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Tsuji, Takuya; Matsumura, Daiju; Kobayashi, Toru
SPring-8/SACLA Riyo Kenkyu Seikashu (Internet), 12(5), p.259 - 262, 2024/10
no abstracts in English
, AgNbO, and KNbOYoneda, Yasuhiro; Kobayashi, Toru; Tsuji, Takuya; Matsumura, Daiju; Saito, Yuji; Noguchi, Yuji*
Japanese Journal of Applied Physics, 63(9), p.09SP12_1 - 09SP12_10, 2024/09
Times Cited Count：3 Percentile：33.64(Physics, Applied)NaNbO, AgNbO, and KNbO with ABO-type perovskite system is known to possess good ferroelectric properties. We directly determined the rattling space of each atom through local structure analysis. This analysis revealed the bonding sites with large fluctuations varied with varying ion size. Experimental evidence including soft X-ray absorption spectroscopy, indicates that the A-site ions are hybridized with oxygen.
NaTiO
BaTiO solid solutionsYoneda, Yasuhiro; Kobayashi, Toru; Tsuji, Takuya; Matsumura, Daiju; Saito, Yuji; Noguchi, Yuji*
Japanese Journal of Applied Physics, 62(SM), p.SM1006_1 - SM1006_8, 2023/11
Times Cited Count：6 Percentile：44.00(Physics, Applied)BiNaTiOBaTiO (BNT
BT) solid solutions have been extensively studied because they exhibit good piezoelectric properties. In addition, a wide variety of phases are observed depending on the BT composition. Soft X-ray absorption spectroscopy and high-energy X-ray diffraction experiments of BNTBT solid solutions were performed using synchrotron radiation. From the electronic structure and local structure of BNTBT solid solution, the substitution effect of BT occurred mainly at the A site, which is the substitution site of Ba. The rhombohedral strain of the TiO
octahedron did not change with the change in BT composition, suggesting that the change in the electronic structure at the O-
absorption edge is due to the change in the hybridization state.
-edge XAFS measurementTsuji, Takuya; Matsumura, Daiju; Kobayashi, Toru
SPring-8/SACLA Riyo Kenkyu Seikashu (Internet), 11(4), p.214 - 217, 2023/08
no abstracts in English
Ouchi, Kazuki; Matsumura, Daiju; Tsuji, Takuya; Kobayashi, Toru; Otobe, Haruyoshi; Kitatsuji, Yoshihiro
RSC Advances (Internet), 13(24), p.16321 - 16326, 2023/05
Times Cited Count：4 Percentile：18.03(Chemistry, Multidisciplinary)We clarified the chemical state transformation of deposits following the reduction of uranyl ion (U
O
) from the results of electrochemical quartz crystal microbalance, impedance spectra and X-ray absorption fine structure measurements. We propose the following deposition mechanism: (1) U
is formed by the disproportionation of U
. (2) U forms U hydroxide deposits, and (3) finally, the hydroxide deposits transform into U oxide, generally having a larger electrical resistance than the former.
Tsuji, Takuya; Matsumura, Daiju; Kobayashi, Toru; Yaita, Tsuyoshi
SPring-8/SACLA Riyo Kenkyu Seikashu (Internet), 11(1), p.15 - 18, 2023/02
no abstracts in English
O
Yoshioka, Satoru*; Tsuruta, Konosuke*; Yamamoto, Tomokazu*; Yasuda, Kazuhiro*; Matsumura, Sho*; Sugiyama, Takeharu*; Oba, Yojiro; Ishikawa, Norito; Kobayashi, Eiichi*; Okudaira, Koji*
Journal of the American Ceramic Society, 103(8), p.4654 - 4663, 2020/08
Times Cited Count：8 Percentile：28.80(Materials Science, Ceramics)X-ray absorption near edge structure (XANES) and small-angle X-ray scattering (SAXS) reveal the damaged structures in MgAlO spinel induced by swift heavy ions. SAXS indicates the formation of ion tracks with cylindrical shape with a diameter of 5 nm. XANES indicates the cationic disordering between tetrahedral and octahedral sites by the irradiation. Quantitative analysis of XANES also reveals that cations preferably occupy the octahedral sites at high fluence.
Sugiura, Yuki; Tomura, Tsutomu*; Ishidera, Takamitsu; Doi, Reisuke; Francisco, P. C. M.; Shiwaku, Hideaki; Kobayashi, Toru; Matsumura, Daiju; Takahashi, Yoshio*; Tachi, Yukio
Journal of Radioanalytical and Nuclear Chemistry, 324(2), p.615 - 622, 2020/05
Times Cited Count：8 Percentile：48.12(Chemistry, Analytical)
-trimethylglycineSuzuki, Tomoya*; Narita, Hirokazu*; Ogata, Takeshi*; Suzuki, Hideya; Matsumura, Tatsuro; Kobayashi, Toru; Shiwaku, Hideaki; Yaita, Tsuyoshi
Solvent Extraction Research and Development, Japan, 26(1), p.11 - 19, 2019/06
Times Cited Count：3 Percentile：10.03(Chemistry, Multidisciplinary)The ability of AMP03, a styrene-divinylbenzene copolymer functionalized with -trimethylglycine moieties, to adsorb Pd(II) from HNO
solutions was investigated to elucidate the affinity of -trimethylglycine for Pd(II). In the present study, we investigated the mechanism of Pd(II) adsorption by AMP03 by means of adsorption experiments, Fourier Transform Infrared (FT-IR) spectroscopy, and Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy.
Kato, Masaru*; Muto, Marika*; Matsubara, Naohiro*; Uemura, Yohei*; Wakisaka, Yuki*; Yoneuchi, Tsubasa*; Matsumura, Daiju; Ishibara, Tomoko*; Tokushima, Takashi*; Noro, Shinichiro*; et al.
ACS Applied Energy Materials (Internet), 1(5), p.2358 - 2364, 2018/05
Times Cited Count：18 Percentile：47.50(Chemistry, Physical)O induced by swift heavy ionsYoshioka, Satoru*; Tsuruta, Konosuke*; Yamamoto, Tomokazu*; Yasuda, Kazuhiro*; Matsumura, Sho*; Ishikawa, Norito; Kobayashi, Eiichi*
Physical Chemistry Chemical Physics, 20(7), p.4962 - 4969, 2018/02
Times Cited Count：11 Percentile：40.56(Chemistry, Physical)Cationic disorder in the MgAlO spinel induced by swift heavy ions was investigated using the X-ray absorption near edge structure. With changes in the irradiation fluences of 200 MeV Xe ions, the Mg K-edge and Al K-edge spectra were synchronously changed. The calculated spectra based on density function theory indicate that the change in the experimental spectra was due to cationic disorder between Mg in tetrahedral sites and Al in octahedral sites. These results suggest a high inversion degree to an extent that the completely random configuration is achieved in MgAlO induced by the high density electronic excitation under swift heavy ion irradiation.
Yoshigoe, Akitaka; Shiwaku, Hideaki; Kobayashi, Toru; Shimoyama, Iwao; Matsumura, Daiju; Tsuji, Takuya; Nishihata, Yasuo; Kogure, Toshihiro*; Okochi, Takuo*; Yasui, Akira*; et al.
Applied Physics Letters, 112(2), p.021603_1 - 021603_5, 2018/01
Times Cited Count：8 Percentile：30.98(Physics, Applied)A synchrotron radiation photoemission electron microscope (SR-PEEM) was applied to demonstrate pinpoint analysis of micrometer-sized weathered biotite clay particles with artificially adsorbed cesium (Cs) atoms. Despite the insulating properties of the clay, we observed the spatial distributions of constituent elements (Si, Al, Cs, Mg, Fe) without charging issues. We found that Cs atoms were likely to be adsorbed evenly over the entire particle. Spatially-resolved X-ray absorption spectra (XAS) of the Cs M
-edge region showed Cs to be present in a monocation state (Cs
). Further pinpoint XAS measurements were also performed at the Fe L
-edge to determine the chemical valence of the Fe atoms. Our results demonstrate the utility of SR-PEEM as a tool for spatially-resolved chemical analyses of various environmental substances, which is not limited by the poor conductivity of samples.
Matsumura, Daiju; Kobayashi, Toru; Miyazaki, Yuji; Okajima, Yuka*; Nishihata, Yasuo; Yaita, Tsuyoshi
Clay Science, 18(4), p.99 - 105, 2014/12
Tsuji, Takuya; Matsumura, Daiju; Kobayashi, Toru; Suzuki, Shinichi; Yoshii, Kenji; Nishihata, Yasuo; Yaita, Tsuyoshi
Clay Science, 18(4), p.93 - 97, 2014/12
Yaita, Tsuyoshi; Kobayashi, Toru; Ikeda, Takashi; Matsumura, Daiju; Machida, Masahiko; Okumura, Masahiko; Nakamura, Hiroki
Hoshako, 27(6), p.315 - 322, 2014/11
no abstracts in English
La
B studied by resonant X-ray diffractionMatsumura, Takeshi*; Michimura, Shinji*; Inami, Toshiya; Otsubo, Toru*; Tanida, Hiroshi*; Iga, Fumitoshi*; Sera, Masafumi*
JPS Conference Proceedings (Internet), 3, p.014008_1 - 014008_6, 2014/06
We study the 
-type antiferro-octupole (AFO) ordered state of CeLaB below 1.5 K by resonant X-ray diffraction in magnetic fields. Multipole moments induced by the field in the AFO phase are identified. In a mean-field model for the AFO order within the 
quartet crystal-field ground state, the 
and 
antiferroquadrupoles (AFQ) are expected as mostly induced AFQ. However, in contrast to this expectation, the main induced moment is found to be the 
-type AFQ.
LaB from resonant X-ray diffraction in magnetic fieldsMatsumura, Takeshi*; Michimura, Shinji*; Inami, Toshiya; Otsubo, Toru*; Tanida, Hiroshi*; Iga, Fumitoshi*; Sera, Masafumi*
Physical Review B, 89(1), p.014422_1 - 014422_13, 2014/01
Times Cited Count：14 Percentile：48.15(Materials Science, Multidisciplinary)The multipole ordered phase in CeLaB (phase IV) has been studied by resonant X-ray diffraction in magnetic fields. By utilizing diamond X-ray phase plates to rotate the incident linear polarization and a conventional crystal analyzer system, full linear polarization analysis has been performed to identify the order parameters. The analysis shows that the 
quadrupoles are more induced by the field than the 
quadrupoles in phase IV, in disagreement with mean-field calculations, in which the quadrupole is the main induced moment. Hence, we consider that large fluctuations of the quadrupole is hidden behind the primary ordering of the octupole.
resolutionShimizu, Noriko*; Sugiyama, Shigeru*; Maruyama, Mihoko*; Takahashi, Yoshinori*; Adachi, Motoyasu; Tamada, Taro; Hidaka, Koshi*; Hayashi, Yoshio*; Kimura, Toru*; Kiso, Yoshiaki*; et al.
Crystal Growth & Design, 10(7), p.2990 - 2994, 2010/06
Times Cited Count：11 Percentile：70.66(Chemistry, Multidisciplinary)We report crystal growth of human immunodeficiency virus 1 protease (HIV PR) in a complex with its inhibitor KNI-272 by six different methods. Comparative analysis indicates that top-seeded solution growth (TSSG) and TSSG combined with the floating and stirring technique (TSSG-FAST) are efficient strategies for rapidly obtaining large single crystals and effectively preventing polycrystallization of the seed crystal. Neutron diffraction analysis confirmed that the crystalobtained by TSSG is a high-quality single crystal. Furthermore, crystal shape was observed to be influenced by solution flow, suggesting that the degree of supersaturation significantly affects the crystal growth direction of HIV PR complex. This finding implies that the shape of the HIV PR complex crystal might be controlled by the solution flow rate.
Adachi, Motoyasu; Ohara, Takashi; Kurihara, Kazuo; Tamada, Taro; Honjo, Eijiro; Okazaki, Nobuo; Arai, Shigeki; Shoyama, Yoshinari; Kimura, Kaname*; Matsumura, Hiroyoshi*; et al.
Proceedings of the National Academy of Sciences of the United States of America, 106(12), p.4641 - 4646, 2009/03
Times Cited Count：115 Percentile：89.84(Multidisciplinary Sciences)To further understand the catalytic mechanism and inhibitor recognition of HIV-1 protease, we need to determine the locations of key hydrogen atoms in the catalytic aspartates Asp25 and Asp125. The structure of HIV-1 protease in complex with transition-state analog KNI-272 was determined by combined neutron crystallography at 1.9 resolution and X-ray crystallography at 1.4 resolution. The resulting structural data shows that the catalytic residue Asp25 is protonated and that Asp125 is deprotonated. The proton on Asp25 makes a hydrogen bond with the carbonyl group of the allophenylnorstatine group in KNI-272. The deprotonated Asp125 bonds to the hydroxyl proton of Apns. The results provide direct experimental evidence for proposed aspects of the catalytic mechanism of HIV-1 protease; and can therefore contribute substantially to the development of specific inhibitors for therapeutic application.
Matsumura, Hiroyoshi*; Adachi, Motoyasu; Sugiyama, Shigeru*; Okada, Shino*; Yamakami, Megumi*; Tamada, Taro; Hidaka, Koshi*; Hayashi, Yoshio*; Kimura, Toru*; Kiso, Yoshiaki*; et al.
Acta Crystallographica Section F, 64(11), p.1003 - 1006, 2008/11
Times Cited Count：17 Percentile：76.71(Biochemical Research Methods)This paper reports the crystallization and preliminary neutron diffraction measurements of HIV-1 protease, a potential target for anti-HIV therapy, complexed with an inhibitor (KNI-272). The aim of this neutron diffraction study is to obtain structural information about the H atoms and to determine the protonation states of the residues within the active site. The crystal was grown to a size of 1.4 mm
by repeated macroseeding and a slow-cooling method using a two-liquid system. Neutron diffraction data were collected at room temperature using a BIX-4 diffractometer at the JRR-3 research reactor of the Japan Atomic Energy Agency (JAEA). The data set was integrated and scaled to 2.3 resolution in space group P2(1)2(1)2, with unit-cell parameters a = 59.5, b = 87.4, c = 46.8 .
