著者

Yoichiro SHIMAZU

出版者

Atomic Energy Society of Japan

雑誌

Journal of Nuclear Science and Technology (ISSN:00223131)

巻号頁・発行日

vol.14, no.11, pp.805-810, 1977-11-25 (Released:2008-04-18)

参考文献数

6

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An evaluation is made to estimate the transient xenon behavior in an MSBR for several representative patterns of operation. Such analysis is indispensable for detailed evaluation of reactivity balance under transient conditions. The results are compared with those of a typical PWR. The xenon behavior does not differ between the two types of reactor to the extent that might be expected from the fact that in the MSBR, xenon behavior is additionally conditioned by the processes of migration into the circulating bubbles and into the graphite, as well as by diffusion therein.It is shown that the reactivity transients due to xenon buildup can be held within the range of counteraction by control rod movement for any normal change of reactor output, so long as the reactor is not shut down. After a shutdown, insertion of the control rods will not suffice to override the xenon buildup, but then the fuel processing system could be conveniently utilized to increase the quantity of 233U contained in the fuel and regain required reactivity of the core.

著者

Noboru KOBAYASHI Ichiro YAMAMOTO

出版者

Atomic Energy Society of Japan

雑誌

Journal of Nuclear Science and Technology (ISSN:00223131)

巻号頁・発行日

vol.34, no.3, pp.318-324, 1997-03-25 (Released:2008-04-18)

参考文献数

6

被引用文献数

1

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By making use of the isotope approximation; neglecting squares of relative mass differences among the isotopes, the authors derived analytically approximations to ordinary diffusion coefficients in a 3- and 4- component isotope mixture. Moreover, approximations to multi-component diffusion coefficients were given on the analogy of those to the 3- and 4-component coefficients, and these approximations were verified to satisfy constrains on the exact ordinary diffusion coefficients. For 4-component mixture of uranium hexafluoride isotopes, 234UF6-235UF6-236UF6-236UF6, composition dependences of the approximation were equal to those of the exact diffusion coefficients. In addition, relative errors between the exact and the approximations were less than 0.2% for 5-component mixture of krypton 80-82-83-84-86 isotopes.

著者

Shigeru IKUTA Kenji YOSHIHARA Takanobu SHIOKAWA

出版者

Atomic Energy Society of Japan

雑誌

Journal of Nuclear Science and Technology (ISSN:00223131)

巻号頁・発行日

vol.14, no.9, pp.661-663, 1977-09-25 (Released:2008-04-18)

参考文献数

8

被引用文献数

1

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The behaviors of CH3He+ and C2H5He+ formed by the decay of CH3T and C2H5T were studied theoretically using the STO-3G molecular orbital method and was compared with that of HHe+ in the decay of HT. It was clearly shown that the ground state daughter ions CH3He+ and C2H5He>+ dissociate instantly to give CH3+ and C2H5+ because their poten-tial energy curves are repulsive, whereas the daughter ion HHe+ in the ground state does not dissociate. The transition probability to the ground state ions of CH3He+ and of C2H5He+ are computed to be 66.5 and 64.8%, respectively. These values are in fairly good accordance with those obtained experimentally.

著者

濱口 晃 奥城 大輔 平松 綾子 中庭 明子 能勢 和夫

出版者

自動制御連合講演会

雑誌

Journal of nuclear science and technology (ISSN:00223131)

巻号頁・発行日

vol.44, no.2, pp.129-136, 2007-02-25

参考文献数

19

被引用文献数

8

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解候補の探索において、解集合の類似度の基づき探索空間の精密度を変更するアントコロニー最適化法(ACO法)を考案し、車の運転操作パターンの自動生成問題に適用した。車庫入れ問題、縦列駐車問題について数値実験を行ない、良好な結果が得られた。

著者

Katsuhiko SAGAE Akira SUZUOKI

出版者

Atomic Energy Society of Japan

雑誌

Journal of Nuclear Science and Technology (ISSN:00223131)

巻号頁・発行日

vol.22, no.11, pp.870-880, 1985-11-25 (Released:2008-04-18)

参考文献数

7

被引用文献数

2

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An analytical model for sodium pool combustion has been developed and verified by ex-periments. The model can be used to analyze sodium fire accidents in LMFBRs. It features a layer of sodium vapor between the flame and the sodium pool surface which functions to resist heat transfer. Results obtained with the model show : combustion rate increases with oxygen concentration, sodium pool temperature and gas pressure, but it decreases with in-creases in gas temperature. Calculated combustion rates agree within 15% of the experi-mental results.

著者

Endo Tomohiro Chiba Go van Rooijen Willem Frederik Geert Yamanaka Masao Pyeon Cheol Ho

出版者

Taylor & Francis

雑誌

Journal of Nuclear Science and Technology (ISSN:00223131)

巻号頁・発行日

vol.55, no.4, pp.450-459, 2018

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Nuclear data-induced uncertainties of neutronics parameters (neutron multiplication factor keff, one-point kinetics parameters and prompt neutron decay constant α) are quantified for lead-bismuth zoned accelerator-driven system experiments at the Kyoto University Critical Assembly, in order to contribute validation for subcritical core analysis. The random sampling technique using SCALE6.2.1/Sampler/NEWT/PARTISN is utilized for the validation and the uncertainty quantification, because the random sampling technique is applicable for a problem which is not easy to apply the perturbation theory. Consequently, it is confirmed that the numerical results of α reasonably agree with the experimental ones, compared with the nuclear data-induced uncertainties. In addition, it is clarified that the nuclear data-induced correlations between α and keff and between α and neutron generation time Λ are strongly negative and positive, respectively. This fact implies that the numerical predictions of keff and Λ can be improved by the data assimilation technique using subcritical experimental results of α, which can be directly measured even for a deep subcritical system.

著者

TAKEDA Hiroshi YAMAMOTO Yutaka

出版者

Atomic Energy Society of Japan

雑誌

Journal of Nuclear Science and Technology (ISSN:00223131)

巻号頁・発行日

vol.13, no.7, pp.372-381, 1976

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For analyzing the mixing of particles in a spouted bed, a model is proposed, which assumes that : (a) the spouted bed consists of a spout part characterized by perfect mixing and an annulus part occupied by piston flow, (b) the ingress of particles from annulus into spout takes place within a zone below a depth h below the top of the annulus, and (c) the rate of ingress of particles into the spout is constant throughout the bed. <BR>The time-dependence of the concentration <I>C</I>*(<I>t</I>) of marked particles within the spout can be calculated with this model assuming suitable values for unmeasurable parameters. <BR>The value of <I>C</I>*(<I>t</I>) was measured from mixing experiments undertaken using alumina particles, to which a small batch of marked alumina particles was dropped transiently onto the bed in stable operation. <BR>Comparing the experimental data with the calculated results, it was found that : (a) the mixing of particles in the bed can be satisfactorily described with this model, pro-vided that a suitable correction is added to the quantity of particles present in the spout to account for the existence of mixing in the annulus, whereas the model assumed piston flow ; (b) the upper edge of the ingress zone of particles from the spout into the annulus is located in the conical part of the bed. Increasing the flow rate of spouting air short-ened the cycle time of particles, while the mixing rate within one cycle was not affected to any significant extent by changes in flow rate.

著者

KISHIDA Kazuo YAMAWAKI Michio KANNO Masayoshi

出版者

Atomic Energy Society of Japan

雑誌

Journal of Nuclear Science and Technology (ISSN:00223131)

巻号頁・発行日

vol.15, no.12, pp.919-925, 1978

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Corrosion of Type 304 stainless steel by molten Cs<SUB>2</SUB>O<SUB>3</SUB>-CsO<SUB>2</SUB> has been investigated at 690 and 800°C. The Cs<SUB>2</SUB>O<SUB>3</SUB>-CsO<SUB>2</SUB> mixture was selected as corroding agent in order to clarify the corrosion behavior of stainless steel at a considerably high oxygen potential. At the initial stage a uniform Fe<SUB>3</SUB>O<SUB>4</SUB> layer is formed and is then removed. After the removal of the oxide film intergranular penetration proceeds into the alloy substrate. Chromium-containing oxides are formed as corrosion products at the grain boundaries. After the grain boundary penetration has continued for a while, a Cr-depleted surface alloy layer is formed, which blocks further progressing of the intergranular penetration. Then, this Cr-depleted layer is detached, inducing the restart of the intergranular pene-tration. Compared to the reported intergranular penetration rates of stainless steel due to Cs<SUB>2</SUB>O-Cs<SUB>2</SUB>O<SUB>2</SUB>, those due to Cs<SUB>2</SUB>O<SUB>3</SUB>-CsO<SUB>2</SUB> obtained in this study were generally lower, and changed in a more complicated fashion with time.

著者

NAKAGAWA Tsuneo SHIBATA Keiichi CHIBA Satoshi FUKAHORI Tokio NAKAJIMA Yutaka KIKUCHI Yasuyuki KAWANO Toshihiko KANDA Yukinori OHSAWA Takaaki MATSUNOBU Hiroyuki KAWAI Masayoshi ZUKERAN Atsushi WATANABE Takashi IGARASI Sin-iti KOSAKO Kazuaki ASAMI Tetsuo

出版者

Atomic Energy Society of Japan

雑誌

Journal of nuclear science and technology (ISSN:00223131)

巻号頁・発行日

vol.32, no.12, pp.1259-1271, 1995-12-25

被引用文献数

98 166

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The revision work of JENDL-3 has been made by considering feedback information of various benchmark tests. The main revised quantities are the resonance parameters, capture and inelastic scattering cross sections, and fission spectra of main actinide nuclides, the total and inelastic scattering cross sections of structural materials, the resonance parameters the capture and inelastic scattering cross sections of fission products, and the γ-ray production data. The revised data were released as JENDL-3.2 in June 1994. The preliminary benchmark tests indicate that JENDL-3.2 predicts various reactor characteristics more successfully than the previous version of JENDL-3.1.

著者

OYAMA Yukio YAMAGUCHI Seiya MAEKAWA Hiroshi

出版者

Atomic Energy Society of Japan

雑誌

Journal of Nuclear Science and Technology (ISSN:00223131)

巻号頁・発行日

vol.25, no.5, pp.419-428, 1988

被引用文献数

5

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Angular neutron fluxes leaking from the surface of lithium-oxide and graphite slab assemblies have been measured with irradiation of D-T neutrons. The spectrum measurement was performed using the time-of-flight technique with an NE213 scintillation detector. The thicknesses of the slabs were 0.6 to 5 mean free path for 14.8 MeV neutrons, and the measured leaking angles of the angular fluxes were 0.0°, 12.2°, 24.9°, 41.8° and 66.8°. The experimental results have been compared with the results calculated by the continuous energy Monte Carlo transport code MCNP, using the data in the JENDL-3PR1, -3PR2, and ENDF/B-V nuclear data files. The comparisons between the experimental and calculated results show that the data of <SUP>7</SUP>Li in JENDL-3PR2 is improved for the secondary emission spectra of the 4.63 MeV level and (n, 2n) reactions; the angular distributions of 3rd- and 4th-level inelastic reactions of C in the JENDLs are questionable. The thickness dependences for high energy neutrons also suggest that the total cross section of <SUP>7</SUP>Li and the elastic cross sections of C are slightly inadequate.

著者

Sato Satoshi Verzilov Yury Ochiai Kentaro WADA Masayuki KUTSUKAKE Chuzo TANAKA Shigeru ABE Yuichi SEKI Masakazu OGINUMA Yoshikazu KAWABE Masaru NISHITANI Takeo KONNO Chikara

出版者

Atomic Energy Society of Japan

雑誌

Journal of nuclear science and technology (ISSN:00223131)

巻号頁・発行日

vol.44, no.4, pp.657-663, 2007-04-25

著者

IKEZOE Yasumasa SATO Shoichi ONUKI Kaoru MORISHITA Norio NAKAMURA Tomoo KATSUMURA Yosuke TABATA Yoneho

出版者

Atomic Energy Society of Japan

雑誌

Journal of Nuclear Science and Technology (ISSN:00223131)

巻号頁・発行日

vol.21, no.9, pp.722-724, 1984

被引用文献数

1

著者

Chino Masamichi Nakayama Hiromasa Nagai Haruyasu TERADA Hiroaki KATATA Genki YAMAZAWA Hiromi

出版者

Atomic Energy Society of Japan

雑誌

Journal of nuclear science and technology (ISSN:00223131)

巻号頁・発行日

vol.48, no.7, pp.1129-1134, 2011-07-01

被引用文献数

27

著者

Amano Hikaru Takahashi Tomoyuki Uchida Shigeo MATSUOKA Syungo IKEDA Hiroshi HAYASHI Hiroko KUROSAWA Naohiro

出版者

Atomic Energy Society of Japan

雑誌

Journal of nuclear science and technology (ISSN:00223131)

巻号頁・発行日

vol.40, no.11, pp.975-979, 2003-11-25

被引用文献数

2