Results from a numerical study examining micro-/macrorelations linking local geometry parameters to sound absorption properties are presented. For a hexagonal structure of solid fibers, the porosity phi, the thermal characteristic length Lambda('), the static viscous permeability k(0), the tortuosity alpha(infinity), the viscous characteristic length Lambda, and the sound absorption coefficient...

Irradiated materials that are weakly absorbing are heated by both diffusive and direct heating. This creates various internal heating patterns and introduces the possibility of developing hot spots in the specimen that are not detected by surface monitoring. These systems are investigated for a single instantaneous radiation pulse and for a chain of such pulses. Characteristic times are identif...

Microwave absorbing materials (MAMs) are paving the way for exciting applications in electromagnetic (EM) pollution precaution and national defense security, as they offer an advanced alternative to conventional reflection principles to fundamentally eliminate the EM waves. Conjugated polymer (CP)-based composites appear as a promising kind of MAM with the desirable features of low density and ...

New procedure for permittivity and permeability extraction of two composite (dielectric matrix + magnetic inclusions), isotropic and homogeneous absorbing material is presented. It calculates mentioned parameters by fitting measured transmission data with Debye relaxation model (for complex dielectric permittivity extraction) and with Lorenzian resonant model (for complex permeability extractio...

The design and realization of graphene based wideband electromagnetic (EM) absorbing textiles are becoming primary interest. Hence, the development new conductive coatings to be cast onto commercial is crucial. In this article, we propose that conjugate outstanding EM properties at radiofrequency with low-weight, flexibility, cost-effectiveness, washability. With purpose, an innovative producti...

A thermally enhanced method for improving photoacoustic imaging depth and signal-to-noise (SNR) ratio is presented in this paper. Experimental results showed that the maximum imaging depth increased by 20% through raising the temperature of absorbing biotissues (ex-vivo beef muscle) uniformly from 37 to 43°C, and the SNR was increased by 8%. The parameters making up the Gruneisen constant were ...

It is shown that thin mushroom layers (high-impedance surfaces realized as regular arrays of small patches at a small distance from a metal surface) can be used as radar-absorbing structures whose performance does not change with the incidence angle for TM-polarized waves. The key role of the vias connectors between the patches and the ground plane is explained, and potential performance demons...

Modern military and civic applications require broadband microwave multilayer radar absorbing material (MRAM), which typically consists of multiple layers that increase the thickness platforms like aircraft, ships, vehicles, thereby adding to their weight. To address this, MRAM design methods strive optimize layer parameters reduce thickness. In this article, we emphasize importance cost functi...