Relative erosion factor

Fie. 10 Relative erosion factors for selected commercially available metals at an impingement angle of 90°. Stellite 6B cobalt-base alloy was used as the reference material. Source Ref 5... 

The high bicarbonate yield in some of the Pacific Northwest streams could be the result of glacial action and mechanical erosion of rock material in basins having steep slopes that produce large amounts of relatively freshly fractured and fine-grained sediment that would participate readily in dissolution and alteration reactions. The rate at which such reactions would proceed is a function of net surface area of sediment available per unit volume of runoff and the length of time such material was exposed to water in the mnoff process. Therefore, the efficiency of solvent erosion under conditions in the Pacific Northwest region could be considerably increased by such factors. 

Re-epithelialization of comeal defects appears to depend in part upon the interaction of MMPs with matrix adhesion proteins on the exposed stromal surface to form the scaffolding for migrating basal epithelial cells (Fini et al 1996). Relative overexpression of MMPs may be a significant factor in refractory or indolent ulceration and in chronic superficial erosion in the horse. 

Further, the erosion law factor K, defined in equation (4), regulates the age distribution of eroded material relative to the age structure of the crust. Thus for a given crust mass v. time curve, the three parameters E, R and K fully describe the crust formation and erosion history. In the present modelling E was varied between 0.2 and 1, R from 0.3 to 0.7, and K from 1.5 to 3.5. The approach used and the effective partition coefficients, as well as initial (meteori-tic) concentrations of the trace species are the same as those used by Kramers Tolstikhin (1997) and Nagler Kramers (1998). 

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