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Various shipping emission restrictions have recently been implemented locally and nationally, which might mitigate their impacts on regional air quality, climate change, and human health. In this study, the daily trace metal elements in PM1 were measured in a coastal megacity in Northern China, from autumn to winter from 2018 to 2022, spanning DECA 1.0 (domestic emission control area), DECA 2.0, IMO 2020, and Pre-OWG Beijing 2022 stages. The trace element changes of V, Ni, Pb, and Zn in PM1 were analyzed. The concentrations of V declined with shipping emission regulations implemented in 2018–2022 at 3.61 ± 3.01, 1.07 ± 1.04, 0.84 ± 0.62, and 0.68 ± 0.61 ng/m3, respectively, with the V/Ni ratio decreasing at 1.14 ± 0.79, 0.93 ± 1.24, 0.35 ± 0.24, and 0.22 ± 0.18. The V/Ni ratio was dominated by the shipping emissions in the DECA 1.0 stage but has been more affected by the inland sources since DECA 2.0. The V/Ni ratio of local transport air mass was higher than that of long-distance transportation, indicating that some ships were still using high-sulfur fuel oil, especially for the ships 12 nautical miles from the coastline. The multiple linear regression model showed a better fit using V as a tracer for ship emission sources of ambient SO2 in the DECA 1.0 stage, while the indication effect reduced since DECA 2.0. The V and V/Ni ratios should be carefully used as indicators of ship sources as more vessels will use clean fuels for energy, and the contribution of inland sources to V and Ni will gradually increase. [ABSTRACT FROM AUTHOR]

PM2.5 samples were simultaneously collected in the urban and suburban roadside environments during different traffic flow periods at Qingdao, a coastal city located in China. The composition, diurnal variation, sources, and toxicity of PAHs, NPAHs, and OPAHs in PM2.5 were analyzed to discuss the influence of vehicle emissions on the pollution characteristics of these components. The concentrations of PAHs, NPAHs, and OPAHs in the suburban site were slightly higher than those at the urban site, and the concentrations in winter were about four times higher than those in summer. For PAHs and NPAHs, in urban site, morning rush hours and evening rush hours were the two periods with the highest concentrations compared with other sampling periods, which were consistent with the heavy traffic times. However, in the suburban site, the highest concentration peak appeared in the morning rush hours and the second highest peak appeared at night. Three major sources including coal combustion, gasoline vehicles emissions, and diesel vehicles emissions were identified by PMF. Among these three sources, gasoline vehicle emissions contributed the most in summer and coal combustion contributed the highest fraction in winter. Although the number of diesel vehicles passing through the sampling sites was much less than that of gasoline vehicles, the contribution of diesel vehicles emissions was comparable to that of gasoline vehicles, which indicates that more attention should be paid to the governance of diesel vehicles to reduce the pollution of PAHs and their derivatives in the roadside environments. Traffic sources have a great impact on the toxicity of PAHs and NPAHs. [ABSTRACT FROM AUTHOR]

New strategies for highly selective and sensitive detection of highly toxic environmental pollutants are still a pressing need. Here, through Cu2+ metalated porous nanoscale covalent organic framework (NCOF), a novel heterogeneous NCOF fluorescence probe has been synthesized for sensitive and selectivity detection of hydrogen sulfide (H2S). Upon H2S addition, the Cu2+ released from the CuCOF, accompanied by the fluorescence recovered of COF. As far as we know, NCOF has not been reported as fluorescence probe for H2S detection. The as‐prepared nano CuCOF displays an excellent sensitive response to H2S with a detection limit of 10 nM. In addition, such heterogeneous fluorescence probe exhibited high selectivity towards to H2S relative to other thiols and anionic species. Moreover, the detection of H2S was achieved successfully in different actual water samples. [ABSTRACT FROM AUTHOR]

The withered Phragmites australis (PA) surrounding the rivers can cause the secondary pollution of water. In this research, by changing the ratio (R) of ammonium polyphosphate (APP), used as flame retardant, to PA at different temperatures, a series of BC samples were prepared for further analysis in several perspectives, namely, surface morphologies, surface areas, surface functional groups, and yields. The analysis indicated that, after being charred, the produced BCs obtained enhanced yields and promoted surface acidity. As adsorbent to remove Ni(II) from aqueous solutions, the BCs with APP improved the sorption of Ni(II) dramatically, compared with those purely produced by pyrolysis of PA, and obtained the maximum of adsorption capacity with the R of 0.25 at 400°C. [ABSTRACT FROM AUTHOR]