Metamaterial absorbers are photonic structures composed of an array of sub-wavelength metallic patterns. Results in literature are usually based on structures of nominal dimensions, despite the significant effect of fabrication tolerances on performance. This research aims to identify the main sources of uncertainty and to investigate their effect, notably that of an irregular surface quality (...

The diffusion of substrate material into absorbing layer and oxidation metal or cermet nanoparticles at high temperatures are known as inevitable problems the solar selective absorbers. In this study, we consider use textured stainless steel (SS) surface coated with a protective AlCr oxide temperature absorber. SS was prepared by ion etching techniques deposited RF magnetron sputtering. absorpt...

We present a complete catalogue of 27 O VI absorbers at low redshift (0.12 < z < 0.5) from a blind survey of 16 QSO echelle spectra in the HST/STIS data archive. These absorbers are identified based only upon matching line profiles and the expected doublet ratio between the λλ 1031, 1037 transitions. Subsequent searches are carried out to identify their associated transitions. Here we present a...

Recent observations suggest the incidence of strong intervening Mg ii absorption systems along the line-of-sight to gamma ray burst (GRB) afterglows is significantly higher than expected from analogous quasar sightlines. One possible explanation is a geometric effect, arising because Mg ii absorbers only partially cover the quasar continuum regions, in which case Mg ii absorbers must be conside...

The H I Parkes All Sky Survey (HIPASS) galaxy catalogue is cross-correlated with known low redshift, low column density (NHI < 10 cm) Lyman-α absorbers from the literature. The redshift-space correlation is found to be similar in strength to HIPASS galaxy self-clustering (correlation length s0,ag = 6 ± 4 and s0,gg = 3.1 ± 0.5 h −1 100 Mpc respectively). In realspace the cross-correlation is str...

The 2.5 GeV Synchrotron Light Source ANKA is now under construction at the Research Center in Karlsruhe. For a designed current of 400 mA, a power of 250 kW is radiated by the circulating e-beam in the 16 dipole magnets. 90% of the synchrotron radiation (SR) is absorbed by the 32 crotch absorbers in the dipole and the adjacent ante chamber, the remaining 10 % by distributed absorbers in the str...

In the quest for higher efficiency and lower cost solar energy conversion devices, new light absorber materials are being intensively researched. With their attractive optical electrical properties, metal chalcogenide have emerged as promising candidates these next-generation absorbers. this review, we survey studies on absorbers having a simple binary composition, namely, Cu2S, SnS, GeSe, WSe2...

A loudspeaker installed in a room acts as a coupled system where the room properties typically dominate the rate of energy decay. At high frequencies, typically above a few hundred hertz, passive methods of controlling the rate and properties of this energy decay are straightforward and well established. Individual strong reflections are broken up by diffusing elements in the room or trapped in...

An elastomer is a polymer with the property of viscoelasticity, generally having notably low Young's modulus and high yield strain compared with other materials.  Elastomers, in particular rubbers, are used in a wide variety of products ranging from rubber hoses, isolation bearings, and shock absorbers to tires. Rubber has good properties and is thermal and electrical resistant. We used carbon ...