Molecular-dynamics simulations and in situ experimental observations of the melting and equilibrium structure of the crystalline Si(100)-melt interface are described. The equilibrium interface is structured, exhibiting facets established on (111)planes. PACS numbers: 68.55.Rt, 64.70.Dv, 68.45.KgThe study of the solid-vapor and solid-liquid interfaces has attracted a recent surge of interest because of improved experimental and theoretical techniques for probing phenomena such as surface melting, surface roughening, and interface morphology. In particular,

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In Al-Ti-Mg killed steels, the use of complex deoxidation products, which act as heterogeneous nucleation sites for fine intragranular ferrite, has been acknowledged as an effective way for grain refinement. In this study, we investigated the interaction between Mn solute atoms and different oxide inclusions (such as MgO, MgTi2O4, MgTiO3, Ti2O3, Ti3O5, Al2O3, MgAl2O4) experimentally and using first-principles calculations, to identify the oxides that can effectively lead to the formation of local Mn-depleted zones promoting the nucleation of intragranular ferrite. The results show that MgTi2O4, MgTiO3 are effective for partition of Mn atoms into oxides, while MgO, Al2O3, MgAl2O4 are ineffective for the formation of local Mn-depleted zones. Furthermore, the calculations show that Mn atoms exist as a simple solute by 2 replacing Mg atoms in MgO, MgTi2O4 and MgTiO3. Except by forming complex Ti-Mn oxides, such as MnTi2O4 and MnTiO3, Mn atoms can also exist as a simple solute in Ti2O3 by occupying vacancy positions in their crystals. Ti3O5 oxides cannot absorb Mn atoms by replacing Ti atoms in it, meanwhile, the occupying vacancy pattern is not the main reason for Ti3O5 oxides absorb Mn atoms.

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Influence of bath temperature and pH on the structure of electrodeposited cobalt nanowires To fully understand the mechanism of forming fcc Co in electrodeposition, the effect of bath temperature and pH on the structure of electrodeposited Co nanowires is studied by means of X-ray diffraction and scanning electron microscopy. At -3.0 V and pH 2.5, the fraction of fcc Co decreases with increasing temperature, ranging from 1 (25 8C, pure fcc Co) to 0 (45 8C, pure hcp Co). The formation of hcp Co can be attributed to larger critical clusters formed at higher temperatures. The pH value has no appreciable effect on the formation of fcc Co nanowires. This is because the H adatoms produced at the cathodic surface can penetrate quickly through the thin Au film and desorb into air.

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Three-dimensional Darcy–Forchheimer flow of nanoliquid due to a rotating disk subject to multiple slip conditions is examined in this study. Thermophoresis and Brownian motion along with heat and mass transfer are incorporated. Slip conditions of velocity, concentration, and temperature are executed. Similarity results are established via MATLAB routine bvp4c. Graphs of velocities, temperature, and concentration are sketched to discuss the impacts of several influential parameters. Numerical values of skin frictions and local Sherwood and Nusselt numbers are calculated and inspected. Our findings display that concentration and temperature are enhanced for larger thermophoresis parameter.

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