Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
-ray spectra measured inside and outside a house in FukushimaTanimura, Yoshihiko; Tomita, Jumpei; Yoshitomi, Hiroshi; Yoshizawa, Michio; Hakozaki, Ryozo*; Takahashi, Sohei*
Hoken Butsuri, 51(3), p.141 - 146, 2016/09
Photon spectra were measured inside and outside a house in Minami-Soma city by using a NaI(Tl) scintillation spectrometer. The photons were categorized into three groups according to their energy. The groups were (1) scattered photons, which include low energy photons, (2) direct photons from 
Cs and 
Cs sources and (3) the other photons. Then the ratios of the ambient dose equivalents H
(10) of the scattered photons to those of the direct photons from the Cs and Cs sources have been evaluated from the measured photon spectra. The ratios are high inside the house compared with those out of the house. It was found that the scattered photons contribute to the H(10) by more than 50
inside the house. The ambient dose equivalent average energies of the scattered photons are around 0.25 MeV both inside and outside the house. These data is worthwhile to design the optimum shielding for the protection against the public radiation exposure.
Takahashi, Nobuo; Yokoyama, Kaoru; Morimoto, Yasuyuki; Shimaike, Masamitsu; Ikegami, Sohei; Sugitsue, Noritake
JAEA-Technology 2010-003, 92 Pages, 2010/06
JAEA-Technology-2010-003.pdf:10.76MB
At the reprocessed uranium conversion facilities, Hydration and Conversion room-1,2,3, Dehydration and Conversion room-1,2, Dry process filter room have been dismantled according to the schedule, in 2009 fiscal year. The -ray measurement had been carried out before dismantlement to evaluate the radioactivity inventory. As a result, the uranium recovery work was forecasted for reasonable dismantlement. In addition, the feature nuclide affecting the results of the measurement on the air dose was evaluated. Additionally, as the waste data, -ray analysis results are shown.
Shimaike, Masamitsu; Yokoyama, Kaoru; Ikegami, Sohei; Takahashi, Nobuo; Sugitsue, Noritake
JAEA-Technology 2009-020, 55 Pages, 2009/06
JAEA-Technology-2009-020.pdf:2.0MB
At the conversion facility, 48Y homogenization treatment equipment (cylinder processing room), UO
pneumatic dispatch equipment (fluoride precipitation process room), gas trapping and filling equipment (cold trap room and UF
filling room) and the second grade UF
drying equipment (UF feed chamber and UF treatment room) are scheduled to be dismantled, in 2008 fiscal year. The -ray measurement intended for the equipment was done before dismantlement and the radioactivity inventory was evaluated. As a result, the part that the uranium recovery had to be executed was forecast for reasonable dismantlement. Additionally, the reprocessed uranium was used at the conversion facility, so the feature nuclide affecting the air dose was evaluated. In addition, -ray analysis results are organized for using as the waste data and the radionuclide distribution data in the process.
Takahashi, Nobuo; Yokoyama, Kaoru; Ikegami, Sohei; Shimaike, Masamitsu; Sugitsue, Noritake
JAEA-Technology 2009-002, 51 Pages, 2009/03
JAEA-Technology-2009-002.pdf:5.71MBJAEA-Technology-2009-002(errata).pdf:0.24MB
At the conversion facility, dismantlement and removal of the equipment are executed according to the decommissioning plan. The radioactivity of the spent bed material discharged along with the reprocessed uranium conversion is high. So, there is concern that the external exposure caused by the dismantlement of the spent bed material storage is high. Therefore, the uranium isotopic analysis using the -ray measurement intended for the spent bed material was done, and the external exposure at site boundary was evaluated. As a result, the external exposure at site boundary is low. The external exposure caused by dismantlement work was evaluated, and the points to remember for dismantlement of the spent bed material storage are considered.
Oshima, Takeshi; Ito, Hisayoshi; Uedono, Akira*; Suzuki, Ryoichi*; Ishida, Yuki*; Takahashi, Tetsuo*; Yoshikawa, Masahito; Kojima, Kazutoshi; Odaira, Toshiyuki*; Nashiyama, Isamu; et al.
Denshi Gijutsu Sogo Kenkyujo Iho, 62(10-11), p.469 - 476, 1999/00
no abstracts in English
Ikegami, Sohei; Tanaka, Yoshio; Tokuyasu, Takashi; Takahashi, Nobuo; Sugitsue, Noritake; Morimoto, Yasuyuki
no journal, ,
no abstracts in English
Shimaike, Masamitsu; Takahashi, Nobuo; Morimoto, Yasuyuki; Ikegami, Sohei; Sugitsue, Noritake
no journal, ,
no abstracts in English
Takahashi, Nobuo; Shimaike, Masamitsu; Morimoto, Yasuyuki; Ikegami, Sohei; Sugitsue, Noritake
no journal, ,
no abstracts in English
Takahashi, Nobuo; Morimoto, Yasuyuki; Ikegami, Sohei; Tanaka, Yoshio; Tokuyasu, Takashi; Sugitsue, Noritake
no journal, ,
no abstracts in English
Takahashi, Nobuo; Morimoto, Yasuyuki; Ikegami, Sohei; Tanaka, Yoshio; Tokuyasu, Takashi; Sugitsue, Noritake
no journal, ,
no abstracts in English
Morimoto, Yasuyuki; Ikegami, Sohei; Tanaka, Yoshio; Tokuyasu, Takashi; Takahashi, Nobuo; Sugitsue, Noritake
no journal, ,
no abstracts in English
Tanaka, Yoshio; Morimoto, Yasuyuki; Ikegami, Sohei; Tokuyasu, Takashi; Takahashi, Nobuo; Sugitsue, Noritake
no journal, ,
no abstracts in English
-ray spectra in living environment around Fukushima Daiichi Nuclear Power PlantTanimura, Yoshihiko; Tomita, Jumpei; Yoshitomi, Hiroshi; Yoshizawa, Michio; Hakozaki, Ryozo*; Takahashi, Sohei*
no journal, ,
A easy-to-use -ray spectrometry technique have been developed using a hand-held NaI(Tl) spectrometer and the MAXED unfolding code. The -ray spectra in the living environment were measured inside and outside the house at the Minami-Soma city in the Fukushima prefecture. It was found that the dose contribution of the low energy photons is large inside the house compared with those measured outside the house.
Tokuyasu, Takashi; Tanaka, Yoshio; Morimoto, Yasuyuki; Ikegami, Sohei; Takahashi, Nobuo; Sugitsue, Noritake
no journal, ,
no abstracts in English
