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Koyama, Shinichi; Ikeuchi, Hirotomo; Mitsugi, Takeshi; Maeda, Koji; Sasaki, Shinji; Onishi, Takashi; Tsai, T.-H.; Takano, Masahide; Fukaya, Hiroyuki; Nakamura, Satoshi; et al.
Hairo, Osensui, Shorisui Taisaku Jigyo Jimukyoku Homu Peji (Internet), 216 Pages, 2023/11
In FY 2021 and 2022, JAEA perfomed the subsidy program for "the Project of Decommissioning and Contaminated Water Management (Development of Analysis and Estimation Technology for Characterization of Fuel Debris (Development of Technologies for Enhanced Analysis Accuracy, Thermal Behavior Estimation, and Abbreviated Analysis))" started in FY 2021. This presentation material summarized the results of the project, which will be available shortly on the website of Management Office for the Project of Decommissioning, Contaminated Water and Treated Water Management.
Liu, J.; Dotsuta, Yuma; Kitagaki, Toru; Aoyagi, Noboru; Mei, H.; Takano, Masahide; Kozai, Naofumi
Journal of Nuclear Science and Technology, 60(8), p.1002 - 1012, 2023/08
Times Cited Count：1 Percentile：16.48(Nuclear Science & Technology)Onuki, Toshihiko*; Ye, J.*; Kato, Tomoaki; Liu, J.; Takano, Masahide; Kozai, Naofumi; Utsunomiya, Satoshi*
Environmental Science; Processes & Impacts, 25(7), p.1204 - 1212, 2023/07
Times Cited Count：2 Percentile：15.67(Chemistry, Analytical)To elucidate chemical forms of Cs and I in microparticles produced via the Fukushima Daiichi Nuclear Power Plant accident and released into the atmosphere, we analyzed Cs and I in condensed vaporized particles (CVP) produced by melting experiments using nuclear fuel components containing CsI with concrete. CVPs consisted of many round particles containing Cs and I of diameters less than several tens of micrometers. Two kinds of particles were present: one containing large amounts of Cs and I, suggesting the presence of CsI, and the other containing small amounts of Cs and I with large Si contents. Most of CsI from both particles were dissolved in water. On the contrary, some fractions of Cs remained from the latter particles. These results suggest that Cs was incorporated in CVPs along with Si to form water low-soluble CVPs
/Fe(0) by bacteriaLiu, J.; Dotsuta, Yuma; Kitagaki, Toru; Takano, Masahide; Onuki, Toshihiko; Kozai, Naofumi
Proceedings of International Topical Workshop on Fukushima Decommissioning Research (FDR2022) (Internet), 2 Pages, 2022/10
Nuclear fuel debris, consisting primarily of nuclear fuel and structural material, was formed during the Fukushima Daiichi NPP accident and exists in the cooling water accumulated in the primary containment vessels. Microorganisms living in groundwater may come into contact with the fuel debris and react with it. To assess the degradation of fuel debris, it is necessary to evaluate the interactions between microorganisms and fuel debris. Here we performed an experimental study on bacterial degradation. A mixed powder of UO and Fe(0) was used as a fuel debris simulant. Bacillus subtilis, which is widespread bacteria in nature and thought to be present at the accident site, was used. The mixed powder was exposed to the Bacillus subtilis in a liquid medium for some days. It was found that the oxidative dissolution of the U(IV) and Fe(0) was accelerated by B. subtilis. A fraction of the dissolved U(VI) was precipitated together with iron precipitates which are probably amorphous Fe(III) hydroxides. The study indicates that microorganisms would cause the degradation of fuel debris.
Sakamoto, Kan*; Miura, Yusuke*; Ukai, Shigeharu; Ono, Naoko*; Kimura, Akihiko*; Yamaji, Akifumi*; Kusagaya, Kazuyuki*; Takano, Sho*; Kondo, Takao*; Ikegawa, Tomohiko*; et al.
Journal of Nuclear Materials, 557, p.153276_1 - 153276_11, 2021/12
A FeCrAl-oxide dispersion strengthened (ODS) alloy is a promising candidate alloy for the accident tolerant fuel (ATF) cladding of light water reactors (LWRs) and being developed in Japan recently. This paper will introduce the progress of development of accident tolerant FeCrAl-ODS fuel claddings for boiling water reactors (BWRs) in Japan. Both the experimental and the analytical studies have been performed to evaluate the influence of implementation of the FeCrAl-ODS fuel claddings to the current BWRs. The experimental studies have been conducted to obtain and accumulate key material properties of FeCrAl-ODS fuel claddings by using bar, sheet and tube-shaped materials to support the evaluations in the analytical studies. At the end of paper, the challenges and prospects found in the program are highlighted to enhance international collaborations to accelerate the development of FeCrAl-ODS fuel cladding.
Koyama, Shinichi; Nakagiri, Toshio; Osaka, Masahiko; Yoshida, Hiroyuki; Kurata, Masaki; Ikeuchi, Hirotomo; Maeda, Koji; Sasaki, Shinji; Onishi, Takashi; Takano, Masahide; et al.
Hairo, Osensui Taisaku jigyo jimukyoku Homu Peji (Internet), 144 Pages, 2021/08
JAEA performed the subsidy program for the "Project of Decommissioning and Contaminated Water Management (Development of Analysis and Estimation Technology for Characterization of Fuel Debris (Development of Technologies for Enhanced Analysis Accuracy and Thermal Behavior Estimation of Fuel Debris))" in 2020JFY. This presentation summarized briefly the results of the project, which will be available shortly on the website of Management Office for the Project of Decommissioning and Contaminated Water Management.
Liu, J.; Miyahara, Naoya; Miwa, Shuhei; Takano, Masahide; Hidaka, Akihide; Osaka, Masahiko
Journal of Nuclear Materials, 527, p.151819_1 - 151819_7, 2019/12
Times Cited Count：3 Percentile：23.65(Materials Science, Multidisciplinary)To evaluate the effect of each constituent element on the evaporation rate of ruthenium (Ru) from fission-produced alloy precipitates, the oxidation and evaporation behaviors of metallic Ru, molybdenum (Mo), palladium (Pd), rhodium (Rh) and Mo-Ru-Pd-Rh alloy powders were investigated by thermogravimetric analysis under oxidizing atmospheres from 1473 to 1723 K. The findings led to the following conclusions: (1) The quick oxidation of Mo into condensed Mo oxides can effectively suppress the oxidation and evaporation of Ru in alloy powders; (2) After the complete evaporation of Mo, the evaporation loss rate of Ru would be directly influenced by the Ru activity in the Ru-Pd-Rh alloys, which is determined by the composition of alloys.
Katsuta, Nagayoshi*; Takano, Masao*; Sano, Naomi; Tani, Yukinori*; Ochiai, Shinya*; Naito, Sayuri*; Murakami, Takuma*; Niwa, Masakazu; Kawakami, Shinichi*
Sedimentology, 66(6), p.2490 - 2510, 2019/10
Times Cited Count：9 Percentile：51.94(Geology)Micro-X-ray fluorescence (XRF) scanning spectroscopy of marine and lake sedimentary sequences can provide detailed paleoenvironmental records available through element intensities proxy data. However, problems for effects of interstitial pore water on the micro-XRF intensities have been pointed out so far because of direct measurement on the split wet sediment surfaces. In this study, new methods for the XRF corrections were developed by being considered with the micro-X-ray scanning spectroscopy.
in the liquid nitrogen and natural gas temperature regionsYoshii, Kenji; Hayashi, Naoaki*; Mizumaki, Masaichiro*; Takano, Mikio*
AIP Advances (Internet), 7(4), p.045117_1 - 045117_6, 2017/04
Times Cited Count：10 Percentile：39.01(Nanoscience & Nanotechnology)We have investigated the magnetocaloric effect (MCE) of Ba
Sr
Fe
O (x
0.2), a series of cubic perovskites showing a field-induced transition from helical antiferromagnetism to ferromagnetism. The maximum magnetic entropy change (-
S
) at 50 kOe varies from 
5.8 J kg
K (x=0) to 4.9 J kgK (x=0.2), while the refrigerant capacity remains almost the same at 165 J kg. Interestingly, the temperature of -S decreases from 116 K to 77 K with increasing x, providing this series of rare-earth-free oxides with potential as a magnetic refrigerant for the liquefaction of nitrogen and natural gas.
studied by X-ray spectroscopyMizumaki, Masaichiro*; Fujii, Hitoshi*; Yoshii, Kenji; Hayashi, Naoaki*; Saito, Takashi*; Shimakawa, Yuichi*; Uozumi, Takayuki*; Takano, Mikio*
Physica Status Solidi (C), 12(6), p.818 - 821, 2015/06
Times Cited Count：11 Percentile：94.96(Physics, Condensed Matter)We investigated the electronic structure of BaFeO by using HAXPES and XAS measurements and first principle studies. The experimental and theoretical results indicated that BaFeO is a negative charge transfer compound. We concluded that the on-site Coulomb energy and the strong hybridization between Fe-3d and O-2p orbitals play a very important role of emergence of negative charge transfer. And we found the new structure in the Fe-2p XPS spectrum and concluded this structure is originated from non-local screening.
FeO and zero-thermal expansion compositeNabetani, Koichiro*; Muramatsu, Yuya*; Oka, Kengo*; Nakano, Kiho*; Hojo, Hajime*; Mizumaki, Masaichiro*; Agui, Akane; Higo, Yuji*; Hayashi, Naoaki*; Takano, Mikio*; et al.
Applied Physics Letters, 106(6), p.061912_1 - 061912_5, 2015/02
Times Cited Count：67 Percentile：89.08(Physics, Applied)Negative thermal expansion (NTE) of BiNi
Fe
O
is investigated by dilatometric curves, synchrotron X-ray diffraction, and X-ray absorption spectroscopy. All samples (x=0.05-0.15) shows large NTE with the coefficient of linear thermal expansion which induced by charge transfer between Bi
and Ni
in the controlled temperature range near room temperature. Compared with BiLnNiO (Ln: rare-earth elements), the thermal hysteresis that causes a problem for practical application is suppressed because random distribution of Fe in the Ni site changes the first order transition to second order-like transition.
Washiya, Tadahiro; Yano, Kimihiko; Ikeuchi, Hirotomo; Kaji, Naoya; Takano, Masahide; Morimoto, Kyoichi
Proceedings of 2014 Water Reactor Fuel Performance Meeting/ Top Fuel/ LWR Fuel Performance Meeting (WRFPM 2014) (CD-ROM), 6 Pages, 2014/09
On March 11, 2011, the Great East Japan Earthquake caused the severe accident at Fukushima Daiichi NPS (F1). In the reactors of unit 1-3, large amount of fuel debris was generated. Thermodynamic equilibrium (TDE) calculations based on results of MAAP code analysis was carried out and typical debris phases were predicted. Experimental studies were also carried out using simulated fuel debris, and verify the expected properties. The F1 accident differs from the past severe accidents. Specific factors in the F1 accident to be considered in this study are fuel assembly and control rod materials, core configuration and accident sequence. Further specific factors are high zirconium and iron contents, B
C and sea water effects and molten core concrete interaction (MCCI). Mechanical properties were identified as important properties. Mechanical properties have been obtained experimentally using simulated debris as based on (U,Zr)O
and (U,Zr,Fe)O materials.
Mizumaki, Masaichiro*; Yoshii, Kenji; Hayashi, Naoaki*; Saito, Takashi*; Shimakawa, Yuichi*; Takano, Mikio*
Journal of Applied Physics, 114(7), p.073901_1 - 073901_6, 2013/08
Times Cited Count：23 Percentile：64.81(Physics, Applied)We have investigated the magnetocaloric effect (MCE) of a perovskite oxide, BaFeO, that shows ferromagnetism by the aid of a small external field of about 0.3 T below the Curie temperature T
= 111 K. The magnetization is found to change almost reversibly in both field and temperature cycles. Hence, magnetic and thermal hysteretic losses are negligibly low during refrigeration, a property that is suitable for application. The reversible MCE is likely to arise from the absence of an orbital magnetic moment of Fe ions which are essentially in the Fe
L state (L: ligand hole). The magnetic entropy change and refrigerant capacity near the T are about 5.8 J kg K and about 172 J kg, respectively, both of which are comparable to those of ferromagnetic perovskite manganites. As BaFeO contains no rare metals and is stable against corrosion, the material can be regarded as a candidate refrigerant material.
Takano, Nao*; Takahashi, Yuko*; Yamamoto, Mitsuru*; Teranishi, Mika*; Yamaguchi, Hiroko*; Sakamoto, Ayako; Hase, Yoshihiro; Fujisawa, Hiroko*; Wu, J.*; Matsumoto, Takashi*; et al.
Journal of Radiation Research, 54(4), p.637 - 648, 2013/07
Times Cited Count：15 Percentile：51.17(Biology)Takano, Nao*; Takahashi, Yuko*; Yamamoto, Mitsuru*; Teranishi, Mika*; Hase, Yoshihiro; Sakamoto, Ayako; Tanaka, Atsushi; Hidema, Jun*
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 104, 2012/01
Hayashi, Naoki; Hatakeyama, Shuichiro; Harada, Hiroyuki; Hotchi, Hideaki; Takano, Jumpei*; Tejima, Masaki*; Toyama, Takeshi*
Proceedings of 46th ICFA Advanced Beam Dynamics Workshop on High-Intensity and High-Brightness Hadron Beams (HB 2010) (Internet), p.57 - 61, 2010/09
The Beam Based Alignment (BBA) of the BPM is inevitable for precise and absolute beam position measurements. Even though careful fabrication and installation of the BPM detector, it has to be calibrated by using the beam. Usually, it requires that the individual quadrupole magnet is able to be controlled. However, it is not always that case. In addition, scanning over the all BPM is time consuming procedure. The BBA method under coupled QM environment would help to reduce time for calibration. It presents general formula and experiences at J-PARC RCS and parts of results are compared with the ordinal method at J-PARC MR.
Fujita, Naoki*; Matsui, Toshiyuki*; Kosugi, Shinya*; Sato, Takahiro; Saito, Yuichi; Takano, Katsuyoshi; Koka, Masashi; Kamiya, Tomihiro; Seki, Shu*; Iwase, Akihiro*
Japanese Journal of Applied Physics, 49(6), p.060211_1 - 060211_3, 2010/06
Times Cited Count：12 Percentile：43.92(Physics, Applied)Toyama, Takeshi*; Arakawa, Dai*; Hiramatsu, Shigenori*; Igarashi, Susumu*; Lee, S.*; Matsumoto, Hiroshi*; Odagiri, Junichi*; Tejima, Masaki*; Tobiyama, Makoto*; Hashimoto, Yoshinori*; et al.
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.981 - 983, 2010/05
Experiences of operating BPM's during beam commissioning at the J-PARC MR are reported. The subjects are: (1) bug report, statistics and especially the effect of a beam duct step, (2) position resolution estimation (
30 micrometers with 1 sec averaging), (3) beam based alignment.
Kamiya, Tomihiro; Takano, Katsuyoshi; Ishii, Yasuyuki; Sato, Takahiro; Oikawa, Masakazu*; Okubo, Takeru; Haga, Junji*; Nishikawa, Hiroyuki*; Furuta, Yusuke*; Uchiya, Naoyuki*; et al.
Nuclear Instruments and Methods in Physics Research B, 267(12-13), p.2317 - 2320, 2009/06
Times Cited Count：7 Percentile：45.79(Instruments & Instrumentation)Zukeran, Atsushi*; Chiba, Go; Otsuka, Naohiko*; Ishikawa, Makoto; Takano, Hideki*
JAEA-Research 2008-091, 162 Pages, 2009/02
JAEA-Research-2008-091-01.pdf:5.8MBJAEA-Research-2008-091-02.pdf:45.78MB
Uncertainty of Doppler reactivity is theoretically formulated and then uncertainties of self-shielding factor and its temperature gradient due to errors of resonance parameters were evaluated from NJOY output. Sensitivity analysis was made for 
U, 
U, 
Pu and 
Pu of JENDL-3.3 based on JFS-3 70 group structure. Resultant sensitivity coefficients are provided for the uncertainty evaluation of Doppler reactivity.
