Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Micheau, C.; Ueda, Yuki; Motokawa, Ryuhei; Akutsu, Kazuhiro*; Yamada, Norifumi*; Yamada, Masako*; Moussaoui, S. A.*; Makombe, E.*; Meyer, D.*; Berthon, L.*; et al.
Journal of Molecular Liquids, 401, p.124372_1 - 124372_12, 2024/05
Times Cited Count:0 Percentile:0.00(Chemistry, Physical)Kim, G.*; Im, S.*; Jee, H.*; Suh, H.*; Cho, S.*; Kanematsu, Manabu*; Morooka, Satoshi; Koyama, Taku*; Nishio, Yuhei*; Machida, Akihiko*; et al.
Cement and Concrete Research, 159, p.106869_1 - 106869_17, 2022/09
Times Cited Count:22 Percentile:89.36(Construction & Building Technology)Wang, Q.*; Hu, Q.*; Zhao, C.*; Yang, X.*; Zhang, T.*; Ilavsky, J.*; Kuzmenko, I.*; Ma, B.*; Tachi, Yukio
International Journal of Coal Geology, 261, p.104093_1 - 104093_15, 2022/09
Times Cited Count:10 Percentile:74.93(Energy & Fuels)Tominaga, Masahide*; Nagayasu, Yukari*; Sasaki, Motoharu*; Furuta, Takuya; Hayashi, Hiroaki*; Oita, Masataka*; Nishiyama, Yuichi*; Haga, Akihiro*
Radiological Physics and Technology, 14(4), p.381 - 389, 2021/12
Due to recent advance of diagnostic radiology, the increase of diagnostic radiation exposure to patient becomes problem. Diagnostic Reference Levels has been released to optimized the radiation exposure to patients in Japan recently. The evaluation of entrance surface dose (ESD) is recommended to assess the dose level for general X-ray examination. The ESD can be easily evaluated by multiplying the backscatter factor of the patient body on the free-in-air air kerma. The air kerma free-in-air value used to estimate ESD may contain X-rays scattered from obstacles located at the time of measurement, which may induce non-minor error in assessments. We therefore studied the influence of scattered X-rays on air kerma measurement under various environments (distances, field sizes, and materials). It was found that the dependence on the X-ray energy and field size was different for different materials. The X-ray contamination can be ignored for all the materials when the distance to the scatterer exceeds 35 cm.
Fujiwara, Satoru*; Matsuo, Tatsuhito*; Sugimoto, Yasunobu*; Shibata, Kaoru
Journal of Physical Chemistry Letters (Internet), 10(23), p.7505 - 7509, 2019/12
Times Cited Count:4 Percentile:19.36(Chemistry, Physical)Characterization of the dynamics of disordered polypeptide chains is required to elucidate the behavior of intrinsically disordered proteins and proteins under non-native states related to the folding process. Here we develop a method using quasielastic neutron scattering, combined with small-angle X-ray scattering and dynamic light scattering, to evaluate segmental motions of proteins as well as diffusion of the entire molecules and local side-chain motions. We apply this method to RNase A under the unfolded and molten-globule (MG) states. The diffusion coefficients arising from the segmental motions are evaluated and found to be different between the unfolded and MG states. The values obtained here are consistent with those obtained using the fluorescence-based techniques. These results demonstrate not only feasibility of this method but also usefulness to characterize the behavior of proteins under various disordered states.
Fujiwara, Satoru*; Kono, Fumiaki*; Matsuo, Tatsuhito*; Sugimoto, Yasunobu*; Matsumoto, Tomoharu*; Narita, Tetsuhiro*; Shibata, Kaoru
Journal of Molecular Biology, 431(17), p.3229 - 3245, 2019/08
Times Cited Count:15 Percentile:53.70(Biochemistry & Molecular Biology)-synuclein (Syn) is an intrinsically disordered protein (IDP) with unknown function. Syn is known to form amyloid fibrils, which are implicated with the pathogenesis of Parkinson's disease and other synucleinopathies. Elucidating the mechanism of fibril formation of Syn is therefore important for understanding the mechanism of the pathogenesis of these diseases. Here, using the quasielastic neutron scattering (QENS) and small-angle X-ray scattering (SAXS) techniques, we investigated the dynamic and structural properties of Syn. These results imply that fibril formation of Syn requires not only the enhanced local motions but also the segmental motions such that the proper inter-molecular interactions are possible.
Yoshida, Koji*; Inoue, Takuya*; Torigoe, Motokatsu*; Yamada, Takeshi*; Shibata, Kaoru; Yamaguchi, Toshio*
Journal of Chemical Physics, 149(12), p.124502_1 - 124502_10, 2018/09
Times Cited Count:4 Percentile:16.28(Chemistry, Physical)Differential scanning calorimetry, X-ray diffraction, and quasi-elastic neutron scattering (QENS) measurements of aqueous glycine solutions confined in mesoporous silica (MCM-41) were performed at different glycine concentrations, pH, and loading ratio (= mass of glycine solution / mass of dry MCM-41) in the temperature range from 305 to 180 K to discuss the confinement effect on the thermal behavior, the structure, and the dynamic properties of the solutions.
Tsutsui, Satoshi*; Kaneko, Koji; Pospisil, J.; Haga, Yoshinori
Physica B; Condensed Matter, 536, p.24 - 27, 2018/05
Times Cited Count:3 Percentile:14.38(Physics, Condensed Matter)Hosokawa, Shinya*; Kimura, Koji*; Yamasaki, Michiaki*; Kawamura, Yoshihito*; Yoshida, Koji*; Inui, Masanori*; Tsutsui, Satoshi*; Baron, A. Q. R.*; Kawakita, Yukinobu; Ito, Shinichi*
Journal of Alloys and Compounds, 695, p.426 - 432, 2017/02
Times Cited Count:3 Percentile:15.44(Chemistry, Physical)Oka, Hiroshi; Tanno, Takashi; Otsuka, Satoshi; Yano, Yasuhide; Uwaba, Tomoyuki; Kaito, Takeji; Onuma, Masato*
Nuclear Materials and Energy (Internet), 9, p.346 - 352, 2016/12
Times Cited Count:22 Percentile:88.36(Nuclear Science & Technology)Stellhorn, J. R.*; Hosokawa, Shinya*; Pilgrim, W.-C.*; Kawakita, Yukinobu; Kamimura, Kenji*; Kimura, Koji*; Blanc, N.*; Boudet, N.*
Zeitschrift fr Physikalische Chemie, 230(3), p.369 - 386, 2016/03
Times Cited Count:4 Percentile:8.78(Chemistry, Physical)Stellhorn, J. R.*; Hosokawa, Shinya*; Kawakita, Yukinobu; Gies, D.*; Pilgrim, W.-C.*; Hayashi, Koichi*; Oyama, Kenji*; Blanc, N.*; Boudet, N.*
Journal of Non-Crystalline Solids, 431, p.68 - 71, 2016/01
Times Cited Count:6 Percentile:28.92(Materials Science, Ceramics)Ishii, Kenji; Tsutsui, Kenji*; Endo, Yasuo*; Toyama, Takami*; Maekawa, Sadamichi*; Hoesch, M.; Kuzushita, Kaori; Inami, Toshiya; Tsubota, Masami; Yamada, Kazuyoshi*; et al.
AIP Conference Proceedings 850, p.403 - 404, 2006/09
We report a resonant inelastic X-ray scattering (RIXS) study of charge excitations in the electron-doped high- superconductor NdCeCuO. The intraband and interband excitations across the Fermi energy are separated for the first time by tuning the experimental conditions properly to measure charge excitations at low energy. A dispersion relation with -dependent width emerges clearly in the intraband excitation, while the intensity of the interband excitation is concentrated around 2 eV near the zone center. The experimental results are consistent with theoretical calculation of the RIXS spectra based on the Hubbard model.
Ishii, Kenji; Tsutsui, Kenji*; Endo, Yasuo*; Toyama, Takami*; Kuzushita, Kaori; Inami, Toshiya; Owada, Kenji; Maekawa, Sadamichi*; Masui, Takahiko*; Tajima, Setsuko*; et al.
AIP Conference Proceedings 850, p.445 - 446, 2006/09
Mott gap excitations in the optimally doped high- superconductor YBaCuO ( = 93 K) have been studied by the resonant inelastic X-ray scattering method. Anisotropic spectra in the -plane are observed in a twin-free crystal. The excitation from the one-dimensional CuO chain is enhanced at 2 eV near the zone boundary of the direction, while the excitation from the CuO plane is broad at 1.5-4 eV and almost independent of the momentum transfer. Theoretical calculation based on the one-dimensional and two-dimensional Hubbard model reproduces the observed spectra when different values of the on-site Coulomb energy are assumed. The Mott gap of the CuO chain site is found to be much smaller than that of the CuO plane site.
Ishii, Kenji; Kuzushita, Kaori; Murakami, Yoichi; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika
Journal of the Physical Society of Japan, 75(Suppl.), p.102 - 104, 2006/08
UPdAl is an attractive material because of the coexistence of the antiferromagnetic order below = 14.5 K and superconductivity below = 2 K. In order to discuss the coupling between magnetism and superconductivity by resonant magnetic X-ray scattering (RMXS), nature of the resonance at each absorption edge should be clarified before the measurements across . Therefore we performed RMXS study from U to edge at . In addition to a huge resonance at -edge, we observed a resonant feature at -edge which corresponds to the transition from to orbitals, while resonance at -edge and -edge is rather small.
Ishii, Kenji; Inami, Toshiya; Owada, Kenji; Kuzushita, Kaori; Mizuki, Junichiro; Murakami, Yoichi; Ishihara, Sumio*; Endo, Yasuo*; Maekawa, Sadamichi*; Hirota, Kazuma*; et al.
Journal of Physics and Chemistry of Solids, 66(12), p.2157 - 2162, 2005/12
Times Cited Count:0 Percentile:0.00(Chemistry, Multidisciplinary)We have studied electronic excitations of hole-doped manganese oxides LaSrMnO ( and ) by resonant inelastic X-ray scattering at Mn K absorption edge. We observed in the excitation spectra that the Mott gap of LaSrMnO was filled by hole-doping. In LaSrMnO, which shows a metal-insulator transition, we found that temperature dependence of scattering intensity is different between two scattering vectors. It may reflects a anisotropic electronic structure which originates from the orbital degrees of freedom in manganese oxides.
Ishii, Kenji; Tsutsui, Kenji*; Endo, Yasuo*; Toyama, Takami*; Kuzushita, Kaori; Inami, Toshiya; Owada, Kenji; Maekawa, Sadamichi*; Masui, Takahiko*; Tajima, Setsuko*; et al.
Physical Review Letters, 94(18), p.187002_1 - 187002_4, 2005/05
Times Cited Count:40 Percentile:80.55(Physics, Multidisciplinary)Mott gap excitations in the optimally doped high- superconductor YBaCuO ( = 93 K) have been studied by the resonant inelastic X-ray scattering method. Anisotropic spectra in the -plane are observed in a twin-free crystal. The excitation from the one-dimensional CuO chain is enhanced at 2 eV near the zone boundary of the direction, while the excitation from the CuO plane is broad at 1.5-4 eV and almost independent of the momentum transfer. Theoretical calculation based on the one-dimensional and two-dimensional Hubbard model reproduces the observed spectra when different values of the on-site Coulomb energy are assumed. The Mott gap of the CuO chain site is found to be much smaller than that of the CuO plane site.
Ishii, Kenji; Tsutsui, Kenji*; Endo, Yasuo*; Toyama, Takami*; Maekawa, Sadamichi*; Hoesch, M.; Kuzushita, Kaori; Tsubota, Masami; Inami, Toshiya; Mizuki, Junichiro; et al.
Physical Review Letters, 94(20), p.207003_1 - 207003_4, 2005/05
Times Cited Count:74 Percentile:89.30(Physics, Multidisciplinary)We report a resonant inelastic X-ray scattering (RIXS) study of charge excitations in the electron-doped high- superconductor NdCeCuO. The intraband and interband excitations across the Fermi energy are separated for the first time by tuning the experimental conditions properly to measure charge excitations at low energy. A dispersion relation with -dependent width emerges clearly in the intraband excitation, while the intensity of the interband excitation is concentrated around 2 eV near the zone center. The experimental results are consistent with theoretical calculation of the RIXS spectra based on the Hubbard model.
Owada, Kenji; Fujii, Yasuhiko; Katsuki, Yuya*; Muraoka, Jiro*; Nakao, Hironori*; Murakami, Yoichi; Sawa, Hiroshi*; Ninomiya, Emi*; Isobe, Masahiko*; Ueda, Yutaka*
Physical Review Letters, 94(10), p.106401_1 - 106401_4, 2005/03
Times Cited Count:24 Percentile:71.80(Physics, Multidisciplinary)The present resonant X-ray scattering has been performed on a monoclinically-split single domain of NaVO. The observation of a critically enhanced contrast between V and V ions has led us to the unequivocal conclusion of the charge-order pattern of low-temperature phase of NaVO below = 35 K. In spite of the possible four types of configuration of the zig-zag-type charge-order patterns in the -plane (A, A', B and B'), the stacking sequence along the -axis is determined as the AAA'A' type by comparison with model calculations. By assigning the A and A' configurations to Ising spins, one can reasonably explain the previously discovered "devil's staircase"-type behavior with respect to the modulation of layer-stacking sequences at high pressures and low temperatures, which clearly resembles the global phase diagram theoretically predicted by the ANNNI model.
Fukuda, Tatsuo; Mizuki, Junichiro; Ikeuchi, Kazuhiko*; Yamada, Kazuyoshi*; Baron, A. Q. R.*; Tsutsui, Satoshi*
Physical Review B, 71(6), p.060501_1 - 060501_4, 2005/02
Times Cited Count:58 Percentile:85.86(Materials Science, Multidisciplinary)Phonons along the [100] direction, in particular the highest energy Cu-O bond-stretching LO mode, of LaSrCuO have been studied by inelastic X-ray scattering experiments. The LO phonon mode in the = 0.12 sample shows significant softening similar to early neutron studies. We show here a recovery of the softening was found in the = 0.29 sample, where superconductivity degrades and normal metallic conductivity dominates. The results suggest one-to-one correspondence between the softening of this LO phonon and the superconductivity.