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Masuda, Ryo; Mitsui, Takaya; Kobayashi, Yasuhiro*; Higashitaniguchi, Satoshi*; Seto, Makoto
Japanese Journal of Applied Physics, 48(12), p.120221_1 - 120221_3, 2009/12
Times Cited Count:9 Percentile:35.73(Physics, Applied)A neV-resolution spectrometer using 14.4 keV synchrotron-based Fe M
ssbauer radiation has been developed to observe the quasi-elastic scattering by condensed matter. It consists of a
Fe
O
nuclear resonant Bragg monochromator and a
Fe stainless steel nuclear analyzer. As a feasibility study, the quasi-elastic scattering by supercooled glycerol near its melting point has been observed. The instrumental function of the spectrometer was 42.2 neV. The energy broadening of 11 neV due to the quasi-elastic scattering was observed.
Seto, Makoto; Masuda, Ryo; Higashitaniguchi, Satoshi*; Kitao, Shinji*; Kobayashi, Yasuhiro*; Inaba, Chika*; Mitsui, Takaya; Yoda, Yoshitaka*
Physical Review Letters, 102(21), p.217602_1 - 217602_4, 2009/05
Times Cited Count:58 Percentile:87.76(Physics, Multidisciplinary)We have developed a new method that yields Mssbauer absorption spectra using synchrotron radiation (SR); this method is applicable for almost all M
ssbauer nuclides including those that cannot be measured by previous methods using radioisotope (RI) sources. The M
ssbauer spectrum of the 68.752 keV excited state of
Ge, which cannot be measured using a RI source, was measured using SR. Our results show that this method can be used to perform advanced M
ssbauer spectroscopy measurements owing to the excellent features of SR.
Masuda, Ryo; Mitsui, Takaya; Kitao, Shinji*; Higashitaniguchi, Satoshi*; Yoda, Yoshitaka*; Seto, Makoto
Japanese Journal of Applied Physics, 47(10), p.8087 - 8090, 2008/10
Times Cited Count:13 Percentile:46.13(Physics, Applied)A synchrotron-radiation-based neV-resolution spectrometer has been developed using single-line pure nuclear Bragg reflection. The developed optical system consists of two components: a FeBO
single crystal near the N
el temperature for producing
Fe M
ssbauer radiation from synchrotron radiation, and a single-line M
ssbauer absorber (
Fe-enriched stainless steel foil) for analyzing the energy distribution. As a feasibility study, we have performed the measurement of the M
ssbauer radiation diffracted by a Si crystal under ultrasound vibration with the optical system and have successfully observed the neV-range energy modulation due to the ultrasound vibration.
Mitsui, Takaya; Seto, Makoto; Hirao, Naohisa*; Oishi, Yasuo*; Kobayashi, Yasuhiro*; Higashitaniguchi, Satoshi*; Masuda, Ryo*
Japanese Journal of Applied Physics, Part 2, 46(16), p.L382 - L384, 2007/04
Times Cited Count:12 Percentile:43.75(Physics, Applied)Energy-domain synchrotron radiation Mssbauer spectroscopy was performed by a single-line M
ssbauer filtering technique and focusing X-ray optics. Pure nuclear Bragg reflection from a heated
FeBO
single crystal was used for a neV order bandwidth ultrahigh energy resolution X-ray analyzer. As an example of small target research, the M
ssbauer transmission spectrum of polycrystalline iron metal was observed using a diamond anvil cell at multimegabar pressures (252 GPa) for the first time.
Mitsui, Takaya; Seto, Makoto; Kikuta, Seishi*; Hirao, Naohisa*; Oishi, Yasuo*; Takei, Fumihiko*; Kobayashi, Yasuhiro*; Kitao, Shinji*; Higashitaniguchi, Satoshi*; Masuda, Ryo*
Japanese Journal of Applied Physics, Part 1, 46(2), p.821 - 825, 2007/02
Times Cited Count:34 Percentile:74.39(Physics, Applied)Ultrahigh monochromatic 14.4 keV X-rays with a narrow bandwidth of 15.4 neV were generated successfully with a high counting rate of 12,000 counts/s at the undulator beamline (BL11XU) of SPring-8. It was achieved by combining an intense X-ray from the third generation synchrotron radiation facility SPring-8 and pure nuclear Bragg scattering of a very highquality FeBO
perfect single crystal at the N
el temperature. We describe the detailed study of the beam characteristics and some performance test experiments of energy-domain synchrotron radiation M
ssbauer spectroscopy, including a highpressure experiment using a diamond anvil cel.
Imai, Yasuhiko*; Yoda, Yoshitaka*; Kitao, Shinji*; Masuda, Ryo; Higashitaniguchi, Satoshi*; Inaba, Chika*; Seto, Makoto
Advances in X-ray/EUV Optics and Components II (Proceedings of SPIE Vol.6705), p.670512_1 - 670512_7, 2007/00
We have developed a high-resolution monochromator (HRM) for the measurement of nuclear resonant scattering of synchrotron radiation by Te at 35.49 keV using the backscattering of sapphire (9 1 -10 68). The relative energy resolution of
is achieved, that is 7.5 meV in energy bandwidth. A new HRM has been desired at this energy region because of the low efficiency of usual Si HRMs. This HRM opens studies on element-specific dynamics and electronic state of substances containing
Te.
Masuda, Ryo*; Higashitaniguchi, Satoshi*; Kitao, Shinji*; Kobayashi, Yasuhiro*; Seto, Makoto*; Mitsui, Takaya; Yoda, Yoshitaka*; Haruki, Rie*; Kishimoto, Shunji*
Journal of the Physical Society of Japan, 75(9), p.094716_1 - 094716_4, 2006/09
Times Cited Count:2 Percentile:19.16(Physics, Multidisciplinary)no abstracts in English
Sakasai, Akira; Ishida, Shinichi; Matsukawa, Makoto; Akino, Noboru; Ando, Toshinari*; Arai, Takashi; Ezato, Koichiro; Hamada, Kazuya; Ichige, Hisashi; Isono, Takaaki; et al.
Nuclear Fusion, 44(2), p.329 - 334, 2004/02
Times Cited Count:7 Percentile:22.52(Physics, Fluids & Plasmas)no abstracts in English
Sakasai, Akira; Ishida, Shinichi; Matsukawa, Makoto; Akino, Noboru; Ando, Toshinari*; Arai, Takashi; Ezato, Koichiro; Hamada, Kazuya; Ichige, Hisashi; Isono, Takaaki; et al.
Nuclear Fusion, 44(2), p.329 - 334, 2004/02
no abstracts in English
Tokunaga, Tomochika*; Taniguchi, Makoto*; Shimada, Jun*; Zhang, J.*; Inaba, Kaoru; Saegusa, Hiromitsu; Iwatsuki, Teruki
JNC TY7400 2003-003, 142 Pages, 2003/05
One of the major concerns for the high-level radioactive waste disposal is the possibility of the radionuclides to reach biosphere by groundwater flow. Recent research results have shown that the fresh groundwater discharge from subsea formations are widespread phenomena, thus, it is necessary to evaluate the submarine groundwater discharge as possible pathways of contaminant discharge towards the biosphere. It is also important to unravel the groundwater flow and associated material transport at the coastal area and subsea formations. To better understand the groundwater flow processes and the submarine groundwater discharge, we have conducted the hydrological, hydrogeological, geochemical, and numerical modeling studies at the Kurobe alluvial fan and its offshore, Toyama Prefecture, Japan. In this report, the results of the following research activities are presented:1)Development and application of a method to detect the locations of the submarine groundwater discharge.2)Development and application of a method to collect uncontaminated groundwater samples from subesa formations.3)Measurements of submarine groundwater dischange fluxes by automated seepage meter.4)Hydrological and geochemical studies for groundwater flow at the coastal area.5)Geochemical studied to understand sources of fresh submarine groundwater discharge.6)Extamination of groundwater flow and submarine groundwater discharge using methane concentration and carbon isotope ratio.7)Numerical modeling studies for coastal groundwater flow system.
Masaki, Kei; Taniguchi, Masaki; Miyo, Yasuhiko; Sakurai, Shinji; Sato, Kazuyoshi; Ezato, Koichiro; Tamai, Hiroshi; Sakasai, Akira; Matsukawa, Makoto; Ishida, Shinichi; et al.
Fusion Engineering and Design, 61-62, p.171 - 176, 2002/11
Times Cited Count:19 Percentile:74.08(Nuclear Science & Technology)A flat carbon fiber composite tile mock-up with screw tubes, which have helical fins like a nut, was fabricated aiming at further improvement of the heat removal performance of the cost-effectively manufactured divertor target for JT-60SC (modified JT-60 as a superconducting coil tokamak). The heat removal performance of the mock-up was successfully demonstrated on the JAERI Electron Beam Irradiation Stand. The estimated heat transfer coefficient of the screw tube at the non-boiling region was roughly 3 times higher than that of the smooth tube. This corresponds to 1.5 times that of the swirl tube. A heat cycle test of 10 MW/m2 showed that the mock-up with the screw tubes could withstand for 1400 cycles. These results indicate that the divertor target plate with the flat carbon fiber composite tile and the screw tube can be a promising candidate for the JT-60SC divertor target.
Chijimatsu, Masakazu*; Taniguchi, Wataru; Suzuki, Hideaki*; Nishigaki, Makoto*
Doboku Gakkai Rombunshu, (687), p.9 - 25, 2001/09
None
Mitsui, Takaya; Seto, Makoto; Higashitaniguchi, Satoshi*
no journal, ,
no abstracts in English
Taniguchi, Naoki; Yamaguchi, Makoto*; Tateishi, Tsuyoshi*
no journal, ,
Carbon steel has been selected as a candidate material for overpacks for geological disposal of high-level radioactive waste (HLW), and corrosion assessment of carbon steel in geological disposal environment has been in progress. The -ray from HLW is possible to induce radiolysis and have an effect on the corrosion of overpack. The corrosion bahavior of carbon steel has been studied in sysnthetic seawater (SSW) under
-ray irradiation. In this study, the effect of
-ray dose rate on the corrosion was investigated. As the results, the corrosion rate increased with dose rate in simple SSW. On the other hand, no effect of dose rate on the corrosion rate was observed in the presence of buffer material.
Taniguchi, Naoki; Yamaguchi, Makoto; Naito, Morimasa; Tateishi, Tsuyoshi*
no journal, ,
Corrosion tests of carbon steel were performed to estimaste possible effect of groundwater radiolysis by radiation from vitrified waste on corrosion rate of carbon steel overpack in HLW repository. While average corrosion rates from weight loss increased by
radiation (dose rate : 30-50 Gy/h) in synthetic seawater, accompanying increased corrosion potential and cathodic current density possibly due to contribution of radiolytically generated oxidants such as hydrogen peroxide participated in cathodic reaction. On the other hand, no apparent effect of
radiation was observed for samples in compacted bentonite buffer. In addition, corrosion rates little affected by dry density of bentonite buffer. A plausible mechanism was considered to explain the absence of the
radiation.
Masuda, Ryo; Mitsui, Takaya; Kitao, Shinji*; Higashitaniguchi, Satoshi*; Yoda, Yoshitaka*; Seto, Makoto
no journal, ,
no abstracts in English
Taniguchi, Naoki; Yamaguchi, Makoto; Naito, Morimasa; Tateishi, Tsuyoshi*
no journal, ,
In order to clarify the effect of radiation on the corrosion of carbon steel overpack in HLW disposal environment, immersion test and electrochemical measurement were carried out using synthetic seawater at 80
C under
radiation of 45 gy/h. In simple seawater case, the corrosion potential became noble, and the amount of corrosion and cathodic current were increased by
radiation. On the other hand, little effect of
radiation on the corrosion behavior was observed in the presence of bentonite.