Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Oguri, Kaori; Hagura, Naoto*; Yamaguchi, Akiko; Okumura, Masahiko; Matsuura, Haruaki*; Tsunashima, Yasumichi; Aoki, Katsumi; Arai, Yoichi; Watanabe, So
Nuclear Instruments and Methods in Physics Research B, 556, p.165516_1 - 165516_8, 2024/11
Times Cited Count:0 Percentile:0.00(Instruments & Instrumentation)Ningyo-toge is the uranium mine that has been operated in Japan. Various radioactive elements such as Uranium (U), and Radium (Ra) are still present in the mine ground water with very small amount, and behavior of those elements is not fully understood. In this study, we investigated the composition of metal oxides and clay minerals in a soil of slag deposit at the mine, and systematics of adsorption structure of various ions were examined. Identifying the composition and chemical forms of minerals present in the soil of slag can provide useful information for the safety assessment and evaluation of influence on the surrounding environment.
Minowa, Kazuki*; Watanabe, So; Nakase, Masahiko*; Takahatake, Yoko; Miyazaki, Yasunori; Ban, Yasutoshi; Matsuura, Haruaki*
Nuclear Instruments and Methods in Physics Research B, 556, p.165496_1 - 165496_6, 2024/11
Times Cited Count:0 Percentile:0.00(Instruments & Instrumentation)In this study, X-ray absorption near edge structure (XANES) spectral analysis and column experiments were used to verify the selectivity of rare earth (RE) ions by alkyl diamide amine (ADAAM) adsorbent. In addition, the interactions between the N atoms of ADAAM and RE ions were evaluated to determine whether any of the RE ions are a valid simulant for developing a mutual separation process for minor actinides (MAs) in highly radioactive liquid waste. It was confirmed that La and Ce interacted with the amine N atom of ADAAM and they showed a peak shift of the N-K edge XANES spectrum; this finding suggested that a soft interaction is an essential factor influencing ion selectivity. Therefore, the selection factor of RE ions by ADAAM adsorbent was similar to that of MAs. It was concluded that RE ions are reasonable species to simulate MAs.
Arai, Yoichi; Hasegawa, Kenta; Watanabe, So; Watanabe, Masayuki; Minowa, Kazuki*; Matsuura, Haruaki*; Hagura, Naoto*; Katsuki, Kenta*; Arai, Tsuyoshi*; Konishi, Yasuhiro*
Journal of Radioanalytical and Nuclear Chemistry, 333(7), p.3585 - 3593, 2024/07
Times Cited Count:1 Percentile:25.62(Chemistry, Analytical)Yamamoto, Yuri*; Minowa, Kazuki*; Takahatake, Yoko; Watanabe, So; Nakamura, Masahiro; Matsuura, Haruaki*
Electrochemistry (Internet), 92(4), p.043019_1 - 043019_4, 2024/04
Times Cited Count:0 Percentile:0.00(Electrochemistry)In the pyro-reprocessing of spent nuclear fuel, salt bath is normally used in several times, but at final moment, spent salt containing small amount of chloride nuclear fuel material is generated. In terms of managing nuclear fuel materials, it is desirable that the nuclear fuel materials should be recovered from the spent salt. We are proposing methods for recovering nuclear fuel materials using precipitation by oxide addition and distillation for reducing pressure techniques. In this study, we have focused on the behavior of manganese(II), which is one of the radioactivated products. As a result of experiments and thermodynamic simulation, it was found that manganese(II) is likely to be entrained in nuclear fuel materials. Therefore, it is necessary to add a step to separate manganese(II) from nuclear fuel materials.
Sano, Yuichi; Sakamoto, Atsushi; Miyazaki, Yasunori; Watanabe, So; Morita, Keisuke; Emori, Tatsuya; Ban, Yasutoshi; Arai, Tsuyoshi*; Nakatani, Kiyoharu*; Matsuura, Haruaki*; et al.
Proceedings of International Conference on Nuclear Fuel Cycle; Sustainable Energy Beyond the Pandemic (GLOBAL 2022) (Internet), 4 Pages, 2022/07
We developed a hybrid MA(III) recovery process combining MA(III)+Ln(III) co-recovery flowsheet by solvent extraction with TBP and MA(III)/Ln(III) separation flowsheet by simulated moving bed chromatography using HONTA impregnated adsorbents with large particle size porous silica support.
Watanabe, So; Sano, Yuichi; Okada, Makoto*; Matsuura, Haruaki*; Hagura, Naoto*; Kada, Wataru*
Nuclear Instruments and Methods in Physics Research B, 477, p.60 - 65, 2020/08
Times Cited Count:4 Percentile:37.19(Instruments & Instrumentation)IBIL and EXAFS analyses were applied on strucutral analysis of Eu complex formed in adsorbent developed for extraction chromatography. Those analyses revealed slight structural difference between adsorbent and solvent systems.
Watanabe, So; Senzaki, Tatsuya; Shibata, Atsuhiro; Nomura, Kazunori; Takeuchi, Masayuki; Nakatani, Kiyoharu*; Matsuura, Haruaki*; Horiuchi, Yusuke*; Arai, Tsuyoshi*
Journal of Radioanalytical and Nuclear Chemistry, 322(3), p.1273 - 1277, 2019/12
Times Cited Count:6 Percentile:47.74(Chemistry, Analytical)Watanabe, So; Ogi, Hiromichi*; Arai, Yoichi; Aihara, Haruka; Takahatake, Yoko; Shibata, Atsuhiro; Nomura, Kazunori; Kamiya, Yuichi*; Asanuma, Noriko*; Matsuura, Haruaki*; et al.
Progress in Nuclear Energy, 117, p.103090_1 - 103090_8, 2019/11
Times Cited Count:14 Percentile:77.98(Nuclear Science & Technology)Watanabe, So; Katai, Yuya*; Matsuura, Haruaki*; Kada, Wataru*; Koka, Masashi*; Sato, Takahiro*; Arai, Tsuyoshi*
Nuclear Instruments and Methods in Physics Research B, 450, p.61 - 65, 2019/07
Times Cited Count:4 Percentile:35.47(Instruments & Instrumentation)Sano, Yuichi; Watanabe, So; Matsuura, Haruaki*; Nagoshi, Kohei*; Arai, Tsuyoshi*
Journal of Nuclear Science and Technology, 54(10), p.1058 - 1064, 2017/10
Times Cited Count:5 Percentile:39.65(Nuclear Science & Technology)For effective recovery of radioactive elements by adsorbents using polymer-immobilized silica (SiO-P) supports, the microstructure of SiO
-P particles impregnated with CMPO as extractants and their change with the crosslinking degree of polymer (CDP) were investigated using STXM and EXAFS analyses; further, their relation with adsorption/elution behavior was discussed. The adsorption/elution tests using adsorbents with a different CDP demonstrated that a higher CDP inhibited the elution of adsorbed metal ions from the adsorbent. The results of STXM and EXAFS analyses suggested that adsorption by CMPO proceeds through the entire area in the adsorbent and the local structure around adsorbed metal ions is similar irrespective of the CDP. Conversely, STXM analyses implied the capture of eluents such as H
O by polymers with high CDP, which suppresses the prompt elution of adsorbed metal ions from the adsorbent.
Watanabe, So; Sano, Yuichi; Shiwaku, Hideaki; Yaita, Tsuyoshi; Ono, Shimpei*; Arai, Tsuyoshi*; Matsuura, Haruaki*; Koka, Masashi*; Sato, Takahiro*
Nuclear Instruments and Methods in Physics Research B, 404, p.202 - 206, 2017/08
Times Cited Count:4 Percentile:32.88(Instruments & Instrumentation)Abe, Ryoji*; Nagoshi, Kohei*; Arai, Tsuyoshi*; Watanabe, So; Sano, Yuichi; Matsuura, Haruaki*; Takagi, Hideaki*; Shimizu, Nobutaka*; Koka, Masashi*; Sato, Takahiro*
Nuclear Instruments and Methods in Physics Research B, 404, p.173 - 178, 2017/08
Times Cited Count:7 Percentile:51.69(Instruments & Instrumentation)Nagai, Takayuki; Kobayashi, Hidekazu; Sasage, Kenichi; Ayame, Yasuo; Okamoto, Yoshihiro; Shiwaku, Hideaki; Matsuura, Haruaki*; Uchiyama, Takafumi*; Okada, Yukiko*; Nezu, Atsushi*; et al.
JAEA-Research 2016-015, 52 Pages, 2016/11
The local structure of waste elements in simulated waste glasses including V was estimated by using synchrotron XAFS measurement in this study. The results are as follows. (1) V has a high possibility which exists in the glass phase in the case of frit, and V can regard both samples as stable 4 coordination structure. (2) Zn, Ce, Nd, Zr, and Mo exist in the glass phase, and the difference is admitted by the percentage of Ce(III) and Ce(IV) by the composition. (3) Ru is separated from the glass phase as RuO crystalline, both of metal and oxide exist in Rh, and Pd is separated out as metal. (4) It was confirmed that the regularity of the local structure of Zr and Mo in the molten glasses retreats as a result of the XAFS measurement at high temperature. (5) The XAFS measurement of molten glasses were performed at 1200
C, so it would be possible to acquire excellent data by improving the shapes of the sample cell.
Numakura, Masahiko*; Sato, Nobuaki*; Bessada, C.*; Okamoto, Yoshihiro; Akatsuka, Hiroshi*; Nezu, Atsushi*; Shimohara, Yasuaki*; Tajima, Keisuke*; Kawano, Hirokazu*; Nakahagi, Takeshi*; et al.
Progress in Nuclear Energy, 53(7), p.994 - 998, 2011/11
Times Cited Count:13 Percentile:67.48(Nuclear Science & Technology)X-ray absorption fine structure (XAFS) measurements on thorium fluoride in molten lithium-calcium fluoride mixtures and molecular dynamics (MD) simulation of zirconium and yttrium fluoride in molten lithium-calcium fluoride mixtures have been carried out. In the molten state, coordination number of thorium and inter ionic distances between thorium and fluorine in the first neighbor are nearly constant in all mixtures. However the fluctuation factors (Debye-Waller factor and C cumulant) increase until
CaF
= 0.17 and decrease by addition of excess CaF
. It means that the local structure around Th
is disordered until
CaF
=0.17 and stabilized over
CaF
= 0.17. The variation of fluctuation factors is related to the number density of F
in ThF
mixtures and the stability of local structure around Th
increases with decreasing the number density of F
in ThF
mixtures. This tendency is common to those in the ZrF
and YF
mixtures.
Uehara, Akihiro*; Fujii, Toshiyuki*; Matsuura, Haruaki*; Sato, Nobuaki*; Nagai, Takayuki; Minato, Kazuo; Yamana, Hajimu*; Okamoto, Yoshihiro
Proceedings in Radiochemistry, 1(1), p.161 - 165, 2011/09
Pauvert, O.*; Salanne, M.*; Zanghi, D.*; Simon, C.*; Reguer, S.*; Thiaudire, D.*; Okamoto, Yoshihiro; Matsuura, Haruaki*; Bessada, C.*
Journal of Physical Chemistry B, 115(29), p.9160 - 9167, 2011/07
Times Cited Count:77 Percentile:83.76(Chemistry, Physical)The structure of molten AF-ZrF system (A
=Li
, Na
, K
) is studied using EXAFS spectroscopy with molecular dynamics simulations. From the Zr
solvation shell point of view, we observe a progressive stabilization of the 7-fold and then of the 6-fold coordinated complexes when passing from Li
to Na
and K
as a "counterion". Particular attention is given to the systems consisting of 35 mol% of ZrF
. At that particular composition, the ZrF
complex predominates largely whatever the nature of the alkali. The calculated vibrational properties of this complex are in excellent agreement with a previous Raman spectroscopy experiment on molten KF-ZrF
. The most important differences are observed for the lifetime of these octahedral units. On a larger scale, an intense first sharp diffraction peak is observed for the Zr
-Zr
partial structure factor, which can be attributed to the correlations between the octahedral units formed.
Pauvert, O.*; Zanghi, D.*; Salanne, M.*; Simon, C.*; Rakhamatullin, A.*; Matsuura, Haruaki*; Okamoto, Yoshihiro; Vivet, F.*; Bessada, C.*
Journal of Physical Chemistry B, 114(19), p.6472 - 6479, 2010/05
Times Cited Count:65 Percentile:79.77(Chemistry, Physical)The structure of the molten LiF-ZrF system up to 50 mol% ZrF
was investigated by combining high-temperature nuclear magnetic resonance (NMR) and extended X-ray absorption fine structure (EXAFS) experiments with molecular dynamics (MD) calculations.
Zr high-temperature NMR experiments give an average coordination of 7 for the zirconium ion on all domains of composition. MD simulations, in agreement with EXAFS experiments at the K-edge of Zr, provide evidence for the coexistence of three different Zr-based complexes, [ZrF
]
, [ZrF
]
, and [ZrF
]
, in the melt.
Okamoto, Yoshihiro; Iwadate, Yasuhiko*; Fukushima, Kazuko*; Matsuura, Haruaki*; Minato, Kazuo
Journal of Physics and Chemistry of Solids, 66(2-4), p.452 - 455, 2005/02
Times Cited Count:6 Percentile:29.10(Chemistry, Multidisciplinary)The structure of molten PbCl was investigated by using X-ray diffrtaction(XRD) and X-ray absorption fine structure(XAFS) analysis techniques. From the fourier transformation analysis if the XRD data, the nearest Pb
-Cl
interaction consists of two kinds of interactions; rigid 4-fold tetrahedron and 2-3 loose coordination. The XAFS result shows a local structure is the 4-fold coordination in the melt.
Matsuura, Haruaki*; Nezu, Atsushi*; Arai, Tsuyoshi*; Ono, Shimpei*; Sano, Yuichi; Watanabe, So
no journal, ,
no abstracts in English
Myochin, Munetaka; Kofuji, Hirohide; Yamana, Hajimu*; Shirai, Osamu*; Yamamura, Tsutomu*; Umesaki, Norimasa*; Matsuura, Haruaki*; Kajinami, Akihiko*; Iwadate, Yasuhiko*; Otori, Norikazu*; et al.
no journal, ,
no abstracts in English