photochemical_reaction has definitions from the field of chemistry
1
[ noun ] (chemistry) a chemical reaction produced by the action of light

Used in print

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

It would appear that it should be possible to determine unique mechanisms for the thermal and photochemical_reactions in both the liquid and gas phases and to determine values for activation_energies of some of the intermediate reactions of atoms and free_radicals , as_well_as information on the heat_of_dissociation of the carbon halogen bond .

The photochemical_reaction cells consisted_of 10 mm. i.d. Pyrex tubing , 5.5 cm. long , diffraction effects being minimized by the fact that the light passed_through only liquid glass interfaces and not gas glass interfaces .

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