The oxidative potential of fresh and aged elemental carbon-containing airborne particles: a review DOI
Yangyang Liu, Chak K. Chan

Environmental Science Processes & Impacts, Год журнала: 2022, Номер 24(4), С. 525 - 546

Опубликована: Янв. 1, 2022

Elemental carbon is often found in ambient particulate matter (PM), and it contributes to the PM's oxidative potential (OP) thus poses great health concerns. Previous review articles mainly focused on methodologies evaluating OP PM its relationship with selected chemical constituents, including metal ions, PAHs, inorganic species. In recent years, growing attention has been paid effect of atmospheric aging processes EC-containing airborne particles (ECCAPs). This investigates more than 150 studies concerning measurements physico-chemical properties both fresh aged ECCAPs such as laboratory-generated elemental (LGEC), black (CB), soot (black carbon), engineered carbon-containing nanomaterials (ECCBNs). Specifically, we summarize characteristics water-soluble insoluble organic species, quinone, oxygen-containing functional groups (OFGs), EC crystallinity. Both (WSOC) water-insoluble (WIOC) contribute OP. Low molecular weight (MW) PAHs show a higher correlation high MW PAHs. Furthermore, introduce OFGs, where quinone (CO) epoxide (O-C-O) increase ECCAPs. contrast, carboxyl (-COOH) hydroxyl (-OH) slightly change The low crystallinity favors oxygen addition forms active OFG increasing More detailed analyses for microstructures coatings are needed predict

Язык: Английский

ROS-generation potential of Humic-like substances (HULIS) in ambient PM2.5 in urban Shanghai: Association with HULIS concentration and light absorbance DOI

Xiaoya Xu,

Xiaohui Lu, Xiang Li

и другие.

Chemosphere, Год журнала: 2020, Номер 256, С. 127050 - 127050

Опубликована: Май 12, 2020

Язык: Английский

Процитировано

43

Reactive Oxygen Species-Related Inside-to-Outside Oxidation of Soot Particles Triggered by Visible-Light Irradiation: Physicochemical Property Changes and Oxidative Potential Enhancement DOI

Jiali Zhu,

Jing Shang, Yueyue Chen

и другие.

Environmental Science & Technology, Год журнала: 2020, Номер 54(14), С. 8558 - 8567

Опубликована: Июнь 26, 2020

Modifications of the physicochemical properties and oxidative potential (OP) soot due to visible-light irradiation its underlying mechanisms during atmospheric aging have not been elucidated. In this study, two types obtained using different air/fuel ratios (A/F) were aged under visible light with or without ozone (O3) at an atmospherically relevant level in environmental chamber. Physicochemical characteristics OP systematically measured dithiothreitol (DTT) assay (OPDTT). Regardless presence O3, markedly promoted oxidation soot, which led consumption polycyclic aromatic hydrocarbons, formation oxygen-containing functional groups, enhancement OPDTT values. Compared low-A/F high-A/F contained more elemental carbon but less organic was sensitive by exhibiting greater changes. It proposed that initiated inside-to-outside pathway, where reactive oxygen species played important role. This study clarified solar irradiation-triggered self-oxidation process is health effects.

Язык: Английский

Процитировано

41

Comparison of indoor and outdoor oxidative potential of PM2.5: pollution levels, temporal patterns, and key constituents DOI Creative Commons
Fan Yang, Cong Liu, Hua Qian

и другие.

Environment International, Год журнала: 2021, Номер 155, С. 106684 - 106684

Опубликована: Июнь 9, 2021

Oxidative potential (OP) of PM2.5 is an emerging health indicator representing its ability to induce oxidative stress and cause adverse effects. We examined pollution levels, temporal variations, key constituents OP by DTT assay in both indoor outdoor environments Nanjing, China, for over one year. Outdoor OPM (mass-normalized characterizes toxicity) OPV (volume-based overall burden) Nanjing were at a medium level compared results reported twenty-seven cities. Although mass concentration consistently decreased during outdoor-to-indoor transport, varied factor up 2 either direction, indicating change PM2.5's disrupt oxidative-reductive balance. Temporally, exhibited significant seasonality pattern (P < 0.01) as autumn > summer spring winter. daytime-nighttime are fluctuating within two-fold range. In addition, the water-soluble Fe had highest correlation coefficient 0.05) with ΔOPM (ΔOPM = OPM, in-OPM, out) among measured here. Our suggest that development mitigation strategies take into account, instead outdoors only, since they differ.

Язык: Английский

Процитировано

36

Measurement report: Long-emission-wavelength chromophores dominate the light absorption of brown carbon in aerosols over Bangkok: impact from biomass burning DOI Creative Commons
Jiao Tang, Jiaqi Wang, Guangcai Zhong

и другие.

Atmospheric chemistry and physics, Год журнала: 2021, Номер 21(14), С. 11337 - 11352

Опубликована: Июль 28, 2021

Abstract. Chromophores represent an important portion of light-absorbing species, i.e., brown carbon. Yet knowledge what and how chromophores contribute to aerosol light absorption is still sparse. To address this problem, we examined soluble independent in a set year-round samples from Bangkok. The water-soluble fluorescent identified via excitation–emission matrix (EEM) spectroscopy follow-up parallel factor analysis could be mainly assigned as humic-like substances protein-like substances, which differed their EEM pattern that the methanol-soluble fraction. emission wavelength environmental tended increase compared with primary combustion emission, attributed secondary formation or aging process. Fluorescent indices inferred these were not significantly humified comprised mixture organic matter terrestrial microbial origin, exhibited different characteristic biomass burning coal-combustion results. A multiple linear regression revealed larger oxygen-rich highly aromatic high molecular weights key contributors absorption, preferably at longer wavelengths (λmax⁡ > 500 nm). Positive factorization further suggested up 50 % responsible originated emissions.

Язык: Английский

Процитировано

35

The oxidative potential of fresh and aged elemental carbon-containing airborne particles: a review DOI
Yangyang Liu, Chak K. Chan

Environmental Science Processes & Impacts, Год журнала: 2022, Номер 24(4), С. 525 - 546

Опубликована: Янв. 1, 2022

Elemental carbon is often found in ambient particulate matter (PM), and it contributes to the PM's oxidative potential (OP) thus poses great health concerns. Previous review articles mainly focused on methodologies evaluating OP PM its relationship with selected chemical constituents, including metal ions, PAHs, inorganic species. In recent years, growing attention has been paid effect of atmospheric aging processes EC-containing airborne particles (ECCAPs). This investigates more than 150 studies concerning measurements physico-chemical properties both fresh aged ECCAPs such as laboratory-generated elemental (LGEC), black (CB), soot (black carbon), engineered carbon-containing nanomaterials (ECCBNs). Specifically, we summarize characteristics water-soluble insoluble organic species, quinone, oxygen-containing functional groups (OFGs), EC crystallinity. Both (WSOC) water-insoluble (WIOC) contribute OP. Low molecular weight (MW) PAHs show a higher correlation high MW PAHs. Furthermore, introduce OFGs, where quinone (CO) epoxide (O-C-O) increase ECCAPs. contrast, carboxyl (-COOH) hydroxyl (-OH) slightly change The low crystallinity favors oxygen addition forms active OFG increasing More detailed analyses for microstructures coatings are needed predict

Язык: Английский

Процитировано

27