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generation by reaction with Ru-La-Na mix nitrates and raw materials for vitrificationNagai, Takayuki; Kobayashi, Hidekazu; Okamoto, Yoshihiro; Sato, Nobuaki*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*; Seki, Katsumi*
no journal, ,
It is thought that a generated ruthenium compound grows from a high level radioactive liquid waste into RuO crystal by reacting to raw materials for the vitrification process. In this study, the generation reaction to RuO was confirmed by heating Ru-La-Na mix nitrates and the raw materials.
Tsuchiya, Harufumi; Kitatani, Fumito; Kureta, Masatoshi; Maeda, Makoto
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no abstracts in English
Ozu, Akira; Maeda, Makoto; Komeda, Masao; Tobita, Hiroshi; Kureta, Masatoshi
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no abstracts in English
Tada, Kenichi; Nagaya, Yasunobu
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JAEA has been developing the nuclear data processing code FRENDY (FRom Evaluated Nuclear Data librarY to any application). In this presentation, construction of the probability table in the unresolved resonance region is described.
Kikuchi, Takeo; Tada, Kenichi; Suyama, Kenya
no journal, ,
To estimate the prediction accuracy of the integrated burn up analysis code system SWAT4, we compared the calculation results of SWAT4 and the PIE data of the BWR fuel which was measured by JAERI in 1990s. Comparison results are indicated that the C/E value of major heavy nuclei, e.g., U and Pu, is approximately 1.0. The calculation results are also indicated that some fission products, e.g., Sm, have the larger difference.
Zaima, Naoki; Naganuma, Masaki; Sakao, Ryota
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no abstracts in English
Iwai, Yasunori; Kondo, Akiko*; Edao, Yuki; Sato, Katsumi; Kubo, Hitoshi*; Oshima, Yusuke*
no journal, ,
Effect of halogenated gas on detritiation efficiency of the detritiation system has been investigated taking an event of off normal event such as fire into consideration. Concerning the activity of platinum catalyst for oxidation of tritium, we have evaluated the steep decrease in activity of platinum catalyst in the presence of halogenated gas. In order to avoid the steep decrease in activity, a noble catalyst alloyed with platinum and palladium showed an outstanding proof. In addition, the halogenated acid produced over catalyst surface affects the activity of catalyst. As for water absorber, a molecular sieve decreased its water absorbing capacity in the presence of halogenated gas.
Furutachi, Naoya; Minato, Futoshi; Iwamoto, Osamu
no journal, ,
To establish the nuclear transmutation system for the long-lived fission products (LLFPs), it is desired to improve precision of the simulation calculation for the transmutation system. To achieve this, nuclear data of various nuclei produced via the nuclear transmutation of LLFPs are also important. However, it is expected that unstable nuclei with no available experimental data are produced via the nuclear transmutation. One of the physical quantity that is very difficult to predict with no experimental data is the thermal neutron capture cross section. The thermal neutron capture cross section is dominated by the energy and width of the first resonance, and slight variation of them can change the thermal neutron capture cross section drastically. While it is very difficult to determine them with high precision, it is known that a resonance width follows Porter-Thomas distribution because of complexity and randomness of a nuclear structure, and a resonance spacing follows Wigner distribution. In this work, we calculate the thermal neutron capture cross section by using the statistical property of the resonance parameters with Monte Carlo method. The calculation result is obtained as a probability distribution of the thermal neutron capture cross section. We calculated approximately 250 nuclei that have experimental data, and found that the dispersion of the experimental data is well explained by the calculated probability distribution.
Minato, Futoshi
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no abstracts in English
Yamashita, Susumu; Takase, Kazuyuki; Monji, Hideaki*; Yoshida, Hiroyuki
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no abstracts in English
4 bundleLiu, W.; Nagatake, Taku; Jiao, L.; Shibata, Mitsuhiko; Komatsu, Masao*; Takase, Kazuyuki; Yoshida, Hiroyuki
no journal, ,
To improve and validate the prediction accuracy of two - phase codes, Japan Atomic Energy Agency is working on the measurement of void faction distribution in rod bundles with using wire mesh sensors, under high pressure and high temperature conditions (2MPa, 212
C). The test section is a 44 rod bundle, in which two three - layer 99 wire mesh sensors are installed at two different axial positions. As the first step of the experiment, to validate the measuring system, we performed experiments in water - air system under atmospheric pressure, with using water and air flow rates as parameters. Void fraction distributions in the sub-channels of the rod bundle were derived in a wide flow pattern from bubbly flow to slug flow. The water flow rate, from the viewpoint of considering the natural circulation after reactor scrum, was lower than 600 kg/m
s. The data will be used to validate the void fraction correlations and two-phase evaluation codes.
Osaka, Masahiko; Miwa, Shuhei; Nakajima, Kunihisa; Di Lemma, F. G.; Suzuki, Chikashi; Nagase, Fumihisa
no journal, ,
Chemical behavior of fission product (FP) are of crucial importance for the improvement of FP release and transport behavior under the severe accident. Fundamental research on FP sorption behavior and evaluation of FP chemical composition in the reactor are introduced.
Nagaishi, Ryuji; Motooka, Takafumi; Yamagishi, Isao; Inoue, Masao; Matsumura, Taichi
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no abstracts in English
Satou, Yukihiko*; Sueki, Keisuke*; Sasa, Kimikazu*; Minowa, Haruka*; Yoshikawa, Hideki; Fujiwara, Kenso; Nakama, Shigeo
no journal, ,
We separated radioactive particles from soil and dust sample obtained around Fukushima Dai-ichi Nuclear Power Plant. Separated all particles can categorize unit-1 and unit-2 origin. And 
Sb was detected from unit-1 origin samples. Moreover, radioactive particle was made up 80 weight percent silica.
Hirouchi, Jun; Takahara, Shogo; Watanabe, Masatoshi; Munakata, Masahiro
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no abstracts in English
Watanabe, Masatoshi; Takahara, Shogo; Hirouchi, Jun; Munakata, Masahiro
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no abstracts in English
Yamane, Yuichi
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For criticality accidents due to instantaneous insertion of reactivity to the system with non-linear temperature reactivity feedback, an equation has been derived based on one-point kinetics, by which equation the total fission energy is expressed as a function of initial excess reactivity and other kinetics parameters. The results obtained by using the equation and one-point kinetics code, AGNES, were compared to each other to show that the difference between them decreased with increase of excess reactivity from several ten % to 4%.
Furuta, Takuya; Takahashi, Fumiaki
no journal, ,
Precise radiation dose assessment for residents is desired for radiation protection under contaminated environment due to the accident at Fukushima Daiichi Nuclear Power Station. Evaluation of dose rates inside houses is important for this assessment as well as those outside houses by monitoring because people stays inside houses for a large part of a day. We have studied radiation dose reduction inside buildings standing on isolated flat field as the typical data. However, radiation dose reduction for houses in urban area may be different from that for isolated houses because of influence of neighboring buildings. We therefore simulated a situation of infinitely aligned houses virtually by using reflection walls placed at the boundary of geometry containing a house. The radiation dose rate inside this house was computed by transporting radiations using PHITS. We found that dose rates per unit radiation concentration inside the house was lowered as the distance between houses was reduced because of shielding effect by neighboring houses and reduction of radiation source contributed to the dose rate.
Koura, Hiroyuki; Chiba, Satoshi*
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no abstracts in English
Terunuma, Hirotaka; Tanaka, Kiwamu; Kabumoto, Hiroshi; Haginoya, Masashi; Sano, Naruto; Takahashi, Masatomi; Hoshino, Masato; Aoki, Isao; Asazuma, Shinichiro
no journal, ,
no abstracts in English