7
0
D. Vione et al. / Journal of Photochemistry and Photobiology A: Chemistry 224 (2011) 68–70
range, from 1 to 1010 (M−1
s
−1 −1
or s as applicable), and a con-
Acknowledgements
ventional value of 107 was adopted. The value of k17 is probably
some orders of magnitude lower [14], but a modification would not
change the calculation results. From the equilibrium reaction (8) it
Financial support by PNRA-Progetto Antartide and by MIUR-
PRIN2009 (project 20092C7KRC-ARCTICA) is gratefully acknowl-
edged. The bursary of BS in Torino was supported by Compagnia di
San Paolo, Torino, Italy.
•
−2
−•
was derived [HO2 ] = 6.3 × 10
[O2 ] at pH 6, and reaction (9)
was modified accordingly. The CKS results are independent of the
actual values adopted for k , k and k , they rather depend on their
2
3
4
10
−1 −1
M s
ratios. Anyway, it was hypothesised k = 10
. Fig. 2 shows
Appendix A. Supplementary data
4
the comparison between experimental data and model results for
−
1
2
−1
−1
: 3 (a), 5 (b)
3
k × k
= 10 M
and different values of k × k
Supplementary data associated with this article can be found, in
the online version, at doi:10.1016/j.jphotochem.2011.09.008.
4
3
2
and 7 (c). No good agreement with the experimental data can
−1
−1
3
be obtained for k × k
outside the 3–7 range, or for k × k
2
3
4
2
−1
values that are significantly different from 10 M . This means
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−
•
•
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2
[
−
•
•
2
2
the supplementary material) that would enhance nitration.