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Oguri, Kaori; Hagura, Naoto*; Yamaguchi, Akiko; Okumura, Masahiko; Matsuura, Haruaki*; Tsunashima, Yasumichi; Aoki, Katsumi; Arai, Yoichi; Watanabe, So
Nuclear Instruments and Methods in Physics Research B, 556, p.165516_1 - 165516_8, 2024/11
Times Cited Count:0 Percentile:0.00(Instruments & Instrumentation)Ningyo-toge is the uranium mine that has been operated in Japan. Various radioactive elements such as Uranium (U), and Radium (Ra) are still present in the mine ground water with very small amount, and behavior of those elements is not fully understood. In this study, we investigated the composition of metal oxides and clay minerals in a soil of slag deposit at the mine, and systematics of adsorption structure of various ions were examined. Identifying the composition and chemical forms of minerals present in the soil of slag can provide useful information for the safety assessment and evaluation of influence on the surrounding environment.
Honda, Mitsunori; Kaneta, Yui; Muraguchi, Masakazu*; Hayakawa, Kosetsu*; Oda, Masato*; Iino, Chiaki*; Ishii, Hiroyuki*; Goto, Takuya*
AIP Advances (Internet), 14(5), p.055034_1 - 055034_6, 2024/05
Times Cited Count:0 Percentile:0.00(Nanoscience & Nanotechnology)This study examines the utilization of Fukushima weathered biotite(WB)as an alternative to conventional thermoelectric materials traditionally derived from rare and toxic substances. WB underwent milling, classification, and subsequent heat treatment via molten-salt treatment to produce crystals exhibiting conductivity akin to semiconductors within from 650C to 850
C range. Evaluation of WB and the derived crystal's electrical conductivity and Seebeck coefficient showcased their viability for high-temperature thermoelectric applications. Consequently, WB attained a dimensionless figure of merit (ZT) of 0.015, signaling its potential as a thermoelectric material that surpasses 650
C.
Micheau, C.; Ueda, Yuki; Motokawa, Ryuhei; Bauduin, P.*; Girard, L.*; Diat, O.*
Langmuir, 39(31), p.10965 - 10977, 2023/07
Times Cited Count:9 Percentile:73.37(Chemistry, Multidisciplinary)Mitsuguchi, Takehiro; Minakata, Keiji*; Sugihara, Kaoru*; Hiraoka, Masanori*; Yoshida, Masaaki*; Kokubu, Yoko
bioRxiv (Internet), 55 Pages, 2022/11
Kobayashi, Keita; Yamaguchi, Akiko; Okumura, Masahiko
Applied Clay Science, 228, p.106596_1 - 106596_11, 2022/10
Times Cited Count:9 Percentile:70.29(Chemistry, Physical)no abstracts in English
Okumura, Masahiko
Chikyu Kagaku, 55(4), p.110 - 121, 2021/12
no abstracts in English
Kitagaki, Toru
Journal of Nuclear Materials, 557, p.153254_1 - 153254_8, 2021/12
Times Cited Count:1 Percentile:10.40(Materials Science, Multidisciplinary)Okamoto, Yoshihiro; Osugi, Takeshi; Shiwaku, Hideaki; Akabori, Mitsuo*
Insights Concerning the Fukushima Daiichi Nuclear Accident, Vol.4; Endeavors by Scientists, p.285 - 294, 2021/10
The transfer behavior of cesium adsorbed on some clay minerals in aqueous solution was investigated by X-ray absorption fine structure (XAFS) analysis of the Cs K-edge. The sample was prepared by mixing Cs-adsorbed mineral with a different pure clay mineral in water. The XAFS results of the dried mixture powder were compared with those obtained before mixing. It was recognized from the XAFS analysis for three kinds of clay minerals illite, kaolinite and vermiculite, that cesium was transferred from kaolinite to illite and vermiculite, and from illite to vermiculite. It can be concluded that cesium is transferred to and accumulated in vermiculite.
Fukuda, Tatsuya*; Takahashi, Ryo*; Hara, Takuhi*; Ohara, Koji*; Kato, Kazuo*; Matsumura, Daiju; Inaba, Yusuke*; Nakase, Masahiko*; Takeshita, Kenji*
Journal of Nuclear Science and Technology, 58(4), p.399 - 404, 2021/04
Times Cited Count:7 Percentile:56.33(Nuclear Science & Technology)Yonaga, Yusuke; Sano, Naomi*; Amamiya, Hiroki*; Ogita, Yasuhiro; Niwa, Masakazu; Yasue, Kenichi*
Oyo Chishitsu, 62(1), p.2 - 12, 2021/04
Provenance analysis based on quick identification of heavy minerals using an electron probe microanalyzer (EPMA) was applied to samples from Pleistocene sediments in Horonobe region, Hokkaido, where major provenance rocks can be sedimentary and mafic igneous rocks. The concentrations of 16 elements were measured in individual grains to identify the mineral species based on their chemical composition. In addition, microscopic observation of thin sections and gravel composition analysis were conducted to confirm the validity of the quick identification of heavy minerals. These analyses clarify that combinations of several heavy mineral species can be a useful index of provenance rocks from the Soya Hill and Teshio Mountains, and suggest that uplift of the Soya Hill after ca. 1.5 Ma constrained supply of sediments from the Teshio Mountains. On the other hand, minerals uncommon both in the Soya Hill and Teshio Mountains, such as hornblende, are included in the Pleistocene sediments. This suggests that a sediment supply from distant area was also significant, like transportation by the Teshio River. The method for quick identification of heavy minerals using EPMA can provide an information about provenance rocks difficult to identify only by gravel composition analysis.
Nagashima, Mariko*; Armbruster, T.*; Akasaka, Masahide*; Sano, Asami; Nishio-Hamane, Daisuke*; Malsy, A.*; Imaoka, Teruyoshi*; Nakashima, Kazuo*
Physics and Chemistry of Minerals, 47(6), p.29_1 - 29_18, 2020/06
Times Cited Count:4 Percentile:17.17(Materials Science, Multidisciplinary)Three non-metamict chevkinite-subgroup minerals, from Cape Ashizuri, Japan, Tangir Valley, Diamar District, Pakistan and Haramosh Mts., Skardu district, Pakistan, were studied by crystal chemical techniques. Powder X-ray diffraction and transmission electron microscopic observations confirmed well crystalline samples. Electron-microprobe analyses indicated the general composition known for chevkinite-(Ce). Site scattering values determined by single-crystal X-ray structure refinements suggested assignment of subordinate Nb to the octahedral M3 and M4 sites, minor Th to M1 for the Ashizuri sample and minor Mg to M1 for both samples from Pakistan. Neutron time-of-flight powder diffraction studies were applied to determine the Ti/Fe distribution among octahedral sites for all samples and Mossbauer spectroscopy served for the Fe valence assignment at the four octahedral sites. The dominant iron valence at M1 of the Haramosh sample is ferric whereas for samples Nos. 1 and 2 iron is ferrous.
Hagiwara, Hiroki; Konishi, Hiromi*; Nakanishi, Takahiro; Fujiwara, Kenso; Iijima, Kazuki; Kitamura, Akihiro
Journal of Environmental Radioactivity, 211, p.106042_1 - 106042_10, 2020/01
Times Cited Count:3 Percentile:10.80(Environmental Sciences)Kimura, Tatsuki*; Kozai, Naofumi; Sakamoto, Fuminori; Fukutani, Satoshi*; Ikegami, Maiko*
Doboku Gakkai Rombunshu, G (Kankyo) (Internet), 76(7), p.III_375 - III_382, 2020/00
no abstracts in English
Yokoyama, Tatsunori
Isotope News, (764), p.11 - 14, 2019/08
no abstracts in English
Mihara, Morihiro; Harasawa, Shuichi*; Torii, Kazuyuki*
Genshiryoku Bakkuendo Kenkyu (CD-ROM), 26(1), p.15 - 23, 2019/06
Hardened cement pastes (HCPs) of water/cement ratio (W/C) 50% and 30% using fly ash (FA), blast furnace slag (BFS) and silica fume (SF) for 28 days were prepared. Apparent diffusion coefficients (D) of Cs and I in HCPs were obtained using electron probe microanalysis. For Cs, BFS and SF contributed to a reduction of D
for W/C=50% and 30%, respectively. For I, BFS reduced D
for W/C=50%, however a significant reduction in D
for W/C=30% was not observed. Using SF enhanced sorption of Cs on HCP, and using BFS slightly improved sorption of Cs on HCP. It was also confirmed that the pore structures of HCP using SF and BFS were connected by fine pores. It was therefore considered that using SF and BFS contributes to the reduction of D
in HCP.
Yoshigoe, Akitaka
Hoshako Riyo No Tebiki, p.130 - 138, 2019/02
The educational book on next-generation synchrotron radiation usage is partially written. This book is being planned by several professors at Tohoku University. In this book, the contents which have already reported in our recent paper [Appl. Phys. Lett. 112 (2018) 021603.] are mainly written. The future perspective on photoemission electron microscopy using next generation synchrotron radiation and its possibility to analyze environmental samples and insulating functional materials are also described.
Sano, Asami; Hattori, Takanori; Komatsu, Kazuki*; Kagi, Hiroyuki*; Nagai, Takaya*; Molaison, J. J.*; Dos Santos, A. M.*; Tulk, C. A.*
Scientific Reports (Internet), 8(1), p.15520_1 - 15520_9, 2018/10
Times Cited Count:56 Percentile:92.66(Multidisciplinary Sciences)The pressure response of hydrogen bond in aluminous hydroxide -AlOOH, which is an important candidate for water carrier to the deep Earth in a subducting slab, was investigated using neutron diffraction under high pressure. The symmetrization of hydrogen bond in which hydrogen locates at the center between two oxygen atoms was observed directly for the first time. The present result indicates that the changes of mineral properties such as increase in bulk modulus and sound velocities, which were previously found, were induced by the symmetrization and disorder state that was also found at just below the symmetrization pressure. Even the symmetrization is a small change in the hydrogen location but it is playing an important role in determining the physical properties of minerals.
Okumura, Masahiko; Kerisit, S.*; Bourg, I. C.*; Lammers, L. N.*; Ikeda, Takashi*; Sassi, M.*; Rosso, K. M.*; Machida, Masahiko
Journal of Environmental Radioactivity, 189, p.135 - 145, 2018/09
Times Cited Count:62 Percentile:87.57(Environmental Sciences)no abstracts in English
Sakai, Toshihiro
JAEA-Data/Code 2018-006, 75 Pages, 2018/07
Data of bulk chemical compositions (major elements and trace elements) and/or of modal compositions of the Toki granitic body are compiled as a data-base for the purpose of improving geological and petrological basic information of the Mizunami Underground Research Laboratory Project and the Regional Hydrogeological Study Project. 696 rock samples are collected from the outcrops and boreholes of the Regional Hydrogeological Study Project, and 636 rock samples are collected from the Mizunami Underground Research Laboratory Construction Site. The analysis data of rock samples, as granitic rock samples, intrusive rock samples and crack filling samples, are attached three-dimensional position information to each thesis and report.
Murakami, Hiroaki; Ashizawa, Masaomi*; Tanaka, Kazuhiro*
Oyo Chishitsu, 59(1), p.2 - 12, 2018/04
This study describes the features of fractures and their fillings along with the long-term behavior of their hydrogeological structures in an underground environment based on the results of a geological investigation conducted at an underground facility in northern Kyushu. Fractures were classified into five groups on the basis of fracture orientation: A, B, C, D, and low-angle groups. The genesis of all fractures is the cooling process of granodiorite pluton. Almost all of the water-conducting fractures are included in the B group. Because a number of fracture fillings in the B group are filled by prehnite and crushed fragments of epidote and quartz, the fractures in this group alternated sealing and re-opening. The fracture characteristics in the B group are follow as: accompanying many alteration halos, long trace length, and cutting off other fractures. These results indicate that fractures in the B group have possibly functioned as pathways for groundwater flow in the long term.