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.

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.

PSTEP: Project for solar-terrestrial environment prediction

Kusano, Kanya*; Ichimoto, Kiyoshi*; Ishii, Mamoru*; Miyoshi, Yoshizumi*; Yoden, Shigeo*; Akiyoshi, Hideharu*; Asai, Ayumi*; Ebihara, Yusuke*; Fujiwara, Hitoshi*; Goto, Tadanori*; et al.

Earth, Planets and Space (Internet), 73(1), p.159_1 - 159_29, 2021/12

https://doi.org/10.1186/s40623-021-01486-1

The PSTEP is a nationwide research collaboration in Japan and was conducted from April 2015 to March 2020, supported by a Grant-in-Aid for Scientific Research on Innovative Areas from the Ministry of Education, Culture, Sports, Science and Technology of Japan. It has made a significant progress in space weather research and operational forecasts, publishing over 500 refereed journal papers and organizing four international symposiums, various workshops and seminars, and summer school for graduate students at Rikubetsu in 2017. This paper is a summary report of the PSTEP and describes the major research achievements it produced.

Structural characterization of Eu-HONTA complexes by IBIL and EXAFS analyses

Watanabe, So; Sano, Yuichi; Okada, Makoto*; Matsuura, Haruaki*; Hagura, Naoto*; Kada, Wataru*

Nuclear Instruments and Methods in Physics Research B, 477, p.60 - 65, 2020/08

https://doi.org/10.1016/j.nimb.2019.10.004

IBIL and EXAFS analyses were applied on strucutral analysis of Eu complex formed in adsorbent developed for extraction chromatography. Those analyses revealed slight structural difference between adsorbent and solvent systems.

First nuclear transmutation of Np and Am by accelerator-driven system at Kyoto University Critical Assembly

Pyeon, C. H.*; Yamanaka, Masao*; Oizumi, Akito; Fukushima, Masahiro; Chiba, Go*; Watanabe, Kenichi*; Endo, Tomohiro*; Van Rooijen, W. G.*; Hashimoto, Kengo*; Sakon, Atsushi*; et al.

Journal of Nuclear Science and Technology, 56(8), p.684 - 689, 2019/08

https://doi.org/10.1080/00223131.2019.1618406

This study demonstrates, for the first time, the principle of nuclear transmutation of minor actinide (MA) by the accelerator-driven system (ADS) through the injection of high-energy neutrons into the subcritical core at the Kyoto University Critical Assembly. The main objective of the experiments is to confirm fission reactions of neptunium-237 (Np) and americium-241 (Am), and capture reactions of Np. Subcritical irradiation of Np and Am foils is conducted in a hard spectrum core with the use of the back-to-back fission chamber that obtains simultaneously two signals from specially installed test (Np or Am) and reference (uranium-235) foils. The first nuclear transmutation of Np and Am by ADS soundly implemented by combining the subcritical core and the 100 MeV proton accelerator, and the use of a lead-bismuth target, is conclusively demonstrated through the experimental results of fission and capture reaction events.

Analysis on adsorbent for spent solvent treatment by micro-PIXE and EXAFS

Arai, Yoichi; Watanabe, So; Ono, Shimpei; Nakamura, Masahiro; Shibata, Atsuhiro; Nakamura, Fumiya*; Arai, Tsuyoshi*; Seko, Noriaki*; Hoshina, Hiroyuki*; Hagura, Naoto*; et al.

International Journal of PIXE, 29(1&2), p.17 - 31, 2019/00

https://doi.org/10.1142/S0129083519500128

The spent PUREX solvent containing U and Pu is generated from the reprocessing process of spent nuclear fuel. The nuclear material removal is important for the safe storage or disposal of the spent solvent. Our previous study revealed that the adsorbent with the iminodiacetic acid (IDA) functional group is one of the most promising materials for designing the nuclear material recovery process. Accordingly, an IDA-type adsorbent was synthesized by using graft polymerization technology or a chemical reaction to improve the adsorption rate and capacity. The synthesized IDA-type adsorbent was characterized by micro particle-induced X-ray emission (PIXE) and extended X-ray absorption fine structure (EXAFS) analyses. The micro-PIXE analysis revealed that Zr was adsorbed on the whole synthesized adsorbents and quantified the microamount of adsorbed Zr. Moreover, EXAFS suggested that Zr in the aqueous solution and solvent can be trapped by the IDA group with different mechanisms.

decay of semi-magic Cd; Revision and extension of the level scheme of In

Jungclaus, A.*; Grawe, H.*; Nishimura, Shunji*; Doornenbal, P.*; Lorusso, G.*; Simpson, G. S.*; Sderstrm, P. A.*; Sumikama, Toshiyuki*; Taprogge, J.*; Xu, Z. Y.*; et al.

Physical Review C, 94(2), p.024303_1 - 024303_8, 2016/08

https://doi.org/10.1103/PhysRevC.94.024303

decay of Cd and excited states in In

Taprogge, J.*; Jungclaus, A.*; Grawe, H.*; Nishimura, Shunji*; Doornenbal, P.*; Lorusso, G.*; Simpson, G. S.*; Sderstrm, P.-A.*; Sumikama, Toshiyuki*; Xu, Z. Y.*; et al.

Physical Review C, 91(5), p.054324_1 - 054324_11, 2015/05

https://doi.org/10.1103/PhysRevC.91.054324

Identification of a millisecond isomeric state in Cd via the detection of internal conversion and Compton electrons

Taprogge, J.*; Jungclaus, A.*; Grawe, H.*; Nishimura, Shunji*; Xu, Z. Y.*; Doornenbal, P.*; Lorusso, G.*; Ncher, E.*; Simpson, G. S.*; Sderstrm, P.-A.*; et al.

Physics Letters B, 738, p.223 - 227, 2014/11

https://doi.org/10.1016/j.physletb.2014.09.047

Monopole-driven shell evolution below the doubly magic nucleus Sn explored with the long-lived isomer in Pd

Watanabe, H.*; Lorusso, G.*; Nishimura, Shunji*; Otsuka, T.*; Ogawa, K.*; Xu, Z. Y.*; Sumikama, Toshiyuki*; Sderstrm, P.-A.*; Doornenbal, P.*; Li, Z.*; et al.

Physical Review Letters, 113(4), p.042502_1 - 042502_6, 2014/07

https://doi.org/10.1103/PhysRevLett.113.042502