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Tei, C.; Otaka, Masahiko; Kuwahara, Daisuke*
Chemical Physics Letters, 829, p.140755_1 - 140755_6, 2023/10
Times Cited Count：0 Percentile：0.01(Chemistry, Physical)We were able to detect the nuclear magnetic resonance (NMR) signal of a liquid sodium clinging to the interface of solid metal particles for the first time. In this study, we confirmed the difference in the relaxation times due to the difference in the interactions between liquid sodium and metal particles suspended in the liquid sodium. It was found that the surface of the micro titanium particles and liquid metallic sodium interact physically, not chemically.
Saito, Junichi; Monbernier, M.*
Surfaces and Interfaces (Internet), 41, p.103248_1 - 103248_8, 2023/10
Times Cited Count：0 Percentile：0.01(Chemistry, Physical)Collaborative Laboratories for Advanced Decommissioning Science; University of Tsukuba*
JAEA-Review 2020-037, 53 Pages, 2020/12
JAEA-Review-2020-037.pdf:3.46MB
JAEA/CLADS had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project in FY2019. Among the adopted proposals in FY2018, this report summarizes the research results of the "Upgrading of Recovery Method for Radioactive Microparticles by Heavy Liquid Separation Aiming to Volume Reduction of Contaminated Soil" conducted in FY2019.
Collaborative Laboratories for Advanced Decommissioning Science; University of Tsukuba*
JAEA-Review 2019-023, 33 Pages, 2020/01
JAEA-Review-2019-023.pdf:1.97MB
CLADS, JAEA, 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. 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 'Upgrading of Recovery Method for Radioactive Microparticles by Heavy Liquid Separation Aiming to Volume Reduction of Contaminated Soil'. After the accident of the Fukushima Daiichi Nuclear Power Station, radioactive cesium has been heterogeneously distributed in surface soil due to the existence of radioactive microparticles and clay minerals. Therefore, the selective removal of these microparticles will lead to the volume reduction of contaminated soil. The present study examines methods for selectively removing radioactive microparticles from soil. Also, in order to reduce the volume of contaminated soil, we search a possibility to practically apply the separation method that uses the difference in specific gravity of particles (heavy liquid separation method).
Matsushita, Kentaro; Ito, Kei*; Ezure, Toshiki; Tanaka, Masaaki
Dai-24-Kai Doryoku, Enerugi Gijutsu Shimpojiumu Koen Rombunshu (USB Flash Drive), 5 Pages, 2019/06
In the design study on a sodium-cooled fast reactor (SFR), a numerical simulation code named SYRENA has been developed in Japan Atomic Energy Agency to analyze the behavior of gas bubbles and/or dissolved gas in the primary coolant system. In the present study, the effect of the non-condensable gas entrainment at the free surface on the bubble and the dissolved gas behavior in the primary coolant system were investigated for a typical pool type reactor, and also effect of a dipped-plate (D/P) installed below the free surface in the reactor vessel to suppress the gas bubble entrainment into the primary coolant system was especially investigated. It was clarified that the D/P was influential to the non-condensable gas behavior and the molar flow rate of gas bubbles in the primary coolant system varies depending on the relationship between the gas entrainment rate at the free surface and the exchange flow rate through the D/P.
Matsushita, Kentaro; Ito, Kei*; Ezure, Toshiki; Tanaka, Masaaki
Proceedings of 27th International Conference on Nuclear Engineering (ICONE-27) (Internet), 9 Pages, 2019/05
A numerical simulation code named SYRENA has been developed in JAEA to analyze the behavior of entrained bubbles and dissolved gas in the primary coolant of sodium-cooled fast reactor (SFR). In the present study, a flow network model of SYRENA to a hypothetical pool type reactor was developed and the non-condensable gas behavior was investigated through the comparison with that in the loop type reactor. The effect of the dipped-plate (D/P) tentatively introduced into the pool-type reactor on the gas behavior was investigated through the parametric analyses about the sodium exchange flow rate through the D/P and the gas entrainment rate at the free surface. It was suggested that the increase in the exchange flow rate through the D/P doesn't always work to decrease the bubble volume in the primary coolant system.
Sugimoto, Taro*; Saito, Shimpei*; Kaneko, Akiko*; Abe, Yutaka*; Uchibori, Akihiro; Ohshima, Hiroyuki
Proceedings of 26th International Conference on Nuclear Engineering (ICONE-26) (Internet), 7 Pages, 2018/07
A computational fluid dynamics code for a sodium-water reaction phenomenon in a steam generator of sodium-cooled fast reactors has been developed. In order to provide the data for validation of this code, the visualization experiment on liquid droplet entrainment in the high-pressure air jet submerged in the water pool was carried out. The experiment successfully elucidated the behavior, such as atomization of the relatively large diameter liquid droplet generated from the gas-liquid interface.
Itami, Toshio*; Saito, Junichi; Ara, Kuniaki
Metals, 5(3), p.1212 - 1240, 2015/09
Times Cited Count：2 Percentile：4.14(Materials Science, Multidisciplinary)A new kind of suspension liquid was developed by dispersing Ti nanoparticles (10 nm) in liquid Na, which was then determined by TEM (transmission electron microscopy) analysis. The volume fraction was estimated to be 0.0088 from the analyzed Ti concentration (2 at.%) and the densities of Ti and Na. This suspension liquid, Liquid Sodium containing nanoparticles of titanium (LSnanop), shows, despite only a small addition of Ti nanoparticles, many striking features, namely a negative deviation of 3.9% from the ideal solution for the atomic volume, an increase of 17% in surface tension, a decrease of 11% for the reaction heat to water, and the suppression of chemical reactivity to water and oxygen. The decrease in reaction heat to water seems to be derived from the existence of excess cohesive energy of LSnanop. The excess cohesive energy was discussed based on simple theoretical analyses, with particular emphasis on the screening effect. The suppression of reactivity is discussed with the relation to the decrease of heat of reaction to water or the excess cohesive energy, surface tension, the action as a plug of Ti oxide, negative adsorption on the surface of LSnanop, and percolation.
Uchibori, Akihiro; Ohshima, Hiroyuki
Proceedings of 16th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-16) (USB Flash Drive), p.533 - 544, 2015/08
For assessment of the wastage environment under tube failure accident, a mechanistic computer code called SERAPHIM calculating compressible multicomponent multiphase flow with sodium-water chemical reaction has been developed. In this study, applicability of the SERAPHIM code including the numerical model for liquid droplet entrainment and transport was investigated through the analysis of the basic experiment and the experiment under actual condition of the steam generator. In the analysis of the basic experiment, the calculated pressure variation during liquid droplet entrainment was consistent with the experimental result. In the analysis of the actual condition, the calculated temperature distribution agreed with the measurement result well. The region with higher impingement velocity of the liquid droplet was close to the wastage region confirmed in the experiment. It was demonstrated that the SERAPHIM code could predict the wastage environment under the actual condition.
Kamiyama, Kenji; Konishi, Kensuke; Sato, Ikken; Toyooka, Junichi; Matsuba, Kenichi; Suzuki, Toru; Tobita, Yoshiharu; Pakhnits, A. V.*; Vityuk, V. A.*; Vurim, A. D.*; et al.
Proceedings of 10th International Topical Meeting on Nuclear Thermal Hydraulics, Operation and Safety (NUTHOS-10) (USB Flash Drive), 8 Pages, 2014/12
Morimoto, Yoshiki*; Kato, Sayuri*; Toda, Naohiro*; Katayama, Yoshinori; Tsuji, Kazuhiko*; Yaoita, Kenichi*; Shimomura, Osamu
Review of High Pressure Science and Technology, 7, p.245 - 247, 1998/03
X-ray diffraction for liquid Rb and liquid Na has been measured under pressure up to 6 GPa using synchrotron radiation. Volume dependences of static structure factor 
and pair distribution function 
were obtained to the volume range 
of 0.52 for liquid Rb and 
of 0.73 for liquid Na to investigate the effect of the electronic change on the structure of liquid metals. With increasing pressure, the peaks of of both liquid Rb and liquid Na shift towards higher 
, and the heights of the first peak increase. Theses volume dependences of the structural data are compared with those for other metals under pressure and expanded fluids.
Yaoita, Kenichi*; Katayama, Yoshinori; Tsuji, Kazuhiko*; Kikegawa, Takumi*; Shimomura, Osamu
Review of Scientific Instruments, 68(5), p.2106 - 2110, 1997/05
Times Cited Count：34 Percentile：87.27(Instruments & Instrumentation)An optical device called a multichannel collimator (MCC) was developed to rapidly perform an angle-dispersive diffraction using a multi-anvil press (MAP) with synchrotron radiation. The MCC consists of multiple channels of collimators in a radial alignment. This eliminates diffraction from the materials surrounding the sample so that we can obtain high-quality diffraction from samples in a MAP using an imaging plate. We have installed a MCC system on a MAP named MAX90 at the Photon Factory, National Laboratory for High Energy Physics. Performance of the MCC has been satisfactorily evaluated, and diffraction patterns of liquid sodium and liquid gallium under 4.8 GPahave been succesfully obtained using this system.
Chihara, Junzo; *
Molecular Simulation, 12(3-6), p.187 - 195, 1994/00
Times Cited Count：3 Percentile：14.84(Chemistry, Physical)no abstracts in English
BeF
and NaBeF
by X-ray diffraction*; ; *; Furukawa, Kazuo
J.Chem.Soc.,Faraday Trans.,I, 78, p.2051 - 2058, 1982/00
no abstracts in English
Junkatsu, 23(11), p.856 - 857, 1978/11
no abstracts in English
Katsuta, Hiroji; Furukawa, Kazuo
Nuclear Technology, 31(2), p.218 - 231, 1976/02
Times Cited Count：11no abstracts in English
;
JAERI-M 5171, 21 Pages, 1973/02
no abstracts in English
IEEE(Inst.Electr.Electron.Eng.)Trans.Instrum.Meas., NS-19(1), p.899 - 906, 1972/02
no abstracts in English
; ; ; ;
Journal of Nuclear Materials, 40, p.213 - 220, 1971/00
Times Cited Count：7no abstracts in English
S.IWAI*; M.ISHII*; Nozawa, Masao*; Tamura, T.*; Abe, Y.*; A.TERAMOTO*; M.AKIYAMA*
ANL-7520 PART-II, p.121 - 129, 1968/00
no abstracts in English
Furukawa, Kazuo; ;
JAERI 1129, 27 Pages, 1967/03
no abstracts in English
