Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Kinase, Sakae; Kimura, Masanori; Hato, Shinji*
no journal, ,
no abstracts in English
Kimura, Masanori; Kinase, Sakae; Hato, Shinji*
no journal, ,
no abstracts in English
Hato, Shinji*; Kinase, Sakae; Kimura, Masanori
no journal, ,
no abstracts in English
Fujita, Hiroki; Jain, M.*; Murray, A.*
no journal, ,
Common salt (NaCl) has previously been suggested for use in dose estimation in accident dosimetry. In this study, we investigated the optically stimulated luminescence (OSL) and violet thermoluminescence (VTL) characteristics of "Aji-Shio" (Ajinomoto), a Japanese commercial salt. A comparison of OSL and TL signals allowed identification of common source traps. A single-aliquot regenerative-dose (SAR) OSL protocol was modified and tested. The protocol worked very well for six types of salt, but not for four other types of salt. A minimum detection limit of 15 mGy was estimated using the OSL protocol; this is lower than the value obtained from other forms of OSL retrospective dosimetry and lower than that obtained using electron spin resonance (ESR) dosimetry. It was concluded that the OSL from Japanese commercial salt could be used successfully to derive precise estimates of accident dose.
Nakajima, Junya; Yokosuka, Yoshiyuki; Arakawa, Yuto; Shimizu, Isamu; Umehara, Takashi
no journal, ,
In NUCEF we monitor the radiation level continuously with 81 radiation monitors. Although these monitors are checked periodically, failures have occurred due to various reasons. Then we accumulated all monitor failures which had happened in recent 18 years, and categorized them by reason. This allowed us to find that the number of the failure much differs from monitor to monitor, and that there was a deviation between the reasons of the failure. After that, about degradation of GM tube used as dust monitor, which is by far the most of all reasons, we investigated the relation between the average cps and the interval of exchange. As a result, we couldn't find any causal relationship between the both. On the other hand, to improve the failure situation, we have exchanged expendables periodically, and furthermore, the result of the failure analysis should be fed back for better preventive maintenance.
Usui, Toshihide; Nakayama, Naoto; Iwasa, Atsutoshi; Miura, Yoshiyuki; Ishida, Keiichi; Irokawa, Hiroyuki; Hamazaki, Masaaki; Okawa, Yasuhisa; Iwai, Ryo
no journal, ,
no abstracts in English
Morishita, Yuki; Sagawa, Naoki; Tsubaki, Hirohiko; Izaki, Kenji; Mizuniwa, Harumi
no journal, ,
no abstracts in English
-ray spectra of fallout collected at Tokai-mura during the Fukushima accidentSaegusa, Jun; Akino, Hitoshi; Kikuta, Yasuaki
no journal, ,
Measurements of -ray pulse height distributions (PHD) were performed for a fallout sample collected at Tokai-mura during Fukushima accident in March, 2011. The fallout was collected in a pan of water, then evaporated to dryness on a stainless-steel holder. The sample was measured by a Ge detector three times over a year. In the PHD of the initial measurement, approximately 140 peaks were observed between 50 and 2048 keV energy region. Most of the peaks were either the total absorption peak or the sum peak of Te, I or Cs isotopes. Compared to the PHDs of fallout sampled at the past nuclear accidents, while some nuclides such as 
Ce were not detected, 
Ag etc was prominently observed. Ratio of two different radionuclides, such as 
Zr/Nb, was no resemblance to that of the past data.
Kanai, Katsuta; Kurihara, Osamu*; Takada, Chie; Nakagawa, Takahiro; Morishita, Yuki; Hokama, Tomonori; Takimoto, Misaki; Maruo, Yoshihiro; Momose, Takumaro
no journal, ,
no abstracts in English
Nakagawa, Takahiro; Takada, Chie; Kanai, Katsuta; Murayama, Takashi; Miyauchi, Hideaki; Suzuki, Takehiko; Sato, Yoshitaka; Ezaki, Hiroko; Imahashi, Atsushi; Isozaki, Kohei; et al.
no journal, ,
no abstracts in English
Kono, Takahiko; Nagaoka, Mika; Yokoyama, Hiroya; Fujita, Hiroki; Nakano, Masanao; Watanabe, Hitoshi; Sumiya, Shuichi
no journal, ,
no abstracts in English
and dose rates in the outdoor environment of the Fukushima Dai-ichi Nuclear Power Plant SiteTsujimura, Norio; Yoshida, Tadayoshi
no journal, ,
no abstracts in English
Am-Li neutron calibration fieldYoshida, Tadayoshi; Tsujimura, Norio
no journal, ,
no abstracts in English
Taki, Mitsumasa; Okura, Takehisa; Oishi, Tetsuya
no journal, ,
no abstracts in English
Yoshitake, Takayasu*; Ono, Koji*; Hasegawa, Takayuki*; Katsunuma, Yasushi*; Sato, Kaoru; Takahashi, Fumiaki; Endo, Akira; Ban, Nobuhiko*; Kai, Michiaki*
no journal, ,
Since 2000s, computed tomography (CT) examination has significantly increased at medical treatment in Japan. Therefore, it is very interested in radiation exposure doses derived from CT examinations. We started development of a web-based system, named WAZA-ARI, which can assess radiation doses more accurately now in Japan in 2007. So far a beam-shaping (bow-tie) filter was newly constructed for the X-ray source model of CT device by using PHITS code. In this study, CTDI phantom, which dosimeter was placed in center or periphery, was irradiated with X-ray of CT device. In order to validate WAZA-ARI, measured values were compared with calculated values by PHITS code. The dose differences of center in CTDI phantom between measurement and calculation were within 2-5%.
Yamada, Junya; Seya, Natsumi; Muto, Yasunobu; Shimizu, Takehiko; Takasaki, Koji
no journal, ,
no abstracts in English
Muto, Yasunobu; Yamada, Junya; Seya, Natsumi; Shimizu, Takehiko; Takasaki, Koji; Nakajima, Akemi
no journal, ,
no abstracts in English
-ray calibration field at the FRS of JAEAKowatari, Munehiko; Tanimura, Yoshihiko; Tsutsumi, Masahiro; Kawasaki, Katsuya; Yoshizawa, Michio
no journal, ,
A 6-7 MeV high energy -ray field is to be established as a calibration field for radiation protection instruments at the Facility of Radiation Standards (FRS) of Japan Atomic Energy Agency (JAEA). This calibration field is essential to measure dose rates in accurate due to -rays which are observed around BWRs. The -ray field has been produced through the reaction of 
F(p,
)
O reaction using the accelerator. For establishing the calibration field, there are some difficulties to overcome which are caused by its -ray energy. In the presentation, these difficulties will be presented and discussions concerning the establishment of the high energy -ray calibration field will be made.
Yoshitomi, Hiroshi; Tatebe, Yosuke; Kowatari, Munehiko; Kawai, Keiichi; Miyauchi, Hideaki; Yoshizawa, Michio
no journal, ,
no abstracts in English
Sekita, Tsutomu; Kobayashi, Toshiaki; Hiraga, Hayato; Yasuda, Takayuki; Kikuchi, Masamitsu; Tsunoda, Masahiko
no journal, ,
no abstracts in English