Photoreaction of Valerophenone
J. Phys. Chem. A, Vol. 102, No. 28, 1998 5723
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Figure 5. Half-lives computed for valerophenone photoreaction in
sunlight on clear days at latitude 40° N. The half-lives were computed
using a mathematical model24c that uses quantum yields, absorption
coefficients, and simulated solar spectral irradiance to compute pho-
tolysis rate constants.
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(3)
(4)
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∫
o,λ
λ
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t1/2 ) 0.693/kobs
where kobs is the pseudo-first-order rate constant for the
photoreaction; [V] the valerophenone concentration; Eo,λ the
scalar irradiance at wavelength λ; and j a unit conversion factor
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(Table 2).24c The computed seasonal changes for this actinom-
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valerophenone actinometer. Our computations using eq 3 and
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Acknowledgment. We thank G. Chapman for his assistance
with identification of the photoproducts using gas chromatog-
raphy/mass spectrometry. M.M.G., W.L.M., and H.G. thank TAI
Inc., the National Research Council, and the Oak Ridge Institute
for Science and Education (ORISE), respectively, for their
support.
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