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Shimokita, Keisuke*; Yamamoto, Katsuhiro*; Miyata, Noboru*; Nakanishi, Yohei*; Shibata, Motoki*; Takenaka, Mikihito*; Yamada, Norifumi*; Seto, Hideki*; Aoki, Hiroyuki; Miyazaki, Tsukasa*
Soft Matter, 19(11), p.2082 - 2089, 2023/03
Times Cited Count:0 Percentile:0(Chemistry, Physical)Shimokita, Keisuke*; Yamamoto, Katsuhiro*; Miyata, Noboru*; Arima-Osonoi, Hiroshi*; Nakanishi, Yohei*; Takenaka, Mikihito*; Shibata, Motoki*; Yamada, Norifumi*; Seto, Hideki*; Aoki, Hiroyuki; et al.
Langmuir, 38(41), p.12457 - 12465, 2022/10
Times Cited Count:0 Percentile:0(Chemistry, Multidisciplinary)Imai, Sahori*; Arakawa, Masato*; Nakanishi, Yohei*; Takenaka, Mikihito*; Aoki, Hiroyuki; Ouchi, Makoto*; Terashima, Takaya*
Macromolecules, 55(20), p.9113 - 9125, 2022/10
Times Cited Count:3 Percentile:24.75(Polymer Science)Ikami, Takaya*; Watanabe, Yuki*; Ogawa, Hiroki*; Takenaka, Mikihito*; Yamada, Norifumi*; Ouchi, Makoto*; Aoki, Hiroyuki; Terashima, Takaya*
ACS Macro Lett (Internet), 10(12), p.1524 - 1528, 2021/12
Times Cited Count:8 Percentile:46.56(Polymer Science)Aoki, Hiroyuki; Ogawa, Hiroki*; Takenaka, Mikihito*
Langmuir, 37(1), p.196 - 203, 2021/01
Times Cited Count:2 Percentile:14.19(Chemistry, Multidisciplinary)Furusawa, Akinori; Nishimura, Akihiko; Takebe, Toshihiko*; Nakamura, Masaki*; Takenaka, Yusuke*; Saijo, Shingo*; Nakamoto, Hiroyuki*
E-Journal of Advanced Maintenance (Internet), 9(2), p.44 - 51, 2017/08
The aim of this work is to investigate the applicability of ultrasonic guided wave for evaluation of laser beam butt-welding quality. Ten in total test pipes having welding seam is prepared. Two piece of pipe are jointed and continuous laser beam is irradiated on the edges, varying laser irradiation power, welding side and surface profile of the adjacent edges of the pipe. Ultrasonic guided wave testing experiment is performed on the pipes. Torsional mode guided wave is excited by EMAT. The experimental results are analyzed and issues are discussed. The reflection wave bullet from the poor interface of the welding seam is clearly observed, whereas no reflection from fine welded line. From the aspect of laser irradiation power, welding side and surface profile of the adjacent edges, the relation between the interface condition and detection wave bullet are analyzed. It is found that the ultrasonic guided wave technologies have the potential for evaluating laser beam butt-welding seam.
Abe, Hiroshi; Shimomura, Takuya; Tokuhira, Shinnosuke*; Shimada, Yukihiro*; Takenaka, Yusuke*; Furuyama, Yuta*; Nishimura, Akihiko; Uchida, Hirohisa*; Daido, Hiroyuki; Oshima, Takeshi
Proceedings of 7th International Congress on Laser Advanced Materials Processing (LAMP 2015) (Internet), 4 Pages, 2015/08
A short pulse laser (the nanosecond and femtosecond) was applied to hydrogen absorbing alloys surface layer, and a surface modification experiment was put into effective to aim at improvement of hydrogen adsorption functionally. It was investigated about correlation between an initial hydrogen absorption reaction rate of hydrogen alloys and a laser irradiation in this research. The laser irradiation condition was done with pulse width 100 fsec and energy 0.2 - 3.4 mJ/pulse. It blazed down on hydrogen absorbing alloys (LaNiAl) and changed local order in the surface. As a result, the initial hydrogen absorption reaction rate was 1.5 - 3.0 times as fast as a irradiated sample, and the result and laser irradiated sample found out that a hydrogen absorption function improves. A laser irradiation can conclude to be effective in surface modification of the hydrogen storage materials.
Nishimura, Akihiko; Takenaka, Yusuke*; Furuyama, Takehiro*; Shimomura, Takuya; Terada, Takaya; Daido, Hiroyuki
Journal of Laser Micro/Nanoengineering, 9(3), p.221 - 224, 2014/11
Times Cited Count:0 Percentile:0(Nanoscience & Nanotechnology)Heat resistant FBG sensors were developed by femtosecond laser processing to apply them to high temperature operated piping system of nuclear power plants. The FBG sensor was installed on the surface of a steel blade and a vibration test was conducted to detect the resonant vibration frequency of the vibrating blade. The FBG sensor had the heatproof performance at 600C. A frequency stabilized sensing system using a tunable laser was tested for structural health monitoring in daily operation of nuclear power plants. The FBG sensor was installed on the surface of a steel blade for vibration induced strain measurements. Welding, brazing, soldering and noble metal powder adhesive were discussed for molding the FBG sensors.
Nishimura, Akihiko; Takenaka, Yusuke*; Furuyama, Takehiro*; Shimomura, Takuya; Terada, Takaya; Daido, Hiroyuki
Proceedings of 1st Smart Laser Processing Conference 2014 (SLPC 2014), 4 Pages, 2014/04
Heat resistant FBG sensors were developed by femtosecond laser processing. In order to apply them to piping system of nuclear power plants, vibration test under high temperature was demonstrated. The FBG sensor had the heatproof performance at 600C. A frequency stabilized sensing system using a tunable laser was tested for structural health monitoring in daily operation of nuclear power plants. The FBG sensor was installed on the surface of a steel blade for vibration induced strain measurements. Welding, brazing, soldering and noble metal powder adhesive were discussed for molding the FBG sensors.
Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05
Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.
Koike, Masato; Ishino, Masahiko; Imazono, Takashi; Sano, Kazuo*; Sasai, Hiroyuki*; Hatayama, Masatoshi*; Takenaka, Hisataka*; Heimann, P. A.*; Gullikson, E. M.*
Spectrochimica Acta, Part B, 64(8), p.756 - 760, 2009/08
Times Cited Count:9 Percentile:42.89(Spectroscopy)W/C and Co/SiO multilayer laminar-type holographic plane gratings (groove density 1/1200 lines /mm) in the 1-8 keV region are developed. For the Co/SiO grating the diffraction efficiencies of 0.41 and 0.47 at 4 and 6 keV, respectively, and for the W/C grating 0.38 at 8 keV are observed. Taking advantage of the outstanding high diffraction efficiencies into practical soft X-ray spectrographs a Mo/SiO multilayer varied-line-spacing (VLS) laminar-type spherical grating (1/2400 lines /mm) is also developed for use with a flat field spectrograph in the region of 1.7 keV. For the Mo/SiO multilayer grating the diffraction efficiencies of 0.05-0.20 at 0.9-1.8 keV are observed. The FWHM's of the measured line profiles of Hf-M (1644.6 eV), Si-K (1740.0 eV),and W-M (1775.4 eV) are 13.7 eV, 8.0 eV, and 8.7 eV, respectively. It shows the validity of multilayer lamina-type gratings in the region.
Takeno, Hiroyuki*; Uehara, Hiroki*; Murakami, Shozo*; Takenaka, Mikihito*; Kim, M.*; Nagasawa, Naotsugu; Sasaki, Sono*
Journal of Applied Crystallography, 40(s1), p.s656 - s661, 2007/04
Times Cited Count:1 Percentile:14.32(Chemistry, Multidisciplinary)no abstracts in English
Koike, Masato; Ishino, Masahiko; Heimann, P. A.*; Imazono, Takashi; Takenaka, Hisataka*; Hatayama, Masatoshi*; Sasai, Hiroyuki*; Gullikson, E. M.*; Sano, Kazuo*
AIP Conference Proceedings 879, p.647 - 650, 2007/01
no abstracts in English
Ishino, Masahiko; Heimann, P. A.*; Sasai, Hiroyuki*; Hatayama, Masatoshi*; Takenaka, Hisataka*; Sano, Kazuo*; Gullikson, E. M.*; Koike, Masato
Applied Optics, 45(26), p.6741 - 6745, 2006/09
Times Cited Count:12 Percentile:49.88(Optics)no abstracts in English
Kawai, Masayoshi*; Furusaka, Michihiro*; Kikuchi, Kenji; Kurishita, Hiroaki*; Watanabe, Ryuzo*; Li, J.*; Sugimoto, Katsuhisa*; Yamamura, Tsutomu*; Hiraoka, Yutaka*; Abe, Katsunori*; et al.
Journal of Nuclear Materials, 318, p.35 - 55, 2003/05
R&D works for MW class solid target composed of tungsten to produce pulsed intense neutron source has been made in order to construct a future scattering facility. Three methods were investigated to prevent corrosion of tungsten from water; those are hipping, brazing and electric coating in molten salt bath. Hipping condition was optimized to be 1500 degree C in the previous work: here small punch test shows highest load for crack initiation of hipped materials at the boundary of W/Ta. The basic techniques for the other two methods were developed. Erosion test showed that uncovered W is susceptible of flowing water velocity. At high velocity w is easy to be eroded. For solid target design slab type and rod type targets were studied. As long as the optimized neutron performance is concerned, 1MW solid target is better than mercury target.
Tang, H.; Daido, Hiroyuki; Kishimoto, Maki; Sukegawa, Kota*; Tai, R.; Mesesson, S.*; Tanaka, Momoko; Lu, P.; Kawachi, Tetsuya; Nagashima, Keisuke; et al.
Japanese Journal of Applied Physics, 42(2A), p.443 - 448, 2003/02
Times Cited Count:14 Percentile:50.33(Physics, Applied)no abstracts in English
Koike, Masato; Sano, Kazuo*; Yoda, Osamu; Harada, Yoshihisa*; Ishino, Masahiko; Moriya, Naoji*; Sasai, Hiroyuki*; Takenaka, Hisataka*; Gullikson, E. M.*; Mrowka, S.*; et al.
Review of Scientific Instruments, 73(3), p.1541 - 1544, 2002/03
Times Cited Count:20 Percentile:68.25(Instruments & Instrumentation)no abstracts in English
Koike, Masato; Ishino, Masahiko; Sano, Kazuo*; Takenaka, Hisataka*; Hatayama, Masatoshi*; Sasai, Hiroyuki*; Heimann, P. A.*; Gullikson, E. M.*
no journal, ,
no abstracts in English
Koike, Masato; Ishino, Masahiko; Sano, Kazuo*; Takenaka, Hisataka*; Hatayama, Masatoshi*; Heimann, P. A.*; Gullikson, E. M.*; Sasai, Hiroyuki*
no journal, ,
no abstracts in English
Ishino, Masahiko; Koike, Masato; Heimann, P. A.*; Sasai, Hiroyuki*; Hatayama, Masatoshi*; Takenaka, Hisataka*; Sano, Kazuo*; Gullikson, E. M.*
no journal, ,
no abstracts in English