Master of Science (MS), Bowling Green State University, 2020, Geology

The purpose of this study is determining a potential correlation between soil moisture and burn severity as well as examining potential correlations between slope, elevation, wind speed, wind direction and Normalized Difference Vegetation Index (NDVI) value and burn severity within the Mendocino Complex Fire, California, which occurred in 2018. A time-series of the difference Normalized Burn Ratio (dNBR), the difference between pre- and intra-fire NBR values, was calculated via Sentinel-2, soil moisture was mapped using SMAP, and the Digital Elevation Model (DEM) from ASTER was used to derive elevation and slope values. The imagery was obtained from USGS and USDA websites. Images were processed and reprojected to the same spatial resolution (60 m) and projection (UTM Zone 10N, WGS-87). dNBR imagery was subdivided in newly burned areas for each consecutive day for ten days from 29 July 2018 to 31 August 2018. The findings suggested that there was no strong correlation trend consistently found over the proposed period of time between dNBR values and soil moisture content (R ≈ -0.20 to 0.39), slope (R ≈ -0.35 to 0.46), elevation (R ≈ -0.24 to 0.56), wind speed (R ≈ -0.15 to 0.36), and wind direction (R ≈ -0.42 to 0.24). However, a positive correlation between NDVI values and dNBR values was found to be strong and consistent (R ≈ -0.48 to 0.57). This implies that burn severity increased more significantly and frequently with NDVI, a surrogate for vegetation biomass and leaf area index. It can be surmised that soil moisture must reach some higher values before having a possible impact upon burn severity. Considering that the summer of 2018 was one of the warmest and driest summers in the study area's recent history, soil moisture content was relatively low while, simultaneously, vegetation was dry and more prone to burning.

Committee: Anita Simic Milas Ph.D. (Advisor); Yuning Fu Ph.D. (Committee Member); Ganming Liu Ph.D. (Committee Member) Subjects: Environmental Geology; Geography; Geology; Remote Sensing; Statistics

Master of Science in Polymer Engineering, University of Akron, 2005, Polymer Engineering

Addition of organophilic layered silicates (montmorillonite) to the polymer matrix produces effective polymer nanocomposites by intercalation of macromolecules into the interlayer spaces. Rubber nanocomposites represent an untapped application that is still in an early stage of development. This research work focuses broadly on the property enhancement of rubber matrices through the incorporation of different types of layered silicates and a dispersion agent, Hexamethoxymethylmelamine (HMMM), to the composite formulation. Styrene butadiene rubber (SBR) and acrylonitrile butadiene rubber (NBR) rubber nanocomposites were prepared using the commercially viable rubber compounding process and investigated through wide angle x-ray diffraction to determine the resulting clay morphology. The mechanical evaluation of the rubber nanocomposites was performed by tensile and tear testing. The effect of the dispersing agent was manifested in both the morphology and mechanical properties, which showed significant increase when added to the right combination of the modified organoclay and rubber type due to an increase d-spacing distance in the gallery height shown through WAXD. This work thus proves the positive benefit of such dispersion agents.

Committee: Lloyd Goettler (Advisor) Subjects: Chemistry, Polymer