High-quality bismuth telluride crystals having a thickness of only a few atoms were prepared by a method similar to that for graphene mechanical exfoliation. The potential for these materials to be used as thermoelectric materials was then investigated. It was found that the properties of these materials could be fine-tuned by altering the thickness, or the sequence of atomic planes. “Stacked superlattices” were formed using these atomic films, and these ...
Low-density microcellular non-isocyanate polyurethane (NIPU) foams were prepared using biological compounds and carbon dioxide. The morphology of these foams was investigated by scanning electron microscopy (SEM), and the thermal conductivity was determined using the transient plane source (TPS) method. It was concluded that a study needed to be undertaken to determine how to fine tune the morphology of the foams in order to decrease the thermal conductivity of the foams....
The potential for the use of multi-walled carbon nanotubes (MWCNTs) for the adsorption of ammonia in solid-gas adsorption refrigeration applications has been investigated by experimental determination of ammonia adsorption properties, as well as the thermal conductivity of a composite adsorption material. In addition to this, two models for estimating the adsorption of ammonia on MWCNTs were evaluated. It was determined that the adsorption amount of ammonia on MWCNTs at equilibrium ...
Si-SiC composite foams were prepared using tannin-based foams as templates. The foams were prepared by four different methods for the determination of which method would best produce a foam with a pore size under 200 µm. The foam samples were characterized by SEM, XRD, and Raman spectroscopy, and the thermal conductivity of one of the foams was investigated by the transient plane source method. It was found that direct infiltration of ...
Ambient pressure dried hydrophobic silica aerogel monoliths were prepared via simultaneous solvent exchange and surface modification in order to minimize volume shrinkage and density. At room temperature, the obtained silica aerogels had a low density of 0.096 g/cm3, a high surface area and hydrophobicity, and a low thermal conductivity of 0.0217 W/m·K. The effect of heating on these properties was also determined. After the aerogel had been heated to 300...
