Establishment of characterization method for small fuel debris using the world's first isotope micro imaging apparatus (Contract research); FY2023 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Kogakuin University*

JAEA-Review 2025-013, 111 Pages, 2025/10

JAEA-Review-2025-013.pdf:7.49MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2023. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2021, this report summarizes the research results of the "Establishment of characterization method for small fuel debris using the world's first isotope micro imaging apparatus" conducted from FY2021 to FY2023. The present study aims to obtain, for the first time in the world, the important data necessary for clarifying the retrieval of small amounts of fuel debris, and to evaluate and examine them. The isotope microimaging apparatus (developed by Kogakuin University) introduced at the JAEA Fuel Monitoring Facility (FMF) can obtain local quantitative data such as isotope composition while processing cross-sections of radioactive micro-samples, which can be used to determine the properties of fuel debris. In FY2021, we improved the isotope microimaging apparatus introduced to the JAEA FMF to accommodate high radiation dose samples. In FY2022, we maintained the isotope microimaging apparatus at the JAEA FMF and succeeded in analyzing real particles containing uranium. In FY2023, we completed development to automate and remotely perform analysis routines using a prototype machine at Kogakuin University. At the JAEA FMF, although manual operations were involved, we succeeded in analyzing each Cs isotope from real particles by resonance ionization. In Nagoya University, we improved the RIMS apparatus to investigate the difference in electronic state caused by ion beam sputtering. And we succeeded in obtaining resonance ionization signals from neutral particles generated by ion beam sputtering. At the JAEA CLADS, they investigated the ionization scheme for important nuclides Nd and Gd. Those proposed ionization schemes were examined at Kogakuin University.

Establishment of characterization method for small fuel debris using the world's first isotope micro imaging apparatus (Contract research); FY2022 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Kogakuin University*

JAEA-Review 2024-015, 99 Pages, 2024/09

JAEA-Review-2024-015.pdf:5.42MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2022. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2021, this report summarizes the research results of the "Establishment of characterization method for small fuel debris using the world's first isotope micro imaging apparatus" conducted in FY2022. The present study aims to obtain, for the first time in the world, the important data necessary for clarifying the retrieval of small amounts of fuel debris, and to evaluate and examine them. SEM-EDS and TEM-EDS cannot be used for isotopic identification and analysis of Pu and B. On the other hand, bulk analysis such as ICP-MS lacks the information in a micro region.

Uranium particle identification with SEM-EDX for isotopic analysis by secondary ion mass spectrometry

Esaka, Fumitaka; Magara, Masaaki

Mass Spectrometry Letters, 7(2), p.41 - 44, 2016/06

https://doi.org/10.5478/MSL.2016.7.2.41

Secondary ion mass spectrometry (SIMS) is a promising tool to measure isotope ratios of individual uranium particles in environmental samples for nuclear safeguards. However, the analysis requires prior identification of a small number of uranium particles that coexist with a large number of other particles without uranium. In the present study, this identification was performed by scanning electron microscopy -energy dispersive X-ray analysis with automated particle search mode. The analytical results for an environmental sample taken at a nuclear facility indicated that the observation of backscattered electron images with 1000 magnification was appropriate to efficiently identify uranium particles. Lower magnification (less than 500) made it difficult to detect smaller particles of approximately 1 m diameter.

Development of analytical techniques for safeguards environmental samples

Magara, Masaaki; Usuda, Shigekazu; Sakurai, Satoshi; Watanabe, Kazuo; Esaka, Fumitaka; Hirayama, Fumio; Lee, C. G.; Yasuda, Kenichiro; Kono, Nobuaki; Inagawa, Jun; et al.

Dai-26-Kai Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Nenji Taikai Rombunshu, p.157 - 164, 2005/00

JAERI has conducted the analysis of domestic and the IAEA samples. JAERI is developing the analytical techniques to improve the analytical ability for the safeguards environmental samples. For bulk analysis, study is focused on the improvement of reliability of isotope ratio measurements by ICP-MS. New chemical separation techniques are under development and a desolvation module is introduced to reduce the polyatomic interferences. In particle analysis, the sample preparation procedure for SIMS method is modified to measure the U/U and U/U ratios for individual particles. We are also developing fission track-TIMS method to measure uranium isotope ratios in particles of sub-micrometer size. A screening instrument of X-ray fluorescent analysis is equipped to measure elemental distribution on a swipe surface.

Mechanical properties and microstructure of F82H steel doped with boron or boron and nitrogen as a function of heat treatment

Wakai, Eiichi; Sato, Michitaka*; Sawai, Tomotsugu; Shiba, Kiyoyuki; Jitsukawa, Shiro

Materials Transactions, 45(2), p.407 - 410, 2004/01

https://doi.org/10.2320/matertrans.45.407

no abstracts in English

SIMS analyses of SiO/4H-SiC(0001) interface

Yamashita, Kenya*; Kitabatake, Makoto*; Kusumoto, Osamu*; Takahashi, Kunimasa*; Uchida, Masao*; Miyanaga, Ryoko*; Ito, Hisayoshi; Yoshikawa, Masahito

Materials Science Forum, 389-393, p.1037 - 1040, 2002/00

https://doi.org/10.4028/www.scientific.net/MSF.389-393.1037

no abstracts in English

Development of analytical techniques for ultra trace amounts of nuclear materials in environmental samples using ICP-MS for safeguards

Magara, Masaaki; Hanzawa, Yukiko; Esaka, Fumitaka; Miyamoto, Yutaka; Yasuda, Kenichiro; Watanabe, Kazuo; Usuda, Shigekazu; Nishimura, Hideo; Adachi, Takeo

Applied Radiation and Isotopes, 53(1-2), p.87 - 90, 2000/07

https://doi.org/10.1016/S0969-8043(00)00117-2

no abstracts in English

SIMS analysis of lead isotopes in the primary ore body of the Koongarra deposit, Australia; Behavior of lead in the alteration of uranium minerals

Isobe, Hiroshi; Hidaka, Hiroshi*; Onuki, Toshihiko

Mat. Res. Soc. Symp. Proc., 506, p.687 - 694, 1998/00

no abstracts in English

Thin film growth by low energy hydrocarbon ion deposition

; Aoki, Yasushi; Nagai, Shiro

Dai-4-Kai Ryushisen No Sentanteki Oyo Gijutsu Ni Kansuru Shimpojiumu, p.175 - 178, 1993/00

no abstracts in English

Surface chemical changes of TiC,TiN and TiO by light-ion bombardments

;

Journal of Nuclear Materials, 145-147, p.396 - 400, 1987/00

https://doi.org/10.1016/0022-3115(87)90368-0

no abstracts in English