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Nakashima, Koichi*; Onagi, Kaito*; Kobayashi, Yoshio*; Ishigaki, Toru*; Ishikawa, Yoshihisa*; Yoneda, Yasuhiro; Yin, S.*; Kakihana, Masato*; Sekino, Toru*
ACS Omega (Internet), 6(14), p.9410 - 9425, 2021/04
Times Cited Count:10 Percentile:55.19(Chemistry, Multidisciplinary)We succeeded in synthesizing barium titanate nanocubes by hydrothermal synthesis. When the nanocubes were examined in detail using a scanning electron microscope, pulsed neutrons, and large synchrotron radiation, it was found that a reconstituted layer of titanium oxide was formed on the surface.
Xu, P. G.; Hoshikawa, Akinori*; Hayashi, Makoto*; Akita, Koichi; Morii, Yukio*; Ishigaki, Toru*
Nihon Zairyo Gakkai Dai-48-Kai X Sen Zairyo Kyodo Ni Kansuru Shimpojiumu Koen Rombunshu, p.7 - 9, 2014/07
Yanagizawa, Koichi; Hayashi, Toshio*; Oinuma, Masaru*; Takemori, Makoto*; Ishikawa, Takanori*; Okaya, Tomoichi*; Nishigaki, Makoto*
Shadan Hojin Butsuri Tansa Gakkai Dai-129-Kai (Heisei-25-Nendo Shuki) Gakujutsu Koenkai Koen Rombunshu, p.287 - 288, 2013/10
The development of instrument aimed at the measurement of radiation dose in the sediment of lakes, rivers and sea bed been carried out. The radiation level contained in the sediment at the bottom of lake and so on is anticipated to indicate the existence of locally high radiation spots where the diffused radioactive substance is accumulated in ponds, rivers and lakes by rainwater. The radiation dose measurement system this time is to measure -ray by dragging the detector, which is called probe, at the bottom of lakes to understand the radiation dose over wide areas. Furthermore, the measurement of resistivity value at the bottom of lakes is simultaneously dose to presume the condition of sediment.
Ishigaki, Masahiro; Shirai, Koichiro*; Adachi, Shizuko*; Ishii, Katsuya*
AIP Conference Proceedings 1474, p.295 - 298, 2012/09
no abstracts in English
Hodotsuka, Yasuyuki; Matsuoka, Toshiyuki; Tsuruta, Tadahiko; Yamada, Nobuto*; Ishigaki, Koichi*; Yamaguchi, Shinji*
Shadan Hojin Butsuri Tansa Gakkai Dai-119-Kai (Heisei-20-Nendo Shuki) Gakujutsu Koenkai Koen Rombunshu, p.61 - 64, 2008/10
Seismic interferometry using the vibration under the construction works such as borehole drilling, mucking, blasting etc., had been carried out to develop the method that obtain three-dimensional geological image, around the Mizunami Underground Research Laboratory. In this study, we discussed the applicability of this method analytical accuracy depending on vibration resource types.
Matsuoka, Toshiyuki; Hodotsuka, Yasuyuki; Tsuruta, Tadahiko; Ishigaki, Koichi*; Yamada, Nobuto*; Yamaguchi, Shinji*
Shadan Hojin Butsuri Tansa Gakkai Dai-119-Kai (Heisei-20-Nendo Shuki) Gakujutsu Koenkai Koen Rombunshu, p.65 - 67, 2008/10
A reverse VSP (R-VSP) using the blasting vibration been carried out to obtain three-dimensional geological image around the Mizunami Underground Research Laboratory under the shaft excavation works. In this study, the applicability of this method was discussed.
Hodotsuka, Yasuyuki; Matsuoka, Toshiyuki; Ishigaki, Koichi*
Nihon Oyo Chishitsu Gakkai Heisei-19-Nendo Kenkyu Happyokai Koen Rombunshu, p.213 - 214, 2007/10
no abstracts in English
Yamada, Nobuto*; Ishigaki, Koichi*; Yamaguchi, Shinji*; Narita, Norifumi*; Matsuoka, Toshiyuki; Hodotsuka, Yasuyuki; Matsuoka, Toshifumi*
Shadan Hojin Butsuri Tansa Gakkai Dai-117-Kai (Heisei-19-Nendo Shuki) Gakujutsu Koenkai Koen Rombunshu, p.146 - 148, 2007/10
Seismic interferometry synthesizes the Green's function between two receivers by calculating cross-correlation of records measured at their locations. In Japan Atomic Energy Agency(JAEA), Seismic Interferometry using blasting vibration caused by the shafts excavation had been carried out to investigate the geologic structure in the surrounding area. The result was identical to the existing seismic reflection section. In this study, we applied this technique to long time measured microtremor. The result was also identical to the results of existing section and seismic interferometry using blasting vibration caused by the shafts excavation.
Lee, C.*; Matsuoka, Toshiyuki; Ishigaki, Koichi; Tanoue, Masayoshi*; Yamaguchi, Shinji*; Tsuchiya, Terumitsu*; Matsuoka, Toshifumi*
Proceedings of 11th International Symposium on Recent Advances in Exploration Geophysics (RAEG 2007), p.69 - 71, 2007/04
Image Points are defined through geometry of sources, receivers and reflectors. IP (Image Point) transform is one type of Radon transform which change common shot section to IP domain (r-x). By the IP transform, reflection signals in time domain can be accumulated and enhanced in IP domain. We applied the IP transform to the field data of RVSP that had been carried out at the Mizunami Underground Research Laboratory (MIU) site. We could get the fault image around the MIU site using IP transform.
Matsuoka, Toshiyuki; Semba, Takeshi; Ishigaki, Koichi; Sugimoto, Yoshihiro*; Tanoue, Masayoshi*; Narita, Norifumi*
Nihon Oyo Chishitsu Gakkai Heisei-18-Nendo Kenkyu Happyokai Koen Rombunshu, p.331 - 334, 2006/11
no abstracts in English
Lee, C.*; Matsuoka, Toshiyuki; Ishigaki, Koichi; Tanoue, Masayoshi*; Narita, Norifumi*; Kojima, Masakazu*; Tsuchiya, Terumitsu*; Matsuoka, Toshifumi*
Proceedings of 10th International Symposium on Recent Advances in Exploration Geophysics (RAEG 2006), p.143 - 146, 2006/00
It is known that 3-D Vertical Seismic Profile (VSP) method has an advantage on imaging the fault and fracture zone near the borehole, especially steeply dipped structure. Cosma et al (2003) has developed the new technique named Image Point Transform (IP Transform) and applied to offset VSP data to improve the week reflection signals from the steeply dipped fracture. We test the applicability of this method to the 3-D Reverse VSP data of numerical simulation and develop the method of imaging named spectral operator of middle point of IP. In the results of applying to 3-D model of steeply dipped fracture, we know that this method is applicable to 3-D reverse VSP data and could get the good image of fracture reconstructed by spectral operator of middle point of IP.
Matsuoka, Toshiyuki; Hodotsuka, Yasuyuki; Ishigaki, Koichi*; Lee, C. H.*
no journal, ,
We carried out R-VSP using vibrations caused by blasting for the shaft excavation and drilling of the borehole investigation in the horizontal research galleries of the MIU, and examined the applicability of this method to imaging of geological structures around underground facilities, such as boundary between sedimentaly rocks and basal granite, fault and fracture zone in basal granite. As the results, the reflective events that seemed to correspond with sedimentary layers, the unconformity between sedimentaly rocks and granite, and fracture zone in granite could be confirmed by reflection profiles using the conventional VSP data processing and Seismic interferometry. From data processing by Image Point transform, the distribution of three faults, that are correspondent with the current geological model constructed from investigation data in the MIU project, could be detected.
Xu, P. G.; Hoshikawa, Akinori*; Ishigaki, Toru*; Hayashi, Makoto*; Minemura, Tetsuro*; Harjo, S.; Akita, Koichi
no journal, ,
Ishigaki, Koichi; Matsuoka, Toshiyuki; Amano, Kenji
no journal, ,
no abstracts in English
Xu, P. G.; Hoshikawa, Akinori*; Ishigaki, Toru*; Suzuki, Tetsuya*; Akita, Koichi; Morii, Yukio*; Hayashi, Makoto*; Lutterotti, L.*
no journal, ,
Shirai, Koichiro*; Ishii, Katsuya*; Ishigaki, Masahiro
no journal, ,
Taconis oscillations, which are spontaneous oscillations of a gas column in a tube with cold and hot walls, are studied numerically. We use axisymmetric compressible Navier-Stokes equations. The spontaneous oscillations are observed in the closed tube when the temperature ratios of hot part to cold part are more than a critical value. We observed three types of oscillation modes when the length ratios of hot part to cold part is 0.3. The oscillation states of fundamental mode and second mode are observed in the region upside the critical temperature ratios of Rott's theory.
Shirai, Koichiro*; Ishii, Katsuya*; Ishigaki, Masahiro
no journal, ,
no abstracts in English
Matsuoka, Toshiyuki; Ishigaki, Koichi; Sugimoto, Yoshihiro*
no journal, ,
no abstracts in English
Yamada, Nobuto; Matsuoka, Toshiyuki; Ishigaki, Koichi*; Kanazawa, Yohei*; Tokuyasu, Shingo*; Nakahara, Junichi*
no journal, ,
Evaluation on the geological discontinuity is one of the important issues for safety assessment of high-level radioactive waste disposal. A Reverse Vertical Seismic Profiling (RVSP) investigation using blasting vibration for excavation of the research gallery and survey lines placed in the -300m research galleries of the Mizunami Underground Research Laboratory has been carried out to obtain three-dimensional information on the geological discontinuity such as faults and fracture zones in granite during the research galleries excavation works. In this study, results of RVSP are compared with existing information such as sonic logging to estimate spatial distribution of faults and fracture zones, and the applicability of this method to estimate geological structure in the granite is discussed.
Xu, P. G.; Hoshikawa, Akinori*; Ishigaki, Toru*; Suzuki, Tetsuya*; Akita, Koichi; Morii, Yukio*; Hayashi, Makoto*; Lutterotti, L.*
no journal, ,