Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Tanaka, Kosuke; Sato, Isamu*; Onishi, Takashi; Ishikawa, Takashi; Hirosawa, Takashi; Katsuyama, Kozo; Seino, Hiroshi; Ohno, Shuji; Hamada, Hirotsugu; Tokoro, Daishiro*; et al.
Journal of Nuclear Materials, 536, p.152119_1 - 152119_8, 2020/08
Times Cited Count：0 Percentile：0.01(Materials Science, Multidisciplinary)In order to obtain the release rate coefficients from fuels for fast reactors (FRs), heating tests and the subsequent analyses of the fission products (FPs) and actinides that are released were carried out using samples of uranium-plutonium mixed oxide (MOX) fuel pellets irradiated at the experimental fast reactor Joyo. Three heating tests targeting temperatures of 2773, 2973 and 3173 K were conducted using an FP release behavior test apparatus equipped with a high-frequency induction furnace and solid FP sampling systems consisting of a thermal gradient tube (TGT) and filters. Irradiated fuel pellets were placed into a tungsten crucible, then loaded into the induction furnace. The temperature was raised continuously at a heating rate of 10 K/s to the targeted temperature and maintained for 500 s in a flowing argon gas atmosphere. The FPs and actinides released from the MOX fuels and deposited in the TGT and filters were quantified by gamma-ray spectrometry and inductively coupled plasma mass spectrometry (ICP-MS) analysis. Based on the analysis, the release rates of radionuclides from MOX fuels for FR were obtained and compared with literature data for light water reactor (LWR) fuels. The release rate coefficients of FPs obtained in this study were found to be similar to or lower than the literature values for LWR fuels. It was also found that the release rate coefficient data for actinides were within the range of variation of literature values for LWR fuels.
Onishi, Takashi; Sekioka, Ken*; Suto, Mitsuo*; Tanaka, Kosuke; Koyama, Shinichi; Inaba, Yusuke*; Takahashi, Hideharu*; Harigai, Miki*; Takeshita, Kenji*
Energy Procedia, 131, p.151 - 156, 2017/12
Times Cited Count：8 Percentile：98.02no abstracts in English
Usuki, Toshiyuki; Sato, Isamu; Suto, Mitsuo; Maeda, Koji; Osaka, Masahiko; Koyama, Shinichi; Tokoro, Daishiro*; Sekioka, Ken*; Ishigamori, Toshio*
JAEA-Testing 2014-001, 29 Pages, 2014/05
JAEA-Testing-2014-001.pdf:5.33MB
The penetration tests with solution containing radioactive nuclides were experimented to understand basic data for floor and wall materials of Fukushima Daiichi reactor buildings. The solution prepared from irradiated fuels was used as solution containing radioactive nuclides. The solution was applied to surface of epoxy paint, dried concrete and mortar used as specimens. Dose-rate profiles of direction of depth were given by radiation measurement and grinding of the specimens. The penetrations of radioactive nuclides for epoxy paint specimens were not clearly observed and the penetration depths would be within 0.4 mm. The penetrations of radioactive nuclides for dried concrete specimens proceeded. The penetration rates were substantially decreased when 16 days have elapsed from start. The dose rates of penetrated dried concrete specimens were reduced to background by grinding-2.0 mm. 
-ray spectrometry measurement showed that penetration behavior of near surface concrete are different among nuclides and the penetration behavior of radioactive nuclides into dried concrete and mortar materials through solution is similar to migration behavior of ions into those water-saturated materials.
Tanaka, Kosuke; Suto, Mitsuo; Onishi, Takashi; Akutsu, Yoko; Yoshitake, Tsunemitsu; Yamashita, Shinichiro; Sekioka, Ken*; Ishigamori, Toshio*; Obayashi, Hiroshi; Koyama, Shinichi
JAEA-Research 2013-036, 31 Pages, 2013/12
JAEA-Research-2013-036.pdf:3.31MB
In the accident of Fukushima Daiichi NPPs, the water ingress was performed in order to decrease the reactor temperature. At that time, sea water was temporarily used as a coolant and the water contacted with nuclear fuel directly. It can be supposed that fission products (FP) were easily migrated from the fuel to sea water in this situation and that affect the water quality. The knowledge of leaching behavior, therefore, is necessary for evaluating the integrity of reactor component materials such as steels for pressure containment vessel and for reactor vessel. In order to obtain the fundamental knowledge for leaching behavior of FP in the hot sea water, the leaching tests of irradiated fuel were performed and the leachates were subjected to chemical analysis. It is found that he leaching rate of each nuclides obtained in this study were similar to that of the leaching results simulating the underground water.
Takeda, Seiji; Sekioka, Yasushi; Yotsuji, Kenji; Kimura, Hideo; Inagaki, Yaohiro*
no journal, ,
no abstracts in English
Sudo, Mitsuo; Obayashi, Hiroshi; Koyama, Shinichi; Maeda, Shigetaka; Tanaka, Kenya; Sekioka, Ken*
no journal, ,
I carried out the burn-up measurement (Nd monitor method) by the chemical analysis to evaluate a short-term irradiation condition of the "Monju" specifications fuel which contained Am irradiated in "Joyo".
Onishi, Takashi; Sudo, Mitsuo; Koyama, Shinichi; Tanaka, Kenya; Sekioka, Ken*; Shiba, Tomooki*; Sagara, Hiroshi*; Saito, Masaki*
no journal, ,
In order to develop the high proliferation resistance fuel for fast breeder reactor, plutonium production/incineration behavior of americium samples irradiated in fast reactor "JOYO" was evaluated.
Onishi, Takashi; Sudo, Mitsuo; Koyama, Shinichi; Sekioka, Ken*; Shiba, Tomooki*; Sagara, Hiroshi*; Saito, Masaki*
no journal, ,
In order to develop blanket fuel with high proliferation resistance in fast breeder reactor, production and incineration behavior of Pu in U samples irradiated in fast experimental reactor JOYO were evaluated.
Suto, Mitsuo; Obayashi, Hiroshi; Koyama, Shinichi; Sekioka, Ken*; Takeshita, Kenji*; Inaba, Yusuke*; Ogata, Takeshi*; Oaki, Hiroshi*
no journal, ,
no abstracts in English
Onishi, Takashi; Akutsu, Yoko; Obayashi, Hiroshi; Koyama, Shinichi; Sekioka, Ken*; Ishigamori, Toshio*; Mimura, Hitoshi*
no journal, ,
As part of a development of nuclides separation process by using highly-functional xerogels, xerogels including insoluble ferrocyanide compounds were prepared for separation of Pt group metals. Adsorption and elution behaviors of Pt group metals were investigated in simulated high level radioactive liquid waste. Recovery of palladium was also conducted by a thermal decomposition and digestion method.
Usuki, Toshiyuki; Sato, Isamu; Kanayama, Fumihiko; Suto, Mitsuo; Maeda, Koji; Koyama, Shinichi; Kawatsuma, Shinji; Fukushima, Mineo; Tokoro, Daishiro*; Sekioka, Ken*; et al.
no journal, ,
no abstracts in English
Onishi, Takashi; Akutsu, Yoko; Obayashi, Hiroshi; Koyama, Shinichi; Ishigamori, Toshio*; Sekioka, Ken*; Mimura, Hitoshi*; Kawamura, Takuya*; Sugai, Hiroshi*
no journal, ,
As part of a development of nuclides separation process by using highly-functional xerogels, xerogels including insoluble ferrocyanide compounds were prepared for separation of Pt group metals. Adsorption and elution behaviors of Pt group metals were investigated in simulated high level radioactive liquid waste.
Suto, Mitsuo; Obayashi, Hiroshi; Koyama, Shinichi; Sekioka, Ken*; Takeshita, Kenji*; Inaba, Yusuke*; Ogata, Takeshi*; Oaki, Hiroshi*
no journal, ,
no abstracts in English
Usuki, Toshiyuki; Sato, Isamu; Kanayama, Fumihiko; Suto, Mitsuo; Maeda, Koji; Koyama, Shinichi; Kawatsuma, Shinji; Fukushima, Mineo; Tokoro, Daishiro*; Sekioka, Ken*; et al.
no journal, ,
no abstracts in English
Tanaka, Kosuke; Suto, Mitsuo; Onishi, Takashi; Akutsu, Yoko; Obayashi, Hiroshi; Koyama, Shinichi; Yoshitake, Tsunemitsu; Yamashita, Shinichiro; Sekioka, Ken*; Ishigamori, Toshio*
no journal, ,
Chemical analysis of artificial seawater after immersion tests of irradiated fuel was carried out.
Sato, Isamu; Onishi, Takashi; Hirosawa, Takashi; Tanaka, Kosuke; Osaka, Masahiko; Koyama, Shinichi; Tokoro, Daishiro*; Ishigamori, Toshio*; Seki, Takayuki*; Shinada, Masanori*; et al.
no journal, ,
As a material simulating FP, CsI was heated and evaporated to be decomposited on the surface of a tube having a temperature gradient. Gaseous B
O
made by heating it at higher temperature was react with CsI decomposited on the surface, and then the boron effects for decomposition and migration behavior of Cs and I were observed. Consequently, it was indicated that boron vapor could strip decomposited CsI to make it gaseous species again and then the guseous CsI could move to the colder position.
Tanaka, Kosuke; Sato, Isamu; Hirosawa, Takashi; Onishi, Takashi; Suto, Mitsuo; Miwa, Shuhei; Osaka, Masahiko; Koyama, Shinichi; Seki, Takayuki*; Shinada, Masanori*; et al.
no journal, ,
In order to evaluate chemical forms of deposited fission products, ray spectrometry, macroscopic observation, XRD, ICP-MS analysis were performed in the specimens of sampling parts after a heating test of a fuel which was irradiated at FUGEN.
Ishikawa, Takashi; Tanaka, Kosuke; Sato, Isamu*; Onishi, Takashi; Hirosawa, Takashi; Seino, Hiroshi; Ohno, Shuji; Hamada, Hirotsugu; Tokoro, Daishiro*; Sekioka, Ken*; et al.
no journal, ,
no abstracts in English
Onishi, Takashi; Tanaka, Kosuke; Sato, Isamu*; Ishikawa, Takashi; Hirosawa, Takashi; Katsuyama, Kozo; Seino, Hiroshi; Ohno, Shuji; Hamada, Hirotsugu; Tokoro, Daishiro*; et al.
no journal, ,
no abstracts in English
Tanaka, Kosuke; Sato, Isamu*; Onishi, Takashi; Ishikawa, Takashi; Hirosawa, Takashi; Katsuyama, Kozo; Seino, Hiroshi; Ohno, Shuji; Hamada, Hirotsugu; Tokoro, Daishiro*; et al.
no journal, ,
Fractional release rate was evaluated based on the results of chemical analysis of sampling parts on which released nuclides were deposited during the over-heating test of irradiated fuels in a fast reactor.
