Oligomer and highly oxygenated organic molecule formation from oxidation of oxygenated monoterpenes emitted by California sage plants

Abstract

Abstract. Plants emit a diverse range of biogenic volatile organic compounds (BVOCs) whose oxidation leads to secondary organic aerosol (SOA) formation. The majority of studies of biogenic SOA have focused on single or simple multicomponent BVOC mixtures thought to be representative of Northern hemispheric deciduous or mixed forest conditions. Gaps remain in our understanding of SOA formation from complex mixtures of real plant emissions in other environments. Towards the goal of understanding SOA in other regions, we conducted the first comprehensive study of SOA from oxygenated monoterpenes. These are the dominant emissions from the most common plant species in southern California's coastal sage ecosystem: black sage (Salvia mellifera) and California sagebrush (Artemisia californica). Emissions from sage plants, as well as single compounds representing their major emissions (camphor, camphene and eucalyptol), were oxidised in an Aerodyne potential aerosol mass oxidation flow reactor (PAM-OFR). The chemical composition of SOA was characterised using a high-resolution time-of-flight iodide-anion chemical-ionisation mass spectrometer equipped with a Filter Inlet for Gases and AEROsols (FIGAERO-I-HR-ToF-CIMS) under low- and medium-NOx conditions. SOA from oxygenated monoterpenes showed a higher-order oligomer content and a greater presence of highly oxygenated organic molecules (HOMs) than non-oxygenated monoterpenes, with HOM contributing 27 %–47 % and 12 %–14 % of SOA product signal from oxygenated and non-oxygenated monoterpenes respectively. This study highlights the potential importance of oxygenated monoterpene emissions for SOA formation in woody shrub ecosystems.

Inorganic Ions Enhance the Number of Product Compounds through Heterogeneous Processing of Gaseous NO2 on an Aqueous Layer of Acetosyringone

“…The detected products are all highly oxygenated compounds with a molecular mass that is often higher than that of ACS, which can have implications for SOA formation processes. Indeed, it has been shown that highly oxygenated compounds in the gas phase contribute to the formation of SOA, in particular, by participating in the growth of new particles. , …”

Influence of Fuel Properties on the Light Absorption of Fresh and Laboratory-Aged Atmospheric Brown Carbon Produced from Realistic Combustion of Boreal Peat and Spruce Foliage

“…This explanation matches our finding that the contribution of the LMW fraction to total BrC absorption is lower at higher peat moisture contents (Figure c). Lower combustion temperatures are also associated with decreased emission of highly oxygenated species, which are important for the secondary formation of high-molecular-weight (HMW) species; ,, this could also account for the smaller absorption contributions from LMW chromophores at higher peat moisture contents.…”

Real-Time Measurements of Botanical Disinfectant Emissions, Transformations, and Multiphase Inhalation Exposures in Buildings

“…While SOA production due to monoterpene ozonolysis has been well studied, ,,− comparatively less is known with regard to monoterpenoid ozonolysis. A few studies have observed SOA production due to the ozonolysis of C 10 H 16 O and C 10 H 18 O isomers, ,− while C 10 H 14 O and C 10 H 20 O isomers have not yet been evaluated. In addition to HOMs produced by the ozonolysis of monoterpenes and monoterpenoids, it is likely that human-emitted ammonia (NH 3 ) , (via the researcher applying the disinfectant) and outdoor-to-indoor transported sulfuric acid (H 2 SO 4 ) − (via the powered ventilator) participated in the initial steps of particle nucleation and growth.…”