Important role of aromatic hydrocarbons in SOA formation from unburned gasoline vapor

A large-scale outdoor atmospheric simulation smog chamber for studying atmospheric photochemical processes: Characterization and preliminary application

“…A series of photochemical simulation experiments of hydrocarbons and NOx were designed and conducted according to the atmospheric conditions in Lanzhou and Beijing (Zhang and Li, 1998). Then a serious environmental issues were studied based on the smog chambers constructed with various size in the past decades, including the mechanism of photochemical reaction (Liu et al, 2017;Wang et al, 2014;Wu et al, 2007), ozone and SOA formation (Li et al, 2018a;Ma et al, 2018;Wang et al, 2015), biomass burning reactions (Zhang et al, 2011), the photochemical process of the gasoline and diesel (Chen et al, 2019a;Chen et al, 2019b;Kamens et al, 2011), physicochemical properties of SOA formed under various conditions (Li et al, 2017a;Li et al, 2020;Li et al, 2018b;Peng et al, 2018;Zhang et al, 2020), et al However, most of the chambers constructed in China were indoor smog chambers, establishment large-scale outdoor smog chambers in China was limited. In order to study the atmospheric pollution process close to China's actual atmospheric environment, it was necessary to build a large outdoor smog chamber in China.…”

A computationally efficient model to represent the chemistry, thermodynamics, and microphysics of secondary organic aerosols (simpleSOM): model development and application to α-pinene SOA

“…8,17 As lower-volatility products from multigenerational aging are produced later in the chamber experiment (except for products of autoxidation reactions 18 ), VBS-type parameters typically underestimate the formation of lower-volatility products. [19][20][21] Furthermore, when implemented in atmospheric models, multigenerational aging is either ignored or represented using generalized schemes that are not constrained to laboratory data. For instance, a commonly used gas-phase aging scheme 17 in atmospheric models only considers functionalization reactions despite evidence that fragmentation reactions become increasingly relevant with oxidation.…”

Secondary organic aerosol formation from mixed volatile organic compounds: Effect of RO2 chemistry and precursor concentration

“…In addition, our previous study also hinted that there may be synergistic effects among aromatic VOCs, considering that SOA formation from gasoline vapors increases non-linearly with increasing aromatic content 31 . The distinct differences in the oxidation degree of SOA formed at lower and higher VOC concentrations reported by our previous research suggested that the formation of gas-phase intermediates, especially products with low volatility, would change with changes in the initial precursor concentrations, then affecting the formation and composition of SOA from the photo-oxidation of aromatics 32 .…”

“…Considering the wall loss of gas-and particle-phase species on the Te on lm, all the gaseous species and SOA concentrations were (2.20 ± 0.39) × 10 − 4 min − 1 , respectively 31 . The deposition rate constant (k dep , h − 1 ) of an aerosol particle was determined to be related to its diameter (D p , nm) with a relationship of k dep = 4.15 × 10 − 7 × D p 1.89 + 1.39 × D p −0.88 using polydisperse ammonium sulfate (AS) aerosols, which have been widely used to correct aerosol wall loss in many previous studies 40,55,56 .…”