Category Ranking
98%
Total Visits
921
Avg Visit Duration
2 minutes
Citations
20
Article Abstract
Measuring the isotopic composition of Hg in natural waters is challenging due to the ultratrace level of aqueous Hg (ng L). At least 5 ng of Hg mass is required for Hg isotopic analysis. Given the low Hg concentration in natural waters, a large volume of water (>10 L) is typically needed. The conventional grab sampling method is time-consuming, laborious, and prone to contamination during transportation and preconcentration steps. In this study, a DGT (diffusive gradients in thin films) method based on aminopropyl and mercaptopropyl bi-functionalized SBA-15 nanoparticles was developed and extended to determine the concentration and isotopic composition of aqueous Hg for the first time. The results of laboratory analysis showed that Hg adsorption by DGT induces ∼ -0.2‰ mass-dependent fractionation (MDF) and little mass-independent fractionation (MIF). The magnitude of MDF exhibits a dependence on the diffusion-layer thickness of DGT. Since Hg-MDF can occur in a broad range of environmental processes, monitoring the δHg of aqueous Hg using the DGT method should be performed with caution. Field results show consistent MIF signatures (ΔHg) between the DGT and conventional grab sampling method. The developed DGT method serves as a passive sampling method that effectively characterizes the MIF of Hg in waters to understand the biogeochemical cycle of Hg at contaminated sites.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acs.analchem.3c01356 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Re-Os geochronology for sulfides and organic-rich sediments.
Natl Sci Rev
September 2025
Department of Earth Sciences, Durham University, Durham DH1 3LE, UK.
Rhenium and osmium are both siderophilic and chalcophilic, exhibiting a strong affinity for organic-rich materials. This makes the Re-Os chronometer a valuable complement to geochronometers based on lithophile elements. In this review, we begin by discussing how the elemental abundances and isotopic compositions impact sample selection, analytical strategy, and data interpretation.
View Article and Find Full Text PDFSoil Carbon Availability Drives Depth-Dependent Responses of Microbial Nitrogen Use Efficiency to Warming.
Glob Chang Biol
September 2025
State Key Laboratory of Vegetation Structure, Function and Construction (VegLab), Ministry of Education Key Laboratory of Earth Surface Processes, and College of Urban and Environmental Sciences, Peking University, Beijing, China.
Microbial nitrogen use efficiency (NUE) describes the partitioning of organic N between microbial growth and N mineralization, which is crucial for assessing soil N retention. However, how warming affects NUE along soil depth remains unclear. Based on a whole-soil-profile warming experiment (0 to 100 cm, +4°C) on the Qinghai-Tibetan Plateau, combined with O and N isotope labeling techniques, we determined soil carbon (C) composition, edaphic properties, and microbial parameters.
View Article and Find Full Text PDFIsotope-dependent Tafel analysis probes proton transfer kinetics during electrocatalytic water splitting.
Nat Chem
September 2025
Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.
Proton transfer plays an important role in both hydrogen and oxygen evolution reactions during electrocatalytic water splitting to produce green hydrogen. However, directly adapting the conventional proton/deuterium kinetic isotope effect to study proton transfer in heterogeneous electrocatalytic processes is challenging. Here we propose using the shift in the Tafel slope between protic and deuteric electrolytes, or the Tafel slope isotope effect, as an effective probe of proton transfer characteristics.
View Article and Find Full Text PDFMapping spatiotemporal variability of wet season surface water processes in the Cuvelai-Etosha Basin, Namibia using stable isotopes.
Isotopes Environ Health Stud
September 2025
School of Architecture and Environment, University of the West of England, Bristol, UK.
The natural tracers δO and δH are essential for tracing hydrological processes by identifying water sources, tracking evaporation loss and floodwater dynamics to enhance water management and flood mitigation strategies. This study employed this approach in the ephemeral, endorheic Cuvelai-Etosha Basin (CEB), spanning northern Namibia and southern Angola, to determine its viability in capturing spatial and temporal hydrological patterns, their timing and interactions during a medium flood condition (2017), and contrasted with a drought year (2014). During the 2017 wet season 219 grab surface water samples were collected from ephemeral waterbodies in four sampling campaigns (February, March, April and May) in addition to a single campaign in May 2014 (63 samples).
View Article and Find Full Text PDFTracing priming effects in palsa peat carbon dynamics using a stable isotope-assisted metabolomics approach.
Front Mol Biosci
August 2025
Department of Environmental Science, University of Arizona, Tucson, AZ, United States.
Introduction: Peatlands store up to a third of global soil carbon, and in high latitudes their litter inputs are increasing and changing in composition under climate change. Although litter significantly influences peatland carbon and nutrient dynamics by changing the overall lability of peatland organic matter, the physicochemical mechanisms of this impact-and thus its full scope-remain poorly understood.
Methods: We applied multimodal metabolomics (UPLC-HRMS, H NMR) paired with C Stable Isotope-Assisted Metabolomics (SIAM) to track litter carbon and its potential priming effects on both existing soil organic matter and carbon gas emissions.