Biogenic and Anthropogenic Secondary Organic Aerosols Become Fluorescent after Highly Acidic Aging DOI Creative Commons
Cynthia Wong,

Jett Vuong,

Sergey A. Nizkorodov

et al.

The Journal of Physical Chemistry A, Journal Year: 2024, Volume and Issue: 128(36), P. 7657 - 7668

Published: Aug. 30, 2024

Primary biological aerosol particles (PBAPs) and secondary organic (SOA) both contain compounds that share similar chemical optical properties. Fluorescence is often used to characterize PBAPs; however, this may be hindered due interferences from fluorophores in SOA. Despite extensive efforts understand the aging of SOA under elevated particle acidity conditions, little known about how these processes affect fluorescence thereby their interference with measurements PBAPs. The objective study investigate influence on properties aerosols potential for analysis bioaerosols. was generated by O3- or OH-initiated oxidation d-limonene α-pinene, as well toluene xylene. were then aged exposure varying concentrations aqueous H2SO4 2 days. Absorption spectrophotometry examine changes before after aging. key observation appearance strongly light-absorbing fluorescent at pH = ∼−1, suggesting a major driver biogenic precursors (d-limonene α-pinene) resulted stronger than absorption spectra changed drastically shape upon dilution, whereas shapes remained same, chromophores are separate sets species. overlapped PBAPs, exposed highly acidic conditions can confused PBAPs detected fluorescence-based methods. These likely play role atmospheric regions where high persist, such upper troposphere lower stratosphere.

Language: Английский

Evolution from basic to advanced structure of fulvic acid and humic acid prepared by food waste DOI
Daichen Mu,

Linying Mu,

Xinyu Geng

et al.

International Journal of Biological Macromolecules, Journal Year: 2023, Volume and Issue: 256, P. 128413 - 128413

Published: Nov. 27, 2023

Language: Английский

Citations

26
Photochemical behavior of dissolved organic matter in environmental surface waters: A review DOI Creative Commons
Yichen Xu, Yutong Zhang,

Longlong Qiu

et al.

Eco-Environment & Health, Journal Year: 2024, Volume and Issue: 3(4), P. 529 - 542

Published: July 3, 2024

As an important group of widespread organic substances in aquatic ecosystems, dissolved matter (DOM) plays essential role carbon recycling and transformation processes. The photochemical behavior DOM is one the main ways it participates these processes, attracts extensive attention. However, due to a variety sources water conditions, including both freshwater seawater environments, properties exhibit great differences. Nowadays, large number studies have focused on generation process reactive species (RS) from sunlit DOM, while little effort has been made so far provide comprehensive summary especially fresh saline ecosystems. In this review, we analyzed research hotspot photochemistry over last 30 years, summarizing photoreactive natural environments containing (both seawater) listing factors affecting rate, yield, RS photoproduction. Compared with freshwater, unique characteristics such as high pH value, ionic strength, halide ions, which affect photogeneration RS, photoconversion process, well reaction pathways various environmental substances. general, DOM-induced surface impacts toxic effects pollutants can even contribute significantly Earth's cycle, would potential implications for human ecological health.

Language: Английский

Citations

9
Long-term monitoring of cloud water chemistry at Whiteface Mountain: the emergence of a new chemical regime DOI Creative Commons
Christopher Lawrence,

Paul Casson,

Richard E. Brandt

et al.

Atmospheric chemistry and physics, Journal Year: 2023, Volume and Issue: 23(2), P. 1619 - 1639

Published: Jan. 27, 2023

Abstract. Atmospheric aqueous chemistry can have profound effects on our environment. The importance of within the atmospheric phase started gaining widespread attention in 1970s as there was growing concern over negative impacts ecosystem health from acid deposition. Research at mountaintop observatories including Whiteface Mountain (WFM) showed that gas sulfur dioxide emissions react cloud droplets to form sulfuric acid, which also impacted air quality by increasing aerosol mass loadings. current study updates long-term trends water composition WFM for period 1994–2021, with special consideration given samples traditionally been excluded analysis due inorganic charge imbalance. We emphasize three major findings: (1) a abundance total organic carbon (TOC), annual median concentrations more than doubling since measurements began 2009, (2) imbalance between measured cations and anions, consistent independent rain observations, implying substantial fraction anions are no longer being historical suite measurements, (3) number exhibiting greater ammonium sulfate plus nitrate concentrations, now routinely describes one-third samples. Organic acids identified most likely candidates missing ion correlates strongly TOC concentrations. An “inferred droplet pH” is introduced estimate pH vast majority they reside atmosphere using simple method account expected mixing state calcium magnesium containing particles. While inferred closely matches bulk during early years monitoring program, discrepancy found latter half record. interpret these observations indicating acidity accounted sulfate, Altogether, indicate chemical system has shifted away dominated controlled base cations, reactive nitrogen species compounds. Further research required understand quality, climate health.

Language: Английский

Citations

22
Efficient extraction and formation mechanism of fulvic acid from lignite: Experimental and DFT studies DOI
Na Li, Hang Ma, Guodong Wang

et al.

Journal of Environmental Management, Journal Year: 2024, Volume and Issue: 365, P. 121650 - 121650

Published: July 4, 2024

Language: Английский

Citations

3
Compositional and optical characteristics of aqueous brown carbon and HULIS in the eastern Indo-Gangetic Plain using a coupled EEM PARAFAC, FT-IR and 1H NMR approach DOI

Supriya Dey,

Sayantan Sarkar

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 921, P. 171084 - 171084

Published: Feb. 20, 2024

Language: Английский

Citations

2
Aqueous Photosensitization of Syringaldehyde: Reactivity, Effects of Environmental Factors, and Formation of Brown Carbon Products DOI
Fenghua Li, Shengzhen Zhou, Jun Zhao

et al.

ACS Earth and Space Chemistry, Journal Year: 2024, Volume and Issue: 8(6), P. 1193 - 1203

Published: May 18, 2024

Phenolic aldehydes as brown carbon (BrC) chromophores may contribute to the mass of aqueous secondary organic aerosol (aqSOA) due their potential atmospheric photosensitizers. However, there is still a lack knowledge about sensitizing ability and impact environmental factors. In this work, we studied photosensitized behavior phenolic aldehyde, syringaldehyde (SyrAld), in solutions. Under illumination, influences factors such precursor concentration, solution pH, codissolved inorganic constituents (NaCl Na2SO4), matter (vanillyl alcohol, VAL, methoxyphenol produced during biomass burning) were investigated. Our results show that increasing pH salt concentration causes strong red shift absorption peak SyrAld, chloride salts sulfate exert different effects on photochemical reactivity SyrAld. Interestingly, opposite SyrAld VAL oxidation observed at wavelengths light. UV-B irradiation, inhibited degradation by light shielding effect, while under UV-A photosensitization promoted degradation. The major photooxidation products identified hydroxylated induced reactive oxygen species (OH radicals) dimerized direct triplet excited state (3SyrAld*) using UPLC-Q-TOF-MS. This work suggests play significant roles determining fate waters.

Language: Английский

Citations

2
Effects of Copper on the Chemical Kinetics and Brown Carbon Formation in the Aqueous ∙OH oxidation of Phenolic Compounds DOI
Junwei Yang,

Tianye Zhou,

Yuting Lyu

et al.

Environmental Science Processes & Impacts, Journal Year: 2024, Volume and Issue: 26(9), P. 1526 - 1542

Published: Jan. 1, 2024

Many phenolic compounds (PhCs) in biomass burning and fossil fuel combustion emissions can partition into atmospheric aqueous phases (

Language: Английский

Citations

2
Molecular characteristics of dissolved organic matter regulate the binding and migration of tungsten in porous media DOI
Weijun Li,

Jian Xie,

Rui Huang

et al.

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 954, P. 176670 - 176670

Published: Oct. 2, 2024

Language: Английский

Citations

2
Characterizing water-soluble brown carbon in fine particles in four typical cities in northwestern China during wintertime: integrating optical properties with chemical processes DOI Creative Commons
Miao Zhong, Jianzhong Xu, Huiqin Wang

et al.

Atmospheric chemistry and physics, Journal Year: 2023, Volume and Issue: 23(19), P. 12609 - 12630

Published: Oct. 10, 2023

Abstract. Brown carbon (BrC) aerosol could impact atmospheric radiative forcing and play a crucial role in photochemistry. In this study, fine particulate matter (PM2.5) filter samples were collected synchronously four major cities northwestern China during the winter season (December 2019–January 2020): Lanzhou (LZ), Xining (XN), Yinchuan (YC), Ürümqi (UR), which are represented as energy-producing heavy manufacturing China. The primary aim of study is to explore optical properties, sources, chemical processes water-soluble BrC (WS-BrC). average mass absorption efficiency at 365 nm (MAE365) WS-BrC these was 1.24 ± 0.19 m2 g−1 1.19 0.12 1.07 0.23 0.78 0.16 (UR). properties further investigated by an acid–base titration experiment. results showed that MAE365 values all increased with higher pH (2–11), while fluorescence intensities water extracts fluctuated values, being stronger under both highly acidic basic conditions. sensitivity variation most pronounced from YC LZ, indicating important contribution acid or base functional group compounds locations. Additionally, revealed significant photo-enhancement (LZ) photo-bleaching (YC UR) phenomena different cities. These suggest sources and/or varied among explored combination parallel factor analysis (PARAFAC) on excitation–emission matrix (EEM) spectra positive factorization (PMF) high-resolution organic (WSOA). Six PARAFAC components identified, including three humic-like substances (HULIS; two less oxygenated (LO) HULIS one (HO) HULIS), protein-like phenol-like (PLS), undefined substance. Four PMF factors OA (WS-POA), oxidized associated coal combustion-induced WSOA (LO-OOA), OAs resulting photochemical oxidation aqueous-phase transformations (HO-OOA1 HO-OOA2). WS-POA determined be source light absorption, accounting for 30 %–60 % based multiple linear regression models, it correlation PLS LO-HULIS components. loss found occur through its conversion LO-OOA HO-OOAs aqueous reactions, significantly correlated HO-HULIS component. can clearly illustrated integrating composition using Van Krevelen diagram EEM plot.

Language: Английский

Citations

6
Compact fiber sensor for pH measurement based on the composite effect of hydrogel deformation and LC refractive index variation DOI

Zhenyu Ma,

Jing Sun,

Sijie Zhou

et al.

Optics Letters, Journal Year: 2022, Volume and Issue: 48(1), P. 139 - 139

Published: Nov. 28, 2022

A novel, to the best of our knowledge, type compact pH fiber sensor combined with a hydrogel based on whispering gallery mode (WGM) is proposed and integrates liquid crystal (LC) microdroplet in capillary structure as small 180 µm. In research, performs both supporting frame responsive material that causes morphological deformation LC variation. Moreover, new phenomenon pH-induced refractive index variation observed applied measurement, so acid itself can also lead transition. Thus, WGM method detect composite effect simultaneously improve sensing capability. The sensitivity range from 4.55 6.86 reaches 3.19 nm/pH. response time short, within 60 s. simple reduces cost enhances stability, which great potential for biomedical measurement.

Language: Английский

Citations

10