Knowing the thermal expansion of a material and the correlation analysis of the photoacoustic signals, it is possible to obtain the phase transition temperature and a qualitative curve of the specific heat at constant pressure (Cp) for ceramic materials. This analysis was applied to a BaTiO3 ferroelectric ceramic and a good agreement with previously published Cp versus temperature curves was obtained. Additionally, the phase transition temperature and the Cp curve of a samarium-doped lead titanate ceramic (Pb0.88Sm0.08TiO3) are presented. The phase transition temperature of the Pb0.88Sm0.08TiO3 obtained with this technique was corroborated with classical differential thermal analysis and dielectric permittivity measurements.

A novel approach to specify symmetries and main optical axes in anisotropic polymeric films is proposed. This method is based on the analysis of the optical absorption via the pulsed laser photoacoustic (PLPA)- technique in a common polarizer film, while rotating the polarizer axis at normal incidence. Since the PLPA-signals are directly proportional to the optical absorption, it is shown that a symmetric and complementary Malus's law can be obtained over full root mean square (RMS)- and correlation (CA)-analysis of the PLPA-signals. Such data processing reveals the main material directions of the constituting film molecules defining the symmetry structure of the sample. PLPA-results were compared to the pure optical transmission experiments and show unambiguous information, allowing this technique to be used in nonstandard and opaque polymeric films, where the analysis of the optical measurements represents a difficult task, and in general, in anisotropic media.

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Our data suggest more engagement of neural networks of the right hemisphere are involved in Zapotec language discrimination.

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