A linear time-domain thermoelastic (photothermoacoustic) theory of a composite solid-liquid geometry has been developed. The theory includes multiple interreflections at all interfaces, acoustic diffraction and viscosity effects, and natural mixed, rigid, and free boundary conditions at the solid surface where laser-pulse incidence occurs (air-polystyrene interface). The theory was applied to experimental pressure-wave pulses from a Nd:YAG laser in a polystyrene well target and water system used for photomechanical drug delivery studies. Good fits of the linear theory to tripolar experimental pressure waveforms were possible at laser-pulse irradiances Շ100 MW/ cm 2 , especially at distances ഛ5 mm from the solid-fluid interface. It was further determined from the combined theoretical and experimental approach that the onset of significant hydrodynamic nonlinearity in the water appears for laser-pulse irradiances in the 165-MW/ cm 2 range, especially at axial distances z ϳ 8 mm, as expected theoretically from the laser-ablation-induced nonlinearity of stress-wave propagation in the solid-water system.
The optimized geometrical parameters, energy band structures, density of states, thermodynamic properties of the group-IIIA elements X-doped (X ¼ Ga, In, Tl) VO 2 have been studied using first-principles calculations. The effect of the impurities on the phase transition temperature (T c ) is also investigated. The substitutional site of V atom and the octahedral interstitial site are considered as the doping positions. Our calculated results show that the hybridization between electronic orbitals of different atoms causes a decrease of E g2 value by shifting the valence band toward the higher energy and the conduction band toward the lower energy when X is doped at the substitutional site of V atom (i.e., X@V). For the interstitial doped system (i.e., X@i), the Fermi level enters the conduction band to show the metallic property. The T c of X-doped (X ¼ Ga, In, Tl) VO 2 is reduced compared to that of pure VO 2 . Indium@V could be a promising element to reduce T c of VO 2 as a smart window material.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.