Determination of Cs/Cs isotopic ratio in soil collected near Fukushima Daiichi Nuclear Power Station through mass spectrometry

Shimada, Asako; Tsukahara, Takehiko*; Nomura, Masao*; Kim, M. S.*; Shimada, Taro; Takeda, Seiji; Yamaguchi, Tetsuji

Journal of Nuclear Science and Technology, 58(11), p.1184 - 1194, 2021/11

https://doi.org/10.1080/00223131.2021.1931520

Determining the completeness of nuclear reactor decommissioning is an important step in safely utilizing nuclear power. For example, Cs from the Fukushima Daiichi Nuclear Power Station (FDNPS) accident can be treated as background radioactivity, so determining the origin of Cs is essential. To accomplish this, measuring the Cs/Cs isotope ratio can be useful, so this study optimized a solvent extraction method, with calix[4]arene-bis(t-octylbenzo-crown-6) [BOBCalixC6] in 1-octanol, to purify radioactive Cs, radiocesium, from a solution of major environmental soil elements and mass spectrometry interference elements. This optimized method was applied to Cs purification in soil samples (40 g), and the final solutions contained a total of 10g/ml of the major soil elements and ng/ml concentrations at most of interfering elements. Soil samples collected near the FDNPS were then purified, and the Cs/Cs isotope ratios were measured, using both thermal ionization mass spectrometry (TIMS) and triple quadrupole induced coupled plasma mass spectrometry (ICP-QQQ). The results of each of these measurements were compared, and we found that Cs isotope ratios obtained by TIMS were more precise, by an order of magnitude, while the ICP-QQQ results possessed good abundance sensitivities. A slightly higher Cs/Cs ratio in the northwest area of the FDNPS was observed, while other areas exhibited similar values, all within the measurement error range, which indicated different origins of radiocesium. These results agreed with previously reported Cs/Cs activity distributions, suggesting that this ratio may be useful in identifying radiocesium origins for evaluating future nuclear reactor decommissions.

High-pressure study of ScH; Raman, infrared, and visible absorption spectroscopy

Kume, Tetsuji*; Oura, Hiroyuki*; Takeichi, Tomoo*; Omura, Ayako*; Machida, Akihiko; Watanuki, Tetsu; Aoki, Katsutoshi; Sasaki, Shigeo*; Shimizu, Hiroyasu*; Takemura, Kenichi*

Physical Review B, 84(6), p.064132_1 - 064132_7, 2011/08

https://doi.org/10.1103/PhysRevB.84.064132

Raman, IR, and visible absorption spectra of scandium trihydride (ScH) have been measured at high pressures up to 50 GPa at room temperature. The structural and electronic phase transitions were investigated. Successive hcp-intermediate-fcc phase transitions took place at 25 and 46 GPa. It was suggested that the intermediate phase of ScH has the same structure as that of YH. The energy gap of ScH is 1.7 eV at the ambient condition and is closed around 50 GPa, at which the crystal structure transforms to fcc.

Large-scale identification and characterization of alternative splicing variants of human gene transcripts using 56 419 completely sequenced and manually annotated full-length cDNAs

Takeda, Junichi*; Suzuki, Yutaka*; Nakao, Mitsuteru*; Barrero, R. A.*; Koyanagi, Kanako*; Jin, L.*; Motono, Chie*; Hata, Hiroko*; Isogai, Takao*; Nagai, Keiichi*; et al.

Nucleic Acids Research, 34(14), p.3917 - 3928, 2006/00

https://doi.org/10.1093/nar/gkl507

We report the first genome-wide identification and characterization of alternative splicing in human gene transcripts based on analysis of the full-length cDNAs. Applying both manual and computational analyses for 56 419 completely sequenced and precisely annotated full-length cDNAs selected for the H-Invitational human transcriptome annotation meetings, we identified 6877 alternative splicing genes with 18 297 different alternative splicing variants. A total of 37 670 exons were involved in these alternative splicing events. The encoded protein sequences were affected in 6005 of the 6877 genes. Notably, alternative splicing affected protein motifs in 3015 genes, subcellular localizations in 2982 genes and transmembrane domains in 1348 genes. Genome-wide annotations of alternative splicing, relying on full-length cDNAs, should lay firm groundwork for exploring in detail the diversification of protein function which is mediated by the alternative splicing variants.

Crack propagation tests of HIPed DSCu/SS joints for plasma facing components

Hatano, Toshihisa; Goto, Masahiro*; Yamada, Tetsuji*; Nomura, Yuichiro*; Saito, Masakatsu*

Fusion Engineering and Design, 49-50, p.207 - 212, 2000/11

https://doi.org/10.1016/S0920-3796(00)00443-9

no abstracts in English

Overview of STRAD project for systematic treatments of radioactive liquid wastes generated in nuclear facilities

Watanabe, So; Ogi, Hiromichi*; Arai, Yoichi; Aihara, Haruka; Shibata, Atsuhiro; Nomura, Kazunori; Kamiya, Yuichi*; Asanuma, Noriko*; Matsuura, Haruaki*; Kubota, Toshio*; et al.

no journal, ,