None

Matsubara, Ryuta*; Ueno, Fuga*; Iwata, Hajime; Inagaki, Yaohiro*; Okubo, Takahiro*

NUMO-TR-24-03, p.55 - 61, 2024/10

https://www.numo.or.jp/technology/technical_report/pdf/NUMO-TR-24-03.pdf

no abstracts in English

"Invisible" radioactive cesium atoms revealed; Pollucite inclusion in cesium-rich microparticles (CsMPs) from the Fukushima Daiichi Nuclear Power Plant

Miyazaki, Kanako*; Takehara, Masato*; Minomo, Kenta*; Horie, Kenji*; Takehara, Mami*; Yamasaki, Shinya*; Saito, Takumi*; Onuki, Toshihiko*; Takano, Masahide; Shiotsu, Hiroyuki; et al.

Journal of Hazardous Materials, 470(15), p.134104_1 - 134104_11, 2024/05

https://doi.org/10.1016/j.jhazmat.2024.134104

Thermally altered subsurface material of asteroid (162173) Ryugu

Kitazato, Kohei*; Milliken, R. E.*; Iwata, Takahiro*; Abe, Masanao*; Otake, Makiko*; Matsuura, Shuji*; Takagi, Yasuhiko*; Nakamura, Tomoki*; Hiroi, Takahiro*; Matsuoka, Moe*; et al.

Nature Astronomy (Internet), 5(3), p.246 - 250, 2021/03

https://doi.org/10.1038/s41550-020-01271-2

Here we report observations of Ryugu's subsurface material by the Near-Infrared Spectrometer (NIRS3) on the Hayabusa2 spacecraft. Reflectance spectra of excavated material exhibit a hydroxyl (OH) absorption feature that is slightly stronger and peak-shifted compared with that observed for the surface, indicating that space weathering and/or radiative heating have caused subtle spectral changes in the uppermost surface. However, the strength and shape of the OH feature still suggests that the subsurface material experienced heating above 300 C, similar to the surface. In contrast, thermophysical modeling indicates that radiative heating does not increase the temperature above 200 C at the estimated excavation depth of 1 m, even if the semimajor axis is reduced to 0.344 au. This supports the hypothesis that primary thermal alteration occurred due to radiogenic and/or impact heating on Ryugu's parent body.

Radioactive Cs in the severely contaminated soils near the Fukushima Daiichi Nuclear Power Plant

Kaneko, Makoto*; Iwata, Hajime; Shiotsu, Hiroyuki; Masaki, Shota*; Kawamoto, Yuji*; Yamasaki, Shinya*; Nakamatsu, Yuki*; Imoto, Jumpei*; Furuki, Genki*; Ochiai, Asumi*; et al.

Frontiers in Energy Research (Internet), 3, p.37_1 - 37_10, 2015/09

https://doi.org/10.3389/fenrg.2015.00037

The mobility of the aggregates of submicron-sized sheet aluminosilicate in the surface environment is a key factor controlling the current Cs migration in Fukushima.

Beam-palarization asymmetries for the (,) and (,) reactions for =1.5-2.4 GeV

Zegers, R. G. T.*; Sumihama, Mizuki*; Ahn, D. S.*; Ahn, J. K.*; Akimune, Hidetoshi*; Asano, Yoshihiro; Chang, W. C.*; Dat, S.*; Ejiri, Hiroyasu*; Fujimura, Hisako*; et al.

Physical Review Letters, 91(9), p.092001_1 - 092001_4, 2003/08

https://doi.org/10.1103/PhysRevLett.91.092001

no abstracts in English

Development of "Data-Free-Way" Distributed Database System for Advanced Nuclear Materials

Ueno, Fumiyoshi; Kano, Shigeki; Fujita, Mitsutane*; Kurihara, Yutaka*; Nakajima, Hajime*; Yokoyama, Norio*; Iwata, Shuichi*

Journal of Nuclear Science and Technology, 31(12), p.1314 - 1324, 1994/00

https://doi.org/10.1080/18811248.1994.9735295

None

On Data-free-way; Distributed material database for nuclear applications

Fujita, Mitsutane*; Nakajima, Hajime; Ueno, Fumiyoshi*; Iwata, Shuichi*

Genshiryoku Kogyo, 39(10), p.53 - 57, 1993/00

http://ci.nii.ac.jp/naid/40001074212

no abstracts in English

System design of pilot data-free-way; Distributed database for advanced nuclear materials

Nakajima, Hajime; ; ; Ueno, Fumiyoshi*; Fujita, Mitsutane*; ; Iwata, Shuichi*

Journal of Nuclear Materials, 191-194, p.1046 - 1050, 1992/00

https://doi.org/10.1016/0022-3115(92)90634-W

no abstracts in English

Objective and conceptual design of data-free-way system; Distributed data base for advanced nuclear materials

Fujita, Mitsutane*; Nakajima, Hajime; ; Iwata, Shuichi*

Computer Aided Innovation of New Materials, p.25 - 28, 1991/00

no abstracts in English

R&D program of operational model of long-term performance for vitrified high-level radioactive waste

Matsubara, Ryuta*; Fujisaki, Kiyoshi*; Ishida, Keisuke*; Ishiguro, Katsuhiko*; Inagaki, Yaohiro*; Okubo, Takahiro*; Mitsui, Seiichiro; Iwata, Hajime; Sekine, Nobuyuki*

no journal, , 

Since the performance of vitrified High-level Radioactive Waste depends on thermal, hydraulic, mechanical, and chemical (THMC) conditions, NUMO, as the implementer of geological disposal, has been promoting R&D of operational model the long-term performance of vitrified High-level Radioactive Waste in consideration of THMC conditions. NUMO has identified R&D issues regarding the glass dissolution and planed the R&D program through FEP (Features, Events, and Processes) analysis and parametric study with numerical model to evaluate relative importance of relevant processes. At present, three R&D programs are ongoing as joint researches with JAEA and two universities: long term glass dissolution experiment to understand evolution of glass dissolution kinetics, glass dissolution experiment at various environmental conditions to assess the performance under several potential repository conditions with the time evolution, and molecular dynamics simulation to understand elemental migration at the interface between glass surface and groundwater. The current status of R&D programs will be introduced in this presentation.