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Suzuki, Seiya; Nemoto, Yoshihiro*; Shiiki, Natsumi*; Nakayama, Yoshiko*; Takeguchi, Masaki*
Annalen der Physik, 535(9), p.2300122_1 - 2300122_12, 2023/09
Times Cited Count:0 Percentile:0.00(Physics, Multidisciplinary)Haga, Yoshinori; Opletal, P.; Tokiwa, Yoshifumi; Yamamoto, Etsuji; Tokunaga, Yo; Kambe, Shinsaku; Sakai, Hironori
Journal of Physics; Condensed Matter, 34(17), p.175601_1 - 175601_7, 2022/04
Times Cited Count:22 Percentile:85.94(Physics, Condensed Matter)Kawaguchi, Munemichi; Uno, Masayoshi*
Journal of the Ceramic Society of Japan, 128(10), p.832 - 838, 2020/10
Times Cited Count:3 Percentile:13.66(Materials Science, Ceramics)This study developed phase-field method (PFM) technique in oxide melt system by using a new mobility coefficient (). The crystal growth rates () obtained by the PFM calculation with the constant were comparable to the thermodynamic driving force in normal growth model. The temperature dependence of the was determined from the experimental crystal growth rates and the . Using the determined , the crystal growth rates () in alkali disilicate glasses, LiO-2SiO, NaO-2SiO and KO-2SiO were simulated. The temperature dependence of the was qualitatively and quantitatively so similar that the PFM calculation results demonstrated the validity of the . Especially, the obtained by the PFM calculation appeared the rapid increase just below the thermodynamic melting point () and the steep peak at around -100 K. Additionally, as the temperature decreased, the apparently approached zero ms, which is limited by the representing the interface jump process. Furthermore, we implemented the PFM calculation for the variation of the parameter in the . As the increased from zero to two, the peak of the became steeper and the peak temperature of the shifted to the high temperature side. The parameters and in the increased exponentially and decreased linearly as the atomic number of the alkali metal increased due to the ionic potential, respectively. This calculation revealed that the and in the were close and reasonable for each other.
Fukazawa, Hiroshi; Hoshikawa, Akinori; Yamauchi, Hiroki; Yamaguchi, Yasuo*; Igawa, Naoki; Ishii, Yoshinobu
Physica B; Condensed Matter, 385-386(1), p.113 - 115, 2006/11
Times Cited Count:3 Percentile:17.27(Physics, Condensed Matter)We measured neutron diffraction of powdered samples of ice containing impurities (e.g., potassium deuteroxide, sodium deuteroxide) to analyze the formation of ice XI, a deuterium-ordered phase of ice, from ice Ih, a disordered phase. We found that the diffraction profiles changed with time for several days at 62-70 K, which are below the transition temperature = 76 K. From the Rietveld analysis of the diffraction profiles, we determined the change of the structural parameters with the phase transition. The structural analysis provides direct evidence for the existence of deuteron-ordered arrangements in ice containing impurities below . On the basis of the Rietveld analysis, we obtained the mass fraction () of ice XI as functions of time and temperature. We report a structural observation for the nucleation and growth of ice XI under various conditions (such as temperature variations and impurity effects), which leads to understand whether or not f reaches unity at an infinite annealing time.
Matsuda, Tatsuma; Haga, Yoshinori; Sakai, Hironori; Ikeda, Shugo; Onuki, Yoshichika
Journal of the Physical Society of Japan, 75(Suppl.), p.85 - 87, 2006/08
Recently quasi-two-dimensional electron state in rare earth and actinide compounds with HoCoGa-type tetragonal crystal structure was attracted a lot attention in relation to heavy fermion superconductivity observed in CeCoIn, CeIrIn and PuCoGa. In order to elucidate the role of electron in these compounds, it is necessary to compare their electronic state with that of lanthanum and thorium compounds which do not possess the -electrons. The number of valence electrons in the thorium compound is the same as that of the corresponding 4-itinerant cerium compound. We have recently tried to make thorium 115 compounds by indium flux method and have succeeded in discovering the new material of ThRhIn. Crystal structure and quality were confirmed by X-ray diffraction, fluorescent X-ray analysis and EPMA. The lattice parameters were determined to be 4.681(6) and , respectively. The positional parameter of In(4) site was also determined to be .
Matsuda, Tatsuma; Haga, Yoshinori; Shishido, Hiroaki*; Ikeda, Shugo; Harima, Hisatomo*; Settai, Rikio*; Onuki, Yoshichika
Physica B; Condensed Matter, 378-380, p.1021 - 1022, 2006/05
Times Cited Count:0 Percentile:0.00(Physics, Condensed Matter)We have succeeded in growing a high-quality single crystal of ThIn with the cubic structure by the In-flux method and measured the de Haas-van Alphen (dHvA) effect. Several dHvA branches were observed, ranging from 9.0 10 to 9.37 10 Oe. The experimental results are compared to the dHvA results of CeIn under pressure of 2.7 GPa, together with the results of energy band calculations.
Sugiyama, Akira; Katsurayama, Masamichi*; Anzai, Yutaka*; Tsuboi, Taiju*
Journal of Alloys and Compounds, 408-412, p.780 - 783, 2006/02
Times Cited Count:24 Percentile:74.48(Chemistry, Physical)Laser crystals of LiYF (YLF) doped with 5 - 64 at.% of trivalent ytterbium ions (Yb) were grown by a vertical Bridgman method. As crystal growth materials of YbF and YF including YOF impurities caused opaque crystal, the YOF reduction procedure using PbF was essential before starting the crystal growth. We derived seven energy levels from the F and F manifolds of Yb: YLF by the crystal-field analysis from which we explain the observed polarized absorption and emission spectra. The intrinsic broad and complicated spectra of Yb: YLF are attributed to the strong coupling of the 4f electrons with lattice vibration of the crystal.
Matsuda, Tatsuma; Haga, Yoshinori; Ikeda, Shugo; Galatanu, A.; Yamamoto, Etsuji; Shishido, Hiroaki*; Yamada, Mineko*; Yamaura, Junichi*; Hedo, Masato*; Uwatoko, Yoshiya*; et al.
Journal of the Physical Society of Japan, 74(5), p.1552 - 1556, 2005/05
Times Cited Count:26 Percentile:73.24(Physics, Multidisciplinary)We have succeeded in growing a high-quality single crystal of UCuSi with the tetragonal structure by the Sn-flux method and measured the electrical resistivity, magnetic susceptibility, magnetization and specific heat. UCuSi is found to order antiferromagnetically below = 106 K, and follows a successive ferromagnetic ordering at = 100 K. The magnetic properties are highly anisotropic, reflecting the crystal structure. An easy-axis of magnetization is found to be the [001] direction (-axis) both in the antiferromagnetic and ferromagnetic phases, while the [100] direction (-axis) corresponds to the hard-axis in magnetization. The magnetization curve in the antiferromagnetic phase indicates a clear metamagnetic transition at a low field of about 1 kOe and changes smoothly into a ferromagnetic magnetization curve below = 100 K. The saturation moment is determined as 1.75/U at 2 K. The electronic specific heat coefficient is also determined as 20 mJ/Kmol.
Matsuda, Tatsuma; Galatanu, A.; Haga, Yoshinori; Ikeda, Shugo; Yamamoto, Etsuji; Hedo, Masato*; Uwatoko, Yoshiya*; Takeuchi, Tetsuya*; Sugiyama, Kiyohiro*; Kindo, Koichi*; et al.
Journal of the Physical Society of Japan, 73(9), p.2533 - 2538, 2004/09
Times Cited Count:8 Percentile:47.90(Physics, Multidisciplinary)Electrical resistivity, specific heat, magnetic susceptibility and high-field magnetization measurements have been performed on the ferromagnet UFeP with the cubic crystal structure. The ferromagnetic ordering at ,=,3.1 K, a small saturation moment of 1.3 /U, together with the temperature dependence of the magnetic susceptibility, are found to be well explained by considering the 5 crystalline electric field schemes for site symmetry and the magnetic exchange interaction.
Huang, X.*; Mashimo, Tsutomu; Ono, Masao; Tomita, Takeshi; Sawai, Tomotsugu; Osakabe, Toyotaka; Mori, Nobuo*
Journal of Applied Physics, 96(3), p.1336 - 1340, 2004/08
Times Cited Count:13 Percentile:46.85(Physics, Applied)Mega-gravity field experiments were performed on the BiSb(atomic percent) alloy and pure Bi below their melting points, to investigate the change in crystalline state. For the alloy centrifuged at 191-205 C, no change in composition was observed, and the grain sizes of the crystals decreased from several mm to tens of m, while no distinct change in grain size was observed for the centrifuged pure Bi. The alloy centrifuged at 220-240 C consisted of two regions with different morphologies-fine-grained crystals with grain sizes around tens of m in the low gravity region, and large crystals with grain sizes several mm long and hundreds of m wide along the direction of gravity in the high gravity region, where sedimentation of atoms was confirmed. The large crystals with hexagonal structures were formed by preferential crystal growth roughly along the c axes, and a large strain that increased as the gravitational field increased existed inside these crystals. Formation of this anomalous crystal state might be correlated with the sedimentation of atoms.
Arai, Shigeki; Chatake, Toshiyuki; Suzuki, Nobuhiro*; Mizuno, Hiroshi*; Niimura, Nobuo
Acta Crystallographica Section D, 60(6), p.1032 - 1039, 2004/06
Times Cited Count:17 Percentile:75.70(Biochemical Research Methods)The parameters used for evaluating biomacromolecular crystal quality (, /(), maximum resolution and mosaicity) strongly depend on the diffraction experimental conditions. In this paper we describe the distinctive features of the relative Wilson plot method, and we show that the overall B-factor obtained from this plot is given as a more appropriate to characterize protein crystals. The relative Wilson plot has been applied to the characterization of crystals of a B-DNA decamer d(CCATTAATGG), and crystals of the proteins DsrD (dissimilatory sulfite reductase D) and hen egg-white lysozyme (HEWL) which we have studied by neutron diffraction. We have found that the crystal qualities of the B-DNA decamer and DsrD significantly depend on the regions of the crystallization phase diagram from which samples were taken. However, in the case of HEWL, crystal quality appears to be independent on the region of the crystallization phase diagram.
Teraoka, Yuden
Nano Tekunoroji Daijiten, p.340 - 351, 2003/12
The current status of microprocesses using synchrotron radiation in Japan was reviewed. The SR-excited process is followed by SR-excited surface modification, SR-excited crystal growth and SR-excited etching. The SR-excited surface modification is followed by SR-gas-excited surface modification and SR-direct-excited surface modification. The SR-excited crystal growth is followed by SR-excited atomic layer epitaxy and SR-excited chemical vapor deposition. THe SR-excited etching is followed by SR-direct-excited etching, SR-gas-excited etching and SR ablation.
Matsuda, Tatsuma; Haga, Yoshinori; Tokiwa, Yoshifumi; Andrei, G.; Yamamoto, Etsuji; Okubo, Tomoyuki*; Onuki, Yoshichika
Acta Physica Polonica B, 34(2), p.1071 - 1074, 2003/02
We have successfully grown a single crystal of uranium intermetallic compound URhGe. The temperature dependence of electrical resistivity shows highly anisotropic behavior. Two anomalies, which correspond to the magnetic ordering temperatures, were observed in the resistivity, magnetic susceptibility and specific heat measurements at = 30 K and =25 K. The magnetic susceptibility also shows a large uniaxial anisotropy with a magnetic easy-axis along the [010] direction.
Shinohara, Ryuji*; Yamaki, Tetsuya; Yamamoto, Shunya; Ito, Hisayoshi; Asai, Keisuke*
Journal of Materials Science Letters, 21(12), p.967 - 969, 2002/06
Times Cited Count:10 Percentile:39.06(Materials Science, Multidisciplinary)no abstracts in English
Dai, Z.*; Naramoto, Hiroshi; Narumi, Kazumasa; Yamamoto, Shunya; Miyashita, Atsumi
Thin Solid Films, 360(1), p.28 - 33, 2000/02
Times Cited Count:2 Percentile:15.24(Materials Science, Multidisciplinary)no abstracts in English
Dai, Z.*; Naramoto, Hiroshi; Narumi, Kazumasa; Yamamoto, Shunya; Miyashita, Atsumi
Applied Physics Letters, 74(12), p.1686 - 1688, 1999/03
Times Cited Count:5 Percentile:28.25(Physics, Applied)no abstracts in English
Dai, Z.*; Miyashita, Atsumi; Yamamoto, Shunya; Narumi, Kazumasa; Naramoto, Hiroshi
Thin Solid Films, 349(1-2), p.51 - 55, 1999/00
Times Cited Count:4 Percentile:28.08(Materials Science, Multidisciplinary)no abstracts in English
Asaoka, Hidehito; ; Noda, Kenji
Japanese Journal of Applied Physics, 33(7A), p.L923 - L926, 1994/07
Times Cited Count:5 Percentile:34.94(Physics, Applied)no abstracts in English
Asaoka, Hidehito; ; ; ; ;
Japanese Journal of Applied Physics, 32(3A), p.1091 - 1096, 1993/03
Times Cited Count:54 Percentile:90.13(Physics, Applied)no abstracts in English
Asaoka, Hidehito; Noda, Kenji;
Nihon Kessho Seicho Gakkai-Shi, 20(2), 92 Pages, 1993/00
no abstracts in English