentrations and ratios of radiocesium in soil sampled in Kawasaki and Nakano Sampling area Sampling Year Activity concentration ( 1σ) /Bq kg 1 134 Cs 137 Cs 134 Cs/ 137 Cs Kawasaki 2011 137 7 198 4 0.83 0.05 2016 25 1 163 2 0.85 0.03 Nakano 2011 36 2 44 1 0.94 0.07 2016 12 0.4 77 1 0.86 0.04 : Activity concentrations of radiocesium in soil sampled after the FDNPP accident have been corrected to the sampling date. : Activity ratios of radiocesium in soil sampled after the FDNPP accident have been corrected to 15, Mar. 2011. Fig. 5 Activity of 137 Cs in 3 g of soil sampled in Kawasaki and Nakano in 2016, OX;, RES. 2171 m 2011 3 15 21 Terada 13 2 137 Cs 2016 137 Cs Fig. 5 137 Cs OX 25 RES 75 137 Cs OX 90 RES 10 OX RES X X Fig. 6 Fig. 6 X-ray diffraction patterns of soil sampled in Kawasaki and Nakano A) Kawasaki, B) Nakano. Bi, Biotite; Cal, Calcite; Chl, Chlorite; Mg, Magnetite; Mus, Muscovite; Pl, Plagioclase; Qtz, Quartz. 14 15 2011 5 2016 4 FDNPP FDNPP 5
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180 B U N S E K I K A G A K U Vol. 66 2017 Characterization of Radiocesium in Soil Sampled at the Koshinetsu and Kanto Regions Kotaro OCHI 1,5, Kengo FUJII 1, Kenta HAGIWARA 2, Atsushi OHBUCHI 3 and Yuya KOIKE 4 E-mail : koi@meiji.ac.jp 1 Applied Chemistry Course, Graduate School of Science and Technology, Meiji University, 1-1-1, Higashimita, Tama-ku, Kawasaki-shi, Kanagawa 214-8571 2 Organization for the Strategic Coordination of Research and Intellectual Properties, Meiji University, 1-1-1, Higashimita, Tama-ku, Kawasaki-shi, Kanagawa 214-8571 3 X-ray Instrumental Division, Rigaku Corporation, 14-8, Akaoji, Takatsuki-shi, Osaka 569-1146 4 Department of Applied Chemistry, School of Science and Technology, Meiji University, 1-1-1, Higashimita, Tama-ku, Kawasaki-shi, Kanagawa 214-8571 5 Current Address: Fukushima Environmental Safety Center, Sector of Fukushima Research and Development, Japan Atomic Energy Agency, 45-169, Sukakeba, Kaibama, Haramachi-ku, Minamisoma-shi, Fukushima 975-0036 (Received October 14, 2016; Accepted January 16, 2017) Fukushima-derived radiocesium ( 134 Cs and 137 Cs) was spread out all over the world after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. After this accident, radiocesium was detected in soil at the Koshinetsu and Kanto regions. In this study, the activity concentration and the chemical forms of radiocesium in soil were analyzed for predicting any long-term effect of radiocesium in soil at low-dose areas. It is revealed that the distribution of radiocesium depends on the kind of clay minerals in soil. During passing years after the FDNPP accident, the activity concentrations of radiocesium in soil were nearly constant because of the insoluble chemical form. It is suggested that radiocesium would be fixed to minerals in soil for a long time. Keywords: Fukushima Daiichi Nuclear Power Plant accident; Radiocesium; Koshinetsu region; Kanto region; chemical form.