Development of -ray visualization survey meter in high gamma and neutron background environment

Tsubota, Yoichi; Kobayashi, Kenji; Ishii, Tatsuya; Hirato, Misaki; Shioya, Satoshi; Nakagawa, Takahiro

Radiation Protection Dosimetry, 200(16-18), p.1676 - 1680, 2024/11

https://doi.org/10.1093/rpd/ncae169

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 2.110 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.

Structural and compositional characteristics of Fukushima release particulate material from Units 1 and 3 elucidates release mechanisms, accident chronology and future decommissioning strategy

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

https://doi.org/10.1038/s41598-020-79169-2

Hydraulic tests using borehole PB-V01 in the Horonobe Underground Research Project

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.

Wetting induced oxidation of Pt-based nano catalysts revealed by high energy resolution X-ray absorption spectroscopy

Cui, 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

https://doi.org/10.1038/s41598-017-00639-1

Adsorption behaviors of platinum group metals in simulated high level liquid waste using macroporous (MOTDGA-TOA)/SiO-P silica-based absorbent

Ito, Tatsuya; Kim, S.-Y.*; Xu, Y.*; Hitomi, Keitaro*; Ishii, Keizo*; Nagaishi, Ryuji; Kimura, Takaumi

Separation Science and Technology, 48(17), p.2616 - 2625, 2013/10

https://doi.org/10.1080/01496395.2013.807290

As fundamental research for separation of platinum group metals (PGMs) from high level liquid waste (HLLW) by macroporous silica-based adsorbent, (MOTDGA-TOA)/SiO-P adsorbent was prepared by impregnation of N,N'-dimethyl-N,N'-di-noctyl-thiodiglycolamide (MOTDGA) and Tri-n-octylamine (TOA) into silica/polymer composite support (SiO-P). The adsorption behavior of Ru(III), Rh(III), and Pd(II) in simulated HLLW onto the adsorbent were investigated by the batch method to obtain their corresponding equilibrium and kinetic data. The adsorbent showed strong adsorption for Pd(II) and the adsorption reached equilibrium within 2 hr. In addition, the use of both MOTDGA and TOA improved adsorption of Ru(III) and Rh(III) better than individual use of them. The adsorptions of Ru(III), Rh(III), and Pd(II) followed the Langmuir adsorption model, and were found to be controlled by the chemisorption mechanism.

Production of no-carrier-added Cu and applications to molecular imaging by PET and PETIS as a biomedical tracer

Watanabe, 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

https://doi.org/10.1007/s10967-008-7443-9

Studies on PGMs adsorption and radiation resistance of macroporous (MOTDGA-TOA)/SiO-P silica-based absorbent under -ray irradiation

Ito, Tatsuya; Nagaishi, Ryuji; Kim, S.-Y.*; Xu, Y.*; Hitomi, Keitaro*; Ishii, Keizo*; Kimura, Takaumi

no journal, , 

no abstracts in English

Detection and measurement of abnormal posture under stressful conditions in nematode

Ide, Kazunori*; Ishikawa, Tomoya*; Arai, Shingo*; Morioka, Tatsuya*; Kaneda, Hiroki*; Suzuki, Michiyo; Sakashita, Tetsuya; Ishii, Naoaki*; Yanase, Sumino*

no journal, , 

Production of Cu as a biotracer and applications to in vivo imaging of Cu in a plant

Watanabe, 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.

Research and development of the "SELECT process" for Actinide separation

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