Advanced analysis technology for new material and product development

Sasaki, Hirokazu*; Nishikubo, Hideo*; Nishida, Shinsuke*; Yamazaki, Satoshi*; Nakasaki, Ryusuke*; Isomatsu, Takemi*; Minato, Ryuichiro*; Kinugawa, Kohei*; Imamura, Akihiro*; Otomo, Shinya*; et al.

Furukawa Denko Jiho, (138), p.2 - 10, 2019/02

https://www.furukawa.co.jp/rd/review/fj138/fj138_02.pdf

no abstracts in English

Activities of the interactive public meetings on radiation and its health effect after the TEPCO Fukushima Daiichi Nuclear Power Station accident in the case of Nuclear Fuel Cycle Engineering Laboratories

Sugiyama, Kenji; Ayame, Junko; Takashita, Hirofumi; Yamamoto, Ryuichi

JAEA-Review 2015-013, 75 Pages, 2016/02

JAEA-Review-2015-013.pdf:10.51MB

JAEA has held public meetings on radiation and its health effects mainly for parents of students in kindergartens, elementary schools, and junior high schools in Fukushima prefecture after the Fukushima nuclear accident. These meetings are held based on our experience of practicing risk communication activities for a decade in JAEA with local residents. Questionnaires were collected after the meetings. By analyzing questionnaires, we confirmed that interactive communication is effective in increasing participants' understanding and in decreasing their anxiety. Risk communication study office supported the staff members of the meetings providing information such as participants' questions in the past meetings. To provide information, we made a homepage and held the orientation for the staff members Questionnaires of the staff members were also collected and analyzed after the public meetings.

Questionnaire analysis in the interactive public meetings on radiation and its health effect after the Fukushima nuclear accident

Sugiyama, Kenji; Takashita, Hirofumi; Yamamoto, Ryuichi; Itabashi, Kiyoshi

JAEA-Review 2014-018, 110 Pages, 2014/07

JAEA-Review-2014-018.pdf:9.25MB

JAEA has held public meetings on radiation and its health effects mainly for parents of students in kindergartens, elementary schools, and junior high schools in Fukushima Prefecture after the Fukushima nuclear accident. These meetings are held based on our experience of practicing risk communication activities for a decade in JAEA with local residents. Questionnaires were collected after the meetings. By analyzing questionnaires, we confirmed that interactive communication is effective in increasing participants' understanding and in decreasing their anxiety. Most of the participants answered that they understood the contents and that it eased their mind.

Development of safeguards and maintenance technology in Tokai Reprocessing Plant

Yamamura, Osamu; Yamamoto, Ryuichi; Nomura, Shigeo; Fujii, Yasuhiko*

Progress in Nuclear Energy, 50(2-6), p.666 - 673, 2008/03

https://doi.org/10.1016/j.pnucene.2007.11.054

The application of safeguards to the Tokai Reprocessing Plant(TRP), the world's first reprocessing plant with a sole objective of commercial use, was made on try and error basis because it was the first experience for both the plant and the inspection sides. Through thirty years' faithful cooperation to the IAEA-initiated safeguards program, TRP contributed also to the developments of the international credibility upon the concept of safeguards system of Reprocessing plant in non-nuclear weapon countries. TRP also has been processing over 1,123 ton of spent fuels from the beginning of its active operation in Sept.'77. For 30 years operation of TRP, many technological problems have been overcome to obtain the stable and reliable operation. The process for establishments of maintenance technology in TRP was evaluated through the analysis of significant plant equipment failures reported to the Government and so on. Discussion in this paper is also emphasized that the safeguards system and the maintenance technologies developed by TRP have been applied to the first Rokkasho commercial reprocessing plant (RRP). Furthermore, this operation knowledge base can contribute to the design and construction of the next generation reprocessing plant.

Historical role of the Tokai reprocessing plant in the establishment of safeguards technologies

Yamamura, Osamu; Yamamoto, Ryuichi; Nomura, Shigeo

Journal of Nuclear Materials Management, 36(3), p.36 - 45, 2008/00

This paper describes the role of Tokai Reprocessing Plant (TRP) for the safeguards (SG) technology development by Japan and IAEA and its application to the first large commercial plant in Japan. Through several negotiations between Japan and USA, TRP accepted the full scope application of IAEA's SG, the development of U-Pu mixed conversion process, and the experimental work of IAEA for development of SG activities. Results under the TASTEX, which was research and development program by an agreement made during Japan and USA negotiation on reprocessing, were reflected to the INFCE, which was organized by the change in US atomic energy policy. Most of the current SG technologies being applied by IAEA were developed at this time. Both effectiveness and reliability of such technologies have been validated extensively through the 30 years operation of TRP.

Overview of national centralized tokamak program; Mission, design and strategy to contribute ITER and DEMO

Ninomiya, Hiromasa; Akiba, Masato; Fujii, Tsuneyuki; Fujita, Takaaki; Fujiwara, Masami*; Hamamatsu, Kiyotaka; Hayashi, Nobuhiko; Hosogane, Nobuyuki; Ikeda, Yoshitaka; Inoue, Nobuyuki; et al.

Journal of the Korean Physical Society, 49, p.S428 - S432, 2006/12

To contribute DEMO and ITER, the design to modify the present JT-60U into superconducting coil machine, named National Centralized Tokamak (NCT), is being progressed under nationwide collaborations in Japan. Mission, design and strategy of this NCT program is summarized.

Application of supercritical fluid extraction to metal separation in the field of nuclear technology

Meguro, Yoshihiro; Tomioka, Osamu; Takahashi, Kuniaki; Wada, Ryutaro*; Yamamoto, Seiichi*; Fukuzato, Ryuichi*

Proceedings of 8th International Symposium on Supercritical Fluids (ISSF 2006) (CD-ROM), 6 Pages, 2006/11

A large-scale apparatus having a reaction vessel of ca. 4000 cm was developed for supercritical CO leaching. An ultrasonic wave oscillator, stirring device, and piston compressor were equipped to the apparatus to enhance mass transfer rate of substances in supercritical CO. A sea sand sample, an incinerated ash sample, and a porous alumina brick sample, in which uranium oxide was adsorbed, were prepared as simulated samples of radioactive wastes and uranium was tried to remove from these samples to supercritical CO including nitric acid - tri-n-butyl phosphate complex as a reactant using the apparatus. By several times of the uranium separation, more than 99% of uranium was removed from the sea sand sample and the ash sample. When the mass transfer enhanced system was operated, it was confirmed that separation efficiency of uranium was improved and then 99% of uranium could be removed form the ash sample.

Computer Simulation of Fluid Flow in a Single Fracture with "In-Plane Heterogeneity" (II)

Hosoda, Atsushi*; Sato, Seiji*; Yamamoto, Ryuichi*; Yamamoto, Asao*; Yatake, Yoichi*

JNC TJ8400 2005-007, 145 Pages, 2005/01

JNC-TJ8400-2005-007.pdf:172.71MB

We have conducted the flow and transport simulations using the 3D fracture models with large contact area of fracture faces varying the standard deviation of apertures, and studied the results. Then we have simulated the hydraulic tests for the 10 cm - square natural granite rock samples with a single fracture and compared the results with the measured transmissivity. Finally, we have analyzed the relationship of microscopic and macroscopic fluid property.

Progress in physics and technology developments for the modification of JT-60

Tamai, Hiroshi; Matsukawa, Makoto; Kurita, Genichi; Hayashi, Nobuhiko; Urata, Kazuhiro*; Miura, Yushi; Kizu, Kaname; Tsuchiya, Katsuhiko; Morioka, Atsuhiko; Kudo, Yusuke; et al.

Plasma Science and Technology, 6(1), p.2141 - 2150, 2004/02

https://doi.org/10.1088/1009-0630/6/1/006

The dominant issue for the the modification program of JT-60 (JT-60SC) is to demonstrate the steady state reactor relevant plasma operation. Physics design on plasma parameters, operation scenarios, and the plasma control method are investigated for the achievement of high-. Engineering design and the R&D on the superconducting magnet coils, radiation shield, and vacuum vessel are performed. Recent progress in such physics and technology developments is presented.

Variations of gravity anomaly roughness in Chugoku district, Japan: Relationship with distributions of topographic lineaments

Kudo, Takeshi; Yamamoto, Akihiko*; Nohara, Tsuyoshi; Kinoshita, Hirohisa; Shichi, Ryuichi*

Earth Planets and Space, 56(5), p.e5 - e8, 2004/00

https://doi.org/10.1186/BF03352505

We investigate whether distributions of topographic lineaments in Chugoku district, Japan, may be related to variations of standard deviation (SD) of gravity anomalies. Tectonic movement may disturb lateral continuities of crustal structures at weak zones. These lateral discontinuities of the density structure cause undulations of gravity anomaly fields whose complexities can be an indicator of the past crustal instability. On the other hand, topographic lineaments are formed along weak crustal zones. We would expect therefore that the gravity anomaly complexities have some relations to distributions of surface lineaments. As an index of gravity anomaly complexities in terms of which we interpret spatial distribution of topographic lineaments, we employ Bouguer anomaly SD inside a circular region with adequate radius. The results show that locations of the lineaments, which could be diagnostic of heterogeneity of the previously damaged crust, tend to coincide with those of high SD area