Annual report for FY2021 on the activities of Naraha Center for Remote Control Technology Development (April 1, 2021 - March 31, 2022)

Akiyama, Yoichi; Shibanuma, So; Yanagisawa, Kenichi*; Yamada, Taichi; Suzuki, Kenta; Yoshida, Moeka; Ono, Takahiro; Kawabata, Kuniaki; Watanabe, Kaho; Morimoto, Kyoichi; et al.

JAEA-Review 2023-015, 60 Pages, 2023/09

JAEA-Review-2023-015.pdf:4.78MB

Naraha Center for Remote Control Technology Development (NARREC) was established in Japan Atomic Energy Agency to promote a decommissioning work of Fukushima Daiichi Nuclear Power Station (Fukushima Daiichi NPS). NARREC consists of a Full-scale Mock-up Test Building and Research Management Building. Various test facilities are installed in these buildings for the decommissioning work of Fukushima Daiichi NPS. These test facilities are intended to be used for various users, such as companies engaged in the decommissioning work, research and development institutions, educational institutions and so on. The number of NARREC facility uses was 84 in FY2021. We participated booth exhibitions and presentations on the decommissioning related events. Moreover, we also contributed to the development of human resources by supporting the 6th Creative Robot Contest for Decommissioning. As a new project, "Narahakko Children's Classroom" was implemented for elementary school students in Naraha Town. This report summarizes the activities of NARREC in FY2021, such as the utilization of facilities and equipment of NARREC, the development of remote-control technologies for supporting the decommissioning work, arrangement of the remote-control machines for emergency response, and training for operators by using the machines.

Joint meeting of young researchers in the field of radiation protection and radiation biology

Kataoka, Noriaki*; Nakajima, Junya; Miwa, Kazuji; Hirota, Seiko*; Tsubota, Yoichi; Yamada, Ryohei; Fujimichi, Yuki*; Ishikawa, Junya*; Sunaoshi, Masaaki*

Hoken Butsuri (Internet), 54(2), p.140 - 145, 2019/06

https://doi.org/10.5453/jhps.54.140

It is the written report of the joint meeting of young researchers in the field of radiation protection and radiation biology.

Rapid separation of zirconium using microvolume anion-exchange cartridge for Zr determination with isotope dilution ICP-MS

Asai, Shiho; Hanzawa, Yukiko; Konda, Miki; Suzuki, Daisuke; Magara, Masaaki; Kimura, Takaumi; Ishihara, Ryo*; Saito, Kyoichi*; Yamada, Shinsuke*; Hirota, Hideyuki*

Talanta, 185, p.98 - 105, 2018/08

https://doi.org/10.1016/j.talanta.2018.03.026

Estimating the risks associated with radiation from long-lived fission products (LLFP) in radioactive waste is essential to ensure the long-term safety of potential disposal sites. In this study, the amount of Zr, a LLFP, was determined by ICP-MS after separating Zr from a spent nuclear fuel solution using a microvolume anion-exchange cartridge (TEDA cartridge). The TEDA cartridge achieved highly selective separation of Zr regardless of its small bed volume of 0.08 cm. The time taken to complete the Zr separation was 1.2 min with a flow rate of 1.5 mL/min, which was 10 times faster than that for a conventional anion-exchange resin column. Almost all the other elements were removed, leading to accurate measurement of Zr. The result connects experimental value to theoretical prediction provided by ORIGEN2, which requires verification. With the measured value, we demonstrated that the theoretical value is reliable enough to estimate radiation risks.

Electronic states of highly ordered DNTT and picene molecular layer

Hasegawa, Yuri; Yamada, Yoichi*; Sasaki, Masahiro*

Vacuum and Surface Science, 61(6), p.366 - 371, 2018/06

https://doi.org/10.1380/vss.61.366

Molecular arrangements and electronic states of well-ordered (DNTT) and picene thin film on single crystal were measured by means of scanning tunneling microscope (STM) and angle-resolved photoemission spectroscopy, respectively. DNTT and picene form single crystalline-like molecular arrangement on inert Au(111) substrate. Splitting of HOMO energy due to overlapping with adjacent molecules was suggested by ultraviolet photoemission spectroscopy (UPS) and density functional theory (DFT) calculation. On the other hand, one-dimensional ordering of those molecule was observed on anisotropic Ag(110) substrate. However, the HOMO band dispersion was found to be 200 meV at maximum, showing that the overlapping of HOMO was smaller in such arrangement comparing with that in their single crystal.

Inelastic and quasi-elastic neutron scattering spectrometers in J-PARC

Seto, Hideki; Ito, Shinichi; Yokoo, Tetsuya*; Endo, Hitoshi*; Nakajima, Kenji; Shibata, Kaoru; Kajimoto, Ryoichi; Kawamura, Seiko; Nakamura, Mitsutaka; Kawakita, Yukinobu; et al.

Biochimica et Biophysica Acta; General Subjects, 1861(1), p.3651 - 3660, 2017/01

https://doi.org/10.1016/j.bbagen.2016.04.025

J-PARC, Japan Proton Accelerator Research Complex provides short pulse proton beam at a repetition rate 25 Hz and the maximum power is expected to be 1 MW. Materials and Life Science Experimental Facility (MLF) has 23 neutron beam ports and 21 instruments have already been operated or under construction / commissioning. There are 6 inelastic / quasi-elastic neutron scattering spectrometers and the complementary use of these spectrometers will open new insight for life science.

Detection of molecular oxygen adsorbate during room-temperature oxidation of Si(100)21 surface; In situ synchrotron radiation photoemission study

Yoshigoe, Akitaka; Yamada, Yoichi*; Taga, Ryo*; Ogawa, Shuichi*; Takakuwa, Yuji*

Japanese Journal of Applied Physics, 55(10), p.100307_1 - 100307_4, 2016/09

https://doi.org/10.7567/JJAP.55.100307

Synchrotron radiation photoelectron spectroscopy during the oxidation of the Si(100)21 surface at room temperature revealed the existence of the molecularly adsorbed oxygen, which was considered to be absent. The O 1s spectra was found to be similar to that of the oxidation of Si(111)77 surfaces. Also the molecular oxygen was appeared after the initial surface oxides, indicating that this was not a precursor for dissociation oxygen adsorption onto the clean surface. We have proposed presumable structural models for atomic configurations, where the molecular oxygen was resided on the oxidized silicon with two oxygen atoms at the backbonds.

Neutron scattering study of spin fluctuations in LaSrCuO by four-dimensional mapping of neutron cross-sections using the 4SEASONS chopper spectrometer

Wakimoto, Shuichi; Ikeuchi, Kazuhiko*; Arai, Masatoshi; Fujita, Masaki*; Kajimoto, Ryoichi; Kawamura, Sho*; Matsuura, Masato*; Nakajima, Kenji; Yamada, Kazuyoshi*

JPS Conference Proceedings (Internet), 8, p.034013_1 - 034013_6, 2015/09

https://doi.org/10.7566/JPSCP.8.034013

In situ synchrotron radiation photoemission study of ultrathin surface oxides of Ge(111)-c(28) induced by supersonic O beams

Okada, Ryuta; Yoshigoe, Akitaka; Teraoka, Yuden; Yamada, Yoichi*; Sasaki, Masahiro*

Applied Physics Express, 8(2), p.025701_1 - 025701_4, 2015/02

https://doi.org/10.7567/APEX.8.025701

We studied the surface oxidation on a Ge(111)-c(28) surface at room temperature using supersonic oxygen beams as a function of the translational energy of the incident oxygen molecules ranging from 26 meV to 2.3 eV. In situ synchrotron photoemission spectroscopy performed during the oxidation revealed that the surface oxidation terminated with the formation of a sub-monolayer oxide of at most 0.52 ML, for all the beam energies examined. In addition, the oxidation state of the surface oxides was found to depend on the translational energy. These results demonstrate the precise chemical control of the ultrathin surface oxides of Ge(111)-c(28).

Radiation monitoring using manned helicopter around the Fukushima Daiichi Nuclear Power Station in the fiscal year 2013 (Contract research)

Sanada, Yukihisa; Nishizawa, Yukiyasu; Urabe, Yoshimi; Yamada, Tsutomu; Ishida, Mutsushi; Sato, Yoshiharu; Hirayama, Hirokatsu; Takamura, Yoshihide; Nishihara, Katsuya; Imura, Mitsuo; et al.

JAEA-Research 2014-012, 110 Pages, 2014/08

JAEA-Research-2014-012.pdf:169.17MB
JAEA-Research-2014-012(errata).pdf:0.27MB

By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (NPS), Tokyo Electric Power Company (TEPCO), caused by the East Japan earthquake and the following tsunami occurred on March 11, 2011, a large amount of radioactive materials was released from the NPP. This document was summarized in the results of the aerial radiation monitoring using the manned helicopter in the fiscal 2013.

Magnetic and electronic properties of (LaMnO)(SrMnO) superlattice revealed by resonant soft X-ray scattering

Kubota, Masato; Yamada, Hiroyuki*; Nakao, Hironori*; Okamoto, Jun*; Yamasaki, Yuichi*; Sawa, Akihito*; Murakami, Yoichi*

Japanese Journal of Applied Physics, 53(5S1), p.05FH07_1 - 05FH07_5, 2014/05

https://doi.org/10.7567/JJAP.53.05FH07