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The aim of this paper is to present and validate rain attenuation time series synthesizers relying on the Maseng-Bakken principle for terrestrial links in tropical areas. Data obtained in experimental measurements at fou...

This paper presents an experimental comparative study of iron losses obtained by means of the Epstein frame, Ring Core and dynamometer tests with non-oriented electrical steel samples. The comparisons are qualitative and...

Abstract In this paper, the behavior of Coplanar Waveguide (CPW) fed SIERPINSKI curve fractal antenna is studied. The results show that there is a relationship between the iteration number and the resonance frequencies. ...

Abstract The ground plane plays an important role on the performance of a planar inverted-F antenna (PIFA). In this regard, the ground plane modification using slots is proposed in this research to obtain a dual band ant...

Abstract We investigate a three-dimensional (3D) reciprocal invisibility cloak with a multilayered structure based on coordinate transformation theory and complementary media. There has been considerable research on invi...

In this paper, a semi-empirical method for the prediction of rain attenuation in slant paths and terrestrial links is proposed. The method uses the same simplified model of equivalent rain cell that is the basis for the ...

Abstract We proposed and analyzed a planar narrow-band absorber based on a bi-layer metal/dielectric structure. The planar absorber uses the Fabry-Pérot resonance and the inherent loss of the metals, for maximum light a...

Many potential applications have been proposed for carbon nanotubes, including conductive and high-strength composites; energy storage and energy conversion devices; sensors; field emission displays and radiation sources...

The energy costs associated with separating tightly bound excitons (photoinduced electron-hole pairs) and extracting free charges from highly disordered low-mobility networks represent fundamental losses for many low-cos...

Organic-inorganic perovskites have shown promise as high-performance absorbers in solar cells, first as a coating on a mesoporous metal oxide scaffold and more recently as a solid layer in planar heterojunction architect...

Novel physical phenomena can emerge in low-dimensional nanomaterials. Bulk MoS(2), a prototypical metal dichalcogenide, is an indirect bandgap semiconductor with negligible photoluminescence. When the MoS(2) crystal is t...

Materias / palabras clave: Graphene; Materials science; Microscale chemistry; Chemical vapor deposition; Nanotechnology; Wafer; Sheet resistance; Graphene oxide paper; Electrode; Graphene foam; Thin film; Optoelectronics

We show that microstructures built from nonmagnetic conducting sheets exhibit an effective magnetic permeability /spl mu//sub eff/, which can be tuned to values not accessible in naturally occurring materials, including ...

Metal halides perovskites, such as hybrid organic-inorganic CH3NH3PbI3, are newcomer optoelectronic materials that have attracted enormous attention as solution-deposited absorbing layers in solar cells with power conver...

The carrier collection efficiency (η c ) and energy conversion efficiency (η e ) of polymer photovoltaic cells were improved by blending of the semiconducting polymer with C 60 or its functionalized derivatives. Compos...

Room-temperature ultraviolet lasing in semiconductor nanowire arrays has been demonstrated. The self-organized, oriented zinc oxide nanowires grown on sapphire substrates were synthesized with a simple vapor transport a...

Semiconductor nanocrystals were prepared for use as fluorescent probes in biological staining and diagnostics. Compared with conventional fluorophores, the nanocrystals have a narrow, tunable, symmetric emission spectrum...