Environmental Technology & Innovation, Год журнала: 2025, Номер unknown, С. 104218 - 104218
Опубликована: Апрель 1, 2025
Язык: Английский
Environmental Science & Technology, Год журнала: 2024, Номер 58(31), С. 13808 - 13819
Опубликована: Июль 24, 2024
This study addresses the fundamental processes that drive photomineralization of dissolved organic matter (DOM) to carbon dioxide (CO
Язык: Английский
Процитировано
6
Environmental Science & Technology, Год журнала: 2025, Номер unknown
Опубликована: Фев. 10, 2025
Advancing a common understanding about the chemical composition, size, and three-dimensional (3D) structure of dissolved organic matter (DOM) is paramount to deciphering its impact on involvement in environmental processes, such as fate transport contaminants carbon cycling. Traditionally, DOM has been described collection solvent-separated molecules or macromolecules. More recently, depicted "supramolecular assembly", individual associations held together by non-covalent interactions. The supramolecular assembly model broadly invoked rationalize certain behaviors properties DOM, yet complexity made it difficult fully unravel nature contributions intermolecular Discussed this perspective evidence regarding thermodynamic drivers associations, molecular sorption optical DOM. While single observations may be rationalized former structural models, model, combined shows that 3D best mixed dynamic (MDAM). MDAM depicts small, tightly knit assemblies strong hydrogen bonds, which form large through weak interactions only at specific pH values, high ionic strength, concentration.
Язык: Английский
Процитировано
0
Environmental Science & Technology, Год журнала: 2025, Номер unknown
Опубликована: Фев. 25, 2025
Triplet-state dissolved organic matter (3DOM*) plays a crucial role in environmental aquatic photochemistry, with 2,4,6-trimethylphenol (TMP) frequently used as chemical probe or quencher due to its high reactivity 3DOM*. However, the influence of TMP-derived oxidation intermediates on target photochemical reactions has not been comprehensively examined. This study investigated TMP's effect photolysis sulfamethoxazole (SMX), common antibiotic found natural waters, presence different DOM sources model photosensitizer. Contrary expectation, TMP significantly accelerated SMX photolysis, extent enhancement depending and concentrations. Laser flash kinetic modeling suggested long-lived reactive species (TMP-RS), including phenoxyl radicals, semiquinone quinones, key factors this process. Unlike 3DOM*, TMP-RS may react formation non-SMX•+ intermediates. process prevents reduction SMX•+ subsequent regeneration SMX. The successfully predicts dynamic contributions various during reaction, highlighting critical TMP-RS. advances our understanding involvement triplet-state photochemistry suggests reconsideration RSs play transformation micropollutants.
Язык: Английский
Процитировано
0
Journal of Hazardous Materials, Год журнала: 2025, Номер unknown, С. 137985 - 137985
Опубликована: Март 1, 2025
Язык: Английский
Процитировано
0
Environmental Science & Technology, Год журнала: 2025, Номер unknown
Опубликована: Март 27, 2025
Hydroxyl radicals (•OH), singlet oxygen (1O2*), and organic triplet excited states (3C*) play key roles as oxidants ("reactive intermediates (RIs)") in forming oxidizing aqueous aerosols. Bioaerosols are ubiquitous the atmosphere, but little is known about their photochemical behavior contributions to atmospheric photochemistry. We investigated of aqueous-phase cellular matter (COM) extracellular polymeric substances (EPS) from cultured bacteria isolated PM2.5, focusing on production 3C*, 1O2*, •OH. The molecular size aromaticity chromophores fluorophores COM EPS increased with weight (MW). Apparent quantum yields (ΦRI) up 10% 5% were measured for 1O2* respectively, which upper range previously reported values. This indicated that contain photosensitizers highly efficient at producing 3C*. ΦRI concentrations ([RI]ss) decreased MW due higher-MW molecules engaging charge-transfer interactions disrupt processes oxidant production. Machine learning models used understand predict based measurable optical chemical properties EPS. study provides new insights into bioaerosols can
Язык: Английский
Процитировано
0
Environmental Science & Technology, Год журнала: 2025, Номер unknown
Опубликована: Апрель 1, 2025
The application of the Bouguer–Lambert–Beer (BLB) Law is limited to dissolved organic matter (DOM) in environment due wide distribution overlapping chromophores with different molar absorptivities (ε). Here, we report our findings demonstrating existence an inverse relationship between ε and spectral slope (S) absorption spectra chromophoric DOM (CDOM). Specifically, values at 275 380 nm are directly proportional square root-mean-square width Gaussian peak (W2) located 4.80 eV (258 nm) 3.79 (327 nm), W2 inversely S right half log-transformed respect wavelength, corresponding 275–295 380–443 spectra, respectively. This finding expands applicability utility BLB uniformly quantify DOC concentrations inland, coastal, pelagic waters (30–3000 μmol·L–1, n = 7745, R2 0.97). Furthermore, aids interpreting absorbance DOM, providing valuable insights into its composition properties. represents a significant advancement expanding applications UV–vis spectroscopy CDOM monitoring from micro global scales.
Язык: Английский
Процитировано
0
Environmental Technology & Innovation, Год журнала: 2025, Номер unknown, С. 104218 - 104218
Опубликована: Апрель 1, 2025
Язык: Английский
Процитировано
0