Nakayama, Masashi; Saiga, Atsushi; Kimura, Shun; Mochizuki, Akihito; Aoyagi, Kazuhei; Ono, Hirokazu; Miyakawa, Kazuya; Takeda, Masaki; Hayano, Akira; Matsuoka, Toshiyuki; et al.
JAEA-Research 2019-013, 276 Pages, 2020/03
The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies for geological disposal of High-level Radioactive Waste through investigations of the deep geological environment within the host sedimentary rock at Horonobe Town in Hokkaido, north Japan. The investigations will be conducted in three phases, namely "Phase 1: Surface based investigations", "Phase 2: Construction phase" (investigations during construction of the underground facilities) and "Phase 3: Operation phase" (research in the underground facilities). According to the research plan described in the 3rd Mid- and Long- term Plan of JAEA, "Near-field performance study", "Demonstration of repository design option", and "Verification of crustal-movement buffering capacity of sedimentary rocks" are important issues of the Horonobe URL Project, and schedule of future research and backfill plans of the project will be decided by the end of 2019 Fiscal Year. The present report summarizes the research and development activities of these 3 important issues carried out during 3rd Medium to Long-term Research Phase.
Sato, Yoshiyuki; Aono, Ryuji; Haraga, Tomoko; Ishimori, Kenichiro; Kameo, Yutaka
JAEA-Testing 2019-003, 20 Pages, 2019/12
In the Radioactive Waste Management Technology Section, the radioactive liquid waste generated in the test using natural uranium in the past has been stored based on the contents of permission. Although we decided to perform solidification treatment in order to reduce the risk in storage, no rational treatment method has been established so far. Therefore, we examined adsorption treatment of natural uranium using uranium adsorbent (Tannix), and finally stabilized treatment by cement solidification. The treatment methods and findings obtained for a series of operations in waste liquid treatment are summarized in this report for reference when treating similar liquid waste.
Haraga, Tomoko; Ouchi, Kazuki; Sato, Yoshiyuki; Hoshino, Hitoshi*; Tanana, Rei*; Fujihara, Takashi*; Kurokawa, Hideki*; Shibukawa, Masami*; Ishimori, Kenichiro; Kameo, Yutaka; et al.
Analytica Chimica Acta, 1032, p.188 - 196, 2018/11
The development of safe, rapid and highly sensitive analytical methods for radioactive samples, especially actinide (An) ions, represents an important challenge. Here we propose a methodology for selecting appropriate emissive probes for An ions with very low consumption and emission of radioactivity by capillary electrophoresis-laser-induced fluorescence detection (CE-LIF), using a small chemical library of probes with eight different chelating moieties. It was found that the emissive probe, which possesses the tetradentate chelating moiety, was suitable for detecting uranyl ions. The detection limit for the uranyl-probe complex using CE-LIF combined with dynamic ternary complexation and on-capillary concentration techniques was determined to be 0.7 ppt. This method was successfully applied to real radioactive liquid samples collected from nuclear facilities.
Xu, Z. Y.*; Heylen, H.*; Asahi, Koichiro*; Boulay, F.*; Daugas, J. M.*; de Groote, R. P.*; Gins, W.*; Kamalou, O.*; Koszors, .*; Lykiardopoupou, M.*; et al.
Physics Letters B, 782, p.619 - 626, 2018/07
no abstracts in English
Aono, Ryuji; Sato, Yoshiyuki; Shimada, Asako; Tanaka, Kiwamu; Ueno, Takashi; Ishimori, Kenichiro; Kameo, Yutaka
JAEA-Technology 2017-025, 32 Pages, 2017/11
We have developed analytical methods for Zr, Mo, Pd and Sn, which are considered important in terms of the safety assessment of radioactive waste disposal. The methods are specialized for the wastes left after Fukushima accident. As the main analytical sample, we assumed accumulated water / treated water collected at Fukushima Daiichi Nuclear Power Station. As for Zr, Mo, Pd and Sn contained in this accumulated water / treated water, we have worked on the development of separation and purification method of target nuclide and improvement of recovery, and summarized these results in this report.
Sato, Hisaki*; Takeuchi, Yutaka*; Kakiuchi, Kazuo*; Yamashita, Shinichiro; Nagase, Fumihisa
Proceedings of 2017 Water Reactor Fuel Performance Meeting (WRFPM 2017) (USB Flash Drive), 9 Pages, 2017/09
Since JFY2015, new Japanese national program has been initiated for the purpose of establishing the technical basis to apply ATF for the existing LWRs. SiC is one of ATF candidates material and the comprehensive applicability is being studied in the program, such as fuel rod design, core and plant design, safety evaluation for design basis accident (DBA) and severe accident (SA) as well. As one of the works in the program, the new procedure including fuel rod performance analysis during DBA was developed and the preliminary analysis was conducted. As a result, it was concluded that the typical transient and LOCA behavior between Zircaloy and SiC was not so much different.
Haraga, Tomoko; Sato, Yoshiyuki; Kameo, Yutaka; Saito, Shingo*
Dekomisshoningu Giho, (55), p.22 - 27, 2017/03
no abstracts in English
Sato, Yoshiyuki; Aono, Ryuji; Konda, Miki; Tanaka, Kiwamu; Ueno, Takashi; Ishimori, Kenichiro; Kameo, Yutaka
Proceedings of 54th Annual Meeting of Hot Laboratories and Remote Handling (HOTLAB 2017) (Internet), 13 Pages, 2017/00
no abstracts in English
Sato, Yoshiyuki; Tanaka, Kiwamu; Ueno, Takashi; Ishimori, Kenichiro; Kameo, Yutaka
Hoken Butsuri, 51(4), p.209 - 217, 2016/12
A large amount of contaminated rubbles were generated by the accident at the Fukushima Daiichi Nuclear Power Station (F1NPS). For safe decommissioning of F1NPS, it is important to evaluate the composition and concentration of radionuclides in the rubbles. In this paper, to characterize the rubbles collected at F1NPS in Unit-1, Unit-2 and Unit-3, radiochemical analysis was operated. As a result of radiochemical analysis, -ray-emitting nuclides Co, Cs and Eu, -ray-emitting nuclides H, C, Sr and Tc, and -particle-emitting nuclides Pu, Am and Cm were detected. In contrast, Nb and Eu concentrations were below the detection limit. Measured radioactive concentrations implied that H, C, Co and Sr concentrations depended on Cs concentration respectively. This analysis was characterized the radioactivity concentrations of the rubbles.
Seno, Yasuhiro*; Noguchi, Akira*; Nakayama, Masashi; Sugita, Yutaka; Suto, Shunkichi; Tanai, Kenji; Fujita, Tomoo; Sato, Haruo*
JAEA-Technology 2016-011, 20 Pages, 2016/07
Cementitious materials are expected to be used for the construction of an underground repository for the geological disposal of radioactive wastes. Ordinary Portland Cement(OPC) would conventionally be used in the fields of civil engineering and architecture, however, OPC has the potential to generate a highly alkaline plume (pH12.5), which will likely degrade the performance of other barriers in the repository such as the bentonite buffer and/or host rock. Low alkaline cementitious materials are therefore being developed that will mitigate the generation of a highly alkaline plume. JAEA has developed a High-volume Fly ash Silica fume Cement (HFSC) as a candidate low alkaline cementitious material. The workability of the HFSC shotcrete was confirmed by conducting In-situ full scale construction tests in the Horonobe underground research laboratory. This report summarizes the results of immersion tests to assess the long-term pH behavior of hardened HFSC cement pastes made with mix designs that are expected to be able to be used in the construction of an underground repository in Japan.
Ishiyama, Hironobu*; Jeong, S.-C.*; Watanabe, Yutaka*; Hirayama, Yoshikazu*; Imai, Nobuaki*; Jung, H. S.*; Miyatake, Hiroari*; Oyaizu, Mitsuhiro*; Osa, Akihiko; Otokawa, Yoshinori; et al.
Nuclear Instruments and Methods in Physics Research B, 376, p.379 - 381, 2016/06
Takahashi, Satoru*; Okuda, Yasutake*; Kawabata, Kuniaki; Aonuma, Hitoshi*; Sato, Yutaka*; Iwata, Kenji*
Journal of Signal Processing, 20(2), p.65 - 74, 2016/03
Sato, Katsuya; Ueda, Ryoshiro*; Hase, Yoshihiro; Narumi, Issey*; Ono, Yutaka
JAEA-Review 2015-022, JAEA Takasaki Annual Report 2014, P. 100, 2016/02
Maruyama, Yudai*; Takeda, Kiyoko*; Tomooka, Norihiko*; Sato, Katsuya; Ono, Yutaka; Yokoyama, Tadashi*
JAEA-Review 2015-022, JAEA Takasaki Annual Report 2014, P. 99, 2016/02
Ogino, Chiaki*; Kahar, P.*; Lee, J. M.*; Sato, Katsuya; Ono, Yutaka; Kondo, Akihiko*
JAEA-Review 2015-022, JAEA Takasaki Annual Report 2014, P. 105, 2016/02
Ueda, Ryoshiro*; Sato, Katsuya; Hayashi, Hidenori*; Narumi, Issey*; Ono, Yutaka
JAEA-Review 2015-022, JAEA Takasaki Annual Report 2014, P. 101, 2016/02
Masubuchi, Takashi*; Toguchi, Kazuki*; Hayashi, Hidenori*; Ikenaga, Hiroshi*; Sato, Katsuya; Ono, Yutaka
JAEA-Review 2015-022, JAEA Takasaki Annual Report 2014, P. 106, 2016/02
Sato, Katsuya; Onodera, Takefumi*; Omoso, Kota*; Takeda-Yano, Kiyoko*; Katayama, Takeshi*; Ono, Yutaka; Narumi, Issey*
Genome Announcements (Internet), 4(1), p.e01631-15_1 - e01631-15_2, 2016/01
Sato, Yutaka*; Kokawa, Hiroyuki*; Fujii, Hiromichi*; Yano, Yasuhide; Sekio, Yoshihiro
Metallurgical and Materials Transactions A, 46(12), p.5789 - 5800, 2015/12
Dissimilar friction stir welding (FSW) of an 11% Cr ferritic/martensitic stee (PNC-FMS) to 316-grade austenitic stainless steel was attempted with a view to its potential application to the wrapper tubes of next-generation fast reactors. The mechanical properties and microstructure of the resulting welds were systematically examined, which revealed that FSW produces a defect-free stir zone in which material intermixing is notably absent. That is, both steels are separately distributed along a zigzagging interface in the stir zone when PNC-FMS is placed on the retreating side, with the tool plunging at the butt line. This interface did not act as a fracture site during small-sized tensile testing of the stir zone. Furthermore, the microstructure of the stir zone was refined in both the PNC-FMS and 316 stainless steel sides, resulting in improved mechanical properties over the respective base material regions.
Ono, Yutaka; Hase, Yoshihiro; Sato, Katsuya; Nozawa, Shigeki; Narumi, Issey*
Hoshasen To Sangyo, (138), p.17 - 20, 2015/06
no abstracts in English