Microplastic (MP) pollution has become a global concern given its wide occurrence and potential ecological risks. The retention/transport features of MPs in porous media govern the fate and risks of MPs in subsurface environments. Polystyrene (PS) microspheres are employed as representative MPs to explore the migration behaviors in water-saturated quartz sand columns. The hydrodynamic size mainly determines the deposition and size exclusion straining of MPs in porous media, and further the attachment efficiency. PS50 (PS with 50 nm diameter) shows a total migration rate greater than 85% in each of the studied conditions. In contrast, PS500 commonly exhibits slower migration velocities and higher attachment efficiencies than those of PS50 and PS100. The ionic strength, pH, and dissolved organic matter content of the solution show obvious effects on the retention/transport of PS MPs. The influences of solution chemical properties are consistent with the prediction of Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. The results in this study clarify the size-dependent migration characteristics of MPs in porous media and provide a basis for risk assessment of MPs in terrestrial environments.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.scitotenv.2021.152154 | DOI Listing |
Talanta
January 2025
College of Chemistry and Bioengineering, Guilin University of Technology, Guilin, 541004, China.
Monitoring reactive nitrogen species (RNS) in complex biological media is essential for evaluating the health status of living organisms; however, biofouling on the sensor surface restricts its applications. To overcome this issue, we developed an antifouling electrochemical sensing platform using copper-platinum bimetallic nanoparticles/N-doped biomass porous carbon fibres (Cu-PtNPs/N-BCF) for directly detecting peroxynitrite anion (ONOO), a major type of RNS. Cyclic voltammetry measurements demonstrated that the Cu-PtNPs/N-BCF-2 nanocomposite, synthesised at a molar ratio of 1:1 between Co and Zn, exhibited exceptional electrocatalytic activity for ONOO oxidation.
View Article and Find Full Text PDFPLoS One
January 2025
Cooperative Innovation Center of Unconventional Oil and Gas, Yangtze University (Ministry of Education & Hubei Province), Wuhan, Hubei, China.
This paper develops a finite element analysis model to investigate the seepage characteristics of cement sheaths, considering the flow properties of their porous medium. The model's applicability under various conditions was evaluated through grid sensitivity tests and model validation, indicating that it effectively captures the seepage behavior of cement sheaths with a reasonable degree of reliability. Key parameters, including cement sheath length, permeability, gap structure, pressure differential, and fluid properties, were analyzed using finite element methods to determine their impact on seepage flow.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China; Key Laboratory of Plant Nutrition and the Agro-environment in Northwest China, Ministry of Agriculture, Yangling 712100, China. Electronic address:
The interactions between microplastic-derived dissolved organic matter (MPs-DOM) and heavy metals (Cu, Pb, and Cd) regulate the complex environmental transport behavior of pollutants in terrestrial and aquatic environments. In this study, fluorescence excited emission matrix spectroscopy combined with parallel factor analysis (EEM-PARAFAC) and electrospray ionization coupled Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) were employed to investigate the complexation mechanism of MPs-DOM with heavy metals, as well as the effects of different environmental occurrences of MPs-DOM on the transport behaviors of heavy metals in saturated porous medium. The findings demonstrated that MPs-DOM, particularly humic-like substances containing aromatic structures and various oxygen functional groups, could form stable complexes with heavy metals.
View Article and Find Full Text PDFJ Chromatogr A
January 2025
School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou, 450001, China; Henan Key Laboratory of Cereal and Oil Food Safety and Nutrition, Zhengzhou, 450001, China. Electronic address:
Food safety problem caused by aflatoxins (AFs) has become a major concern worldwide. However, due to the complexity of food matrices and the low concentration of analytes, the accurate and sensitive determination of AFs and their precursors in the biosynthetic pathway is extremely challenging, so the development of efficient sample preparation techniques has been urgently required. This paper reviews the recent advances in sample preparation based on some emerging extraction media for the determination of AFs and their precursors in different food samples, including ionic liquids (ILs) and IL-based composites, metal-organic frameworks (MOFs) and covalent organic frameworks (COFs).
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004 PR China. Electronic address:
Low-cost and effective electrocatalysts are critical for energy storage and conversion. Herein, iron(III) and vanadium(III) acetylacetonates were first adsorbed and confined in porous zeolitic imidazolate framework-8 (ZIF-8), which further cross-linked together by the methanol-induced-assembly. Following the pyrolysis, the FeVO nanoparticles were efficiently encapsulated within three-dimensional (3D) N-doped interconnected porous carbon, termed FeVO/NIPC.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!