Formation of In‐Cloud Aqueous‐Phase Secondary Organic Matter and Related Characteristic Molecules

Journal of Geophysical Research Atmospheres, Journal Year: 2024, Volume and Issue: 129(7)

Published: March 28, 2024

Abstract The formation process of in‐cloud aqueous‐phase secondary organic matter (aqSOM) and its characteristics are unclear. Herein, water‐soluble inorganic ions, oxalate, carbon (WSOC) were determined in cloud water aerosol (PM 2.5 ) samples simultaneously collected at a remote mountain site southern China during spring 2018 winter 2020. molecular compositions (WSOM) aerosols analyzed by Fourier transform ion cyclotron resonance mass spectrometer negative electrospray ionization (ESI‐) mode. results showed that the mean concentration WSOC was 6.27–8.54 mg C L −1 0.60–1.37 μg m −3 aerosols. strong correlation observed between WSOM aqueous (e.g., NO 3 − oxalate), positive matrix factorization results, elevated WSOM/K + ratios suggested enhanced aqSOM water. According to random forest analysis, factors related variation mainly included K , pH, atmospheric x . Additionally, 37 characteristic molecules, classified as ‐O ‐NO ‐N 2 O 1‐2 S, consisting dicarboxylic acids, nitrophenols, dinitrophenols, identified using linear discriminant analysis effect size (LefSe). N‐ S‐containing molecules with numbers >10 had low or extremely volatility; therefore, they might contribute after droplet evaporation. revealed modifying effects processes on composition level could improve our understanding aerosol–cloud interactions.

Language: Английский

Deciphering the Role of Microbial Extracellular and Intracellular Organic Matter in Antibiotic Photodissipation: Molecular and Fluorescent Profiling under Natural Radiation

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(26), P. 11661 - 11674

Published: June 14, 2024

This study addresses existing gaps in understanding the specific involvement of dissolved organic matter (DOM) fractions antibiotic photolysis, particularly under natural conditions and during DOM photobleaching. Employing fluorescent, chemical, molecular analysis techniques, it explores impact extracellular intracellular (EOM IOM) on photodissipation multiclass antibiotics, coupled with photobleaching solar radiation. Key findings underscore selective fractions, propelled by distinct chemical profiles, influencing DOM-mediated photolysis. Notably, lipid-like substances dominate IOM, while lignin-like prevail EOM, each uniquely responding to sunlight exhibiting Sunlight primarily targets fulvic acid-like lignin components contrasting initial changes observed tryptophan-like lipid IOM. The lower photolability attributed its rich unsaturated compounds, contributes an enhanced rate indirect photolysis (0.339-1.402 h

Language: Английский

Mild Diarylmethylation of Indoles through Regioselective 1,6-Hydroarylation of para-Quinone Methides in Microdroplets/Thin Film

ACS Sustainable Chemistry & Engineering, Journal Year: 2024, Volume and Issue: 12(25), P. 9522 - 9533

Published: June 13, 2024

Language: Английский