The authors present the synthesis of hollow silica nanospheres (HSNSs) by a template-assisted approach using polystyrene nanospheres as templates. These nanospheres could potentially be used as nano insulation materials due to their low thermal conductivity ~0.02 W/m K. The authors also examined the environmental footprint of these nanospheres by life cycle assessment, and it was found that they possess a high embodied energy. It was thus suggested that new synthetic ...
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 reaction to fire properties of three commercial coatings designed for steel structures were investigated. The coatings in this study were covering a glass fiber-reinforced epoxy composite. It was determined that the thermal barrier effectiveness of these coatings was dependent on the degree of expansion and the thermal conductivity of the expanded char. Using these two parameters, the required thickness of a coating that can enable a structure to withstand ...
The authors present a method of preparation of TiO2 nanotubes by alkaline treatment (with NaOH) of TiO2 particles followed by acid-washing and annealing treatment. Theoretical and experimental studies on the thermal conductivity of TiO2 nanotubes is also presented. The thermal conductivity values determined experimentally matched well with theoretical values obtained. It was found that TiO2 nanotubes had a lower thermal conductivity than the original TiO2 particles. This phenomenon was attributed ...
The authors describe a synthesis method for a series of pulverized expandable graphite (pEG)/melamine-formaldehyde (MF) resin core-shell structure particles. The particles are also added into rigid polyurethane foams (RPUF) to characterize the flame-retardant, mechanical, and thermal insulation properties of the RPUF/pEG-MF composites. It was found that the pEG/MF particles showed good flame-retardant performance in the composites by providing a physical barrier effect....
