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Shimada, Asako
Bunseki Kagaku, 71(12), p.625 - 633, 2022/12
Cesium-135 is one of the important nuclides to assess the safe disposal of High Level Waste (HLW). Therefore, the calculation code and library to evaluate the Cs concentration in HLW have been improved through comparisons with experimental results. On the other hand, even basic data of
Cs, such as its half-life, have large uncertainty. Because the
Cs/
Cs isotopic ratio suggests its origin and introduction date, the ratios in environmental samples are measured to study global fallout from nuclear weapons testing and nuclear accidents. Such measurement methods was attracted attention, in particular, after the accident at the Fukushima Daiichi Nuclear Power Station. Measurement of the
Cs/
Cs isotopic ratio in environmental samples was challenging because the radiocesium has a very low concentration and it co-exists with huge amounts of Ba isotopes, which are isobaric interfering nuclides, are co-exist. Chemical separation methods were developed to eliminate interfering nuclides and improve the performance of the mass spectrometer to enable the measurement of the ratios. In this review, the features of the
Cs/
Cs isotopic ratio for each origin and recent developments in measurement techniques are summarized.
Haraga, Tomoko; Saito, Shingo*
Bunseki Kagaku, 70(12), p.671 - 679, 2021/12
We developed highly sensitive capillary electrophoresis-laser-induced fluorescence detection methods for lanthanide (Ln) and actinide (An) ions with small sample volume and low emission of waste, by which the radiation risk can be minimized. Specifically, determination of Nd ion in spent nuclear fuel, effective separation between Am and Cm ion, and specific detection of UO in real radioactive samples were achieved by molecular design of fluorescence probes composed of an aminocarboxylate chelating moiety, a fluorophore and a spacer, and unique separation mode based on dynamic ternary complexation. We found that there are appropriate combination of probe and ternary complexation for detection and separation of each Ln and An ions. For example, acyclic and macrocyclic hexadentate is suitable for Ln
, Am
and Cm
, and planer tetradentate with
electron system is specific for UO
, with ppt-sub ppt level detection.
Shimada, Asako
Nihon Bunseki Kagakukai Kanto Shibu Nyusu, (31), p.7 - 8, 2021/00
I am very glad to win a prize, new century award of Kanto branch of The Japan Society for Analytical Chemistry. I deeply appreciate recommender and co-workers. The title of award was "Development of analytical method of difficult to measure nuclides in radioactive wastes", and especially development of analytical method for Am-242m, Mo-93, and I-129 was recognized. By measuring beta-ray of Am-242, which is progeny nuclide of Am-242m and having high intensity and shorter half-life, measuring time was shortened to approximately 1/20 compare to traditional method. Analyzed Mo-93 example was extremely few. When Mo-93 was analyzed via X-ray, Zr-93 and Nb-93m were the interfering nuclides, therefore, separation method of Mo from Zr and Nb was developed and the method was applied to the rubble sample collected at the Fukushima Daiichi Nuclear Power Station (FDNPS). Official method to measure I-129 in environmental samples were optimized to measure I-129 in the contaminated water collected at FDNPS.
Horita, Takuma; Asai, Shiho*; Konda, Miki; Matsueda, Makoto; Hanzawa, Yukiko; Kitatsuji, Yoshihiro
Bunseki Kagaku, 69(10/11), p.619 - 626, 2020/10
Times Cited Count:0 Percentile:0(Chemistry, Analytical)We have developed a Sr adsorption fiber for rapid analysis of Sr. The prepared Sr adsorption fiber has a Sr-extraction layer that densely retains a Sr-selective extractant, an 18-crown-6 ether derivative, on the fiber surface. Hydrophobic group-containing polymer chains embedded onto the surface of the fiber allow to form a hydrophobic phase, incorporating Sr-selective extractants. This unique surface structure provides high adsorption capacity, leading to rapid and highly efficient adsorption of Sr
. The adsorption capacity of the Sr adsorption fiber was 3 times higher than commercially available 18-crown-6 ether derivative-impregnated resin (Sr Resin). The equilibrium adsorption capacity of the Sr adsorption fiber was comparable to the Sr Resin. The retained
Sr was finally determined by a GM counter. The total analysis time including the Sr adsorption and measurement was about 1 hour.
Taguchi, Shigeo; Miyauchi, Hironari*; Horigome, Kazushi; Yamamoto, Masahiko; Kuno, Takehiko
Bunseki Kagaku, 67(11), p.681 - 686, 2018/11
In thermal ionization mass spectrometry, de-gassing is one of the important treatments to release impurities of filaments and to minimize the influence of background. In this work, the effect of the surface change in the tungsten filament induced by the conductively heating treatment on uranium isotopic (U/
U) measurement has been investigated. It was found that the conductively heating treatment of the filament has the effect of smoothing the surface of the filament and also has the effect of improving the deposition of the sample on the filament surface. As a result of either these effects, the precision of uranium isotopic (
U/
U) measurement was improved.
Saito, Kyoichi*; Asai, Shiho
Bunseki Kagaku, 66(11), p.771 - 782, 2017/11
Times Cited Count:1 Percentile:3.7(Chemistry, Analytical)Recovery and purification of rare metals, which are essential ingredients for highly functional materials, generally comes with operational difficulty. In this study, we have developed polymer adsorbents specially designed for highly-efficient adsorption of rare metal ions and exhibited their practical adsorption performances. Radiation-induced graft polymerization, one of the effective modification techniques for polymers, was employed for preparing the proposed adsorbents. Among such adsorbents, a 6-nylon fiber with nucleic-acid base, adenine, on the surface of the fiber demonstrated specific adsorption of ruthenium and palladium ions. In addition, a 6-nylon fiber with an extractant HDEHP (bis (2-ethylhexyl) phophoric acid) that has high affinity for lanthanides, achieved higher separation speed than a commercially available HDEHP-impregnated resin.
Naganawa, Hirochika
Bunseki Kagaku, 66(11), p.797 - 808, 2017/11
Times Cited Count:6 Percentile:24.37(Chemistry, Analytical)A new liquid-liquid extraction method, called the emulsion-flow method, has recently been developed at Japan Atomic Energy Agency (JAEA). The emulsion-flow method, where low cost, simplicity, high efficiency, compactness, safety, and eco-friendly go together, has attracted attention, and has been expected to bring innovation to liquid-liquid extraction technologies. Compared with conventional industrial apparatuses, an emulsion-flow apparatus successfully combines the lowest cost superior to a spray column and the highest performance (the highest efficiency and the highest processing speed) comparable to a centrifugal extractor. Furthermore, the emulsion-flow method can also be used for collecting particulate components by utilizing their aggregation onto a liquid-liquid interface and for purifying water polluted by oil with its remarkable phase-separating ability.
Yomogida, Takumi; Asai, Shiho; Saeki, Morihisa*; Hanzawa, Yukiko; Horita, Takuma; Esaka, Fumitaka; Oba, Hironori*; Kitatsuji, Yoshihiro
Bunseki Kagaku, 66(9), p.647 - 652, 2017/09
Times Cited Count:2 Percentile:7.41(Chemistry, Analytical)Palladium-107 is a long-lived fission product, which can be found in high-level radioactive liquid wastes (HLLW). Determination of the Pd contents in HLLW is essential to evaluate the long-term safety of HLLW repositories. However, the
Pd content in HLLW has not been reported because of difficulties in pretreatment for the measurement. In this study, we investigated applicability of laser-induced photoreduction to HLLW solution: it enables a simple and non-contact separation of Pd. The results showed the recovery of 60% was achieved at the conditions: 40% ethanol, 20 min irradiation, 100 mJ of pulse energy. Additionally, major radionuclides and potentially interfering components in ICP-MS were removed from the simulated HLLW over a wide concentration range of Pd from 0.24 to 24 mg L
, showing the applicability of the proposed separation technique to HLLW samples.
Okamura, Hiroyuki
Bunseki Kagaku, 66(7), p.531 - 532, 2017/07
This paper summarizes the author's doctoral thesis on analytical chemistry. In this study, the ionic liquid (IL) extraction of various metal(II, III) complexes with macrocyclic and anionic chelating ligands has been investigated to clarify the solvent effect of ILs and to demonstrate the specificity and superiority of the IL extraction systems over conventional ones. The evaluation of the extraction equilibrium of Eu(III) with 2-thenoyltrifluoroacetone (Htta) in 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([Cmim][Tf
N]) and time-resolved laser-induced fluorescence spectroscopy revealed the specific solute-solvent interactions between Eu(tta)
and [C
mim][Tf
N]. The IL synergistic extraction with Htta and
-dicyclohexano-18-crown-6 was developed. The extractability of lighter lanthanides(III) was remarkably enhanced by a synergistic effect of crown ethers. A macrocyclic ligand (H
DA18C6) composed of diaza-18-crown-6 and two 4-acyl-5-pyrazolones was synthesized for the extraction of Sr(II). The extraction performance of H
DA18C6 was significantly enhanced only in [C
mim][Tf
N] by the intramolecular cooperative effect.
Saito, Kyoichi*; Kojima, Takashi*; Asai, Shiho
Bunseki Kagaku, 66(4), p.233 - 242, 2017/04
Times Cited Count:1 Percentile:3.7(Chemistry, Analytical)Insoluble cobalt ferrocyanide and sodium titanate specifically capture cesium and strontium ions, respectively, in water contaminated with radionuclides which is found in Fukushima Daiichi NPP. The inorganic compounds used in this study were formed as precipitates in the polymer chain grafted onto a commercially available 6-nylon fiber using radiation-induced graft polymerization. An impregnation structure with the precipitates entangled by the grafted polymer chain through an electrostatic interaction via multipoints was indicated. The resultant insoluble cobalt ferrocyanide- or sodium titanate-impregnated fiber exhibited a higher adsorption rate and adsorption capacity per gram of the inorganic compound for cesium or strontium ions in seawater than conventional granular adsorbents.
Takagai, Yoshitaka*; Furukawa, Makoto*; Kameo, Yutaka; Matsueda, Makoto; Suzuki, Katsuhiko*
Bunseki Kagaku, 66(4), p.223 - 231, 2017/04
Times Cited Count:5 Percentile:20.33(Chemistry, Analytical)no abstracts in English
Ono, Takahiro*; Iizawa, Yushin*; Abe, Yoshinari*; Nakai, Izumi*; Terada, Yasuko*; Satou, Yukihiko; Sueki, Keisuke*; Adachi, Koji*; Igarashi, Yasuhito*
Bunseki Kagaku, 66(4), p.251 - 261, 2017/04
Times Cited Count:32 Percentile:80.23(Chemistry, Analytical)no abstracts in English
Sanada, Yukihisa; Ishizaki, Azusa; Nishizawa, Yukiyasu; Urabe, Yoshimi*
Bunseki Kagaku, 66(3), p.149 - 162, 2017/03
Times Cited Count:9 Percentile:36.42(Chemistry, Analytical)The Great East Japan Earthquake that occurred on 11 March 2011 generated a series of large tsunami waves that caused serious damage to the Fukushima Dai-ichi Nuclear Power Station, following which a large amount of radioactive material was discharged from the nuclear power plant into the environment. The airborne radiation measurement using a manned helicopter was applied to measure the radiation distribution immediately after accident of the Fukushima Dai-ichi Nuclear Power Station as technique to quickly measure the radiation distribution in the wide area. In Japan, this technique was researched and developed in the 1980s. However, this technique and system were not applied immediately after the accident because standardization of analysis was not established and the Japanese system became deteriorated. This technique is important for post-accident of nuclear facility. We summarized the methods of the airborne radiation measurement using a manned helicopter. In addition, measurement results of dose rate distribution at the Fukushima Dai-ichi Nuclear Power Station was shown in this paper.
Horita, Takuma; Asai, Shiho; Konda, Miki; Hanzawa, Yukiko; Saito, Kyoichi*; Fujiwara, Kunio*; Sugo, Takanobu*; Kitatsuji, Yoshihiro
Bunseki Kagaku, 66(3), p.189 - 193, 2017/03
Times Cited Count:1 Percentile:3.7(Chemistry, Analytical)A Sr-selective adsorption fiber was prepared for rapid analysis of Sr content by using radiation-induced emulsion graft polymerization and subsequent chemical modification. A polyethylene fiber with a diameter of 13
m was first immersed in a methanol solution of an epoxy-group-containing vinyl monomer, glycidyl methacrylate (GMA), and polyoxyethylene sorbitol ester (Tween20) as a surfactant for graft-polymerization of GMA. Octadecylamine was then bound to a polymer chain extending from the fiber surface providing hydrophobicity to the polymer chain. Dicyclohexano-18-crown-6 (DCH18C6) was finally impregnated onto the polymer chain via a hydrophobic interaction between the octadecyl moiety of the polymer chain and the cyclohexyl moiety of DCH18C6. The fiber surface structure, characterized by DCH18C6 molecules loosely entangled with polymer chains, afforded realizes the rapid and selective adsorption of Sr ions with an adsorption rate approximately 100 times higher than that of a commercially available Sr-selective resin (Sr Resin).
Haraga, Tomoko
Bunseki Kagaku, 66(2), p.123 - 124, 2017/02
no abstracts in English
Yonezawa, Chushiro*; Shirono, Katsuhiro*; Haraga, Tomoko
Bunseki Kagaku, 66(1), p.27 - 37, 2017/01
Times Cited Count:0 Percentile:0(Chemistry, Analytical)no abstracts in English
Hirao, Norie; Shimoyama, Iwao; Baba, Yuji; Izumi, Toshinori; Okamoto, Yoshihiro; Yaita, Tsuyoshi; Suzuki, Shinichi
Bunseki Kagaku, 65(5), p.259 - 266, 2016/05
Times Cited Count:4 Percentile:15.25(Chemistry, Analytical)After the Fukushima nuclear plant accident, radiocesium was strongly fixed to clay minerals in the soil. Some dry methods with heating are being developed to remove radiocesium from the soil. In this work, we propose a new dry method that combines heat treatment in vacuum and molten salts to reduce the processing temperature in dry methods. Vermiculite saturated with non-radioactive Cs was heated in vacuum, and Cs contents in the vermiculite were compared before and after heating using X-ray photoelectron spectroscopy. Approximately 40% of cesium were removed by heating at 800C for three minutes when only vermiculite was heated. Approximately 70% of cesium were removed by heating at 450
C for three minutes when vermiculite was heated with NaCl/CaCl
mixed salts. Based on these results, this method is expected to reduce temperature and increase efficiency on dry methods for cesium removal from clay minerals.
Esaka, Fumitaka
Ekisupato Oyo Kagaku Sirizu; Kiki Bunseki, p.119 - 135, 2015/09
Bulk analysis has been conventionally used for measuring solid materials. In contrast, surface analysis is extensively used for analyzing chemical compositions and chemical states of solid surface. The surface compositions often differ from those of bulk materials. Recently, doping of impurity elements and deposition of thin films on the surface of the materials are key techniques to fabricate functional materials. Therefore, surface analysis becomes important to characterize such materials. In this paper, the principle and feature of some surface analytical techniques are described.
Kushita, Kohei; Atarashi-Andoh, Mariko; Amano, Hikaru*
Bunseki Kagaku, 63(11), p.867 - 871, 2014/11
Times Cited Count:0 Percentile:0(Chemistry, Analytical)We report here the study of activated gold for the estimation of neutron dose in the environment in the case of JCO criticality accident happened in Tokai, Japan, in 1999. We collected and analyzed 16 gold samples, such as ring, coin or necklace stored at residents houses in the range from 168 to 568 m from the accident place of JCO. They gave activities from 91.9 to 0.322 Bq/g-Au as standardized values at 06:15, Oct. 1, 1999, when the criticality reaction had ceased after 20 hours of continuation. The induced radioactivity of gold samples showed a good correlation as a power function of distance. The induced radioactivity of gold is discussed with reference data to estimate dose equivalent in the environment around JCO. This paper gives an example showing the usefulness of gold in the field of nuclear and radiation studies and applications.
Ozu, Akira; Esaka, Fumitaka; Yasuda, Kenichiro
Bunseki Kagaku, 63(7), p.609 - 617, 2014/07
Times Cited Count:0 Percentile:0(Chemistry, Analytical)Decay ratios of the laser-induced fluorescence emitted from five types of asbestos and six types of building materials in the broad wavelength region from 350 to 700 nm were investigated by using an ultraviolet laser pulse of 266 nm. Dependence of the decay ratios on the wavelength were compared, and evaluated in an attempt to numerically discriminate asbestos from the other building materials. It was observed that the decay ratios of each material were not constant over the wavelength region and varied in the wavelength over time. The fluorescence of asbestos and the building materials except for rock fiber at above 500 nm decayed faster than that at below 500 nm. The wavelength region from 405 to 420 nm was found optimum to identify types of asbestos and to discriminate asbestos from the building materials by comparing the decay ratio at the delay time of 10 ns after the incidence of laser pulse.