Solar cookers are aimed at reducing pollution and desertification in the developing world. However, they are often disregarded as they do not give users the ability to cook after daylight hours. The Wilson solar cooker is a solar cooker designed to address this problem by converting solar energy and storing that energy as heat in the form of molten salt (lithium nitrate). This thesis involved r...

Nanostructured optical coatings with tailored spectral absorption properties are of interest for a wide range of applications such as spectroscopy, emissivity control, and solar energy harvesting. Optical metamaterial absorbers have been demonstrated with a variety of customized single band, multiple band, polarization, and angular configurations. However, metamaterials that provide near unity ...

We derive expressions for the spectral emissivity and absorptivity of acoustic radiation by low Mach number (M ~ 1) turbulent fluids. The emissivity and absorptivity depend on the manner in which the turbulence is excited. We consider three types of turbulence. The first is free turbulence, that is, turbulence which is not subject to external forces. The second and third examples are special ca...

Systematic density functional theory studies and model analyses have been used to show that the band gap of iron pyrite (FeS(2)) can be increased from ~1.0 to 1.2-1.3 eV by replacing ~10% of the sulfur atoms with oxygen atoms (i.e., ~10% O(S) impurities). O(S) formation is exothermic, and the oxygen atoms tend to avoid O-O dimerization, which favors the structural stability of homogeneous FeS(2...

Proton acceleration from nanometer thin foils with intense laser pulses is investigated experimentally. We analyzed the laser absorptivity by parallel monitoring of laser transmissivity and reflectivity with different laser intensities when moving the targets along the laser axis. A direct correlation between laser absorptivity and maximum proton energy is observed. Experimental results are int...

We estimate high optical absorption in silicon thin film photovoltaic devices using triangular corrugations on the back metallic contact. We computationally show 21.9% overall absorptivity in a 100-nm-thick silicon layer, exceeding any reported absorptivity using single layer gratings placed on the top or the bottom, considering both transverse electric and transverse magnetic polarizations and...

High-emissivity coatings are often used on the surfaces of solar probes to block heat from sun. Therefore, improving thermal control ability is standard for determining quality coatings. In this study, MgO was doped into Al2O3 improve and analyse effect different doping contents. The absorptivity infrared (IR) emissivity ratio (α/ε) evaluate results showed that 5 wt.% content best choice. main ...

Thermal management systems for space equipment commonly use static solutions that do not adapt to environmental changes. Dynamic control of radiative surface properties is one way to respond to environmental changes and to increase the capabilities of spacecraft thermal management systems. This paper documents an investigation of the extent to which origamiinspired surfaces may be used to contr...