Acidic Deposition: State of Science and Technology. Report 20. Processes of Deposition to Structures

摘要

The prediction of service lives of materials under a range of exposure conditions is central to the question of quantifying acidic deposition-induced damages to materials. In order to estimate reduction in service lives, it is necessary to understand the chemical interaction between the atmosphere and the materials, the physics of the pollutant delivery or deposition processes, and the structural consequences of enhanced deterioration from exposure to acidic deposition. In conjunction with specific data on the types and distribution of materials and the types of distributions of deposited pollutants over the geographical area of interest, estimates of service lives can be made. The purpose of the report is to present current understanding of the physical processes influencing deposition of atmospheric contaminants (gases, particles, and in precipitation) in urban areas and to the material surfaces found therein.