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Yamagishi, Isao; Hato, Shinji*; Nishihara, Kenji; Tsubata, Yasuhiro; Sagawa, Yusuke*
JAEA-Data/Code 2024-002, 63 Pages, 2024/07
Adsorption columns filled with zeolite are used to treat contaminated water containing radioactive cesium generated by the Fukushima Daiichi Nuclear Power Station accident. As the contaminated water treatment progresses, the radioactive cesium in the adsorption column becomes highly concentrated, and the adsorption column becomes a high radiation source. To evaluate the radiation effects such as decay heat and radiolytic hydrogen production in the adsorption column, the concentration of radioactive cesium in the adsorption column is necessary, but since it is difficult to evaluate the concentration by measurement, it is estimated by simulation. In this research, a zeolite column adsorption dynamics simulation (Zeolite Adsorption Column: ZAC) code was developed to calculate the concentration of radioactive materials such as radioactive cesium in a zeolite filled adsorption column when they are injected into the column. The code was validated through comparison of calculation results with existing codes and experimental results of small column tests. This report presents the details of the model, the handling of the code, and the validity of the results for the developed code.
Takahatake, Yoko; Shibata, Atsuhiro; Nomura, Kazunori; Sato, Tsutomu*
Minerals (Internet), 7(12), p.247_1 - 247_13, 2017/12
Times Cited Count:9 Percentile:41.90(Geochemistry & Geophysics)Hydrous sodium titanate (SrTreat) is able to remove radioactive Sr from Radioactive contaminated water at Fukushima Daiichi Nuclear Power station (F1NPS). Knowing the amount of radioactive nuclides in the used SrTreat is important for an effective disposal and deposition of the F1NPS waste. This study investigated changes in the ability of SrTreat to sorb Sr during its use, and to understand the causes of changes in the sorbing. After exposure to a simulated treated water for 99 h, the surface structure of the SrTreat was changed, and the percentage of sorbed Sr and the buffer capacity for protons decreased. When the amount of radioactive nuclides contained in the used SrTreat is calculated from the sorption data of the as received SrTreat.
Kumagai, Yuta
Hoshasen Kagaku (Internet), (99), p.53 - 56, 2015/04
Radiation-induced degradation of 2-chlorophenol (2-ClPh) in zeolite/water mixtures was studied in order to consider a possibility of adsorption on zeolites to improve efficiencies of irradiation treatments of water contaminated by organic compounds. The degradation of 2-ClPh by -ray irradiation was investigated as a model compound. The degradation was evaluated by chloride ion (Cl
) production. A high concentration of Cl
was observed after the irradiation of a mixture with a mordenite-type zeolite (NaMOR), whereas A-type and X-type zeolites showed no significant effect. Therefore, for the mixture with NaMOR, effects of pH of the solution and of the 2-ClPh concentration were examined. At pH 5.7, the excess production of Cl
was induced by the addition of NaMOR. Concurrently, adsorption of 2-ClPh on NaMOR was observed. When the mixture contained a higher concentration of 2-ClPh at pH 5.7, the Cl
production increased. The adsorption of 2-ClPh also increased with increasing concentration. The results suggest that organics adsorbed on zeolites are decomposed by irradiation effectively at high adsorption concentrations.
Ikeda, Takashi
Journal of Chemical Physics, 141(4), p.044501_1 - 044501_8, 2014/07
Times Cited Count:17 Percentile:53.39(Chemistry, Physical)From both the polarized and depolarized Raman scattering spectra of supercritical water a peak located at around 1600 cm, attributed normally to bending mode of water molecules, was experimentally observed to vanish, whereas the corresponding peak remains clearly visible in the measured infrared (IR) absorption spectrum. In this computational study a theoretical formulation for analyzing the IR and Raman spectra is developed via first principles molecular dynamics combined with the modern polarization theory. We demonstrate that the experimentally observed peculiar behavior of the IR and Raman spectra for water are well reproduced in our computational scheme. We discuss the origins of a feature observed at 1600 cm
in Raman spectra of ambient water.
Yoshida, Yoichi*; Yang, J.*; Kondo, Takafumi*; Seki, Shuhei*; Kozawa, Takahiro*; Tagawa, Seiichi*; Shibata, Hiromi*; Taguchi, Mitsumasa; Kojima, Takuji; Namba, Hideki
JAEA-Review 2005-001, TIARA Annual Report 2004, p.183 - 185, 2006/01
A heavy-ion-pulse radiolysis technology was developed using a single-photon-counting system. In the system, the ion beam was injected a thin scintillator before irradiating the sample. The light emitted from the scintillator by the ion irradiation was used as analyzing source to detect the absorption of primary species in water. Measurement of time-dependent absorption of hydrated electrons in water was achieved using the system, which demonstrates the usefulness of this technique.
Seko, Noriaki; Katakai, Akio; Hasegawa, Shin; Tamada, Masao; Kasai, Noboru; Takeda, Hayato*; Sugo, Takanobu; Saito, Kyoichi*
Nuclear Technology, 144(2), p.274 - 278, 2003/11
Times Cited Count:143 Percentile:98.89(Nuclear Science & Technology)The total amount of uranium dissolved in seawater at a uniform concentration of 3 mg-U/m in the world's oceans is 4.5 billion tons. An adsorption method using polymeric adsorbents capable of specifically recovering uranium from seawater is reported to be economically feasible. A uranium-specific non-woven fabric was used as the adsorbent packed in an adsorption cage. We submerged adsorption cages, 16 m
in cross-sectional area and 16 cm in height, in the Pacific Ocean at a depth of 20 m at 7 km offshore of Japan. The cage consisted of stacks of 52,000 sheets of the uranium-specific non-woven fabric with a total mass of 350 kg. The total amount of uranium recovered by the non-woven fabric was more than one kg in terms of yellow cake during a total submersion time of 240 days in the ocean.
Konno, Chikara; Maekawa, Fujio; Kasugai, Yoshimi; Uno, Yoshitomo; Kaneko, Junichi; Nishitani, Takeo; Wada, Masayuki*; Ikeda, Yujiro; Takeuchi, Hiroshi
Nuclear Fusion, 41(3), p.333 - 337, 2001/03
Times Cited Count:3 Percentile:10.66(Physics, Fluids & Plasmas)no abstracts in English
Kimura, Hideo
JAERI-M 92-115, 48 Pages, 1992/08
no abstracts in English
; ; ;
Journal of Nuclear Science and Technology, 22(10), p.833 - 840, 1985/00
Times Cited Count:3 Percentile:46.66(Nuclear Science & Technology)no abstracts in English
;
Radioisotopes, 34(6), p.266 - 269, 1985/00
no abstracts in English
Saeki, Masakatsu; Hirabayashi, Takakuni
Radioisotopes, 33(11), p.775 - 779, 1984/00
no abstracts in English
; ; ; ; ; Yoshida, Kenzo
JAERI-M 83-072, 35 Pages, 1983/05
no abstracts in English
Fujimura, Takashi; Kaetsu, Isao
Appl.Biochem.Biotechnol., 8, p.145 - 151, 1983/00
Times Cited Count:14 Percentile:48.09(Biochemistry & Molecular Biology)no abstracts in English
Yamamoto, Katsumune; Nakazaki, Chozaburo; Okagawa, Seigo; Yokouchi, Iichiro;
Journal of Nuclear Science and Technology, 17(1), p.67 - 76, 1980/00
Times Cited Count:1 Percentile:22.51(Nuclear Science & Technology)no abstracts in English
; Tachikawa, Enzo;
Journal of Nuclear Science and Technology, 16(3), p.200 - 206, 1979/00
no abstracts in English
; Tachikawa, Enzo;
Nuclear Technology, 42(2), p.172 - 179, 1979/00
Times Cited Count:4no abstracts in English
; Tachikawa, Enzo; ;
Annals of Nuclear Energy, 5(1), p.5 - 12, 1978/01
Times Cited Count:13no abstracts in English
; ;
Journal of Nuclear Science and Technology, 10(5), p.292 - 300, 1973/05
no abstracts in English
Tachi, Yukio; Yotsuji, Kenji; Ito, Tsuyoshi; Suyama, Tadahiro
no journal, ,
The integrated sorption and diffusion (ISD) model was applied for systems coexisting multispecies Sr (divalent cation Sr and neutral SrSO
(aq)) in compacted montmorillonite. Effective diffusion coefficients (De) and distribution coefficients (Kd) of Sr in compacted Na-montmorillonite (dry density of 800 kg/m
) saturated with three types of Na
SO
solutions (0.05, 0.1, 0.5 M) were measured by the trough-diffusion method. The De and Kd values decreased drastically with increasing porewater salinity. The De for multispecies Sr was determined as the harmonic weight-average considering the two species distribution and their log De values, based on comparison with reactive-transport calculations using the PHREEQC. As a result, the De trend could be quantitatively express by the ISD model considering multispecies contributions. The thermodynamic sorption model considering ion exchange reactions could provide reasonable account of Kd trend as functions of salinity.
Kumagai, Yuta
no journal, ,
no abstracts in English