Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Takato, Kiyoto
no journal, ,
no abstracts in English
Nishino, Shohei; Ishiyama, Toru; Kawasaki, Ichio
no journal, ,
The purpose of this R&D is the development of removal method for the deposit and the countermeasure of corrosion by solute in the boiler system. In the boiler system, sulfur and iron oxide accumulated on the bottom and stiffened on there. Because the property of this deposit changed to strong acidity, then the generating tube was corroded by it. And the leakage, occurred at generating tube, was found at Dec. 2011. The property of deposit was too hard to remove by pressurized water, and width of each pipe was too narrow to remove by mechanical method, because there was several thousands of generating tube every 30 mm on the bottom. Therefore the effect of lab examination, corrosion test based on materials of the generated tube, was evaluated.
Koyama, Hayato; Aoyama, Yoshio; Sone, Tomoyuki; Haraguchi, Masahiro; Nakazawa, Osamu
no journal, ,
no abstracts in English
,-dialkylamides-nitric acid systems by turbidity measurementTsutsui, Nao; Hakamatsuka, Yasuyuki; Ban, Yasutoshi
no journal, ,
,-dialkylamides (monoamides) have been proposed as alternative extractants to tri-n-butyl phosphate (TBP) in the development of spent nuclear fuel reprocessing. Up to now, however, quantitative estimation of two-phase separation between nitric acid and monoamides has not been carried out. The property of two-phase separation between monoamides (,-di(2-ethylhexyl)-butanamide (DEHBA) and ,-di(2-ethylhexyl)-2,2-dimethylpropanamide (DEHDMPA)) and TBP diluted by dodecane and nitric acid were studied using by a turbidity analyzer. In the case of TBP, two-phase separation proceeded rapidly regardless of the nitric acid concentration. The time require for two-phase separation decreased with increasing the nitric acid concentration in the presence of DEHBA. It took relatively long time for two-phase separation in the DEHDMPA-nitric acid system compared with the other two systems, and the separation time was independent of the nitric acid concentration.
Sasaki, Yu; Aoyama, Yoshio; Sone, Tomoyuki; Haraguchi, Masahiro; Nakazawa, Osamu
no journal, ,
no abstracts in English
Nakayama, Takuya; Kawato, Yoshimi; Meguro, Yoshihiro
no journal, ,
no abstracts in English
Yamamoto, Masahiko; Taguchi, Shigeo; Surugaya, Naoki; Sato, Soichi
no journal, ,
no abstracts in English
Tanno, Takashi; Otsuka, Satoshi; Yano, Yasuhide; Tanaka, Kenya; Oba, Yojiro*; Onuma, Masato*
no journal, ,
The 9Cr-ODS martensitic steel is under development as first candidate material for fast reactor long life fuel cladding, because of its superior high temperature strength, irradiation resistance and productivility. The 11Cr-ODS steels with additional corrosion resistance by Cr enrichment are also under development, and the evaluation of their applicability for cladding material is in progress. Trial manufacturing, high temperature tensile test, creep test and nano/meso structure evaluation of several ODS steels were carried out to modify the chemical composition and manufacturing process of the 11Cr-ODS steel. Uni-axial creep strength of manufactured 11Cr-ODS steels were equal to or higher than that of 9Cr-ODS steel. The residual 
-ferrite fraction in 11Cr-ODS steels was also controlled at the same level as that of the 9Cr-ODS steel. The creep strength had a linear correlation with the dispersion condition, which is defined by the size and number density of dispersed-oxide.
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
Yasuo, Kiyoshi; Morimoto, Kenji; Seto, Nobuhiko; Watahiki, Seiichi
no journal, ,
JP, 2009-105389 
Patent publication (In Japanese)
Cells and vessels as well as buildings have maintained as a negative pressure to keep nuclear materials inside. Differential pressure switches, detecting change of liquid level and pressure at reprocessing plant, have been required airtightness for the nuclear materials containment under negative pressure. Problem of using the conventional airtight switch is, however, that could not meet the acceptable range with deep negative pressure. We have designed and made a prototype airtight switch applying a new type of pressure detection component. The prototype switch has been reliable on the actual usage, which has been evaluated by an operation, a vibration and an endurance test. We are improving its quality for adapting to the reprocessing process.
Ohata, Fumikazu; Takahatake, Yoko; Nakamura, Masahiro; Koma, Yoshikazu; Shibata, Atsuhiro; Nakajima, Yasuo
no journal, ,
no abstracts in English
Nakamura, Shigetoshi; Sakurai, Shinji; Ozaki, Hidetsugu; Sakasai, Akira; Seki, Yohji; Yokoyama, Kenji
no journal, ,
no abstracts in English
-ray detectorOtsuka, Noriaki; Takeuchi, Tomoaki; Shibata, Akira; Nagata, Hiroshi; Tsuchiya, Kunihiko; Miura, Kuniaki*
no journal, ,
no abstracts in English
Ogawa, Tsuyoshi; Takahatake, Yoko; Watanabe, So; Nakamura, Masahiro; Koma, Yoshikazu; Nakajima, Yasuo
no journal, ,
no abstracts in English
Doi, Reisuke
no journal, ,
For the purpose of studying the temperature influence on the standard potential(E
) of the Se(VI/IV) redox system, cyclic voltammetry has been performed. With the specific ion interaction theory (SIT) applied to estimate the activity factor, E of (HSeO
/H
SeO
) redox system was determined at 15, 25, 35, 50
C. E at 25C by this work was in accordance with that of the other Se(VI/IV) redox reaction by our previous work. The variation of E versus temperature gave straight line whose slope lead to 
E/T= 
S/2F=-5.1
0.2mV/C. This study could contribute to the estimate of Se species especially in the oxidizing groundwater where the temperature is other than 25C.
pellets for 
Mo/ 
Tc productionNishikata, Kaori; Kimura, Akihiro; Kato, Yoshiaki; Kurosawa, Makoto; Ishida, Takuya; Tsuchiya, Kunihiko; Kakei, Sadanori*; Yoshinaga, Hideo*; Niizeki, Tomotake*; Hasegawa, Yoshio*
no journal, ,
no abstracts in English
Miyauchi, Atsushi; Nakajima, Masayoshi
no journal, ,
no abstracts in English
Naito, Hiroyuki; Itagaki, Wataru; Ito, Chikara; Imaizumi, Kazuyuki; Nagai, Akinori; Tobita, Koichi
no journal, ,
no abstracts in English
Morita, Keisuke
no journal, ,
no abstracts in English
Hayashi, Takehiro; Sasaki, Shinji; Mashiko, Shinichi*; Yamagata, Ichiro; Ogawa, Ryuichiro; Inoue, Masaki; Yamashita, Shinichiro
no journal, ,
In the Great East Japan Earthquake, the Fukushima Dai-ichi Nuclear Power Plants (1F) were in station blackout and dropped their cooling power. To cool the plants, seawater was poured into 1F buildings included SFP. In this study, the immersion tests were carried out with artificial seawater to evaluate the effect on the strength properties of Zircaloy-2 cladding tubes in seawater. The results indicated the growth of corrosion was not observed in microstructures on the surface of Zircaloy-2 tubes, and there were no significant changes in the tensile properties.