Chemical determination of organic aerosols was performed by applying a procedure described extensively elsewhere (Yassaa et al., 2005). Briefly, samples were spiked with a solution of perdeuterated species adopted as internal reference compounds. Then, the organic content was extracted by refluxing aerosol-enriched filters in soxhlet, using a dichloromethane-acetone (4:1) mixture for 16 hours. The extract was evaporated and the residue was divided into two ali-quots. Most of the extract (4/5 of the total) was fractionated through a column chromatography on neutral alumina (2 g, partly deactivated with 2.5% ww of water). Non-polar aliphatic compounds were first eluted with iso-octane (6 mL), while the bulk of medium-polar organics were collected by passing dichloro-methane-iso-octane (3:2, 6 mL) through the column; this fraction comprised PAH, N-PAH; polar species were eluted with a third solvent, i.e., acetone (6 mL). All sample fractions were stored in the dark at low temperature (4°C) until the analysis.
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Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.