Chemical Research in Chinese Universities, Год журнала: 2024, Номер unknown
Опубликована: Июль 12, 2024
Язык: Английский
Environmental Science Atmospheres, Год журнала: 2025, Номер unknown
Опубликована: Янв. 1, 2025
Photodegradation alters secondary organic aerosol (SOA) chemical composition and physical properties, promoting the formation of oxidation products in both gas- particle-phase by depleting high-molecular-weights species within SOA.
Язык: Английский
Процитировано
0
Environmental Science & Technology, Год журнала: 2025, Номер unknown
Опубликована: Янв. 16, 2025
While biomass burning (BB) is the largest source of fine particles in atmosphere, influence relative humidity (RH) and photochemistry on BB secondary organic aerosol (BB-SOA) formation aging remains poorly constrained. These effects need to be addressed better capture comprehend evolution BB-SOA atmosphere. Cresol (C7H8O) used as a proxy investigate these effects. It emitted directly from has been identified significant SOA precursor residential wood-burning emissions. The gas- particle-phase signal intensities are investigated using online mass spectrometers. An increase yield 7% observed when RH rises 0.5–20 70–87%. At elevated RH, nitrogen-containing compounds due processes. This linked net decrease viscosity, enabling formed greater extent at presence nitrogen oxides. results highlight importance particle water content for molecular compounds.
Язык: Английский
Процитировано
0
Atmospheric chemistry and physics, Год журнала: 2025, Номер 25(4), С. 2707 - 2724
Опубликована: Март 3, 2025
Abstract. Solid fuel (SF) combustions, including coal and biomass, are important sources of pollutants in the particle gas phase therefore have significant implications for air quality, climate, human health. In this study, we systematically examined gas-phase emissions, using Vocus proton-transfer-reaction time-of-flight (PTR-TOF) mass spectrometer, from a variety solid fuels, beech logs, spruce/pine branches needles, straw, cow dung, coal. The average emission factors (EFs) organic vapors ranged 4.8 to 74.2 g kg−1, depending on combustion phases types. Despite slight differences modified efficiency (MCE) some experiments, increasing EFs were observed with lower MCE. relative contribution different classes showed large similarities between logs stove burning, change observed. CxHyOz family is most abundant group vapor emitted all SF combustion. However, among these greater nitrogen-containing species CxHy families (related polycyclic aromatic hydrocarbons) dung burning respectively. Intermediate-volatility compounds (IVOCs) constituted fraction emissions combustion, ranging 12.6 % 39.3 %. This was particularly notable needles (39.3 %) (31.1 %). Using Mann–Whitney U test studied identified specific potential new markers fuels based measurements. product pyrolysis coniferyl-type lignin extract cedar pine needle as open (e.g., C10H14O2, C11H14O2, C10H10O2). (C9H12O) marker log burning. Many series homologues C10H11–21NO, C12H11–21N, C11H11–23NO, C15H15–31N) acetonitrile, acrylonitrile, propanenitrile, methylpentanenitrile) specifically emissions. Polycyclic hydrocarbons (PAHs) 9–12 carbons significantly higher abundance compared other fuels. composition reflects burned types can help constrain regional models.
Язык: Английский
Процитировано
0
Journal of Hazardous Materials, Год журнала: 2025, Номер unknown, С. 138139 - 138139
Опубликована: Апрель 1, 2025
Язык: Английский
Процитировано
0
Mass Spectrometry Reviews, Год журнала: 2025, Номер unknown
Опубликована: Май 19, 2025
ABSTRACT In the 1980s, researchers discovered remarkable ability of electrospray plumes to effectively ionize gas‐phase molecules via secondary ionization. Around 20 years later—coinciding with ambient mass spectrometry revolution—secondary ionization (SESI) and extractive (EESI) coupled were revisited further developed analyze complex mixtures gas aerosol samples in real‐time yet high sensitivity. During past two decades, these spectrometric techniques have been applied across a broad range applications, such as detection illicit drugs, environmental analysis, series metabolomic studies through analysis volatiles emitted from living organisms. This review offers comprehensive overview progress SESI EESI applications since their emergence. Finally, we discuss opportunities, challenges, along future directions techniques.
Язык: Английский
Процитировано
0
Atmospheric chemistry and physics, Год журнала: 2025, Номер 25(10), С. 5215 - 5231
Опубликована: Май 21, 2025
Abstract. Styrene is emitted by anthropogenic sources and biomass burning highly reactive towards atmospheric oxidants. While it has the highest nitrate radical (NO3) reactivity among aromatic hydrocarbons, NO3 oxidation of styrene formation mechanisms secondary organic aerosols (SOA) have not been investigated. In this study, we conduct chamber experiments with concentrations ranging from 9.5 to 155.2 ppb. The resulting SOA yields range 14.0 % 22.1 aerosol mass loadings 5.9–147.6 µg m−3 after wall loss corrections. chemical composition characterized online measurements, revealing that dimeric nitrates (ONs) constitute 90.9 total signal particle-phase products. C16H16N2O8 C8H9NO4 are identified as major products, which 88.3 4.1 %, respectively, measured signal. We propose for ON including common RO2+ RO2 / HO2 pathway other chain termination reactions such RO + R R. also investigate hydrolysis particulate ONs. lifetime ONs determined be less than 30 min. This short can attributed stabilization carbocation delocalized π orbitals benzene-related skeleton work provides first fundamental laboratory data evaluate production chemistry. Additionally, reported time, highlighting compounds previously nitroaromatics in ambient field campaigns could
Язык: Английский
Процитировано
0
Journal of Geophysical Research Atmospheres, Год журнала: 2025, Номер 130(11)
Опубликована: Июнь 3, 2025
Abstract This study investigates primary emissions and photochemical aging evolution mechanisms of PM 2.5 Nitroaromatic compounds (NACs) released from solid fuels through conducting field combustion experiments. The emission factors (EFs) NACs are much higher biomass burning (BB) than coal (CC). EFs measured species mostly increased during the process except some in CC. Photochemical significantly enhanced absorbance ∑NACs, but different between BB In BB, increasing production 4‐nitrocatechol (4NC), 4‐nitroguaiacol (4NG), 4‐methyl‐5‐nitrocatechol (4M5NC) nitrogen addition reactions light absorption. CC, 4NC 4‐methyl‐2,6‐dinitrophenol as well indirect photolysis 4NG 4M5NC with ·OH to form organic intermediates both increase Furthermore, oxidation potential substantially auto‐biotoxicity generation facilitating 1 O 2 decomposing into nitro‐quinones
Язык: Английский
Процитировано
0
Journal of Environmental Sciences, Год журнала: 2024, Номер 151, С. 331 - 346
Опубликована: Апрель 6, 2024
Язык: Английский
Процитировано
3
Atmospheric Environment, Год журнала: 2024, Номер 327, С. 120518 - 120518
Опубликована: Апрель 9, 2024
Язык: Английский
Процитировано
2
The Science of The Total Environment, Год журнала: 2024, Номер 950, С. 175326 - 175326
Опубликована: Авг. 6, 2024
Язык: Английский
Процитировано
2