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-ray visualization survey meter in high gamma and neutron background environmentTsubota, Yoichi; Kobayashi, Kenji; Ishii, Tatsuya; Hirato, Misaki; Shioya, Satoshi; Nakagawa, Takahiro
Radiation Protection Dosimetry, 200(16-18), p.1676 - 1680, 2024/11
Times Cited Count：0 Percentile：0.00(Environmental Sciences)In the decommissioning of the Fukushima Daiichi Nuclear Power Station (FDNPS, 1F), workers are removing structures from inside the buildings, monitoring radioactive contamination, and decontaminating inside the buildings. For the measurement of contamination of suit surfaces of workers, we have developed a hand-held survey meter that can measure and visualize surface radioactive contamination of -nuclides in a high 
/ 
-ray background environment. In order to selectively measure -nuclides, we designed and built a prototype hand-held survey meter for -rays, which consists of a thin-film ZnS:Ag scintillator, a multi-anode photomultiplier tube (MA-PMT), individual amplification and counting circuits for each channel of the MA-PMT. Based on the result of -ray counting, the developed device is capable of counting the -radiation beyond 2.1
10
cpm. In the -ray response test, there was no -ray response even when the detector was in close proximity to a high intensity source; The dose rate was estimated to be more than 1 Sv/h. In the future, we plan to reduce the weight and size of the device, as well as improve the usability of the device through actual testing in contaminated environments.
Shimazaki, Yosuke; Jidaisho, Tatsuya; Ishii, Toshiaki; Inoi, Hiroyuki; Iigaki, Kazuhiko
JAEA-Technology 2024-005, 23 Pages, 2024/06
JAEA-Technology-2024-005.pdf:5.53MB
HTTR has newly assumed Beyond Design Basis Accident (BDBA) as part of conformity assessment with the new regulatory standards and has established measures to prevent the spread of BDBA. Among these measures, to prevent the spread of BDBA caused by cooling water leaks from spent fuel storage pool, the Oarai Research Institute's fire engine was selected as an equipment to prevent the spread of BDBA, and required performances such as pumping water performance were determined. After all required performances were confirmed by inspections, the fire engine passed the operator's pre-use inspection and contributed to the restart of the HTTR operations.
Martin, P. G.*; Jones, C. P.*; Bartlett, S.*; Ignatyev, K.*; Megson-Smith, D.*; Satou, Yukihiko; Cipiccia, S.*; Batey, D. J.*; Rau, C.*; Sueki, Keisuke*; et al.
Scientific Reports (Internet), 10, p.22056_1 - 22056_17, 2020/12
Times Cited Count：4 Percentile：19.72(Multidisciplinary Sciences)Martin, P. G.*; Jones, C. P.*; Cipiccia, S.*; Batey, D. J.*; Hallam, K. R.*; Satou, Yukihiko; Griffiths, I.*; Rau, C.*; Richards, D. A.*; Sueki, Keisuke*; et al.
Scientific Reports (Internet), 10(1), p.1636_1 - 1636_11, 2020/01
Times Cited Count：9 Percentile：30.72(Multidisciplinary Sciences)Samata, Yoichi; Iwata, Tatsuya*; Ishii, Eiichi
JAEA-Data/Code 2019-008, 19 Pages, 2019/09
JAEA-Data-Code-2019-008.pdf:2.82MB
JAEA-Data-Code-2019-008-appendix(CD-ROM).zip:1.38MB
In Horonobe Underground Research Laboratory Project, hydraulic tests for the excavation damaged zone have been performed in order to characterize the hydrological properties of the zone. In PB-V01 borehole, pore pressure observation started in October 2008, but the pore pressure is currently reduced by about 3 MPa compared to that time. In this report, in order to evaluate the influence that this pore pressure drop has on the permeability of the rock, the results of the in-situ permeability test using the long-term hydraulic pressure monitoring device installed in the same hole are summarized.
Cui, Y.-T.*; Harada, Yoshihisa*; Niwa, Hideharu*; Oshima, Masaharu*; Hatanaka, Tatsuya*; Nakamura, Naoki*; Ando, Masaki*; Yoshida, Toshihiko*; Ishii, Kenji*; Matsumura, Daiju
NanotechJapan Bulletin (Internet), 11(4), 6 Pages, 2018/08
no abstracts in English
high energy resolution X-ray absorption spectroscopyCui, Y.-T.*; Harada, Yoshihisa*; Niwa, Hideharu*; Hatanaka, Tatsuya*; Nakamura, Naoki*; Ando, Masaki*; Yoshida, Toshihiko*; Ishii, Kenji*; Matsumura, Daiju; Oji, Hiroshi*; et al.
Scientific Reports (Internet), 7(1), p.1482_1 - 1482_8, 2017/05
Times Cited Count：21 Percentile：47.42(Multidisciplinary Sciences)
and O/HO adsorption revealed by in situ XAFS and hard X-ray photoelectron spectroscopyCui, Y.*; Harada, Yoshihisa*; Hatanaka, Tatsuya*; Nakamura, Naoki*; Ando, Masaki*; Yoshida, Toshihiko*; Ikenaga, Eiji*; Ishii, Kenji*; Matsumura, Daiju; Li, R.*; et al.
ECS Transactions, 72(8), p.131 - 136, 2016/10
Times Cited Count：1 Percentile：44.88(Electrochemistry)Sanada, Yukihisa; Ishii, Masato*; Hasegawa, Ichiro; Kanazawa, Nobuyuki; Chikazawa, Tatsuya*; Momose, Takumaro
NEA/CSNI/R(2010)4 (Internet), p.351 - 370, 2010/11
A criticality accident alarm system (CAAS) was installed in the 1980s as part of criticality safety management at the Tokai Reprocessing Plant (TRP) to reduce the chance of workers being exposed to radiation in the rare case of a criticality accident. From a compliance point of view processing at TRP cannot take place without the criticality monitoring provided by the CAAS. This paper gives an overview of the process of the CAAS being replaced as part of aging management.
Cu and applications to molecular imaging by PET and PETIS as a biomedical tracerWatanabe, Shigeki; Iida, Yasuhiko*; Suzui, Nobuo; Katabuchi, Tatsuya*; Ishii, Satomi; Kawachi, Naoki; Hanaoka, Hirofumi*; Watanabe, Satoshi; Matsuhashi, Shimpei; Endo, Keigo*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 280(1), p.199 - 205, 2009/04
Times Cited Count：25 Percentile：81.66(Chemistry, Analytical)Tsuji, Hiroshi; Okuno, Kiyoshi*; Thome, R.*; Salpietro, E.*; Egorov, S. A.*; Martovetsky, N.*; Ricci, M.*; Zanino, R.*; Zahn, G.*; Martinez, A.*; et al.
Nuclear Fusion, 41(5), p.645 - 651, 2001/05
Times Cited Count：58 Percentile：82.72(Physics, Fluids & Plasmas)no abstracts in English
Matsumura, Tatsuro; Ban, Yasutoshi; Suzuki, Hideya; Tsubata, Yasuhiro; Hotoku, Shinobu; Tsutsui, Nao; Suzuki, Asuka; Toigawa, Tomohiro; Kurosawa, Tatsuya*; Shibata, Mitsunobu*; et al.
no journal, ,
PUREX process was established for industrial scale reprocessing plant. TRUEX and the 4 group separation were developed for partitioning of minor actinides from HLW, and demonstrated using genuine HLW. Although the extractants for the processes have excellent performance, the molecules contain phosphorus which could be cause for the secondary waste from the solvent extraction processes. To minimize the radioactive waste, we have conducted research and development of the new reprocessing and MA separation processes using innovative extractants in accord with CHON principle. The extractants for reprocessing process are monoamides as alternative extractants for TBP. For An(III)+RE recovery process, we developed TDdDGA. HONTA and ADAAM were developed for An(III)/RE separation process and Am/Cm separation process respectively. The separation performances of the flowsheets were evaluated by continuous extraction tests using simulated and genuine spent fuel and high level liquid waste.
Matsumura, Tatsuro; Ban, Yasutoshi; Hotoku, Shinobu; Suzuki, Hideya; Tsubata, Yasuhiro; Tsutsui, Nao; Morita, Keisuke; Toigawa, Tomohiro; Shibata, Mitsunobu*; Kurosawa, Tatsuya*; et al.
no journal, ,
no abstracts in English
Satou, Yukihiko; Kobata, Masaaki; Okane, Tetsuo; Sueki, Keisuke*; Matsuo, Kazuki*; Ishii, Tatsuya*; Martin, P.*; Scott, T.*
no journal, ,
no abstracts in English
Matsumura, Tatsuro; Ban, Yasutoshi; Hotoku, Shinobu; Suzuki, Hideya; Tsubata, Yasuhiro; Tsutsui, Nao; Morita, Keisuke; Toigawa, Tomohiro; Shibata, Mitsunobu*; Kurosawa, Tatsuya*; et al.
no journal, ,
no abstracts in English
Cu as a biotracer and applications to in vivo imaging of Cu in a plantWatanabe, Shigeki; Ishioka, Noriko; Katabuchi, Tatsuya*; Watanabe, Satoshi; Suzui, Nobuo; Ishii, Satomi; Matsuhashi, Shimpei
no journal, ,
Positron emitter, Cu has been used in medical applications with positron emission tomography (PET). We have developed a novel method in Cu production to obtain Cu-labelled antibodies as a PET reagent. On the other hand, Cu can be used for in vivo imaging of copper in a living plant by positron emitting tracer imaging system (PETIS). Production of Cu was carried out via the Ni(p,n)Cu nuclear reaction. The produced Cu (330 MBq) was purified by an ion-exchange method from the irradiated NiO target. The Cu was obtained with high yield (89%) and high radionuclidic-purity Cu (
99%). The NiO was recovered in good yield ( 99%). The Cu was added to a plant (soybean) for an imaging experiment and the movement of Cu was visualized by the PETIS. This result shows that Cu can be applied as a useful tracer for not only medical applications and also plant physiological studies.
Satou, Yukihiko; Sueki, Keisuke*; Ishii, Tatsuya*; Igarashi, Junya*; Martin, P.*; Jones, C.*; Scott, T.*
no journal, ,
In Fukushima accident, insoluble radioactive Cs particles found at the northwestern region from the Fukushima Dai-ichi Nuclear Power Station (1FNPS). Presence of Cs particle in other surrounding area from 1FNPS is unclear yet. In the present study, the presence of other particle emission events and the presence of new types of radioactive particles were investigated by expanding the search object to soil samples collected outside the 1FNPS northwest region where insoluble Cs particles were reported. Four radioactive particles found from the samples. The particles look like pebbles and diameter is 0.4 to 2 mm, and the size feature is Type B. Isotopic ratio of Cs is very similar to type A of 1.0. EDS results confirmed the presence of iron and aluminum in addition to silicon. Further, in the CT image, there was an absorption point near the surface indicating that the element is heavier than iron. Although these features are clearly different from the insoluble Cs particles that have been reported in the past, in this implementation item it is not possible to find the location where Cs is adsorbed, and further direct emission from uranium or in the reactor.
Nakamura, Satoshi; Suzuki, Hideya*; Ishii, Sho*; Emori, Tatsuya; Kurosawa, Tatsuya*; Shibata, Mitsunobu*; Shimojo, Kojiro; Ban, Yasutoshi
no journal, ,
To reduce volume and radiotoxicity of high-level radioactive waste, JAEA has been developing a separation process called "SELECT" (Solvent Extraction from Liquid-waste using Extractants of CHON-type for Transmutation) for recovering minor actinides (MA) from high-level radioactive liquid-waste. In this study, the applicability of an acidic diamide-type extractant Branched-TetraOctylNitriloAceticAcidDiAmide (B-TONAADA) was investigated with a view to improving the efficiency of MA/Rare Earth Elements (RE) separation in SELECT process. As a results of extraction tests performed with different nitric acid concentrations, specific changes were observed in the lanthanide patterns of distribution ratios, and the distribution ratios of MA were higher than those of RE over a wide range of nitric acid concentrations.
Kobayashi, Kenji; Ishii, Tatsuya; Tsubota, Yoichi; Shioya, Satoshi; Ishibashi, Nauya; Nakagawa, Takahiro
no journal, ,
no abstracts in English
Ishii, Tatsuya; Kobayashi, Kenji; Tsubota, Yoichi; Shioya, Satoshi; Ishibashi, Nauya; Nakagawa, Takahiro
no journal, ,
no abstracts in English
