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Tobita, Minoru*; Haraga, Tomoko; Endo, Tsubasa*; Omori, Hiroyuki*; Mitsukai, Akina; Aono, Ryuji; Ueno, Takashi; Ishimori, Kenichiro; Kameo, Yutaka
JAEA-Data/Code 2021-013, 30 Pages, 2021/12
JAEA-Data-Code-2021-013.pdf:1.47MB
Radioactive wastes generated from nuclear research facilities in Japan Atomic Energy Agency are planning to be buried in the near surface disposal field. Therefore, it is required to establish the method to evaluate the radioactivity concentrations of radioactive wastes until the beginning of disposal. In order to contribute to this work, we collected and analyzed concrete samples generated from JPDR facility. In this report, we summarized the radioactivity concentrations of 21 radionuclides (
H, 
C, 
Cl, 
Ca, 
Co, 
Ni, 
Sr, 
Nb, 
Ag, 
Cs, 
Eu, 
Eu, 
Ho, 
U, 
U, Pu, 
Pu, 
Pu, 
Am, 
Am, 
Cm) which were obtained from radiochemical analysis of the samples in fiscal year 2018-2019.
Zr, Mo, 
Pd and 
Sn analytical methods for radioactive waste from Fukushima Daiichi Nuclear Power StationAono, Ryuji; Sato, Yoshiyuki; Shimada, Asako; Tanaka, Kiwamu; Ueno, Takashi; Ishimori, Kenichiro; Kameo, Yutaka
JAEA-Technology 2017-025, 32 Pages, 2017/11
JAEA-Technology-2017-025.pdf:1.45MB
We have developed analytical methods for Zr, Mo, Pd and Sn, which are considered important in terms of the safety assessment of radioactive waste disposal. The methods are specialized for the wastes left after Fukushima accident. As the main analytical sample, we assumed accumulated water / treated water collected at Fukushima Daiichi Nuclear Power Station. As for Zr, Mo, Pd and Sn contained in this accumulated water / treated water, we have worked on the development of separation and purification method of target nuclide and improvement of recovery, and summarized these results in this report.
Sato, Yoshiyuki; Aono, Ryuji; Konda, Miki; Tanaka, Kiwamu; Ueno, Takashi; Ishimori, Kenichiro; Kameo, Yutaka
Proceedings of 54th Annual Meeting of Hot Laboratories and Remote Handling (HOTLAB 2017) (Internet), 13 Pages, 2017/00
no abstracts in English
Sato, Yoshiyuki; Tanaka, Kiwamu; Ueno, Takashi; Ishimori, Kenichiro; Kameo, Yutaka
Hoken Butsuri, 51(4), p.209 - 217, 2016/12
A large amount of contaminated rubbles were generated by the accident at the Fukushima Daiichi Nuclear Power Station (F1NPS). For safe decommissioning of F1NPS, it is important to evaluate the composition and concentration of radionuclides in the rubbles. In this paper, to characterize the rubbles collected at F1NPS in Unit-1, Unit-2 and Unit-3, radiochemical analysis was operated. As a result of radiochemical analysis, 
-ray-emitting nuclides Co, Cs and 
Eu, 
-ray-emitting nuclides H, C, Sr and 
Tc, and 
-particle-emitting nuclides 
Pu, Am and Cm were detected. In contrast, Nb and Eu concentrations were below the detection limit. Measured radioactive concentrations implied that H, C, Co and Sr concentrations depended on Cs concentration respectively. This analysis was characterized the radioactivity concentrations of the rubbles.
Noguchi, Yuto; Maruyama, Takahito; Ueno, Kenichi; Komai, Masafumi; Takeda, Nobukazu; Kakudate, Satoshi
Fusion Engineering and Design, 109-111(Part B), p.1291 - 1295, 2016/11
Times Cited Count：2 Percentile：19.71(Nuclear Science & Technology)This paper reports the impact hammer test of the full-scale mock-up of ITER Blanket Remote Handling system (BRHS). Since the BRHS, which is composed of the articulated rail and the vehicle manipulator which travels on the rail deployed in the vacuum vessel, is subjected to the floor response spectrum with 14 G peak at 8 Hz, evaluation of dynamic response of the system is of essential importance. Recently impact hammer testing on the full-scale mock-up of the BRHS was carried out to verify the finite element method seismic analysis and to experimentally obtain the damping ratio of the system. The results showed that the mock-up has a vertical major natural mode with a natural frequency of 7.5 Hz and a damping ratio of 0.5%. While higher structural damping ratios is predicted in a high amplitude excitation such as major earthquake, it was confirmed that the experimental natural major frequencies are in agreement with the major frequencies obtained by elastic dynamic analysis.
Seki, Kotaro; Sasaki, Takayuki*; Akimoto, Yuji*; Tokunaga, Takahito; Tanaka, Kiwamu; Haraga, Tomoko; Ueno, Takashi; Ishimori, Kenichiro; Hoshi, Akiko; Kameo, Yutaka
JAEA-Technology 2016-013, 37 Pages, 2016/07
JAEA-Technology-2016-013.pdf:2.09MB
In this study, based on the simple and rapid analytical method established from the wastes from research facilities, we created analytical schemes which is applicable to rubble and plants collected at Fukushima Daiichi, then transported to Nuclear Science Research Institute of JAEA. We examined the applicability, and confirmed quantifiability of radioactivity concentration with high recovery rate without being affected by fission products such as Sr and Cs.
Moriyama, Setsuko; Ueno, Kenichi
Purazuma, Kaku Yugo Gakkai-Shi, 91(1), p.74 - 75, 2015/01
no abstracts in English
Moriyama, Setsuko; Ueno, Kenichi; Neyatani, Yuzuru
Purazuma, Kaku Yugo Gakkai-Shi, 90(11), p.750 - 751, 2014/11
no abstracts in English
Saito, Makiko; Ueno, Kenichi; Maruyama, Takahito; Murakami, Shin; Takeda, Nobukazu; Kakudate, Satoshi; Nakahira, Masataka*; Tesini, A.*
Fusion Engineering and Design, 89(9-10), p.2352 - 2356, 2014/10
Times Cited Count：8 Percentile：53.31(Nuclear Science & Technology)After plasma operation of the ITER reactor, irradiated radioactive dust will accumulate in the vacuum vessel (VV). The In Vessel Transporter (IVT) will be installed in the VV and remove the blanket modules for maintenance. The IVT will be carried back to the Hot Cell Facilities (HCF) after exchanging the blanket, and the IVT itself also needs maintenance. It is considered that the maintenance workers will be exposed to the irradiated radioactive dust attached to the IVT surface. In this study, dust contamination of the IVT is evaluated to assess exposure during maintenance work in the HCF. The IVT contamination scenario is assumed in the ITER project. From plasma shut down until maintenance is performed on the IVT will take 345 days under the ITER project assumption. Under this scenario, the effective dose rate from irradiated radioactive dust was calculated as an infinite plate for each nuclide. As a result, W-181 and Ta-182 were the dominant nuclides for the effective dose rate. If all dust is W-181 or Ta-182, the effective dose rate is about 400 
Sv/h and 100 Sv/h respectively. Nevertheless, using the dose limit determined by the ITER project and the estimated maximum maintenance time, the effective dose rate limit was calculated to be 4.18 Sv/h under these limited conditions. To satisfy the dose rate limit, decontamination processes were assumed and the dose rate after decontamination was evaluated.
Moriyama, Setsuko; Neyatani, Yuzuru; Ueno, Kenichi
Purazuma, Kaku Yugo Gakkai-Shi, 90(9), p.577 - 578, 2014/09
no abstracts in English
Moriyama, Setsuko; Neyatani, Yuzuru; Ueno, Kenichi
Purazuma, Kaku Yugo Gakkai-Shi, 90(7), p.429 - 430, 2014/07
no abstracts in English
Moriyama, Setsuko; Neyatani, Yuzuru; Ueno, Kenichi
Purazuma, Kaku Yugo Gakkai-Shi, 90(3), p.198 - 199, 2014/03
no abstracts in English
Ueno, Kenichi; Aburadani, Atsushi; Saito, Makiko; Maruyama, Takahito; Takeda, Nobukazu; Murakami, Shin; Kakudate, Satoshi
Plasma and Fusion Research (Internet), 9, p.1405012_1 - 1405012_4, 2014/02
Moriyama, Setsuko; Neyatani, Yuzuru; Ueno, Kenichi
Purazuma, Kaku Yugo Gakkai-Shi, 90(1), p.86 - 87, 2014/01
no abstracts in English
Moriyama, Setsuko; Ueno, Kenichi; Neyatani, Yuzuru
Purazuma, Kaku Yugo Gakkai-Shi, 89(11), p.820 - 821, 2013/11
no abstracts in English
Moriyama, Setsuko; Neyatani, Yuzuru; Ueno, Kenichi
Purazuma, Kaku Yugo Gakkai-Shi, 89(9), P. 637, 2013/09
no abstracts in English
Moriyama, Setsuko; Ueno, Kenichi; Neyatani, Yuzuru
Purazuma, Kaku Yugo Gakkai-Shi, 89(7), p.509 - 510, 2013/07
no abstracts in English
Ueno, Kenichi; Matsui, Kunihiro; Nishino, Toru; Isono, Takaaki; Okuno, Kiyoshi
Plasma and Fusion Research (Internet), 8(Sp.1), p.2405062_1 - 2405062_5, 2013/05
Japan Domestic Agency (JADA) for ITER will procure toroidal field (TF) coil structures and winding packs, and assemble them into a final TF coil configuration. Because the manufacturing schedule of the TF coils is on a critical path toward the first plasma of ITER, coil manufacturing must be successful and proceed on schedule. Therefore, risk assessment and management for the manufacturing are vital. JADA performed a risk assessment on the basis of past manufacturing experiences and risk mitigation policy for ITER. The results show that risks can be mitigated to a level that we can assure sufficint quality of the TF coil by sound design, manufacturing and quality management processes developed through R&D activities, and the use of prototypes.
Moriyama, Setsuko; Ueno, Kenichi; Neyatani, Yuzuru
Purazuma, Kaku Yugo Gakkai-Shi, 89(5), P. 328, 2013/05
no abstracts in English
Nisawa, Atsushi*; Yoneda, Yasuhiro; Ueno, Go*; Murakami, Hironori*; Okajima, Yuka*; Yamamoto, Kenichiro*; Semba, Yasunori*; Uesugi, Kentaro*; Tanaka, Yoshihito*; Yamamoto, Masaki*; et al.
Journal of Synchrotron Radiation, 20(2), p.219 - 225, 2013/03
Times Cited Count：12 Percentile：54.28(Instruments & Instrumentation)A Si(111) winged crystal has been designed to minimize anticlastic bending and improve sagittal focusing efficiency. The crystal was thin with wide stiffening wings. The length-to-width ratio of the crystal was optimized by finite element analysis, and the optimal value was larger than the "golden value". The analysis showed that the slope error owing to anticlastic bending is less than the Darwin width. The X-rays were focused two-dimensionally using the crystal and a tangentially bent mirror. The observed profiles of the focal spot agreed well with the results of a ray-tracing calculation in the energy range from 8 to 17.5 keV. X-ray diffraction measurements with a high signal-to-noise ratio using this focusing system were demonstrated for a small protein crystal.
