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Omer, M.; Shizuma, Toshiyuki*; Hajima, Ryoichi*; Koizumi, Mitsuo
Radiation Physics and Chemistry, 198, p.110241_1 - 110241_7, 2022/09
Times Cited Count：2 Percentile：53.91(Chemistry, Physical)Collaborative Laboratories for Advanced Decommissioning Science; The University of Tokyo*
JAEA-Review 2022-007, 59 Pages, 2022/06
JAEA-Review-2022-007.pdf:2.09MB
The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2020. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2018, this report summarizes the research results of the "Identification of altered phases of fuel debris by laser fluorescence spectroscopy" conducted from FY2018 to FY2021 (this contract was extended to FY2021). Since the final year of this proposal was FY2021, the results for four fiscal years were summarized. The present study aims to identify alteration phases occurring on the surface fuel debris at various conditions, using time-resolved laser fluorescence spectroscopy (TRLFS), which is a selective analytical technique for U(VI), a major constituent of fuel debris and stable in oxidizing conditions.
Collaborative Laboratories for Advanced Decommissioning Science; The University of Tokyo*
JAEA-Review 2020-053, 64 Pages, 2021/01
JAEA-Review-2020-053.pdf:3.58MB
JAEA/CLADS had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project in FY2019. Among the adopted proposals in FY2019, this report summarizes the research results of the "Identification of Altered Phases of Fuel Debris by Laser Fluorescence Spectroscopy" conducted in FY2019.
Collaborative Laboratories for Advanced Decommissioning Science; The University of Tokyo*
JAEA-Review 2019-030, 66 Pages, 2020/03
JAEA-Review-2019-030.pdf:7.11MB
JAEA/CLADS, had been conducting the Center of World Intelligence Project for Nuclear Science/Technology and Human Resource Development (hereafter referred to "the Project") in FY2018. The Project aims to contribute to solving problems in nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. Among the adopted proposals in FY2018, this report summarizes the research results of the "Identification of Altered Phases of Fuel Debris by Laser Fluorescence Spectroscopy". In the present study, we focus on uranium that is the main component element in debris, and identify the altered phase produced on the debris surface under various conditions by time-resolved laser fluorescence spectroscopy (TRLFS) with high sensitivity to hexavalent uranium (U(VI)) that is stable in oxidation environment. In particular, further high-sensitive and high-resolution measurements are implemented by improving the fluorescence yields and suppressing the broadening of the peaks through the measurements at ultra-low temperature. In addition, with the supports by quantum chemical calculations, multivariate analysis, and machine learning, the method will lead to the identification of multicomponent and heterogeneous altered phase of fuel debris.
Al; Its low-lying multiplet structureShizuma, Toshiyuki*; Omer, M.; Hajima, Ryoichi*; Shimizu, Noritaka*; Utsuno, Yutaka
Physical Review C, 100(1), p.014307_1 - 014307_6, 2019/07
Times Cited Count：7 Percentile：59.68(Physics, Nuclear)Koizumi, Mitsuo
Proceedings of 41st ESARDA Annual Meeting (Internet), p.260 - 267, 2019/05
on Na-montmorillonite studied by time-resolved laser fluorescence spectroscopy and surface complexation modelingSasaki, Takayuki*; Ueda, Kenyo*; Saito, Takumi; Aoyagi, Noboru; Kobayashi, Taishi*; Takagi, Ikuji*; Kimura, Takaumi; Tachi, Yukio
Journal of Nuclear Science and Technology, 53(4), p.592 - 601, 2016/04
Times Cited Count：12 Percentile：74.83(Nuclear Science & Technology)The influences of pH and the concentrations of Eu and NaNO
on the sorption of Eu to Na-montmorillonite were investigated through batch sorption measurements and time-resolved laser fluorescence spectroscopy (TRLFS). The pH had a little effect on the distribution coefficients (Kd) in 0.01 M NaNO, whereas the Kd strongly depended on pH at 1 M NaNO. A cation exchange model combined with a one-site non-electrostatic surface complexation model was successfully applied to the measured Kd. The TRLFS spectra of Eu sorbed were processed by parallel factor analysis (PARAFAC), which corresponded to one outer-sphere (factor A) and two inner-sphere (factor B and C) complexes. It turned out that factors A and B correspond to Eu sorbed by ion exchange sites and inner-sphere complexation with hydroxyl groups of the edge faces, respectively. Factor C became dominant at relatively high pH and ionic strength and likely correspond to the precipitation of Eu(OH) on the surface.
Oba, Masaki; Miyabe, Masabumi; Akaoka, Katsuaki; Wakaida, Ikuo
Japanese Journal of Applied Physics, 55(2), p.022401_1 - 022401_4, 2016/02
Times Cited Count：3 Percentile：14.94(Physics, Applied)We used laser-induced fluorescence imaging with a varying beam focal point to observe ablation plumes from metal and oxide samples of gadolinium. The plumes expand vertically when the focal point is far from the sample surface. In contrast, the plume becomes hemispherical when the focal point is on the sample surface. In addition, the internal plume structure and the composition of the ablated atomic and ionic particles also vary significantly. The fluorescence intensity of a plume from a metal sample is greater than that from an oxide sample, which suggests that the number of monatomic species produced in each plume differs. For both the metal and oxide samples, the most intense fluorescence from atomic (ionic) species is observed with the beam focal point at 3-4 mm (2 mm) from the sample surface.
Seya, Michio; Kobayashi, Naoki; Naoi, Yosuke; Hajima, Ryoichi; Soyama, Kazuhiko; Kureta, Masatoshi; Nakamura, Hironobu; Harada, Hideo
Book of Abstracts, Presentations and Papers of Symposium on International Safeguards; Linking Strategy, Implementation and People (Internet), 8 Pages, 2015/03
JAEA-ISCN has been implementing basic development programs of the advanced NDA technologies for nuclear material (NM) since 2011JFY (Japanese Fiscal Year), which are (1) NRF (Nuclear resonance fluorescence) NDA technology using laser Compton scattered (LCS) 
-rays (intense mono-energetic -rays), (2) Alternative to 
He neutron detection technology using ZnS/B
O ceramic scintillator, and (3) NRD (Neutron resonance densitometry) using NRTA (Neutron resonance transmission analysis) and NRCA (Neutron resonance capture analysis). These programs are going to be finished in 2014JFY and have demonstration tests in February - March 2015.
Seya, Michio; Kureta, Masatoshi; Soyama, Kazuhiko; Nakamura, Hironobu; Harada, Hideo; Hajima, Ryoichi
Proceedings of INMM 55th Annual Meeting (Internet), 10 Pages, 2014/07
JAEA has been implementing development programs of basic technologies of the following advanced NDA (non-destructive assay) of nuclear material (NM) for nuclear safeguards and security. (1) Alternative to He neutron detection using ZnS/BO ceramic scintillator, (2) NRD (neutron resonance densitometry) using NRTA (neutron resonance transmission analysis) and NRCA (neutron resonance capture analysis), (3) NRF (nuclear resonance fluorescence)-NDA using laser Compton scattered (LCS) -rays (intense mono-energetic -rays). The development program (1) is for NDA systems that use ZnS/BO ceramic scintillator as alternative neutron detector to He for coming shortage of its supply. The program (2) is for a NDA system of isotopic composition measurement (non-destructive mass spectroscopy) in targets such as particle-like melted fuel debris using NRTA and NRCA. The program (3) is for NDA systems using a specific NRF reaction of certain Pu/U isotope caused by mono-energetic LCS -ray with energy tuned to the specific excited state of the isotope. This paper introduces above three programs.
Takahashi, Yoshio*; Murata, Miho*; Kimura, Takaumi
Journal of Alloys and Compounds, 408-412, p.1246 - 1251, 2006/02
Times Cited Count：24 Percentile：75.32(Chemistry, Physical)no abstracts in English
Murakami, Hiroshi
Chemical Physics Letters, 417(4-6), p.550 - 554, 2006/01
Times Cited Count：5 Percentile：15.98(Chemistry, Physical)no abstracts in English
Imazono, Takashi; Yanagihara, Mihiro*
Photon Factory News, 22(3), p.18 - 22, 2004/11
Using soft-X-ray fluorescence spectroscopy with photon incidence at a critical angle of total reflection, it was made clear that SiO
existed within a depth of a few nanometers from the surface of Fe/Si multilayers. It was generated by oxidation of the interdiffused Fe
Si layer nearest to the topmost Fe layer. Consequently, the FeSi layer was found to decrease in thickness. This result suggests that the total-reflection soft-X-ray fluorescence spectroscopy is fairly useful to analyze the chemical state of elements to a depth of a few nanometers from the surface.
Tian, G.*; Kimura, Takaumi; Yoshida, Zenko; Zhu, Y.*; Rao, L.*
Radiochimica Acta, 92(8), p.495 - 499, 2004/08
Times Cited Count：16 Percentile：70(Chemistry, Inorganic & Nuclear)no abstracts in English
Maekawa, Yasunari; Suzuki, Yasuyuki; Maeyama, Katsuya*; Yonezawa, Noriyuki*; Yoshida, Masaru
Chemistry Letters, 33(2), p.150 - 151, 2004/02
Times Cited Count：4 Percentile：21.74(Chemistry, Multidisciplinary)Since well-characterized chemical modification of pore inner surfaces in polymer membranes should be very important from the view point of synthetic chemistry of polymer surfaces as well as designing materials for application such as separation membranes and nanoscopic electronic devices, we reported herein the chemical modification of internal surfaces of the cylindrical pores with 0.31 and 0.54 
m in diameter through the reaction of the carboxylic acids on the surfaces with the alkylation reagent bearing a pyrene fluorophore. The incorporation of the fluorophore on the pore internal surfaces were successfully confirmed by the fluorescence microscope images of the membrane reacting with the alkylation reagent bearing a pyrene fluorophore.
Domin and 
L., obtained by crossing with pollen exposed to helium ion beams or -raysKitamura, Satoshi; Inoue, Masayoshi*; Omido, Nobuko*; Fukui, Kiichi*; Tanaka, Atsushi
Nuclear Instruments and Methods in Physics Research B, 206, p.548 - 552, 2003/05
Times Cited Count：8 Percentile：50.24(Instruments & Instrumentation)no abstracts in English
Li, J.; Maekawa, Yasunari; Yamaki, Tetsuya; Yoshida, Masaru
Macromolecular Chemistry and Physics, 203(17), p.2470 - 2474, 2002/12
Times Cited Count：13 Percentile：42.68(Polymer Science)Chemical modification of the hydrophilic surface of poly(ethylene terephthalate) (PET) was examined by the selective alkylation of the acid salt on the surface using acylbromides as an electrophile with catalytic potassium fluoride. The hydrophobicity of the PET surface increased as the alkylation reaction of the hydrolyzed surface proceeded. The chemical incorporation of the alkylation reagents was confirmed by the fluorine peaks in X-ray photoelectron spectroscopy (XPS) from the fluorinated reagents. Exponential increases were observed in the emission and excitation intensities of fluorescence spectra during the reaction of the surface with a fluorescent reagent. This indicated the esterification of carboxylic acids on the surface without deterioration of the reactions even at the later stages. The relation between changes in contact angles and the fluorescence spectra revealed that the hydrophobicity of a surface was quickly restored at the beginning of a reaction.
Yoshikawa, Kiyoshi*; Inoue, Nobuyuki*; Yamazaki, Tetsuo*; Makino, Keisuke*; Yamamoto, Yasushi*; Toku, Hisayuki*; Masuda, Kai*; Kii, Toshiteru*; Onishi, Masami*; Horiike, Hiroshi*; et al.
JAERI-Tech 2002-020, 63 Pages, 2002/03
JAERI-Tech-2002-020.pdf:4.94MB
no abstracts in English
Goto, Masahiro*; Kawanishi, Shunichi; Fukumura, H.*
Applied Surface Science, 154-155, p.701 - 705, 2000/02
Times Cited Count：15 Percentile：61.51(Chemistry, Physical)no abstracts in English
Goto, Masahiro*; Ichinose, Yuji; Kawanishi, Shunichi; Fukumura, H.*
Japanese Journal of Applied Physics, Part 2, 38(1A-B), p.L87 - L88, 1999/01
Times Cited Count：8 Percentile：39.82(Physics, Applied)no abstracts in English
