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A generalized enthalpy based equation of state, which includes thermal electron excitations explicitly, is formulated from simple considerations. Its application to obtain Hugoniot of materials needs simultaneous evaluation of pressure-volume curve and temperature, the latter requiring solution of a differential equation. The errors involved in two recent papers [Huayun et al., J. Appl. Phys. 92, 5917 (2002); 92, 5924 (2002)], which employed this approach, are brought out and discussed. In addition to developing the correct set of equations, the present work also provides a numerical method to implement this approach. Constant pressure specific heat of ions and electrons and ionic enthalpy parameter, needed for applications, are calculated using a three component equation of state. The method is applied to porous Cu with different initial porosities. Comparison of results with experimental data shows good agreement. It is found that temperatures along the Hugoniot of porous materials are significantly modified due to electronic effects. [ABSTRACT FROM AUTHOR]

The evolution of the surface temperature of flash-illuminated layered structures was studied by means of photothermal radiometry, the finite element method, and the Green’s formalism. The potential of a simple tabletop experiment to extract the sequence and thickness of the layers was investigated. Keeping the complexity low, only one parameter can be determined independently, for instance the absolute value and small variations of the top layer thickness. Our method is straightforward, accurate, and well-suited for online thickness detection. [ABSTRACT FROM AUTHOR]