Contemporary Examples. 1  He campaigned and governed in poetry, and we are all the richer for it. 2  Its essays, criticism, reportage, and poetry are not âproduct.â. 3  Laskey, who earned a degree in psychology, enjoys painting and poetry. 4  poetry would be too obvious, too âportrait of the artist as a young nuisanceâ.
Low emissivity - Definition. 1  Emissivity is the value given to materials based on the ratio of heat emitted compared to a perfect blackbody, on a scale from zero to one. A blackbody would have an emissivity of 1 and a perfect reflector would have a value of 0.
The emissivity of the surface of a material is its effectiveness in emitting energy as thermal radiation. Thermal radiation is light, but for objects near room temperature this light is infrared and isn't visible to human eyes. The thermal radiation from very hot objects (see photograph) is easily visible to the eye.uantitatively, emissivity is the ratio of the thermal radiation from a surface to the radiation from an ideal black surface at the same temperature as given by the StefanâBoltzmann law.