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Ito, Chikara; Naito, Hiroyuki; Nishimura, Akihiko; Oba, Hironori; Wakaida, Ikuo; Sugiyama, Akira; Chiyatani, Keiji
Journal of Nuclear Science and Technology, 51(7-8), p.944 - 950, 2014/07
Times Cited Count:27 Percentile:90.9(Nuclear Science & Technology)In the Fukushima Daiichi Nuclear Power Station, it is necessary to survey the locations and conditions of fuel debris inside reactor pressure vessels or primary containment vessels under water and radiation environment in preparation for removing fuel debris. An optical fiber is well known for features such as signal transmission, light weight, superior insulation performance, water resistance and electromagnetic noise resistance. These features allow the optical fiber to simplify the instrumentation systems for in-vessel inspection, as long as provide that the optical fiber can be used under high radiation dose environment. The radiation resistance of an optical fiber was improved by increasing the amount of hydroxyl up to 1000 ppm in pure silica fiber. The improved optical fibers were irradiated with -ray up to 1 10 Gy using a Co source. They indicated a large peak around 600 nm and a peak tail from ultraviolet region, but no large absorption in infrared region except a hydroxyl absorption peak of 945 nm. We have confirmed that the optical fiber containing 1000 ppm hydroxyl has enough radiation resistance for radiation induced transmission losses and the infrared imaging is effective for observation under high radiation doses.
Shirai, Hiroshi; Takizuka, Tomonori; Kikuchi, Mitsuru; Mori, Masahiro; Nishitani, Takeo; Ishida, Shinichi; Kamada, Yutaka; Sato, Masayasu; Isei, Nobuaki; Koide, Yoshihiko; et al.
IAEA-CN-60/A2-17, 0, p.355 - 364, 1995/00
no abstracts in English
; *; *; *; ; *; *; Naito, Keiji
Chemistry Letters, 1973(9), p.1015 - 1016, 1973/09
no abstracts in English
*; Naito, Keiji
JAERI 4045, 30 Pages, 1968/03
no abstracts in English
Naito, Keiji
Yogyo Kyokia-Shi, 75(862), p.163 - 174, 1967/06
no abstracts in English
Naito, Keiji;
Denki Kagaku, 35, p.319 - 330, 1967/00
no abstracts in English
; *; Naito, Keiji
J.Am.Ceram.Soc., 50(6), p.308 - 311, 1967/00
Times Cited Count:6no abstracts in English
Naito, Keiji
Kagaku Kyoiku, 15(3), p.305 - 315, 1967/00
no abstracts in English
Naito, Keiji;
Solid State Communications, 5, p.349 - 352, 1967/00
Times Cited Count:28no abstracts in English
Naito, Keiji
Nihon Kinzoku Gakkai Kaiho, 5(3), p.159 - 172, 1966/00
no abstracts in English
Naito, Keiji; *
Journal of Physics and Chemistry of Solids, 26(11), p.1673 - 1677, 1965/00
Times Cited Count:21no abstracts in English
Naito, Keiji; *; *
Journal of Physics and Chemistry of Solids, 25(11), p.1679 - 1684, 1965/00
no abstracts in English
; ; *; Naito, Keiji; *; *; *
JAERI 1051, 51 Pages, 1964/01
no abstracts in English
Naito, Keiji; Noboru Oi*; Tadao Ohno*
Journal of Nuclear Science and Technology, 1(8), p.284 - 289, 1964/00
no abstracts in English
*; Naito, Keiji; *
JAERI 4025, 38 Pages, 1963/11
no abstracts in English
Naito, Keiji;
J.Phys.Chem., 66(6), p.983 - 988, 1962/00
no abstracts in English
Naito, Keiji;
J.Phys.Chem., 66(6), p.989 - 995, 1962/00
no abstracts in English
Naito, Keiji; *; *
Nihon Genshiryoku Gakkai-Shi, 4(11), p.754 - 758, 1962/00
no abstracts in English
; Naito, Keiji; *
Nihon Genshiryoku Gakkai-Shi, 4(2), p.111 - 117, 1962/00
no abstracts in English
Sugimoto, Asao; Takeda; Furuhashi, Akira; Katsuragi, Satoru; Hirota, Jitsuya; Naito, Keiji; Kondo, Yasuko; Nagasaki, Ryukichi; Yamazaki, Yasaburo; Kuroi, Hideo; et al.
JAERI 4018, 52 Pages, 1961/06
no abstracts in English