Annual report on the environmental radiation monitoring around the Tokai Reprocessing Plant FY2019

Nakano, Masanao; Fujii, Tomoko; Nemoto, Masashi; Tobita, Keiji; Seya, Natsumi; Nishimura, Shusaku; Hosomi, Kenji; Nagaoka, Mika; Yokoyama, Hiroya; Matsubara, Natsumi; et al.

JAEA-Review 2020-069, 163 Pages, 2021/02

JAEA-Review-2020-069.pdf:4.78MB

Environmental radiation monitoring around the Tokai Reprocessing Plant has been performed by the Nuclear Fuel Cycle Engineering Laboratories, based on "Safety Regulations for the Reprocessing Plant of Japan Atomic Energy Agency, Chapter IV - Environmental Monitoring". This annual report presents the results of the environmental monitoring and the dose estimation to the hypothetical inhabitant due to the radioactivity discharged from the plant to the atmosphere and the sea during April 2019 to March 2020. In this report, some data include the influence of the accidental release from the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Co., Inc. (the trade name was changed to Tokyo Electric Power Company Holdings, Inc. on April 1, 2016) in March 2011. Appendices present comprehensive information, such as monitoring programs, monitoring methods, monitoring results and their trends, meteorological data and discharged radioactive wastes. In addition, the data which were influenced by the accidental release and exceeded the normal range of fluctuation in the monitoring, were evaluated.

Annual report on the environmental radiation monitoring around the Tokai Reprocessing Plant FY2017

Nakano, Masanao; Fujita, Hiroki; Mizutani, Tomoko; Nemoto, Masashi; Tobita, Keiji; Kono, Takahiko; Hosomi, Kenji; Hokama, Tomonori; Nishimura, Tomohiro; Matsubara, Natsumi; et al.

JAEA-Review 2018-025, 171 Pages, 2019/02

JAEA-Review-2018-025.pdf:3.81MB

Environmental radiation monitoring around the Tokai Reprocessing Plant has been performed by the Nuclear Fuel Cycle Engineering Laboratories, based on "Safety Regulations for the Reprocessing Plant of Japan Atomic Energy Agency, Chapter IV - Environmental Monitoring". This annual report presents the results of the environmental monitoring and the dose estimation to the hypothetical inhabitant due to the radioactivity discharged from the plant to the atmosphere and the sea during April 2016 to March 2017. In this report, some data include the influence of the accidental release from the Fukushima Daiichi Nuclear Power Station of Electric Power Company Holdings, Inc. in March 2011. Appendices present comprehensive information, such as monitoring programs, monitoring methods, monitoring results and their trends, meteorological data and discharged radioactive wastes. In addition, the data which were influenced by the accidental release and were exceeded the normal range of fluctuation in the monitoring, were evaluated.

An in situ Mssbauer study using synchrotron radiation

Masuda, Ryo; Mitsui, Takaya; Ito, Keiji*; Sakaki, Koji*; Enoki, Hirotoshi*; Nakamura, Yumiko*; Seto, Makoto

Hyperfine Interactions, 204(1-3), p.139 - 142, 2012/03

https://doi.org/10.1007/s10751-011-0470-x

We have been developing a system for in situ Mssbauer studies using synchrotron radiation (SR) to elucidate the mechanism of hydrogenation processes. In the system, samples reacts in an atmosphere chamber and SR-based Mssbauer spectra using variable-frequency nuclear monochromator and energy spectra of inelastic nuclear resonant scattering (NRS) of SR are measured. As a feasibility study, the temperature dependence of the Mssbauer and inelastic NRS spectra of Fe in -GdFeH under vacuum were measured. In both spectra, clear differences were observed between 373 K and 573 K. These differences can be interpreted by the change of microscopic environment around Fe at the dehydrogenation. Thus, it is confirmed that this system works well enough to perform the in-situ Mssbauer study on the dehydrogenation of -GdFeH.

Laser-induced fluorescence and infrared spectroscopic studies on the specific solvation of tris(1-(2-thienyl)-4,4,4-trifluoro-1,3-butanedionato)europium(III) in an ionic liquid

Okamura, Hiroyuki; Sakae, Hiroki*; Kidani, Keiji*; Hirayama, Naoki*; Aoyagi, Noboru; Saito, Takumi*; Shimojo, Kojiro; Naganawa, Hirochika; Imura, Hisanori*

Polyhedron, 31(1), p.748 - 753, 2012/01

https://doi.org/10.1016/j.poly.2011.10.031

Hexafluoro complex of rutherfordium in mixed HF/HNO solutions

Toyoshima, Atsushi; Haba, Hiromitsu*; Tsukada, Kazuaki; Asai, Masato; Akiyama, Kazuhiko*; Goto, Shinichi*; Ishii, Yasuo; Nishinaka, Ichiro; Sato, Tetsuya; Nagame, Yuichiro; et al.

Radiochimica Acta, 96(3), p.125 - 134, 2008/03

https://doi.org/10.1524/ract.2008.1474

Formation of an anionic fluoride-complex of element 104, rutherfordium (Rf) produced in the Cm(O,5n)Rf reaction was studied by an anion-exchange method based on an atom-at-a-time scale. It was found that the hexafluoro complex of Rf, [RfF], was formed in the studied fluoride ion concentrations of 0.0005 - 0.013 M. Formation of [RfF] was significantly different from that of the homologues Zr and Hf, [ZrF] and [HfF]; the evaluated formation constant of [RfF] is at least one-order of magnitude smaller than those of [ZrF] and [HfF].

Relation between high ionic conductivity and boson peak in superionic glass

Arai, Masatoshi; Iwase, Hiroki; Nakamura, Mitsutaka; Otomo, Toshiya*; Kartini, E.*; Ito, Keiji*; Levett, S. J.*; Bennington, S. M.*

AIP Conference Proceedings 832, p.299 - 302, 2006/05

https://doi.org/10.1063/1.2204511

no abstracts in English

Conceptual study of transmutation experimental facility, 2; Study on ADS target test facility

Sasa, Toshinobu; Umeno, Makoto*; Mizubayashi, Hiroshi*; Mori, Keijiro*; Futakawa, Masatoshi; Saito, Shigeru; Kai, Tetsuya; Nakai, Kimikazu*; Zako, Akira*; Kasahara, Yoshiyuki*; et al.

JAERI-Tech 2005-021, 114 Pages, 2005/03

JAERI-Tech-2005-021.pdf:9.66MB

To perform the research and development for accelerator-driven system (ADS), Japan Atomic Energy Research Institute (JAERI) plans to build a Transmutation Experimental Facility under the JAERI-KEK joint J-PARC program. Transmutation Experimental Facility consists of two buildings, Transmutation Physics Experimental Facility to make reactor physics experiment with subcritical core, and ADS Target Test Facility for the preparation of irradiation database for various structural materials. In this report, purpose to build, experimental schedule, and design study of the ADS target test facility with drawer type spallation target are summarized.

Analytical Assessment of Full-Scale Demonstration of Sealing Technique in Canadian Geological Disposal Facility

Toida, Masaru*; Sasakura, Takeshi*; Atsumi, Hiroyuki*; Suyama, Yasuhiro*; Kobayashi, Ichizo*; Kawabata, Junichi*; Ito, Keijiro*

JNC TJ8400 2003-088, 254 Pages, 2004/02

JNC-TJ8400-2003-088.pdf:9.59MB

To establish sealing technique suitable for geological environmental conditions of Japan, it is necessary to obtain data related with this sealing function through laboratory tests and in-situ tests. It also is necessary to put these data to practical use and to establish the estimating method of the sealing technique. Tunnnel sealing experiment, which has been carried out as a joint research between JNC and AECL at URL of AECL Canada, is arriving the final stage and fundamental data relating with the sealing function has almost obtained. This report deals with the total data processing and interpretation of the sealing test, as well as the numerical analysis and interpretation on tracer test results. Concrete plans for the disassembling and sampling of clay and concrete plugs, which is important for the evaluation of function of the sealing system, is also discussed.

Recent activities of Pb-Bi technology for ADS at JAERI

Kikuchi, Kenji; Saito, Shigeru; Kurata, Yuji; Futakawa, Masatoshi; Sasa, Toshinobu; Oigawa, Hiroyuki; Umeno, Makoto*; Mori, Keijiro*; Takano, Hideki; Wakai, Eiichi

Proceedings of 11th International Conference on Nuclear Engineering (ICONE-11) (CD-ROM), 7 Pages, 2003/04

In order to construct ADS Target Test facility in J-PARC project the research and development on Pb-Bi technology have been carried, which cover target design with computer simulation, flowing loop test, stagnant corrosion test, oxygen sensor and cleaning techniques. Obtained results are as follows: Corrosion rate of SUS316 under flowing Pb-Bi at 1m/s at 450C is 0.1 mm / 3000 hrs. Fe and Cr were melted into lead bismuth from SS316 in the high temperature part and deposited in the low-temperature part according to the difference of solubility. The corrosion thickness decreases with increasing Cr content in the stagnant corrosion test at saturated oxygen concentration. Reliable oxygen sensors are to be developed by using suitable reference electrodes. As a result of cleaning tests, blushing process was needed to remove Pb-Bi effectively after immersion in the silicon oil. The mixed acid easily dissolved Pb-Bi and removed almost perfectly. But specimens themselves were affected by coloring.

Full-scale Demonstration of Sealing Technique in Geological Disposal(III)

Toida, Masaru*; Shiogama, Yukihiro*; Atsumi, Hiroyuki*; Suyama, Yasuhiro*; Kawabata, Junichi*; Ito, Keijiro*; Okutsu, Kazuo*

JNC TJ8400 2003-022, 213 Pages, 2003/01

JNC-TJ8400-2003-022.pdf:13.05MB

To establish sealing technique suitable for geological environmental conditions of Japan, it is necessary to obtain data related with this sealing function through laboratory tests and in-situ tests. It also is necessary to put these data to practical use and to establish the estimating method of the sealing technique. This report deals with the sealing function tests under heating condition of supplying water, following the pressurized tests of supplying water at the AECL in Canada until last year. These test results are reported here together with the data, interpretation and analysis of tracer test results. Information arrangement for the establishment of estimation method of sealing function is also performed.