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 w...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.展开更多
In the present study, the air quality is assessed for the year 2010 regarding to the Total Suspended Particles (TSP) for six cities of Sonora, Mexico, representing the first regional study in Sonora in air quality. Th...In the present study, the air quality is assessed for the year 2010 regarding to the Total Suspended Particles (TSP) for six cities of Sonora, Mexico, representing the first regional study in Sonora in air quality. The assessment used performance indicators and indicators of compliance with the regulations. It is established that in all the cities the maximum limit value of daily concentration of 210 μg/m3 is exceeded, being the percentage of days above the rule of 30%, 78%, 76%, 6%, 3% and 62% for Agua Prieta, Nogales, Puerto Penasco, Hermosillo, Guaymas and Obregón respectively, classifying these days with poor air quality. According to the annualized index used, the air quality was not satisfactory for the period of study in the six cities. Nogales and Puerto Penasco presented the most adverse conditions of air quality with annual average values of TSP of 363 and 345 μg/m3 and maximum daily of 1047 and 1239 μg/m3 (498% and 590% above the norm) respectively. The requirements of coverage that establishes the Mexican Official Standard NOM-025-SSA1-1993 (SSA, 2005) are questioned for its compliance, proposing in this paper a criterion of non-compliance by prioritizing the protection of health and the precautionary principle. It is recommended to implement air quality management programs (PROAIRE) in these cities.展开更多
文摘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.
基金supported by the Institute of Engineering of the Autonomous University of Baja California,also by to the Industrial Environmental Engineering Program of the Sonora State University,and the Division of Engineering,Department of Chemical Engineering and Metallurgy of the University of Sonora.
文摘In the present study, the air quality is assessed for the year 2010 regarding to the Total Suspended Particles (TSP) for six cities of Sonora, Mexico, representing the first regional study in Sonora in air quality. The assessment used performance indicators and indicators of compliance with the regulations. It is established that in all the cities the maximum limit value of daily concentration of 210 μg/m3 is exceeded, being the percentage of days above the rule of 30%, 78%, 76%, 6%, 3% and 62% for Agua Prieta, Nogales, Puerto Penasco, Hermosillo, Guaymas and Obregón respectively, classifying these days with poor air quality. According to the annualized index used, the air quality was not satisfactory for the period of study in the six cities. Nogales and Puerto Penasco presented the most adverse conditions of air quality with annual average values of TSP of 363 and 345 μg/m3 and maximum daily of 1047 and 1239 μg/m3 (498% and 590% above the norm) respectively. The requirements of coverage that establishes the Mexican Official Standard NOM-025-SSA1-1993 (SSA, 2005) are questioned for its compliance, proposing in this paper a criterion of non-compliance by prioritizing the protection of health and the precautionary principle. It is recommended to implement air quality management programs (PROAIRE) in these cities.
