Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Oyaizu, Makoto; Isobe, Kanetsugu; Hayashi, Takumi
Fusion Science and Technology, 67(3), p.519 - 522, 2015/04
Times Cited Count：2 Percentile：17.57(Nuclear Science & Technology)The effects of tritiated water on the corrosion behavior of chromium were electrochemically studied by anodic polarization measurements with changing tritium concentration and dissolved oxygen concentration as parameters in the electrolyte of 0.01N sulfuric acid solution, self-passivation due to dissolved oxygen could be observed in pure water without tritium. As a result, it was found that the self-passivation was inhibited in tritiated electrolyte as shown in the previous studies for SUS304 stainless steel. It is indicated from the result that the passivation inhibitory effect for SUS304 stainless steel could be induced by dissolution of chromium in passivation film on SUS304 stainless steel.
Hoshino, Tsuyoshi; Ochiai, Kentaro; Edao, Yuki; Kawamura, Yoshinori
Fusion Science and Technology, 67(2), p.386 - 389, 2015/03
Times Cited Count：13 Percentile：73.22(Nuclear Science & Technology)Demonstration power reactors (DEMOs) require advanced tritium breeders that have high stability at high temperatures. Therefore, the pebble fabrication of Li
TiO
with excess Li (Li
TiO
) as an advanced tritium breeder was carried out. In this study, a preliminary examination of the tritium release properties of advanced tritium breeders was performed. DT neutron irradiation experiments were performed at the fusion neutronics source (FNS) facility in JAEA. The LiTiO pebbles exhibited good tritium release properties similar to the LiTiO pebbles. In particular, the released amount of HT gas for easier tritium handling was higher than that of HTO water.
Hayashi, Takumi; Nakamura, Hirofumi; Kawamura, Yoshinori; Iwai, Yasunori; Isobe, Kanetsugu; Yamada, Masayuki; Suzuki, Takumi; Kurata, Rie; Oyaizu, Makoto; Edao, Yuki; et al.
Fusion Science and Technology, 67(2), p.365 - 370, 2015/03
Times Cited Count：1 Percentile：9.74(Nuclear Science & Technology)Edao, Yuki; Kawamura, Yoshinori; Kurata, Rie; Fukada, Satoshi*; Takeishi, Toshiharu*; Hayashi, Takumi; Yamanishi, Toshihiko
Fusion Science and Technology, 67(2), p.320 - 323, 2015/03
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)The present study aims at obtaining fundamental knowledge for tritium transfer behavior and interaction between tritium and paint coated on concrete walls. The amounts of tritium penetration and release in cement paste with epoxy and urethane paint coatings were measured. The tritium penetration amounts were increased with the HTO exposure time. Time to achieve each saturate tritium value was more than 60 days for cement paste coated with epoxy paint and with urethane paint, while cement paste without paint took 2 days to achieve it. Tritium penetration rates were estimated by an analysis of diffusion model. Although their paint coatings were effective for reduction of tritium penetration through the cement paste exposed to HTO for a short period, the amount of tritium trapped in the paints became large for a long time. This work has been performed under the collaboration research between JAEA and Kyushu University.
Kobayashi, Kazuhiro; Torikai, Yuji*; Saito, Makiko; Alimov, V. Kh.*; Miya, Naoyuki; Ikeda, Yoshitaka
Fusion Science and Technology, 67(2), p.428 - 431, 2015/03
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Disassembly of the JT-60U torus was started in 2010 after 18 years deuterium operations. In the disassembly of the JT-60U torus, tritium retention in the vacuum vessel of the JT-60U is one of the most important safety issues for the fusion reactor. It was very important to study the tritium behavior in Inconel 625 from viewpoint of the clearance procedure in the future plan. After the tritium release for about 1 year at 298 K, the residual tritium in the specimen was released by heating up to 1073 K, and then the residual tritium in the specimen was measured by chemical etching method. Most of the chemical form of the released tritium was HTO. The contaminated specimen by tritium was released continuously the diffusible tritium under the ambient condition. In the tritium release experiment, most of tritium in the specimen was released during 1 year.
Fukada, Satoshi*; Katayama, Kazunari*; Takeishi, Toshiharu*; Edao, Yuki; Kawamura, Yoshinori; Hayashi, Takumi; Yamanishi, Toshihiko
Fusion Science and Technology, 67(2), p.99 - 102, 2015/03
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Isobe, Kanetsugu; Hayashi, Takumi
no journal, ,
Effects of TIG welding, which is one of popular welding methods, on hydrogen isotopes permeation in SUS304 stainless steel were investigated. Tube type of SUS304 stainless steels were used as specimens. One end of the tube was sealed up with a same metal and another end was connected with both a vacuum pumping system and a gas supply system. A tube type of specimen was placed on the vacuum chamber equipped with a quadrupole mass spectrometer (QMS). Deuterium gas was supplied for the inner of tube specimen and the pressure of deuterium gas was kept at 0.2 MPa. Deuterium permeated through specimen was released into the vacuum chamber and was continuously measured with QMS at from 423 K to 673 K. The permeation behavior is found to be almost same over at 623 K, however, TIG welding slightly increased permeation flux at 573 and 523 K.
