Lutetium aluminum garnet activated by cerium (LuAG:Ce) materials containing functional materials (SiO2 and MgO) were prepared. These materials are used in LEDs, and they require a high thermal conductivity in order to minimize thermal aging. The functional materials were added in order to increase the thermal conductivity, as well as the luminescent properties of these materials. It was found that SiO2 did not improve the luminescent properties, but MgO ...
The thermal properties (thermal conductivity, thermal diffusivity, and specific heat) were measured for igneous and sedimentary rocks at room temperature and atmospheric pressure. The thermal properties of the igneous rocks, dunite and gabbro, were then measured at temperatures ranging from 293 K to 483 K and 293 K to 443 K, respectively. A predictive model was then developed for estimating the effective thermal conductivity of porous media using the thermal conductivities of the solid ...
The thermal and mechanical properties of concrete in which normal weight aggregate has been substituted with lightweight aggregates were investigated. The properties were found to be dependent on the volume fraction of the lightweight aggregate, as well as on the nature and quality of the aggregate. The addition of lightweight aggregates resulted in a decreased thermal conductivity, as well as a decreased thermal diffusivity in all samples. The compressive strength ...
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 ...
Two series of co-doped mifit-layered cobaltites were prepared with compositions of Ca3-xYbxCo4-yAgyO9+delta and Ca3-xEuxCo4-yAgyO9+delta. All of the samples exhibited an increasing thermopower as temperature was increased up to a temperature of 700 K. The sample with the highest power factor and figure of merit was Ca2.95Eu0.05Co3.95Ag0.05O9+delta....