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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.
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.
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.
Onishi, Takashi; Koyama, Shinichi; Ishigamori, Toshio*; Mimura, Hitoshi*; Kawamura, Takuya*; Masud, R. S.*; Sugai, Hiroshi*
no journal, ,
no abstracts in English
Iwasaki, Maho; Tanaka, Kosuke; Sato, Isamu; Miwa, Shuhei; Osaka, Masahiko; Amaya, Masaki; Koyama, Shinichi; Seki, Takayuki*; Tokoro, Daishiro*; Ishigamori, Toshio*
no journal, ,
no abstracts in English
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.
Hirosawa, Takashi; Sato, Isamu; Tanaka, Kosuke; Osaka, Masahiko; Koyama, Shinichi; Tokoro, Daishiro*; Ishigamori, Toshio*; Seki, Takayuki*
no journal, ,
In order to demonstrate severe accident condition on BWR, FP gas release test device was alternated to be used under oxidizing atmosphere. As a result, it is confirmed that the oxidation reaction of tungsten part was inhibited under high temperature.