absorbance

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absorbance

 [ab-sor´bans]
in radiology, a measure of the ability of a medium to absorb radiation, expressed as the logarithm of the quotient of the intensity of the radiation entering the medium divided by that leaving it.

ab·sor·bance (A, A),

(ab-sōr'bants),
spectrophotometry log of the ratio of the radiant power of the incident radiation to the radiant power of the transmitted radiation.

absorbance

/ab·sor·bance/ (-sor´bans)
1. in analytical chemistry, a measure of the light that a solution does not transmit compared to a pure solution. Symbol .
2. in radiology, a measure of the ability of a medium to absorb radiation, expressed as the logarithm of the ratio of the intensity of the radiation entering the medium to that leaving it.

absorbance

[əbsôr′bəns]
the degree of absorption of light or other radiant energy by a medium exposed to the energy. It is expressed as the logarithm of the ratio of energy transmitted through a vacuum to the energy transmitted through the medium. For solutions, it is the logarithm of the ratio of energy transmitted through pure solvent to the energy transmitted through the solution. Absorbance varies with factors such as wavelength, solution concentration, and path length.

Absorbance

Chemistry A logarithm of the percent transmission of a wavelength of light through a liquid. 
Microbiology A measure of the amount of light absorbed by a suspension of bacteria or an organic solution, measured by spectrophotometry. Absorbance values are used to plot the growth of bacteria in broth and gauge the purity and concentration of molecules in solution.

ab·sor·bance

(ăb-sōr'băns)
spectrophotometry 2 minus the log of the percentage transmittance of light.
Synonym(s): extinction (2) , optic density.

absorbance

a spectrophotometric measurement of the light absorbed by a solution at a particular WAVELENGTH. The absorbance (A) derives from the percentage of light transmitted as follows:

where Io is the incident light intensity and I is the transmitted light intensity. The absorbance is related to the molar absorption coefficient (extinction coefficient) e (cm-1M-1), concentration c (M), and path length l (cm) as follows:

Absorbance can therefore be used to determine the concentration of a substance in solution, to follow conversion of a SUBSTRATE to a product in an enzymic reaction (see ENZYME), and so on.

Absorbance is sometimes referred to as OPTICAL DENSITY, although this term should be used for measurement of light scattering.

absorbance 

A measure of absorption equal to the logarithm to the base 10 of the reciprocal of the transmittance T, for a specified wavelength and expressed as A = −log10 T. Syn. optical density. See optical density; transmittance.

absorbance

in radiology, a measure of the ability of a medium to absorb radiation, expressed as the logarithm of the quotient of the intensity of the radiation entering the medium divided by that leaving it.
References in periodicals archive ?
To a first approximation, photon absorption follows the Lambert-Beer law, where the number of photons present at depth l is related to the optical absorbancy.
The court found that the absorbancy of the material handed to the plaintiff to dry his foot would not be "beyond the common sense, experience, and education of the average juror.
absorbancy of the extract revealed that the maximum absorbance of the CLJ extract was approximately at 215-225 nm, which is the range of absorbance of peptide bonds carbonyl groups.
One of the benefits of this composite over other wood products is that it offers better anti-slipperiness under wet or dry conditions and has very low moisture absorbancy," he adds.
We measured NADPH-P450 reductase activity in postmitochondrial fractions of purified interstitial cells as the change in absorbancy at 550 nm (28).
First, a standard curve relating the number of colonies in a sample and that sample's light absorbancy rate was developed.