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JAEA Reports

Structural investigation of borosilicate glasses by using XAFS measurement in Soft X-ray region (Joint research)

Nagai, Takayuki; Okamoto, Yoshihiro; Yamagishi, Hirona*; Ota, Toshiaki*; Kojima, Kazuo*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*

JAEA-Research 2021-010, 62 Pages, 2022/01

JAEA-Research-2021-010.pdf:6.05MB

The local structure of glass-forming elements and waste elements in borosilicate glasses varies with its chemical composition. In this study, borosilicate glass frit and simulated waste glass samples were prepared and the local structure and chemical state regarding boron(B), oxygen(O), silicon(Si) and waste elements of iron(Fe), cesium(Cs) were estimated by using XAFS measurement in soft X-ray region. Following results were obtained by XAFS measurements of prepared glass frit and simulated waste glass samples: (1) The effect of Na $_{2}$ O concentration on B-O coordination structure is greater than that of the waste elements concentration. (2) The height of pre-edge by O K-edge spectrum depends on the concentration of first transition elements such as Fe in glass samples. Following results were obtained by XAFS measurements of simulated waste glass samples after immersion test to investigate the long chemical stability. (1) A new compound was formed on the sample surface after the immersion test, and changes in the surface state were confirmed by Raman spectroscopy. (2) Cs on the sample surface after immersion test dissolves into the leaching solution. The Si K-edge XANES spectra of borosilicate glass frits and simulated waste glass samples included lanthanides oxide were measured, and following was confirmed. (1) As the Na $_{2}$ O concentration increases in borosilicate glass frit, the K-edge peak of Si shifts to the low energy side. (2) The peak height of the K-edge of Si differs depending on the kind of lanthanide.

Journal Articles

Soil microbial community responding to moderately elevated nitrogen deposition in a Japanese cool temperate forest surrounded by fertilized grasslands

Nagano, Hirohiko; Nakayama, Masataka*; Katata, Genki*; Fukushima, Keitaro*; Yamaguchi, Takashi*; Watanabe, Makoto*; Kondo, Toshiaki*; Atarashi-Andoh, Mariko; Kubota, Tomohiro*; Tateno, Ryunosuke*; et al.

Soil Science and Plant Nutrition, 67(5), p.606 - 616, 2021/10

https://doi.org/10.1080/00380768.2021.1974799

Times Cited Count：2 Percentile：19.73(Plant Sciences)

We analyzed the relationships between nitrogen deposition (deposition of nitrate and ammonium ions) and soil microbial properties in a cool temperate forest surrounded by normally fertilized pasture grasslands in northern Japan. The aim of the present study was to gain the primary information on soil microbial response to moderately elevated nitrogen deposition ( 10 kg N ha $^{-1}$ y $^{-1}$ ). We established three experimental plots in the forest edge adjacent to grasslands and other three plots in the forest interior at least 700 m away from the grasslands. During May to November 2018, nitrogen deposition in each plot was measured. In August 2018, litter and soil (0-5 cm depth) samples were collected from all plots to measure net nitrogen mineralization and nitrification rates as indicators of microbial activity, and microbial biomass carbon and nitrogen and various gene abundances (i.e. bacterial 16S rRNA, fungal ITS, bacterial amoA, and archaeal amoA genes) as indicators of microbial abundance and structure. Nitrogen deposition in the forest edge was 1.4-fold greater than that in the forest interior, even while the maximum deposition was 3.7 kg N ha $^{-1}$ . Nitrogen deposition was significantly correlated to the net nitrogen mineralization and nitrification rates and the 16S rRNA and bacterial amoA gene abundances. Microbial community structures were different between litter and soil samples but were similar between the forest edge and interior. Significant correlations of nitrogen deposition to the soil carbon to nitrogen ratio, and the nitrate and ammonium contents were also observed. Thus, our results show that moderately elevated nitrogen deposition in nitrogen-limited forest edges can stimulate microbial activities and abundances in soils.

JAEA Reports

Structural investigation of simulated waste glass samples by using XAFS measurement in soft X-ray region (Joint research)

Nagai, Takayuki; Okamoto, Yoshihiro; Yamagishi, Hirona*; Ota, Toshiaki*; Kojima, Kazuo*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*

JAEA-Research 2020-009, 48 Pages, 2020/09

JAEA-Research-2020-009.pdf:4.53MB

The local structure of glass-forming elements and waste elements in waste glass varies with its chemical composition. In this study, borosilicate glass frit and simulated waste glass samples were prepared and the local structure and chemical state regarding boron (B), oxygen (O), and waste elements of cerium (Ce), cesium (Cs) were estimated by using XAFS measurement in soft X-ray region. Following results were obtained by XAFS measurements of prepared glass frit and simulated waste glass samples: (1) The existence ratio of four coordinate sp $^{3}$ structure (BO $_{4}$ ) tends to increase with increasing Na $_{2}$ O content in glass samples. (2) The height of a pre-edge which appears by K-edge XANES spectrum of O is so high that the Fe content in glass samples. Following results were obtained by XAFS measurements of simulated waste glass samples after immersion test to investigate long chemical stability. (1) The existence ratio of four coordinate sp $^{3}$ structure (BO $_{4}$ ) increases by immersion test. (2) Ce which exists in the surface layer is oxidized by immersion test, and much of Cs in surface layer is lost after leach testing. Even if the glass frit form (fiber cartridge or beads) and manufacturing method were changed and a glass sample of the similar chemical composition was prepared, these observed Raman spectra of samples were different.

Journal Articles

Porous metal-organic frameworks containing reversible disulfide linkages as cathode materials for lithium-ion batteries

Shimizu, Takeshi*; Wang, H.*; Matsumura, Daiju; Mitsuhara, Kei*; Ota, Toshiaki*; Yoshikawa, Hirofumi*

ChemSusChem, 13(9), p.2256 - 2263, 2020/05

https://doi.org/10.1002/cssc.201903471

Times Cited Count：24 Percentile：77.17(Chemistry, Multidisciplinary)

JAEA Reports

XAFS measurement of simulated waste glass samples (Joint research)

Nagai, Takayuki; Sasage, Kenichi; Okamoto, Yoshihiro; Shiwaku, Hideaki; Yamagishi, Hirona*; Ota, Toshiaki*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*; Takahashi, Tomoe*; et al.

JAEA-Research 2019-003, 94 Pages, 2019/09

JAEA-Research-2019-003.pdf:7.92MB

The local structures of glass-forming elements and waste elements would change by the chemical composition of waste glass including those elements. In this study, simulated waste glass samples were prepared from borosilicate glass frit including phosphorus (P) or vanadium (V), and we investigated local structures of boron, sodium, and waste elements in these P glass and V glass samples by using synchrotron XAFS measurements in soft and hard X ray region.

JAEA Reports

XAFS measurement of simulated waste glass samples prepared from borosilicate glass frit including phosphorus pentaoxide (Joint research)

Nagai, Takayuki; Kobayashi, Hidekazu; Shimamura, Keisuke; Oyama, Koichi; Sasage, Kenichi; Okamoto, Yoshihiro; Shiwaku, Hideaki; Yamanaka, Keisuke*; Ota, Toshiaki*

JAEA-Research 2018-005, 72 Pages, 2018/09

JAEA-Research-2018-005.pdf:28.2MB

Addition of radioactive waste to a borosilicate glass frit affects the local structures of glass-forming elements and waste elements in a waste glass produced in a vitrification process. In this study, simulated waste glass samples were prepared from borosilicate glass frit including phosphorus pentaoxide, and we investigated local structures of sodium (Na), boron (B), and waste elements in these glass samples by using synchrotron XAFS measurements in soft and hard X ray region.

Journal Articles

Rechargeable batteries based on stable redox reactions of disulfide included in a metal-organic framework as ligands

Shimizu, Takeshi*; Wang, H.*; Tanifuji, Naoki*; Matsumura, Daiju; Yoshimura, Masashi*; Nakanishi, Koji*; Ota, Toshiaki*; Yoshikawa, Hirofumi*

Chemistry Letters, 47(5), p.678 - 681, 2018/05

https://doi.org/10.1246/cl.180121

Times Cited Count：9 Percentile：33.87(Chemistry, Multidisciplinary)

Journal Articles

Local structure analysis of light elements included in simulated radioactive waste glasses by soft X-ray absorption fine structure

Okamoto, Yoshihiro; Nagai, Takayuki; Kaneko, Koji; Motokawa, Ryuhei; Haga, Yoshinori; Yamanaka, Keisuke*; Ota, Toshiaki*

2017-Nendo Seika Kokaigata Riyo Seika Hokokusho (Ritsumeikan Daigaku SR Senta), p.33 - 36, 2018/00

The high-level radioactive waste solution which generated from a spent nuclear fuel reprocessing process are mixed with a borosilicate glass frit in a vitrification process, and a chemical stable glass solidified body is produced. To understand local structure of light elements included in a glass solidified body, we carried out a B K-edge XANES measurement of raw glass frits and simulated radioactive waste glasses. As a result of this estimation of boron local structure in glass samples, it was found that the sp $^{3}$ type boron (BO $_{4}$ ) percentage increases and the sp $^{2}$ type (BO $_{3}$ ) percentage by increasing the sodium content in glass frits.

JAEA Reports

XAFS measurement of simulated waste borosilicate glass samples (Joint research)

Nagai, Takayuki; Kobayashi, Hidekazu; Sasage, Kenichi; Ayame, Yasuo; Okamoto, Yoshihiro; Shiwaku, Hideaki; Yamanaka, Keisuke*; Ota, Toshiaki*

JAEA-Research 2017-005, 54 Pages, 2017/06

JAEA-Research-2017-005.pdf:16.17MB

Addition of radioactive waste to a borosilicate frit affects the local structures of boron (B) and waste elements in a waste glass. Synchrotron XAFS measurement was applied to investigate the local structural changes by using simulated waste borosilicate glass samples. Following results were obtained by the B K-edge XAFS analysis. It was confirmed that B K-edge XAFS analysis enables us to discriminate sp $^{2}$ type boron (BO $_{3}$ ) from sp $^{3}$ type boron (BO $_{4}$ ). Addition of waste elements to a glass frit increases the percentage of BO $_{3}$ and decreases that of BO $_{4}$ . By decreasing the SiO $_{2}$ /Al $_{2}$ O $_{3}$ ratio or increasing the (SiO $_{2}$ +B $_{2}$ O $_{3}$ )/Al $_{2}$ O $_{3}$ ratio in the glass composition, the BO $_{3}$ percentage increases and the BO $_{4}$ percentage decreases. Addition of P $_{2}$ O $_{5}$ decreases the BO $_{3}$ percentage and increases the BO $_{4}$ percentage. Following results were obtained from XAFS measurement of the waste elements. Cerium (Ce) valence is more reduced with the increase of the B $_{2}$ O $_{3}$ content. Addition of P $_{2}$ O $_{5}$ has a tendency to reduce the Ce valence and to enhance deposition of Zr oxide. Deposition of ruthenium compounds separated from glass phase can not be improved by changing the B $_{2}$ O $_{3}$ content. This study was performed as a part of the project, "Improvement of vitrification process of high-level radioactive liquid wastes" on the foundation business of the Agency for Natural Resources and Energy.

Journal Articles

Vanadium uptake and an effect of vanadium treatment on $^{18}$ F-labeled water movement in a cowpea plant by positron emitting tracer imaging system (PETIS)

Furukawa, Jun*; Yokota, Harumi*; Tanoi, Keitaro*; Ueoka, Shiori*; Matsuhashi, Shimpei; Ishioka, Noriko; Watanabe, Satoshi; Uchida, Hiroshi*; Tsuji, Atsunori*; Ito, Takehito*; et al.

Journal of Radioanalytical and Nuclear Chemistry, 249(2), p.495 - 498, 2001/08

https://doi.org/10.1023/A:1013276224300

Times Cited Count：16 Percentile：73.21(Chemistry, Analytical)

We present real time Vanadate (V $^{5+}$ ) uptake imaging in a cowpea plant by Positron Emitting Tracer Imaging System (PETIS). Vanadium-48 was produced by bombarding a Sc foil target with 50 MeV -particles at Takasaki Ion accelerators for Advanced Radiation Application (TIARA) AVF cyclotron. Then $^{48}$ V was added to the culture solution to investigate the V distribution in a cowpea plant. The real time uptake of the $^{48}$ V was monitored by PETIS. We measured the distribution of $^{48}$ V in a whole plant after 3, 6 and 20 hours of V treatment by Bio-imaging Analyzer System (BAS). After the 20 hour treatment, vanadate was detected at the up-ground part of the plant. To know the effect of V uptake on plant activity, $^{18}$ F-labeled water uptake was analyzed by PETIS. When a cowpea plant was treated with V for 20 hours before $^{18}$ F-labeled water uptake experiment, the total amount of $^{18}$ F-labeled water absorption was drastically desreased. Results suggest the inhibition of water uptake was mainly caused by the vanadate already moved to the up-ground part of the plant.

Journal Articles

$^{18}$ F used as tracer to study water uptake and transport imaging of a cowpea plant

Nakanishi, Tomoko*; Tanoi, Keitaro*; Yokota, Harumi*; Kang, D.-J.*; Ishii, Ryuichi*; Ishioka, Noriko; Watanabe, Satoshi; Osa, Akihiko; Sekine, Toshiaki; Matsuhashi, Shimpei; et al.

Journal of Radioanalytical and Nuclear Chemistry, 249(2), p.503 - 507, 2001/08

https://doi.org/10.1023/A:1013217425209

We present the water uptake ability of cowpea () which has been regarded as one of the most drought resistant species among the pulse crops. It has been suggested that in the lower part of the stem, parenchymatous tissue for storing water had been developed for the function of deought resistance. We confirmed that in this tissue, water amount was high compared to the other stems by neutron radiography. Then the water uptake manner was measured by positron emitting tracer imaging system (PETIS) using $^{18}$ F labeled water produced by a cyclotron. Comparing the water uptake manner of cowpea plant with that of common bean, cowpea plant was found to maintain high water uptake activity after drying treatment, suggesting the high drought resistant character.

Journal Articles

Comparison of $^{15}$ O-labeled and $^{18}$ F-labeled water uptake in a soybean plant by PETIS (Positron Emitting Tracer Imaging System)

Nakanishi, Tomoko*; Yokota, Harumi*; Tanoi, Keitaro*; Ikeue, Natsuko*; Okuni, Yoko*; Furukawa, Jun*; Ishioka, Noriko; Watanabe, Satoshi; Osa, Akihiko; Sekine, Toshiaki; et al.

Radioisotopes, 50(6), p.265 - 269, 2001/06

https://doi.org/10.3769/radioisotopes.50.265

$^{15}$ O-Labeled and $^{18}$ F-Labeled water uptake manner in a soybean plant was compared by PETIS (Positron Emitting Tracer Imaging System). $^{15}$ O-Labeled water (half-life: 2 min) and $^{18}$ F-Labeled water (half-life: 110 min) were produced by a cyclotron by $^{14}$ N(d,n) $^{15}$ O and $^{16}$ O(,pn) $^{18}$ F reactions, respectively. A root of a soybean plant was cut off and each labeled water was supplied from the basal part of the plant. The gamma-rays emitted from the sample was measured by a BGO counter with a detection area of 5 cm15 cm. The radioactivity from each stem was accumlated every 15 s till 20 min. It was found that $^{18}$ F-labeled water was taken up much faster than $^{15}$ O-labeled water, suggesting that in $^{18}$ F-labeled water, fluorine was moved in the form of $^{18}$ F-ion. When BAS image of $^{15}$ O-labeled water in a plant after 5 min and 10 min of water supply was taken, it was found that the labeled water was observed only in the lowest internode, between a root and the first leaves.

Oral presentation

Coordination state investigation of borosilicate glass by the XAFS measurement of boron K-edge

Yamanaka, Keisuke*; Nagai, Takayuki; Ota, Toshiaki*

no journal, ,

For understanding the fundamental knowledge in the vitrification process of radioactive waste, the local structure of boron of simulated waste glass was investigated by using the XAFS measurement in BL-11 of Ritsumeikan University SR Center.

Oral presentation