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Journal Articles

Kinetic analysis of mass transfer of Eu(III) in extractant-impregnated polymer-layered silica particle in multiple-ion distribution system

Miyagawa, Akihisa*; Hayashi, Naoki*; Iwamoto, Hibiki*; Arai, Tsuyoshi*; Nagatomo, Shigenori*; Miyazaki, Yasunori; Hasegawa, Kenta; Sano, Yuichi; Nakatani, Kiyoharu*

Analytical Sciences, 40(2), p.347 - 352, 2024/02

 Times Cited Count:0 Percentile:0.00(Chemistry, Analytical)

The Eu(III) distribution mechanism in single extractant-impregnated polymer-layered silica particle in a complex solution containing multiple lanthanide ions was investigated using fluorescence microspectroscopy. The rate-determining step was the reaction of Eu(III) with the two extractant molecules. The obtained mechanism and rate constants agreed with those of the single-ion distribution system, in which Eu(III) was distributed to the particles in the Eu(III) solution.

Journal Articles

An Analytical model to decompose mass transfer and chemical process contributions to molecular iodine release from aqueous phase under severe accident conditions

Zablackaite, G.; Shiotsu, Hiroyuki; Kido, Kentaro; Sugiyama, Tomoyuki

Nuclear Engineering and Technology, 56(2), p.536 - 545, 2024/02

 Times Cited Count:1 Percentile:75.38(Nuclear Science & Technology)

Journal Articles

Eu(III) transfer in single $$N,N,N',N'$$-tetraoctyldiglycolamide-impregnated polymer-coated silica particle using fluorescence microspectroscopy; Transfer mechanism and effect of polymer crosslinking degree

Miyagawa, Akihisa*; Takahashi, Takumi*; Kuzure, Yoshiaki*; Iwamoto, Hibiki*; Arai, Tsuyoshi*; Nagatomo, Shigenori*; Watanabe, So; Sano, Yuichi; Nakatani, Kiyoharu*

Analytical Sciences, 39(11), p.1929 - 1936, 2023/11

 Times Cited Count:1 Percentile:17.17(Chemistry, Analytical)

In this study, we revealed the Eu(III) distribution in a single diglycolamide-derivative extractant (TODGA)-impregnated polymer-coated silica particle. The reaction of Eu(III) with two TODGA molecules in the polymer layer was the rate-limiting process, as evidenced by the absence of any correlation between the rate constants (k$$_{1}$$ and k$$_{-1}$$) and concentrations of Eu(III) and HNO$$_{3}$$.

Journal Articles

Competitive distribution of europium and samarium based on reaction rate-limiting process in nitrilotriacetamide extractant-impregnated polymer-coated silica particles

Miyagawa, Akihisa*; Hayashi, Naoki*; Iwamoto, Hibiki*; Arai, Tsuyoshi*; Nagatomo, Shigenori*; Miyazaki, Yasunori; Hasegawa, Kenta; Sano, Yuichi; Nakatani, Kiyoharu*

Bulletin of the Chemical Society of Japan, 96(9), p.1019 - 1025, 2023/09

 Times Cited Count:2 Percentile:30.87(Chemistry, Multidisciplinary)

In the present study, we have elucidated the mass transfer mechanism of Eu(III) and Sm(III) in the solution with these ions in single nitrilotriacetamide (NTA) extractant-impregnated polymer-coated silica particle. The rate-limiting process of mass transfer was the reaction process of ions with NTA molecules, in which the NO$$_{3}$$$$^{-}$$ ions were not involved, which was consistent with that obtained in single ion distribution system.

Journal Articles

Development of numerical analysis method of oxygen concentration near wall of lead-bismuth eutectic channel

Watanabe, Nao; Yamashita, Susumu; Uesawa, Shinichiro; Nishihara, Kenji; Yoshida, Hiroyuki

Proceedings of 20th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-20) (Internet), p.3522 - 3534, 2023/08

Accelerator-driven system (ADS), the coolant of which is lead-bismuth eutectic (LBE), has been designed by Japan Atomic Energy Agency. Estimating corrosion rate at the wall surface of LBE channel is an important issue in considering safety and the life of the entire structure. The corrosion rate depends on state of oxygen layers forming at the material surface. Therefore, this study aims to develop a method to evaluate the corrosion rate in ADS for the design study by estimation of the oxide layer growth and dissolution (OLGD) rates by means of numerical analysis. The OLGD rates, mass transfer rates of oxygen and iron between the material and LBE and advection-diffusion rates of them in LBE depend on each other. Therefore, in order to estimate OLGD rates, the three numerical analysis models should be coupled. For the advection-diffusion calculation, to use CFD code should be reasonable approach to analyze complex flow in ADS, while for the OLGD and the mass transfer calculation, to use some correlation equations should be reasonable because their scales are much smaller than the advection-diffusion. The present work has developed the analysis method of OLGD rates by using JUPITER code, which is CFD code developed in JAEA. In terms of the correlation equations of OLGD and mass transfer rates, existing models used in a previous study were used with modified.

Journal Articles

Kinetic mass transfer behavior of Eu(III) in nitrilotriacetamide-impregnated polymer-coated silica particles

Miyagawa, Akihisa*; Hayashi, Naoki*; Kuzure, Yoshiaki*; Takahashi, Takumi*; Iwamoto, Hibiki*; Arai, Tsuyoshi*; Nagatomo, Shigenori*; Miyazaki, Yasunori; Hasegawa, Kenta; Sano, Yuichi; et al.

Bulletin of the Chemical Society of Japan, 96(7), p.671 - 676, 2023/07

 Times Cited Count:5 Percentile:61.67(Chemistry, Multidisciplinary)

We investigated the distribution mechanism of Eu(III) in a single polymer-coated silica particle including nitrilotriacetamide (NTA) extractants known as HONTA and TOD2EHNTA. The present study provides a valuable approach for the evaluation and enhancement of the functionality of "single extractant-impregnated polymer-coated silica particle".

Journal Articles

Estimation for mass transfer coefficient under two-phase flow conditions using two gas components

Nanjo, Kotaro; Shiotsu, Hiroyuki; Maruyama, Yu; Sugiyama, Tomoyuki; Okamoto, Koji*

Journal of Nuclear Science and Technology, 60(7), p.816 - 823, 2023/07

 Times Cited Count:0 Percentile:0.00(Nuclear Science & Technology)

Journal Articles

Large-eddy simulation on gas mixing induced by the high-buoyancy flow in the CIGMA facility

Abe, Satoshi; Shibamoto, Yasuteru

Nuclear Engineering and Technology, 55(5), p.1742 - 1756, 2023/05

 Times Cited Count:0 Percentile:0.00(Nuclear Science & Technology)

Journal Articles

Experimental investigation of natural convection and gas mixing behaviors driven by outer surface cooling with and without density stratification consisting of an air-helium gas mixture in a large-scale enclosed vessel

Abe, Satoshi; Hamdani, A.; Ishigaki, Masahiro*; Shibamoto, Yasuteru

Annals of Nuclear Energy, 166, p.108791_1 - 108791_18, 2022/02

 Times Cited Count:6 Percentile:60.59(Nuclear Science & Technology)

Journal Articles

Study on chemisorption model of cesium hydroxide onto stainless steel type 304

Nakajima, Kunihisa; Nishioka, Shunichiro*; Suzuki, Eriko; Osaka, Masahiko

Mechanical Engineering Journal (Internet), 7(3), p.19-00564_1 - 19-00564_14, 2020/06

A large amount of cesium (Cs) chemisorbed onto stainless steel is predicted to be present especially in the upper region of reactor pressure vessel (RPV) during light water reactor severe accident (LWR SA) and a chemisorption model was developed for estimation of such amounts of Cs for stainless steel type 304 (SS304). However, this existing chemisorption model cannot accurately reproduce experimental results. Therefore, in this study, a modified Cs chemisorption model which accounts for silicon content in SS304 and concentration of cesium hydroxide (CsOH) in gaseous phases was constructed by combining penetration theory for gas-liquid mass transfer with chemical reaction and mass action law for CsOH decomposition at interface between gaseous and solid phases. As a result, it was found that the modified model was able to reproduce the experimental data more accurately than the existing model.

Journal Articles

Mass transfer inside narrow crevice of SUS316L in high temperature water

Yamamoto, Masahiro; Soma, Yasutaka; Igarashi, Takahiro; Ueno, Fumiyoshi

Proceedings of Annual Congress of the European Federation of Corrosion (EUROCORR 2018) (USB Flash Drive), 7 Pages, 2018/09

In order to clarify the SCC behavior of SUS316L under BWR environment, mass transfer inside crevice of SUS316L in high temperature water using various crevice gap samples was investigated. The samples were prepared by put together two SUS316L sheets. Crevice gap differs from 0.005 mm to 0.1 mm. Corrosion tests were conducted in 8 ppm dissolved oxygen (DO) conditions. Surface oxide film was analysed by laser Raman spectroscopy (LRS) after immersion. Numerical simulations were also conducted by using COMSOL Maltiphysics. Diffusion process of DO and the other chemical species were calculated with connected to electrochemical process. Electrical conductivities inside the crevice were 100 times larger than these of outer water. The reason of high conductivity is existence of Fe$$^{2+}$$ ions at the DO depletion crevice.

Journal Articles

Study of fission using multi-nucleon transfer reactions

Nishio, Katsuhisa; Hirose, Kentaro; L$'e$guillon, R.*; Makii, Hiroyuki; Orlandi, R.; Tsukada, Kazuaki; Smallcombe, J.*; Chiba, Satoshi*; Aritomo, Yoshihiro*; Tanaka, Shoya*; et al.

Proceedings of 6th International Conference on Fission and Properties of Neutron-rich Nuclei (ICFN-6), p.590 - 597, 2017/11

Journal Articles

Fission fragments mass distributions of nuclei populated by the multinucleon transfer channels of the $$^{18}$$O + $$^{232}$$Th reaction

L$'e$guillon, R.; Nishio, Katsuhisa; Hirose, Kentaro; Makii, Hiroyuki; Nishinaka, Ichiro*; Orlandi, R.; Tsukada, Kazuaki; Smallcombe, J.*; Chiba, Satoshi*; Aritomo, Yoshihiro*; et al.

Physics Letters B, 761, p.125 - 130, 2016/10

 Times Cited Count:43 Percentile:92.63(Astronomy & Astrophysics)

JAEA Reports

Verification and validation of the THYTAN code for the graphite oxidation analysis in the HTGR systems

Shimazaki, Yosuke; Isaka, Kazuyoshi; Nomoto, Yasunobu; Seki, Tomokazu; Ohashi, Hirofumi

JAEA-Technology 2014-038, 51 Pages, 2014/12

JAEA-Technology-2014-038.pdf:3.84MB

The analytical models for the evaluation of graphite oxidation were implemented into the THYTAN code, which employs the mass balance and a node-link computational scheme to evaluate tritium behavior in the High Temperature Gas-cooled Reactor (HTGR) systems for hydrogen production, to analyze the graphite oxidation during the air or water ingress accidents in the HTGR systems. This report describes the analytical models of the THYTAN code in terms of the graphite oxidation analysis and its verification and validation (V&V) results. Mass transfer from the gas mixture in the coolant channel to the graphite surface, diffusion in the graphite, graphite oxidation by air or water, chemical reaction and release from the primary circuit to the containment vessel by a safety valve were modeled to calculate the mass balance in the graphite and the gas mixture in the coolant channel. The computed solutions using the THYTAN code for simple questions were compared to the analytical results by a hand calculation to verify the algorithms for each implemented analytical model. A representation of the graphite oxidation experimental was analyzed using the THYTAN code, and the results were compared to the experimental data and the computed solutions using the GRACE code, which was used for the safety analysis of the High Temperature Engineering Test Reactor (HTTR), in regard to corrosion depth of graphite and oxygen concentration at the outlet of the test section to validate the analytical models of the THYTAN code. The comparison of THYTAN code results with the analytical solutions, experimental data and the GRACE code results showed the good agreement.

JAEA Reports

Manufacture of high-speed neutral atomic and molecular beam apparatus and its characterization

Hachiue, Shunsuke; Teraoka, Yuden

JAERI-Tech 2004-066, 69 Pages, 2004/11

JAERI-Tech-2004-066.pdf:7.44MB

In order to progress chemical reaction studies at verious material surfaces using high speed and reactive ions and neutral particles beams, a high-speed neutral atomic and molecular beam apparatus has been developed. In this report, details of the apparatus and characteristics of actually-generated oxygen atomic and molecular ion/neutral beams are discribed. This apparatus is a ultra-high vacuum system consisting of a plasma ion source, electrostatic lens systems, a mass separator, and a charge transfer chamber. Total oxygen ion currents of 52 microamps at accerelation energy of 8 keV and 17 microamps even at 20 eV were obtained. Mass separation was also good so that an oxygen molecular ion beam of 11 microamps and an oxygen atomic ion beam of 5.5 microamps were obtained even at 20 eV. A neutral oxygen atomic or molecular beam was also generated with the flux density of 10$$^{12}$$ particles/cm$$^{2}$$/s.

Journal Articles

Research and development on lead-bismuth technology for accelerator-driven transmutation system at JAERI

Kurata, Yuji; Kikuchi, Kenji; Saito, Shigeru; Kamata, Kinya*; Kitano, Teruaki*; Oigawa, Hiroyuki

Proceedings of 4th International Workshop on the Utilisation and Reliability of High Power Proton Accelerators, p.267 - 277, 2004/05

R&D on lead-bismuth technology have been conducted for accelerator driven system. From the test results of 316SS using JLBL-1 for 3000h without active oxygen control, mass transfer from high temperature to low temperature parts was observed. It was found that deposition of Pb/Bi and Fe-Cr grains in the annular channel of the electro-magnetic pump caused plugging and decrease in flow rate. The modification of the loop system brought about a good effect on operation. Significant erosion/corrosion was not observed in the experiment using MES loop for 1000h under 10$$^{-5}$$wt.% oxygen condition. The results of static corrosion tests showed the following: corrosion depth decreased at 450$$^{circ}$$C with increasing Cr content in steels while corrosion depth of JPCA and 316SS became larger due to ferritization caused by dissolution of Ni and Cr at 550$$^{circ}$$C. Si-added steel exhibited good corrosion resistance at 550$$^{circ}$$C.

Journal Articles

Dosimetry systems for 5-20MeV/amu heavy charged particle beams

Kojima, Takuji; Sunaga, Hiromi; Takizawa, Haruki; Tachibana, Hiroyuki

IAEA-TECDOC-1070, p.197 - 202, 1999/03

no abstracts in English

Journal Articles

A Steady-state simulation model of gas separation system by hollow-filament type membrane module

Iwai, Yasunori; Yamanishi, Toshihiko; Nishi, Masataka

Journal of Nuclear Science and Technology, 36(1), p.95 - 104, 1999/01

 Times Cited Count:12 Percentile:66.16(Nuclear Science & Technology)

no abstracts in English

JAEA Reports

Construction and Operation of the Vapor Compression Evaporator Treatment Facility

; ; ; ; ;

JAERI-M 9910, 37 Pages, 1982/01

JAERI-M-9910.pdf:1.57MB

no abstracts in English

JAEA Reports

PLATO: A Computer Code for the Analysis of Fission Product Plateout in HTGRs

Suzuki, Katsuo;

JAERI-M 9264, 28 Pages, 1981/01

JAERI-M-9264.pdf:0.83MB

no abstracts in English

28 (Records 1-20 displayed on this page)