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Saito, Shigeru; Meigo, Shinichiro; Makimura, Shunsuke*; Hirano, Yukinori*; Tsutsumi, Kazuyoshi*; Maekawa, Fujio
JAEA-Technology 2023-025, 48 Pages, 2024/03
JAEA-Technology-2023-025.pdf:3.11MB
JAEA has been developing Accelerator-Driven Systems (ADS) for research and development of nuclear transmutation using accelerators in order to reduce the volume and hazardousness of high-level radioactive waste generated by nuclear power plants. In order to prepare the material irradiation database necessary for the design of ADS and to study the irradiation effects in Lead-Bismuth Eutectic (LBE) alloys, a proton irradiation facility is under consideration at J-PARC. In this proton irradiation facility, 250 kW proton beams will be injected into the LBE spallation target, and irradiation tests under LBE flow will be performed for candidate structural materials for ADS. Furthermore, semiconductor soft-error tests, medical RI production, and proton beam applications will be performed. Among these, Post Irradiation Examination (PIE) of irradiated samples and RI separation and purification will be carried out in the PIE facility to be constructed near the proton irradiation facility. In this PIE facility, PIE of the equipment and samples irradiated in other facilities in J-PARC will also be performed. This report describes the conceptual study of the PIE facility, including the items to be tested, the test flow, the facilities, the test equipment, etc., and the proposed layout of the facility.
Amekura, Hiroshi*; Chettah, A.*; Narumi, Kazumasa*; Chiba, Atsuya*; Hirano, Yoshimi*; Yamada, Keisuke*; Yamamoto, Shunya*; Leino, A. A.*; Djurabekova, F.*; Nordlund, K.*; et al.
Nature Communications (Internet), 15, p.1786_1 - 1786_10, 2024/02
Injecting high-energy heavy ions in the electronic stopping regime into solids can create cylindrical damage zones called latent ion tracks. Although these tracks form in many materials, none have ever been observed in diamond, even when irradiated with high-energy GeV uranium ions. Here we report the first observation of ion track formation in diamond irradiated with 2-9 MeV C
fullerene ions. Depending on the ion energy, the mean track length (diameter) changed from 17 (3.2) nm to 52 (7.1) nm. High resolution scanning transmission electron microscopy (HR-STEM) indicated the amorphization in the tracks, in which 
-bonding signal from graphite was detected by the electron energy loss spectroscopy (EELS).
Hirano, Tatsumi*; Maeda, Takehiro*; Murata, Tetsuyuki*; Yamamoto, Takahiro*; Matsubara, Eiichiro*; Shobu, Takahisa; Shiro, Ayumi*; Yasuda, Ryo*; Takamatsu, Daiko*
SPring-8/SACLA Riyo Kenkyu Seikashu (Internet), 11(5), p.345 - 353, 2023/10
no abstracts in English
Shibanuma, Tomohiro; Hirano, Hiroshi*; Kimura, Yasuhisa; Aita, Takahiro; Yoshida, Masato; Nagai, Yuya; Kitamura, Akihiro
Hoken Butsuri (Internet), 58(2), p.91 - 98, 2023/08
We developed new containment tents that are more easily assembled and effectively functioned, by improving and refurbishing the shortcomings of the conventional tents. The new tents have been already tested in the real airborne contamination situation occurred at the plutonium fuel fabricating facility. The tents appropriately functioned for intended use but other shortcomings emerged and therefore we had modified the structure of the tents further.
Nagai, Yuya; Shuji, Yoshiyuki; Kawasaki, Takeshi; Aita, Takahiro; Kimura, Yasuhisa; Nemoto, Yasunori*; Onuma, Takeshi*; Tomiyama, Noboru*; Hirano, Koji*; Usui, Yasuhiro*; et al.
JAEA-Technology 2022-039, 117 Pages, 2023/06
JAEA-Technology-2022-039.pdf:11.96MB
Japan Atomic Energy Agency (JAEA) manages wide range of nuclear facilities. Many of these facilities are required to be performed adjustment with the aging and complement with the new regulatory standards and the earthquake resistant, since the Great East Japan Earthquake and the Fukushima Daiichi Nuclear Power Station accident. It is therefore desirable to promote decommissioning of facilities that have reached the end of their productive life in order to reduce risk and maintenance costs. However, the progress of facility decommissioning require large amount of money and radioactive waste storage space. In order to address these issues, JAEA has formulated a "The Medium/Long-Term Management Plan of JAEA Facilities" with three pillars: (1) consolidation and prioritization of facilities, (2) assurance of facility safety, and (3) back-end countermeasures. In this plan, Plutonium Fuel Fabrication Facility has been selected as primary decommissioned facility, and dismantling of equipment in the facilities have been underway. In this report, size reduction activities of the glove box W-9 and a part of tunnel F-1, which was connected to W-9, are presented, and the obtained findings are highlighted. The glovebox W-9 had oxidation & reduction furnace, and pellet crushing machine as equipment interior. The duration of activity took six years from February 2014 to February 2020, including suspended period of 4 years due to the enhanced authorization approval process
Onodera, Naoyuki; Idomura, Yasuhiro; Hasegawa, Yuta; Asahi, Yuichi; Inagaki, Atsushi*; Shimose, Kenichi*; Hirano, Kohin*
Keisan Kogaku Koenkai Rombunshu (CD-ROM), 28, 4 Pages, 2023/05
We have developed a multi-scale wind simulation code named CityLBM that can resolve entire cities to detailed streets. CityLBM enables a real time ensemble simulation for several km square area by applying the locally mesh-refined lattice Boltzmann method on GPU supercomputers. On the other hand, real-world wind simulations contain complex boundary conditions that cannot be modeled, so data assimilation techniques are needed to reflect observed data in the simulation. This study proposes an optimization method for ground surface temperature bias based on an ensemble Kalman filter to reproduce wind conditions within urban city blocks. As a verification of CityLBM, an Observing System Simulation Experiment (OSSE) is conducted for the central Tokyo area to estimate boundary conditions from observed near-surface temperature values.
Hirano, Tatsumi*; Maeda, Takehiro*; Murata, Tetsuyuki*; Yamaki, Takahiro*; Matsubara, Eiichiro*; Shobu, Takahisa; Shiro, Ayumi*; Yasuda, Ryo*; Takamatsu, Daiko*
SPring-8/SACLA Riyo Kenkyu Seikashu (Internet), 11(1), p.49 - 57, 2023/02
Asakawa, Jun; Hirano, Hiroshi*; Nagai, Yuya; Aita, Takahiro; Shibanuma, Tomohiro; Kimura, Yasuhisa
Hoken Butsuri (Internet), 57(2), p.93 - 101, 2022/09
In the dismantling work of glove boxes (GBs) contaminated with radioactive materials at the nuclear fuel facilities, plastic tents are constructed around the entire GBs, and workers putting on air-fed suits (AFS) (hereinafter referred to as AFS worker) dismantle the GBs and interior equipment by using cutting tools. If an AFS worker suddenly feels sick during the work and the worker is unable to move independently, it will be necessary to exit in the shortest time from the viewpoint of respecting human life. In this case, a lot of radioactive materials may be brought into the contamination control room, thus the room and the equipment of the workers may be contaminated. Consequently, until the decontamination work is completed, the other AFS workers will have to put on AFS and wait for long time, which puts a strain on the workers. In this report, the plastic enclosure tents for body decontamination developed in JAEA were used as a new contamination control room replaced the contaminated one, and the procedure to quickly exit the remaining AFS workers was proposed. As a result, we confirmed that it was possible to greatly reduce the waiting time of the other AFS workers who is forced to wait in the dismantling area.
strain induces severe corrosion by retrieving electrons from Fe
under a freshwater environmentHirano, Shinichi*; Ihara, Sota*; Wakai, Satoshi*; Dotsuta, Yuma; Otani, Kyohei; Kitagaki, Toru; Ueno, Fumiyoshi; Okamoto, Akihiro*
Microorganisms (Internet), 10(2), p.270_1 - 270_12, 2022/02
Times Cited Count：7 Percentile：84.82(Microbiology)To understand the role of methanogens in corrosion under anoxic conditions in freshwater, we investigated the corrosion activities of methanogens in samples collected from groundwater and rivers. We enriched microorganisms that can grow with CO
/NaHCO
and Fe as the sole carbon source and electron donor, respectively, in ground fresh water. Electrochemical analysis revealed that strain can uptake electrons from the cathode at lower than -0.61 V vs SHE and has a redox-active component with electrochemical potential different from those of other previously reported methanogens with extracellular electron transfer ability. This study indicated the corrosion risk by methanogens capable of taking up electrons from Fe in anoxic freshwater environments and the necessity of understanding the corrosion mechanism to contribute to risk diagnosis.
Oda, Chie; Kawama, Daisuke*; Shimizu, Hiroyuki*; Benbow, S. J.*; Hirano, Fumio; Takayama, Yusuke; Takase, Hiroyasu*; Mihara, Morihiro; Honda, Akira
Journal of Advanced Concrete Technology, 19(10), p.1075 - 1087, 2021/10
Times Cited Count：0 Percentile：0(Construction & Building Technology)Concrete in a transuranic (TRU) waste repository is considered a suitable material to ensure safety, provide structural integrity and retard radionuclide migration after the waste containers fail. In the current study, coupling between chemical, mass-transport and mechanical, so-called non-linear processes that control concrete degradation and crack development were investigated by coupled numerical models. Application of such coupled numerical models allows identification of the dominant non-linear processes that will control long-term concrete degradation and crack development in a TRU waste repository.
Amekura, Hiroshi*; Toulemonde, M.*; Narumi, Kazumasa*; Li, R.*; Chiba, Atsuya*; Hirano, Yoshimi*; Yamada, Keisuke*; Yamamoto, Shunya*; Ishikawa, Norito; Okubo, Nariaki; et al.
Scientific Reports (Internet), 11(1), p.185_1 - 185_11, 2021/01
Times Cited Count：12 Percentile：75.03(Multidisciplinary Sciences)We report the track formation of 10 nm in diameter in silicon irradiated with 6 MeV C, i.e., much lower energy than the previously reported energy threshold.
Benbow, S. J.*; Kawama, Daisuke*; Takase, Hiroyasu*; Shimizu, Hiroyuki*; Oda, Chie; Hirano, Fumio; Takayama, Yusuke; Mihara, Morihiro; Honda, Akira
Crystals (Internet), 10(9), p.767_1 - 767_33, 2020/09
Times Cited Count：2 Percentile：26.57(Crystallography)Details are presented of the development of a coupled modeling simulator for assessing the evolution in the near-field of a geological repository for radioactive waste disposal where concrete is used as a backfill. The simulator uses OpenMI, a standard for exchanging data between simulation software programs at run-time, to form a coupled chemical-mechanical-hydrogeological model of the system. The approach combines a tunnel scale stress analysis finite element model, a discrete element model for accurately modeling the patterns of emerging cracks in the concrete, and a finite element and finite volume model of the chemical processes and alteration in the porous matrix and cracks in the concrete, to produce a fully coupled model of the system. Combining existing detailed simulation software in this way with OpenMI has the benefit of not relying on simplifications that might be necessary to combine all of the modeled processes in a single piece of software.
Takamizawa, Hisashi; Nishiyama, Yutaka; Hirano, Takashi*
Proceedings of ASME 2020 Pressure Vessels and Piping Conference (PVP 2020) (Internet), 7 Pages, 2020/08
no abstracts in English
and 200 MeV Xe ion irradiationLi, R.*; Narumi, Kazumasa*; Chiba, Atsuya*; Hirano, Yu*; Tsuya, Daiju*; Yamamoto, Shunya*; Saito, Yuichi*; Okubo, Nariaki; Ishikawa, Norito; Pang, C.*; et al.
Nanotechnology, 31(26), p.265606_1 - 265606_9, 2020/06
Times Cited Count：5 Percentile：33.01(Nanoscience & Nanotechnology)We report the elongation of embedded Au nanoparticles (NPs) in three different matrices under irradiations of 4 MeV C ions and 200 MeV Xe ions. Large elongation of Au NPs was observed for crystalline indium tin oxide (ITO) under both 4 MeV C and 200 MeV Xe irradiation. The ITO layer preserved the crystallinity even after large elongation was induced. This is the first report of the elongation of metal NPs in a crystalline matrix.
Kondo, Yasuhiro; Hirano, Koichiro; Ito, Takashi; Kikuzawa, Nobuhiro; Kitamura, Ryo; Morishita, Takatoshi; Oguri, Hidetomo; Okoshi, Kiyonori; Shinozaki, Shinichi; Shinto, Katsuhiro; et al.
Journal of Physics; Conference Series, 1350, p.012077_1 - 012077_7, 2019/12
Times Cited Count：1 Percentile：52.28(Physics, Particles & Fields)We have upgraded a 3-MeV linac at J-PARC. The ion source is same as the J-PARC linac's, and the old 30-mA RFQ is replaced by a spare 50-mA RFQ, therefore, the beam energy is 3 MeV and the nominal beam current is 50 mA. The main purpose of this system is to test the spare RFQ, but also used for testing of various components required in order to keep the stable operation of the J-PARC accelerator. The accelerator has been already commissioned, and measurement programs have been started. In this paper, present status of this 3-MeV linac is presented.
Saito, Yoshimoto*; Hirano, Shinichi*; Nagaoka, Toru*; Amano, Yuki
Ecological Genetics and Genomics, 12, p.100042_1 - 100042_9, 2019/10
Culture-independent molecular techniques enable us to analyze microflora in various environments. Many uncultured prokaryotes have been detected by the molecular methods from extreme environments, including anaerobic, no light, high-pressure, and high temperature. Recently, microbial eukaryotes were also detected in deep-sea environments, suggesting that microbial eukaryotes can adapt to a wider range of environments than previously thought. Here, we performed a culture-independent analysis of eukaryotes from approximately -250 m depth in the Horonobe Underground Research Laboratory at Horonobe, Japan. Our results indicate that fungi are the dominant eukaryotic flora in deep sedimentary rocks of Horonobe. We detected a wide range of species, including Zygomycete, Basidiomycete, and Ascomycete fungi from the rocks. This study is the first report of eukaryotic diversity in deep subsurface sedimentary rocks.
Mihara, Morihiro; Hirano, Fumio; Takayama, Yusuke; Kyokawa, Hiroyuki*; Ono, Shintaro*
Genshiryoku Bakkuendo Kenkyu (CD-ROM), 24(1), p.15 - 25, 2017/06
A computer program MACBECE has been developed to provide rigorous calculations of the long-term mechanical behavior of a TRU waste geological repository. Consideration is given to the expected chemical alteration of repository components, including cementitious materials and bentonite, and the mechanical interactions between repository and host rock. The long-term mechanical behavior of a TRU waste repository was evaluated in a deep soft rock site, where creep deformation is likely to occur from the initial construction phase to 10
years after repository closure. It was found that the stress didn't fall into a singularity of yield surface of the EC model applied to the mechanical behavior model of bentonite. The calculated displacement of the inner diameter of the repository, considering mechanical interaction between repository and host rock, was about half that of a result in 2nd progress report on R&D for TRU waste disposal in Japan.
Kondo, Yasuhiro; Asano, Hiroyuki*; Chishiro, Etsuji; Hirano, Koichiro; Ishiyama, Tatsuya; Ito, Takashi; Kawane, Yusuke; Kikuzawa, Nobuhiro; Meigo, Shinichiro; Miura, Akihiko; et al.
Proceedings of 28th International Linear Accelerator Conference (LINAC 2016) (Internet), p.298 - 300, 2017/05
We have constructed a linac for development of various accelerator components at J-PARC. The ion source is same as the J-PARC linac's, and the RFQ is a used one in the J-PARC linac. The beam energy is 3 MeV and nominal beam current is 30 mA. The accelerator has been already commissioned, and the first development program, laser-charge-exchange experiment for the transmutation experimental facility, has been started. In this paper, present status of this 3-MeV linac is presented.
Sawabe, Yuki*; Ishiyama, Tatsuya; Takahashi, Daisuke; Kato, Yuko; Suzuki, Takahiro*; Hirano, Koichiro; Takei, Hayanori; Meigo, Shinichiro; Kikuzawa, Nobuhiro; Hayashi, Naoki
Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.647 - 651, 2016/11
In the J-PARC, a 3 MeV linac has been developed for the tests of beam scraper irradiation and charge exchange by high-power laser. To accomplish tests efficiently and safely, the control system for 3 MeV was designed and developed, and this system consists of four subsystems, personal protection system, machine protection system, timing system, and remote control system using the EPICS. In this paper, the details of control system for a 3 MeV linac are presented.
Hirano, Koichiro; Asano, Hiroyuki; Ishiyama, Tatsuya; Ito, Takashi; Okoshi, Kiyonori; Oguri, Hidetomo; Kondo, Yasuhiro; Kawane, Yusuke; Kikuzawa, Nobuhiro; Sato, Yoshikatsu; et al.
Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.310 - 313, 2016/11
We have used a beam scraper with the incident angle of 65deg to reduce the beam power deposition density in the MEBT between a 324 MHz RFQ and a 50-MeV DTL of the J-PARC linac. The 65
scraper was irradiated by the H
beam up to particle number of 1.47E22. We observed a lot of surface projections with several hundred micrometers high in the beam irradiation damage on the scraper by using the laser microscope. In order to study the limits of scrapers, we constructed a new 3 MeV linac at J-PARC. We will conduct the scraper irradiation test at the end of this year.
