Residual stresses of small-bore butt-welded piping measured by quantum beam hybrid method

Suzuki, Kenji*; Miura, Yasufumi*; Toyokawa, Hidenori*; Shiro, Ayumi*; Shobu, Takahisa; Morooka, Satoshi; Shibayama, Yuki

Quantum Beam Science (Internet), 9(2), p.15_1 - 15_15, 2025/06

https://doi.org/10.3390/qubs9020015

Development of rapid and sensitive radionuclide analysis method by simultaneous analysis of , , and X-rays (Contract research); FY2022 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Japan Chemical Analysis Center*

JAEA-Review 2023-022, 93 Pages, 2023/12

JAEA-Review-2023-022.pdf:4.7MB

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 FY2020, this report summarizes the research results of the "Development of rapid and sensitive radionuclide analysis method by simultaneous analysis of , , and X-rays" conducted from FY2020 to FY2022. The present study aims to enable rapid analysis of radionuclides in fuel debris and waste, we have established the latest measurement system, such as the multiple -ray detection methods, and the Spectral Determination Method (hereinafter referred to as "SDM") was developed. In the research in 2022, we developed a code that handles measurement data of LSC, singles Ge, and 2D spectra (multiple ). In addition, to develop an integrated database, spectral data of 40 nuclides were obtained by actual measurements and simulation calculations.

Development of a new corrosion mitigation technology using nanobubbles toward corrosion mitigation in PCV system under the influence of //-rays radiolysis (Contract research); FY2021 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*

JAEA-Review 2022-069, 114 Pages, 2023/03

JAEA-Review-2022-069.pdf:5.91MB

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 FY2021. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station (1F), 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 FY2020, this report summarizes the research results of the "Development of a new corrosion mitigation technology using nanobubbles toward corrosion mitigation in PCV system under the influence of //-rays radiolysis" conducted in FY2021. In this work, in order to ensure the long-term reliability of steel structures that ensure important confinement functions in the debris removal process, such as existing PCVs and newly constructed negative pressure maintenance systems and piping, corrosion phenomena in wet environments where - and -ray emitting nuclides come into contact with steel are clarified for the first time.

Development of a new corrosion mitigation technology using nanobubbles toward corrosion mitigation in PCV system under the influence of //-rays radiolysis (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*

JAEA-Review 2022-002, 85 Pages, 2022/06

JAEA-Review-2022-002.pdf:3.39MB

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 FY2020. 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 FY2020, this report summarizes the research results of the "Development of a new corrosion mitigation technology using nanobubbles toward corrosion mitigation in PCV system under the influence of //-rays radiolysis" conducted in FY2020. In this work, in order to ensure the long-term reliability of steel structures that ensure important confinement functions in the debris removal process, such as existing PCVs and newly constructed negative pressure maintenance systems and piping, corrosion phenomena in wet environments where - and -ray emitting nuclides come into contact with steel are clarified for the first time.

spectrometry of terrestrial gamma rays using portable germanium detectors in area of 80 km radius around the Fukushima Daiichi Nuclear Power Plant

Mikami, Satoshi; Tanaka, Hiroyuki*; Okuda, Naotoshi*; Sakamoto, Ryuichi*; Ochi, Kotaro; Uno, Kiichiro*; Matsuda, Norihiro; Saito, Kimiaki

Nihon Genshiryoku Gakkai Wabun Rombunshi, 20(4), p.159 - 178, 2021/12

https://doi.org/10.3327/taesj.J20.010

In order to know the background radiation level where the area affected by the Fukushima Daiichi Nuclear Power Plant accident in 2011, terrestrial gamma rays had been measured by using portable germanium detectors repeatedly from 2013 through 2019, at 370 locations within 80 km radius area centered on the Fukushima Daiichi Nuclear Power Plant. Radioactive concentrations of Uranium 238, Thorium 232, Potassium 40 and kerma rates in air due to terrestrial gamma rays were obtained at those locations based on the method of ICRU report 53. Averaged concentrations of U, Th and K were 18.8, 22.7, 428 Bq/kg, respectively, and kerma rate in air over the area was found to be 0.0402 Gy/h. The obtained kerma rates in air were compared to those reported in literatures. It was confirmed that the data were correlated with each other, and were agreed within the range of their uncertainty. This is because the kerma rate in air due to terrestrial gamma rays is depend on geology. The similar trend to previous findings was observed that the kerma rate in air at locations geologically classified as Mesozoic era, Granite and Rhyolite were statistically significantly higher than the others.

Measurement of the Se(, n) cross section and uncertainty evaluation of the Se(n, ) cross section

Kitatani, Fumito; Harada, Hideo; Goko, Shinji*; Iwamoto, Nobuyuki; Utsunomiya, Hiroaki*; Akimune, Hidetoshi*; Toyokawa, Hiroyuki*; Yamada, Kawakatsu*; Igashira, Masayuki*

Journal of Nuclear Science and Technology, 53(4), p.475 - 485, 2016/04

https://doi.org/10.1080/00223131.2015.1056760

Recovery of the electrical characteristics of SiC-MOSFETs irradiated with gamma-rays by thermal treatments

Yokoseki, Takashi; Abe, Hiroshi; Makino, Takahiro; Onoda, Shinobu; Tanaka, Yuki*; Kandori, Mikio*; Yoshie, Toru*; Hijikata, Yasuto*; Oshima, Takeshi

Materials Science Forum, 821-823, p.705 - 708, 2015/07

https://doi.org/10.4028/www.scientific.net/MSF.821-823.705

Yields of strand breaks and base lesions induced by soft X-rays in plasmid DNA

Yokoya, Akinari; Fujii, Kentaro; Ushigome, Takeshi; Shikazono, Naoya; Urushibara, Ayumi; Watanabe, Ritsuko

Radiation Protection Dosimetry, 122(1-4), p.86 - 88, 2006/12

https://doi.org/10.1093/rpd/ncl408

We have studied yields of DNA damages induced by soft X-rays obtained from a conventional soft X-ray machine in a LET region between -rays and ultrasoft X-rays. Practically soft X-rays with a broad energy spectrum emitted from a target of heavy metal, such as tungsten, have been widely used not only for radiobiological experiments but also for medical application such as mammography. Radiation weighting factors for these soft X-rays have been assigned to be 1 by ICRP. However, the fraction of a large number of low energy photons in the spectrum (below several tens keV) provided by bremsstrahlung is expected to be more effective for DNA damage induction than -rays since low energy photo- and Auger electrons predominantly ejected in consequence of a photoelectric effect can produce dense clusters of ionization/excitation on DNA molecules. We have examined the yield of DNA strand breaks induced by white soft X-rays (150 kVp, tungsten target). Yields of base lesions revealed by base excision repair enzymes will be also presented.

Time-dependence of differential G-values of OH radicals in water under Ne ion radiolysis

Taguchi, Mitsumasa; Kojima, Takuji

JAEA-Review 2005-001, TIARA Annual Report 2004, p.181 - 182, 2006/01

https://jopss.jaea.go.jp/pdfdata/JAEA-Review-2005-001-p0127-p0267.pdf

The yields of OH radicals in water containing phenol have been investigated for several ten MeV/n C ion and Ne ion having the same LET value, as a function of the residual ion energy at the specific depth in water. In this study, beside such energy dependence, the dependence of reaction time of OH radical yield was examined by changing the concentration of phenol as solute. The defferential G'-values of OH radicals, those G-values per kinetic energy of ions increase with specific energy of Ne ions. The G'-value just after irradiation(1.5ns) is relatively high but become lower with reaction time to be the value (2.7) obtained for Co -rays. It suggests the diffusion behavior of OH radicals locally induced in water.

Estimation methods of blood boron concentration and error evaluation during boron neutron capture therapy for malignant brain tumor

Shibata, Yasushi*; Yamamoto, Kazuyoshi; Matsumura, Akira*; Yamamoto, Tetsuya*; Hori, Naohiko; Kishi, Toshiaki; Kumada, Hiroaki; Akutsu, Hiroyoshi*; Yasuda, Susumu*; Nakai, Kei*; et al.

JAERI-Research 2005-009, 41 Pages, 2005/03

JAERI-Research-2005-009.pdf:1.99MB

The measurement of neutron flux and boron concentration in the blood during medical irradiation is indispensable in order to evaluate the radiation in boron neutron capture therapy. It is, however, difficult to measure the blood boron concentration during neutron irradiation because access to the patient is limited. Therefore we prospectively investigated the predictability of blood boron concentrations using the data obtained at the first craniotomy after infusion of a low dosage of BSH. When the test could not be carried out, the blood boron concentration during irradiation was also predicted by using the 2-compartment model. If the final boron concentration after the end of the infusion is within 95% confidence interval of the prediction, direct prediction from biexponential fit will reduce the error of blood boron concentrations during irradiation to around 6%. If the final boron concentration at 6 or 9 hours after the end of infusion is out of 95% confidence interval of the prediction, proportional adjustment will reduce error and expected error after adjustment to around 12%.