Cheek Mcleod (easemeat3)

This paper reports for the first time the occurrence, fates, and carcinogenic risks of 20 substituted polycyclic aromatic hydrocarbons (SPAHs) and 16 priority PAH species in two coking wastewater treatment plants (WWTPs) (plant E and central WWTP). The measured total concentrations of PAHs and SPAHs in raw wastewater of coking plant E were 3700 and 1200 μg·L-1, respectively, with naphthalene (1400 μg·L-1), and fluoranthene (353 μg·L-1) as dominant PAH species and 2-methylnaphthalene (167 μg·L-1), anthraquinone (133 μg·L-1), and 1-methylnaphthalene (132 μg·L-1) as dominant SPAHs. For the 11 methyl-PAHs (MPAHs), 4 oxygenated-PAHs (OPAHs), and 5 nitrated-PAHs (NPAHs) investigated, the biological wastewater treatment process removed 98.6% MPAHs, 83.9% OPAHs, and 89.1% NPAHs. Mass balance analysis result revealed that transformation was the major mechanism to remove low-molecular-weight (LMW) MPAHs (59.9-77.3%), a large part of OPAHs, including anthraquinone, methylanthraquinone, and 9-fluorenone (46.7-49.6%), and some NPAHs, including 2-nitrofluorene and 9-nitroanthrancene (52.9-59.1%). Adsorption by activated sludge mainly accounted for removing high-molecular-weight (HMW) SPAHs (59.6-71.01%). The relatively high concentrations of SPAHs in excess sludge (15,000 μg·g-1) and treated effluent (104 μg·L-1) are of great concern for their potential adverse ecological impacts. SPAHS exhibited similar behaviors in central WWTP, though the influent concentrations were much lower. The concentration levels of SPAHs in the ambient air of coking plant E and central WWTP may also pose potential lung cancer risks (LCR) to the workers through inhalation, where all studied SPAHs except 3-nitrofluoranthene and 7-nitrobenz[a]anthracene exceeded the acceptable cancer risk standards (>10-6) recommended by U.S EPA. This study could help identify the ecological and healthy risks during coking wastewater treatment and provide useful information for policy-making.Vegetation establishment in urban areas is a potential solution to combat elevated particulate matter (PM) pollution, create cleaner environment for residents and enhance the sustainability of cities. However, vegetation effect at the points of interest in street-canyon on traffic pollutant from multiple interconnected factors (e.g., plant species, vegetation configurations, aerodynamic effect, deposition effect and complex wind regimes) is still not well studied. Therefore, taking roadside vegetation and street canyon as research objects, we evaluated vegetation effect (VE) for vegetation configurations (VCs) with several tree species on the dispersion, deposition, and distribution of traffic generated PM pollutant under different wind regimes. Results showed that (1) the transportation and distribution of traffic PM pollutant were different from wind regimes; (2) total VEs varied from -88.3% to 25.5%, depending on different VCs and wind regimes; perpendicular wind had the best VEs, while oblique wind had thor vegetation establishment from the viewpoint of improving air quality.Carbon/nitrogen ratio is an important parameter during the biological wastewater treatment. Our study emphasizes revealing the mechanisms of chemical oxygen demand/total nitrogen (COD/TN) ratio dependent improved greywater (GW) treatment in an oxygen based membrane biofilm reactor (O2-MBfR). Results showed that reducing COD/TN ratio from 40 to 20 g COD/g N by supplementing NH4Cl to GW improved the relative abundance of genera related to LAS-biodegradation (from 8.39% to 35.7%), nitrification (from 0.20% to 0.62%) and denitrification (from 3.01% to 7.59%). Reducing COD/TN ratio also led to an increase in the ammonia monooxygenase (AMO) activity (from 7.56 to 10.2 mg N/g VSS-h), as well as improved ammoxidation and linear alkylbenzene sulfonate (LAS) mineralization although the dissolved oxygen (DO) concentration and pH decreased. Ricolinostat Much higher NH4+ - N at lower COD/TN ratio (10 units) led to lower DO (0.