Integration of the geological survey data obtained for shaft and gallery walls from the surface to a depth of 380m in the Horonobe Underground Research Laboratory Project

Sakai, Toshihiro; Hayano, Akira

JAEA-Data/Code 2021-010, 243 Pages, 2021/10

JAEA-Data-Code-2021-010.pdf:62.15MB
JAEA-Data-Code-2021-010-appendix1(CD-ROM).zip:95.55MB
JAEA-Data-Code-2021-010-appendix2(CD-ROM).zip:152.69MB
JAEA-Data-Code-2021-010-appendix3(CD-ROM).zip:25.48MB

The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe, northern Hokkaido. The project consists of two major research areas, "Geoscientific Research" and "R&D on Geological Disposal", and proceeds in three overlapping phases, "Phase I: Surface-based investigation", "Phase II: Construction" and "Phase III: Operation". The geological survey has been carried out at the shafts and the galleries in the Phase II. The geological survey was carried out during the excavation cycle, and the data were obtained for each an excavation cross section. This report shows the data which the individual geological data were integrated for the geological survey at the shafts and the galleries from the surface to a depth of 380m.

The Regional-scale 3D geological model in the Horonobe Underground Research Laboratory Project

Sakai, Toshihiro; Matsuoka, Toshiyuki

JAEA-Data/Code 2019-007, 29 Pages, 2019/09

JAEA-Data-Code-2019-007.pdf:53.07MB
JAEA-Data-Code-2019-007-appendix(CD-ROM).zip:340.04MB

Japan Atomic Energy Agency is performing the Horonobe Underground Research Laboratory Project, which includes a scientific study of the deep geological environment as a basis of research and development for the geological disposal of high level radioactive wastes, in order to establish comprehensive techniques for the investigation, analysis and assessment of the deep geological environment in the sedimentary rock. This report summarize numerical data of 3D geological model in regional-scale constructed by Maptek Vulcan.

Development of geological models in the Mizunami Underground Research Laboratory Project; Updating from "Shaft500 Geological Model" to "Stage500 Geological Model" in Phase II

Sakai, Toshihiro; Nohara, Tsuyoshi; Ishibashi, Masayuki

JAEA-Research 2016-009, 27 Pages, 2016/07

JAEA-Research-2016-009.pdf:4.05MB

In the Phase II, the geophysical and geological surveys, and the borehole investigation of the research galleries were carried out and the results obtained were used to validate and update the geological model. Through these surveys and analysis work, we confirmed the geological properties and the distribution of model components and evaluated the accuracy of these research methods. This report presents the geological model updated based on the information of the distributions of lithofacies and geological structures at a depth 500m research galleries, and besides, the validity of the geological model of the site scale developed in the Phase I is confirmed by comparing with the updated model.

Presumption of the distribution of the geological structure based on the geological survey and the topographic data in and around the Horonobe area

Sakai, Toshihiro; Matsuoka, Toshiyuki

JAEA-Research 2015-004, 109 Pages, 2015/06

JAEA-Research-2015-004.pdf:141.42MB
JAEA-Research-2015-004-appendix(CD-ROM).zip:128.66MB

We update the geologic map and the database of the geological mapping published by Funaki et al. (2005a) and Ota et al. (2007) based on geological survey and topographical analysis data in and around the Horonobe area. There are many geological survey data which are derived from natural resources (petroleum, natural gas and coal, etc.) exploration in and around Horonobe-cho. We also use these data in addition to data in Funaki et al. (2005a) and Ota et al. (2007)'s data. As results of this report, we also construct a digital geologic map and a digital database of geological survey using GIS. These results can be expected to improve the precision of modeling and analyzing of geological environment, and its long-term evaluation.

In-plane orientation control of 2,7-diphenyl[1]benzothieno[3,2-][1]benzothiophene monolayer on bismuth-terminated Si(111) vicinal surfaces with wettability optimization

Otomo, Manabu; Tsuchida, Yuya*; Muraya, Naoki*; Yanase, Takashi*; Sakai, Seiji; Yonezawa, Tetsu*; Nagahama, Taro*; Hasegawa, Tetsuya*; Shimada, Toshihiro*

Journal of Physical Chemistry C, 117(22), p.11555 - 11561, 2013/06

https://doi.org/10.1021/jp3117837

We report in-plane orientation control of newly developed high-mobility organic semiconductor: 2,7-diphenyl[1]benzothieno[3,2-][1]benzothiophene (DPh-BTBT). As previously reported on monolayer pentacene, it was revealed that bunched steps on vicinal Si(111) with bismuth termination break the surface symmetry and reduce three-fold symmetry of DPh-BTBT grains into quasi-single orientation. Interestingly, the critical step height necessary for the orientation control was different from that of pentacene. We examined several mechanisms of orientation control and concluded that the facet nano structure fabricated by step bunching is working as an anisotropic template. We will also show the wettability control of bismuth terminated silicon surface and show that the growth mode of DPh-BTBT is dependent on the surface nanostructure of Bi-Si.

X-ray absorption spectroscopy and magnetic circular dichroism in codeposited C-Co films with giant tunnel magnetoresistance

Matsumoto, Yoshihiro; Sakai, Seiji; Takagi, Yasumasa*; Nakagawa, Takeshi*; Yokoyama, Toshihiko*; Shimada, Toshihiro*; Mitani, Seiji*; Naramoto, Hiroshi*; Maeda, Yoshihito

Chemical Physics Letters, 470(4-6), p.244 - 248, 2009/03

https://doi.org/10.1016/j.cplett.2009.01.032

Electronic and spin states of the codeposited C-Co films with large tunnel magnetoresistance (TMR) effect were investigated with the X-ray absorption and magnetic circular dichroism (MCD) spectroscopies. It is revealed that a C-Co compound generated in the C-Co films shows the clear MCD signal attributed to the spin-polarized Co 3d states hybridized with C orbitals. The magnetic response of these Co 3d-derived states agrees well with temperature dependence of the observed MR ratios of the granular C-Co films. This suggests the incorporation of the spin-polarized Co 3d-derived states of the C-Co compound into the observed TMR effect.

The Electronic structures of fullerene/transition-metal hybrid material

Matsumoto, Yoshihiro; Sakai, Seiji; Naramoto, Hiroshi*; Hirao, Norie*; Baba, Yuji; Shimada, Toshihiro*; Sugai, Isamu; Takanashi, Koki; Maeda, Yoshihito

Materials Research Society Symposium Proceedings, Vol.1081 (Internet), 6 Pages, 2008/03

Recently, we have found the appearance of substantial MR ratio (80%) in a C/Co hybrid material. Such the MR ratio cannot be explained enough only by tunnel conduction through Co grains. Therefore, to obtain information about electronic structures of C/Co hybrid material is necessary. Absorption spectra of CCo are different from that of pristine C. In particular, peak intensity corresponding to (LUMO) C 1s excitation of CCo is clearly attenuated. In addition, C 1s photoelectron peak of CCo slightly shifted to lower binding energy compared to that of pristine C. These results indicate that 3d electron of Co transfers to orbital of C and new electronic states are formed in the C-Co compound. In fact, XPS spectra of valence excitation region also demonstrate the formation of hybrid orbital near the Fermi level due to the coupling of C and Co.

Development of a criticality evaluation method considering the particulate behavior of nuclear fuel

Sakai, Mikio; Yamamoto, Toshihiro; Murazaki, Minoru; Miyoshi, Yoshinori

Nuclear Technology, 149(2), p.141 - 149, 2005/02

https://doi.org/10.13182/NT05-A3586

In the conventional criticality evaluation of the nuclear powder system, the effects of particulate behavior have not been considered. In other words, it is difficult to reflect the particle behavior into the conventional criticality evaluation. We have developed a novel criticality evaluation code to resolve this issue. The criticality evaluation code, coupling a Discrete Element Method simulation code with a continuous-energy Monte Carlo transport code, makes it possible to study the effect of the particulate behavior on a criticality evaluation. The criticality evaluation code has been applied to the powder system of the MOX fuel powder agitation process. The criticality evaluations have been performed under mixing the MOX fuel powder in a stirred vessel to investigate the effects of the powder boundary deformation and particulate mixture conditions on the criticality evaluation. The evaluation results revealed that the powder uniformity mixture condition and the boundary deformation could make the neutron effective multiplication factor decrease.

Giant TMR effect and spin states of C-Co thin films

Sakai, Seiji; Matsumoto, Yoshihiro; Sugai, Isamu*; Mitani, Seiji*; Takanashi, Koki; Takagi, Yasumasa*; Nakagawa, Takeshi*; Yokoyama, Toshihiko*; Shimada, Toshihiro*; Maeda, Yoshihito

no journal, , 

no abstracts in English

Soft X-ray circular dichroism study of electronic and magnetic states in C-Co mixture film

Matsumoto, Yoshihiro; Sakai, Seiji; Naramoto, Hiroshi*; Nakagawa, Takeshi*; Takagi, Yasumasa*; Yokoyama, Toshihiko*; Takanashi, Koki; Mitani, Seiji*; Shimada, Toshihiro*; Maeda, Yoshihito

no journal, , 

no abstracts in English