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Kokubu, Yoko; Magara, Masaaki; Usuda, Shigekazu; Shinohara, Nobuo; Yamazaki, Hideo*; Yoshikawa, Shusaku*; Murakami, Akiko*; Tsujimoto, Akira*; Nagaoka, Shinji*
no journal, ,
Depth profiles of concentration of 
Pu and 
Pu/
Pu ratio in the cores collected from the center of the Nagasaki Bay were determined to find depositional records of plutonium released from Nagasaki atomic bomb and other nuclear tests. The ratio in sediment at the depth of about 50 cm was higher than that of the global stratospheric fallout, which might show that the plutonium has come from the nuclear tests carried out around the Marshall Islands. Deposition of plutonium from the Nagasaki atomic bomb will be also reported in the presentation.
Miyamoto, Yutaka; Yasuda, Kenichiro; Kokubu, Yoko; Magara, Masaaki; Usuda, Shigekazu
no journal, ,
The authors investigated separation scheme of trace amounts of U, Th, Pb and lanthanoids using an anion-exchange column to analyse the abundance and isotopic ratio of those elements in environmental samples. For reducing the procedural blank, the separation was carried out with an anion-exchange column and high-pure or easy-to-purified reagents (methanol, hydrochloric acid, nitric acid, acetic acid). The mixture, which consists of mainly acetic acid, was good eluants for this separation. Each objective elements was sequentially separated, and fully recovered from a mixture of ICP-MS standard solution.
Usuda, Shigekazu; Magara, Masaaki; Esaka, Fumitaka; Sakurai, Satoshi; Lee, C. G.; Yasuda, Kenichiro; Kokubu, Yoko; Suzuki, Daisuke; Shinohara, Nobuo; Murata, Fujio*
no journal, ,
JAEA (Japan Atomic Energy Agency) has been conducting the environmental sample analysis, which is one of the IAEA's safeguards measures. In the analysis, isotope ratios of ultra-trace amounts of nuclear materials (uranium and plutonium) in the samples taken from nuclear facilities are determined to detect "environmental signature" of undeclared nuclear materials and activities. In order to enhance the reliability of the measurement results, validation of analytical methods and estimation of uncertainty of measurement in such ultra-trace analysis are required at the level of worldwide standardization. In this presentation, the authors introduce the current activities and future perspectives of achievement of QA/QC (quality assurance and quality control) and the estimation of uncertainty as a member of the IAEA Network Analytical Laboratories for the environmental samples.
Pu/Pu isotope ratio by ICP-MSKokubu, Yoko
no journal, ,
This presentation is one of the invited talks at a special session of "Advances and future prospect of A-bomb researches" in the 2008 Annual Meeting of the Japan Society of Nuclear and Radiochemical Sciences. Alpha-ray spectrometry of Pu was mainly used to assess plutonium from Nagasaki atomic bomb in the previous studies. However it was difficult to discriminate the plutonium due to atomic explosion in Nagasaki from global fallout by analysis of the 
-ray spectrum. In this study, Pu/Pu ratio measured by ICP-MS was used to identify the source of Pu and distributions of the Pu in sediment and soils were reported. Depth profile of the Pu in a sediment core collected at Nishiyama reservoir, Nagasaki city was determined to obtain depositional record of the Pu from the atomic bomb for 60 years. The Pu was measured in surface soils collected around the hypocenter of the atomic bomb to identify geological distribution of the Pu from the atomic bomb.
Tsukada, Kazuaki; Kasamatsu, Yoshitaka; Asai, Masato; Toyoshima, Atsushi; Ishii, Yasuo; Nagame, Yuichiro
no journal, ,
Aqueous chemistry of element 105, dubnium, using a liquid-chromatography is now being performed at the JAEA tandem accelerator. The nuclide 34-s 
Db is produced in the 
Cm(
F, 5n) reaction with the production rate of about 0.25 atoms per min. To obtain more accurate data with high statistics, we need to develop a new device to shorten the time for the preparation of sources. Recently, a new apparatus based on a continuous sample preparation and detection system has been developed. In the system the effluent is continuously collected on this moving Ta sheet and evaporated. The dried sample is going into the -particle detection chamber where an array of 12 PIN-detectors is installed. The sample preparation is accomplished within 20 s. Further, from the measurement of radioactivities in each detector, we can measure an elution curve of a nuclide for each condition. The performance of the AIDA-II will be discussed in the conference.
Re solutions by a multi column system for cancer therapeutic experimentsHashimoto, Kazuyuki; Motoishi, Shoji*; Saeki, Hideya*; Sorita, Takami; Matsuoka, Hiromitsu
no journal, ,
Rhenium-188 is a useful generator-produced radioisotope for therapeutic applications because of their energetic beta particles and 
rays suitable for imaging. Because the W parent is obtained in a relatively low specific activity from the irradiation of enriched 
W in a reactor, relatively large volumes of normal saline are required to elute the Re from alumina based W/Re generators. In this study, a simple apparatus for effective concentrations of 188Re solutions from alumina-based W/Re generators was developed by a tandem cation-anion column system. Concentration ratios greater than 50:1 can be achieved with this apparatus.
Toh, Yosuke; Oshima, Masumi; Koizumi, Mitsuo; Furutaka, Kazuyoshi; Kimura, Atsushi; Murakami, Yukihiro*
no journal, ,
no abstracts in English
Ikeda, Atsushi; Yaita, Tsuyoshi; Okamoto, Yoshihiro; Shiwaku, Hideaki; Tsushima, Satoru*; Hennig, C.*
no journal, ,
Neptunium (93Np) is one of the most problematic nuclides in the nuclear fuel reprocessing process and the following radioactive waste disposal. Proper understanding of the Np behavior in the reprocessing process or in the migration process on the geological disposal of radioactive wastes requires vast fundamental information about the chemical properties of Np in solutions. In the present study, Np solution samples with different oxidation states are electrochemically prepared in various aqueous solutions, and the complex structure of Np species in the sample solutions are determined by EXAFS spectroscopy, partly with the help of DFT calculations.
Arisaka, Makoto; Watanabe, Masayuki; Kimura, Takaumi
no journal, ,
Separation of actinide(III) with long-term alpha-radiotoxicity from high level radioactive waste containing lanthanide(III) is indispensable to attain transmutation of actinide(III). Extraction chromatography is one of the promising separation techniques for recovering small amounts of target components from a solution. In this study, to attain the separation of actinides(III) from lanthanides(III) by extraction chromatography, N,N'-dialkyl-N,N'-diphenylpyridine-2,6-dicarboxyamides (PDA) was synthesized as the extractants. This extractant system is prospective to selectively recognize actinides(III) over lanthanides(III) since this has nitrogen donor (pyridyl group). The distribution coefficient, Kd, of both Am(III) and Eu(III) increased with an increase of HNO
concentration. The separation factor (= Kd(Am)/Kd(Eu)) at 3 M HNO was determined to be 6.9. From the result of column experiment, it was found that a complete separation between Am(III) and Eu(III) was archived.
Kasamatsu, Yoshitaka; Toyoshima, Atsushi; Tsukada, Kazuaki; Asai, Masato; Ishii, Yasuo; Nishinaka, Ichiro; Sato, Tetsuya; Li, Z.; Kikuchi, Takahiro; Nagame, Yuichiro; et al.
no journal, ,
Radioactive nuclides of Nb and Ta were produced in the Zr/Hf(p,xn)Nb/Ta and Ge/Gd(F,xn)Nb/Ta reactions at the JAEA tandem accelerator. The products were rapidly transported by He/KCl and He/KF gas-jet systems to the chemistry laboratory. It was found that the transport efficiency using the He/KF gas-jet system is comparable with that by the He/KCl gas-jet system which has been generally used. Subsequently, on-line anion-exchange experiments with the products were performed in HF/HNO solutions. A small physical adsorption of Nb on the surfaces of the tools was observed when the KCl aerosols were used, while better reproducibility of the elution of Nb was obtained using the KF aerosols. We interpret that stable fluoro complexes of Nb are rapidly formed by using the KF aerosols and we can suggest that the He/KF gas-jet system should be used in the on-line anion-exchange experiment of the group 5 elements for the study of the fluoride complexation of the elements.
Toyoshima, Atsushi; Kasamatsu, Yoshitaka; Tsukada, Kazuaki; Kitatsuji, Yoshihiro; Ishii, Yasuo; Tome, Hayato*; Asai, Masato; Nagame, Yuichiro; Haba, Hiromitsu*; Akiyama, Kazuhiko*; et al.
no journal, ,
no abstracts in English
Kitatsuji, Yoshihiro; Okugaki, Tomohiko*; Kasuno, Megumi*; Maeda, Koji*; Kimura, Takaumi; Yoshida, Zenko; Kihara, Sorin*
no journal, ,
no abstracts in English
- coincidenceHatsukawa, Yuichi; Osawa, Takahito; Matsue, Hideaki; Segawa, Mariko; Oshima, Masumi; Toh, Yosuke; Kimura, Atsushi; Koizumi, Mitsuo; Furutaka, Kazuyoshi
no journal, ,
The multiple -ray detection method developed for nuclide quantification has achieved better resolution and sensitivity than the ordinary singles -ray detection method. The INAA combined with this method is called NAAMG (Neutron Activation Analysis with Multiple ray detection) and has been successfully applied to various fields. In the case of neutron activation analysis, measurements of -rays from trace elements are strongly interfered by the -rays from isotopes produced from major elements, e.g., Na-24, Mn-56. Therefore chemical separation processes are sometimes required to eliminate the major elements for determination of the trace elements. Measurements of iridium in geological sample were carried out by this method. Samples were irradiated at the JRR-3. Iridium concentrations in several standard rock samples and geological samples were also measured by this method. Fifty to one hundred mg of each sample were sealed in quartz tube and irradiated together with iridium standard. After irradiation, the - coincidence of multiple rays from the Ir-192 was measured with the Ge detectors array, GEMINI-II. rays from about 10 ppt of iridium in geological samples can be detected by this method.
Kasugai, Yoshimi; Kai, Tetsuya; Otsu, Kiichi; Futakawa, Masatoshi; Ikeda, Yujiro
no journal, ,
Various kinds of the spallation products are generated in the mercury used as the spallation neutron source (JSNS) at the Materials and Life Science Facility in J-PARC. In particular, gas products are accumulated in the gas phase of the mercury tank in the mercury circulation system. An off-gas processing system has been installed in order to process the off-gas and enable the gas release to the environment under the concentration limit of radioactivity. In this presentation, we report the calculation of the amount of the radioactive gas product in the mercury, which is used for the system design as a basis, outline of the off-gas process and the activity measurement of the off-gas after the commissioning of JSNS with low power operation.
Yaita, Tsuyoshi; Ikeda, Takashi; Shuk, D. K.*
no journal, ,
no abstracts in English
-ray analysisMatsue, Hideaki; Ojima, Hitoshi*; Yoshida, Hirokazu*; Asano, Nobuko*; Hasegawa, Shoichi*; Cho, Akio*; Hatsukawa, Yuichi; Segawa, Mariko; Osawa, Takahito; Numao, Tatsuya*; et al.
no journal, ,
no abstracts in English
Li, Z.; Toyoshima, Atsushi; Kasamatsu, Yoshitaka; Asai, Masato; Tsukada, Kazuaki; Nagame, Yuichiro; Haba, Hiromitsu*
no journal, ,
-ray apparatusOshima, Masumi; Toh, Yosuke; Furutaka, Kazuyoshi; Murakami, Yukihiro*; Kimura, Atsushi; Koizumi, Mitsuo
no journal, ,
To achieve the new trace element analysis method of Multiple Prompt -ray Analysis (MPGA) we have completed the construction of the MPGA apparatus, STELLA, at C2-3-2 beam line at the neutron guide hall in JAEA Research Reactor, JRR-3. The MPGA system made of twelve Ge detectors has been completed. A fast data acquisition system for this system has been developed. An automatic liquid nitrogen supply system for Ge detectors and an automatic sample changer enable the automatic measurement. Furthermore, rapid -ray energy calibration and on-line quantification software is developed as well as necessary -ray database for them. In July 2008, we have started the application of STELLA to MPGA based on the Interorganization Atomic Energy Research program by University of Tokyo, Toray Research Center and JAEA. In the talk we present the performance and status of STELLA as well as those of the apparatus at the new facility of J-PARC MLF.
Xe-fullereneWatanabe, Satoshi; Ishioka, Noriko
no journal, ,
no abstracts in English
Cu for medical applicationsWatanabe, Shigeki; Liang, J. X.; Iida, Yasuhiko*; Hanaoka, Hirofumi*; Watanabe, Satoshi; Endo, Keigo*; Ishioka, Noriko
no journal, ,
no abstracts in English