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An analytical study of acoustically perturbed Brillouin active magnetized semiconductor plasma has been reported. In the present analytical investigation, the lattice displacement, acousto-optical polarization, susceptibility, acousto-optical gain constant arising due to the induced nonlinear current density and acousto-optical process are deduced in an acoustically perturbed Brillouin active magnetized semiconductor plasma using the hydrodynamical model of plasma and coupled mode scheme. The influence of wave number and magnetic field has been explored. The analysis has been applied to centrosymmetric crystal. Numerical estimates are made for n-type InSb crystal duly irradiated by a frequency doubled 10.6 μm CO2 laser. It is found that lattice displacement, susceptibility and acousto-optical gain increase linearly with incident wave number and applied dc magnetic field, while decrease with scattering angle. The gain also increases with electric amplitude of incident laser beam. Results are found to be well in agreement with available literature. [ABSTRACT FROM AUTHOR]

In this work, the process of polymer-polymer interdiffusion is studied with an acoustic method. The acoustic responses of polystyrene bilayers are analyzed in the frequency domain. Frequency and width of the resonances are processed. Two types of algorithm are used to characterize the resonances: a first-order background method and a second-order background method. Correlations between annealing time, thickness of the interphase and width of the resonance are shown. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

It has been shown that conical PZT transducers based on a design originally developed at National Institute for Standards and Technology in the USA can be used as point transmitters over the frequency range of interest in typical acoustic emission (AE) measurements. They should therefore be suitable for use as standard sources to calibrate structures so that absolute AE source strengths can be determined. It has been shown that measurements of the response of the transmitting transducer backing can be used to assess the coupling efficiency, and hence to remove concerns about inconsistent coupling affecting the calibration measurements. The results indicate that the variation of the backing response with coupling is due to a shift in the resonance frequencies of the transducer with the mechanical load impedance. If other transducers can be shown to behave in a similar fashion this effect could be used to measure coupling in standard acoustic emission and ultrasonic transducers. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

This talk reviews the first results from MAXIMA and the scientific implications of the combined MAXIMA and BOOMERANG data sets. The key piece of science is that both experiments independently observe the first acoustic peak in CMB angular power spectrum at a value l ∼ 200 and with a width which are compatible with a flat universe and inflation. Both experiments also observe a positive signal which is lower than that previously expected for the second acoustic peak region. A natural economical explanation is that the density of baryons is slightly but noticeably higher than that determined through Big Bang Nucleosynthesis theory. [ABSTRACT FROM AUTHOR]

The following is an edited transcript of a recorded discussion session on the topic of "Molecular and Cellular Mechanics". The discussion, moderated by the author, took place at the 12th International Workshop on the Mechanics of Hearing held at Cape Sounio, Greece, in June 2014. All participants knew that the session was being recorded. In view of both the spontaneous nature of the discussion and the editing, however, this transcript may not represent the considered or final views of the participants, and may not represent a consensus of experts in the field. The reader is advised to consult additional independent publications. [ABSTRACT FROM AUTHOR]