Unexpected molecular diversity of brown carbon formed by Maillard-like reactions in aqueous aerosols

Abstract

We found unexpected molecular diversity of brown carbon formed by Maillard-like reactions in aqueous aerosols, and carbonyl precursors play a more important role in determining the molecular diversity of brown carbon.

Unsaturated Fatty Acids Enhance Aqueous Atmospheric Oxidation Ability by Producing Oxygen‐Containing Radicals in Fog Droplets

“…Figures S1 and S2 in Supporting Information showed time‐dependent absorption spectra of two groups and Figures S3 and S4 in Supporting Information showed absorption index time profiles and kinetics recorded during the reaction of Gly + GX, Ala + GX, Gly/Ala + GX, Gly + MG, Ala + MG, and Gly/Ala + MG. The related experimental results demonstrated organic amines can form BrC with carbonyl compounds in the liquid phase (Tang et al., 2022). Powelson et al.…”

“…Figures S1 and S2 in Supporting Information S1 showed time-dependent absorption spectra of two groups and Figures S3 and S4 in Supporting Information S1 showed absorption index time profiles and kinetics recorded during the reaction of Gly + GX, Ala + GX, Gly/Ala + GX, Gly + MG, Ala + MG, and Gly/Ala + MG. The related experimental results demonstrated organic amines can form BrC with carbonyl compounds in the liquid phase (Tang et al, 2022). Powelson et al (2014) reported significantly faster reactions for MG versus GX with bulk phase reactions at pH 4 and the same initial reactants concentrations of 0.05-0.25 M. However, according to the data in Table 1, the reaction rate with GX was higher than that with MG when the bulk reaction was performed at pH 4.9 and different ratios of reactant concentrations.…”

“…Maillard‐like reaction between carbonyl and amino compounds is one of the main ways to form BrC in the liquid phase (Yi et al., 2018). In atmospheric samples, about 35%–64% of molecular formulas were detected in simulated Maillard reaction products (Tang et al., 2022). Liquid phase reaction is regarded as an important pathway to form organic aerosols and has become a research hotspot (Song et al., 2013).…”

Molecular-Weight-Dependent Infiltration and Adsorption of Polymers into Nanochannels

“…Several PS/cyclohexane solutions of known concentration were prepared and measured to create the calibration curve. The absorption band centered around 260 nm originates from the benzene ring of PS . The intensity of the absorption band increases with increasing polymer concentration (Figure S12a).…”

Heterogeneous chemistry of methyl ethyl ketone on mineral oxide surfaces: impacts of relative humidity and nitrogen dioxide on product formation

“…6,9,11,12 Furthermore, some carbonyl compounds such as glyoxal are precursors for Brown Carbon (BrC) formation. [13][14][15][16][17] Despite the abundance of carbonyl compounds in the atmosphere, for the most part, heterogeneous and multiphase reactions of these compounds on mineral surfaces were considered insignicant due to their volatility. 12 MEK is the second most abundant atmospheric carbonyl compound aer acetone, 11,18 with a typical mixing ratio of 0.03-4 ppb.…”