Perturbation Picture change effects

Upper canopy layer The dominant term in the upper canopy is the effect on the sink of the velocity perturbation through the last term of (5.27), r/2Lc [AuCB. Since Ail peaks at the hillcrest, this produces a minimum in Ac there. This effect can be interpreted as the canopy counterpart of the dominant role played by changes in surface stress on a rough hill in modulating the surface flux boundary condition, and thereby Ac, as discussed earlier. Hence, as a result of quite different dynamics, the dominant influences on Ac in the lower and upper canopy layers are in phase leading to a minimum in Ac at the hillcrest. This simple picture is modulated by other effects in the upper canopy layer, however. The eddy flux divergence couples the upper canopy to the shear stress layer above where advection is important at first order (5.26) and within which the contributions to Ac that are caused by canopy dynamics must decay to match the inviscid, streamline convergence effects around z = hi. 

From the bonding picture in Scheme 5 and from perturbation theory, one can predict that the homolytic bond strength will be proportional to the orbital overlap and inversely proportional to the energy difference 1E,-E2 between the two participating orbitals. The prediction of the effect of a variation of oxidation state on the homolytic bond strength is not an easy excercise. The reason is that a change of oxidation state will independently affect E,-E2 and the orbital overlap. 

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