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Maruyama, Takahito; Aburadani, Atsushi; Takeda, Nobukazu; Kakudate, Satoshi; Nakahira, Masataka; Tesini, A.*
Fusion Engineering and Design, 89(9-10), p.2404 - 2408, 2014/10
Times Cited Count：6 Percentile：42.97(Nuclear Science & Technology)Takeda, Nobukazu; Aburadani, Atsushi; Tanigawa, Hisashi; Shigematsu, Soichiro; Kozaka, Hiroshi; Murakami, Shin; Kakudate, Satoshi; Nakahira, Masataka; Tesini, A.*
Fusion Engineering and Design, 88(9-10), p.2186 - 2189, 2013/10
Times Cited Count：2 Percentile：18.63(Nuclear Science & Technology)R&D for rail deployment equipment was performed for the ITER blanket remote handling system. The target torque for the automatic operation was investigated. The result shows that the 20% of the rated torque is adequate as the torque limitation for the automatic operation. A schedule for the procurement of the blanket remote handling system, which will be delivered to the ITER in 2020, was also shown.
Aburadani, Atsushi; Takeda, Nobukazu; Shigematsu, Soichiro; Murakami, Shin; Tanigawa, Hisashi; Kakudate, Satoshi; Nakahira, Masataka*; Hamilton, D.*; Tesini, A.*
Fusion Engineering and Design, 88(9-10), p.1978 - 1981, 2013/10
Times Cited Count：2 Percentile：18.63(Nuclear Science & Technology)no abstracts in English
Shigematsu, Soichiro; Tanigawa, Hisashi; Aburadani, Atsushi; Takeda, Nobukazu; Kakudate, Satoshi; Mori, Seiji*; Nakahira, Masataka*; Raffray, R.*; Merola, M.*
Fusion Engineering and Design, 87(7-8), p.1218 - 1223, 2012/08
Times Cited Count：6 Percentile：38.04(Nuclear Science & Technology)The current design of the ITER blanket system is a modular configuration and a total of 440 blanket modules are to be installed in the ITER vacuum vessel. Each blanket module consists of the first wall (FW) and the shield block (SB). The FW receives a high heat load from the plasma. The SB shields components from the neutrons generated by the nuclear fusion reaction. The FW will be damaged by the heat load and neutrons, so it requires scheduled replacement. For the FW replacement, cutting/welding tools for the cooling pipes must be able to conduct the following operations: access and cut/weld the pipe from the inside of the cooling pipe. The cutting tool for the pipe end is required to cut flat plate circularly from the surface side of the FW. This paper describes the current status of R&D of the cutting tools for maintenance of the cooling pipe of the FW.
Takeda, Nobukazu; Kakudate, Satoshi; Matsumoto, Yasuhiro; Kozaka, Hiroshi; Aburadani, Atsushi; Negishi, Yusuke; Nakahira, Masataka*; Tesini, A.*
Fusion Engineering and Design, 85(7-9), p.1190 - 1195, 2010/12
Times Cited Count：2 Percentile：17.46(Nuclear Science & Technology)Several R&Ds for the ITER blanket remote handling system had been performed from the Engineering Design Activity phase until now and only several technical issues regarding the control system remained such as noise caused by slip ring, control of cable handling system, signal transmission through very long cable and radiation-hard amplifier. This study concentrates on these issues. As a conclusion, major issues for the control system have been solved and the ITER blanket remote handling system becomes further feasible.
Kita, Kenichiro; Narisawa, Masaki*; Nakahira, Atsushi*; Mabuchi, Hiroshi*; Ito, Masayoshi*; Sugimoto, Masaki; Yoshikawa, Masahito
Advances in Polymer Derived Ceramics and Composites; Ceramic Transactions, Vol.213, p.45 - 50, 2010/06
Kita, Kenichiro; Narisawa, Masaki*; Nakahira, Atsushi*; Mabuchi, Hiroshi*; Sugimoto, Masaki; Yoshikawa, Masahito
Journal of Materials Science, 45(13), p.3397 - 3404, 2010/04
Times Cited Count：11 Percentile：34.92(Materials Science, Multidisciplinary)We synthesized ceramic fibers based on silicon carbide (SiC) from polymer blends of polycarbosilane (PCS) and polymethylphenylsiloxane (PMPhS). PMPhS was compatible with PCS up to 30 mass%. The polymer blend was formed a transparent melt at temperatures higher than 513 K and the softening point was also lowered by adding PMPhS. 15 mass% of PMPhS to PCS was the most suitable condition for obtaining thin fibers with an average diameter of 14.4 
m and the ceramic yield of the cured fiber was 85.5% after pyrolysis at 1273 K. In spite of the small diameter, the resulting tensile strength at 1273 K was rather limited at 0.78 GPa. After high temperature pyrolysis at 1673
1773 K, a porous nanocrystalline SiC fiber with a unique microstructure was obtained with surface area of 70150 m
/g.
Kita, Kenichiro; Narisawa, Masaki*; Nakahira, Atsushi*; Mabuchi, Hiroshi*; Ito, Masayoshi*; Sugimoto, Masaki; Yoshikawa, Masahito
Journal of Materials Science, 45(1), p.139 - 145, 2010/01
Times Cited Count：12 Percentile：37.22(Materials Science, Multidisciplinary)The polymer blends of polycarbosilane (PCS) and polymethylohydrosiloxane with high molecular weight (PMHS-h) were prepared by freeze-drying process. Melt viscosity, themogravimetric analysis, and gas evolution from the polymer blends were analyzed. The polymer blend of HSah15 (15 mass% PMHS-h to PCS) was melt-spun to fiber form, curing by thermal oxidation and pyrolyzed at various temperatures up to 1773 K. The fibers were investigated by tensile tests, FE-SEM observation, and XRD (X-ray diffraction) analysis. After pyrolysis at 1273 K, there were amounts of pores in the cross sections of the fiber derived from HSah15, and after pyrolysis at 1773 K, no remarkable 
-SiC crystal were formed on the outside surface of the fiber derived from HSah15.
Nagata, Hidezumi*; Hirao, Norie*; Onoki, Takamasa*; Baba, Yuji; Yamasaki, Yuki*; Nakahira, Atsushi*
Journal of the Ceramic Society of Japan, 116(1350), p.216 - 219, 2008/02
Times Cited Count：10 Percentile：52.56(Materials Science, Ceramics)Bulky palladium catalyst supported on mesoporous silica (Pd-MCM-41) was successfully synthesized by hydrothermal hot-pressing method. The structure of the palladium species in Pd-MCM-41 bulk before and after heat-treatment process was investigated by X-ray diffraction (XRD), X-ray absorption near edge structure (XANES) and transmission electron microscopy (TEM). On the basis of these results, the microstructures and mesoporous properties of Pd-MCM-41 were discussed. As a result, it was revealed that the obtained Pd-MCM-41 bulks possessed a high area of over 1000 m/g and the electronic state of palladium in Pd-MCM-41 bulk is almost equal to palladium (0) metal.
Kita, Kenichiro; Narisawa, Masaki*; Nakahira, Atsushi*; Ito, Masayoshi*; Sugimoto, Masaki; Yoshikawa, Masahito
no journal, ,
no abstracts in English
Kakudate, Satoshi; Takeda, Nobukazu; Nakahira, Masataka*; Aburadani, Atsushi; Matsumoto, Yasuhiro; Kozaka, Hiroshi; Negishi, Yusuke
no journal, ,
no abstracts in English
Aburadani, Atsushi; Takeda, Nobukazu; Kakudate, Satoshi; Kubo, Tomomi*; Sugimoto, Takeru*; Nakahira, Masataka*; Tesini, A.*
no journal, ,
no abstracts in English
Aburadani, Atsushi; Kozaka, Hiroshi; Kakudate, Satoshi; Negishi, Yusuke; Matsumoto, Yasuhiro*; Nakahira, Masataka*; Tesini, A.*; Takeda, Nobukazu
no journal, ,
R&D for the major devices, rail deployment equipment and cable handling system, was performed for the ITER blanket remote handling system. Regarding the rail deployment, the relation between the Oldham's coupling used for the positioning arm and the positioning error at the end of rail was investigated. The result shows that the coupling allowing 4 mm displacement causes the positioning error of 19 mm. The possible countermeasures are suggested. Regarding the cable handling system, a possibility is shown to keep the cable tension at the adequate level by controlling the torque of the cable handling system. A schedule for the procurement of the blanket remote handling system, which will be delivered to the ITER in 2016, is also shown.
