Macronutrientinduced modulation regarding periodontitis in rodentsa methodical assessment

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Results of the study show that residual dissolved Al in coagulated water can be controlled by affecting theAl binding sites in DOM by pre-oxidation before coagulation. The nature of pre-oxidation agent and its dosage should be selected depending on the quality of the raw water to be treated. Ozonation was concluded to be preferable pre-oxidation agent for the water in examined this study.Groundwater is an important drinking water resource. To ensure clean drinking water, managed aquifer recharge (MAR) could be an attractive solution when recharging with treated wastewater. The installation of reactive barriers, e.g. with compost or other organic materials at MAR facilities, may improve pollutant removal. To link pollutant transformation processes and microbiology in reactive barriers, we simulated infiltration through different sand-compost mixtures using laboratory columns with depth-specific sampling of water and barrier material. We also evaluated the effect of inoculation with activated sludge. Our focus was on the simultaneous removal of organic micropollutants and nitrogen species, with parallel monitoring of the development of microbial communities. During 17 weeks of operation, the columns were fed with synthetic wastewater containing five organic micropollutants (1-2 µg/L each) and ammonium (2 mg N/L). Unique communities developed in the columns in relation to barrier material, with h on the type of pollutant.The recent development of successful model approaches that predict the photochemical behaviour of surface waters has greatly aided in the understanding of how water environments work and will likely work in the future, from a photochemical point of view. However, the inherent multi-wavelength (polychromatic) nature of environmental photochemistry causes the relevant mathematics to be quite complex, which discourages many scientists to carry out photochemical calculations. To greatly simplify model mathematics, this paper proposes a new approach that is based on a monochromatic approximation to the polychromatic problem, introducing the concept of what is here defined as equivalent monochromatic wavelengths (EMWs). The EMW is the single wavelength that reproduces the behaviour of the polychromatic system, using a monochromatic (Lambert-Beer based) equation. The EMW approach largely simplifies calculations, getting rid of integrals and allowing for much more straightforward and manageable equations to be obtainollutants atrazine, bentazone, carbamazepine, diclofenac, diuron and ibuprofen. Extension to additional compounds requires translation of the traditional, polychromatic language into the EMW one. Hopefully, this contribution will introduce a new paradigm in the mathematical description of photochemical reactions in environmental waters. It could also become a new and simple way to treat multi-wavelength systems in general photochemistry studies, thereby completely changing the way multi-wavelength problems are dealt with.In recent years, fluidized-bed Fenton (FBR-Fenton) process has gained more attention in treating recalcitrant industrial wastewater. FBR-Fenton combines the effectiveness of homogeneous Fenton and sludge reduction of heterogeneous Fenton. Comparing to other modified Fenton processes, FBR-Fenton has greater economical and scaling up potential. However, large consumption of Fenton reagents and strict pH control are still the bottlenecks hampering the full-scale application of FBR-Fenton. While prior reviews mainly focused on the operation and performance of FBR-Fenton process, the present study critically discussed the challenges and bottlenecks for its full-scale industrial application. This study also comprehensively reviewed the development strategies for tackling these drawbacks, mainly over the recent five years. Homogeneous FBR-Fenton, heterogeneous FBR-Fenton and heterogeneous FBR-photo-Fenton processes were classified for the first time according to their reaction mechanisms and system designs. T705 Important operational and design parameters affecting the cost-effectiveness of all FBR-Fenton technologies were reviewed, including the fundamentals, common practices and even innovative steps for enhancing the process performance. Up-to-date applications of FBR-Fenton technologies in recalcitrant wastewater/compounds treatment were also summarized, and it was found that upscaling of heterogeneous FBR-Fenton and heterogeneous FBR-photo-Fenton processes was still very challenging. Strategies to overcome the key technical limitations and enhance process cost-effectiveness were discussed in the future perspective part. Furthermore, modelling techniques such as computational fluid dynamics model and artificial neural network were suggested to be promising modelling techniques for speeding up the full-scale applications of FBR-Fenton technologies.Membrane fouling and ammonium transmembrane diffusion simultaneously pose great challenges in membrane-based pre-concentration of domestic wastewater for efficient subsequent resources recovery (i.e., energy and nutrients). Herein, amine-functionalized osmotic membranes were fabricated by optimizing the grafting pathway of polyamidoamine (PAMAM) dendrimer to mitigate fouling and ammonium transmembrane diffusion. Compared to the control membrane, the PAMAM-grafted membranes with abundant primary amine groups possessed substantially increased hydrophilicity and positive charges (i.e., protonated primary amines) and thus exhibited superior anti-fouling capability and ammonium selectivity. With further increasing the PAMAM grafting ratio, the membrane exhibited a steady enhancement in ammonium selectivity and eventually achieved an ultra-high ammonium rejection of 99.4%. Nevertheless, the anti-fouling capability of such ammonium ultra-selective membrane was weakened due to the suppression of the adverse impact of excessive positive charges over the beneficial effect of increased surface hydrophilicity. This in turn leads to a drop of ammonium rejection below 90% during domestic wastewater concentration. This study demonstrates that the membrane with a moderate primary amine loading could achieve the highest anti-fouling capability with only less than 10% flux decline and meanwhile maintain an excellent ammonium rejection above 94% during raw domestic wastewater concentration. This work provides theoretical guidance for fabricating simultaneously enhanced anti-fouling and ammonia-rejecting membranes.