the ratio of the amount of radiation by a surface to the amount of radiation incident upon it.
(physics) a measure of the ability of an object to absorb radiation, equal to the ratio of the absorbed radiant flux to the incident flux. For a layer of material the ratio of the flux absorbed between the entry and exit surfaces of the layer to the flux leaving the entry surface is the internal absorptance α Compare reflectance, transmittance
a photoelectric instrument for measuring the concentration of a substance, as a transparent solution, by its of monochromatic light.
absorptiometry absorptiometry (əb-sôrp’tē-ŏm’ĭ-trē) A method of chemical analysis in which a sample of a substance is exposed to electromagnetic radiation, and the amount of radiation absorbed by the sample is measured. This measurement is then used to determine the concentration or chemical composition of the substance. Absorptiometry is used in medicine to measure bone density.
the act of . the state or process of being . assimilation; incorporation: the absorption of small farms into one big one. uptake of substances by a tissue, as of nutrients through the wall of the intestine. a taking in or reception by molecular or chemical action, as of gases or liquids. Physics. the removal […]
- Absorption band
a dark band in the absorption spectrum of a substance, corresponding to a range of wavelengths for which the substance absorbs more strongly than at adjacent wavelengths. Historical Examples Where the curve is highest there the absorption band is thickest; where the curve is lowest there the band is weak. Poisons: Their Effects and Detection […]