emissivity

/em-uh-siv-i-tee, ee-muh-/US // ˌɛm əˈsɪv ɪ ti, ˈi mə- //UK // (ɪmɪˈsɪvɪtɪ, ˌɛm-) //

辐射率,发射率,放射性,发光率

Definitions

n.名词 noun

1
Thermodynamics.
- : the ability of a surface to emit radiant energy compared to that of a black body at the same temperature and with the same area.

Low-e, for “low emissivity,” refers to a microscopically thin coating of metallic particles that reflect some wavelengths of light while allowing most of the visible wavelengths to pass through.
Values which are commonly given for the surface emissivity must therefore be accepted with great reserve.
The emissivity increases with the temperature, else no state of thermal equilibrium could be reached.
Although these mantles emitted a brilliant light for a few hours, their light-emissivity was destroyed by carbonization.