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To research the environmental behavior of chiral pesticides in waters and sediments in the Wuhan section of the Yangtze River basin and evaluate their ecological risk, a quantitative method for the detection of 12 chiral pesticides was established based on ultra performance liquid chromatography-electrospray (UPLC) ionization (ESI) tandem triple quadrupole mass spectrometry. The analysis results suggest that the overall a low detection rates and concentrations of the 12 chiral pesticides in surface waters and surface sediments, but the concentrations of paclobutrazol, tebuconazole and hexaconazole were relatively high among them. All the chiral pesticides detected in this study area have stereoselectivity, with S-Paclobutrazol and (-)-Hexaconazole being preferentially degraded in most of the study area, while the stereoselective degradation pattern of tebuconazole was more complicated. ECOSAR simulation method allows deriving that hexaconazole poseded a low (or lower) ecological risk to aquatic algae and paclobutrazol had a low (or even higher) ecological risk to whole aquatic organisms. The levels of most other chiral pesticide residues were acceptable.

Lakes are considered sentinels of terrestrial environmental change. Nevertheless, our understanding of the impact of catchment anthropogenic activities on nutrients and the partial pressure of carbon dioxide (pCO

Danjiangkou Reservoir is the water source of the mid-route of the South-to-North Water Transfer Project. The source, distribution and potential risk of antimony in its water and sediments are rarely reported. In this study, symmetrical investigation results demonstrated that the concentration of antimony in the Han sub-reservoir and water in front of the dam fluctuated at about 0.9 mg L−1, while it was relatively higher and increased with the distance from the dam in Dan sub-reservoir water, with an annual average of 0.93~3.15 mg L−1. In recent years, the concentration of antimony in the Danjiangkou Reservoir showed a downward trend, and the difference between the Han and Dan sub-reservoirs decreased significantly. The antimony in the sediments in the reservoir was primarily derived from the inflowing rivers, and it was higher in the Dan sub-reservoir than in the Han sub-reservoir. The concentration of antimony in the water in the reservoir was considerably higher than the background value in the watersheds, indicating that there is an external input with decreasing input intensity. The content of antimony in the sediments in the reservoir and its inflow rivers was substantially higher than the background value of watersheds, indicating that there is a certain degree of enrichment. In addition, the antimony mining industry in the water source area poses a risk to the water safety of the reservoir. Antimony is not a conventional pollutant. Consequently, the collection of antimony monitoring results is a challenging task. Additionally, this study fills the gap in regional antimony research. Furthermore, the ecological risk assessment of antimony in China is still in its infancy. Unquestionably, the study of the temporal and spatial distribution of antimony concentration will be beneficial for the protection of water sources in relevant regions.

We report a facile route to fabricate free-standing NiFe hydroxides by corrosion engineering as high-performance bifunctional electrocatalysts for seawater splitting. Compared with H2SO4 and HNO3, HCl can promote the dissolution of Ni2+ from NiFe foam and the in situ formation of active NiFe hydroxides due to the strong interaction between Cl- and metal. In situ Raman spectroscopic characterization reveals that HCl corrosion induced NiFe hydroxides (HCl-c-NiFe) can generate oxygen evolution reaction (OER) active NiOOH species at a low potential of 1.4 V vs. reversible hydrogen electrode (RHE) and exhibits equally respectable activity for the hydrogen evolution reaction (HER). During a 1000 h test in an alkaline electrolyte or a 300 h test in an alkaline seawater electrolyte within a two-electrode system at 100 mA cm-2, the cell exhibits outstanding stability and high Cl- tolerance with a low working voltage of 1.62 V, outperforming benchmark Pt/IrO2 and most of the reported bifunctional catalysts.