Copper patinas formed in the atmosphere—III. A semi-quantitative assessment of rates and constraints in the greater New York metropolitan area

摘要: Because of the ability copper to interact with a variety atmospheric species and retain signatures those interactions in stable patina layer, is particularly appropriate material for study rates corrosion processes. The rate formation patinas specific geographical location dependent upon concentrations corrosive species, their degree interaction surface, mechanisms processes that govern interaction. A semi-quantitative model growth developed samples exposed up several decades atmosphere greater New York City metropolitan area. In contrast previous studies chemistry, which have dealt equilibrium conditions, present work treats problem from kinetic standpoint. Under modern circumstances, it shown neither supply water, incorporated atmosphere, nor oxidation chemistry are limiting factors growth. Rather, controlled by cementation components at early stages process diffusing ions later stages. To assess on historical basis, estimates made precipitation area over past century. rapid patinas, compared formed few ago, be consequence increased levels strong inorganic acids, H2SO4, perhaps combination oxidizing organic compounds.