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Sasaki, Yuji; Tsubata, Yasuhiro; Kitatsuji, Yoshihiro; Sugo, Yumi; Shirasu, Noriko; Ikeda, Yasuhisa*; Kawasaki, Takeshi*; Suzuki, Tomoya*; Mimura, Hitoshi*; Usuda, Shigekazu*; et al.
JAEA-Research 2014-008, 220 Pages, 2014/06
JAEA-Research-2014-008.pdf:41.81MB
The researches on Development of mutual separation technology of minor actinides by the novel hydrophilic and lipophilic diamide compounds, entrusted to Japan Atomic Energy Agency by the Ministry of Education, Culture, Sports, Science and Technology of Japan, from 2010 to 2012 are summarized. This project was composed of three themes, those are (1) Development of total recovery of MA+Ln: basic researches for new extractant, DOODA, (2) Development of mutual separation of Am/Cm/Ln: basic researches of Ln-complex, solvent extraction, and extraction chromatography, and (3) Evaluation of separation technique: process simulation. For topic (1), we summarized the information on characteristic of DOODA extractant. For topic (2), we summarized the information on structures of Ln-complexes, solvent extraction and chromatography. For topic (3), we summarized the information on conditions of mixer-settler and evaluation of each fraction separated.
Miyamoto, Yutaka; Yasuda, Kenichiro; Magara, Masaaki; Kimura, Takaumi; Usuda, Shigekazu*
Proceedings in Radiochemistry, 1(1), p.209 - 212, 2011/09
Nano grams of U, Th, Pb and lanthanides in a geological reference rock were sequentially separated with a single anion-exchange column. Mixture of acetic acid, HCl and HNO
were used as the eluents for this separation. The recovery of these key elements was more than 95%, and there was no fractionation among the recoveries of each lanthanide element. Alkaline metals, alkaline earth metals and Fe were effectively eliminated from the key elements. By using this technique, it is possible to simplify the complicated traditional processes without any special ligands, columns and equipments.
Usuda, Shigekazu*; Magara, Masaaki; Esaka, Fumitaka; Yasuda, Kenichiro; Kokubu, Yoko; Lee, C. G.; Miyamoto, Yutaka; Suzuki, Daisuke; Inagawa, Jun; Sakurai, Satoshi; et al.
Journal of Nuclear and Radiochemical Sciences, 11(2), p.A5 - A9, 2011/01
In the analysis of IAEA safeguards environmental samples, isotope ratios of ultra-trace amounts of uranium and plutonium in samples taken from nuclear facilities are determined to detect undeclared nuclear materials and activities. In order to keep and enhance the reliability of the measurement results, validation of analytical methods and estimation of measurement uncertainty in such ultra-trace analysis should be properly done in accordance with worldwide standards. In this paper, the current activities on achievement of QA/QC (quality assurance and quality control) and estimation of measurement uncertainty in the ultra-trace analysis at a clean chemistry laboratory (CLEAR) of JAEA are reported.
Miyamoto, Yutaka; Yasuda, Kenichiro; Magara, Masaaki; Kimura, Takaumi; Usuda, Shigekazu*
Journal of Nuclear and Radiochemical Sciences, 10(2), p.7 - 12, 2009/12
With combination of a single anion-exchange column and mixed-media of CHCOOH and other acids (HCl and/or HNO), 50 ng of U, Th, Pb, and lanthanides were sequentially separated. All of the elements were recovered more than 95%, and the decontamination factor was more than 100. This separation technique reduces separation time and simplified the complicated traditional processes without any special reagents and equipments.
Lee, C. G.; Suzuki, Daisuke; Esaka, Fumitaka; Magara, Masaaki; Shinohara, Nobuo; Usuda, Shigekazu*
Journal of Nuclear Science and Technology, 46(8), p.809 - 813, 2009/08
A method to selectively detect uranium particles with higher 
U enrichment has been developed. The newly developed method involves three key components, (1) a two-step filtration system for particle recovery from swipe samples, (2) a system for controlling the etching time of fission track (FT) detector, (3) a system for comparing the FT morphologies and particle sizes. The method to screen uranium particles according to their enrichment is focused on detecting highly enriched uranium particles preferentially in various those recovered from swipe sample; this is one of the most important tasks involved in nuclear safeguards. In order to verify the effectiveness of the screening method developed, a mixture sample containing uranium particles with natural composition and those with 10% enrichment is used. It was shown that enrichment-based screening of uranium particles is possible by comparing the FT morphologies and particle sizes, in addition to controlling the etching time.
Esaka, Fumitaka; Magara, Masaaki; Lee, C. G.; Sakurai, Satoshi; Usuda, Shigekazu; Shinohara, Nobuo
Talanta, 78(1), p.290 - 294, 2009/04
Times Cited Count：34 Percentile：71.54(Chemistry, Analytical)The determination of uranium isotope ratios in individual particles is of great importance for nuclear safeguards. In the present study, an analytical technique by inductively coupled plasma mass spectrometry (ICP-MS) with a desolvation sample introduction system was applied to isotope ratio analysis of individual uranium particles. In ICP-MS analysis of individual uranium particles with diameters ranging from 0.6 to 4.2 
m in a standard reference material (NBL CRM U050), the use of the desolvation system for sample introduction improved the precision of 
U/
U and 
U/U isotope ratios. The performance of ICP-MS with desolvation was compared with that of a conventionally used method, i.e., secondary ion mass spectrometry (SIMS). The analysis of test swipe samples taken at nuclear facilities implied that the performance of ICP-MS with desolvation was superior to that of SIMS in a viewpoint of accuracy, because the problems of agglomeration of uranium particles and molecular ion interferences by other elements could be avoided. These results indicated that ICP-MS with desolvation has an enough ability to become an effective tool for nuclear safeguards.
Esaka, Fumitaka; Watanabe, Kazuo; Onodera, Takashi; Lee, C. G.; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu
Applied Surface Science, 255(4), p.1512 - 1515, 2008/12
Times Cited Count：9 Percentile：40.55(Chemistry, Physical)Isotope ratio analysis of individual uranium particles in environmental samples taken at nuclear facilities is one of the key techniques for nuclear safeguards. For accurate analysis, we developed a combined technique of single particle manipulation, which was carried out in scanning electron microscope (SEM), and SIMS. This technique gives information on particle size as well as isotope ratios for each particle. In the present study, the particle size dependence of the precision of uranium isotope ratio is investigated by using the SEM-SIMS technique. In the analysis of individual particles of a CRM U050 (5% enriched uranium) sample, even if the particle diameter was 0.5 m, the analysis with the precision of U/U isotope ratio within 5% was possible. In the presentation, the results obtained for the other uranium particles having different isotopic composition will also be presented.
Usuda, Shigekazu; Shinohara, Nobuo; Sakurai, Satoshi; Magara, Masaaki; Miyamoto, Yutaka; Esaka, Fumitaka; Yasuda, Kenichiro; Kokubu, Yoko; Hirayama, Fumio; Lee, C. G.; et al.
KEK Proceedings 2007-16, p.13 - 22, 2008/02
For the purpose of controlling and monitoring radiations and radioactive materials emitted from nuclear facilities to the environment and also evaluating their effects, various R&D on environmental radioactivity has been carried out at Japan Atomic Energy Agency (JAEA). Especially, for the abolition of nuclear weapons and for peaceful uses nuclear energy, ultra-trace analysis of environmental samples for safeguards and ultra-high sensitive monitoring of radionuclides for the CTBT verification, which have been scheduled in the middle of 1990s, have been promotted under the auspices of the Japanese Government at JAERI, the former of JAEA. In this presentation, the outline of R&D on environmental radioactivity for nuclear non-proliferation is introduced. In addition, applications of the developed techniques and future perspectives will be discussed.
Cs released from Nagasaki atomic bomb in sediment of Nishiyama reservoir at NagasakiKokubu, Yoko; Yasuda, Kenichiro; Magara, Masaaki; Miyamoto, Yutaka; Sakurai, Satoshi; Usuda, Shigekazu; Yamazaki, Hideo*; Yoshikawa, Shusaku*; Nagaoka, Shinji*; Mitamura, Muneki*; et al.
Journal of Environmental Radioactivity, 99(1), p.211 - 217, 2008/01
Times Cited Count：19 Percentile：40.5(Environmental Sciences)In a sediment core of Nishiyama reservoir at Nagasaki, depth profiles of 
Pu/
Pu ratio, 
Pu and Cs concentrations were determined. Sediments containing plutonium and Cs, which were fallout deposited immediately after a detonation of Nagasaki atomic bomb, were identified in the core. Observed below the sediments were macroscopic charcoals, providing evidence for initial deposit of the fallout. This is the first entire depositional records of plutonium and Cs released from the Nagasaki atomic bomb together with those from atmospheric nuclear tests.
Magara, Masaaki; Usuda, Shigekazu; Sakurai, Satoshi; Shinohara, Nobuo; Esaka, Fumitaka; Kokubu, Yoko; Suzuki, Daisuke; Yasuda, Kenichiro; Lee, C. G.; Inagawa, Jun; et al.
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-29-Kai Nenji Taikai Rombunshu (CD-ROM), 6 Pages, 2008/00
JAEA has been developing, under the auspices of the Ministry of Education, Culture, Sports, Science and Technology of Japan, analytical techniques for ultra-trace amounts of nuclear materials in the environmental samples in order to contribute to the strengthened safeguards system. In January 2003, JAEA was qualified as a member of the IAEA network analytical laboratories (NWAL) for environmental sample analysis. Since then, JAEA has conducted the analysis of domestic and the IAEA samples. Two techniques, bulk and particle analyses, are available for the environmental samples and the latter method generally provides more detailed information about history of nuclear materials in a facility. However, isotope ratios of uranium are measured in the particle analysis at present and it is wished to develop analytical method for isotope ratios of plutonium in individual particles. We commence the development of the plutonium particle analysis and the consideration of age-dating for plutonium particles through the atomic ratio of Pu-241 and Am-241.
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.
Sakurai, Satoshi; Magara, Masaaki; Esaka, Fumitaka; Hirayama, Fumio; Lee, C. G.; Yasuda, Kenichiro; Inagawa, Jun; Suzuki, Daisuke; Iguchi, Kazunari; Kokubu, Yoko; et al.
STI/PUB/1298 (CD-ROM), p.791 - 799, 2007/08
no abstracts in English
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.
Kokubu, Yoko; Yasuda, Kenichiro; Magara, Masaaki; Miyamoto, Yutaka; Sakurai, Satoshi; Usuda, Shigekazu; Yamazaki, Hideo*; Yoshikawa, Shusaku*
Journal of Radioanalytical and Nuclear Chemistry, 273(1), p.183 - 186, 2007/07
Times Cited Count：7 Percentile：47.34(Chemistry, Analytical)no abstracts in English
Lee, C. G.; Iguchi, Kazunari; Inagawa, Jun; Suzuki, Daisuke; Esaka, Fumitaka; Magara, Masaaki; Sakurai, Satoshi; Watanabe, Kazuo; Usuda, Shigekazu
Journal of Radioanalytical and Nuclear Chemistry, 272(2), p.299 - 302, 2007/05
Times Cited Count：47 Percentile：93.88(Chemistry, Analytical)no abstracts in English
U/U ratio for a trace amount of uranium: Search for an extinct radionuclide 
Cm in the early solar systemChai, J.; Miyamoto, Yutaka; Kokubu, Yoko; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu; Oura, Yasuji*; Ebihara, Mitsuru*
Journal of Radioanalytical and Nuclear Chemistry, 272(2), p.397 - 401, 2007/05
Times Cited Count：2 Percentile：18.73(Chemistry, Analytical)Cm is an important nuclide because it has the next-shortest half-life (1.6
10
yr) from 
Pu among the transuranic nuclides. The disintegration of Cm to U by three 
decays and two 
decays and the chemical fractionation between Cm and U during the formation of solid materials in early solar system lead to changes in the ratios of U to U. This variation may provide strict constraints on the time interval between the last r-process nucleosynthetic event and the formation of the solar system. It is important to develop a practical analysis protocol to determine the isotope ratio of trace uranium in geochemical and environment samples. As uranium is the least abundant element in our solar system, analytical techniques with high sensitivity and precision are required. In this study, a double focusing inductively coupled plasma mass spectory was applied to measure isotopic ratio of uranium. By one set data obtained from the EDTA phase of the Jilin meteorite sample, the upper limit of Cm in the early solar system was calculated and Cm/U 
0.003 was obtained.
Cs found in the surface soils of Nagasaki, JapanKokubu, Yoko; Yasuda, Kenichiro; Magara, Masaaki; Miyamoto, Yutaka; Sakurai, Satoshi; Usuda, Shigekazu; Yamazaki, Hideo*; Mitamura, Muneki*; Yoshikawa, Shusaku*
Journal of Geosciences, Osaka City University, 50, p.7 - 13, 2007/03
no abstracts in English
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).
Miyamoto, Yutaka; Saito, Yoko; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu
Journal of Radioanalytical and Nuclear Chemistry, 271(1), p.83 - 88, 2007/01
Times Cited Count：0 Percentile：0.01(Chemistry, Analytical)Airborne dust samples were collected with a high-volume sampler at a fixed point in JAERI-Tokai for three years. Recently at JAERI-Tokai, a number of pine trees to arrest sand shifting was cut down. We analyzed the variation in elemental composition of the dust collected before and after felling the trees. It found, from the two-dimentional plots of ratio of elemental concentration such as Sc/Na-Cl/Na ratios, almost all samples consisted of mixture of sea-salt and soil. There were some differences between the elemental composition of the dust collected before and after felling the trees.
Lee, C. G.; Iguchi, Kazunari; Esaka, Fumitaka; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu
Japanese Journal of Applied Physics, Part 2, 45(42), p.L1121 - L1123, 2006/11
Times Cited Count：4 Percentile：17.08(Physics, Applied)no abstracts in English
