Watanabe, Takahiro; Ishii, Chikako; Ishizaka, Chika; Niwa, Masakazu; Shimada, Koji; Sawai, Yuki*; Tsuchiya, Noriyoshi*; Matsunaka, Tetsuya*; Ochiai, Shinya*; Nara, Fumiko*
Journal of Mineralogical and Petrological Sciences, 116(3), p.140 - 158, 2021/00
A portable energy dispersive X-ray fluorescence spectrometer (potable XRF) can be an effective tool for detecting chemical elements in various materials, such as geological, and environmental samples. In this study, working curves were confirmed using reference materials, such as igneous rocks and other geochemical standards, distributed by national and international organizations. Subsequently, quantification and semi-quantification analyses were performed by the portable XRF for inorganic elements in (A) fault rocks, (B) lake sediments from the middle Japan, and (C) soils with paleotsunami deposits from the Pacific coast of northeast Japan. Twenty-four elements (Mg-U) in these geological samples were measured by potable XRF using our working curves. Measured values by the portable XRF of the samples were good agreement with the reported values in almost cases.
Hirayama, Yoshikazu*; Mihara, Mototsugu*; Watanabe, Yutaka*; Jeong, S. C.*; Miyatake, Hiroari*; Momota, Sadao*; Hashimoto, Takashi*; Imai, Nobuaki*; Matsuta, Kensaku*; Ishiyama, Hironobu*; et al.
European Physical Journal A, 48(5), p.54_1 - 54_10, 2012/05
Endo, Kiyoshi*; Shibata, Yasushi*; Yamamoto, Tetsuya*; Nakai, Kei*; Matsumura, Akira*; Sato, Takahiro; Yokoyama, Akihito; Koka, Masashi; Okubo, Takeru; Yamazaki, Akiyoshi; et al.
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 86, 2012/01
Tokiwa, Tetsuya; Tsusaka, Kimikazu; Ishii, Eiichi; Sanada, Hiroyuki; Tominaga, Eiji*; Hatsuyama, Yoshihiro*; Funaki, Hironori
International Journal of Rock Mechanics and Mining Sciences, 48(5), p.773 - 781, 2011/07
This paper focuses attention on stress field that produced fault system, and presents an example of the relationship between fault system and rock mass response to shaft excavation in soft sedimentary rocks in the Horonobe area, Japan. The directions determined by fault-slip analysis are close to the direction of maximum and minimum diameter reduction in the shaft. The results show that fault system can affects rock mass response to shaft excavation in soft rock and furthermore, and it is considered that the rock mass deformation was controlled by fault system. In addition, it is likely that we can assess and predict rock mass behavior by focusing on palaeo-stress field that produced fault system.
Ishii, Eiichi; Funaki, Hironori; Tokiwa, Tetsuya; Ota, Kunio
Journal of Structural Geology, 32(11), p.1792 - 1805, 2010/11
In order to assess influences of a remote mean stress on a principal mode of failure near fault tips due to fault slip in a lithologically homogeneous, fractured rock mass, the growth mechanisms of strike-slip faults on outcrop-scale in the siliceous mudstones of northern Hokkaido, Japan, have been studied. A multifaceted approach combining geological characterizations of fractures, rock mechanical characterizations, and theoretical analyses have been done, which suggested (1) the principal mode of failure depend on not only the rock strengths, but also the remote mean stresses, (2) during and/or after uplift and erosion the faults grew mainly by linking with adjacent faults via many splay cracks which are formed by tensile failure above roughly 400 m depth, while, below the depth, the faults predominantly grew by shear failure. Such growth mechanisms are consistent with the fact that highly permeable sections are restricted to depths of less than 400 m.
Toyoshima, Atsushi; Kasamatsu, Yoshitaka*; Tsukada, Kazuaki; Asai, Masato; Ishii, Yasuo; Tome, Hayato*; Nishinaka, Ichiro; Sato, Tetsuya; Nagame, Yuichiro; Schdel, M.; et al.
Journal of Nuclear and Radiochemical Sciences, 11(1), p.7 - 11, 2010/06
The extraction behavior of rutherfordium (Rf) into trioctylphosphine oxide (TOPO) from 2.0 - 7.0 M HCl solution was studied together with that of the homologues Zr and Hf. The extracted yields of Rf, Zr, and Hf increased with an increase of HCl concentration, and the sequence of their extraction was Zr Hf Rf. It is suggested that the stability of the RfCl2(TOPO) complex is lower than that of the corresponding species of the homologues.
Ishii, Tetsuya; Yoshimochi, Hiroshi; Tanaka, Kenya
Nihon Genshiryoku Gakkai Wabun Rombunshi, 9(2), p.207 - 218, 2010/06
In order to develop an innovative fuel fabrication method for americium containing oxide fuels, a feasibility study of metallic U and Mo-doped oxide fuel concept with extruding granulated oxide material was conducted using UO. In the concept, it is expected that doped U should reduce the effective oxygen potential and doped Mo should increase the thermal conductivity of the fuel. In this study, sintering tests of U and Mo-doped UO powder were done and thermal conductivities of the sintered material were evaluated. From the results, it can be seen that the doped U and Mo would function as a oxygen potential reducer and thermal conductivity improver, respectively. And it can be seen that the U and Mo doped oxide fuel pellets would be fabricated successfully using hot pressing. Also, from the results of a sintering test of U and Mo-doped extruding granulated UO, it can be seen that the extruding granulated substances have a preferable sintering characteristic.
Nagae, Daisuke*; Ishii, Tetsuro; Takahashi, Ryuta*; Asai, Masato; Makii, Hiroyuki; Osa, Akihiko; Sato, Tetsuya; Ichikawa, Shinichi; Shimizu, Yoshifumi*; Shoji, Takuya*
AIP Conference Proceedings 1224, p.156 - 160, 2010/04
Sakashita, Tetsuya; Takanami, Takako*; Yanase, Sumino*; Hamada, Nobuyuki*; Suzuki, Michiyo; Kimura, Takafumi*; Kobayashi, Yasuhiko; Ishii, Naoaki*; Higashitani, Atsushi*
Journal of Radiation Research, 51(2), p.107 - 121, 2010/03
The study of radiation effect in have been carried out over three decades and now allow for understanding at the molecular, cellular and individual levels. This review describes the current knowledge of the biological effects of ionizing irradiation with a scope of the germ line, aging and behavior. may be a good model system in the field of radiation biology.
Tokiwa, Tetsuya; Ishii, Eiichi; Funaki, Hironori; Tsusaka, Kimikazu; Sanada, Hiroyuki
Proceedings of 3rd International Workshop and Conference on Earth Resources Technology 2009 (CD-ROM), p.159 - 168, 2009/12
Japan Atomic Energy Agency has been constructing underground facilities since 2005 in the Horonobe area. Before the construction, the rock stress was measured by the hydraulic fracturing method using boreholes. In this area, the result showed that the direction of the major horizontal principal stress was in E-W direction. On the other hand, in shaft excavation, the direction of the predominant diameter reduction was observed in NNE-SSW to NE-SW direction. The difference would be attributed to the fact that fault system in the rock affects the deformation of shaft. The authors applied fault-striation analysis with faults identified on drilling cores. The direction of the major principal stress estimated by fault-striation analysis approximately corresponds to the predominant directions of the deformation caused by the shaft excavation. The result shows that fault system affects rock mass behavior in shaft excavation.
Kasamatsu, Yoshitaka*; Toyoshima, Atsushi; Asai, Masato; Tsukada, Kazuaki; Li, Z.; Ishii, Yasuo; Tome, Hayato*; Sato, Tetsuya; Kikuchi, Takahiro; Nishinaka, Ichiro; et al.
Chemistry Letters, 38(11), p.1084 - 1085, 2009/10
We report on the characteristic anion-exchange behavior of the superheavy element dubnium (Db) with atomic number Z = 105 in HF/HNO solution at the fluoride ion concentration [F] = 0.003 M. The result clearly demonstrates that the fluoro complex formation of Db is significantly different from that of the group-5 homologue Ta in the 6th period of the periodic table while the behavior of Db is similar to that of the lighter homologue Nb in the 5th period.
Funaki, Hironori; Ishii, Eiichi; Tokiwa, Tetsuya
Oyo Chishitsu, 50(4), p.238 - 247, 2009/10
Evaluation of the role of fracture as the major water-conducting feature in sedimentary rocks is indispensable information to carry out the modelling and analysis of the groundwater flow. We conduct core logging, acoustic televiewer logging and fluid electric conductivity logging at a borehole to clarify the relationship between fracture and flow point. As a result, most of the fractures in the Koetoi Formation don't have a function as major water-conducting features, but some of the fractures in the Wakkanai Formation do. The further statistical analysis indicates; (1) fracture interconnectivity in the Koetoi Formation is poor, while that in the Wakkanai Formation exists to some extent, (2) fracture aperture in the Wakkanai Formation tends to be more than that in the Koetoi Formation. These suggest that the Koetoi Formation would be porous medium and the Wakkanai Formation would be stronger in property as fractured medium than the Koetoi Formation.
Tanaka, Kenya; Ishii, Tetsuya; Yoshimochi, Hiroshi; Asaka, Takeo
Proceedings of International Conference on Advanced Nuclear Fuel Cycle; Sustainable Options & Industrial Perspectives (Global 2009) (CD-ROM), p.2045 - 2050, 2009/09
As a part of the economic evaluation of the MA recycling system, the management cost of high level radioactive waste was estimated quantitatively. The development of an innovative fuel fabrication process has been done by using UO powder, U metal particles and Mo powder. From comparisons of granulated material characteristics, two candidate methods, mixing granulation (MIX/G) and extruding granulation (EXT/G), were considered to have good feasibility as the fuel fabrication process. In the preliminary sintering test of granulated UO obtained by EXT/G, a high density UO pellet (97% of TD) with 5wt% of U and 5wt% of Mo was successfully sintered. From the results of thermal conductivity measurements, it was confirmed that the dispersion of Mo powder and U metal into the oxide matrix was an effective way to improve the characteristic.
Iwatsuki, Teruki; Sato, Haruo; Tanai, Kenji; Inagaki, Manabu; Sawada, Atsushi; Niinuma, Hiroaki; Ishii, Eiichi; Maekawa, Keisuke; Tomura, Goji; Sanada, Hiroyuki; et al.
JAEA-Research 2009-002, 156 Pages, 2009/05
The research and development plan for geological investigation, engineering technology and safety assessment during the drilling of a shaft down to intermediate depth are summarized according to the Midterm Plan till 2009 Fiscal year of JAEA. This report describes subject, current status and programme in the "Phase 2: Construction phase" (investigations during construction of the underground facilities). Furthermore regarding R&D plan in next Midterm Plan of JAEA, preliminary ideas are summarized.
Nihon Genshiryoku Gakkai-Shi ATOMO, 51(5), p.366 - 367, 2009/05
no abstracts in English
Funaki, Hironori; Tokiwa, Tetsuya; Ishii, Eiichi; Hatsuyama, Yoshihiro*; Matsuo, Shigeaki*; Tsuda, Kazuyasu*; Koizumi, Akira*; Ishikawa, Taiki*; Daijo, Yuichi*; Sugiyama, Kazutoshi*
JAEA-Data/Code 2008-013, 65 Pages, 2008/08
We conducted geological investigation of the pilot borehole of the ventilation shaft in Horonobe during October 2007 and March 2008. This report describes the field operations (core description, core photograph, and core sampling) and laboratory measurements (modal analysis and X-ray diffraction analysis), equipments as well as processing procedures, and shows the obtained results. The information obtained from this investigation will be reflected in spring water control plan on shaft excavation and additional plan of drainage treatment facilities.
Sakashita, Tetsuya; Hamada, Nobuyuki*; Ikeda, Daisuke*; Suzuki, Michiyo; Yanase, Sumino*; Ishii, Naoaki*; Kobayashi, Yasuhiko
Journal of Radiation Research, 49(3), p.285 - 291, 2008/05
We investigated the effects of ionizing radiation (IR) exposure on the relationship between locomotion and salt chemotaxis learning behavior of . We found that effects of pre-learning irradiation on locomotion were significantly correlated with the salt chemotaxis learning performance, whereas locomotion was not directly related to chemotaxis to NaCl. On the other hand, locomotion was positively correlated with salt chemotaxis of animals which were irradiated during learning, and the correlation disappeared with increasing doses. These results suggest an indirect relationship between locomotion and salt chemotaxis learning in , and that IR inhibits the innate relationship between locomotion and chemotaxis, which is related to salt chemotaxis learning conditioning of .
Ishii, Tetsuya; Nemoto, Junichi*; Asaka, Takeo; Sato, Seichi*; Mayorshin, A.*; Shishalov, O.*; Kryukov, F.*
Journal of Nuclear Science and Technology, 45(4), p.263 - 273, 2008/04
In order to develop a vibro-packed MOX fuel performance analysis code, thermochemical and mechanical properties of the vibro-packed fuels were incorporated into a pellet type fuel performance analysis code CEDAR. Calculations were made by the developed code on a vibro-packed MOX fuel pin irradiated at BN-600 in Russia. Since the calculated results agreed well with the behaviors obtained from the experimental data, it can be concluded that the code was well modeled and qualitatively validated.
Sakashita, Tetsuya; Hamada, Nobuyuki*; Ikeda, Daisuke*; Yanase, Sumino*; Suzuki, Michiyo; Ishii, Naoaki*; Kobayashi, Yasuhiko
FASEB Journal, 22(3), p.713 - 720, 2008/03
We analyzed the effects of ionizing radiation (IR) on a food-NaCl associative learning paradigm of adult , and observed that a decrease in chemotaxis toward NaCl occurs only after combined starvation and exposure to NaCl. Exposure to IR induced an additional decrease in chemotaxis immediately after an acute dose in the transition stage of the food-NaCl associative learning. Strikingly, chronic irradiation induced negative chemotaxis in the exposed animals, i.e., the primary avoidance response. IR-induced additional decreases in chemotaxis following acute and chronic irradiations were significantly suppressed in the mutant, which was defective in GPC-1. Chemotaxis to cAMP, but not to lysine and benzaldehyde, was influenced by IR during the food-NaCl associative learning. Our novel findings suggest that IR behaves as a modulator in the food-NaCl associative learning via GPC-1 and a specific neuronal network.
Toyoshima, Atsushi; Haba, Hiromitsu*; Tsukada, Kazuaki; Asai, Masato; Akiyama, Kazuhiko*; Goto, Shinichi*; Ishii, Yasuo; Nishinaka, Ichiro; Sato, Tetsuya; Nagame, Yuichiro; et al.
Radiochimica Acta, 96(3), p.125 - 134, 2008/03
Formation of an anionic fluoride-complex of element 104, rutherfordium (Rf) produced in the Cm(O,5n)Rf reaction was studied by an anion-exchange method based on an atom-at-a-time scale. It was found that the hexafluoro complex of Rf, [RfF], was formed in the studied fluoride ion concentrations of 0.0005 - 0.013 M. Formation of [RfF] was significantly different from that of the homologues Zr and Hf, [ZrF] and [HfF]; the evaluated formation constant of [RfF] is at least one-order of magnitude smaller than those of [ZrF] and [HfF].