THE FEASIBILITY OF UTILIZING CCSEM, CLUSTER ANALYSIS AND FRACTAL ANALYSIS TECHNIQUES TO CHARACTERIZE AND EVALUATE ATMOSPHERIC AEROSOLS

THE SCANNING ELECTRON MICROSCOPE (SEM) COMBINED WITH AN ENERGY DISPERSIVE X-RAY ANALYZER (EDX) IS IDEAL FOR CHARACTERIZING THE SIZE, COMPOSITION, AND MORPHOLOGY OF PARTICULATE MATTER. THIS TECHNOLOGY IS OFTEN LIMITED, HOWEVER, BY THE INABILITY TO COLLECT DATA ON STATISTICALLY SIGNIFICANT PARTICLE POPULATIONS. AS A RESULT, MUCH OF THE MICROSCOPIC WORK PERFORMED TO DATE HAS BEEN QUALITATIVE RATHER THAN QUANTITATIVE. HOWEVER, RECENT ADVANCES IN COMPUTER CONTROL AND DATA PROCESSING TECHNIQUES ARE RAPIDLY CHANGING THE VERY NATURE OF MICROSCOPIC ANALYSES. TODAY, COMPUTER CONTROLLED SCANNING ELECTRON MICROSCOPY (CCSEM) AND AUTOMATIC IMAGE ANALYSIS PERMIT QUANTIFICATION OF ATMOSPHERIC AEROSOLS AND SUBTLE DIFFERENCES IN THE SIZE, SHAPE, AND COMPOSITION OF ATMOSPHERIC AEROSOLS. COUPLING THIS RAPIDLY EMERGING TECHNOLOGY WITH CLUSTER ANALYSIS, A MATHEMATICAL TECHNIQUE FOR IDENTIFYING COMMONALITY IN OBJECTS OR GROUPS OF OBJECTS, AND FRACTAL ANALYSIS, A MATHEMATICAL TECHNIQUE WHICH PERMITS DETAILED QUANTIFICATION OF SURFACE TEXTURE COMPARABLE TO THE DETAIL PERCEIVED BY THE HUMAN EYE, SHOULD PERMIT QUANTIFICATION OF PARTICULATE MATTER IN A MANNER NEVER BEFORE PERFORMED. THIS PROPOSED PROJECT INTENDS TO DEMONSTRATE THE FEASIBILITY OF USING A NOVEL COMBINATION OF CCSEM, CLUSTER ANALYSIS AND FRACTAL ANALYSIS TECHNIQUES TO CHARACTERIZE ATMOSPHERIC AEROSOLS.