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observation of radiation-induced defects in ZrN under electron irradiation in HVEMRahman, M. M.*; Yamamoto, Tomokazu*; Matsumura, Sho*; Takaki, Seiya; Takano, Masahide; Costantini, J. M.*; Yasuda, Kazuhiro*
Nuclear Instruments and Methods in Physics Research B, 549, p.165289_1 - 165289_8, 2024/04
Nucleation-and-growth process of radiation-induced defects in zirconium nitride (ZrN) has been investigated 
under electron irradiation by using a high voltage transmission electron microscope (HVEM) under electron irradiation by using a high voltage transmission electron microscope (HVEM).
Hayashi, Koichi*; Lederer, M.*; Fukumoto, Yohei*; Goto, Masashi*; Yamamoto, Yuta*; Happo, Naohisa*; Harada, Masahide; Inamura, Yasuhiro; Oikawa, Kenichi; Oyama, Kenji*; et al.
Applied Physics Letters, 120(13), p.132101_1 - 132101_6, 2022/03
Times Cited Count：5 Percentile：36.96(Physics, Applied)Sakai, Kenji; Oku, Takayuki; Okudaira, Takuya; Kai, Tetsuya; Harada, Masahide; Hiroi, Kosuke; Hayashida, Hirotoshi*; Kakurai, Kazuhisa*; Shimizu, Hirohiko*; Hirota, Katsuya*; et al.
JPS Conference Proceedings (Internet), 33, p.011116_1 - 011116_6, 2021/03
In neutron fundamental physics, study of correlation term 
of a neutron spin 
and a target nuclear spin 
is important because term interferes to parity non-conserving (PNC) and time reversal non-conserving terms. For this study, a xenon (Xe) is an interesting nucleus because it has been observed an enhancement of PNC effect around neutron resonance peaks, and polarizes up to 
by using a spin exchange optical pumping (SEOP) method. We would plan to develop a polarized Xe gas target with a compact in-situ SEOP system, and to study term by utilizing epithermal neutron beams supplied from a high intense pulsed spallation neutron source. As the first step, we attempted to measure neutron polarizing ability caused by term at a 9.6 eV s-wave resonance peak of 
Xe at BL10 in MLF, by detecting change 
of ratio between neutron transmissions with the polarized and unpolarized Xe target. After demonstrating that our apparatus could detect small change (
) of neutron transmissions caused by Doppler broadening effect, a signified value of has been obtained as preliminary results. For analyzing the obtained in detail, we are improving our nuclear magnetic resonance and electron paramagnetic resonance systems for evaluating Xe polarization independently of neutron beams.
Li, Y.; Hirota, Takatoshi*; Itabashi, Yu*; Yamamoto, Masato*; Kanto, Yasuhiro*; Suzuki, Masahide*; Miyamoto, Yuhei*
JAEA-Review 2020-011, 130 Pages, 2020/09
JAEA-Review-2020-011.pdf:9.31MB
For the improvement of the structural integrity assessment methodology on reactor pressure vessels (RPVs), the probabilistic fracture mechanics (PFM) analysis code PASCAL has been developed and improved in Japan Atomic Energy Agency based on the latest knowledge. The PASCAL code evaluates the failure probabilities and frequencies of Japanese RPVs under transient events such as pressure thermal shock considering neutron irradiation embrittlement. In order to confirm the reliability of the PASCAL as a domestic standard code and to promote the application of PFM on the domestic structural integrity assessments of RPVs, it is important to perform verification activities, and summarize the verification processes and results as a document. On the basis of these backgrounds, we established a working group, composed of experts on this field besides the developers, on the verification of the PASCAL module and the source program of PASCAL was released to the members of working group. This report summarizes the activities of the working group on the verification of PASCAL in FY2016 and FY2017.
Iguchi, Masahide; Morimoto, Masaaki; Chida, Yutaka*; Hemmi, Tsutomu; Nakajima, Hideo; Nakahira, Masataka; Koizumi, Norikiyo; Yamamoto, Akio*; Miyake, Takashi*; Sawa, Naoki*
IEEE Transactions on Applied Superconductivity, 24(3), p.3801004_1 - 3801004_4, 2014/06
Times Cited Count：7 Percentile：37.57(Engineering, Electrical & Electronic)no abstracts in English
Kubo, Junichi*; Rahman, N.*; Takahashi, Nobuaki; Kawai, Takahiko*; Matsuba, Go*; Nishida, Koji*; Kanaya, Toshiji*; Yamamoto, Masahide*
Journal of Applied Polymer Science, 112(3), p.1647 - 1652, 2009/05
Times Cited Count：27 Percentile：63.52(Polymer Science)Aiming at improvement of mechanical and dielectric properties of poly(vinyl alcohol) (PVA) we prepared composites of PVA and magnesium nitrate. It was found that the composites were very soft and rubber-like, and the glass transition temperature decreased with increasing the salt concentration. Wide-angle X-ray diffraction and small-angle X-ray scattering revealed that the crystallites of PVA were destroyed by the additive and it was a cause of the softening.
Shima, Shigeki*; Gasa, Shinichi*; Amano, Hikaru; Nagao, Seiya*; Yamamoto, Masayoshi*; Momoshima, Noriyuki*; Furukawa, Masahide*; Kimura, Hideki*; Kawamura, Hisao*
JAEA-Conf 2008-003, p.28 - 31, 2008/04
Concentrations of I in surface seawater around Japan were approximately 2
10
atoms/L in literatures. However, the atomic ratio of iodine to cesium was ten times as high as that of the global fallout. The origin of I in the water columns seems to be difficult to be explained by only the global fallout. Discharge from European plants was one of the possible origins of iodine from the standpoint of air mass trajectory analysis. Concentration of I in rain water was 10 times higher than that in surface seawater. Anthropogenic inorganic iodine in surface seawater predominantly dissolves as an iodide ion (I
).
Matsuda, Masahide*; Yamamoto, Tetsuya*; Nakai, Kei*; Endo, Kiyoshi*; Kumada, Hiroaki; Kageji, Teruyoshi*; Matsumura, Akira*
Proceedings of 12th International Congress on Neutron Capture Therapy (ICNCT-12), p.40 - 42, 2006/10
To describe the failure patterns and survival seen with high-grade glioma treated with BNCT, the dose distribution and the clinical responses were retrospectively analyzed. BSH-based BNCT was performed in 12 patients with high-grade glioma (grade IV 7, grade III 5). The post-diagnosis median survival time of 12 patients was 19.8 months (range 3.3-47.2). Four cases of local control, 3 of local recurrence, 3 of distant intraparenchymal recurrence and 2 of subarachnoid dissemination were recorded. According to the analysis of the failure patterns, minimum GTV dose of 26 GyEq or more is necessary for local control.
Yamai, Hideki*; Konishi, Satoshi; Hara, Masahide*; Okuno, Kenji; Yamamoto, Ichiro*
Fusion Technology, 28(3), p.1591 - 1596, 1995/10
no abstracts in English
Sakai, Kenji; Oku, Takayuki; Okudaira, Takuya; Kai, Tetsuya; Harada, Masahide; Hiroi, Kosuke; Hayashida, Hirotoshi*; Shimizu, Hirohiko*; Yamamoto, Tomoki*; Ino, Takashi*; et al.
no journal, ,
In neutron fundamental physics, a study of correlation term of a neutron spin s and a target nuclear spin is important because the term interferes to parity non-conserving (PNC) and time reversal non-conserving (TRNC) terms. For this study, a xenon (Xe) is an interesting nucleus because it has been observed an enhancement of PNC effect around neutron resonance peaks, and polarizes up to 
by using a spin exchange optical pumping (SEOP) method. We attempted to develop a polarized Xe target in a compact SEOP system and measure neutron polarizing ability caused by the term at a 9.6 eV 
-wave resonance peak of Xe, by detecting change 
of a ratio between neutron transmissions with the polarized and unpolarized Xe target. As preliminary results, we observed a signified value of 
after demonstrating that our apparatus could distinguish Doppler broadening effect as systematic error.
Sakai, Kenji; Oku, Takayuki; Harada, Masahide; Kai, Tetsuya; Hiroi, Kosuke; Hayashida, Hirotoshi*; Kira, Hiroshi*; Shimizu, Hirohiko*; Hirota, Katsuya*; Okudaira, Takuya*; et al.
no journal, ,
no abstracts in English
Yamamoto, Kazuyoshi; Xu, P. G.; Oikawa, Kenichi; Harada, Masahide; Inamura, Yasuhiro; Nakamura, Mitsutaka; Kodama, Katsuaki
no journal, ,
TOF neutron diffractometers typically use 
t
(time between neutron detection and target collision) as flight time. However, this is inaccurate due to moderator thermalization time after initial neutron slowing. We developed a patent-filed correction method to obtain a more accurate flight time. This involves pre-calculating the moderator's time response using neutron transport calculations and subtracting a delay time from t for each event. We validated this using data from J-PARC MLF-BL10 (NOBORU) and Rietveld analysis. Results show the correction reduces the coefficient of the quadratic term in the calibration equation (as determined by Rietveld analysis), improving linearity. Originally designed for small-scale sources, this method can be applied to larger facilities, contributing to the overall accuracy of TOF neutron diffraction, and this correction allows for more accurate measurements.
