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La(n,
)
La reactionEndo, Shunsuke; Fujioka, Hiroyuki*; Goto, Yu*; Ino, Takashi*; Iwamoto, Osamu; Iwamoto, Nobuyuki; Kawamura, Shiori*; Kimura, Atsushi; Kitaguchi, Masaaki*; Kobayashi, Ryuju; et al.
JPS Conference Proceedings (Internet), 45, p.011056_1 - 011056_8, 2026/06
Honda, Mitsunori; Kaneta, Yui; Muraguchi, Masakazu*; Hayakawa, Kosetsu*; Oda, Masato*; Iino, Chiaki*; Ishii, Hiroyuki*; Goto, Takuya*
AIP Advances (Internet), 14(5), p.055034_1 - 055034_6, 2024/05
Times Cited Count:5 Percentile:49.63(Nanoscience & Nanotechnology)This study examines the utilization of Fukushima weathered biotite(WB)as an alternative to conventional thermoelectric materials traditionally derived from rare and toxic substances. WB underwent milling, classification, and subsequent heat treatment via molten-salt treatment to produce crystals exhibiting conductivity akin to semiconductors within from 650
C to 850
C range. Evaluation of WB and the derived crystal's electrical conductivity and Seebeck coefficient showcased their viability for high-temperature thermoelectric applications. Consequently, WB attained a dimensionless figure of merit (ZT) of 0.015, signaling its potential as a thermoelectric material that surpasses 650
C.

Honda, Mitsunori; Goto, Takuya*; Sakanaka, Yoshihide*; Yaita, Tsuyoshi; Suzuki, Shinichi*
AIMS Electronics and Electrical Engineering (Internet), 3(2), p.102 - 110, 2019/03
The possibility of removal and controlling crystal formation from weathered biotite (WB) in clay minerals were investigated using molten salt electrochemistry (EC) in molten NaCl-CaCl
under an electrochemical reductive reaction. Cyclic Voltammogram (CV) measurements were performed in the range of +0.5 V to -2.2 V. Several peaks were confirmed in the CV spectra. The peak at -1.4 V represents a reduction reaction of Fe in WB, so we conducted an experiment at -1.4 V for 2 h to reduce Iron (Fe). The Cs removal rate after EC treatment was determined by X-ray fluorescence analysis, and almost 100% Cs removal was confirmed. To understand the effect of the reductive reaction, we performed X-ray Adsorption Fine Structure (XAFS) analysis. Before EC treatment, the Fe in WB was present as a mixture of Fe
and Fe
. After EC treatment, the presence of Fe
was confirmed by XAFS analysis. Based on this finding, EC treatment is effective for reducing Fe in WB. This result indicated that Fe
O
formation was suppressed, and the reduction reaction was effective for controlling crystal formation.
-rays at the ANNRI in the MLF of the J-PARCTakada, Shusuke*; Okudaira, Takuya*; Goto, Fumiya*; Hirota, Katsuya*; Kimura, Atsushi; Kitaguchi, Masaaki*; Koga, Jun*; Nakao, Taro*; Sakai, Kenji; Shimizu, Hirohiko*; et al.
Journal of Instrumentation (Internet), 13(2), p.P02018_1 - P02018_21, 2018/02
Times Cited Count:8 Percentile:31.10(Instruments & Instrumentation)Oe, Kazuhiro*; Attallah, M. F.*; Asai, Masato; Goto, Naoya*; Gupta, N. S.*; Haba, Hiromitsu*; Huang, M.*; Kanaya, Jumpei*; Kaneya, Yusuke*; Kasamatsu, Yoshitaka*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 303(2), p.1317 - 1320, 2015/02
Times Cited Count:11 Percentile:60.54(Chemistry, Analytical)A new technique for continuous dissolution of nuclear reaction products transported by a gas-jet system was developed for superheavy element (SHE) chemistry. In this technique, a hydrophobic membrane is utilized to separate an aqueous phase from the gas phase. With this technique, the dissolution efficiencies of short-lived radionuclides of
Mo and
W were measured. Yields of more than 80% were observed for short-lived radionuclides at aqueous-phase flow rates of 0.1-0.4 mL/s. The gas flow-rate had no influence on the dissolution efficiency within the studied flow range of 1.0-2.0 L/min. These results show that this technique is applicable for on-line chemical studies of SHEs in the liquid phase.
Kasada, Ryuta*; Goto, Takuya*; Fujioka, Shinsuke*; Hiwatari, Ryoji*; Oyama, Naoyuki; Tanigawa, Hiroyasu; Miyazawa, Junichi*; Young Scientists Special Interest Group on Fusion Reactor Realization*
Purazuma, Kaku Yugo Gakkai-Shi, 89(4), p.193 - 198, 2013/04
Japanese young researchers who have interest in realizing fusion reactor have analyzed Technology Readiness Levels (TRL) in Young Scientists Special Interest Group on Fusion Reactor Realization. In this report, brief introduction to TRL assessment and a view of TRL assessment against fusion reactor projects conducting in Japan.
Honda, Mitsunori; Goto, Takuya*; Sakanaka, Yoshihide*; Okamoto, Yoshihiro; Suzuki, Shinichi; Yaita, Tsuyoshi
no journal, ,
no abstracts in English

Honda, Mitsunori; Goto, Takuya*; Sakanaka, Yoshihide*; Hasegawa, Yuri; Suzuki, Shinichi; Yaita, Tsuyoshi
no journal, ,
no abstracts in English
Honda, Mitsunori; Goto, Takuya*; Sakanaka, Yoshihide*; Suzuki, Shinichi; Yaita, Tsuyoshi
no journal, ,
no abstracts in English
2 surfaceYamamoto, Yoshihisa*; Togashi, Hideaki*; Kato, Atsushi*; Hasegawa, Satoshi*; Goto, Seiichi*; Nakano, Takuya*; Suemitsu, Maki*; Narita, Yuzuru*; Yoshigoe, Akitaka; Teraoka, Yuden
no journal, ,
We have investigated the initial oxidation process on an Si(110)-16
2 surface by real time synchrotron radiation photoemission spectroscopy (SR-XPS). As a result, a rapid initial oxidation regime was found to exist on this surface, which is not present on other crystal orientations. Analyses of the O1s spectra suggest insertion of oxygen atoms at the Si-Si bonds as the predominant process during initial oxidation. The rapid initial oxidation is accompanied by decrease of the Si2p subpeak that is related to Si(110)-16
2 reconstruction, indicating the preferential oxidation at the pentagon pair.
2Nakano, Takuya*; Hasegawa, Satoshi*; Togashi, Hideaki*; Kato, Atsushi*; Goto, Seiichi*; Teraoka, Yuden; Yoshigoe, Akitaka; Suemitsu, Maki*
no journal, ,
no abstracts in English
2 surface and surface reconstructionTogashi, Hideaki*; Yamamoto, Yoshihisa*; Goto, Seiichi*; Takahashi, Yuya*; Nakano, Takuya*; Konno, Atsushi*; Suemitsu, Maki*; Asaoka, Hidehito; Yoshigoe, Akitaka; Teraoka, Yuden
no journal, ,
Initial oxidaion processes at Si(110)-16
2 clean surface with O
mokecules have been observed by real-time SR-XPS and STM methods. SR-XPS experiments were performed at BL23SU in SPring-8 and STM experiments were performed in JAEA Tokai research center. From comparison of oxygen uptake curves of Si(110)-16
2 with Si(001)-2
1, following conclusions were obtained. Rapid initial oxidation occured at the Si(110) surface and layer-by-layer oxidation was also took place. In-situ observation with STM revealed that the rapid initial oxidation was due to oxygen adsorption at pentagon-pair Si atoms on the topmost surface, at least 4 kinds of oxygen-adsorbed states, and the DD site was a condensed oxidation state.
Toyoshima, Atsushi; Asai, Masato; Attallah, M. F.*; Goto, Naoya*; Gupta, N. S.*; Haba, Hiromitsu*; Huang, M.*; Kanaya, Jumpei*; Kaneya, Yusuke; Kasamatsu, Yoshitaka*; et al.
no journal, ,
Towards electrolytic reduction of Sg, batch-wise electrolytic reduction of carrier-free
Mo and
W radiotracers was studied using a flow electrolytic column (FEC). The electrolyzed samples from a FEC were chemically analyzed by solvent extraction with TOA and HDEHP to separate and identify reduced species from the stable Mo(VI) and W(VI) ones based on their different extraction behavior.
Mo and
W were applied as radiotracers. We also performed cyclic voltammetry and UV/Vis absorption spectrometry of macro amounts of Mo and W in acidic solutions to obtain information on redox reactions of these elements under given conditions. In the conference, the present status of the preparatory reduction experiments with Mo and W will be presented.
Toyoshima, Atsushi; Miyashita, Sunao*; Oe, Kazuhiro*; Kitayama, Yuta*; Lerum, H. V.*; Goto, Naoya*; Kaneya, Yusuke; Komori, Yukiko*; Mitsukai, Akina*; Vascon, A.; et al.
no journal, ,
no abstracts in English
Toyoshima, Atsushi; Oe, Kazuhiro*; Asai, Masato; Attallah, M. F.*; Goto, Naoya*; Gupta, N. S.*; Haba, Hiromitsu*; Kaneko, Masashi*; Kaneya, Yusuke; Kasamatsu, Yoshitaka*; et al.
no journal, ,
Due to short half-lives less than 10 s and extremely low production rates, transactinide elements heavier than seaborgium (Sg) are produced on an atom per hour scale. Therefore, a continuous rapid chemistry assembly is required to study aqueous-phase chemistry of these heaviest elements. In the present study, we started developments of a continuous chemistry assembly. Our first attempt was made in on-line experiments with Mo and W, lighter homologs of Sg, to optimize a chemistry assembly consisting of a newly developed membrane degasser as an interface between gas-jet and aqueous phase, a flow electrolytic column apparatus utilized to control oxidation states of Mo and W ions, and the continuous liquid-liquid extraction apparatus of SISAK for separation. In the conference, present status of the developments will be presented.
2 surfaceTogashi, Hideaki*; Yamamoto, Yoshihisa*; Goto, Seiichi*; Takahashi, Yuya*; Nakano, Takuya*; Kato, Atsushi*; Hasegawa, Satoshi*; Konno, Atsushi*; Suemitsu, Maki*; Asaoka, Hidehito; et al.
no journal, ,
no abstracts in English
Honda, Mitsunori; Kaneta, Yui; Muraguchi, Masakazu*; Hayakawa, Kosetsu*; Oda, Masato*; Iino, Chiaki*; Ishii, Hiroyuki*; Goto, Takuya*; Yaita, Tsuyoshi
no journal, ,
Ten years have passed since the Great East Japan Earthquake and the accident at the Fukushima Daiichi Nuclear Power Plant, and the contaminated soil generated in Fukushima Prefecture has been decontaminated and managed as removal soil. We have been conducting research on the volume reduction and recycling of Fukushima weathered biotite, which is known to be a strong adsorbent of radioactive Cs contained in the removed soil. In this study, thermoelectric properties (Seebeck coefficient, electrical conductivity, and thermal diffusivity) of soil clay minerals and molten salt-electrolyzed soil clay minerals were evaluated in order to clarify their properties as thermoelectric materials.
Honda, Mitsunori; Kaneta, Yui; Muraguchi, Masakazu*; Hayakawa, Kosetsu*; Oda, Masato*; Iino, Chiaki*; Ishii, Hiroyuki*; Goto, Takuya*; Yaita, Tsuyoshi
no journal, ,
Ten years have passed since the earthquake and nuclear power plant accident at 1F that occurred in 2011, and the contaminated soil generated in Fukushima Prefecture is now being managed as removed soil at intermediate storage facilities. In the course of developing technology to remove cesium from the removed soil, we have focused on the functionality of crystalline minerals after removal of cesium, and have been investigating their potential as thermoelectric materials. In this study, we report on the evaluation of thermoelectric properties (electrical conductivity, thermal diffusivity, and Seebeck coefficient) and structural analysis of crystalline minerals.
Honda, Mitsunori; Kaneta, Yui; Muraguchi, Masakazu*; Hayakawa, Kosetsu*; Oda, Masato*; Iino, Chiaki*; Ishii, Hiroyuki*; Goto, Takuya*; Yaita, Tsuyoshi
no journal, ,
Twelve years have passed since the 1F accident that occurred in 2011, and contaminated soil generated in Fukushima Prefecture is being managed as removed soil. We have focused on the functionality of several crystalline minerals obtained in the process of developing a technology to remove Cs from the removed soil, and are examining their potential as thermoelectric conversion materials. In this study, we report on the evaluation of thermoelectric properties (electrical conductivity, thermal diffusivity, and Seebeck coefficient) of the crystalline minerals.
Honda, Mitsunori; Kaneta, Yui; Hayakawa, Kosetsu*; Muraguchi, Masakazu*; Iino, Chiaki*; Oda, Masato*; Ishii, Hiroyuki*; Goto, Takuya*; Yaita, Tsuyoshi
no journal, ,
In this study, thermoelectric properties (electrical conductivity, Seebeck coefficient, and thermal diffusivity) were evaluated (OZMA-1-S1) for polycrystalline minerals obtained by systematically changing the conditions of WB and the molten treatment. The Seebeck coefficient and thermal diffusivity were evaluated on the same sample. Macroscopic and microscopic structures were identified by various X-ray analyses and first-principles calculations. As for the electrical conductivity results of WB, the biotite material is usually known as an electrical insulator at room temperature, but after grinding, classification, molten salt treatment, and sintering, it was found to have electrical conductivity on the order of 1.49
10
(
V/K) in the temperature range 650-850
C, indicating that it has semiconducting electrical conductivity properties. Seebeck coefficient measurements in the same temperature range showed a high value of -2.0
10
(
V/K). Calculating the dimensionless performance index
from the obtained results,
=0.29 was obtained. Regarding the thermoelectric property evaluation results for the molten salt treated polycrystalline minerals, higher electrical conductivity properties than WB were obtained for the same temperature range. These results suggest that WB can be used to show useful thermoelectric properties in the high temperature region above 650
C.