Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Zhang, X. Z.*; Esaka, Fumitaka; Esaka, Konomi; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu; Watanabe, Kazuo
Spectrochimica Acta, Part B, 62(10), p.1130 - 1134, 2007/10
Times Cited Count：23 Percentile：70.33(Spectroscopy)The capability of inductively coupled plasma mass spectrometry (ICP-MS) for the determination of uranium isotope ratios in individual particles was determined. For this purpose, we developed an experimental procedure including single particle transfer with a manipulator, chemical dissolution and isotope ratio analysis. As the result, the 
U/
U isotope ratio for the particle with the diameter between 0.5 and 3.9 
m was successfully determined with the deviation from the certified ratio within 1.8%. The developed procedure was successfully applied to the analysis of a simulated environmental sample prepared from a mixture of indoor dust (NIST SRM 2583) and uranium particles (NBL CRM U050, U350 and U950a). From the results, the proposed procedure was found to be an alternative analytical tool for nuclear safeguards.
Shinonaga, Taeko*; Donohue, D.*; Klose, D.*; Kuno, Takehiko*; Kuno, Yusuke*; Esaka, Fumitaka; Esaka, Konomi; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu
STI/PUB/1298 (CD-ROM), p.525 - 531, 2007/08
More precise, accurate and prompt analyses of uranium and plutonium in various types of environmental samples are increasingly requested from the Clean Laboratory Unit, Safeguards Analytical Laboratory of IAEA in recent years. Particles show unique information and up to now, the secondary ion mass spectrometry (SIMS) has been employed for the uranium and plutonium particle analysis. The SIMS that is the most rapid method for particle analysis has, however, disadvantages for the analysis of the minor isotopes like 
U and 
U, i.e., not precise enough. The SIMS measurement also has a difficulty on Pu determination because of the interference of U-based isobaric signals. In this study, a combination of techniques, picking-up particles by a manipulator attached to a scanning electron microscope (SEM), followed by uranium and plutonium chemical purification and measurement by an inductively coupled plasma mass spectrometer (ICP-MS) and thermal ionization mass spectrometer (TIMS), was demonstrated for particle analysis using standard materials (NBS U500 and NBS 947) to develop a particle-chemical analysis.
Esaka, Fumitaka; Esaka, Konomi; Lee, C. G.; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu; Watanabe, Kazuo
Talanta, 71(3), p.1011 - 1015, 2007/02
Times Cited Count：63 Percentile：87.33(Chemistry, Analytical)A new technique to measure U/U and U/U isotope ratios for individual particles in safeguards environmental samples was developed, which was a combination of particle isolation under scanning electron microscope (SEM) and secondary ion mass spectrometry (SIMS). In order to verify the effectiveness of the technique, the U/U and U/U isotope ratios were measured for individual particles in a simulated environmental sample containing uranium standard (NIST CRM U010) and Pb metal particles. The deviations of the U/U and U/U isotope ratios from the certified values increased with increasing the signal intensity ratio of 
Pb to U, which was due to the interferences by Pb molecular ions. By the isolation of individual uranium particles prior to SIMS analysis, the interferences were eliminated. The effectiveness of the technique was also confirmed by the analysis of a real sample taken at a laboratory in Japan Atomic Energy Agency (JAEA).
Esaka, Fumitaka; Esaka, Konomi; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu; Watanabe, Kazuo
Nuclear Instruments and Methods in Physics Research B, 251(1), p.218 - 222, 2006/09
Times Cited Count：3 Percentile：21.09(Instruments & Instrumentation)Individual Cu particles were transferred, with a manipulator attached to a scanning electron microscope, onto individual Si carriers for subsequent quantitative analysis by means of total-reflection X-ray fluorescence spectrometry. By applying an internal standard to the carriers prior to the particle transfer, the amounts of Cu were successfully determined for the particles with diameters between 3.04 and 8.84 micrometer. The deviations of the measured values from the calculated ones were within 10%. However, the deviations were more than 33% if particle diameters were greater than 10.17 micrometer. This suggests that in such a case the fluorescent X-ray is not emitted from all parts of the particle. Even if particle diameters were greater than 10.17 micrometer, the amounts of Cu could be determined with the deviations within 9% when the particles were dissolved with HNO
solution. This technique was also successfully applied to the measurement of individual brass particles.
Usuda, Shigekazu; Yasuda, Kenichiro; Kokubu, Yoko; Esaka, Fumitaka; Lee, C. G.; Magara, Masaaki; Sakurai, Satoshi; Watanabe, Kazuo; Hirayama, Fumio; Fukuyama, Hiroyasu; et al.
International Journal of Environmental Analytical Chemistry, 86(9), p.663 - 675, 2006/08
Times Cited Count：14 Percentile：40.18(Chemistry, Analytical)The IAEA introduced the environmental sample analysis method, as a powerful tool to detect undeclared nuclear activities, into strengthened safeguards system. The principle of the method is that nuclear signatures can be evidenced if trace amount of nuclear materials in environmental samples taken from inside and outside of nuclear facilities are accurately analyzed. Currently, isotope ratios of uranium and plutonium in "swipe" samples are measured, which are collected in nuclear facilities. In future, the subject of environmental sample analysis will expand to soil, sediment, vegetation, water and airborne dust taken from outside of the nuclear facilities. If physical and chemical form of the nuclear materials is identified, we may estimate their origin, treatment process and migration behavior. This paper deals with the developed analytical techniques for the safeguards environmental samples, the current R&D on techniques related to estimation of the physical and chemical form, and possible analytical methodologies applicable to ultra-trace amounts of nuclear materials.
Iguchi, Kazunari; Esaka, Konomi; Lee, C. G.; Inagawa, Jun; Esaka, Fumitaka; Onodera, Takashi; Fukuyama, Hiroyasu; Suzuki, Daisuke; Sakurai, Satoshi; Watanabe, Kazuo; et al.
Radiation Measurements, 40(2-6), p.363 - 366, 2005/11
Times Cited Count：11 Percentile：59.93(Nuclear Science & Technology)In particle analysis for safeguards environmental samples, the fission track technique is very important to detect sub-micrometer particles containing uranium. In the technique the authors developed, the particles were recovered onto the polycarbonate membrane filter. The filter was dissolved in solvent and dried to form a thin film of detector, in which the particles were confined. After thermal neutron irradiation and etching, the particles of interest in the detector were easily identified with fission tracks, and were picked up for isotope ratio analysis. It was found, however, that the particles in the vicinity of the detector surface may fall off during the etching process. Therefore, optimization of the etching condition is required. In this work, the effects of etching time and enrichment of uranium in particles were investigated. Preliminary results suggest that etching time should be shorter with the increase in the enrichment.
Sakurai, Satoshi; Magara, Masaaki; Usuda, Shigekazu; Watanabe, Kazuo; Esaka, Fumitaka; Hirayama, Fumio; Lee, C. G.; Yasuda, Kenichiro; Kono, Nobuaki; Inagawa, Jun; et al.
Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10
no abstracts in English
Magara, Masaaki; Usuda, Shigekazu; Sakurai, Satoshi; Watanabe, Kazuo; Esaka, Fumitaka; Hirayama, Fumio; Lee, C. G.; Yasuda, Kenichiro; Kono, Nobuaki; Inagawa, Jun; et al.
Dai-26-Kai Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Nenji Taikai Rombunshu, p.157 - 164, 2005/00
JAERI has conducted the analysis of domestic and the IAEA samples. JAERI is developing the analytical techniques to improve the analytical ability for the safeguards environmental samples. For bulk analysis, study is focused on the improvement of reliability of isotope ratio measurements by ICP-MS. New chemical separation techniques are under development and a desolvation module is introduced to reduce the polyatomic interferences. In particle analysis, the sample preparation procedure for SIMS method is modified to measure the U/U and U/U ratios for individual particles. We are also developing fission track-TIMS method to measure uranium isotope ratios in particles of sub-micrometer size. A screening instrument of X-ray fluorescent analysis is equipped to measure elemental distribution on a swipe surface.
Magara, Masaaki; Usuda, Shigekazu; Sakurai, Satoshi; Watanabe, Kazuo; Esaka, Fumitaka; Hirayama, Fumio; Lee, C. G.; Yasuda, Kenichiro; Kono, Nobuaki; Inagawa, Jun; et al.
Proceedings of INMM 46th Annual Meeting (CD-ROM), 8 Pages, 2005/00
JAERI has been developing analytical techniques for ultra-trace amounts of nuclear materials in the environmental samples in order to contribute to the strengthened safeguards system. Development of essential techniques for bulk and particle analysis of the environmental swipe sample has been established as an ultra-trace analytical method of uranium and plutonium. In January 2003, JAERI was qualified as a member of the IAEA network analytical laboratories for environmental samples. Since then, JAERI has conducted the analysis of domestic and the IAEA samples. From Japanese fiscal year 2003, the second phase of the project was started for the development of advanced techniques, such as analyzing minor actinides and fission products as well as uranium and plutonium, particle analysis using fission-track technique, more efficient particle analysis using ICP-TOFMS and screening by X-ray fluorescent analysis. This paper deals with the progress in the development of the new techniques, applications and future perspective.
Esaka, Fumitaka; Watanabe, Kazuo; Fukuyama, Hiroyasu; Onodera, Takashi; Esaka, Konomi; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu
Journal of Nuclear Science and Technology, 41(11), p.1027 - 1032, 2004/11
Times Cited Count：60 Percentile：95.56(Nuclear Science & Technology)A new particle recovery method and a sensitive screening method were developed for subsequent isotope ratio analysis of uranium particles in safeguards swipe samples. The particles in the swipe sample were recovered onto a carrier by means of vacuum suction 8211; impact collection method. When grease coating was applied to the carrier, the recovery efficiency was improved to 48 %, which is superior to that of conventionally-used ultrasoneration method. Prior to isotope ratio analysis with secondary ion mass spectrometry (SIMS), total reflection X-ray fluorescence spectrometry (TXRF) was applied to screen the sample for the presence of uranium particles. By the use of Si carriers in TXRF analysis, the detection limit of 22 pg was achieved for uranium. By combining these methods with SIMS, the isotope ratios of U/U for individual uranium particles were efficiently determined.
Lee, C. G.; Iguchi, Kazunari; Esaka, Konomi; Magara, Masaaki; Esaka, Fumitaka; Sakurai, Satoshi; Watanabe, Kazuo; Usuda, Shigekazu
Analytica Chimica Acta, 517(1-2), p.215 - 220, 2004/07
Times Cited Count：4 Percentile：13.8(Chemistry, Analytical)In this study, we discussed the feasibility of solid sample ETV-ICP-MS for the particle analysis of the environmental swipe samples in order to establish the fission track-ETV-ICP-MS method. Samples used were solid samples containing Tl, Pb and U in polycarbonate film, and their standard solutions. The analytical performance will be reported in terms of the optimization of temperature program, and sensitivity and precision in isotope ratio measurement.
Esaka, Konomi; Esaka, Fumitaka; Inagawa, Jun; Iguchi, Kazunari; Lee, C. G.; Sakurai, Satoshi; Watanabe, Kazuo; Usuda, Shigekazu
Japanese Journal of Applied Physics, Part 2, 43(7A), p.L915 - L916, 2004/07
Times Cited Count：41 Percentile：78.95(Physics, Applied)An effective method for isotope ratio analysis of individual particles containing uranium in safeguards swipe samples was developed by using a fission track (FT) technique combined with thermal ionization mass spectrometry (TIMS). The particles in the sample were directly recovered onto a polycarbonate membrane filter, which was set in a filtration system. After the particle recovery, the filter was dissolved to form a non-coated FT detector film containing the particles. Individual particles containing uranium were then identified by the observation of fission tracks created by thermal neutron irradiation. By combination of the FT technique with TIMS, isotope ratios of uranium for individual particles in the swipe sample prepared from a uranium standard reference material could be effectively determined.
Esaka, Fumitaka; Watanabe, Kazuo; Fukuyama, Hiroyasu; Onodera, Takashi; Esaka, Konomi; Inagawa, Jun; Iguchi, Kazunari; Suzuki, Daisuke; Lee, C. G.; Magara, Masaaki; et al.
Dai-25-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu, p.128 - 135, 2004/00
Japan Atomic Energy Research Institute (JAERI) was qualified as a member of the IAEA network analytical laboratories (NWALs) for particle and bulk analyses of safeguards environmental samples in January 2003. The particle analysis gives more detailed information on nuclear facility operation than the bulk analysis because the isotope ratios of nuclear materials in the samples collected inside nuclear facilities (swipe samples) can be determined for individual particles. We applied, as a method for uranium isotope ratio measurement, secondary ion mass spectrometry (SIMS) to particle analysis. Prior to the SIMS analysis, the particles in a swipe sample are recovered onto a carrier by impaction. The carriers with the recovered particles are then screened by total reflection X-ray fluorescence spectrometry. We integrated these techniques into a standard procedure, which is applied to domestic and IAEA swipe samples routinely.
Takahashi, Masato; Magara, Masaaki; Sakurai, Satoshi; Kurosawa, Setsumi; Esaka, Fumitaka; Taguchi, Takuji; Takai, Konomi; Fukuyama, Hiroyasu; Lee, C. G.; Yasuda, Kenichiro; et al.
Dai-23-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu, 8 Pages, 2002/09
Based on the strengthen safeguard program of the IAEA to detect undeclared nuclear activities, the method of precise and accurate isotope ratio determination for uranium and plutonium in the environmental samples (cotton swipes) has been developed at JAERI. The samples should be treated in clean environment in order to secure the analytical reliability by eliminating external contamination from the samples containing trace amount of uranium and plutonium. Since the measurement by ICP-MS is favorable to bulk analysis from view points of analytical capacity and operation simplicity, we have studied sample preparation procedures for the trace amount of uranium and plutonium to be applied to ICP-MS. Up to the present, interfering factors involved during analytical processes and the ICP-MS measurement of uranium and plutonium were examined. As a result, uranium and plutonium isotope measurement more than 100 pg and 100 fg, respectively, became possible at JAERI clean facility. At presentation, other progress in the development will be reported.
Esaka, Fumitaka; Magara, Masaaki; Hanzawa, Yukiko; Sakurai, Satoshi; Taguchi, Takuji; Takai, Konomi; Sakakibara, Takaaki; Kurosawa, Setsumi; Takahashi, Masato; Yasuda, Kenichiro; et al.
Dai-22-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu, 8 Pages, 2001/11
no abstracts in English
Iguchi, Kazunari; Lee, C. G.; Inagawa, Jun; Suzuki, Daisuke; Esaka, Fumitaka; Esaka, Konomi; Fukuyama, Hiroyasu; Onodera, Takashi; Magara, Masaaki; Watanabe, Kazuo; et al.
no journal, ,
no abstracts in English
Esaka, Konomi; Yasuda, Kenichiro; Esaka, Fumitaka; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu; Nakayama, Shinichi
no journal, ,
no abstracts in English
Esaka, Fumitaka; Esaka, Konomi; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu; Watanabe, Kazuo
no journal, ,
no abstracts in English
