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Nakanishi, Chika*; Ota, Masakazu; Hirouchi, Jun; Takahara, Shogo
JAEA-Research 2023-012, 29 Pages, 2024/02
The OSCAAR program is a probabilistic risk assessment program for reactor accidents developed by Japan Atomic Energy Agency. To improve the model included in the OSCAAR program, which is about long-term exposure caused by the resuspension of radioactive materials deposited on soil surfaces, we calculated resuspension factors for Cs-137. The one- dimensional atmosphere-SOiL-VEGetation model, SOLVEG-R was utilized to compute resuspension factor. The wind velocity was kept constant in this study since it significantly affects particle resuspension behavior. Our calculations indicate that wind velocities below 6 m s resulted in little variation in the annual mean resuspension factor at a height of 1 m. However, as wind velocities increased above 6 m s
, the resuspension factor significantly increased. The resuspension factors ranged from 10
to 10
m
for wind velocities ranging from 1 m s
to 7 m s
.
Kawamura, Seiko; Nakajima, Kenji; Inamura, Yasuhiro; Tsujimoto, Yoshihiro*; Kitada, Atsushi*; Takeiri, Fumitaka*; Kageyama, Hiroshi*; Ajiro, Yoshitami*; Nishi, Masakazu*; Kakurai, Kazuhisa
Journal of Physics; Conference Series, 320, p.012037_1 - 012037_5, 2011/09
Times Cited Count:0 Percentile:0.00(Physics, Condensed Matter)The magnetic ground state of (CuCl)LaNbO
has been suggested to be a spin-singlet state with an excitation gap of
meV, while (CuCl)LaTa
O
has an antiferromagnetic (AFM) ground state. The systems are suspected to be a frustrated quantum spin system due to the competition between the nearest and next-nearest exchange interactions. We have studied magnetic excitation in these systems by ToF inelastic neutron scattering technique. The measurements were performed on powder samples of (CuCl)LaNb
O
and (CuCl)LaTa
O
at a disk-chopper-type spectrometer AMATERAS in J-PARC. In both systems, a band-like excitation was observed at
meV. The
dependence of the intensity of magnetic excitation around 2 meV for (CuCl)LaNb
O
well reproduces that observed at a triple-axis spectrometer, exhibiting characteristics of spin-singlet dimers. On the other hand, (CuCl)LaTa
O
in the AFM state exhibits a different
dependence.
Ishiwata, Shintaro*; Okuyama, Daisuke*; Kakurai, Kazuhisa; Nishi, Masakazu*; Taguchi, Yasujiro*; Tokura, Yoshinori*
Physical Review B, 81(17), p.174418_1 - 174418_8, 2010/05
Times Cited Count:81 Percentile:91.52(Materials Science, Multidisciplinary)Takenoshita, Yoshihisa*; Tojima, Futoshi*; Nishi, Hiroyuki*; Shirao, Tsukasa*; Nagatani, Takeshi*; Oe, Masakazu*; Hase, Yoshihiro; Narumi, Issei
JAEA-Review 2008-055, JAEA Takasaki Annual Report 2007, P. 66, 2008/11
no abstracts in English
Uehara, Shinichi*; Kobayashi, Akira*; Chijimatsu, Masakazu*; Onishi, Yuzo*; Fujita, Tomoo; Rejeb, A.*
Proceedings of 3rd International Conference on Coupled T-H-M-C Processes in Geo-systems; Fundamentals, Modeling, Experiments and Applications (GeoProc 2008), p.419 - 425, 2008/06
Uehara, Shinichi*; Kobayashi, Akira*; Chijimatsu, Masakazu*; Onishi, Yuzo*; Fujita, Tomoo
Proceedings of 2nd International Conference on Coupled T-H-M-C Processes in Geo-systems; Fundamentals, Modeling, Experiments and Applications (GeoProc 2006), p.738 - 743, 2006/05
This paper reports the results of calculations about coupled hydro-mechanical process in the domain around excavations at clay rock site at Tournemire, France. We operated the numerical modelling by using a Finite Element Method code named THAMES, on the assumption that swelling pressure is parallel to saturation ratio. The results of modelling indicated that saturation ratio changes seasonally at the domain within several tens cm from tunnel wall. This extension is similar to that of damage zone observed in the tunnel at Tournemire site in 1881, which supports the idea that the saturation-desaturation cycles has decreased the rock strength and caused damage zone extension. The modelling results also suggested that the consideration of swelling pressure could affect evolution of stress state abruptly.
Kanaya, Toshiji*; Kakurai, Kazuhisa; Tsukushi, Itaru*; Inoue, Rintaro*; Watanabe, Hiroshi*; Nishi, Masakazu*; Nakajima, Kenji; Takemura, Kazuhiro*; Furuya, Hidemine*
Journal of the Physical Society of Japan, 74(12), p.3236 - 3240, 2005/12
Times Cited Count:6 Percentile:41.24(Physics, Multidisciplinary)We performed thermal neutron spin echo measurements on a glass-forming polymer, deuterated polybutadiene (-[CD-CD=CD-CD
]
-; PB-d
), in a high
range up to 3.5
covering the first and second peaks of the structure factor S(
), and evaluated the decay rate
(
) of the coherent intermediate scattering function as a function of
. In contrast to the previous experimental findings on the first peak of S(
) at
= 1.5
, no "de Gennes" type narrowing was observed on the second peak at
= 2.9
. This novel finding indicates that the narrowing is hidden by the distinct motions of the soft -CD
-CD
- and =CD-CD
- units and the self-motions of the rigid and soft units in the
range around the second peak.
Kakurai, Kazuhisa; Nukui, Katsuyuki*; Aso, Naofumi*; Nishi, Masakazu*; Kadowaki, Hiroaki*; Kageyama, Hiroshi*; Ueda, Yutaka*; Regnault, L.-P.*; Cpas, O.*
Progress of Theoretical Physics Supplement, (159), p.22 - 32, 2005/10
no abstracts in English
Aso, Naofumi*; Kageyama, Hiroshi*; Nukui, Katsuyuki*; Nishi, Masakazu*; Kadowaki, Hiroaki*; Ueda, Yutaka*; Kakurai, Kazuhisa
Journal of the Physical Society of Japan, 74(8), p.2189 - 2192, 2005/08
Times Cited Count:8 Percentile:47.86(Physics, Multidisciplinary)no abstracts in English
Nishitani, Tomohiro; Nakanishi, Tsutomu*; Yamamoto, Masahiro*; Okumi, Shoji*; Furuta, Fumio*; Miyamoto, Masaharu*; Kuwahara, Makoto*; Yamamoto, Naoto*; Naniwa, Kenichi*; Watanabe, Osamu*; et al.
Journal of Applied Physics, 97(9), p.094907_1 - 094907_6, 2005/05
Times Cited Count:66 Percentile:87.45(Physics, Applied)no abstracts in English
Sugita, Yutaka; Chijimatsu, Masakazu*; Ito, Akira; Kurikami, Hiroshi; Kobayashi, Akira*; Onishi, Yuzo*
P.102-107, p.102 - 107, 2003/00
None
Kurikami, Hiroshi; Kobayashi, Akira*; Chijimatsu, Masakazu*; Sugita, Yutaka; Onishi, Yuzo*
Proceedings of International Conference on Coupled T-H-M-C Processes in Geo-systems; Fundamentals, Modelling, Experiments and Applications (GeoProc 2003), p.403 - 408, 2003/00
It is very important in performance assessment to estimate the impact of constructing high-level radioactive waste repositories deep underground on the regional groundwater flow system. This paper proposes a method of estimating the impact of coupled t
Saito, Masahiro*; Okada, Noriko*; Nishibori, Eiji*; Takagiwa, Hiroyuki*; Yokoo, Tetsuya*; Nishi, Masakazu*; Kakurai, Kazuhisa; Kunii, Satoru*; Takata, Masaki*; Sakata, Makoto*; et al.
Journal of the Physical Society of Japan, 71(10), p.2369 - 2372, 2002/10
Times Cited Count:14 Percentile:61.83(Physics, Multidisciplinary)no abstracts in English
Kato, Mineo; Ito, Takeshi*; Sugai, Hiroyuki; Kawamura, Yoshinori; Hayashi, Takumi; Nishi, Masataka; Tanase, Masakazu; Matsuzaki, Teiichiro*; Ishida, Katsuhiko*; Nagamine, Kanetada*
Fusion Science and Technology, 41(3), p.859 - 862, 2002/05
JAERI has a plane to develop a compact tritium gas recycling system for fusion research. This system is also very attractive for the muon-catalyzed fusion (CF) research at RIKEN-RAL Muon Facility in UK. For the research, JAERI has produced high purity tritium gas of 1,500 Ci and transported it to the Facility. In the
CF experiments, the tritium gas was diluted by the deuterium in an optional concentration and the used tritium gas was carried back by the tritium transport container developed to JAERI. If it is possible to recycle the diluted tritium gas, i.e., the used tritium gas is enriched in the experimental site, the
CF experiments should be conducted efficiently. rom the above point of view, in this paper, we propose the compact tritium gas recycling system based on the gas chromatography that has already developed in JAERI and a proton conductor.
Niitaka, Seiji*; Yoshimura, Kazuyoshi*; Kosuge, K.*; Nishi, Masakazu*; Kakurai, Kazuhisa
Physical Review Letters, 87(17), p.177202_1 - 177202_4, 2001/10
Times Cited Count:99 Percentile:91.54(Physics, Multidisciplinary)no abstracts in English
Cpas, O.*; Kakurai, Kazuhisa; Regnault, L. P.*; Ziman, T.*; Boucher, J. P.*; Aso, Naofumi*; Nishi, Masakazu*; Kageyama, Hiroshi*; Ueda, Yutaka*
Physical Review Letters, 87(16), p.167205_1 - 167205_4, 2001/10
Times Cited Count:108 Percentile:92.30(Physics, Multidisciplinary)no abstracts in English
Sugita, Yutaka; Nguyen, T. S.*; Brgesson, L.*; Chijimatsu, Masakazu*; Rutqvist, J.*; Fujita, Tomoo; Hernelind, J.*; Kobayashi, Akira*; Onishi, Yuzo*; Tanaka, Makoto*; et al.
International Journal of Rock Mechanics and Mining Sciences, 38(1), p.79 - 94, 2001/00
None
Nakamura, Hiroyuki*; Yamasaki, Tomoaki*; Giri, S.*; Imai, Hideto*; Shiga, Masayuki*; Kojima, Kenji*; Nishi, Masakazu*; Kakurai, Kazuhisa*; Metoki, Naoto
Journal of the Physical Society of Japan, 69(9), p.2763 - 2766, 2000/09
Times Cited Count:61 Percentile:86.78(Physics, Multidisciplinary)no abstracts in English
Kawarazaki, Shuzo*; Sato, Masugu*; Miyako, Yoshihito*; Chigusa, Nobusato*; Watanabe, Kenji*; Metoki, Naoto; Koike, Yoshihiro; Nishi, Masakazu*
Physical Review B, 61(6), p.4167 - 4173, 2000/02
Times Cited Count:86 Percentile:93.50(Materials Science, Multidisciplinary)no abstracts in English
Chijimatsu, Masakazu*; Fujita, Tomoo; Kobayashi, Akira*; Onishi, Yuzo*
JNC TN8400 99-031, 61 Pages, 1999/06
It is an important part of the near field performance assessment of nuclear waste disposal to evaluate couples thermo-hydro-mechanical (T-H-M) phenomena, e.g., thermal effects on groundwater flow through rock matrix and water seepage into the buffer material, the generation of swelling pressure of the buffer material, and thermal stresses potentially affecting porosity and fracture apertures of the rock. An in-situ T-H-M experiment naned 'Engineered Barrier Experiment' has been oonducted at the Kamaishi Mine, of which host rock is granodiorite, in order to establish conceptual models of the coupled T-H-M processes and to build confidence in mathematical models and computer codes. The coupled T-H-M experiment is one of tasks in DECOVALEX (DEvelopment of COupled models and their VALidation against EXperiments) project which is an international co-operative project and it is defined as Task 2. The Task 2 for the DECOVALEX project are divided into three subtasks (A-C) in accordance with the programme and availability of data, called subtasks. This note describes the results of subtask C. Subtask C is a coupled thermo-hydro-mechanical analysis in the near field.