Edvardsenhovgaard2001

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The degradation of emerging pollutant artificial sweetener sucralose (SUC) using UV/persulfate (UV/PS). The effects of several process parameters, including UV light intensity, PS dosage, pH, and anion concentration, were also investigated. The degradation products and their toxicity during the UV/PS process were further analyzed and evaluated. It is reported that, compared with single UV or PS, the degradation of SUC by UV/PS was more obvious. The degradation rate constants increased with an increase in the light intensity and PS dosage. The SUC degradation could be improved under neutral conditions. The background ions NO3- and HCO3- could inhibit the degradation process, while Cl- and SO42- ions could accelerate the process. Sixteen intermediate products were identified using high-resolution mass spectrometry (HRMS) and GC-MS. Hydroxylation, oxidation, ether cracking, and other reactions were involved. A degradation path was further proposed. Moreover, luminescent bacteria toxicity test and ECOSAR prediction showed that the intermediates with higher toxicity could be produced during UV/PS, which could pose a potential threat to the ecological environment.A Cu0/PMS system mainly relies on the leaching of copper ions to degrade the pollutants and adapt to the narrow pH range ( less then 7). To solve this defect, we studied the properties and reaction mechanism of Cu0@Fe3O4 magnetic core-shell material, which was successfully prepared using co-precipitation method, taking PNP as the target pollutant. The results showed that ① a degradation rate of 96% can be achieved within 60 min for 5 mg ·L-1 PNP, 200 mg ·L-1 Cu0@Fe3O4, and 0.5 mmol ·L-1 PMS at a natural pH value (5.65); ② the Cu0@Fe3O4/PMS system can be regarded as a heterogeneous reaction system because TCu, TCu+, and iron leaching were almost negligible; ③ on comparing the performance of the Cu0@Fe3O4/PMS system and Cu0/PMS system in the pH range of 3 to 11, it was discovered that the method by which Cu0 activates the PMS to degrade the PNP was successfully changed by coating a layer of Fe3O4. The Cu0@Fe3O4/PMS system has a good degradation performance towards PNP in the pH range of 5-9; ④ SO-4 · and HO · existed in the reaction system, and their contribution rates to the reaction system were 34% and 60% ; HO · was the dominant free radical; ⑤ A bimetallic synergy exists between Fe and Cu. The presence of Cu(Ⅰ) can promote the reduction of Fe(Ⅲ) to Fe(Ⅱ), thereby forming a good redox cycle and improving the durability of the reaction system.Practical use of heterogeneous Fenton-like catalysis is inhibited by poor mass transfer and slow conversion of Fe(Ⅲ) to Fe(Ⅱ). In this study, we prepared a novel iron-copper bimetallic organic framework (MIL-101 (Fe,Cu)) using the solvothermal method, and carefully investigated its interfacial characters, catalytic efficacy toward dyes with methylene blue as a model pollutant, and the catalytic activating mechanisms involved in it. The MIL-101(Fe,Cu) exhibited a three-dimensional octahedral shape with a complete crystal structure. The specific BET surface area and average pore size were determined to be as high as 667.2 m2 ·g-1 and 1.9 nm, respectively. These characteristics benefits the exposure of the reactive sites and accelerates mass transfer accordingly. The MIL-101(Fe,Cu)/H2 O2 exhibited promising efficiency toward the degradation of methylene blue in a wide pH range; moreover, at a pH value of 5, the removal efficiency observed was as high as 100% after 20 min of reaction, which was 43.1% and 88.9% higher than that of MIL-101(Fe)/H2 O2 and H2 O2, respectively. Hydroxyl radical ( ·OH) is a dominant active species involved in the degradation of methylene blue using MIL-101(Fe,Cu)/H2 O2 as indicated in radicals quenching experiments. The results of species transformation in Fe and Cu indicated that Cu(Ⅱ) doping provided more active sites, and the Cu(Ⅱ)/Cu(Ⅰ) and Fe(Ⅲ)/Fe(Ⅱ) cycles synergistically facilitated ·OH generation to improve the Fenton-like catalytic efficiency accordingly. The MIL-101(Fe,Cu) as a novel heterogeneous Fenton-like catalyst achieved good performance without any significant pH adjustment and is practically viable for industrial wastewater treatment.Determining the influence of pervious/impervious underlying surface pattern (composition, position, proportion, etc.) on the generation capacity of surface runoff and pollution in the urban parcel-based catchment could aid in alleviating the urban waterlogging and control non-point source pollution significantly. Landscape metrics were used to analyze the relationship between the characteristics of pervious/impervious underlying surface pattern and total runoff (Q) and the cumulative load of dissolved pollutants (Ld) and particulate pollutants (Lp). The results showed that ① For the metrics of fragmentation, the patch density (PD) was positively correlated with Q and Ld. and largest patch index (LPI) was negatively correlated with them. Resatorvid Especially, the PD exhibited a significantly positive correlation with Ld(r=0.59, P less then 0.05, calculated in COD). However, the LPI exhibited a significantly negative correlation with Ld (r=-0.60, P less then 0.05, calculated in COD). ② For the metrics of complexity, landelationship of the fragmentation, complexity, and vergence of pervious/impervious surface, with the runoff generation, and pollution output in parcel-based catchment was analyzed, which provided a new method for rainfall runoff and pollution control by considering rational allocation of LID facilities in terms of its pattern characteristics (area, distance, shape, etc.).Microplastic pollution due to land runoff has gained increasing attention as it is closely associated with human beings. In this study, we analyzed the occurrence characteristics of microplastics in drainage channel and main drainage channel in Hetao irrigation district of Inner Mongolia and estimated its quality. Through field sampling, the density separation of suspension method and microscope observation, Fourier infrared spectrum measurement, and proportional flow method, the abundance distribution, shape, color, particle size, and chemical composition of microplastics in the water body and sediment of the drainage channel and main drainage channel in the Hetao irrigation district were identified. The mass of microplastics transported in the main drainage channel was also estimated. The results showed that the value range of microplastic abundance in the water body of the drainage channel and the main drainage channel in Hetao irrigation district was 2880-11200 n ·m-3, and the value range of microplastic abundance in the sediment was 100-292 n ·kg-1.

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