Saved in:
Bibliographic Details
Main Author: Chen, Xiaowen
Format: Recurso digital
Language:
Published: Zenodo 2025
Online Access:https://doi.org/10.5281/zenodo.17305546
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866901042883461120
author Chen, Xiaowen
author_facet Chen, Xiaowen
contents <p><span lang="EN-US">Organic peroxides (POs) are an important component of secondary organic aerosol (SOA) and contribute to the generation of reactive oxygen species associated with adverse health effects. However, their molecular-level evolution upon atmospheric aging, particularly in SOA from typical terpenes like limonene, remains poorly characterized. In this study, limonene SOA was generated in an oxidation flow reactor under controlled OH exposure (equivalent photochemical age, PCA = 0.6-13.2 days). The SOA yield exhibited a nonlinear peak at PCA = 7.4 days, followed by a decline at 13.2 days, a trend that was accompanied by a<span> </span>shift in RO<sub>2</sub> reaction pathways from dimerization to reactions with excess oxidants. POs were quantified using iodometry-assisted high-resolution mass spectrometry (HRMS), and their yields decreased progressively with aging. It was found that 100% of highly oxygenated organic molecules (HOMs) were POs at low OH exposure (0.6 days), whereas only 27% of HOMs were POs at high OH exposure (13.2 days), indicating rapid conversion to non-peroxide, highly oxidized molecules (e.g., acids or esters). Key monomeric (C<sub>8</sub>-C<sub>10</sub>) and dimeric (C<sub>15</sub>-C<sub>19</sub>) species were identified at the molecular level. This work elucidates the fate of POs within aged SOA, highlighting the limitations of using HOMs as proxies for POs, and provides critical information for assessing the health risks of SOA.</span></p>
format Recurso digital
id zenodo_https___doi_org_10_5281_zenodo_17305546
institution Zenodo
language
publishDate 2025
publisher Zenodo
record_format zenodo
spellingShingle Atmospheric aging suppresses the formation of limonene-derived organic peroxides
Chen, Xiaowen
<p><span lang="EN-US">Organic peroxides (POs) are an important component of secondary organic aerosol (SOA) and contribute to the generation of reactive oxygen species associated with adverse health effects. However, their molecular-level evolution upon atmospheric aging, particularly in SOA from typical terpenes like limonene, remains poorly characterized. In this study, limonene SOA was generated in an oxidation flow reactor under controlled OH exposure (equivalent photochemical age, PCA = 0.6-13.2 days). The SOA yield exhibited a nonlinear peak at PCA = 7.4 days, followed by a decline at 13.2 days, a trend that was accompanied by a<span> </span>shift in RO<sub>2</sub> reaction pathways from dimerization to reactions with excess oxidants. POs were quantified using iodometry-assisted high-resolution mass spectrometry (HRMS), and their yields decreased progressively with aging. It was found that 100% of highly oxygenated organic molecules (HOMs) were POs at low OH exposure (0.6 days), whereas only 27% of HOMs were POs at high OH exposure (13.2 days), indicating rapid conversion to non-peroxide, highly oxidized molecules (e.g., acids or esters). Key monomeric (C<sub>8</sub>-C<sub>10</sub>) and dimeric (C<sub>15</sub>-C<sub>19</sub>) species were identified at the molecular level. This work elucidates the fate of POs within aged SOA, highlighting the limitations of using HOMs as proxies for POs, and provides critical information for assessing the health risks of SOA.</span></p>
title Atmospheric aging suppresses the formation of limonene-derived organic peroxides
url https://doi.org/10.5281/zenodo.17305546