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Kawaguchi, Munemichi; Uno, Masayoshi*
Journal of Crystal Growth, 585, p.126590_1 - 126590_7, 2022/05
Phase-field mobility, , and crystal growth rates in crystallization of 11 oxides or mixed oxides in undercooled silicates, SiO
and GeO
liquids were calculated with a simple phase-field model (PFM), and material dependence of the
was discussed. Ratios between experimental crystal growth rates and the PFM simulation with
were confirmed to be proportional to a power of
on the solid/liquid interface process during the crystal growth in a log-log plot. We determined that parameters,
and
, of the
were
to
m
J
s
and
to
, which were unique for the materials. It was confirmed that our PFM simulation with the determined
reproduced quantitively the experimental crystal growth rates. The
has a proportional relationship with the diffusion coefficient of a cation molar mass average per unit an oxygen molar mass at
in a log-log graph. The
depends on the sum of the cation molar mass per the oxygen molar mass,
, in a compound. In
, the
decreases with the cation molar mass increasing. The assumed cause is that the B represents the degree of the temperature dependence of the
. Since the cation molar mass is proportional to an inertial resistance of the cation transfer, the
decreases with inverse of the cation molar mass. In crystallization of the silicates of heavy cation in
, the
saturates at approximately 0.67, which leads to
.
Yuguchi, Takashi*; Yamazaki, Hayato*; Ishibashi, Kozue*; Sakata, Shuhei*; Yokoyama, Tatsunori; Suzuki, Satoshi*; Ogita, Yasuhiro; Sando, Kazusa*; Imura, Takumi*; Ono, Takeshi*
Journal of Asian Earth Sciences, 226, p.105075_1 - 105075_9, 2022/04
Times Cited Count:8 Percentile:58.79(Geosciences, Multidisciplinary)Simultaneous determination of the U-Pb age of zircon and concentration of titanium in a single analysis spot, using inductively coupled plasma mass spectrometry with laser ablation sample introduction, produces paired age and temperature data of zircon crystallisation, potentially revealing time-temperature () histories for evolved magma. The Kurobegawa granite, central Japan, contains abundant mafic magmatic enclaves (MMEs). We applied this method to evaluate MMEs and their host (enclosing) granites. Cooling behaviour common to both MMEs and host rocks was found between 1.5 and 0.5 Ma. Rapid cooling from the zircon crystallisation temperature to the closure temperature of biotite K-Ar system was within
1 million year. Combining the obtained
paths of MMEs and host rocks with petrological information can provide insights into magma chamber processes. This suggests that MME flotation, migration, and spread through the magma chamber ceased at 1.5-0.5 Ma, indicating the emplacement age of the Kurobegawa granitic pluton, as no large-scale reheating episodes have occurred since then.
Kawaguchi, Munemichi; Uno, Masayoshi*
Journal of the Ceramic Society of Japan, 128(10), p.832 - 838, 2020/10
Times Cited Count:3 Percentile:12.68(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, Li
O-2SiO
, Na
O-2SiO
and K
O-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.
Aghamiri, S. M. S.*; Sowa, Takashi*; Ukai, Shigeharu*; Ono, Naoko*; Sakamoto, Kan*; Yamashita, Shinichiro
Materials Science & Engineering A, 771, p.138636_1 - 138636_12, 2020/01
Times Cited Count:39 Percentile:88.77(Nanoscience & Nanotechnology)Oxide dispersion strengthened (ODS) FeCrAl ferritic steels are being developed as potential accident tolerance fuel cladding materials for the light water reactors (LWRs) due to significant improvement in steam oxidation by alumina forming scale and good mechanical properties up to high temperatures. In this study, the microstructural characteristics and tensile properties of the two FeCrAl ODS cladding tubes with different extrusion temperatures of 1100C and 1150
C were investigated during processing conditions. While the hot extruded sample showed micron sized elongated grains with strong
-fiber in
110
texture, cold pilger rolling process change the microstructure to submicron/micron size grain structure along with texture evolution to both
-fiber (
110
texture) and
-fiber ({111} texture) via crystalline rotations. Subsequently, final annealing resulted in evolution of microstructure to large grain recrystallized structure starting at recrystallization temperature of
810-850
C. Two distinct texture development happened in recrystallized cladding tubes, i.e., only large elongated grains of (110)
211
texture following extrusion temperature of 1100
C; and two texture components of (110)
211
and {111}
112
following higher extrusion temperature of 1150
C. The different texture development and retarding of recrystallization progress in 1100
C-extruded cladding tubes were attributed to higher distribution of oxide particles.
Takeuchi, Masayuki; Yano, Kimihiko; Shibata, Atsuhiro; Sambommatsu, Yuji*; Nakamura, Kazuhito*; Chikazawa, Takahiro*; Hirasawa, Izumi*
Journal of Nuclear Science and Technology, 53(4), p.521 - 528, 2016/04
Times Cited Count:3 Percentile:25.75(Nuclear Science & Technology)Niimura, Nobuo; Arai, Shigeki; Kurihara, Kazuo; Chatake, Toshiyuki*; Tanaka, Ichiro*; Bau, R.*
Cellular and Molecular Life Sciences, 63(3), p.285 - 300, 2006/02
Times Cited Count:41 Percentile:36.92(Biochemistry & Molecular Biology)Neutron diffraction provides an experimental method of directly locating hydrogen atoms in proteins and DNA oligomers. Three different types of high resolution neutron diffractometers for biological macromolecules have been constructed in Japan, France and the U.S.A., and they have all been actively used in recent years to determine the crystal structures of numerous proteins. Examples include the detailed geometries of hydrogen bonds, information on H/D exchange in proteins, the unambiguous location of protons, the role of key hydrogen atoms in enzymatic activity and thermostability, and the dynamical behavior of hydration structures, all of which have been extracted from these structural results and reviewed in this article. Other important techniques, such as the optimization of growth of large single crystals using phase diagrams, the preparation of fully deuterated proteins, the introduction of cryogenic techniques to neutron protein crystallography, and the establishment of a "hydrogen and hydration in proteins" database, will also be described in this paper.
Honjo, Eijiro; Tamada, Taro; Maeda, Yoshitake*; Koshiba, Takumi*; Matsukura, Yasuko*; Okamoto, Tomoyuki*; Ishibashi, Matsujiro*; Tokunaga, Masao*; Kuroki, Ryota
Acta Crystallographica Section F, 61(8), p.788 - 790, 2005/08
Times Cited Count:7 Percentile:54.65(Biochemical Research Methods)Granulocyte colony-stimulating factor (GCSF) receptor receives signals for regulating the proliferation and differentiation of the precursor cells of granulocytes. The complex composed of two GCSFs and two GCSF receptors was crystallized. The crystal of the complex was grown in 1.0 M sodium formate and 0.1 M sodium acetate (pH4.6). It belongs to the space group 4
2
2 (or its enantiomorph
4
2
2) with unit cell dimensions of
=
= 110.1
,
= 331.8
. However, the diffraction data from the crystal beyond 5
resolution could not be collected. Since the heterogeneity of GCSF receptor seems to interrupt growth of good quality crystals, the GCSF receptor was fractionated by achromatography. Crystals of GCSF/fractionated GCSF receptor complex were grown as a new crystal form in 0.2 M ammonium phosphate. The new crystal diffracts beyond 3.0
resolution and belongs to space group
3
21 (or its enantiomorph
3
21) with unit-cell parameters
=
= 134.8,
= 105.7
.
Niimura, Nobuo; Arai, Shigeki; Kurihara, Kazuo; Chatake, Toshiyuki*; Tanaka, Ichiro*; Bau, R.*
Hydrogen- and Hydration-Sensitive Structural Biology, p.17 - 35, 2005/00
At the JAERI, we have constructed several high-resolution neutron diffractometers dedicated to biological macromolecules (called BIX-type diffractometers), which use a monochromatized neutron beam and a neutron imaging plate detector. In this paper, we review several interesting results regarding hydrogen positions and hydration in proteins, obtained using the two BIX-type diffractometers in JAERI. The general subject of neutron protein crystallography has been reviewed by several authors, and several selected topics have been discussed.
Suzudo, Tomoaki
Physica A, 343, p.185 - 200, 2004/11
Times Cited Count:22 Percentile:70.50(Physics, Multidisciplinary)This paper proposes a class of 2-dimensional asynchronous cellular automata with conservation of mass, for the formation of patterns in groups, and describes the merits given by this methodology. A cellular automaton rule causing a specified kind of pattern was designed manually. Thanks to this realistic modeling method reflecting nature, the mechanism of pattern formation was found to be similar to real chemical processes. A search technique using genetic algorithm is applied to find pattern-forming CAs, and it successfully find a few types of spontaneous pattern formations. This technique is expected to be applied to a wide range of potential studies related to self-organization.
Kurihara, Kazuo; Tanaka, Ichiro*; Niimura, Nobuo
Nihon Kessho Gakkai-Shi, 46(3), p.193 - 200, 2004/05
Neutron diffraction provides an experimental method of directly locating hydrogen atoms in proteins and nucleic acids, and the development of the neutron imaging plate (NIP) became a breakthrough event in neutron protein crystallography. A high-resolution neutron diffractometers dedicated to biological macromolecules (BIX-3, BIX-4) with the NIP have been constructed at Japan Atomic Energy Research Institute. The detailed structure of the diffractometer and the systematic procedure of the neutron diffraction experiment from the crystallization of a large single crystal to the data collection and the data processing, and the future prospect of the neutron diffractometry in proteins will be presented.
Matsubara, Masakazu*; Yamaki, Tetsuya; Ito, Hisayoshi; Abe, Hiroaki*; Asai, Keisuke*
Japanese Journal of Applied Physics, Part 2, 42(5A), p.L479 - L481, 2003/05
Pulsed laser ablation with a KrF excimer laser was used to prepare fine particles of titanium dioxide (TiO). The ablation in an atmosphere of Ar and O
(5:5) at total pressures of
1 Torr led to the formation of TiO
nanoparticles composed of anatase and rutile structures without any suboxides. The weight fraction of the rutile/anatase crystalline phases was controlled by the pressure of the Ar/O
gas. The TiO
nanoparticles had a spherical shape and their size, ranging from 10 and 14 nm, also appeared to be dependent on the ambient pressure.
Zhang, Z.; Narumi, Kazumasa; Naramoto, Hiroshi
Journal of Physics; Condensed Matter, 13(22), p.L425 - L481, 2001/06
no abstracts in English
; Fujine, Sachio; Asakura, Toshihide; Murazaki, Minoru*; ; Sakakibara, Tetsuro*;
JAERI-Research 99-027, 37 Pages, 1999/03
no abstracts in English
; ; Kikuchi, Kenji; ; Miura, Takayuki*
Proc. of 4th Int. Conf. on Recrystallization and Related Phenomena (REX'99), p.283 - 288, 1999/00
no abstracts in English
; ; ; Tsuji, Hirokazu; ; Shindo, Masami
Mater. Sci. Eng., A, 234-236, p.1087 - 1090, 1997/00
no abstracts in English
; Ikeda, Shigetoshi*; Seguchi, Tadao; Tabata, Yoneho*
Radiation Physics and Chemistry, 50(5), p.519 - 522, 1997/00
Times Cited Count:26 Percentile:86.06(Chemistry, Physical)no abstracts in English
Kurata, Yuji; Nakajima, Hajime
Journal of Nuclear Materials, 228, p.176 - 183, 1996/00
Times Cited Count:12 Percentile:69.95(Materials Science, Multidisciplinary)no abstracts in English
; Ikeda, Shigetoshi*; Seguchi, Tadao; Tabata, Yoneho*
Material Chemistry 96: Proc. of Int. Symp. on Material Chemistry in Nuclear Environment, 0, p.755 - 761, 1996/00
no abstracts in English
Sasase, Masato*; ; Yamaki, Takahiro*; Takano, Ichiro*;
Thin Solid Films, 281-282, p.431 - 435, 1996/00
Times Cited Count:6 Percentile:38.33(Materials Science, Multidisciplinary)no abstracts in English
Kurata, Yuji; Nakajima, Hajime
JAERI-Research 94-004, 30 Pages, 1994/08
no abstracts in English