Decommissioning of uranium handling facility for development of nuclear fuel manufacturing equipment

Kageyama, Tomio; Denuma, Akio; Koizumi, Jin*; Odakura, Manabu*; Haginoya, Masahiro*; Isaka, Shinichi*; Kadowaki, Hiroyuki*; Kobayashi, Shingo*; Morimoto, Taisei*; Kato, Yoshiaki*; et al.

JAEA-Technology 2022-033, 130 Pages, 2023/03

JAEA-Technology-2022-033.pdf:9.87MB

Uranium handling facility for development of nuclear fuel manufacturing equipment (Mockup room) was constructed in 1972. The Mockup room has a weak seismic resistance and is deteriorating with age. Also, the original purpose with this facility have been achieved and there are no new development plans using this facility. Therefore, interior equipment installed in this facility had been dismantled and removed since March 2019. After that, the Mockup room was inspected for contamination, and then controlled area in the Mockup room was cancelled on March 29th 2022. A total of 6,549 workers (not including security witnesses) were required for this work. The amount of non-radioactive waste generated by this work was 31,300 kg. The amount of radioactive waste generated by this work was 3,734 kg of combustible waste (103 drums), 4,393 kg of flame resistance waste (61 drums), 37,790 kg of non-combustible waste (124 drums, 19 containers). This report describes about the dismantling and removing the interior equipment in the Mockup room, the amount of waste generated by this work, and procedure for cancellation the controlled area in the facility.

Local structure study of the iron-based systems of BaFeAs and LiFeAs by X-ray PDF and XAFS analyses

Li, S.*; Toyoda, Masayuki*; Kobayashi, Yoshiaki*; Ito, Masayuki*; Ikeuchi, Kazuhiko*; Yoneda, Yasuhiro; Otani, Akira*; Matsumura, Daiju; Asano, Shun*; Mizuki, Junichiro*; et al.

Physica C, 555, p.45 - 53, 2018/12

https://doi.org/10.1016/j.physc.2018.10.003

-dependence of local distortions in BaFeAs and LiFeAs by X-ray PDF and XAFS methods. Although PDF data exhibit anomaly at the structure transition temperature, EXAFS data exhibit no anomaly. Data supporting the local orthorhombicity at 300 K in the tetragonal phase for BaFeAs. Arguments on the origins of the 4-fold symmetry breaking in the ground average structure of the tetragonal phase.

Study on engineering technologies in the Mizunami Underground Research Laboratory (FY 2014); Development of design and construction planning and countermeasure technologies (Contract research)

Kobayashi, Shinji*; Niimi, Katsuyuki*; Tsuji, Masakuni*; Yamada, Toshiko*; Aoyagi, Yoshiaki; Sato, Toshinori; Mikake, Shinichiro; Osawa, Hideaki

JAEA-Technology 2015-039, 170 Pages, 2016/02

JAEA-Technology-2015-039.pdf:37.73MB

The researches on engineering technology in the Mizunami Underground Research Laboratory (MIU) plan consists of (1) development of design and construction planning technologies, (2) development of construction technology, (3) development of countermeasure technology, (4) development of technology for security, and (5) development of technologies regarding restoration or reversal and mitigating of the excavation effect. To develop design and construction planning technologies, and countermeasure technology, the analysis of measured data during earthquake and seismic movement characteristics at deep underground, and the examination of grouting method were carried out. For the characteristics of earthquake ground motion, measurement data obtained by seismometers installed in the Mizunami Underground Laboratory were analyzed, and the comprehensive assessment of the relationship between the measurement data and the geological condition at each depth was performed. As for "Study on grouting method at deep underground ", post grouting was carried out and evaluated based on the Construction plan in FY2013. Furthermore, target of the future R&D was proposed.

Study on engineering technologies in the Mizunami Underground Research Laboratory (FY 2013); Development of design and construction planning and countermeasure technologies (Contract research)

Kobayashi, Shinji*; Niimi, Katsuyuki*; Okihara, Mitsunobu*; Tsuji, Masakuni*; Yamada, Toshiko*; Sato, Toshinori; Mikake, Shinichiro; Horiuchi, Yasuharu*; Aoyagi, Yoshiaki

JAEA-Technology 2014-035, 172 Pages, 2015/01

JAEA-Technology-2014-035.pdf:91.27MB

The researches on engineering technology in the Mizunami Underground Research Laboratory (MIU) plan consists of (1) development of design and construction planning technologies, (2) development of construction technology, (3) development of countermeasure technology, (4) development of technology for security, and (5) development of technologies regarding restoration or reversal and mitigating of the excavation effect. To develop design and construction planning technologies, and countermeasure technology, the analysis of measured data during earthquake and seismic movement characteristics at deep underground, and the examination of grouting method were carried out. The knowledge of the seismic movements at deep underground was obtained by which observation records of seismometers at Mizunami underground research laboratory were analyzed to verify the earthquake-resistant design of the shafts and tunnels. As for" Study on grouting method at deep underground", Existing post-grouting methods for crystalline rock were reviewed, the applicability of pre-grouting technology was evaluated and study on experiment plan in MIU was carried out following the previous year.

The Possible interplanetary transfer of microbes; Assessing the viability of spp. under the ISS environmental conditions for performing exposure experiments of microbes in the Tanpopo mission

Kawaguchi, Yuko*; Yang, Y.*; Kawashiri, Narutoshi*; Shiraishi, Keisuke*; Takasu, Masako*; Narumi, Issey*; Sato, Katsuya; Hashimoto, Hirofumi*; Nakagawa, Kazumichi*; Tanigawa, Yoshiaki*; et al.

Origins of Life and Evolution of Biospheres, 43(4-5), p.411 - 428, 2013/10

https://doi.org/10.1007/s11084-013-9346-1

Structural studies of pyrochlore-related spin-1/2 system AgCuO

Uematsu, Daisuke*; Soda, Minoru*; Kobayashi, Yoshiaki*; Sato, Masatoshi*; Igawa, Naoki; Kakurai, Kazuhisa

Journal of the Physical Society of Japan, 75(12), p.124601_1 - 124601_5, 2006/12

https://doi.org/10.1143/JPSJ.75.124601

The close coupling of the crystal distortion to the magnetic ordering in AgCuO at 70K has been found by X-ray and neutron diffraction analyses and magnetic measurements. The system has a pyrochlore-related structure with corner-sharing tetrahedra of Cu ions, in which the geometrical frustration is inherent. We report how the structural distortion releases the frustration, stabilizing the magnetic ordered state.

Magnetic structure and the hall resistivity of CuZnCrSe

Iikubo, Satoshi*; Yasui, Yukio*; Oda, Keisuke*; Ono, Yohei*; Kobayashi, Yoshiaki*; Sato, Masatoshi*; Kakurai, Kazuhisa

Journal of the Physical Society of Japan, 71(11), p.2792 - 2799, 2002/11

https://doi.org/10.1143/JPSJ.71.2792

no abstracts in English

Replacement of pressure surge tank and vent valves in JMTR

Ishii, Toshimitsu; Ooka, Norikazu; Saito, Junichi; Kobayashi, Shunichi; Takahashi, Kunihiro; Tsukada, Takashi; Iwai, Takashi; Kurosawa, Yoshiaki; Hoshiya, Taiji; Tsuji, Hirokazu

Proceedings of International Symposium on Case Histories on Integrity and Failures in Industry (CHIFI), p.227 - 236, 1999/00

no abstracts in English

None

Fukuda, Kazuhito; Ogata, Yoshiaki; Maki, Akira; ; Kobayashi, Kentaro;

Donen Giho, (96), p.71 - 75, 1995/12

https://jopss.jaea.go.jp/pdfdata/PNC-TN1340-95-004.pdf

None

Core-Plenum interaction experiments; Investigation on onset condition depth penetration flow

Kobayashi, Jun; Ohshima, Hiroyuki; Kamide, Hideki; Ieda, Yoshiaki

PNC TN9410 94-277, 81 Pages, 1994/09

PNC-TN9410-94-277.pdf:2.6MB

In the case that the Direct Reactor Auxiliary Cooling System (DRACS) is adapted as a decay heat removal system of FBR, cold fluid coming from the heat exchangers immersed directly in the hot plenum may penetrate into some subassemblies under a certain natural circulation condition. This phenomenon is important from the viewpoint of the coolability of the core, because it affects the temperature distribution in the subassemblies and the natural circulation head in a primary cooling system. The objective of this study is to obtain the fundamental understanding of the penetration phenomenon with water experiments. The test section is composed of a plenum, a cooled wall and a vertical channe1, which simulate the hot plenum, the heat exchanger and lower power subassembly, respectively. The inlet temperature of water is kept constant during a run of experiments. The velocity and temperature fields in the vertical channel are measured simultaneously with two instruments: Ultrasonic velocity Profile monitor (UVP) for an axial profile of the vertical velocity components and T-type (copper-constantan) thermocouples for the temperature fields. Inlet temperature and flow rate are selected as experimental parameters. Results of the tests are follows: (1)The transient axial profiles of velocity in the vertical channel were compared with those of temperature under the condition that the penetration flow was observed. The trend of temperature profiles agreed well with that of velocity profiles. It was, therefore, considered that the depth of the penetration flow could be estimated with the temperature data as well as the velocity data. (2)The penetraion depth is determined based on buoyancy, inertia, conduction and entrainment effects. With dimensional analysis, Gr/Re and Pr number were derived as relevant parameters for the depth of penetration flow, z: z=f(Gr/Re, Pr). In our experiments, the depth of penetration flow could be correlated with Gr/Re as ...