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Nakamura, Shoji; Shibahara, Yuji*; Endo, Shunsuke; Kimura, Atsushi
Journal of Nuclear Science and Technology, 60(11), p.1361 - 1371, 2023/11
Times Cited Count:1 Percentile:68.31(Nuclear Science & Technology)The thermal-neutron capture cross section () and resonance integral (I) for Nb among nuclides for decommissioning were measured by an activation method and the half-life of Nb by mass analysis. Niobium-93 samples were irradiated with a hydraulic conveyer installed in the research reactor in Institute for Integral Radiation and Nuclear Science, Kyoto University. Gold-aluminum, cobalt-aluminum alloy wires were used to monitor thermal-neutron fluxes and epi-thermal Westcott's indexes at an irradiation position. A 25-m-thick gadolinium foil was used to sort out reactions ascribe to thermal-and epi-thermal neutrons. Its thickness provided a cut-off energy of 0.133 eV. In order to attenuate radioactivity of Ta due to impurities, the Nb samples were cooled for nearly 2 years. The induced radio activity in the monitors and Nb samples were measured by -ray spectroscopy. In analysis based on Westcott's convention, the and I values were derived as 1.110.04 barn and 10.50.6 barn, respectively. After the -ray measurements, mass analysis was applied to the Nb sample to obtain the reaction rate. By combining data obtained by both -ray spectroscopy and mass analysis, the half-life of Nb was derived as (2.000.15)10 years.
Ohira, Saki; Iida, Yoshihisa
Proceedings of Waste Management Symposia 2023 (WM2023) (Internet), 10 Pages, 2023/02
The sorption distribution coefficient (d) of niobium-94 (Nb-94) on minerals is one of the important parameters in safety assessment of radioactive waste disposal. In a previous study, the d values of Nb under alkali condition in the presence of Ca, were two orders of magnitude higher than those in the presence of Na. In this study, Nb sorption experiments were performed to reexamine the effect of Ca on Nb sorption on clay minerals, and blank tests were performed to check for precipitation formation. The results showed that the Nb sorption onto montmorillonite and illite, did not depend on the Ca concentration, and d values obtained in the presence of Ca were the same as those in the absence of Ca. A sorption model assuming sorption by complexation on the mineral surface was developed and then calculated using the geochemical calculation code. The model with the surface species X_ONb(OH) and X_ONb(OH) represented trends in the data obtained.
Endo, Shunsuke; Kimura, Atsushi; Nakamura, Shoji; Iwamoto, Osamu; Iwamoto, Nobuyuki; Rovira Leveroni, G.; Terada, Kazushi*; Meigo, Shinichiro; Toh, Yosuke; Segawa, Mariko; et al.
Journal of Nuclear Science and Technology, 59(3), p.318 - 333, 2022/03
Times Cited Count:6 Percentile:64.12(Nuclear Science & Technology)Yamaguchi, Tetsuji; Ohira, Saki; Hemmi, Ko; Barr, L.; Shimada, Asako; Maeda, Toshikatsu; Iida, Yoshihisa
Radiochimica Acta, 108(11), p.873 - 877, 2020/11
Times Cited Count:7 Percentile:65.65(Chemistry, Inorganic & Nuclear)Motooka, Takafumi; Kiuchi, Kiyoshi
Materials Transactions, 43(5), p.1220 - 1224, 2002/05
Times Cited Count:2 Percentile:23.92(Materials Science, Multidisciplinary)Refractory materials such as zirconium, niobium and titanium alloys with excellent corrosion resistance in boiling nitric acid have been selected for use as structural materials of spent fuel reprocessing equipment. The fatigue crack growth rates of these materials were investigated by load control tests as a function of the stress intensity factor range in boiling 3N nitric acid and in air at room temperature. The fracture surfaces were observed by SEM. The fatigue crack growth rates of zirconium and niobium were enhanced in boiling nitric acid compared with those in air at room temperature. Acceleration effect due to corrosion fatigue was not observed in the crack growth of Ti-5Ta alloy. The fracture surfaces of Ti-5Ta alloy showed the ductile striation in both environments. On the other hand, the fracture surfaces of niobium represented the fatigue striation in air and the brittle striation due to corrosion in nitric acid. The fracture surfaces of zirconium in nitric acid showed brittle fracture and the ductile fracture related to stress corrosion cracking.
Kiuchi, Kiyoshi; Ioka, Ikuo; Tachibana, Katsumi; Suzuki, Tomio; Fukaya, Kiyoshi*; Inohara, Yasuto*; Kambara, Shozo; Kuroda, Yuji*; Miyamoto, Satoshi*; Ogura, Kazutomo*
JAERI-Research 2002-008, 63 Pages, 2002/03
no abstracts in English
Motooka, Takafumi; Kiuchi, Kiyoshi
Proceedings of the 2nd International Conference on Environment Sensitive Cracking and Corrosion Damage (ESCCD 2001), p.374 - 378, 2001/11
Refractory metals such as Zr, Nb and Ti alloys with the excellent corrosion resistance in boiling nitric acid have been selected for structural materials of spent fuel reprocessing equipment. On this study, the fatigue crack growth rate of these materials was investigated by load control tests as a function of the stress intensity in boiling nitric acid and in air at room temperature. The fracture surface was observed by scanning electron microscopy. The crack growth rate of Zr and Nb was enhanced in boiling nitric acid compared with that in air at room temperature. Acceleration effect due to corrosion fatigue was not observed in the crack growth of Ti-5Ta alloy. The fracture surfaces of Ti-5Ta alloy showed the ductile striation in both environments. On the other hand, the fracture surfaces of Nb showed the ductile striation in air and brittle striation in nitric acid. The anodic dissolution was interpreted to the acceleration factor on corrosion fatigue of Nb. The fracture surfaces of Zr in nitric acid showed both brittle and ductile fracture with fluted pattern due to SCC.
Shiratori, Tetsuo; Serizawa, Hiroyuki; Fukuda, Kosaku; Fujino, Takeo*; Sato, Nobuaki*; Yamada, Kota*
JAERI-Research 2000-045, 74 Pages, 2000/09
no abstracts in English
; Ishii, Tetsuro; Ikezoe, Hiroshi
Nuclear Instruments and Methods in Physics Research A, 421, p.426 - 432, 1989/00
no abstracts in English
JAERI-M 85-049, 197 Pages, 1985/05
no abstracts in English
;
JAERI-M 84-071, 41 Pages, 1984/04
no abstracts in English
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Physical Review B, 31(2), p.791 - 797, 1984/00
Times Cited Count:45 Percentile:87.56(Materials Science, Multidisciplinary)no abstracts in English
;
Surface and Interface Analysis, 6(4), p.171 - 173, 1984/00
Times Cited Count:37 Percentile:77.62(Chemistry, Physical)no abstracts in English
*; Katsuta, Hiroji; Furukawa, Kazuo; *
Journal of Nuclear Materials, 97(1-2), p.59 - 66, 1981/00
Times Cited Count:9 Percentile:73.24(Materials Science, Multidisciplinary)no abstracts in English
Katsuta, Hiroji; Furukawa, Kazuo
Journal of Nuclear Materials, 71(1), p.95 - 104, 1977/01
Times Cited Count:10no abstracts in English
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Radiat.Eff., 33, p.253 - 256, 1977/00
no abstracts in English
Katsuta, Hiroji; *; Furukawa, Kazuo
Journal of Nuclear Materials, 61(3), p.324 - 325, 1976/03
no abstracts in English
Nihon Kinzoku Gakkai-Shi, 14(7), p.521 - 530, 1975/07
no abstracts in English
;
Journal of the Physical Society of Japan, 35(3), p.750 - 753, 1973/03
Times Cited Count:17no abstracts in English
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Journal of Radioanalytical Chemistry, 5, p.201 - 206, 1970/00
no abstracts in English