Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Ito, Chikara
no journal, ,
no abstracts in English
using laser-induced breakdown spectroscopy (LIBS)Oba, Hironori; Saeki, Morihisa; Ito, Chikara; Takano, Masahide; Akaoka, Katsuaki; Thornton, B.*; Sakka, Tetsuo*; Wakaida, Ikuo
no journal, ,
In the post-accident nuclear core reactor of the TEPCO Fukushima Daiichi Nuclear Power Plants, melted fuel core, fuel cladding and construction material (corium debris) might drop in the lower part of the reactor, which filled with seawater that was injected for urgent cooling. The major components of the debris material are assumed to be uranium oxide (UO, fuel core), zirconium alloy (Zry, fuel cladding) and iron (Fe, construction material). In this presentation, we report underwater analysis of simulated corium debris, (U,Zr)O, by the transportable fiber-coupled LIBS instrument. The experiments were carried out using a wavelength region of 730-1100 nm for pulsed-lasers and plasma emission measurements, which shows no attenuation in the optical transmittance of the fiber optic cable by intense radiation dose. Based on the observed emission spectrum in the region of 750-870 nm, we determined candidates of the emission lines of Zr, U and Fe that are applicable to analyses of the debris without mutual interference. The LIBS spectra of five different concentration ratio samples for Zr/U were measured to obtain calibration data. We succeeded to obtain linear calibration data for emission intensity ratio versus concentration ratio of Zr/U.
Wakaida, Ikuo; Akaoka, Katsuaki; Miyabe, Masabumi; Kato, Masaaki; Otobe, Haruyoshi; Oba, Hironori; Khumaeni, A.
no journal, ,
In Japan Atomic Energy Agency (JAEA), research and development of quick analysis for next-generation MOX fuel without chemical analysis and neutron measurement had been carried out as the entrusted project by MEXT, and basic performances by using un-irradiated MOX fuel were demonstrated. In elemental analysis by Laser Induced Breakdown Spectroscopy (LIBS) with high resolution spectrometer, relative error of 2.9% at 30% Pu and the detection lower limit of 2,500 ppm in U oxide were demonstrated with the operation time of 5 min.. In isotope ratio analysis by Ablation Resonance Absorption Spectroscopy, tunable semiconductor laser system was constructed, and the relative deviation less than 1% in the ratio of 
Pu/
Pu and sensitivity of 30-100 ppm in U were also accomplished within 5min. operation. As for an analysis in liquid sample, ultra-thin laminate flow was experimented as LIBS target, and the sensitivity comparable to conventional ICP-AES was confirmed.
Wakaida, Ikuo; Akaoka, Katsuaki; Miyabe, Masabumi; Khumaeni, A.; Oba, Hironori; Ito, Chikara
no journal, ,
In the new concept of next generation nuclear fuel cycle for long lived radioactive waste disposal by use of Accelerator Driven Subcritical reactor (ADS Cycle) and by a fast breeder reactor (FBR Cycle), utilization of low-decontaminated fuel with TRU will be promoted. Simultaneous analysis of element and isotope by the combination of Laser Induced Breakdown Spectroscopy (LIBS) and Ablation Resonance Absorption Spectroscopy was demonstrated by MOX fuel. For elemental analysis, detection lower limit of 1000 ppm of Pu in U oxide and relative error under 5% have been obtained within 5 min. For isotope analysis, Pu and Pu have been observed separately, and detection lower limit of several 10 ppm and error under 1% have been accomplished. A simple antenna coupled microwave assisted LIBS was performed and the enhancement of emission intensity of several 10 times was demonstrated. For liquid sample, ultra-thin laminate flow as the laser focused target was accomplished high sensitivity of ppb. For in-situ monitoring, Optical Fiber LIBS Probe by radiation resistant optical fiber is under construction.
Oba, Hironori; Saeki, Morihisa; Ito, Chikara; Takano, Masahide; Akaoka, Katsuaki; Wakaida, Ikuo; Sakka, Tetsuo*; Thornton, B.*
no journal, ,
In order to inspect the post-accident nuclear core reactor of the TEPCO Fukushima Daiichi Nuclear Power Plants, a transportable fiber-coupled laser-induced breakdown spectroscopy (LIBS) instrument has been developed. In this presentation, we report underwater analysis of simulated corium debris, (U,Zr)O, by the transportable fiber-coupled LIBS instrument. The experiments were carried out using a wavelength region of 730
1100 nm for pulsed-lasers and plasma emission measurements, which shows no attenuation in the optical transmittance of the fiber optic cable by intense radiation dose. Based on the observed emission spectrum in the region of 750870 nm, we determined candidates of the emission lines of Zr, U and Fe that are applicable to analyses of the debris without mutual interference.
Wakaida, Ikuo; Oba, Hironori; Akaoka, Katsuaki; Oba, Masaki; Ruas, A.; Saeki, Morihisa; Miyabe, Masabumi; Ikeda, Yuji*; Sakka, Tetsuo*
no journal, ,
no abstracts in English
Matsumoto, Ayumu; Oba, Hironori; Toshimitsu, Masaaki; Akaoka, Katsuaki; Wakaida, Ikuo
no journal, ,
no abstracts in English
Wakaida, Ikuo
no journal, ,
no abstracts in English
Matsumoto, Ayumu; Oba, Hironori; Toshimitsu, Masaaki; Akaoka, Katsuaki; Wakaida, Ikuo
no journal, ,
no abstracts in English
Kawakami, Tomohiko*; Nakano, Natsuko*; Takagi, Kazunari*; Spaziani, F.*; Hanamoto, Yukio*; Abe, Yuta
no journal, ,
no abstracts in English
Matsumoto, Ayumu; Oba, Hironori; Toshimitsu, Masaaki; Akaoka, Katsuaki; Wakaida, Ikuo
no journal, ,
no abstracts in English
Kawakami, Tomohiko*; Abe, Yuta; Spaziani, F.*; Nakano, Natsuko*; Nakagiri, Toshio
no journal, ,
no abstracts in English
Matsumoto, Ayumu; Oba, Hironori; Akaoka, Katsuaki; Wakaida, Ikuo
no journal, ,
no abstracts in English
Okazaki, Kodai*; Abe, Yuta; Spaziani, F.*; Nakano, Natsuko*; Kawakami, Tomohiko*
no journal, ,
no abstracts in English
Abe, Yuta; Yamashita, Takuya; Kawakami, Tomohiko*
no journal, ,
no abstracts in English
Okazaki, Kodai*; Kawakami, Tomohiko*; Abe, Yuta; Otaka, Masahiko
no journal, ,
no abstracts in English
Wakaida, Ikuo; Sakka, Tetsuo*; Ikeda, Yuji*; Oba, Hironori*; Taira, Takunori*
no journal, ,
no abstracts in English
Abe, Yuta; Otaka, Masahiko; Okazaki, Kodai*; Kawakami, Tomohiko*; Oishi, Yuji*
no journal, ,
no abstracts in English
Okazaki, Kodai*; Kawakami, Tomohiko*; Abe, Yuta; Otaka, Masahiko; Oishi, Yuji*
no journal, ,
no abstracts in English
Makuuchi, Etsuyo*; Nagayama, Sakiko*; Abe, Yuta; Okazaki, Kodai*; Kawakami, Tomohiko*; Oishi, Yuji*; Otaka, Masahiko
no journal, ,
no abstracts in English