放ほう射しゃ率りつ

noun

emissivity

Physics term: the ratio of radiation emitted by a surface to that emitted by a blackbody at the same temperature.

• この材ざい料りょうの放ほう射しゃ率りつは0.9以い上じょうです。

  The emissivity of this material is 0.9 or higher.