action spectrum


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Fig. 9 Action spectrum . The absorption and action spectra of chlorophyll.

action spectrum

a range of wavelengths of light within which a physiological process can take place. For example, the range of wavelengths of light in which the chlorophyll in green plants is able to synthesize carbohydrates by photosynthesis corresponds closely to the ABSORPTION SPECTRUM, showing that most of the light absorbed by chlorophyll is actually used in photosynthesis. See Fig. 9 .
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This is [E.sub.MS] (1,[theta]) where i=l,2, ..., labels individual data points expressed in W [m.sup.-2] with the normalized action spectrum implicit in the reported values.
Action spectrum conversion factors that change erythemally weighted to previtamin [D.sub.3] -weighted UV doses.
(1972) Significance of Enhancement for Calculations Based on the Action Spectrum for Photosynthesis.
An action spectrum for melatonin suppression: evidence for a novel non-rod, non-cone photoreceptor system in humans.
In the following, we discuss common sources of error in UV radiation measurements, including out-of-band contributions to the signal, non-ideal geometric properties (non-ideal cosine response in the meters), and poor matching to a defined action spectrum.
Moreover, the researchers found that the absorption spectrum of the smallest particles matched the action spectrum of unsorted eumelanin.
Because knowledge about the action spectrum for the induction of melanoma is limited, a risk analysis for this condition could not be conducted.
As a guide in debugging your typing, here are some values that the program should return at a wavelength of 3000 angstroms: ozone transmission 0.0376, air transmission 0.1903, and action spectrum 0.65.
The first idea is to commercialize solid-state light engines, which can be directed to contain the proper circadian action spectrum when used during the day, and to remove these shorter wavelengths at night.
Photopic detectors have a wide bandwidth and spectral response that closely follows the CIE photopic action spectrum. Near-UV irradiance is then measured by an independent UVA light detector.
The mechanism of skin injury has been closely co-related to the phenomenon that the action spectrum for UVB erythema has been found to be close to the absorption spectrum for DNA after adjusting for the absorbance of incident energy by the stratum corneum.

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