Gas-Phase Nitrate Radical Production Using Irradiated Ceric Ammonium Nitrate: Insights into Secondary Organic Aerosol Formation from Biogenic and Biomass Burning Precursors DOI
Andrew T. Lambe, Chase K. Glenn, Anita M. Avery

et al.

ACS Earth and Space Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 19, 2025

The importance of nitrate radicals (NO3) as an atmospheric oxidant is well-established. For decades, laboratory studies multiphase NO3 chemistry have used the same methods – either NO2 + O3 reactions or N2O5 thermal decomposition to generate it occurs in atmosphere. These methods, however, come with limitations, especially for N2O5, which must be produced and stored under cold dry conditions until its use. Recently, we developed a new photolytic source gas-phase by irradiating aqueous solutions ceric ammonium nitric acid. In this study, adapted method maintain stable concentrations over 24 h. We applied oxidation flow reactor (OFR) experiments measure yield chemical composition oxygenated volatile organic compounds (OVOCs) secondary aerosol (SOA) formed from (VOCs) emitted biogenic sources (isoprene, β-pinene, limonene, β-caryophyllene) biomass burning (phenol, guaiacol, syringol). SOA yields elemental ratios were typically within factor 2 10%, respectively, those obtained using conventional sources. Maximum our ranged 0.02 (isoprene/NO3) 0.96 (β-caryophyllene/NO3). highest oxygen-to-carbon (O/C) 0.48 (β-caryophyllene/NO3) 1.61 (syringol/NO3). Additionally, characterized novel condensed-phase products syringol/NO3 reactions. Overall, use irradiated cerium may enable more widespread NO3-initiated oxidative aging, has been less explored compared that hydroxyl radical chemistry.

Language: Английский

Rapid Nighttime Darkening of Biomass Burning Brown Carbon by Nitrate Radicals Is Suppressed by Prior Daytime Photochemical Aging DOI
Carolyn Liu-Kang, Laura-Hélèna Rivellini, Xinke Wang

et al.

ACS Earth and Space Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 12, 2025

Language: Английский

Citations

0
Key Roles of Bulk Viscosity and Acidity on Liquid–Liquid Phase Separation of Atmospheric Organic–Inorganic Mixed Aerosols DOI

Yuanyuan Ye,

Jingyu Sun,

Younuo Fan

et al.

The Journal of Physical Chemistry A, Journal Year: 2025, Volume and Issue: unknown

Published: April 22, 2025

Liquid-liquid phase separation (LLPS) and the resulting particle morphologies in atmospheric organic-inorganic mixed aerosols are key regulators of aerosol chemistry climate forcing. However, influence coexisting viscous water-soluble organic compounds (WSOCs) on LLPS behavior complex multicomponent systems remains poorly understood. In this study, we introduced three representative WSOCs, i.e., sucrose (SUC), glycerol (GLY), citric acid (CA), to increase bulk viscosity a model system composed 1,2,6-hexanetriol (HXT) ammonium sulfate (AS). Using microscopic imaging techniques predictions, examined impact mass transfer limitations LLPS. As WSOC fractions increased, both relative humidity (SRH) efflorescence (ERH) progressively decreased. For HXT/AS/SUC HXT/AS/CA with molar ratios 1:1:0.5 1:1:0.75, was completely suppressed, although still occurred. 1:1:1 mixtures, neither nor observed. contrast, addition GLY caused minimal changes transitions due its minor effect aqueous-phase viscosity. Additionally, reducing acidity, along transformation CA into salts, alleviated molecular transport limitations, leading increased SRH ERH values for mixtures. These findings critical advancing high-resolution state modeling assessing implications presence or absence

Language: Английский

Citations

0
Gas-Phase Nitrate Radical Production Using Irradiated Ceric Ammonium Nitrate: Insights into Secondary Organic Aerosol Formation from Biogenic and Biomass Burning Precursors DOI
Andrew T. Lambe, Chase K. Glenn, Anita M. Avery

et al.

ACS Earth and Space Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 19, 2025

The importance of nitrate radicals (NO3) as an atmospheric oxidant is well-established. For decades, laboratory studies multiphase NO3 chemistry have used the same methods – either NO2 + O3 reactions or N2O5 thermal decomposition to generate it occurs in atmosphere. These methods, however, come with limitations, especially for N2O5, which must be produced and stored under cold dry conditions until its use. Recently, we developed a new photolytic source gas-phase by irradiating aqueous solutions ceric ammonium nitric acid. In this study, adapted method maintain stable concentrations over 24 h. We applied oxidation flow reactor (OFR) experiments measure yield chemical composition oxygenated volatile organic compounds (OVOCs) secondary aerosol (SOA) formed from (VOCs) emitted biogenic sources (isoprene, β-pinene, limonene, β-caryophyllene) biomass burning (phenol, guaiacol, syringol). SOA yields elemental ratios were typically within factor 2 10%, respectively, those obtained using conventional sources. Maximum our ranged 0.02 (isoprene/NO3) 0.96 (β-caryophyllene/NO3). highest oxygen-to-carbon (O/C) 0.48 (β-caryophyllene/NO3) 1.61 (syringol/NO3). Additionally, characterized novel condensed-phase products syringol/NO3 reactions. Overall, use irradiated cerium may enable more widespread NO3-initiated oxidative aging, has been less explored compared that hydroxyl radical chemistry.

Language: Английский

Citations

0