Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Indoor transient SOA formation from ozone+α-pinene reactions: Impacts of air exchange and initial product concentrations, and comparison to limonene ozonolysis
Abstract The ozonolysis of reactive organic gases (ROG), e.g. terpenes, generates secondary organic aerosol (SOA) indoors. The SOA formation strength of such reactions is parameterized by the aerosol mass fraction (AMF), a.k.a. SOA yield, which is the mass ratio of generated SOA to oxidized ROG. AMFs vary in magnitude both among and for individual ROGs. Here, we quantified dynamic SOA formation from the ozonolysis of α-pinene with ‘transient AMFs,’ which describe SOA formation due to pulse emission of a ROG in an indoor space with air exchange, as is common when consumer products are intermittently used in ventilated buildings. We performed 19 experiments at low, moderate, and high (0.30, 0.52, and 0.94h−1, respectively) air exchange rates (AER) at varying concentrations of initial reactants. Transient AMFs as a function of peak SOA concentrations ranged from 0.071 to 0.25, and they tended to increase as the AER and product of the initial reactant concentrations increased. Compared to our similar research on limonene ozonolysis (Youssefi and Waring, 2014), for which formation strength was driven by secondary ozone reactions, the AER impact for α-pinene was opposite in direction and weaker, while the initial reactant product impact was in the same direction but stronger for α-pinene than for limonene. Linear fits of AMFs for α-pinene ozonolysis as a function of the AER and initial reactant concentrations are provided so that future indoor models can predict SOA formation strength.
Highlights We studied transient secondary organic aerosol (SOA) from α-pinene ozonolysis. Experiments had varying air exchange rates (AER) and initial concentrations. Transient aerosol mass fraction (AMF) parameters were fit to experimental data. Transient AMFs ranged from 0.071 to 0.25 at peak SOA concentrations. Transient AMFs increased with the AER and product of initial reactants.
Indoor transient SOA formation from ozone+α-pinene reactions: Impacts of air exchange and initial product concentrations, and comparison to limonene ozonolysis
Abstract The ozonolysis of reactive organic gases (ROG), e.g. terpenes, generates secondary organic aerosol (SOA) indoors. The SOA formation strength of such reactions is parameterized by the aerosol mass fraction (AMF), a.k.a. SOA yield, which is the mass ratio of generated SOA to oxidized ROG. AMFs vary in magnitude both among and for individual ROGs. Here, we quantified dynamic SOA formation from the ozonolysis of α-pinene with ‘transient AMFs,’ which describe SOA formation due to pulse emission of a ROG in an indoor space with air exchange, as is common when consumer products are intermittently used in ventilated buildings. We performed 19 experiments at low, moderate, and high (0.30, 0.52, and 0.94h−1, respectively) air exchange rates (AER) at varying concentrations of initial reactants. Transient AMFs as a function of peak SOA concentrations ranged from 0.071 to 0.25, and they tended to increase as the AER and product of the initial reactant concentrations increased. Compared to our similar research on limonene ozonolysis (Youssefi and Waring, 2014), for which formation strength was driven by secondary ozone reactions, the AER impact for α-pinene was opposite in direction and weaker, while the initial reactant product impact was in the same direction but stronger for α-pinene than for limonene. Linear fits of AMFs for α-pinene ozonolysis as a function of the AER and initial reactant concentrations are provided so that future indoor models can predict SOA formation strength.
Highlights We studied transient secondary organic aerosol (SOA) from α-pinene ozonolysis. Experiments had varying air exchange rates (AER) and initial concentrations. Transient aerosol mass fraction (AMF) parameters were fit to experimental data. Transient AMFs ranged from 0.071 to 0.25 at peak SOA concentrations. Transient AMFs increased with the AER and product of initial reactants.
Indoor transient SOA formation from ozone+α-pinene reactions: Impacts of air exchange and initial product concentrations, and comparison to limonene ozonolysis
Youssefi, Somayeh (Autor:in) / Waring, Michael S. (Autor:in)
Atmospheric Environment ; 112 ; 106-115
01.04.2015
10 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch