Hitoshi MIURA
- Division
- Mathematical and Material Science, Associate Professor
- Academic Degree
- Ph.D.
| Research Field | Planetary Science, Theory of Crystal Growth |
|---|---|
| Keywords | Numerical Simulations, Meteorites, Early Solar System, Formation of Planetary System, Chondrule, Phase-field method, GPU Computing |
| Current Research Topics | (1) Evolution of Solid Materials in Early Solar System: There are various crystals on the Earth at present. Extra-terrestrial materials such as meteorites also contain crystalline grains. Oh the other hand, it has been revealed that almost all solid materials in inter-stellar region are amorphous. When, where, and how were the amorphous materials crystallized during the formation of Sun and planetary system? We are investigating the dust heating mechanism in the proto-planetary gas disk using theoretical modeling and numerical simulations. (2) Morphologies and Zoning profiles of Rock-forming Minerals: Rock-forming minerals have formed in cooling magmas. The morphologies and compositional zoning structures reflect the growth environments such as temperature, chemical composition, pressure, and the variations. How were the morphologies and zoning structures affected by the growth conditions? We develop mathematical models of the growth of minerals to investigate the minerallization process. (3) Step Dynamics on Surface of Growing Crystal: The facet face of crystals seems flat, however, there are many atomic-scale steps of about 1nm in height. During crystal growth, atoms and/or molecules in solution are transported onto the crystal surface and incorporated at the steps. However, if there are some impurities in the solution, they may be adsorbed at the steps and prevent the crystal growth. We investigate the effect of impurities on the step dynamics using mathematical models. (4) Colloidal Crystals and Inter-particle Interaction: A colloidal crystal is an ordered array of colloid particles. On the formation of the ordered structure, an inter-particle interaction between colloid particles plays an important role. We are numerically investigating the dynamics of a small-number cluster in the non-equilibrium system by Brownian dynamics (BD) method. |
| Selected Publications | (Original Articles) The asteroid 162173 Ryugu: a cometary origin. The Astrophysical Journal Letters 925, L15 (2022) Phase-field model for growth and dissolution of a stoichiometric compound in a binary liquid, Physical Review E 98, 023311 (2018) Comprehensive study of thermal desorption of grain-surface species by accretion shocks around protostars, The Astrophysical Journal 839:47 (16pp) (2017) Numerical study of impurity-induced growth hysteresis on a growing crystal surface, Crystal Growth & Design 16, 2033-2039, (2016) Phase-field modeling of step dynamics on growing crystal surface: Step pinning induced by impurities, Crystal Growth & Design 15, 4142-4148 (2015) Phase-field modeling of step dynamics on growing crystal surface: direct integration of growth units to step front, Crystal Growth & Design 15, 2165-2175 (2015) A New Estimate of Chondrule Cooling Rate Deduced from an Analysis of Compositional Zoning of Relict Olivine, The Astronomical Journal 147, 54 (2014) Role of impurity on growth hysteresis and oscillatory growth of crystals, Crystal Growth & Design 13, 3588-3595 (2013) Anisotropy function of kinetic coefficient for phase-field simulations: Reproduction of kinetic Wulff shape with arbitrary face angles, Journal of Crystal Growth 367, 8-17 (2013) A new constraint for chondrule formation: condition for the rim formation of barred-olivine textures, Earth, Planets and Space 63, 1087-1096 (2011) Phase-field simulation for crystallization of a highly supercooled melt droplet in levitation environment, Journal of Applied Physics 108, 114912 (2010) Formation of cosmic crystals in highly-supersaturated silicate vapor produced by planetesimal bow shocks, Astrophysical Journal 719, 642-654 (2010) Origin of three-dimensional shapes of chondrules. I: Hydrodynamics simulations of rotating droplet exposed to high-velocity rarefied gas flow, Icarus 197, 269-281 (2008) Fragment-Collision Model for Compound Chondrule Formation: Estimation of Collision Probability, Icarus 194, 811-821 (2008) Shock-Wave Heating Model for Chondrule Formation: Hydrodynamic Simulation of Molten Droplets exposed to Gas Flows, Icarus 188, 246-265 (2007) Shock-Wave Heating Model for Chondrule Formation: Prevention of Isotopic Fractionation, Astrophysical Journal 651, 1272-1295 (2006) |