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Pu/
Pu isotope ratio analysis of uranium-plutonium mixed particles by alpha- and mass- spectrometryEsaka, Fumitaka; Yasuda, Kenichiro; Suzuki, Daisuke; Magara, Masaaki
no journal, ,
Isotope ratio analysis of individual particles containing nuclear materials in environmental samples taken at nuclear facilities is important to clarify the origin and impact on the environment. Recently, nuclear fuels containing uranium and plutonium are utilized for nuclear reactors. Therefore, the analysis of uranium-plutonium mixed particles is also important. In this study, an analytical technique was developed to measure Pu/Pu isotope ratios by a combination of alpha spectrometry and inductively coupled plasma mass spectrometry.
Yomogida, Takumi; Esaka, Fumitaka; Magara, Masaaki
no journal, ,
Analysis of individual uranium particles in environmental samples from nuclear facilities is useful for detecting nuclear activity. Uranium isotope ratios in the samples are measured to detect nuclear activities related to production of nuclear weapons. We can detect the nuclear activities such as refining, conversion and enrichment process by determination of the chemical form of uranium particles. In this study, we developed a secondary ion mass spectrometry combined with micro-Raman spectroscopy for isotopic and chemical analysis of individual uranium particles. The developed methods have been applied to the analysis of reference uranium materials. As a result, the isotope ratios and the chemical form of individual uranium particle can be analyzed with the proposed method.
Horita, Takuma; Asai, Shiho; Hanzawa, Yukiko; Saito, Kyoichi*; Fujiwara, Kunio*; Sugo, Takanobu*; Kitatsuji, Yoshihiro
no journal, ,
There has been an increasing demand for rapid analysis of 
Sr to ensure a prompt action against the contaminated water in the Fukushima Daiichi NPP. Precedent works demonstrated that Cs adsorption fibers prepared by utilizing graft polymerization technology achieved high-speed removal of 
Cs in the contaminated water. In this study, we have investigated the applicability of such proven technology to the preparation of a Sr adsorption fiber specialized for the selective extraction of Sr. In the prepared fiber, an extractant for Sr
,dicyclohexano-18-crown-6-ether (DCH18C6) was impregnated via hydrophobic interaction between DCH18C6 and the hydrophobic polymer chains attached onto the surface of the fiber. To increase the adsorption capacity, emulsion graft polymerization which promotes the polymer chains to grow longer was applied. The densely-packed DCH18C6 inside the interfacial phase formed by the polymer chains facilitates the efficient adsorption. The amounts of Sr adsorbed is comparable to those of conventional adsorbents, indicating that the prepared fiber has a feasible performance for Sr adsorption.
-diketones on the extracted speciesOkamura, Hiroyuki; Hatakeyama, Mizuki*; Nagatani, Hirohisa*; Nishiyama, Yoshio*; Shimojo, Kojiro; Naganawa, Hirochika; Imura, Hisanori*
no journal, ,
In the separation of lanthanoids (Lns), the synergistic extraction systems have been widely investigated to enhance the extractability and separability. Recently, a method of extraction equilibrium analysis for Ln(III) in the ionic liquid (IL) synergistic extraction system with 2-thenoyltrifluoroacetone (Htta)-trioctylphosphine oxide (TOPO) in 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide was reported. In this study, the extraction equilibrium of Ln in the benzoylacetone (Hba)-TOPO system exhibiting higher Ln separability than the Htta-TOPO system was investigated. The effect of -diketones on the extracted species and the relationship between the extracted species and Ln separability were clarified. A three-dimensional non-linear analysis of log 
-log [ba
]
-log [TOPO]
was applied in the Hba-TOPO synergistic extraction system, and both Ln(ba)
(TOPO)
and Ln(ba)(TOPO)
were found as the extracted species. The formation of 1:1:4 dicationic complex was not observed in the Htta-TOPO synergistic extraction system, indicating that the extracted species is dependent on the acidity of -diketone. Consequently, it was suggested that the formation of the highly hydrophobic 1:1:4 complex is a factor of higher Ln separability.
Asai, Shiho; Saito, Kyoichi*
no journal, ,
ICP-MS is a promising technique for the determination of radionuclides along with various radiometric instruments. However, the tedious chemical separation procedure is generally required to achieve an interference-free measurement. Particularly in the case of highly radioactive samples, a simplified separation procedure is a prerequisite for safe and efficient analyses. In this study, we have developed micro-volume solid phase extraction cartridges that enable high-throughput separation. A disk-shaped porous polymer with the volume of 0.08 cm
is packed inside the cartridge. This porous polymer has functional-group-containing polymer chains, which are densely attached onto the pore surface of the polymer. A wide variety of functional-groups can be bound to the polymer chains, expanding the applicability of our products. This presentation mainly describes the applicability of the proposed cartridges to the separations for ICP-MS measurement of various radionuclides.
Sugita, Tsuyoshi; Shimojo, Kojiro; Okamura, Hiroyuki; Naganawa, Hirochika
no journal, ,
Since the solvent extraction efficiency depends on the ability of extractants, the development of high performance extractants has been strongly desired. In this study, a novel organophosphorus extractant having a tridentate structure was originally synthesized, and its extraction performance was exhaustively evaluated by investigating the extraction of 56 metal ions. As a result, the extraction performance of this extractant was extremely higher than that of conventional organophosphorus extractants for almost all of the metal ions.
Shimojo, Kojiro; Sugita, Tsuyoshi; Yabe, Makoto*; Okamura, Hiroyuki; Ohashi, Akira*; Naganawa, Hirochika
no journal, ,
Solvent extraction is an effective method for the separation and purification of metal ions. The extractant plays a key role in the extraction efficiency and the separation operation. In this study, we have synthesized a novel acidic diamide-type extractant and have comprehensively investigated the extraction of 56 metal ions. It was found that the novel extractant provides excellent extraction performance and separation ability for various rare metal ions such as Sc(III), In(III), Ga(III), and Ni(II) compared with conventional extractants.