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Yokota, Akira; Seya, Manato; Sugawara, Satoshi; Ishikawa, Joji; Yokobori, Tomohiko
JAEA-Technology 2026-010, 73 Pages, 2026/07
The Advanced Volume Reduction Facilities (AVRF) were constructed to produce waste packages compatible with future near-surface disposal. The facilities primarily target low-level beta/gamma solid waste generated from the Nuclear Science Research Institute and other research facilities. The processing operations at the AVRF include dismantling, sorting, repackaging, supercompaction, melting and other treatments. Since operations commenced in 1999, approximately 10,000 units (equivalent to 200-liter drums) of waste have been processed as of the end of FY2018. The conduct of treatment operations and the stable operation of AVRF require proper maintenance and management of the Electricity and Machinery Unit, which include power distribution unit, air compressor unit, exhaust unit, gas supply units, drainage units, and other electromechanical units. Since these units were first put into operation, they have been appropriately maintained and operated, including routine inspections and repairs. Compiling the operational and maintenance records of the Electricity and Machinery Unit to date is considered important for ongoing operations. This paper reports on the operational and maintenance status of the Electricity and Machinery Unit.
Iketani, Shotaro; Suzuki, Takeshi; Yokobori, Tomohiko; Sugawara, Satoshi; Yokota, Akira; Kikuchi, Genta; Muraguchi, Yoshinori; Kitahara, Masaru; Seya, Manato; Kurosawa, Tsuyoshi; et al.
JAEA-Technology 2025-001, 169 Pages, 2025/08
The radioactive waste treatment facilities at the Nuclear Science Research Institute includes the Radioactive Waste Treatment Facility No. 3, Waste Size Reduction and Storage Facility, and Waste Volume Reduction Facility. These three facilities come under the purview of the Act on the Regulation of Nuclear Source Material, Nuclear Fuel Material and Reactors, and are included under Class C of the act based on the seismic requirements specified in the Act. We assessed the seismic capacity of these three radioactive waste treatment facilities based on the current Building Standards Act, to verify whether they comply with the new regulatory requirements enforced by the Nuclear Regulation Authority (NRA) in the aftermath of the 2011 nuclear accident at the Fukushima Daiichi Nuclear Power Station operated by the Tokyo Electric Power Company. We found that the allowable stress of a few structural members used in the construction of the facilities did not meet the regulatory requirements. After studying the approval granted by the NRA for the construction plans, including the design and construction methods (design and construction plans) of the three facilities on March 5, 2021, we made aseismic reinforcement at these facilities between 2021 and 2022. This report presents an overview of the seismic design of these facilities and an outline of the aseismic reinforcement conducted, management system existing, safety measures adopted, and the preoperational inspections conducted at these facilities.
Sugawara, Takanori; Kunieda, Satoshi
Proceedings of International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2023) (Internet), 7 Pages, 2023/08
This study investigates the impact of the change from JENDL-4 to JENDL-5 on neutronics analysis of transmutation systems. As the transmutation systems, the following two systems are targeted: JAEA-ADS, a lead-bismuth cooled accelerator-driven system, and MARDS, a molten salt chloride accelerator-driven system. For the JAEA-ADS, the k-eff value increased 189 pcm from JENDL-4 to JENDL-5. It was found that the revisions of various nuclides affected to this difference. For example, the revision of
N indicated an increase of 200 pcm from the JENDL-4 result. For the MARDS, it was found that the major revision of
Cl and
Cl cross sections was the main cause of the k-eff differences. This study confirmed that the difference in the nuclear data libraries still indicated differences in calculation results for the transmutation systems.
Sugawara, Takanori; Kita, Satoshi*; Yoshimoto, Hidemitsu*; Okubo, Nariaki
JAEA-Technology 2018-008, 26 Pages, 2018/09
The oxygen sensors to measure the oxygen concentration in liquid LBE (lead-bismuth eutectic) were fabricated and tested for future use in LBE-cooled ADS (accelerator-driven system) or LBE test loops. The following tests were performed; estimation of catalyst application range, freeze seal structure and estimation of gamma-ray irradiation effect. For the estimation of the catalyst application range, it was confirmed that the measurement accuracy became worse in low LBE temperature as the application range became small. For the freeze seal structure, we realized the structure to prevent the LBE leakage with 0.5 MPa pressure condition. For the estimation of gamma-ray irradiation effect, the ex-situ test was carried out and it was observed that there was little effect by 4 MGy gamma-ray irradiation.
Ru
)
Sb
investigated by inelastic X-ray scatteringTsutsui, Satoshi; Kaneko, Koji; Miyazaki, Ryoichi*; Higashinaka, Ryuji*; Aoki, Yuji*; Kobayashi, Riki*; Wakimoto, Shuichi; Baron, A. Q. R.*; Sugawara, Hitoshi*; Sato, Hideyuki*
JPS Conference Proceedings (Internet), 3, p.011060_1 - 011060_5, 2014/06
Yamasaki, Chisato*; Murakami, Katsuhiko*; Fujii, Yasuyuki*; Sato, Yoshiharu*; Harada, Erimi*; Takeda, Junichi*; Taniya, Takayuki*; Sakate, Ryuichi*; Kikugawa, Shingo*; Shimada, Makoto*; et al.
Nucleic Acids Research, 36(Database), p.D793 - D799, 2008/01
Times Cited Count:53 Percentile:69.99(Biochemistry & Molecular Biology)Here we report the new features and improvements in our latest release of the H-Invitational Database, a comprehensive annotation resource for human genes and transcripts. H-InvDB, originally developed as an integrated database of the human transcriptome based on extensive annotation of large sets of fulllength cDNA (FLcDNA) clones, now provides annotation for 120 558 human mRNAs extracted from the International Nucleotide Sequence Databases (INSD), in addition to 54 978 human FLcDNAs, in the latest release H-InvDB. We mapped those human transcripts onto the human genome sequences (NCBI build 36.1) and determined 34 699 human gene clusters, which could define 34 057 protein-coding and 642 non-protein-coding loci; 858 transcribed loci overlapped with predicted pseudogenes.
P
Ishii, Kenji; Tsutsui, Satoshi*; Hao, L.*; Hasegawa, Tomoo*; Iwasa, Kazuaki*; Tsubota, Masami; Inami, Toshiya; Murakami, Yoichi*; Saha, S. R.*; Sugawara, Hitoshi*; et al.
Journal of Magnetism and Magnetic Materials, 310(2, Part1), p.e178 - e180, 2007/03
PrRu
P
shows a metal-insulator (MI) transition at
62 K accompanied by a structural phase transition. Because LaRu
P
without
electrons does not shows the MI transition,
electrons in the Pr atom plays an important role in the transition. In order to elucidate a modulation of electronic states of Pr, we have carried out a resonant X-ray scattering study of PrRu
P
at Pr
- and
-edges. Below
, resonant signal at the absorption main-edge was successfully observed at the superlattice reflections of the modulation vector
in addition to the energy-independent component from the lattice distortion. Because the reflection contains the difference of anomalous scattering factors between two Pr atoms in the unit cell, two different electronic states are actually ordered below
. Furthermore we found that the polarization of X-ray is mostly unrotated even at the resonance, which indicates that the resonant scattering in PrRu
P
is almost isotropic.
4P
Kawana, Daichi*; Kuwahara, Keitaro*; Sato, Masashi*; Takagi, Masatoshi*; Aoki, Yuji*; Kogi, Masafumi*; Sato, Hideyuki*; Sagayama, Hajime*; Osakabe, Toyotaka; Iwasa, Kazuaki*; et al.
Journal of the Physical Society of Japan, 75(11), p.113602_1 - 113602_4, 2006/11
Times Cited Count:11 Percentile:55.08(Physics, Multidisciplinary)We report the first X-ray diffraction experiments of PrFe
P
under high pressure. We discovered a symmetry lowering from cubic to orthorhombic or lower at the metal-insulator transition temperature, accompanied by a jump in the lattice constant, which indicates a first-order phase transition. The superlattice reflections at q=(1,0,0) observed in the low-pressure nonmagnetic ordered phase are found to disappear in the insulating phase. The temperature dependence of the lattice constant and the absence of the superlattice reflections are well explained by taking into account an antiferromagnetic ordering.
Sugawara, Toru*; Endo, Satoshi*; Ishii, Yoshikazu*; Morimoto, Kyoichi
no journal, ,
Calorimetry for nuclear fuel materials at high temperature is essential to evaluate irradiation behavior, heat transfer and phase equilibria of fuel pellets. In the cases of metallurgical and ceramic engineering, the important temperature range is below about 1800 K. On the other hand, fuel center temperature is over 2000 K in an operating nuclear reactor, and heat capacity of UO
shows comprehensive temperature dependence at high temperature such as anomalous increase at about 1900 K or more and Bredig transition at 2670 K. Experimental techniques of calorimetry for high temperature samples are reviewed and a calorimeter for nuclear fuel materials that we developed is described.
Sasa, Toshinobu; Saito, Shigeru; Obayashi, Hironari; Wan, T.; Sugawara, Takanori; Kita, Satoshi*; Yamaki, Kenichi*; Yoshimoto, Hidemitsu*
no journal, ,
JAEA proposes the Partitioning and Transmutation Technology to reduce the environmental impact caused from high-level radioactive waste using Accelerator-driven system (ADS) which adopts lead-bismuth eutectic alloy (LBE) as a coolant for subcritical core and spallation target. To realize ADS, JAEA plans to construct the Transmutation Experimental Facility (TEF) within the framework of J-PARC project. By using TEF in J-PARC, it is planned to solve technical issues for safe application of LBE by completing the data to design LBE-cooled ADS. The 250kW LBE spallation target will be located in TEF facility to prepare material irradiation database by both proton and neutron injection in the temperature range for typical LBE-cooled ADS. Detailed design and optimization of the target as a reference target of TEF-T and various elemental technologies are investigated. The large scale LBE loops for mock up the spallation target and material corrosion studies are also manufactured and ready for various experiments. The latest status of 250kW LBE spallation target design works will be described in the presentation.
Kumakura, Satoshi*; Sugita, Yutaka; Sanada, Hiroyuki; Nakamura, Takahiro; Obara, Yuichi*; Sugawara, Takayuki*; Fujii, Yoshiaki*
no journal, ,
no abstracts in English
Maekawa, Fujio; Sasa, Toshinobu; Takei, Hayanori; Saito, Shigeru; Obayashi, Hironari; Yamaguchi, Kazushi; Wan, T.; Tsujimoto, Kazufumi; Nishihara, Kenji; Sugawara, Takanori; et al.
no journal, ,
As one of experimental facilities of J-PARC (Japan Proton Accelerator Research Complex), we have a plan to construct the Transmutation Experimental Facility (TEF). TEF consists of two facilities: the ADS Target Test Facility (TEF-T) and the Transmutation Physics Experimental Facility (TEF-P). TEF-T equips a liquid lead-bismuth spallation target bombarded by a 400 MeV - 250 kW proton beam in which candidate proton beam window materials are to be irradiated. TEF-P equips a critical/subcritical assembly to investigate physical and dynamic properties of the accelerator-driven system by using a low power (10W) proton beam. Uranium, Plutonium and minor actinide fuels are planned to be loaded into the assembly. Recent progress in R&D efforts toward construction of J-PARC TEF will be presented.
Sugawara, Takanori; Kunieda, Satoshi
no journal, ,
no abstracts in English
Abe, Takumi; Iwamoto, Hiroki; Obayashi, Hironari; Sugawara, Takanori; Kureta, Masatoshi
no journal, ,
no abstracts in English
Sugawara, Takanori; Abe, Takumi; Iwamoto, Hiroki; Obayashi, Hironari; Kureta, Masatoshi
no journal, ,
no abstracts in English
P
Ishii, Kenji; Tsubota, Masami; Inami, Toshiya; Tsutsui, Satoshi*; Hao, L.*; Hasegawa, Tomoo*; Iwasa, Kazuaki*; Murakami, Yoichi; Sugawara, Hitoshi*; Saha, S. R.*; et al.
no journal, ,
PrRu
P
shows a metal-insulator (MI) transition at
62 K accompanied by a structural phase transition. Because LaRu
P
without
electrons does not shows the MI transition,
electrons in the Pr atom plays an important role in the transition. In order to elucidate a modulation of electronic states of Pr, we have carried out a resonant X-ray scattering study of PrRu
P
at Pr
- and
-edges. Below
, resonant signal at the absorption main-edge was successfully observed at the superlattice reflections of the modulation vector
in addition to the energy-independent component from the lattice distortion. Because the reflection contains the difference of anomalous scattering factors between two Pr atoms in the unit cell, two different electronic states are actually ordered below
. Furthermore we found that the polarization of X-ray is mostly unrotated even at the resonance, which indicates that the resonant scattering in PrRu
P
is almost isotropic.
Nishitani, Takeo; Okada, Koichi; Sato, Satoshi; Sasao, Mamiko*; Iwasaki, Tomohiko*; Sugawara, Takanori; Shinto, Katsuhiro*; Kitajima, Sumio*; Nomura, Ken*
no journal, ,
no abstracts in English