The laser floating zone method was used to prepare Pb doped Bi2-xPbxBa2Co2Oy thermoelectric materials with x=0, 0.2, 0.4, and 0.6. The highest power factor reported was obtained at 650oC for the 0.2 Pb doped samples. This value was higher than that for pure laser grown Bi2Ba2Co2Oy materials. The thermal conductivity was decreased, as is desired in thermoelectric materials....
The authors prepared silica aerogel/polyurethane composites by two different methods for the comparison of the two methods. The objective was to study the thermal insulation and hydrophobic properties of the composites to evaluate their potential for use as fabric membranes. It was found that the composites are better thermal insulators than polyurethane alone, and that they also have improved hydrophobic properties. It was also determined that the thermal conductivities ...
In an effort to enhance heat transfer in the laminar flow regime of a heating duct, TiO2 and SiO2 nanoparticles were added to water to create nanofluids with a higher thermal conductivity than that of the water alone. Twist-tape was also used to enhance heat transfer within the duct. The thermal conductivities of the nanofluids were measured using the Transient Plane SourceĀ instrument. It was found that the use of ...
The potential for the use of silica aerogels doped with TiO2 nanowires as thermal insulators was evaluated. It was found that the TiO2-doped aerogels showed good thermal insulation properties and that other desirable properties were retained upon the addition of TiO2 nanowires....