Annual report for research on geosphere stability for long-term isolation of radioactive waste in fiscal year 2019

Ishimaru, Tsuneari; Ogata, Nobuhisa; Kokubu, Yoko; Shimada, Koji; Hanamuro, Takahiro; Shimada, Akiomi; Niwa, Masakazu; Asamori, Koichi; Watanabe, Takahiro; Sueoka, Shigeru; et al.

JAEA-Research 2020-011, 67 Pages, 2020/10

JAEA-Research-2020-011.pdf:3.87MB

This annual report documents the progress of research and development (R&D) in the 5th fiscal year during the JAEA 3rd Mid- and Long-term Plan (fiscal years 2015-2021) to provide the scientific base for assessing geosphere stability for long-term isolation of the high-level radioactive waste. The planned framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques. The current status of R&D activities with previous scientific and technological progress is summarized.

How different is the core of F from O ?

Tang, T. L.*; Uesaka, Tomohiro*; Kawase, Shoichiro; Beaumel, D.*; Dozono, Masanori*; Fujii, Toshihiko*; Fukuda, Naoki*; Fukunaga, Taku*; Galindo-Uribarri, A.*; Hwang, S. H.*; et al.

Physical Review Letters, 124(21), p.212502_1 - 212502_6, 2020/05

https://doi.org/10.1103/PhysRevLett.124.212502

The structure of a neutron-rich F nucleus is investigated by a quasifree () knockout reaction. The sum of spectroscopic factors of orbital is found to be 1.0 0.3. The result shows that the O core of F nucleus significantly differs from a free O nucleus, and the core consists of 35% O, and 65% excited O. The result shows that the O core of F nucleus significantly differs from a free O nucleus. The result may infer that the addition of the proton considerably changes the neutron structure in F from that in O, which could be a possible mechanism responsible for the oxygen dripline anomaly.

Research plan on geosphere stability for long-term isolation of radioactive waste (Scientific program for fiscal year 2019)

Ishimaru, Tsuneari; Ogata, Nobuhisa; Hanamuro, Takahiro; Shimada, Akiomi; Kokubu, Yoko; Asamori, Koichi; Niwa, Masakazu; Shimada, Koji; Watanabe, Takahiro; Sueoka, Shigeru; et al.

JAEA-Review 2019-010, 46 Pages, 2019/09

JAEA-Review-2019-010.pdf:2.45MB

This report is a plan of research and development (R&D) on geosphere stability for long-term isolation of high-level radioactive waste (HLW) in Japan Atomic Energy Agency, in fiscal year 2019. The objectives and contents in fiscal year 2019 are described in detail based on the outline of 7 years plan (fiscal years 2015-2021). Background of this research is clarified with the necessity and the significance for site investigation and safety assessment, and the past progress in this report. In addition, the plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques.

Research plan on geosphere stability for long-term isolation of radioactive waste (Scientific Program for fiscal year 2018)

Ishimaru, Tsuneari; Ogata, Nobuhisa; Shimada, Akiomi; Asamori, Koichi; Kokubu, Yoko; Niwa, Masakazu; Watanabe, Takahiro; Saiga, Atsushi; Sueoka, Shigeru; Komatsu, Tetsuya; et al.

JAEA-Review 2018-020, 46 Pages, 2019/01

JAEA-Review-2018-020.pdf:1.25MB

This report is a plan of research and development (R&D) on geosphere stability for long-term isolation of high-level radioactive waste (HLW) in Japan Atomic Energy Agency, in fiscal year 2018. The objectives and contents in fiscal year 2018 are described in detail based on the outline of 7 years plan (fiscal years 2015-2021). Background of this research is clarified with the necessity and the significance for site investigation and safety assessment, and the past progress in this report. In addition, the plan framework is structured into the following categories: (1) Development and systematization of investigation techniques, (2) Development of models for long-term estimation and effective assessment, (3) Development of dating techniques.

Development of structures for ITER toroidal field coil in Japan

Iguchi, Masahide; Chida, Yutaka; Takano, Katsutoshi; Kawano, Katsumi; Saito, Toru; Nakajima, Hideo; Koizumi, Norikiyo; Minemura, Toshiyuki*; Ogata, Hiroshige*; Ogawa, Tsuyoshi*; et al.

IEEE Transactions on Applied Superconductivity, 22(3), p.4203305_1 - 4203305_5, 2012/06

https://doi.org/10.1109/TASC.2011.2177795

Japan Atomic Energy Agency (JAEA) has responsibility to procure 19 structures for ITER toroidal field (TF) coils as in-kind components. JAEA plans to use materials specified in the material section of "Codes for Fusion Facilities; Rules on Superconducting Magnet Structure (2008)" issued by the Japan Society of Mechanical Engineers (JSME) in 2008. Large forged products were produced and their mechanical properties at 4K were evaluated. In addition, the following activities have been performed; (1) to optimize the design of each weld type identified in the manufacturing sequence, (2) to qualify typical welding procedure including repair, (3) to establish welding techniques other than narrow gap TIG welding with FMYJJ1, (4) to demonstrate the manufacturing procedures through manufacture of 1-m mockups and full-scale segments of TFC structure. This paper describes the results of material qualification and industrialization activities of manufacturing processes of ITER TFC structure.

Development of a laser-plasma ion source at the advanced photon research center

Daido, Hiroyuki; Yamakawa, Koichi; Yamagiwa, Mitsuru; Arisawa, Takashi; Kato, Yoshiaki; Noda, Akira*; Uesaka, Mitsuru*; Ogata, Atsushi*; Matsukado, Koji*

Proceedings of 4th Symposium on Accelerator and Related Technology for Application, p.111 - 112, 2001/10

no abstracts in English

Fracture analysis in crystalline rock with method of multivariate analysis

Ogata, Nobuhisa; Osawa, Hideaki; Semba, Tsuyoshi; Yanagizawa, Koichi

PNC TN7410 92-001, 48 Pages, 1992/01

PNC-TN7410-92-001.pdf:1.71MB

In order to groundwater flow in rock formation, it is essential to make a topographic and hydrogeological models and to set up the initial and boundary conditions. Hydraulic properties are considered to be dominated by various factors of fracture (i.e. width, density, network) in the crystalline rock. Investigated was relationship between the hydraulic conductivity. which is one of important factors for evaluation of groundwater flow, and the fracture properties, using the method of multivariate analysis such as multiple regression analysis and cluster analysis. A total of 56 data on hydraulic conductivity and physical parameter were used that had been obtained from 2 boreholes drilled in the granitic rock of Tono area, Gifu, in the central Japan. The results are as follows: (1)The results of these two multivariate analysis are almost consistent. The hydraulic conductivity in the granitic rock is dominated by fracture system, such as number and width of the fracture, fissure-filling minerals. (2)The classificatory structure which obtained from the cluster analysis corresponds to that from hydraulic conductivity. Different hydraulic conductivities were distributed in each cluster that is dominated by width of open fracture, filling minerals, number of intersect and predominant direction of fractures. (3)The cluster analysis also implies that fracture properties of test sections with the similar hydraulic conductivities occasionally differ among them. Hence, the classifications is must be made based on the data of fracture properties as well as hydraulic conductivities. Future studies using sufficient number of data is necessary.

Study on chemical reactivity control of liquid sodium; Development of nano-particles production by flash evaporation

Saito, Junichi; Ara, Kuniaki; Fukunaga, Koichi*; Ogata, Kan*; Nagai, Masahiko*; Oka, Nobuki*; Kitagawa, Hiroshi*; Yamauchi, Miho*

no journal, , 

no abstracts in English

Measurements of residual stress distribution on peened nickel-based superalloy at cryogenic temperatures

Miyashita, Daisuke*; Akita, Koichi*; Oya, Shinichi*; Ono, Yoshinori*; Ogata, Toshio*; Yuri, Tetsumi*; Shobu, Takahisa

no journal, , 

no abstracts in English

Fabrication of metallic fuel elements for irradiation test at JOYO, 3, Fabrication of metallic fuel elements

Nakamura, Kinya*; Kikuchi, Hironobu; Ogata, Takanari*; Iwai, Takashi; Arai, Yasuo; Uozumi, Koichi*; Hijikata, Takatoshi*; Koyama, Tadafumi*; Itagaki, Wataru; Soga, Tomonori

no journal, , 

Irradiation test of metallic fuel elements at fast test reactor JOYO is planned. By the development of fabrication technique of casting, structure, analysis and inspection, metallic fuel elements were fabricated. In this paper, the structure technique is reported. Thermal bond (Na), element insulator and fuel slug were filled in PNC-FMS cladding, and upper plug was welded. Sodium bonding treatment was performed by shaking the fuel element under heating. By inspection, it was confirmed that the specification were satisfied.

Development of metal-coated zircaloy for accident tolerant fuel, 2; Materials development and radiation effects

Kano, Sho*; Murakami, Kenta*; Yang, H.*; Takanabe, Kazuhiro*; Nakayama, Akira*; Chen, Y.*; Yamaguchi, Masatake; Shinohara, Yasunari*; Ogata, Koichi*; Abe, Hiroaki*

no journal, , 

no abstracts in English