walruscanada55
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e., HAAs with relatively higher apparent logKow* caused by elevated solvent sspKa exhibited longer retention times; whereas with a high proportion of aqueous solution, ionic interactions appeared to dominate retention of HAAs, with the more polarizable HAAs exhibiting longer retention times. Using 70/30 (v/v) acetonitrile/1 M aqueous methylamine, the method detection limits were in the range of 0.090-0.216 μg/L for the 11 selected chloro-, bromo- and iodoacetic acids. Finally, this method was applied to monitor HAAs yields in laboratory chlorination experiments and to determine concentrations of HAAs in tap water and wastewater effluent samples.The Orange County Sanitation District (OCSD) is a public agency that provides treatment of wastewater for residents in Orange County, California. The final effluent characteristics at OCSD have been altered in the last 18 years due to the ~20-fold increase of sodium hypochlorite usage for disinfecting waste streams from 2002 to 2010, implementation of the Ground Water Replenishment System (GWRS) in 2008, and conversion to full secondary treatment, together with a major reduction of sodium hypochlorite usage in 2011. This study analyzed infauna data gathered from 1994 to 2016 at the zone of initial dilution (ZID) and reference stations located on the San Pedro Shelf to assess the effects of these treatment process changes on biota in the receiving water. Impacts to the infauna community within the ZID were observed during the period of high chlorine usage, including the increased proportion of the pollution tolerant polychaete Capitella capitata complex from 6.2% in 2003 to nearly 60% in 2010, the lowest Infaunal Trophic Index score in 2009, and the highest Benthic Response Index score in 2006. The degradation of the infauna community in the ZID was correlated with chlorination and was coincidental with the initiation of the GWRS. The infauna community at the ZID recovered rapidly after the implementation of full secondary treatment as indicated by the significant reduction of the relative abundance of C. capitata complex from 59.8% in 2010 to less than 0.1% after 2012, and by the markedly improved community health index scores. This study demonstrated the composition and biointegrity of the infauna community at the ZID varied in response to changes in the wastewater treatment process. Caution should be exercised at wastewater treatment plants when relatively higher dosages of sodium hypochlorite are used over a multi-year period, as this may negatively impact aquatic biota in the receiving water.Air pollution, particularly in urban areas, is a concern for its negative effects on the materials of the built environment. Cities are also home to a large part of our cultural heritage. Air pollution accelerates the natural processes of deterioration of the materials of historic buildings and monuments, causing premature aging and reducing their aesthetic value. The present paper aims to assess the current potential damage due to air pollution on different materials through Europe. Several corrosion and soiling maps were produced by applying widely used dose-response functions. One of the priorities of this study was to provide an estimate of the effects of air pollution on UNESCO World Heritage cultural sites throughout Europe. The potential risk for cultural heritage monuments was estimated on the basis of exceeding tolerable degradation thresholds suggested for each material. The results show that, despite the significant improvements in air quality in Europe over the past few decades, air pollution is still considerable and continues to be an important agent of degradation of cultural heritage, particularly in anthropized areas. Although the methodology used in this study provides a simplified assessment of the likelihood of damage to UNESCO's cultural heritage in Europe from air pollution, it provides a unique perspective and the potential risk is assessed on a common basis. The results obtained contribute to a better understanding of the existing risk deriving from atmospheric pollution and to highlighting those sites, generally located in areas where anthropogenic activity is relevant, that need particular attention. The present paper can serve as a basis for stimulating additional studies and site-specific analyzes, as well as highlighting the need for further measures and policies for atmospheric pollution reduction in cities and in the surroundings of sensitive historic buildings and monuments to prevent further damage.Allelopathy is regarded as an economic and eco-friendly approach for the control of harmful algal blooms (HABs) because allelochemicals degrade easily and cause less pollution than traditional algicides. We first surveyed the inhibitory effect of the traditional medicinal plant Cerbera manghas L. on the notorious dinoflagellates Alexandrium tamarense, Scrippsiella trochoidea, and Karenia mikimotoi. Then, we identified and quantified the potential algicidal compounds by UPLC-MS and determined their activity. The aqueous extract inhibited algae with EC50-120 h at 0.986, 1.567 and 1.827 g L-1 for A. tamarense, S. trochoidea, and K. mikimotoi, respectively. Cytosporone B Three potential allelochemicals were quantified in the stock solution quinic acid (QA) (28.81 mg L-1), protocatechuic acid (PA) (53.91 mg L-1), and phloridzin (PD) (26.17 mg L-1). Our results illustrated that 1) QA did not have an inhibitory effect, 2) PA had medium toxicity to algae (EC50-120h 0.22, 0.28, and 0.35 mM for A. tamarense, S. trochoidea, and K. mikimotoi), and 3) PD had low toxicity (EC50-120h > 0.66 mM). These findings suggested that PA might be the main allelopathic compound in the aqueous extract of the studied algae. In addition, PA could have a negative effect on the photosynthesis of S. trochoidea by impeding the reduction of quinone electrons and destroying electron transfer in PSII. In summary, this was the first study to quantify allelochemicals in C. manghas fruit. Moreover, C. manghas and protocatechuic have the potential to be algicides to control and mitigate the HABs caused by dinoflagellates.This study aimed to evaluate the influence of two different feeding modes on wastewater treatment performance and oxygen consumption rate (OCR) of the unsaturated (UVF wetland) and partially saturated (SVF wetland) vertical flow constructed wetlands operated in parallel under subtropical climate for four years. Each wetland had a superficial area of 7.5 m2 and was planted with Typha domingensis. Both units have a filter media depth of 0.75 m, composed by sand (effective diameter of 0.29 mm and uniformity of 4). UVF wetland operated typically unsaturated, while SVF wetland had the bottom part saturated (57% of total depth). Two feeding modes were evaluated for both wetlands. The feeding mode was operated within the limits recommended by the German standard, with a hydraulic loading rate (HLR) of 75 mm d-1 and specific pulse volume (SPV) of 19 L m-2 for both wetlands and a specific hydraulic loading rate (SHLR) of 8 and 9 L m-2 min-1 for UVF and SVF wetlands, respectively. Meanwhile, the second feeding mode was applied for both wetlands, being an HLR of 103 mm d-1, 26 L m-2 of SPV, and 4 L m-2 min-1 of SHLR.

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