Status report of JAEA-AMS-TONO; Research and technical development in the last four years

Kokubu, Yoko; Fujita, Natsuko; Watanabe, Takahiro; Matsubara, Akihiro; Ishizaka, Chika; Miyake, Masayasu*; Nishio, Tomohiro*; Kato, Motohisa*; Ogawa, Yumi*; Ishii, Masahiro*; et al.

Nuclear Instruments and Methods in Physics Research B, 539, p.68 - 72, 2023/06

https://doi.org/10.1016/j.nimb.2023.03.005

The JAEA-AMS-TONO facility at the Tono Geoscience Center, JAEA has an accelerator mass spectrometer (JAEA-AMS-TONO-5MV). The spectrometer enabled us to use a multi-nuclide AMS of carbon-14 (C), beryllium-10, aluminium-26 and iodine-129, and we have recently been proceeding test measurement of chlorine-36. In response to an increase of samples, we installed a state-of-the-art multi-nuclide AMS with a 300 kV Tandetron accelerator in 2020. Recently, we are driving the development of techniques of isobar separation in AMS and of sample preparation. Ion channeling is applied to remove isobaric interference and we are building a prototype AMS based on this technique for downsizing of AMS. The small sample graphitization for C has been attempted using an automated graphitization equipment equipped with an elemental analyzer.

Present status of the JAEA-AMS-TONO (2022FY)

Fujita, Natsuko; Miyake, Masayasu; Matsubara, Akihiro*; Ishii, Masahiro*; Watanabe, Takahiro; Jinno, Satoshi; Nishio, Tomohiro*; Ogawa, Yumi; Yamamoto, Yusuke; Kimura, Kenji; et al.

Dai-23-Kai AMS Shimpojiumu Hokokushu, p.1 - 4, 2022/12

The JAEA-AMS-TONO facility at the Tono Geoscience Center, JAEA has three accelerator mass spectrometers. We report the present status of the JAEA-AMS-TONO.

Dose estimation for the reuse of wooden chips contaminated by radioactive cesium

Takai, Shizuka; Seki, Masaya; Kimura, Hideo; Takeda, Seiji

Hoken Butsuri, 50(1), p.50 - 66, 2015/03

Wood (thinned wood from forest etc.) and wooden wastes (demolished wood etc.) potentially contaminated by radioactive cesium released by Fukushima Daiichi Nuclear Power Plant have been used for various purposes as wooden chips. However, there has been no dose estimation for use of such contaminated wood so far. Up to now, use of wood has been conducted according to a standard value of 100 Bq/kg for radioactive cesium based on clearance level of concrete and metal generated at nuclear power plant. The purpose of this study is to evaluate the safety of present use of wood by dose estimation for reuse of contaminated wooden chips, which are reused for main five use purposes (particle board, paper, compost, biomass power fuel, mulching). We also calculated activity concentrations of radioactive cesium in wooden chips corresponding to standard dose for safety reuse of radioactive wastes and regarded the minimum calculated activity concentration as a standard value of activity concentration for each reuse purposes. From the result, the minimum standard value of activity concentration of radioactive cesium in wooden chips for all reuse purposes is estimated to be 120 Bq/kg for reuse of wooden chips for particle board. Since this standard value is more than 100 Bq/kg, the safety of present use of wood is confirmed.

Conceptual design of multipurpose compact research reactor; Annual report FY2011

Watahiki, Shunsuke; Hanakawa, Hiroki; Imaizumi, Tomomi; Nagata, Hiroshi; Ide, Hiroshi; Komukai, Bunsaku; Kimura, Nobuaki; Miyauchi, Masaru; Ito, Masayasu; Nishikata, Kaori; et al.

JAEA-Technology 2013-021, 43 Pages, 2013/07

JAEA-Technology-2013-021.pdf:5.12MB

The number of research reactors in the world is decreasing because of their aging. On the other hand, the necessity of research reactor, which is used for human resources development, progress of the science and technology, industrial use and safety research is increasing for the countries which are planning to introduce the nuclear power plants. From above background, the Neutron Irradiation and Testing Reactor Center began to discuss a basic concept of Multipurpose Compact Research Reactor (MCRR) for education and training, etc., on 2010 to 2012. This activity is also expected to contribute to design tool improvement and human resource development in the center. In 2011, design study of reactor core, irradiation facilities with high versatility and practicality, and hot laboratory equipment for the production of Mo-99 was carried out. As the result of design study of reactor core, subcriticality and operation time of the reactor in consideration of an irradiation capsule, and about the transient response of the reactor to the reactivity disturbance during automatic control operation, it was possible to do automatic operation of MCRR, was confirmed. As the result of design study of irradiation facilities, it was confirmed that the implementation of an efficient mass production radioisotope Mo-99 can be expected. As the result of design study with hot laboratory facilities, Mo-99 production, RI export devised considered cell and facilities for exporting the specimens quickly was designed.

Spin chirality and electric polarization in multiferroic compounds RMnO ( = Ho, Er)

Wakimoto, Shuichi; Kimura, Hiroyuki*; Fukunaga, Mamoru*; Nishihata, Keisuke*; Takeda, Masayasu; Kakurai, Kazuhisa; Noda, Yukio*; Tokura, Yoshinori*

Physica B; Condensed Matter, 404(17), p.2513 - 2516, 2009/09

https://doi.org/10.1016/j.physb.2009.06.012

Spiral spin structures and origin of the magnetoelectric coupling in YMnO

Kim, J.-H.*; Lee, S.-H.*; Park, S. I.*; Kenzelmann, M.*; Harris, A. B.*; Schefer, J.*; Chung, J.-H.*; Majkrzak, C. F.*; Takeda, Masayasu; Wakimoto, Shuichi; et al.

Physical Review B, 78(24), p.245115_1 - 245115_10, 2008/12

https://doi.org/10.1103/PhysRevB.78.245115

Engineering design, installation, and conditioning of ferritic steel plates/wall for AMTEX in JFT-2M

Yamamoto, Masahiro*; Shibata, Takatoshi; Tsuzuki, Kazuhiro; Sato, Masayasu; Kimura, Haruyuki; Okano, Fuminori; Kawashima, Hisato; Suzuki, Sadaaki; Shinohara, Koji; JFT-2M Group; et al.

Fusion Science and Technology, 49(2), p.241 - 248, 2006/02

https://doi.org/10.13182/FST06-A1098

JFT-2M has been modified three times in the Advanced Material Tokamak Experiment (AMTEX) program to investigate compatibility of the low activation ferritic steel F82H with tokamak plasmas as a structural material for future reactors. The ferritic steel plate/wall was installed inside and/or outside of the vacuum vessel to reduce the ripple of toroidal magnetic field step by step through three modifications. This paper focuses on engineering aspects in these modifications; electromagnetic analysis to find a suitable way for fixing these plates, installation procedure to keep small tolerance, a three-dimensional magnetic field measurement device used to obtain information of the actual shape of the vacuum vessel used as a installation standard surface. To keep a good surface condition of the ferritic steel plate/wall that rusts easily, careful treatment was executed before the installation. To reduce oxygen impurities further, a boronization system with tri-methyl boron, which is safe and easy to operate, was developed.

Development of lung and soft tissue substitutes for photons

Kinase, Sakae; Kimura, Masaya*; Noguchi, Hiroshi; Yokoyama, Sumi

Radiation Protection Dosimetry, 115(1-4), p.284 - 288, 2005/12

https://doi.org/10.1093/rpd/nci018

We have developed polyurethane-based tissue substitutes simulating lung, soft tissue, muscle, muscle-adipose mixture tissue, cartilage, brain, larynx, trachea, thyroid, kidney, liver and skin. The formulation of the tissue substitutes for photons was based on the basic data method together with an equation for calculating the optimum relative mass of corrective additives. The tissue substitutes were formulated to be phantom materials in the photon energy range of at least 10 keV-10 MeV. In particular, they were designed to match the tissues with linear attenuation coefficients for low photon energy (13.6, 17.2 and 20.2 keV from Pu) and to have the same mass densities as the tissues. The tissue substitutes developed in the present study were examined for the photon transmissions using 16.6 keV KX-rays from Nb. The experimental transmission curves of the substitutes were found to be in good agreement with those derived from data on the tissues in ICRP Publication 23. It was found that the tissue substitutes are suitable as the corresponding tissues defined in ICRP.

High performance tokamak experiments with a ferritic steel wall on JFT-2M

Tsuzuki, Kazuhiro; Kimura, Haruyuki; Kawashima, Hisato; Sato, Masayasu; Kamiya, Kensaku; Shinohara, Koji; Ogawa, Hiroaki; Hoshino, Katsumichi; Bakhtiari, M.; Kasai, Satoshi; et al.

Nuclear Fusion, 43(10), p.1288 - 1293, 2003/10

https://doi.org/10.1088/0029-5515/43/10/033

no abstracts in English

Observation of high recycling steady H-mode edge and compatibility with improved core confinement mode on JFT-2M

Kamiya, Kensaku; Kimura, Haruyuki; Ogawa, Hiroaki; Kawashima, Hisato; Tsuzuki, Kazuhiro; Sato, Masayasu; Miura, Yukitoshi; JFT-2M Group

Nuclear Fusion, 43(10), p.1214 - 1219, 2003/10

https://doi.org/10.1088/0029-5515/43/10/024

no abstracts in English