PAH and N-PAH were determined by using a Trace GC gas chromatograph coupled with a Trace Q mass spectrometer. For PAH and N-PAH, the detector was operated in the selected ion monitoring (sim) modality. The instrument was purchased from Thermo, Rodano MI, Italy. Separations of analyses were obtained through a 25-m-long, RT5MS-type (methylphenyl silicone stationary phase; i.d. = 250 ^m, film = 0.33 p.m) capillary column provided by Superchrom, Milan, Italy. The mass spectrometer system was operated in electron impact mode (ion source energy = 70 eV) and GC/MS data were acquired by a dedicated software (Excalibur) purchased from Thermo. n-Alkanes were processed through a second Trace GC system equipped with a similar GC column combined to a flame ionization detector.

Compounds identification was based upon comparison of eluted peaks with authentic analyze standards, GC retention times, mass spectra derived from reference (NIST) as well as home-made libraries and interpretation of mass spectrometric fragmentation patterns. Quantification of the compounds was conducted by comparing GC peak areas with those of known co-injected standards (internal standard method), after checking for the concentrations lied within the detector operative ranges (usually 3-1000 times the respective detection limits). Filter blanks, occurring only for some semivolatile n-alkanes (up to C18), phenanthrene and pyrene among PAH, were subtracted to obtain neat aerial concentrations of compounds. Analytical uncertainty in any case did not exceed 15%.

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Renewable Energy Eco Friendly

Renewable Energy Eco Friendly

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable.

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