Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Nagai, Yuya; Shuji, Yoshiyuki; Kawasaki, Takeshi; Aita, Takahiro; Kimura, Yasuhisa; Nemoto, Yasunori*; Onuma, Takeshi*; Tomiyama, Noboru*; Hirano, Koji*; Usui, Yasuhiro*; et al.
JAEA-Technology 2022-039, 117 Pages, 2023/06
Japan Atomic Energy Agency (JAEA) manages wide range of nuclear facilities. Many of these facilities are required to be performed adjustment with the aging and complement with the new regulatory standards and the earthquake resistant, since the Great East Japan Earthquake and the Fukushima Daiichi Nuclear Power Station accident. It is therefore desirable to promote decommissioning of facilities that have reached the end of their productive life in order to reduce risk and maintenance costs. However, the progress of facility decommissioning require large amount of money and radioactive waste storage space. In order to address these issues, JAEA has formulated a "The Medium/Long-Term Management Plan of JAEA Facilities" with three pillars: (1) consolidation and prioritization of facilities, (2) assurance of facility safety, and (3) back-end countermeasures. In this plan, Plutonium Fuel Fabrication Facility has been selected as primary decommissioned facility, and dismantling of equipment in the facilities have been underway. In this report, size reduction activities of the glove box W-9 and a part of tunnel F-1, which was connected to W-9, are presented, and the obtained findings are highlighted. The glovebox W-9 had oxidation & reduction furnace, and pellet crushing machine as equipment interior. The duration of activity took six years from February 2014 to February 2020, including suspended period of 4 years due to the enhanced authorization approval process.
Asami, Makoto*; Takahatake, Yoko; Myodo, Masato; Tobita, Takeshi; Kobayashi, Kiwami; Hayakawa, Misa; Usui, Yuka; Watahiki, Hiromi; Shibata, Atsuhiro; Nomura, Kazunori; et al.
JAEA-Data/Code 2017-001, 78 Pages, 2017/03
At Fukushima Daiichi Nuclear Power Station owned by Tokyo Electric Power Company Holdings, Incorporated (TEPCO), contaminated water (accumulated, treated) secondary waste from water treatment, rubble and soil were collected and analyzed. The data already opened to public was collected as this report. The analytical data reported by TEPCO, Japan Atomic Energy Agency and International Research Institute for Nuclear Decommissioning until the end of March, 2016, was collected. Information on the samples and values of radioactive nuclide concentration and others were tabulated, besides figures, which show change in radioactive nuclide concentration for major nuclides, are contained. And, English translation and the collected data are provided as electric data.
Son, N. T.*; Hemmingsson, C. G.*; Paskova, T.*; Evans, K. R.*; Usui, Akira*; Morishita, Norio; Oshima, Takeshi; Isoya, Junichi*; Monemar, B.*; Janzn, E.*
Physical Review B, 80(15), p.153202_1 - 153202_4, 2009/10
Times Cited Count:40 Percentile:79.23(Materials Science, Multidisciplinary)GaN samples were irradiated with electrons of 2 MeV at 110
/cm
, and electron spin resonance (ESR) was measured at 77 K. As a result, four defect signals which are labeled D1 to D4 were observed. The D2 signal was identified to be negatively charged gallium vacancy - oxygen pair from the details studies of
N hf structure.
Kurosawa, Makoto; Ouchi, Shoichi*; Abe, Jiro; Okane, Shogo; Usui, Takeshi
JAERI-Tech 2002-036, 24 Pages, 2002/03
Method for measurement of plutonium in -waste using passive
ray has been adopted at Plutonium Fuel Research Facility. Recently, research of neptunium has been started. It is necessary to evaluate the passive
ray method for measurement of plutonium in
-waste including plutonium and neptunium together. This report describes the results of comparing the two methods, deduction method and division method. The error of deduction method is about 10 to 15% when the quantity of plutonium is larger than 100 mg in the waste. But the error reaches more than 50% when the quantity of plutonium is less than 10 mg and the ratio of plutonium and neptunium is less than one. On the other hand, the error of division method is about a few to 15% when the quantity of plutonium is larger than 100 mg in the waste. The error is about 30 to 50% when the quantity of plutonium is less than 10 mg, but the error is not affected by the ratio of plutonium and neptunium. By reason of this results, the division method is adopted for measurement of plutonium in
-waste including neptunium.
Ouchi, Shoichi*; Kurosawa, Makoto; Abe, Jiro; Okane, Shogo; Usui, Takeshi
JAERI-Tech 2002-026, 35 Pages, 2002/03
Both gloveboxes No.801-W for measuring samples of uranium or plutonium and No.802-W for analyzing the quantity of uranium or plutonium are established at twenty five years ago in the analyzing room No.108 of Plutonium Fuel Research Facility. It was planned to scrap the gloveboxes and to establish new gloveboxes. This report describes the technical view of the scrapping works.
Ito, Takao; Akino, Noboru; Ebisawa, Noboru; Grisham, L. R.*; Honda, Atsushi; Hu, L.*; Kawai, Mikito; Kazawa, Minoru; Kuriyama, Masaaki; Kusaka, Makoto*; et al.
Fusion Engineering and Design, 51-52, p.1039 - 1047, 2000/11
Times Cited Count:15 Percentile:68.02(Nuclear Science & Technology)no abstracts in English
Tamada, Masao; Koshikawa, Hiroshi; Suwa, Takeshi; Yoshioka, Terufumi*; Usui, Hiroaki*; Sato, H.*
Polymer, 41(15), p.5661 - 5667, 2000/07
Times Cited Count:17 Percentile:51.74(Polymer Science)no abstracts in English
Tamada, Masao; Koshikawa, Hiroshi; Hosoi, Fumio; Suwa, Takeshi; Usui, H.*; ; Sato, H.*
Polymer, 40(1), p.3061 - 3067, 1999/00
no abstracts in English
Tsukada, Takashi; Shiba, Kiyoyuki; Nakajima, Hajime; Usui, Takeshi; Omi, Masao; Goto, Ichiro; ; Nakagawa, Tetsuya; Kawamata, Kazuo; ; et al.
JAERI-M 92-165, 41 Pages, 1992/11
no abstracts in English
Noda, Kenji; Sugimoto, Masayoshi; ; Matsuo, Hideto; Watanabe, Katsutoshi; Kikuchi, Teruo; Usui, Takeshi; Oyama, Yukio; Ono, Hideo; Kondo, Tatsuo
Journal of Nuclear Materials, 191-194, p.1367 - 1371, 1992/00
Times Cited Count:9 Percentile:64.83(Materials Science, Multidisciplinary)no abstracts in English