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Saito, Yuki*; Ishiwata, Tobimaru*; Horiuchi, Misato*; Nishiki, Yuto*; Kikuchi, Ryosuke*; Otake, Tsubasa*; Kawakita, Ryohei; Takayama, Yusuke; Mitsui, Seiichiro; Sato, Tsutomu*
2024 Nendo Shigen, Sozai Gakkai Shunki Taikai Koenshu, 7 Pages, 2024/03
no abstracts in English
Nagai, Takayuki; Okamoto, Yoshihiro; Yamagishi, Hirona*; Shibata, Daisuke*; Kojima, Kazuo*; Hasegawa, Takehiko*; Sato, Seiichi*; Fukaya, Akane*; Hatakeyama, Kiyoshi*
JAEA-Research 2023-004, 45 Pages, 2023/09
JAEA-Research-2023-004.pdf:6.07MB
The local structure of glass-forming elements and waste elements in borosilicate glasses varies with its chemical composition. In this study, simulated waste glass samples were prepared and the chemical state regarding boron (B), silicon (Si) and waste elements of iron (Fe), cesium (Cs) were estimated by using XAFS measurement in soft X-ray region. To understand the chemical stability of simulated waste glasses, XANES spectra of B K-edge, Fe L
, L
-edge, and Cs M
, M
-edge were measured on the glass surface exposed to the leachate. As a result, it was found that the glass surface exposed to the leachate was changed and it was difficult to obtain a clear XANES spectrum. From the B K-edge XANES spectra on glass surfaces exposed to the leachate, an increase in three-coordination of B-O (BO) and a decrease in four-coordination of B-O (BO) were observed compared to the glass surfaces before immersion. The XANES spectra of Fe L, L-edge, and Cs M, M-edge show that as the exposure time in the leachate increases, the Cs present on the glass surface dissolves into the leachate. The XANES spectra of Si K-edge were measured on simulated waste glass surfaces before immersion, and it was confirmed that the change in XANES spectra given by NaO concentration had a larger effect than the waste component concentration.
Okamoto, Yoshihiro; Shiwaku, Hideaki; Shimamura, Keisuke*; Kobayashi, Hidekazu; Nagai, Takayuki; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*
Journal of Nuclear Materials, 570, p.153962_1 - 153962_13, 2022/11
Simulated nuclear waste glass samples containing phosphorus, which increase the solubility of molybdenum, were prepared and analyzed using synchrotron X-ray Absorption Fine Structure (XAFS) analysis for some constituent elements and Raman spectroscopic analysis of their complex structure. Changes in local structure and chemical state due to different phosphorus additions and waste loading rates were systematically studied. Consequently, no crystalline phase due to the molybdate compound was observed even at a maximum waste content of 30 wt% (corresponding to 1.87 mol% MoO
). Oxidation proceeded when the waste-loading rate was increased, whereas the reduction proceeded when phosphorus was added. In some cases, the effects of oxidation and reduction were offset. The local structure around specific elements can be classified as follows; Zn that is affected mainly by the waste-loading rate, Ce that is affected by both the waste-loading rate and phosphorus addition, and Zr element that is not affected by either of them. From the comparison between the analytical results of Mo and other elements, it was considered that the added phosphorus exists as a free PO
structural unit and may deprive the alkali metal coordinated to the molybdate ion.
Nagai, Takayuki; Okamoto, Yoshihiro; Yamagishi, Hirona*; Kojima, Kazuo*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*
JAEA-Research 2022-008, 37 Pages, 2022/10
JAEA-Research-2022-008.pdf:5.27MB
The local structure of glass-forming elements and waste elements in borosilicate glasses varies with its chemical composition. In this study, borosilicate glass frit and simulated waste glass samples were prepared and the chemical state regarding boron (B), silicon (Si) and waste elements of iron (Fe), cesium (Cs) were estimated by using XAFS measurement in soft X-ray region. Following results were obtained by XAFS measurements of simulated waste glass surfaces after immersion test to investigate the long chemical stability. (1) As the leaching time of glass samples in immersion test passed, the Cs M, M-edge XANES spectra disappeared and the Fe L, L-edge spectra changed. (2) A new compound was formed on the sample surface after the immersion test, and these changes in the surface state were confirmed by Raman spectroscopy. However, it became difficult to obtain a clear B K-edge XANES spectrum by forming a compound on glass surfaces. The Si K-edge XANES spectra of borosilicate glass frits with different NaO content were measured, and following was confirmed. (1) As the NaO concentration increases in borosilicate glass frit, the K-edge peak of Si shifts to the low energy side. (2) The intensity of the Si K-edge peak is maximum when the NaO content in glass frits was about 7wt%.
Nagai, Takayuki; Okamoto, Yoshihiro; Yamagishi, Hirona*; Ota, Toshiaki*; Kojima, Kazuo*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*
JAEA-Research 2021-010, 62 Pages, 2022/01
JAEA-Research-2021-010.pdf:6.05MB
The local structure of glass-forming elements and waste elements in borosilicate glasses varies with its chemical composition. In this study, borosilicate glass frit and simulated waste glass samples were prepared and the local structure and chemical state regarding boron(B), oxygen(O), silicon(Si) and waste elements of iron(Fe), cesium(Cs) were estimated by using XAFS measurement in soft X-ray region. Following results were obtained by XAFS measurements of prepared glass frit and simulated waste glass samples: (1) The effect of NaO concentration on B-O coordination structure is greater than that of the waste elements concentration. (2) The height of pre-edge by O K-edge spectrum depends on the concentration of first transition elements such as Fe in glass samples. Following results were obtained by XAFS measurements of simulated waste glass samples after immersion test to investigate the long chemical stability. (1) A new compound was formed on the sample surface after the immersion test, and changes in the surface state were confirmed by Raman spectroscopy. (2) Cs on the sample surface after immersion test dissolves into the leaching solution. The Si K-edge XANES spectra of borosilicate glass frits and simulated waste glass samples included lanthanides oxide were measured, and following was confirmed. (1) As the NaO concentration increases in borosilicate glass frit, the K-edge peak of Si shifts to the low energy side. (2) The peak height of the K-edge of Si differs depending on the kind of lanthanide.
Nagai, Takayuki; Okamoto, Yoshihiro; Yamagishi, Hirona*; Ota, Toshiaki*; Kojima, Kazuo*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*
JAEA-Research 2020-009, 48 Pages, 2020/09
JAEA-Research-2020-009.pdf:4.53MB
The local structure of glass-forming elements and waste elements in waste glass varies with its chemical composition. In this study, borosilicate glass frit and simulated waste glass samples were prepared and the local structure and chemical state regarding boron (B), oxygen (O), and waste elements of cerium (Ce), cesium (Cs) were estimated by using XAFS measurement in soft X-ray region. Following results were obtained by XAFS measurements of prepared glass frit and simulated waste glass samples: (1) The existence ratio of four coordinate sp
structure (BO) tends to increase with increasing NaO content in glass samples. (2) The height of a pre-edge which appears by K-edge XANES spectrum of O is so high that the Fe content in glass samples. Following results were obtained by XAFS measurements of simulated waste glass samples after immersion test to investigate long chemical stability. (1) The existence ratio of four coordinate sp structure (BO) increases by immersion test. (2) Ce which exists in the surface layer is oxidized by immersion test, and much of Cs in surface layer is lost after leach testing. Even if the glass frit form (fiber cartridge or beads) and manufacturing method were changed and a glass sample of the similar chemical composition was prepared, these observed Raman spectra of samples were different.
Nagai, Takayuki; Sasage, Kenichi; Okamoto, Yoshihiro; Shiwaku, Hideaki; Yamagishi, Hirona*; Ota, Toshiaki*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*; Takahashi, Tomoe*; et al.
JAEA-Research 2019-003, 94 Pages, 2019/09
JAEA-Research-2019-003.pdf:7.92MB
The local structures of glass-forming elements and waste elements would change by the chemical composition of waste glass including those elements. In this study, simulated waste glass samples were prepared from borosilicate glass frit including phosphorus (P) or vanadium (V), and we investigated local structures of boron, sodium, and waste elements in these P glass and V glass samples by using synchrotron XAFS measurements in soft and hard X ray region.
Nagai, Takayuki; Okamoto, Yoshihiro; Shiwaku, Hideaki; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*; Hirono, Kazuya*; Homma, Masanobu*; Kobayashi, Hiromi*; Takahashi, Tomoe*; et al.
JAEA-Research 2018-007, 87 Pages, 2018/11
JAEA-Research-2018-007.pdf:61.21MB
To select the chemical composition of a glass frit which can increase the waste content, the simulated waste glass samples prepared from a borosilicate glass frit including vanadium (V) were investigated by using Laser Ablation (LA) ICP-AES analysis, Raman spectrometry, and synchrotron XAFS measurement in this study on foundation business of the Agency for Natural Resources and Energy.
Okamoto, Yoshihiro; Nagai, Takayuki; Shiwaku, Hideaki; Inose, Takehiko*; Sato, Seiichi*
Nihon Genshiryoku Gakkai Wabun Rombunshi, 16(4), p.180 - 190, 2017/12
X-ray absorption fine structure (XAFS) and imaging XAFS analyses were performed to elucidate chemical state of rhodium in the simulated waste glass. The chemical forms of Rh in the glass were evaluated to be 84% RhO and 16% metal/alloy as the result of linear combination analysis of EXAFS data. According to the imaging XAFS analysis, the chemical form of Rh which was located together with Ru was mainly oxide (RhO). It suggests that stable (Ru,Rh)O solid solution exists in the simulated glass. On the other hand, that of Rh of which distribution did not accord with Ru in the glass was mainly metallic. In the case of metallic Rh in the glass, it tended to become an aggregation form. It can be concluded that the chemical state of Rh was much affected by the existence and distribution of Ru element.
Kamei, Gento; Honda, Akira; Oda, Chie; Hirano, Fumio; Ichige, Satoru; Kurimoto, Yoshitaka; Hoshino, Seiichi; Akagi, Yosuke; Sato, Nobuyuki; Takahashi, Kuniaki; et al.
JAEA-Research 2012-010, 80 Pages, 2012/06
JAEA-Research-2012-010.pdf:7.45MB
Based on Japanese governmental policy and general scheme, research and development of geological disposal technology for TRU waste has been proceeding to improve reliability of the safety assessment of the co-locational disposal of TRU waste and of HLW, to expand the basement of generic safety assessment, and to develop the alternative technology to cope with the broad geologic environment of Japan. Japan Atomic Energy Agency is dealing with the assignments in the governmental generic scheme. We report here the progress of the studies at the end of H22 (2010) Japanese fiscal year and their products during the last 5 years. These include (1) evaluation of long-term mechanical stability in the near-field including development of a creep mode of rock and analyses of mechanical behavior of TRU waste repository, (2) performance assessment of the disposal system including cementitious material alteration, bentonite and hostrock alteration with alkaline solution and nitrate effect, and (3) alternative technology development including decomposition of nitrate.
Tatebe, Kazuaki; Suzuki, Yurina; Shirato, Seiichi; Sato, Yoshinori
JAEA-Data/Code 2011-024, 84 Pages, 2012/02
JAEA-Data-Code-2011-024.pdf:2.87MB
The recent society requires business activities with environmental consideration to every enterprise. Also, Japanese laws require those activities. For example, "Environmental Consideration Law" mandates publication of a report relating to the activities of environmental consideration to each enterprise over a certain size. "Act on the Rational Use of Energy" mandates the report of the results of energy consumption and the long-term plan of the rational use of energy. Moreover, "Act on Promotion of Global Warming Countermeasures" mandates the report of the greenhouse gas emissions. In addition to those, "Water Pollution Control Law" and other environmental laws as well as environmental ordinances require business activities with environmental consideration to all companies. So, it is very important for JAEA to report business activities with environmental consideration in order to build up trustful relations with the people and communities. The Environmental Data Management System has been developed as the data base of business activities with environmental consideration at JAEA and the means to promote the activities at every site and office of JAEA. This report summarizes the structure of the environmental data management system, kinds of environmental performance data treated by the system, and gathering methods of the data.
Kamei, Gento; Honda, Akira; Mihara, Morihiro; Oda, Chie; Ichige, Satoru; Kurimoto, Yoshitaka; Hoshino, Seiichi; Akagi, Yosuke; Sato, Nobuyuki; Murakami, Hiroshi*; et al.
JAEA-Research 2011-002, 82 Pages, 2011/03
JAEA-Research-2011-002.pdf:5.64MB
Based on Japanese governmental policy and general scheme, research and development of geological disposal technology for TRU waste has been proceeding to improve reliability of the safety assessment of the co-locational disposal of TRU waste and of HLW, to expand the basement of generic safety assessment, and to develop the alternative technology to cope with the broad geologic environment of Japan. Japan Atomic Energy Agency is dealing with the assignments in the governmental generic scheme. We report here the progress of the studies at the end of H20 (2008) Japanese fiscal year, which are (1) evaluation of long-term mechanical stability in the near-field including development of a creep mode of rock and analyses of mechanical behavior of TRU waste repository, (2) performance assessment of the disposal system including data acquisition and preparation on radionuclides migration, cementitious material alteration, bentonite and hostrock alteration with alkaline solution and nitrate effect, and (3) alternative technology development including decomposition of nitrate.
irradiationFujisato, Toshiya*; Kikuchi, Masahiro; Sakashita, Tetsuya; Funayama, Tomoo; Kobayashi, Yasuhiko; Funamoto, Seiichi*; Kimura, Tsuyoshi*; Kishida, Akio*; Yamaoka, Tetsuji*
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 119, 2008/03
Synthetic materials, such as ePTFE or Dacron are not suitable for reconstructing the small-diameter arteries. In contrast, tissue engineering (TE) graft has been attracting great attention recently. One of the promising approaches of TE grafts is using acellular tissues. The acellular scaffold may have the same structure and characteristics as the natural tissue and can be replaced with the host tissues. In this study, we prepared the acellular scaffold using irradiation, which is expected to induce the apoptosis of the cells.
Kikuchi, Masahiro; Gunawardane, C. R.; Alam, M. K.; Mohd Dzomir, A. Z.; Pitipanaarachchi, R. C.; Funayama, Tomoo; Hamada, Nobuyuki*; Sakashita, Tetsuya; Wada, Seiichi*; Sato, Katsuya; et al.
Radioisotopes, 56(9), p.509 - 517, 2007/09
Since ionizing radiation is used for sterilizing or lowering the microbial content of foods, the development of versatile detection methods of irradiated foods is necessary for appropriate management. In an effort to distinguish between irradiated and non-irradiated food, a method based on the detection of oxidative DNA base damage using the chemiluminescence enzyme-linked immunosorbent assay (ELISA) with anti-8-hydroxy-2'-deoxyguanosine antibody was developed. It was shown that this chemiluminescence ELISA method could be applied to chicken, beef and pork that were irradiated with over 3 kGy. Twenty milligrams of a loaf of meat was sufficient to distinguish between irradiated and non-irradiated meat by this method.
Seki, Shuhei*; Tsukuda, Satoshi*; Tagawa, Seiichi*; Sugimoto, Masaki; Sato, Takahiro; Oikawa, Masakazu*; Sakai, Takuro
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 145, 2007/02
no abstracts in English
PprA proteinSato, Katsuya*; Wada, Seiichi; Kikuchi, Masahiro; Funayama, Tomoo; Narumi, Issei; Kobayashi, Yasuhiko
Mutation Research; Fundamental and Molecular Mechanisms of Mutagenesis, 596(1-2), p.36 - 42, 2006/04
Times Cited Count：4 Percentile：10.91(Biotechnology & Applied Microbiology)In a previous study we identified the novel protein PprA that plays a critical role in the radiation resistance of . In this study, we focussed on the ability of PprA protein to recognize and bind to double-stranded DNA carrying strand breaks, and attempted to visualize radiation-induced DNA strand breaks in mammalian cultured cells by employing PprA protein using an immunofluorescence technique. Increased PprA protein binding to CHO-K1 nuclei immediately following irradiation suggests the protein is binding to DNA strand breaks. By altering the cell permeabilization conditions, PprA protein binding to CHO-K1 mitochondria, which is probably resulted from DNA strand break immediately following irradiation, was also detected. The method developed and detailed in this study will be useful in evaluating DNA damage responses in cultured cells, and could also be applicable to genotoxic tests in the environmental and pharmaceutical fields.
Moritani, Kosuke; Okada, Michio*; Sato, Seiichi*; Goto, Seishiro*; Kasai, Toshio*; Yoshigoe, Akitaka; Teraoka, Yuden
Journal of Vacuum Science and Technology A, 22(4), p.1625 - 1630, 2004/08
Times Cited Count：25 Percentile：66.06(Materials Science, Coatings & Films)We studied the oxidation of Cu{111} surface with a hyperthermal O molecular beam (HOMB) using X-ray photoemission spectroscopy (XPS) in conjunction with a synchrotron radiation (SR) source. The efficiency of oxidation with 0.6-eV-HOMB is higher thab that with 2.3-eV-HOMB under 
0.5ML. Ont the other hand, further oxidation occurs rather inefficiency under 
0.5ML. In this region, efficiency of oxidation with 2.3-eV-HOMB is higher than 0.6-eV-HOMB. We found that such slow oxidation process of Cu can be interpreted in terms of a collision-induced-adsorption mechanism. These results suggest that we can control the oxidation process of Cu by using HOMB.
Tamai, Hiroshi; Matsukawa, Makoto; Kurita, Genichi; Hayashi, Nobuhiko; Urata, Kazuhiro*; Miura, Yushi; Kizu, Kaname; Tsuchiya, Katsuhiko; Morioka, Atsuhiko; Kudo, Yusuke; et al.
Plasma Science and Technology, 6(1), p.2141 - 2150, 2004/02
Times Cited Count：2 Percentile：6.49(Physics, Fluids & Plasmas)The dominant issue for the the modification program of JT-60 (JT-60SC) is to demonstrate the steady state reactor relevant plasma operation. Physics design on plasma parameters, operation scenarios, and the plasma control method are investigated for the achievement of high-
. Engineering design and the R&D on the superconducting magnet coils, radiation shield, and vacuum vessel are performed. Recent progress in such physics and technology developments is presented.
Ishida, Shinichi; Abe, Katsunori*; Ando, Akira*; Chujo, T.*; Fujii, Tsuneyuki; Fujita, Takaaki; Goto, Seiichi*; Hanada, Kazuaki*; Hatayama, Akiyoshi*; Hino, Tomoaki*; et al.
Nuclear Fusion, 43(7), p.606 - 613, 2003/07
no abstracts in English
Ishida, Shinichi; Abe, Katsunori*; Ando, Akira*; Cho, T.*; Fujii, Tsuneyuki; Fujita, Takaaki; Goto, Seiichi*; Hanada, Kazuaki*; Hatayama, Akiyoshi*; Hino, Tomoaki*; et al.
Nuclear Fusion, 43(7), p.606 - 613, 2003/07
Times Cited Count：33 Percentile：69.14(Physics, Fluids & Plasmas)no abstracts in English
