Search results for "Gaseous contaminants"
showing 2 items of 2 documents
Hydrogen sulfide measurements in air by passive/diffusive samplers and high-frequency analyzer: A critical comparison
2016
In this study, hydrogen sulfide (H2S) measurements in air carried out using (a) passive/diffusive samplers (Radiello® traps) and (b) a high-frequency (60 s) real-time analyzer (Thermo® 450i) were compared in order to evaluate advantages and limitations of the two techniques. Four different sites in urban environments (Florence, Italy) and two volcanic areas characterized by intense degassing of H2S-rich fluids (Campi Flegrei and Vulcano Island, Italy) were selected for such measurements. The concentrations of H2S generally varied over 5 orders of magnitude (from 101e103 mg/m3), the H2S values measured with the Radiello® traps (H2SR) being significantly higher than the average values measure…
A new approach for the measurement of gaseous elemental mercury (GEM) and H2S in air from anthropogenic and natural sources: Examples from Mt. Amiata…
2017
Real-time measurements of GEM and H2S discharged from natural and anthropogenic sources are a valuable tool to investigate the dispersion dynamics of these contaminants in air. In this study, a new approach to measure GEM and H2S concentrations in air, carried out by coupling a portable Zeeman atomic absorption spectrometer with high frequency modulation of light polarization (Lumex RA-915M) and a pulsed fluorescence gas analyzer (Thermo Scientific Model 450i), was applied to two distinct areas: (i) in the surroundings of Piancastagnaio (Siena, Central Italy), located in the eastern flanks of Mt. Amiata (a 200,000Â years old volcano), where three geothermal plants are operating and whose ex…