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Matsuya, Yusuke; Yoshii, Yuji*; Kusumoto, Tamon*; Akamatsu, Ken*; Hirata, Yuho; Sato, Tatsuhiko; Kai, Takeshi
Physics in Medicine & Biology, 19 Pages, 2023/00
Times Cited Count：0 Percentile：0.05(Engineering, Biomedical)Time-dependent yields of chemical products resulted in water radiolysis play a great role in evaluating DNA damage response after exposure to ionizing radiation. Particle and Heavy Ion Transport code System (PHITS) is a general-purpose Monte Carlo simulation code for radiation transport, which allows to determine several atomic interactions such as ionizations and electronic excitations as physical stage. However, a chemical code for simulating products of water radiolysis does not exist in the PHITS package. Here, we developed a chemical simulation code dedicated for the PHITS code, hereafter called PHITS-Chem code, which enables calculating G values of water radiolysis species (OH radical, e
, H
, HO etc) by electron beams. The estimated G values during 1 
s are in agreement with the experimental ones and other simulations. This PHITS-Chem code enables simulating the dynamics in the presence of OH radical scavenger, and is useful for evaluating contributions of direct and indirect effects on DNA damage induction. This code will be included and be available in the future version of PHITS.
Yachi, Yoshie*; Kai, Takeshi; Matsuya, Yusuke; Hirata, Yuho; Yoshii, Yuji*; Date, Hiroyuki*
Scientific Reports (Internet), 12, p.16412_1 - 16412_8, 2022/09
Times Cited Count：2 Percentile：47.19(Multidisciplinary Sciences)Recently, magnetic resonance-guided radiotherapy (MRgRT) which can visualize tumors in real time has been developed and installed in several clinical facilities. It is known that Lorentz force modulate macroscopic dose distribution by a charged particle, however, the impact by the force on microscopic radiation-track structure and early DNA damage induction remain unclear. In this study, we simulated the electron-track structure in a static magnetic field using a PHITS, and estimated features of biological effects. We indicated that the macroscopic dose distributions are changed by the force, while early DNA damage such as double strand breaks is attributed to the secondary electrons below a few tens of eV which are independent of the force. We expect that our insight significantly contributes to the MRgRT.
Matsuya, Yusuke; Kai, Takeshi; Sato, Tatsuhiko; Ogawa, Tatsuhiko; Hirata, Yuho; Yoshii, Yuji*; Parisi, A.*; Liamsuwan, T.*
International Journal of Radiation Biology, 98(2), p.148 - 157, 2022/02
Times Cited Count：15 Percentile：80.59(Biology)When investigating radiation-induced biological effects, it is essential to perform detailed track-structure simulations explicitly by considering each atomic interaction in liquid water (which is equivalent to human tissues) at sub-cellular and DNA scales. The Particle and Heavy Ion Transport code System (PHITS) is a Monte Carlo code which can be used for track structure calculations by employing an original electron track-structure mode (etsmode) and the world-famous KURBUC algorithms (PHITS-KURBUC mode) for protons and carbon ions. In this study, the physical features (i.e., range, radial dose and microdosimetry) of these modes have been verified by comparing to the available experimental data and Monte Carlo simulation results reported in literature. In addition, applying the etsmode to radiobiological study, we estimated the yields of single-strand breaks (SSBs), double-strand breaks (DSBs) and complex DSBs, and evaluated the dependencies of DNA damage yields on incident electron energy. As a result, the simulations suggested that DNA damage types are intrinsically related with the spatial patterns of ionization and electronic excitations and that approximately 500 eV electron can cause much complex DSBs. In this paper, we show the development status of the PHITS track-structure modes and its application to radiobiological research, which would be expected to identify the underlying mechanisms of radiation effects based on physics.
Arakawa, Ryoki; Nosaki, Nobuhisa; Hirata, Yuji*
JAEA-Technology 2018-009, 28 Pages, 2019/01
JAEA-Technology-2018-009.pdf:2.94MB
The Naraha Center for Remote Control Technology Development consists of a mock-up test building and a research management building, and various test facilities are installed in them for the decommissioning work after the accident of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings. In the test facilities, the robot test pool for the underwater robot can be tested under temperature conditions raised from room temperature to 60
C. Then, for the purpose of grasping the temperature distribution inside of the pool and the temperature rising behavior in temperature raising condition, a temperature heating test with room temperature to 60C. (maximum setting temperature) was performed, and as well as an analytical study was performed. This report summarizes the obtained both experimental and analytical studies.
Kamiji, Yu; Taniguchi, Masashi*; Nishihata, Yasuo; Nagaishi, Ryuji; Tanaka, Hirohisa*; Hirata, Shingo*; Hara, Mikiya; Hino, Ryutaro
E-Journal of Advanced Maintenance (Internet), 7(1), p.84 - 89, 2015/05
For hydrogen mitigation, a new type passive autocatalytic recombiner is under developing. This new recombiner has been developed from automotive monolithic catalyst in order to reduce weight and to improve hydrogen treating capacity, environmental resistance and product quality. In this study, activation energy of hydrogen-oxygen recombination reaction was examined to clarify the basic characteristics of the catalyst. In addition, the degradation of the catalyst by 
-ray irradiation simulating the environmental condition in nuclear power plants was also examined. As a result, the activation energy was experimentally estimated at 5.75 kJ/mol. Besides, no significant differences were observed in compositional distribution from the EPMA results. On the other hand, specific surface area of the catalyst and surface area of the precious metals were increased. Moreover, catalyst performance test showed that -ray irradiation up to 1.0 MGy can increase activity of catalyst.
Kamiji, Yu; Taniguchi, Masashi*; Nishihata, Yasuo; Nagaishi, Ryuji; Tanaka, Hirohisa*; Hirata, Shingo*; Hara, Mikiya; Hino, Ryutaro
Proceedings of 2nd International Conference on Maintenance Science and Technology (ICMST-Kobe 2014), p.87 - 88, 2014/11
For hydrogen mitigation, a new type passive autocatalytic recombiner is under development. In this study, the activation energy of hydrogen-oxygen recombination reaction was examined to clarify the basic characteristics of the catalyst. In addition, the degradation of the catalyst by -ray irradiation simulating the environmental condition in nuclear power plants was also examined. As a result, the activation energy was experimentally estimated at 5.75 kJ/mol. Besides, no significant differences were observed in the compositional distribution from the EPMA results between the non-irradiated and the irradiated catalyst. However, the irradiated catalyst showed much more activity because of larger specific surface area of the catalyst and surface area of the precious metals. It showed that -ray irradiation up to 1.0 MGy can increase activity of the catalyst.
Sasaki, Yuji; Kitatsuji, Yoshihiro; Hirata, Masaru; Kimura, Takaumi; Yoshizuka, Kazuharu*
Proceedings of International Solvent Extraction Conference "Solvent Extraction-Fundamentals to Industrial Applications" (ISEC 2008), p.745 - 750, 2008/09
The multidentate diamides are synthesized and examined for the actinide (An) extractions, bi- and tridentate extractants are focused in this work. The extraction of actinide was performed from 0.1-6M HNO
to organic solvents. It was obvious that tetraalkyl-diglycolamide (DGA) derivatives, (methylimino)bis(N,N-dioctylacetamide) (MIDOA) and dimethyl-dioctyl-2-(3-oxapentadecane)-malonamide (DMDOOPDMA) have relatively high D values (D(Pu): more than 70). The following notable results using DGA extractants are obtained, (1) DGA with short alkyl chain give higher D values than those with long alkyl chain, (2) DGA with long alkyl chain have high solubility in n-dodecane. The molecular modeling with computational chemistry was also used to elucidate the effects of structural and electronic properties of the reagents on their different extractabilities.
Sasaki, Yuji; Rapold, P.*; Arisaka, Makoto; Hirata, Masaru; Kimura, Takaumi; Hill, C.*; Cote, G.*
Solvent Extraction and Ion Exchange, 25(2), p.187 - 204, 2007/03
Times Cited Count：136 Percentile：92.69(Chemistry, Multidisciplinary)Extraction of Eu(III) and Am(III) from HNO into the organic solvents using N,N,N',N'-tetraoctyl-diglycolamide (TODGA) was investigated in order to study the detailed extraction reaction. The chemical species: 1:2 for metal:TODGA complex is present in polar diluents. On the other hand, the metal complexes need three or more number of TODGA molecules to remain stable in non-polar diluents. The HNO concentration dependence on the distribution ratio suggests that HNO participates in the metal extraction. Infrared spectra indicate that the carbonyl oxygen coordinates with Eu(III), and luminescence lifetimes suggest that there is no water molecule in the inner coordination sphere of Eu-complex extracted.
Shimada, Kenya*; Namatame, Hirofumi*; Taniguchi, Masaki*; Higashiguchi, Mitsuharu*; Fujimori, Shinichi; Saito, Yuji; Fujimori, Atsushi; Kim, M. S.*; Hirata, Daisuke*; Takabatake, Toshiro*
Physica B; Condensed Matter, 378-380, p.791 - 792, 2006/05
Times Cited Count：4 Percentile：22.76(Physics, Condensed Matter)The Ce 4f-derived states in CeRhX (X=Sn and In) were directly examined by means of high-resolution 3d-4f resonance photoemission spectroscopy. Compared with the Kondo metal CePtSn, which has a low Kondo temperature, CeRhX has a strong Ce 4f
weight near the Fermi level (
) and has a weak Ce 4f
peak, indicating a strong valence fluctuation. The Ce 4f spectral features indicate that the c-f hybridization strength in CeRhSn is weaker than that in CeRhIn.
Mn
NHwang, J. I.*; Ishida, Yukiaki*; Kobayashi, Masaki*; Hirata, Gen*; Takubo, Ko*; Mizokawa, Takashi*; Fujimori, Atsushi; Okamoto, Jun; Mamiya, Kazutoshi*; Saito, Yuji; et al.
Physical Review B, 72(8), p.085216_1 - 085216_6, 2005/08
Times Cited Count：64 Percentile：87.86(Materials Science, Multidisciplinary)no abstracts in English
Isozaki, Futoshi*; Kikuchi, Taiji; Ioka, Ikuo; Ishikawa, Kazuyoshi; Hirata, Yuji*
JAERI-Tech 2002-074, 22 Pages, 2002/09
JAERI-Tech-2002-074.pdf:4.98MB
The pressurized tube specimens which enclosed high pressure inert gas were produced for the irradiation creep test. The pressurized tube specimen with 7mm outer diameter and 0.5mm wall thickness must be sealed by the welding, after the helium gas was impressed in the inside of tube. In this process, there was a technical problem of welding under high pressure, and it is difficult to seal the pressurized tube specimen in the present facility of our group. The production process was examined by taking shortening in production period and reduction in the cost into consideration. The sealing technology to enclose the helium gas up to 5.5MPa was established by new technique using the present facility and the mock-up test. And, it is necessary to measure the outer diameter of the pressurized tube specimen with high accuracy in order to predict irradiation creep deformation arising from neutron radiation and internal pressure. Therefore, the method for measuring at the 0.01mm measurement accuracy was established, which combined laser measuring instrument with the lathe.
Takeyama, Tomonori; Chiba, Masaaki; Isozaki, Futoshi*; Amezawa, Hiroo; Itabashi, Yukio; Kikuchi, Taiji; Otabe, Yoshikiyo*; Hirata, Yuji*; Taka, Isamu; Oba, Toshihiro
JAERI-Tech 2001-024, 32 Pages, 2001/03
JAERI-Tech-2001-024.pdf:4.41MB
no abstracts in English
Lee, S.; Kondoh, Takashi; Yoshino, Ryuji; Cho, T.*; Hirata, Mafumi*; Miura, Yukitoshi
Transactions of Fusion Technology, 39(1T), p.151 - 154, 2001/01
no abstracts in English
Enoeda, Mikio; D.F.Holland*; Matsuda, Yuji; Ohira, Shigeru; Okuno, Kenji; *; Hirata, Shingo*
JAERI-Tech 95-050, 90 Pages, 1995/11
no abstracts in English
Hirata, Shingo*; Kakuta, Toshiya*; Ito, H.*; Suzuki, T.*; Hayashi, Takumi; Ishida, Toshikatsu*; Matsuda, Yuji; Okuno, Kenji
Fusion Technology, 28(3), p.1521 - 1526, 1995/10
no abstracts in English
Hayashi, Takumi; Konishi, Satoshi; Ohira, Shigeru; Nakamura, Hirofumi; Inoue, Masahiko*; Watanabe, Tetsuo*; Hirata, Kazuhiro*; Naruse, Yuji; Okuno, Kenji; Barnes, J. W.*; et al.
JAERI-M 93-094, 54 Pages, 1993/03
no abstracts in English
Hayashi, Takumi; Konishi, Satoshi; Nakamura, Hirofumi; Inoue, Masahiko*; Hirata, Kazuhiro*; Okuno, Kenji; Naruse, Yuji; Barnes, J. W.*; W.Harbin*; Anderson, J. L.*; et al.
JAERI-M 93-084, 32 Pages, 1993/03
no abstracts in English
Hayashi, Takumi; Nakamura, Hirofumi; Konishi, Satoshi; Inoue, Masahiko*; Hirata, Kazuhiro*; Okuno, Kenji; Naruse, Yuji; Anderson, J. L.*; Sherman, R. H.*; Willms, R. S.*; et al.
JAERI-M 93-083, 54 Pages, 1993/03
no abstracts in English
Hayashi, Takumi; Nakamura, Hirofumi; Konishi, Satoshi; Inoue, Masahiko*; Hirata, Kazuhiro*; Okuno, Kenji; Naruse, Yuji; Barnes, J. W.*; W.Harbin*; Bartlit, J. R.*; et al.
JAERI-M 93-082, 32 Pages, 1993/03
no abstracts in English
