Morphological studies of model and native environmental surface films

The body of work in this dissertation focuses on the properties of an environmental thin film system, including the roughness and composition of the surface. The deposition of particles, such as airborne soil and plant pollen, from the atmosphere creates a thin film known as “environmental film” or “urban film” that covers virtually all of Earth’s solid surfaces. Environmental films have been shown to accumulate a variety of chemicals, including toxic pollutants. To investigate the means by which environmental films uptake chemicals, model films are made in the lab and real films are collected outside. Model films serve to mimic the properties of native films and allow for a simple analysis of a complex system. Native films serve to provide real field samples to analyze. The properties of model and native films are characterized using reflected light to determine what the film is made of and microscopes capable of imaging small particles. The results of the model film study indicate a model capable of reproducing the surface roughness and other properties of native films. This study serves as a platform with the goal of making model films that better mimic native films. The results of the native film study indicate successful imaging using microscopes capable of revealing the structure and chemical composition of the films. This imaging adds an important contribution to the field that has not previously been performed.