actinometer has definitions from the field of physics
1
[ noun ] (physics) an instrument for measuring the intensity of electromagnetic radiation (usually by the photochemical effect)

Used in print

(Francis J. Johnston and John E. Willard, "The...)

It was possible to make estimates of the quantum yield by observing the extent of reduction of a uranyl_oxalate actinometer solution illuminated for a known time in a typical reaction cell and making appropriate conversions based on the differences in the absorption_spectra of uranyl_oxalate and of chlorine , and considering the spectral distribution of the light source .

Related terms

measuring_instrument

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