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Journal Articles

Discovery of ion-adsorption type deposits of rare earth elements (REE) in Southwest Japan with speciation of REE by extended X-ray absorption fine structure spectroscopy

Yamaguchi, Akiko*; Honda, Tasuku*; Tanaka, Masato*; Tanaka, Kazuya; Takahashi, Yoshio*

Geochemical Journal, 52(5), p.415 - 425, 2018/00

 Times Cited Count:3 Percentile:59.14(Geochemistry & Geophysics)

Ion-adsorption type REE deposits in weathered granite are main sources of REE essential for high-technology industries. However, these type deposits have not been searched in Japan. In this study, Bulk REE abundances (= REE$$_{TOT}$$), ion-exchangeable REE (= REE$$_{EX}$$) by ammonium chloride solution, and percentage of REE$$_{EX}$$ relative to REE$$_{TOT}$$ (= REE$$_{PER}$$) in fresh and weathered granite samples in Southwest Japan (i.e., Hiroshima and Shimane Prefectures) were determined. The REE$$_{TOT}$$ and REE$$_{PER}$$ were comparable to those of ion-adsorption type REE deposits in China. Extended X-ray adsorption fine structure (EXAFS) spectra of REE in original samples and samples after the extraction of ion-exchangeable REE showed that (i) REE in samples with high REE$$_{PER}$$ mainly forms outer-sphere complexes and (ii) the remaining REE in the rocks after the extraction forms inter-sphere complexes.

Journal Articles

Characterization of rare earth elements (REEs) associated with suspended particles in deep granitic groundwater and their post-closure behavior from a simulated underground facility

Iwatsuki, Teruki; Munemoto, Takashi*; Kubota, Mitsuru*; Hayashida, Kazuki; Kato, Toshihiro*

Applied Geochemistry, 82, p.134 - 145, 2017/05

AA2017-0090.pdf:2.35MB

 Times Cited Count:2 Percentile:79.82(Geochemistry & Geophysics)

This study investigated the behavior of rare earth elements (REEs) associated with suspended particles in deep granitic groundwater and in a sealed drift at a depth of 500 m in the Mizunami Underground Research Laboratory (URL) in Japan. Approximately 10%$$sim$$60% of REEs in groundwater are associated with suspended particles. Carbonate particles in groundwater are most likely derived from in situ precipitation of supersaturated carbonate minerals such as calcite. Thermodynamic calculations show that the dissolved REE carbonate complexes in the closed drift decreased in the drift closure period. These complexes may have been absorbed or co-precipitated within the shotcrete on the drift wall. The usage of cement based materials would generate environmental conditions in which REEs are fundamentally immobile in and around the underground facilities.

Journal Articles

Interaction of rare earth elements and components of the Horonobe deep groundwater

Kirishima, Akira*; Kuno, Atsushi*; Amamiya, Hiroki; Kubota, Takumi*; Kimuro, Shingo*; Amano, Yuki; Miyakawa, Kazuya; Iwatsuki, Teruki; Mizuno, Takashi; Sasaki, Takayuki*; et al.

Chemosphere, 168, p.798 - 806, 2017/02

 Times Cited Count:1 Percentile:92.28(Environmental Sciences)

For better understanding of the migration behavior of minor actinides (MA) in deep groundwater, the interaction of doped rare earth elements (REEs) and components in Horonobe deep groundwater was studied. Appx. 10 ppb of rare earth elements, i.e., Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er, Tm and Yb were doped to the sample groundwater collected from a packed sections in borehole drilled from 140 m depth experiment drift of Horonobe underground research laboratory (URL), Hokkaido, Japan. Then, that groundwater was sequentially filtrated by 0.2 micron pore filter, 10 kDa, 3 kDa and 1 kDa of nominal molecular weight limit (NMWL) ultrafilters by keeping inert condition. After that, the filtrate solutions were analyzed by ICP-MS to determine the concentrations of retained REEs at each filtration steps, while the used filters were analyzed by the neutron activation analysis (NAA) and TOF-SIMS element mapping to know the amount and chemical speciation of trapped fraction of the REEs on each filter. A remarkable relation between the retention ratios of REEs in the filtrate solutions and the ionic radius was observed, i.e., smaller rare earth element solves more in liquid phase under the Horonobe groundwater condition. NAA and TOF-SIMS analyses revealed that certain portions of REEs were trapped by 0.2 micron pore filters as rare earth phosphates which corresponded with the predicted predominant species by a chemical equilibrium calculation for the Horonobe groundwater condition, while small portions of colloidal REEs were trapped by 10 kDa and 3 kDa NMWL ultrafilters. The result suggested that phosphate anion plays an important role in the chemical behavior of REEs in saline (seawater based) groundwater, which could be referred for the prediction of migration behavior of trivalent actinide released from the repository of radioactive waste in far future.

Journal Articles

Retention of rare earth elements, thorium and uranium in sedimentary rocks; A Case study in the Horonobe area of Hokkaido, Japan

Murakami, Takuma; Sasamoto, Hiroshi; Mizuno, Takashi

Chikyu Kagaku, 50(4), p.299 - 317, 2016/12

Development of techniques for investigating the long-term migration of elements in deep underground is important with respect to safety assessment for the geological disposal of high-level radioactive waste. As one study of the migration of elements in deep underground, the distribution of REE, Th and U in sedimentary rock of Horonobe area in Hokkaido was investigated, and discussed whether the difference of hydrogeological structure and lithofacies influences on the distributions. As the results, it was considered that REE and Th were mainly retained in minerals originating from terrigenous clastic and secondary mineral occurred in early diagenesis, and their distributions were relatively homogenous in both the Koetoi and Wakkanai formations. Uranium was indicated to be maintained in the sedimentary rock until now after depositing in deep-sea sediment. It was considered that the U deposition was occurred by adsorption on organic matter and reductive precipitation with decomposition of organic matter. In addition, it was confirmed that the distributions of these elements were not influenced by the difference of hydrogeological and lithofacies.

Journal Articles

Simultaneous recovery and separation of rare earth elements in ferromanganese nodules by using ${{it Shewanella putrefaciens}}$

Fujimoto, Jun*; Tanaka, Kazuya; Watanabe, Naoko*; Takahashi, Yoshio*

Hydrometallurgy, 166, p.80 - 86, 2016/12

 Times Cited Count:4 Percentile:63.57(Metallurgy & Metallurgical Engineering)

We examined recovery of REEs in Fe-Mn nodules by using ${{it Shewanella putrefaciens}}$ (Fe-reducing bacterium). In this method, Fe-Mn nodule decomposition and REE recovery were achieved simultaneously in a single solution system. Fe-Mn nodules were reductively decomposed in NaCl solution under anaerobic conditions with daily addition of sodium lactate as an electron donor. During the decomposition of Fe-Mn nodule, REEs released from the Fe-Mn nodule were adsorbed on bacterial cells. Of the conditions studied here, the best REE adsorption rates were obtained with 0.5M NaCl solution at pH7 with daily addition of 1 mmol sodium lactate.

Journal Articles

Rare earth elements (REE) in deep groundwater from granite and fracture-filling calcite in the Tono area, central Japan; Prediction of REE fractionation in paleo- to present-day groundwater

Munemoto, Takashi; Omori, Kazuaki*; Iwatsuki, Teruki

Chemical Geology, 417, p.58 - 67, 2015/12

 Times Cited Count:17 Percentile:30.31(Geochemistry & Geophysics)

Rare earth elements (REEs) combined with yttrium (YREE) in deep groundwater from granite and fracture-filling calcite are being studied at the Mizunami Underground Research Laboratory (MIU, Tono area, central Japan).

Journal Articles

Interactions of rare earth elements with bacteria and organic ligands

Ozaki, Takuo; Suzuki, Yoshinori*; Nankawa, Takuya; Yoshida, Takahiro; Onuki, Toshihiko; Kimura, Takaumi; Francis, A. J.*

Journal of Alloys and Compounds, 408-412, p.1334 - 1338, 2006/02

 Times Cited Count:39 Percentile:12.61(Chemistry, Physical)

We investigated the interactions of Eu(III) with the common soil bacterium Pseudomonas fluorescens and organic ligands, such as malic acid, citric acid, and a siderophore (DFO). Malic acid formed complexes with Eu(III), but degradation of malic acid was observed when the ratio of malic acid to Eu(III) was high. Citric acid formed a stoichiometric complex with Eu(III) that was not degraded by P. fluorescens. Adsorption of Eu(III) from the DFO complex occurred as a free ion dissociated from DFO and not as the Eu(III)-DFO complex. Time-resolved laser-induced fluorescence spectroscopy analysis showed that adsorption of Eu(III) on P. fluorescens was through a multidentate and predominantly inner-spherical coordination.

Journal Articles

Adsorption of rare earth elements by $$gamma$$-Al$$_{2}$$O$$_{3}$$ and ${it Pseudomonas fluorescens}$ cells in the presence of desferrioxamine B; Implication of siderophores for the Ce anomaly

Yoshida, Takahiro; Ozaki, Takuo; Onuki, Toshihiko; Francis, A. J.*

Chemical Geology, 212(3-4), p.239 - 246, 2004/12

 Times Cited Count:39 Percentile:35.69(Geochemistry & Geophysics)

no abstracts in English

Journal Articles

Lithogenic flux in the Japan Sea measured with sediment traps

Otosaka, Shigeyoshi; Togawa, Orihiko; Baba, Masami*; Karasev, E.*; Volkov, Y. N.*; Omata, Nobutaka*; Noriki, Shinichiro*

Marine Chemistry, 91(1-4), p.143 - 163, 2004/11

 Times Cited Count:34 Percentile:30.78(Chemistry, Multidisciplinary)

Spatial and temporal variations of particulate flux were observed by sediment trap experiments at three areas of the Japan Sea (western Japan Basin, eastern Japan Basin and Yamato Basin) during 1999-2002. Mass flux in the Japan Sea showed remarkable regional distribution. Annual mean mass flux at 1 km depth was 455 mg/m$$_{2}$$/day in the eastern Japan Basin, 252 mg/m$$_{2}$$/day in the eastern Japan Basin and 147 mg/m$$_{2}$$/day in the Yamato Basin. Mass fluxes were especially large in spring (March-May). From the distribution of elemental abundance in sediments, La/Yb and Mn/Al ratios as indicators of the origin of aluminosilicates and the "freshness" of particles, respectively. These proxies suggested three sources of lithogenic material for the Japan Sea, (1) atmospheric input of Kosa particles, (2) lateral transport from the East China Sea, and (3) lateral transport from Island-Arc such as the Japan Islands.

Journal Articles

Photoluminescent dinuclear lanthanide complexes with Tris(2-pyridyl)carbinol acting as a new tetradentate bridging ligand

Watanabe, Masayuki; Nankawa, Takuya*; Yamada, Teppei*; Kimura, Takaumi; Namiki, Kosuke*; Murata, Masaki*; Nishihara, Hiroshi*; Tachimori, Shoichi

Inorganic Chemistry, 42(22), p.6977 - 6979, 2003/11

 Times Cited Count:33 Percentile:23.18(Chemistry, Inorganic & Nuclear)

A tripodal ligand, tris(2-pyridyl)carbinol affords a novel tetradentate coordination mode in homodinuclear lanthanide complexes, which exhibit remarkably short distance between the metal ions. Strong fluorescence of Eu(III) and Tb(III) complexes with the ligand demonstrate that the ligand has a suitable excited state for energy transfer from the ligand to Eu(III) and Tb(III) center.

Journal Articles

Separation of americium(III) from lanthanide by encapsulating hexadentate-ligand

Watanabe, Masayuki; Mirvaliev, R.*; Tachimori, Shoichi; Takeshita, Kenji*; Nakano, Yoshio*; Morikawa, Koshi*; Mori, Ryohei*

Chemistry Letters, 31(12), p.1230 - 1231, 2002/12

Encapsulative semi-podand type ligand, N, N, N', N' #8211; tetrakis(2-methylpyridyl)ethylenediamine (TPEN) gives good selectivity of Am(III) over trivalent lanthanide by solvent extraction. This is the first robust extraction system which can separate Am(III) from trivalent lanthanide.

Journal Articles

Effect of alloy composition on photoluminescence properties of europium implanted AlGaInN

Nakanishi, Yasuo*; Wakahara, Akihiro*; Okada, Hiroshi*; Yoshida, Akira*; Oshima, Takeshi; Ito, Hisayoshi

Physica Status Solidi (C), 0(1), p.461 - 464, 2002/12

no abstracts in English

Journal Articles

Photoluminescence properties of Eu-doped GaN by ion implantation

Nakanishi, Yasuo*; Wakahara, Akihiro*; Yoshida, Akira*; Oshima, Takeshi; Ito, Hisayoshi; Sakai, Shiro*

IPAP Conference Series 1 (Proceedings of International Workshop on Nitride Semiconductors), p.486 - 489, 2000/11

no abstracts in English

Journal Articles

Extraction of lanthanide and actinide elements by thermosensitive polymer gel copolymerized with acidic phosphorus compound

Takeshita, Kenji*; Nakano, Yoshio*; Matsumura, Tatsuro

Kagaku Kogaku Shimpojiumu Sirizu 74; Kinzoku No Risaikuru Oyobi Kankyo Mondai, p.89 - 95, 2000/05

no abstracts in English

JAEA Reports

None

Yamanaka, Shinsuke*; Abe, Kazuyuki

JNC-TY9400 2000-004, 78 Pages, 2000/03

JNC-TY9400-2000-004.pdf:2.39MB

no abstracts in English

Journal Articles

Development of a compact atomic beam flux monitor based on surface ionization

Tamura, Koji; ; Adachi, Hajime; Shibata, Takemasa; Oba, Hironori

Japanese Journal of Applied Physics, Part 1, 37(12A), p.6651 - 6654, 1998/12

 Times Cited Count:0 Percentile:100(Physics, Applied)

no abstracts in English

JAEA Reports

None

Goto, Masahiro*

PNC-TJ1606 98-001, 79 Pages, 1998/03

PNC-TJ1606-98-001.pdf:2.1MB

no abstracts in English

JAEA Reports

None

PNC-TJ1601 98-004, 16 Pages, 1998/03

PNC-TJ1601-98-004.pdf:3.05MB

no abstracts in English

JAEA Reports

Measurements of atomic beam flux of rare earth elements by means of surface ionization

Tamura, Koji; Adachi, Hajime; Shibata, Takemasa

JAERI-Research 98-020, 13 Pages, 1998/03

JAERI-Research-98-020.pdf:0.66MB

no abstracts in English

Journal Articles

Hydrothermal redistribution of rare earth elements in Toki granitic rock,central Japan

; Onuki, Toshihiko; Isobe, Hiroshi; Yanase, Nobuyuki; Sekine, Keiichi; *; *

Journal of Contaminant Hydrology, 35, p.191 - 199, 1998/00

 Times Cited Count:4 Percentile:80.08(Environmental Sciences)

no abstracts in English

78 (Records 1-20 displayed on this page)