摘要
Single particle characterization can provide information on the evolution of size distribution and chemical composition of pollution aerosol. The work described the use of Scanning Electron Microscopy (SEM) combined with X-ray Dispersive Energy Spectrometry (EDS) to characterize inorganic atmospheric particles samples collected on PM10 filters from January 2013 to October 2013 from three zones within the city of Hermosillo, Sonora. Specimens were initially processed by separating the collected particles from the filters by means of submersing a 2 cm2 section of each filter into isopropilic alcohol within a test tube for 5 minutes. Then, an aliquot of the suspension was placed over a sample holder and into the SEM. The different elements found amongst individual particles were Al, Ba, Ca, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Pb, S, Si, Ti and U. The predominant elements are Al (17.10 At%), Si (10.17 At%), Ba (5.90 At%), Fe (5.45 At%) and U (2.32 At%). The particles were classified into groups based on morphology and elemental composition: particles of aluminosilicate, salts of sodium chloride, sulfates, metal particles, barium and uranium. These particles morphology and chemical composition, illustrate an abundance of natural elements within the zone. However, some of the elements presented are directly related with human activities, and are of much interest from the public health and environmental perspectives.
Single particle characterization can provide information on the evolution of size distribution and chemical composition of pollution aerosol. The work described the use of Scanning Electron Microscopy (SEM) combined with X-ray Dispersive Energy Spectrometry (EDS) to characterize inorganic atmospheric particles samples collected on PM10 filters from January 2013 to October 2013 from three zones within the city of Hermosillo, Sonora. Specimens were initially processed by separating the collected particles from the filters by means of submersing a 2 cm2 section of each filter into isopropilic alcohol within a test tube for 5 minutes. Then, an aliquot of the suspension was placed over a sample holder and into the SEM. The different elements found amongst individual particles were Al, Ba, Ca, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Pb, S, Si, Ti and U. The predominant elements are Al (17.10 At%), Si (10.17 At%), Ba (5.90 At%), Fe (5.45 At%) and U (2.32 At%). The particles were classified into groups based on morphology and elemental composition: particles of aluminosilicate, salts of sodium chloride, sulfates, metal particles, barium and uranium. These particles morphology and chemical composition, illustrate an abundance of natural elements within the zone. However, some of the elements presented are directly related with human activities, and are of much interest from the public health and environmental perspectives.
