Stable hydrogen and oxygen isotope analyses of geological samples using a thermal conversion elemental analyzer-isotope ratio mass spectrometer at Tono Geoscience Center

Yamamoto, Yusuke*; Watanabe, Takahiro; Niwa, Masakazu; Shimada, Koji

JAEA-Testing 2023-003, 67 Pages, 2024/02

JAEA-Testing-2023-003.pdf:4.63MB

A long-term geosphere stability for geological disposal is evaluated by the past geological environmental changes and modern conditions. Stable hydrogen and oxygen isotope ratios (D, O) of geological samples are useful information to estimate the past environmental changes and modern conditions. Recently, the thermal conversion elemental analyzer and isotope ratio mass spectrometer (TC-EA/IRMS) were installed in the Tono Geoscience Center for D and O measurements of geological samples. In this study, we reported analytical methods of D and O using international standard reference materials. In addition, evaluation tests of uncertainty by repeated analyses of the standards were performed using the TC-EA/IRMS. Furthermore, the D and O analyses by the TC- EA/IRMS were also applied to fault rock samples.

Simple and rapid method for geochemically discriminating of paleotsunami deposits using a portable X-ray fluorescence spectrometry system; Application to boring cores from the Shizuoka plain on the Pacific coast of central Japan

Watanabe, Takahiro; Yamamoto, Yusuke; Kitamura, Akihisa*

Chigaku Zasshi, 132(5), p.417 - 437, 2023/10

https://doi.org/10.5026/jgeography.132.417

To improve a geochemical discrimination method of paleotsunami deposit, quantitative analysis of major and trace elements in boring cores from the Shizuoka plain on the Pacific coast of middle Japan was performed using a portable energy dispersive X-ray fluorescence spectrometry system (portable XRF). Geochemical approaches by the portable XRF contribute to study of the simple and rapid methods for detecting paleotsunami deposits. Most of our quantitative data by portable XRF were good agreement with reported values measured by stationary-type energy dispersive XRF in previous studies. Therefore, the portable XRF can be applied to geochemical study in the samples from Shizuoka plain in our case.

Ion beam induced luminescence analysis of europium complexes in styrene-divinylbenzene copolymer-coated spherical silica by proton and argon ion beams irradiation

Nakahara, Masaumi; Watanabe, So; Takeuchi, Masayuki; Yuyama, Takahiro*; Ishizaka, Tomohisa*; Ishii, Yasuyuki*; Yamagata, Ryohei*; Yamada, Naoto*; Koka, Masashi*; Kada, Wataru*; et al.

Nuclear Instruments and Methods in Physics Research B, 542, p.144 - 150, 2023/09

https://doi.org/10.1016/j.nimb.2023.06.012

The structures of Eu complexes in the adsorbents prepared with various extractants were evaluated by ion beam induced luminescence analysis in an extraction chromatography for minor actinides recovery. The luminescence of Eu was measured with a proton beam obtained from the single-ended accelerator and an argon ion beam obtained from the azimuthally varying field cyclotron in Takasaki Ion Accelerators for Advanced Radiation Application in National Institutes for Quantum Science and Technology. In this study, it was confirmed that the spectral shape of Eu complexes in the adsorbents varied depending on the kinds of extractants, and the correlation between the change in the spectra and the structures of Eu complexes was investigated.

Improvement in the elution performance of an N,N,N',N-tetraoctyl diglycolamide impregnated extraction chromatography adsorbent using neodymium via micro-particle-induced X-ray emission analysis

Takahatake, Yoko; Watanabe, So; Arai, Tsuyoshi*; Sato, Takahiro*; Shibata, Atsuhiro

Applied Radiation and Isotopes, 196, p.110783_1 - 110783_5, 2023/06

https://doi.org/10.1016/j.apradiso.2023.110783

Be analysis of the rock samples from the northeastern shore of Lake Pumoyum Co in south Tibetan Plateau

Nara, Fumiko*; Watanabe, Takahiro; Kokubu, Yoko; Zhu, L.*

Nuclear Instruments and Methods in Physics Research B, 539, p.28 - 32, 2023/06

https://doi.org/10.1016/j.nimb.2023.03.007

Lake Pumoyum Co is located on the south Tibetan Plateau. The lake terraces are developed on the eastern lake shore, and it supposed that the large lake level changes would have happened in Pumoyum Co. The in-situ terrestrial cosmogenic adionuclides can be used to estimate the earth surface processes, such as the erosion rate and exposure age dating of rocks. Here we report the results of Be values of the rock samples from the lake terraces around Pumoyum Co. The concentrations of Be were measured by the JAEA-AMS-TONO-5MV in the Tono Geoscience Center, Japan Atomic Energy Agency. The Be concentrations ranged from 3.78 to 10.810 (atoms/g), but the Be values showed the decreasing trend following to the distance from the lake shore. This result indicates that Be values of the rocks at the shore of Pumoyum Co could be influenced from the erosion rate or tectonic process rather than the exposure date resulting from the lake level changes.

Development of nondestructive elemental analysis system for Hayabusa2 samples using muonic X-rays

Osawa, Takahito; Nagasawa, Shunsaku*; Ninomiya, Kazuhiko*; Takahashi, Tadayuki*; Nakamura, Tomoki*; Wada, Taiga*; Taniguchi, Akihiro*; Umegaki, Izumi*; Kubo, Kenya*; Terada, Kentaro*; et al.

ACS Earth and Space Chemistry (Internet), 7(4), p.699 - 711, 2023/04

https://doi.org/10.1021/acsearthspacechem.2c00303

The concentrations of carbon and other major elements in asteroid samples provide very important information on the birth of life on the Earth and the solar-system evolution. Elemental analysis using muonic X-rays is one of the best analytical methods to determine the elemental composition of solid materials, and notably, is the only method to determine the concentration of light elements in bulk samples in a non-destructive manner. We developed a new analysis system using muonic X-rays to measure the concentrations of carbon and other major elements in precious and expectedly tiny samples recovered from the asteroid Ryugu by spacecraft Hayabusa2. Here we report the development process of the system in 4 stages and their system configurations, The analysis system is composed of a stainless-steel analysis chamber, an acrylic glove box for manipulating asteroid samples in a clean environment, and Ge semiconductor detectors arranged to surround the analysis chamber. The performance of the analysis system, including the background level, which is crucial for the measurement, was greatly improved from the first stage to the later ones. Our feasibility study showed that the latest model of our muonic X-ray analysis system is capable of determining the carbon concentration in Hayabusa2's sample model with an uncertainty of less than 10 percent in a 6-day measurement.

Ion beam induced luminescence spectra of europium complexes in silica-based adsorbent

Nakahara, Masaumi; Watanabe, So; Ishii, Yasuyuki*; Yamagata, Ryohei*; Yamada, Naoto*; Koka, Masashi*; Yuyama, Takahiro*; Ishizaka, Tomohisa*; Kada, Wataru*; Hagura, Naoto*

QST-M-39; QST Takasaki Annual Report 2021, P. 62, 2023/02

https://repo.qst.go.jp/records/86616

In an extraction chromatography method for minor actinides recovery, analysis for the structure of complex in a silica-based adsorbent has been studied to separate minor actinides efficiently. In this study, Eu was used as simulated material of minor actinides, and silica-based adsorbents containing Eu complex were prepared. The ion beam induced luminescence spectra of Eu complexes in silica-based adsorbents were measured, and the basic data for the structures of Eu complexes were obtained.

Development of HCl-free solid phase extraction combined with ICP-MS/MS for rapid assessment of difficult-to-measure radionuclides, 2; Highly sensitive monitoring of Sn in concrete rubble

Do, V. K.; Furuse, Takahiro; Ota, Yuki; Iwahashi, Hiroyuki; Hirosawa, Takashi; Watanabe, Masahisa; Sato, Soichi

Journal of Radioanalytical and Nuclear Chemistry, 331(12), p.5631 - 5640, 2022/12

https://doi.org/10.1007/s10967-022-08612-7

Sn is one of the long-lived fission products that might have been released into the environment after the Fukushima nuclear accident in Japan in 2011. The presence of radionuclides must be monitored for the proper treatment of wastes obtained from decommissioning accident-related nuclear facilities and the surrounding environment. In the work, we propose a reliable method for verifying the presence of Sn in construction materials by combining the HCl-free solid phase extraction on TEVA resin and a selective measurement by inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). The method has been optimized and characterized step by step. More than 95% of chemical recovery was achieved for Sn from typical concrete matrixes. The interference caused by an isobar Te and possible polyatomic interferences from matrixes were effectively suppressed by the developed chemical separation and the tandem MS/MS configuration. The total decontamination factor for the Te interference was of the order of 10. The estimated method detection limit for Sn in concrete as measured at m/z = 160 was 12.1 pg g, which is equivalent to 6.1 mBq g.

Design and actual performance of J-PARC 3 GeV rapid cycling synchrotron for high-intensity operation

Yamamoto, Kazami; Kinsho, Michikazu; Hayashi, Naoki; Saha, P. K.; Tamura, Fumihiko; Yamamoto, Masanobu; Tani, Norio; Takayanagi, Tomohiro; Kamiya, Junichiro; Shobuda, Yoshihiro; et al.

Journal of Nuclear Science and Technology, 59(9), p.1174 - 1205, 2022/09

https://doi.org/10.1080/00223131.2022.2038301

In the Japan Proton Accelerator Research Complex, the purpose of the 3 GeV rapid cycling synchrotron (RCS) is to accelerate a 1 MW, high-intensity proton beam. To achieve beam operation at a repetition rate of 25 Hz at high intensities, the RCS was elaborately designed. After starting the RCS operation, we carefully verified the validity of its design and made certain improvements to establish a reliable operation at higher power as possible. Consequently, we demonstrated beam operation at a high power, namely, 1 MW. We then summarized the design, actual performance, and improvements of the RCS to achieve a 1 MW beam.

Geochemical and grain composition analysis of embankment and debris flow deposits in the Izusan area, Atami City, Shizuoka Prefecture, central Japan

Kitamura, Akihisa*; Okazaki, Sota*; Kondo, Mitsuru*; Watanabe, Takahiro; Nakanishi, Toshimichi*; Hori, Rie*; Ikeda, Masayuki*; Ichimura, Koji; Nakagawa, Yuki; Mori, Hideki*

Shizuoka Daigaku Chikyu Kagaku Kenkyu Hokoku, (49), p.73 - 86, 2022/07

https://doi.org/10.51053/shizuoka.49.0_73

On July 3 2021, a debris flow caused by a landslide from a landfill occurred along the Aizome River in the Izusan area of Atami City, Shizuoka. In this study, debris flow deposits and soil samples were characterized in terms of their sedimentology and geochemically analyzed.