The aggregation and deposition processes of marine microplastics are extremely important in marine ecosystems. The main effect of these two physical processes is the transfer of surface microplastics to the deep sea, and the underlying kinetics can be significantly affected by the organic matter in the ocean. The morphology of and interaction force on 20-μm polystyrene microplastics in the presence of organic matter were studied by using environmental scanning electron microscopy (ESEM) and atomic force microscopy (AFM), respectively. Experiments were performed using organic matter of various concentrations, and the results showed that humic acid formed a translucent organic film around polystyrene microplastics. With increasing total organic content (TOC), the average overall size of the microplastic coated with biofilm increased up to 11 % (at a TOC of 50 mg/L) and then decreased slightly. The biofilm formed by humic acid decreases the repulsion force between two particles and thus could promote the aggregation process significantly. A modified formulation of eXtended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, describing the interaction force of microplastics with the influences of biofilms was proposed based on the measured results.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2022.157186DOI Listing

Publication Analysis

Top Keywords

organic matter
16
polystyrene microplastics
12
interaction force
8
humic acid
8
microplastics
6
organic
5
effects organic
4
matter
4
matter interaction
4
interaction forces
4

Similar Publications

We review the current state of understanding of Ceres as it relates to planetary protection policy for future landed missions, including for sample return, to the dwarf planet. The Dawn mission found Ceres to be an intriguing target for a mission, with evidence for the presence of regional, possibly extensive liquid at depth, and local expressions of recent and potentially ongoing activity. The Dawn mission also found a high abundance of carbon in the regolith, interpreted as a mix of carbonates and amorphous carbon, as well as locally high concentrations of organic matter.

View Article and Find Full Text PDF

Palladium-Catalyzed Oxidative Allene-Allene Cross-Coupling.

J Am Chem Soc

January 2025

Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-10691 Stockholm, Sweden.

Direct cross-coupling reactions between two similar unactivated partners are challenging but constitute a powerful strategy for the creation of new carbon-carbon bonds in organic synthesis. [4]Dendralenes are a class of acyclic branched conjugated oligoenes with great synthetic potential for the rapid generation of structural complexity, yet the chemistry of [4]dendralenes remains an unexplored field due to their limited accessibility. Herein, we report a highly selective palladium-catalyzed oxidative cross-coupling of two allenes with the presence of a directing olefin in one of the allenes, enabling the facile synthesis of a broad range of functionalized [4]dendralenes in a convergent modular manner.

View Article and Find Full Text PDF

Hydrogen is a zero-emissive fuel and has immense potential to replace carbon-emitting fuels in the future. The development of efficient H sensors is essential for preventing hazardous situations and facilitating the widespread usage of hydrogen. Chemiresistors are popular gas sensors owing to their attractive properties such as fast response, miniaturization, simple integration with electronics and low cost.

View Article and Find Full Text PDF

Intrinsic Mechanical Effects on the Activation of Carbon Catalysts.

J Am Chem Soc

January 2025

CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology (NCNST), Beijing 100190, China.

The mechanical effects on carbon-based metal-free catalysts (C-MFCs) have rarely been explored, despite the global interest in C-MFCs as substitutes for noble metal catalysts. Stress is ubiquitous, whereas its dedicated study is severely restricted due to its frequent entanglement with other structural variables, such as dopants, defects, and interfaces in catalysis. Herein, we report a proof-of-concept study by establishing a platform to continuously apply strain to a highly oriented pyrolytic graphite (HOPG) lamina, simultaneously collecting electrochemical signals.

View Article and Find Full Text PDF

Long-term effects of combining anaerobic digestate with other organic waste products on soil microbial communities.

Front Microbiol

January 2025

Agroécologie, French National Institute for Agriculture, Food, and Environment (INRAE), Institut Agro, Université Bourgogne, Université Bourgogne Franche-Comté, Dijon, France.

Introduction: Agriculture is undergoing an agroecological transition characterized by adopting new practices to reduce chemical fertilizer inputs. In this context, digestates are emerging as sustainable substitutes for mineral fertilizers. However, large-scale application of digestates in agricultural fields requires rigorous studies to evaluate their long-term effects on soil microbial communities, which are crucial for ecosystem functioning and resilience.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!