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Toyoda, Shin*; Inoue, Kazuhiko*; Yamaguchi, Ichiro*; Hoshi, Masaharu*; Hirota, Seiko*; Oka, Toshitaka; Shimazaki, Tatsuya*; Mizuno, Hideyuki*; Tani, Atsushi*; Yasuda, Hiroshi*; et al.
Radiation Protection Dosimetry, 199(14), p.1557 - 1564, 2023/09
Times Cited Count：0 Percentile：0.01(Environmental Sciences)Interlaboratory comparison studies are important for radiation dosimetry in order to demonstrate how the technique is universally available. The set of standard samples are examined in each participating laboratory in the present study. After a set of standard samples together with the samples with unknown doses, which were prepared in the same laboratory as the standard samples, are measured at a participating laboratory, those samples are sent to another participating laboratory for next measurement. There is some small difference observed in the sensitivity (the slope of the dose response line) of the standard samples while the differences in the obtained doses for the samples with unknown doses are rather systematic, implying that the difference is mostly due to the samples but not to measurements.
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
Times Cited Count：43 Percentile：96.93(Astronomy & Astrophysics)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.
Sasaki, Takayuki*; Kokami, Takayuki*; Kobayashi, Taishi*; Kirishima, Akira*; Murakami, Hiroaki; Amano, Yuki; Mizuno, Takashi; Iwatsuki, Teruki; Sasamoto, Hiroshi; Miyakawa, Kazuya
Journal of Nuclear Science and Technology, 54(3), p.373 - 381, 2017/03
Trace amounts of natural thorium and uranium in deep groundwater were investigated at two underground research laboratories situated at Horonobe and Mizunami, Japan. The groundwater was sampled from underground boreholes, and the colloid contribution was checked by in situ two size-fractionated ultrafiltration systems. A decrease in the concentration after in situ filtration suggested the presence of natural colloids and suspended matter that were carriers of a portion of the elements. The result of the Th and U concentrations in groundwater after 10 kDa filtration was analyzed thermodynamically using existing hydrogeological and geochemical data such as the mineral components in the groundwater at a given pH, ionic strength, concentration of co-existing ions, redox potential, and solid phase assumed. A crystalline solid phase made the solubility very low compared with that of the amorphous phase, and the solubility agreed well with the concentrations measured.
Murakami, Takuma; Sasamoto, Hiroshi; Mizuno, Takashi
Chikyu Kagaku, 50(4), p.299 - 317, 2016/12
Development of techniques for investigating the long-term migration of elements in deep underground is important with respect to safety assessment for the geological disposal of high-level radioactive waste. As one study of the migration of elements in deep underground, the distribution of REE, Th and U in sedimentary rock of Horonobe area in Hokkaido was investigated, and discussed whether the difference of hydrogeological structure and lithofacies influences on the distributions. As the results, it was considered that REE and Th were mainly retained in minerals originating from terrigenous clastic and secondary mineral occurred in early diagenesis, and their distributions were relatively homogenous in both the Koetoi and Wakkanai formations. Uranium was indicated to be maintained in the sedimentary rock until now after depositing in deep-sea sediment. It was considered that the U deposition was occurred by adsorption on organic matter and reductive precipitation with decomposition of organic matter. In addition, it was confirmed that the distributions of these elements were not influenced by the difference of hydrogeological and lithofacies.
Hama, Katsuhiro; Mizuno, Takashi; Sasao, Eiji; Iwatsuki, Teruki; Saegusa, Hiromitsu; Sato, Toshinori; Fujita, Tomoo; Sasamoto, Hiroshi; Matsuoka, Toshiyuki; Yokota, Hideharu; et al.
JAEA-Research 2015-007, 269 Pages, 2015/08
JAEA-Research-2015-007.pdf:68.65MBJAEA-Research-2015-007(errata).pdf:0.07MB
We have synthesised the research results from Mizunami/Horonobe URLs and geo-stability projects in the second mid-term research phase. It could be used as technical bases for NUMO/Regulator in each decision point from sitting to beginning of disposal (Principal Investigation to Detailed Investigation Phase). High quality construction techniques and field investigation methods have been developed and implemented and these will be directly applicable to the National Disposal Program (along with general assessments of hazardous natural events and processes). It will be crucial to acquire technical knowledge on decisions of partial backfilling and final closure by actual field experiments in Mizunami/Horonobe URLs as main themes for the next phases.
Sasamoto, Hiroshi; Yamamoto, Nobuyuki; Miyakawa, Kazuya; Mizuno, Takashi
JAEA-Data/Code 2014-033, 43 Pages, 2015/03
JAEA-Data-Code-2014-033.pdf:3.92MB
JAEA-Data-Code-2014-033-appendix(CD-ROM).zip:0.09MB
Development of technologies to investigate properties (conditions) of deep geological environment and models development of geological environment have been pursued in "Geoscientific Research" in the Horonobe underground research laboratory (Horonobe URL) project. A geochemical model of groundwater evolution which is a part of geological environment model requires the data of groundwater chemistry around the Horonobe URL for the development. This report summarizes the data obtained for 3 years (i.e., from the fiscal year 2011 to 2013), especially for the results for measurement of physico-chemical parameters and analysis of groundwater chemistry, in the Horonobe URL project.
Matsui, Hiroya; Mizuno, Takashi; Sasamoto, Hiroshi; Sato, Toshinori
Dai-13-Kai Iwa No Rikigaku Kokunai Shimpojiumu Koen Rombunshu (CD-ROM), p.365 - 370, 2013/01
Japan Atomic Energy Agency has been conducted a contract study with METI (Ministry of Economy, Trade and Industry) called "The project for Grouting Technology Development" since 2008. As a part of the study, the monitoring of groundwater chemistry in a pre-grouted area has been carried out for four years after pre-grouting in Mizunami URL. Measured groundwater pressures were temporarily changed by the earthquakes with more than three of seismic intensity and it was recovered within about one year. Meanwhile, the change of the chemical compositions in groundwater by the earthquakes were not detected and it show a injected grout material was not damaged significantly.
Shimo, Michito*; Kumamoto, So*; Kosaka, Hiroshi; Onoe, Hironori; Saegusa, Hiromitsu; Mizuno, Takashi; Oyama, Takuya
JAEA-Research 2012-004, 126 Pages, 2012/04
JAEA-Research-2012-004.pdf:14.3MB
One of the goals of Mizunami Underground Research Laboratory (MIU) Project is to develop technical basis for investigation, analysis and evaluation technologies for understanding deep underground geological environment in various scales. Understanding groundwater flow system is one of the important issues in the project, and to achieve this purpose, technologies for a hydrogeological model and the groundwater flow simulation technique, have to be established. In this study, hydrogeological modeling and groundwater flow simulations have been carried out in order to predict hydraulic and geochemical impacts around the MIU Construction Site and inflow rate into the MIU facilities. As a result of this study, the significant hydrogeological structures could be estimated. The inflow rate into the MIU facilities and hydraulic and geochemical impacts with the MIU facilities construction could be predicted. The effect of pre-grouting to the MIU facilities could be also confirmed.
Matsui, Hiroya; Mizuno, Takashi; Sasamoto, Hiroshi; Sugihara, Kozo; Yui, Mikazu
Dai-41-Kai Gamban Rikigaku Ni Kansuru Shimpojiumu Koenshu (CD-ROM), p.179 - 184, 2012/01
Japan Atomic Energy Agency has been conducted a contract study with METI (Ministry of Economy, Trade and Industry) called "The project for Grouting Technology Development" since 2008. As a part of the study, the monitoring of groundwater chemistry in a pre-grouted area has been carried out for three and half years after pre-grouting in Mizunami URL. The results suggested that the chemical compositions in groundwater affected by pre-grouting was recovered and the period to recover is evaluated about two years around an underground opening.
Mizuno, Takashi; Nagata, Hiroshi; Iwatsuki, Teruki; Honda, Teruyuki*
Tokyo Toshi Daigaku Genshiryoku Kenkyusho Kenkyushoho, (36), p.14 - 24, 2010/07
This paper aims to understanding the behavior of the elements related to the change of the chemical properties of sedimentary rocks and granitic rocks distributed in the Tono area, Gifu prefecture, using natural analogue approach. As a result, in the sedimentary rocks, it is indicated that REE and U are migrated in response to the change of pH and/or redox condition. These elements will be dissolved from the rocks and introduced into clayminerals, carbonate minerals and phosphate minerals. On the other hand, ingranitic rocks, these elements do not show the systematical variation. It is needed to more detail analysis (ex. chemical analysis of each separated minerals) for understanding their behavior in the granitic rocks.
Shen, G.; Watanabe, Kazuhiko*; Kato, Yuko; Sakaki, Hironao; Sako, Hiroyuki; Ito, Yuichi; Yoshikawa, Hiroshi; Hanawa, Katsushi*; Mizuno, Seiji*
Proceedings of 3rd Annual Meeting of Particle Accelerator Society of Japan and 31st Linear Accelerator Meeting in Japan (CD-ROM), p.364 - 366, 2006/00
The control system of J-PARC project is under construction. After almost finishing the hardware installation of the L3BT section, an online device commissioning was performed for magnet power supply, stepping motor and vacuum system. Many components for device control have already been developed separately, but not integrated together yet. It is the first experience to combine all the components, including core software for a front-end IO controller, an EPICS run-time database, and a remote graphic user interface. This paper describes the detail of the recent construction status of the L3BT control system, including component development, system integration, and device commissioning.
observed by neutron diffraction measurementsArai, Shigeki; Chatake, Toshiyuki*; Ohara, Takashi; Kurihara, Kazuo; Tanaka, Ichiro*; Suzuki, Nobuhiro*; Fujimoto, Zui*; Mizuno, Hiroshi*; Niimura, Nobuo
Nucleic Acids Research, 33(9), p.3017 - 3024, 2005/05
Times Cited Count：93 Percentile：82.96(Biochemistry & Molecular Biology)It has long been suspected that the structure and function of a DNA duplex can be strongly dependent on its degree of hydration. By neutron diffraction experiments, we have succeeded in determining most of the hydrogen (H) and deuterium (D) atomic positions in the d(CCATTAATGG) duplex. Moreover, the D positions in 27 DO molecules have been determined. In particular, the complex water network in the minor groove has been observed in detail. By a combined structural analysis using 2.0 Å resolution X-ray and 3.0 Å resolution neutron data, it is clear that the spine of hydration is built up, not only by a simple hexagonal hydration pattern (as reported in prior X-ray studies), but also by many other water bridges hydrogen-bonded to the DNA strands. The complexity of the hydration pattern in the minor groove is derived from an extraordinary variety of orientations displayed by the water molecules.
Hanamuro, Takahiro; Saito, Hiroshi; Asamori, Koichi; Iyatomi, Yosuke; Tsuruta, Tadahiko; Yabuuchi, Satoshi; Mizuno, Takashi; Sato, Toshinori; Nakatsuka, Noboru; Shigeta, Naotaka; et al.
JNC TN7400 2004-010, 173 Pages, 2004/12
JNC-TN7400-2004-010.pdf:41.03MB
Japan Nuclear Cycle Development Institute. (JNC) is developing two underground research laboratory projects; the Mizunami Underground Research Laboratory(MIU) Project for crystalline rock,.at Tono Geoscience Center (TGC) and the Horonobe Underground Research Laboratory ・Project for・ sedimentary rock at the Horonobe Underground Research Center. Both projects are intended for research and development of geological disposal technology for high-level radioactive wastes. At this time, these two underground research laboratory projects are advancing to the Construction Phase (Phase II) from the Surface-based Investigation Phase (Phase I). Therefore it was considered appropriate for JNC to hold an international conference to introduce the two underground research laboratory projects and R&D results from Phase I, to have presentations on overseas URLs, to exchange opinions by researchers in each field of research and to reflect the conference outcome in a future R&D plan. The Conference was held in two parts. Part 1, the "International Conference on Geoscientific Study in Mizunami '04 (ICGM '04)" featured the MIU Project and the Regional Hydrogeological Study Project performed by TGC. It was held in Mizunami City at the Sogo Bunka Center from October 21st to 22nd. In Part 2, the "International Workshop on Horonobe Underground Research Laboratory Project", featured the Horonobe Underground Research Laboratory Project performed by the Horonobe Underground Research Center. It was held at Horonobe Town Hall from, October 25th to 26th 2004. This Technical Report documents the ICGM'04 program, abstracts of presentations and slides and transcription of "Panel Discussions II and "Summary of the Conference"
Konomura, Mamoru; Ogawa, Takashi; Okano, Yasushi; Yamaguchi, Hiroyuki; Murakami, Tsutomu; Takaki, Naoyuki; Nishiguchi, Youhei; Sugino, Kazuteru; Naganuma, Masayuki; Hishida, Masahiko; et al.
JNC TN9400 2004-035, 2071 Pages, 2004/06
JNC-TN9400-2004-035.pdf:76.42MB
The attractive concepts for Sodium-, lead-bismuth-, helium- and water-cooled FBRs have been created through using typical plant features and employing advanced technologies. Efforts on evaluating technological prospects of feasibility have been paid for these concepts. Also, it was comfirmed if these concepts satisfy design requierments of capability and performance presumed in the feasibilty study on commertialization of Fast Breeder Reactor Systems. As results, it was concluded that the selection of sodium-cooled reactor was most rational for practical use of FBR technologies in 2015.
Arai, Shigeki; Chatake, Toshiyuki; Suzuki, Nobuhiro*; Mizuno, Hiroshi*; Niimura, Nobuo
Acta Crystallographica Section D, 60(6), p.1032 - 1039, 2004/06
Times Cited Count：17 Percentile：76.04(Biochemical Research Methods)The parameters used for evaluating biomacromolecular crystal quality (
, 
/
(), maximum resolution and mosaicity) strongly depend on the diffraction experimental conditions. In this paper we describe the distinctive features of the relative Wilson plot method, and we show that the overall B-factor obtained from this plot is given as a more appropriate to characterize protein crystals. The relative Wilson plot has been applied to the characterization of crystals of a B-DNA decamer d(CCATTAATGG), and crystals of the proteins DsrD (dissimilatory sulfite reductase D) and hen egg-white lysozyme (HEWL) which we have studied by neutron diffraction. We have found that the crystal qualities of the B-DNA decamer and DsrD significantly depend on the regions of the crystallization phase diagram from which samples were taken. However, in the case of HEWL, crystal quality appears to be independent on the region of the crystallization phase diagram.
Kuriyama, Masaaki; ; Araki, Masanori; ; Hanada, Masaya; Inoue, Takashi; Kawai, Mikito; Kazawa, Minoru; *; Kunieda, Shunsuke; et al.
Fusion Engineering and Design, 26, p.445 - 453, 1995/00
Times Cited Count：43 Percentile：95.65(Nuclear Science & Technology)no abstracts in English
Kuriyama, Masaaki; Kunieda, Shunsuke; Matsuoka, Mamoru; Mizuno, Makoto; Ohara, Yoshihiro; Ohara, Hiroshi; Mogaki, Kazuhiko
JAERI-M 93-059, 13 Pages, 1993/03
no abstracts in English
Kuriyama, Masaaki; ; Araki, Masanori; ; Hanada, Masaya; Inoue, Takashi; Kawai, Mikito; Kazawa, Minoru; *; Kunieda, Shunsuke; et al.
15th IEEE/NPSS Symp. on Fusion Engineering,Vol. 1, 0, p.470 - 473, 1993/00
no abstracts in English
Kuriyama, Masaaki; Ohara, Yoshihiro; ; ; Hanada, Masaya; Inoue, Takashi; *; *; Ito, Takao; Kawai, Mikito; et al.
Fusion Technology 1992, Vol.1, p.564 - 568, 1993/00
no abstracts in English
Matsuoka, Mamoru; Horiike, Hiroshi; Ito, Takao; Kawai, Mikito; Kikuchi, Mitsuru; Kuriyama, Masaaki; Mizuno, Makoto; Tanaka, Shigeru
Fusion Technology, 19, p.113 - 130, 1991/01
no abstracts in English
