Orientation mapping of YbSn single crystals based on Bragg-dip analysis using a delay-line superconducting sensor

Shishido, Hiroaki*; Vu, TheDang*; Aizawa, Kazuya; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Oku, Takayuki; Soyama, Kazuhiko; Miyajima, Shigeyuki*; et al.

Journal of Applied Crystallography, 56(4), p.1108 - 1113, 2023/08

https://doi.org/10.1107/S1600576723005204

High spatial resolution neutron transmission imaging using a superconducting two-dimensional detector

Shishido, Hiroaki*; Nishimura, Kazuma*; Vu, TheDang*; Aizawa, Kazuya; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Oku, Takayuki; Soyama, Kazuhiko; et al.

IEEE Transactions on Applied Superconductivity, 31(9), p.2400505_1 - 2400505_5, 2021/12

https://doi.org/10.1109/TASC.2021.3111396

In this study, we employed a superconducting detector, current-biased kinetic-inductance detector (CB-KID) for neutron imaging using a pulsed neutron source. We employed the delay-line method, and high spatial resolution imaging with only four reading channels was achieved. We also performed wavelength-resolved neutron imaging by the time-of-flight method. We obtained the neutron transmission images of a Gd-Al alloy sample, inside which single crystals of GdAl were grown, using the delay-line CB-KID. Single crystals were well imaged, in both shapes and distributions, throughout the Al-Gd alloy. We identified Gd nuclei via neutron transmissions that exhibited characteristic suppression above the neutron wavelength of 0.03 nm. In addition, the Gd resonance dip, a dip structure of the transmission caused by the nuclear reaction between an isotope and neutrons, was observed even when the number of events was summed over a limited area of 15 m 12 m. Gd selective imaging was performed using the resonance dip of Gd, and it showed clear Gd distribution even with a limited neutron wavelength range of 1 pm.

Non-invasive C-imaging revealed the spatiotemporal variability in the translocation of photosynthates into strawberry fruits in response to increasing daylight integrals at leaf surface

Miyoshi, Yuta*; Hidaka, Kota*; Yin, Y.-G.*; Suzui, Nobuo*; Kurita, Keisuke; Kawachi, Naoki*

Frontiers in Plant Science (Internet), 12, p.688887_1 - 688887_14, 2021/07

https://doi.org/10.3389/fpls.2021.688887

In this study, C-photosynthate translocation into strawberry fruits in individual plants was visualized non-invasively and repeatedly using a positron emission tracer imaging system (PETIS) to assess the spatiotemporal variability in the translocation dynamics in response to increasing daylight integrals. This is the first study to use C-radioisotopes to clarify the spatiotemporal variability in photosynthate translocation from source leaves to individual sink fruits in vivo in response to increasing daylight integrals at a high spatiotemporal resolution.

Application of OpenPET as 3-D imaging device of carbon distribution in fruit

Kurita, Keisuke; Miyoshi, Yuta*; Nagao, Yuto*; Yamaguchi, Mitsutaka*; Suzui, Nobuo*; Yin, Y.-G.*; Ishii, Satomi*; Kawachi, Naoki*; Hidaka, Kota*; Yoshida, Eiji*; et al.

QST-M-29; QST Takasaki Annual Report 2019, P. 106, 2021/03

https://repo.qst.go.jp/records/82107

Energy-resolved neutron imaging using a delay line current-biased kinetic-inductance detector

Shishido, Hiroaki*; Nishimura, Kazuma*; Vu, TheDang*; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Miyajima, Shigeyuki*; Hidaka, Mutsuo*; Oku, Takayuki; et al.

Journal of Physics; Conference Series, 1590, p.012033_1 - 012033_8, 2020/10

https://doi.org/10.1088/1742-6596/1590/1/012033

Evaporation of ruthenium from simulated fission-produced alloy precipitates in a nuclear fuel

Liu, J.; Miyahara, Naoya; Miwa, Shuhei; Takano, Masahide; Hidaka, Akihide; Osaka, Masahiko

Journal of Nuclear Materials, 527, p.151819_1 - 151819_7, 2019/12

https://doi.org/10.1016/j.jnucmat.2019.151819

To evaluate the effect of each constituent element on the evaporation rate of ruthenium (Ru) from fission-produced alloy precipitates, the oxidation and evaporation behaviors of metallic Ru, molybdenum (Mo), palladium (Pd), rhodium (Rh) and Mo-Ru-Pd-Rh alloy powders were investigated by thermogravimetric analysis under oxidizing atmospheres from 1473 to 1723 K. The findings led to the following conclusions: (1) The quick oxidation of Mo into condensed Mo oxides can effectively suppress the oxidation and evaporation of Ru in alloy powders; (2) After the complete evaporation of Mo, the evaporation loss rate of Ru would be directly influenced by the Ru activity in the Ru-Pd-Rh alloys, which is determined by the composition of alloys.

Temperature dependent characteristics of neutron signals from a current-biased Nb nanowire detector with B converter

Vu, TheDang; Iizawa, Yuki*; Nishimura, Kazuma*; Shishido, Hiroaki*; Kojima, Kenji*; Oikawa, Kenichi; Harada, Masahide; Miyajima, Shigeyuki*; Hidaka, Mutsuo*; Oku, Takayuki; et al.

Journal of Physics; Conference Series, 1293, p.012051_1 - 012051_9, 2019/10

https://doi.org/10.1088/1742-6596/1293/1/012051

Enhancement of hydrogen generation, radionuclides release at time of resumption of water injection after cooling interruption for several hours during Fukushima Daiichi NPP accident

Hidaka, Akihide; Himi, Masashi*; Addad, Y.*

Proceedings of International Topical Workshop on Fukushima Decommissioning Research (FDR 2019) (Internet), 4 Pages, 2019/05

no abstracts in English

Examination of I and Cs releases during late phase of Fukushima Daiichi NPP accident by using I/Cs ratio of source terms evaluated reversely by WSPEEDI code with environmental monitoring data

Hidaka, Akihide; Yokoyama, Hiroya

Journal of Nuclear Science and Technology, 54(8), p.819 - 829, 2017/08

AA2016-0500.pdf:0.44MB

https://doi.org/10.1080/00223131.2017.1323691

To clarify what happened during the Fukushima accident, the phenomena within RPV and the discussion of ties with the environmental monitoring are very important. However, the previous study has not necessarily advanced until the present that passed almost six years from the accident. The present study investigated I and Cs release behaviors during the late phase of the accident based on I/Cs ratio of the source terms that were recently evaluated backward by WSPEEDI code based on environmental monitoring data. The I release from the contaminated water in the basement of 1F2 and 1F3 reactor buildings was evaluated to be about 10% of I source term. The increase in Cs release from March 21 to 23 and from March 30 to 31 could be explained by the release of CsBO which is formed as a result of chemical reactions of Cs with BC due to re-ascension of the core temperature caused by slight shortage of the core cooling water.

Japan - IAEA Joint Nuclear Energy Management School 2016

Yamaguchi, Mika; Hidaka, Akihide; Ikuta, Yuko; Murakami, Kenta*; Tomita, Akira*; Hirose, Hiroya*; Watanebe, Masanori*; Ueda, Kinichi*; Namaizawa, Ken*; Onose, Takatoshi*; et al.

JAEA-Review 2017-002, 60 Pages, 2017/03

JAEA-Review-2017-002.pdf:9.41MB

Since 2010, IAEA has held the NEM School to develop future leaders who plan and manage nuclear energy utilization in their county. Since 2012, JAEA together with Japan Nuclear HRD Network, University of Tokyo, Japan Atomic Industrial Forum and JAIF International Cooperation Center have cohosted the school in Japan in cooperation with IAEA. Since then, the school has been held in Japan every year. In 2006, Japanese nuclear technology and experience, such as lessons learned from the Fukushima Daiichi Nuclear Power Plant accident, were provided to offer a unique opportunity for the participants to learn about particular cases in Japan. Through the school, we contributed to the internationalization of Japanese young nuclear professionals, development of nuclear human resource of other countries including nuclear newcomers, and enhanced cooperative relationship with IAEA. Additionally, collaborative relationship within the network was strengthened by organizing the school in Japan.