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Wakaida, Ikuo; Akaoka, Katsuaki; Oba, Masaki; Maruyama, Yoichiro; Miyabe, Masabumi; Otobe, Haruyoshi; Niki, Hideaki*
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-30-Kai Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2010/01
In Japan Atomic Energy Agency, basic study on remote analysis by combination of LIBS for impurity measurement and AIRAS for isotope measurement is performed to apply rapid and on-site analysis of next generation fuel. For the impurity measurement of the sample with the matrix of Lanthanide or Uranium oxide which has complex spectrum structure, detection linearity to % order and the detection limit of order 100 ppm are obtained by the optimization of the measurement conditions of the delay time, gas pressure and by the deconvolution of the spectrum. For the isotope analysis, the laser system specialized for the resonance spectroscopy by frequency stabilized semiconductor tunable laser has been developed. And under the low pressure rare gas condition, spectrum resolution of 800 MHz is measured and the detection of 
U in Natural Uranium is realized.
Mukai, Yasunobu; Koiso, Katsuya; Nakamura, Hironobu; Hosoma, Takashi; Yoshimoto, Katsunobu; Hayashi, Hiroyuki*
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-30-Kai Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2009/11
Electro manometer (ELTM) is a device to measure accurately level, density and volume in an accountability tank for the purpose of nuclear materials accountancy, safeguards and operational control. JAEA have developed and put the ELTM using digiquartz differential pressure transducer into practical use at plutonium conversion development facility since initial tank calibration in 1982. As a result of calibrations and measurements in the last 15 years, the sustainable measurement accuracy is 
2 Pa as a sigma of difference from the standard pressure and 0.002 g/cm
as a sigma of difference from the solution density analytically determined. However, a drift of data we have never experienced was found in 2008. After investigations, a characteristic value T
(period of vibration at zero pressure) which is stable in normal state had changed around 7% at the drift. This was the result of aging, so it was found that monitoring of T value was the very effective information to know the timing of replacement of the transducer. We will present the long-term measurement accuracy of ELTM practically achieved and the way of maintenance including a replacement of the transducer.
Wakabayashi, Shuji; Kobayashi, Naoki*; Naoi, Yosuke; Tazaki, Makiko; Senzaki, Masao
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-30-Kai Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2009/11
The assurance of supply (AOS) of nuclear fuel is a special arrangement in case of supply disruptions caused by political reasons other than nonproliferation. It aims to support the stable supply of nuclear fuel while avoiding the unnecessary spread of sensitive enrichment technology. Current discussions on AOS have been initiated by the IAEA Director-General's article. Since then, various proposals on the AOS have been presented for discussion, such as USA's 17.4t HEU down-blended to LEU Reserve proposal, NTI proposal, Japan's IAEA Standby Arrangements System proposal, Russian's International Uranium Enrichment Center proposal. In order to facilitate the international discussion of the assurance of supply system, we focused and based our study on Japanese proposal. We have been able to show the feasibility of AOS system more specifically by supposing additional costs and the required period necessary for the AOS and present a system we made that we hope as a practical system.
Nakamura, Hironobu; Takaya, Akikazu; Mukai, Yasunobu; Hosoma, Takashi; Yoshimoto, Katsunobu; Tamura, Takayuki*; Iwamoto, Tomonori*
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-30-Kai Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2009/11
JNFL and JAEA have collaboratively started to develop an ASMS for RRP since 2007. The purpose of the development is to establish direct plutonium mass measurement technique by NDA of high concentrated pure plutonium nitrate solution in a strategic process tank. If it is established, ASMS provides direct Pu mass measurement and monitoring capability, substitutes for sampling and destructive analysis at IIV, and extends process monitoring to safety purposes. The target of the measurement uncertainty is set less than 6% which is equivalent to the detection level of partial defect at IIV by NDA. The principle is similar to the one of NDA for MOX powder, but extended such as introducing variable alpha depends on solution properties. As a first trial, a simple prototype system was constructed and calibrated at PCDF (Plutonium Conversion Development Facility) using plutonium nitrate solution. Consequently, good consistency between MCNP (Monte Carlo Neutron and Photon Transport Code) calculation and measured singles/doubles count rate were obtained. As a feasibility study, it was necessary to find out subjects to be solved. We would like to present benefits of ASMS, review installation and detector setup and summarize preliminary calibration results.
Katsumura, Soichiro; Seya, Michio; Wakaida, Ikuo
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-30-Kai Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2009/11
In next generation fuel fabrication facilities, low decontaminated MOX (Mixed Oxide Fuel) with MA (minor actinide) including 
Cm is going to be treated. In case of the low decontaminated MOX with MA, if Cm is included more than 0.01% of 
Pu, the amount of neutron generation from spontaneous fissions of Cm exceed that of Pu. This is because that Cm produces near 10
times higher than Pu. And also determination of Pu isotopic composition by 
-ray spectroscopy seems to be less-accurate or impossible, because of high back ground -rays generated by bremsstrahlung of beta-decay electrons from FPs in the low decontaminated MOX. In this presentation, the future issues of the verification of the low decontaminated MOX with MA are shown, and as one of possible verification approach, application of LIBS (Laser Induced Breakdown Spectroscopy) + AIRAS (Ablation Initiated Resonance Absorption Spectroscopy) is explained.