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O
with electrochemical Li
intercalationMurase, Satoshi*; Yoshikawa, Yumi*; Fujiwara, Kosuke*; Fukada, Yukimasa*; Teranishi, Takashi*; Kano, Jun*; Fujii, Tatsuo*; Inada, Yasuhiro*; Katayama, Misaki*; Yoshii, Kenji; et al.
Journal of Physics and Chemistry of Solids, 162, p.110468_1 - 110468_6, 2022/03
Times Cited Count：0 Percentile：0(Chemistry, Multidisciplinary)We report a trial of the valence control for mixed valence iron triangular oxide YbFeO in order to develop an effective technique to control the frustration of charges in strongly correlated electron systems. The electro-chemical doping of Li into YbFeO was examined on the cell type sample similar to the Li-ion secondary battery cell. Systematic change of the lattice constant, Fe-Fe and Fe-Yb distance were observed with Li doping. Maximum value of the doping was over 300 mAh/g. An EXAFS experiment indicated that Li positioned between Yb octahedron layer (U-layer) and Fe-bipyramidal layer (W-layer). However, detailed change of iron valence state of YbFeO was not clearly observed because of the superimpose of the signal from iron metal nano particles in XANES observation. The results indicate that the electrochemical method might be one of the potential technique to control the frustration of charges in YbFeO.
Kitazato, Kohei*; Milliken, R. E.*; Iwata, Takahiro*; Abe, Masanao*; Otake, Makiko*; Matsuura, Shuji*; Takagi, Yasuhiko*; Nakamura, Tomoki*; Hiroi, Takahiro*; Matsuoka, Moe*; et al.
Nature Astronomy (Internet), 5(3), p.246 - 250, 2021/03
Times Cited Count：43 Percentile：96.93(Astronomy & Astrophysics)Here we report observations of Ryugu's subsurface material by the Near-Infrared Spectrometer (NIRS3) on the Hayabusa2 spacecraft. Reflectance spectra of excavated material exhibit a hydroxyl (OH) absorption feature that is slightly stronger and peak-shifted compared with that observed for the surface, indicating that space weathering and/or radiative heating have caused subtle spectral changes in the uppermost surface. However, the strength and shape of the OH feature still suggests that the subsurface material experienced heating above 300 
C, similar to the surface. In contrast, thermophysical modeling indicates that radiative heating does not increase the temperature above 200 C at the estimated excavation depth of 1 m, even if the semimajor axis is reduced to 0.344 au. This supports the hypothesis that primary thermal alteration occurred due to radiogenic and/or impact heating on Ryugu's parent body.
Torigoe, Shuhei*; Ishimoto, Yutaro*; Aoishi, Yuhei*; Murakawa, Hiroshi*; Matsumura, Daiju; Yoshii, Kenji; Yoneda, Yasuhiro; Nishihata, Yasuo; Kodama, Katsuaki; Tomiyasu, Keisuke*; et al.
Physical Review B, 93(8), p.085109_1 - 085109_5, 2016/02
Times Cited Count：5 Percentile：25.9(Materials Science, Multidisciplinary)Oguri, Hidetomo; Hasegawa, Kazuo; Ito, Takashi; Chishiro, Etsuji; Hirano, Koichiro; Morishita, Takatoshi; Shinozaki, Shinichi; Ao, Hiroyuki; Okoshi, Kiyonori; Kondo, Yasuhiro; et al.
Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.389 - 393, 2014/10
no abstracts in English
Sasaki, Yuji; Tsubata, Yasuhiro; Kitatsuji, Yoshihiro; Sugo, Yumi; Shirasu, Noriko; Ikeda, Yasuhisa*; Kawasaki, Takeshi*; Suzuki, Tomoya*; Mimura, Hitoshi*; Usuda, Shigekazu*; et al.
JAEA-Research 2014-008, 220 Pages, 2014/06
JAEA-Research-2014-008.pdf:41.81MB
The researches on Development of mutual separation technology of minor actinides by the novel hydrophilic and lipophilic diamide compounds, entrusted to Japan Atomic Energy Agency by the Ministry of Education, Culture, Sports, Science and Technology of Japan, from 2010 to 2012 are summarized. This project was composed of three themes, those are (1) Development of total recovery of MA+Ln: basic researches for new extractant, DOODA, (2) Development of mutual separation of Am/Cm/Ln: basic researches of Ln-complex, solvent extraction, and extraction chromatography, and (3) Evaluation of separation technique: process simulation. For topic (1), we summarized the information on characteristic of DOODA extractant. For topic (2), we summarized the information on structures of Ln-complexes, solvent extraction and chromatography. For topic (3), we summarized the information on conditions of mixer-settler and evaluation of each fraction separated.
Fe
O
(R=Yb and Lu)Yoshii, Kenji; Ikeda, Naoshi*; Fukuyama, Ryota*; Nagata, Tomoko*; Kambe, Takashi*; Yoneda, Yasuhiro; Fukuda, Tatsuo; Mori, Shigeo*
Solid State Communications, 173, p.34 - 37, 2013/11
Times Cited Count：4 Percentile：20.56(Physics, Condensed Matter)We have investigated the magnetic properties of RFeO (R=Yb and Lu), which belongs to the homologous family of electronic ferroelectric RFeO. Magnetization measurements show ferrimagnetic ordering at the Neel temperature (T
) of about 270 K, which is slightly higher than that of RFeO (T about 230-250 K). Observation of spin glass and exchange bias shows a coexistence of ferromagnetic and antiferromagneticinteractions, similarly to RFeO. This situation gives rise to a complex magnetic change and a broad peak of magnetic entropy change. Some characteristics, such as refrigeration temperatures higher than in RFeO, seem to offer a possibility of this system to applications.
SrMnO (R = Gd, Tb and Dy)Yoshii, Kenji; Hiramitsu, Yusuke*; Okajima, Yuka*; Yoneda, Yasuhiro; Nishihata, Yasuo; Mizuki, Junichiro; Nakamura, Akio; Shimojo, Yutaka; Ishii, Yoshinobu*; Morii, Yukio; et al.
Materials Research Bulletin, 45(11), p.1574 - 1580, 2010/10
Times Cited Count：12 Percentile：37.22(Materials Science, Multidisciplinary)Magnetic and dielectric properties of perovskite manganites RSrMnO (R = Gd, Tb and Dy) have been investigated. DC and AC magnetic measurements showed short-range glassy magnetic ordering at Tg about 40 K. Such ordering was observed by neutron diffraction and is ascribable to the size mismatch of R
and Sr settled randomly at the same crystallographic site. Dielectric constants for each material were about 1000-10000 between about 50 K and 300 K and showed broad maximums above Tg. Dielectric dispersion showed poor coherency of the motion of polar regions, plausibly because of the size-mismatch effect; both the magnetic and dielectric properties of this system are governed by the randomness at the R/Sr site. The tan
and EXAFS data suggest that the dielectric response is rooted in a transfer of the Mn-3d electrons.
Na
Li
)TiO
Fukunaga, Masanori; Yoneda, Yasuhiro; Fukuyama, Ryota*; Saito, Hiroyuki; Ikeda, Naoshi*; Katayama, Yoshinori
Transactions of the Materials Research Society of Japan, 35(1), p.111 - 114, 2010/03
High-pressure synthesis of bismuth based perovskite (BiNaLi)TiO (BNLT) (
=0.1, 0.15, 0.2, 0.25, 0.4, 0.5) was demonstrated. Single phase BNLTs with perovskite structure were successfully synthesized for 
0.1 by the solid state reaction method. The solid phase reaction occurred in the pressure range of 6-10 GPa, and in the temperature range of 800-1200 C. Two thermal anomalies were observed in single phase perovskite BNLT (=0.1) as well as (Bi,Na)TiO. The cusp like anomaly at 210 C was assigned to a rhombohedral-tetragonal structural phase transition. The finished products of 
0.2 included three kinds of impurities, which were affected by the selection of starting materials.
Ti)0Yoneda, Yasuhiro; Saito, Hiroyuki; Yoshii, Kenji; Nishida, Takashi*; Hayakawa, Hironori*; Ikeda, Naoshi*
Key Engineering Materials, 421-422, p.30 - 33, 2010/00
Polycrystalline Bi(MgTi)O samples were prepared under high pressure. A mixed powder of Bi
O, TiO and MgO with a prescribed ratio was packed into platinum cell and was heated a cubic anvil-type apparatus at 6.5 GPa and 1000 
C. The obtained samples were characterized by powder X-ray diffraction measurements. Although some impurity peaks existed, the main peaks were perovskite peaks. The structure of Bi(MgTi)O is rhombohedral, as well as BiFeO. The D-E hysteresis loop was not saturated due to the impurities, but the possibility as ferroelectric can be expected enough.
Mn
O (0
x1)Yoshii, Kenji; Ikeda, Naoshi*; Michiuchi, Takamasa*; Yokota, Yusuke*; Okajima, Yuka; Yoneda, Yasuhiro; Matsuo, Yoji*; Horibe, Yoichi*; Mori, Shigeo*
Journal of Solid State Chemistry, 182(7), p.1611 - 1618, 2009/06
Times Cited Count：15 Percentile：51.45(Chemistry, Inorganic & Nuclear)We have investigated the magnetic and dielectric properties of YbFeMnO (0x1), which is an Fe-site-substituted system of new multiferroic oxides RFeO (R=Y, Ho-Lu). X-ray diffraction measurements show that a solid solution is formed between YbFeO (x=0) and YbFeMnO (x=1) for 0x1. The valence of the Mn ion is determined to be 
2+, consistently with the suppression of low-temperature magnetization by the Mn substitution. The magnetic transition temperature and the dielectric constant decrease monotonically with increasing x. This result plausibly confirms that the magnetic and dielectric properties in oxides isostructural with RFeO are governed by the electron transfer between Fe-site ions, unlike ordinary ferroelectrics and dielectrics, in which the ionic displacement plays a key role. The possibility for application is briefly discussed.
CaMnO (R=Eu-Lu)Yoshii, Kenji; Hiramitsu, Yusuke*; Yoneda, Yasuhiro; Okajima, Yuka; Nishihata, Yasuo; Mizuki, Junichiro; Ikeda, Naoshi*
Ferroelectrics, 379(1), p.183 - 190, 2009/05
Times Cited Count：9 Percentile：39.82(Materials Science, Multidisciplinary)The magnetic and dielectric properties of perovskite manganites RCaMnO (R=Eu-Lu) have been investigated. Their dielectric constants were about 1000 at around room temperature. Inflections or peaks of temperature dependences of the dielectric constants were observed at around the charge-ordering temperatures determined from the magnetic measurements. Analyses of tan and EXAFS spectra suggested that the dielectric properties of this system are due to a spatial arrangement and transfer of the Mn-3d electrons. The observation of a two-peak structure of tan indicates that dielectric measurement can be used to observe homogeneity or in homogeneity of sample, as mentioned in our previous paper.
OHayakawa, Hironori*; Morimoto, Masanori*; Ikeda, Naoshi*; Yoneda, Yasuhiro; Kohara, Shinji*; Yoshii, Kenji; Matsuo, Yoji*; Michiuchi, Takamasa*; Mori, Shigeo*
Transactions of the Materials Research Society of Japan, 34(1), p.51 - 54, 2009/05
We have recently reported that LuFeO becomes ferroelectric below 330 K, owing to a charge-ordering transition of Fe ions. As details of the properties of this material have not been reported so far, we have investigated its local structure in the ferromagnetic phase by means of synchrotron X-ray diffraction. The analysis of pair-distribution function showed the existence of displacement of Lu atoms; this structure is different from the average structure of this materials known thus far. This result encourages a detailed reinvestigation of crystal structure of LuFeO. We also show the results obtained from some other experimental methods, such as dielectric measurement and electron diffraction.
Nishio, Kazuhisa; Matsuoka, Toshiyuki; Mikake, Shinichiro; Tsuruta, Tadahiko; Amano, Kenji; Oyama, Takuya; Takeuchi, Ryuji; Saegusa, Hiromitsu; Hama, Katsuhiro; Yoshida, Haruo*; et al.
JAEA-Review 2009-001, 110 Pages, 2009/03
JAEA-Review-2009-001.pdf:49.84MB
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is developing a geoscientific research project named Mizunami Underground Research Laboratory (MIU) project in crystalline rock environment in order to establish scientific and technological basis for geological disposal of HLW. Geoscientific research at MIU is planned to be carried out in three phases over a period of 20 years; Surface-based Investigation Phase (Phase 1), Construction Phase (Phase 2) and Operation Phase (Phase 3). Currently, the project is under the Construction Phase. This document presents the following results of the research and development performed in 2006 fiscal year, as a part of the Construction Phase based on the MIU Master Plan updated in 2002, (1) Investigation at the MIU Construction Site, (2) Construction at the MIU Construction Site, (3) Research Collaboration.
Nishio, Kazuhisa; Matsuoka, Toshiyuki; Mikake, Shinichiro; Tsuruta, Tadahiko; Amano, Kenji; Oyama, Takuya; Takeuchi, Ryuji; Saegusa, Hiromitsu; Hama, Katsuhiro; Yoshida, Haruo*; et al.
JAEA-Review 2008-073, 99 Pages, 2009/03
JAEA-Review-2008-073-1.pdf:37.33MBJAEA-Review-2008-073-2.pdf:37.16MB
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is developing a geoscientific research project named Mizunami Underground Research Laboratory (MIU) project in crystalline rock environment in order to establish scientific and technological basis for geological disposal of HLW. Geoscientific research at MIU is planned to be carried out in three phases over a period of 20 years; Surface-based Investigation Phase (Phase 1), Construction Phase (Phase 2) and Operation Phase (Phase 3). Currently, the project is under the Construction Phase. This document presents the following results of the research and development performed in 2005 fiscal year, as a part of the Construction Phase based on the MIU Master Plan updated in 2002, (1) Investigation at the MIU Construction Site, (2) Construction at the MIU Construction Site, (3) Research Collaboration.
Ti
O
Yoneda, Yasuhiro; Yoshii, Kenji; Hayakawa, Hironori*; Ikeda, Naoshi*
Transactions of the Materials Research Society of Japan, 34(1), p.15 - 18, 2009/03
Recently, there has been considerable interest in the dielectric properties of the cubic perovskite CaCuTiO. The material has shown to have high and relatively temperature independent dielectric permittivity over a wide temperature range from 100 to 600 K. Below 100 K the permittivity drops by almost three orders of magnitude, but is not accompanied by a structural phase transition. We studied CaCuTiO hoping to find signatures of local structural distortions that may explain the observe anomalies in the dielectric properties. Experiments were carried out using synchrotron radiation at several temperatures between room temperature and 10 K. Reconsideration is necessary for interpreting a huge permittivity by the local disorder model.
Nishio, Kazuhisa; Oyama, Takuya; Mikake, Shinichiro; Mizuno, Takashi; Saegusa, Hiromitsu; Takeuchi, Ryuji; Amano, Kenji; Tsuruta, Tadahiko; Hama, Katsuhiro; Seno, Yasuhiro; et al.
JAEA-Review 2008-072, 28 Pages, 2009/02
JAEA-Review-2008-072.pdf:11.8MB
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is developing a geoscientific research project named the Mizunami Underground Research Laboratory (MIU) project in crystalline rock environment in order to establish scientific and technological basis for geological disposal of HLW. Geoscientific research at the MIU project is planned to be carried out in three phases over a period of 20 years; Surface-based Investigation Phase (Phase 1), Construction Phase (Phase 2) and Operation Phase (Phase 3). Currently, the project is under the Construction Phase. This document presents the following 2008 fiscal year plan based on the MIU Master Plan updated in 2002, (1) Investigation Plan, (2) Construction Plan, (3) Research Collaboration Plan, etc.
Harada, Masahide; Meigo, Shinichiro; Ito, Manabu; Dantsuji, Eiji; Takagiwa, Katsunori; Takada, Hiroshi; Maekawa, Fujio; Futakawa, Masatoshi; Nakamura, Mitsutaka; Miyake, Yasuhiro*; et al.
Nuclear Instruments and Methods in Physics Research A, 600(1), p.87 - 90, 2009/02
Times Cited Count：3 Percentile：28.22(Instruments & Instrumentation)In MLF of J-PARC, since weights of a building and shields are considerably heavy as 130,000 tons and 80,000 tons, respectively, large settlement of the MLF building is expected. The 3NBT line with 300 m in length is similar. To achieve a precise alignment under the large settlement, we conducted periodical survey measurements at the MLF building and 3NBT. At the completion of construction of the MLF building in December 2005, the settlement was about 40 mm. By extrapolating this result with weights to be added in the future for neutron beam line shields, we predicted that the MLF building settled in about 68mm at the completion of all neutron instrument construction. We decided that the muon target should be installed 5 mm higher than the neutron target with expecting future uneven settlement of the MLF building. The validation in the end of 2007 indicated that the measured level difference came up to the expected value.
O and R
R'FeO (R, R': rare earths)Yoshii, Kenji; Yoneda, Yasuhiro; Maeda, Daisuke*; Yokota, Yusuke*; Michiuchi, Takamasa*; Komatsu, Takuma*; Ikeda, Naoshi*; Matsuo, Yoji*; Mori, Shigeo*
Japanese Journal of Applied Physics, 47(9), p.7599 - 7602, 2008/09
Times Cited Count：8 Percentile：33.28(Physics, Applied)We have investigated the physical properties of HoFeO and RR'FeO (R, R': rare earths). Dielectric measurements showed their dielectric constants of 1000 at around room temperature, which is characteristic of the RFeO series (R: rare earths). However, the magnetic transition temperatures and the coherency in dielectric response were found to be different from those of RFeO reported so far. Interestingly, these materials suggested higher ferroelectric temperatures than those reported so far, suggesting a possibility of application of these materials.
O, InFeCuO, and InGaCuOYoshii, Kenji; Ikeda, Naoshi*; Okajima, Yuka; Yoneda, Yasuhiro; Matsuo, Yoji*; Horibe, Yoichi*; Mori, Shigeo*
Inorganic Chemistry, 47(14), p.6493 - 6501, 2008/07
Times Cited Count：28 Percentile：73.55(Chemistry, Inorganic & Nuclear)The magnetic and dielectric properties of InFeO, InFeCuOand InGaCuO have been investigated. All these materials areisostructural with RFeO (R=Y, Ho-Lu), which shows ferroelectricity due to iron-valence ordering. InFeO exhibits similar properties to those of RFeO; the origins of the magnetic and dielectric phenomena are likely common in InFeO and RFeO. From measurements of the other two materials, we found that both the magnetic transition temperature and the dielectric constant are decreased in the order of InFeO, InFeCuO and InGaCuO. This result strongly supports the previously reported explanation based on an electron transfer between the Fe-site ions for the corresponding rare-earth systems. Therefore, we propose that the dielectric properties of the oxides isostructural with RFeO are plausibly governed by electron transfer; this situation is different from that of ordinary ferroelectrics and dielectrics, in which the displacement factions and anions is important. In addition, InFeCuO and InGaCuO exhibit large dielectric constants (larger than about 1500). Inconsideration of this property, the possible applications of these oxides are discussed.
CaMnOHiramitsu, Yusuke*; Yoshii, Kenji; Yoneda, Yasuhiro; Mizuki, Junichiro; Nakamura, Akio; Shimojo, Yutaka; Ishii, Yoshinobu*; Morii, Yukio; Ikeda, Naoshi*
Japanese Journal of Applied Physics, Part 1, 46(10B), p.7171 - 7174, 2007/10
Times Cited Count：16 Percentile：51.23(Physics, Applied)Magnetic and dielectric properties of a perivskite manganite TbCaMnO were investigated. Magnetic measurements showed three characteristic temperatures, originating from charge ordering (300 K), antiferromagnetic ordering (120 K) and a transition to a glassy state (50 K). The coexistence of the charge and antiferromagnetic ordering was consistent with the result of powder neutron diffraction. AC dielectric measurements showed large dielectric constants of about 5000 at around room temperature. A temperature dependence of the dielectric constant changed just below the charge-ordering temperature. From the analysis of tan;, the activation energy for a domain-boundary motion was calculated to be about 0.09 eV. These results strongly suggest that the dielectric properties of this material are governed by the ordering and transfer of the Mn-3d charges.
