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Developing sensors with high selectivity and sensitivity is of great significance for pesticide analysis in environmental assessment. Herein, a versatile three-way sensor array was designed for the detection of the pesticide atrazine, based on the integration of catalytic hairpin assembly (CHA) amplification and three-mode signal transducers. With atrazine, CHA was triggered to generate abundant G-quadruplex. The produced G-quadruplex hybrid could assemble with thioflavin T (TFT) or hemin to mimic enzyme and induce the fluorescence enhancement by TFT, or the colorimetric increase by the oxidized chromogenic substrate and the naked-eye color change by inhibiting the L-cysteine-mediated aggregation of gold nanoparticles. A distinctive three-mode array was successfully constructed with convenience, on-site accessibility and high sensitivity for enzyme-free practical analysis of atrazine. It is also effective and reliable for analyzing real samples including paddy water, paddy soil and polished rice. The detection limits for atrazine were as low as 7.4 pg/mL by colorimetric observation and 0.25 pg/mL by fluorescent detection. Furthermore, the array was exploited to monitor the residue, distribution and bioaccumulation of atrazine in maize and rice for food security and environmental assessment. Hence, this work presented a versatile example for sensitive and on-site all-in-one pesticide analysis arrays with multiple signal report modes.
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Atrazina , Produtos Agrícolas , DNA Catalítico , Quadruplex G , Atrazina/análise , DNA Catalítico/química , DNA Catalítico/metabolismo , Produtos Agrícolas/química , Aptâmeros de Nucleotídeos/química , Monitoramento Ambiental/métodos , Técnicas Biossensoriais/métodos , Oryza/química , Zea mays/química , Herbicidas/análise , Herbicidas/química , Praguicidas/análise , Praguicidas/química , Nanopartículas Metálicas/química , Ouro/química , Benzotiazóis/química , Limite de Detecção , Hemina/química , Poluentes Químicos da Água/análise , ColorimetriaRESUMO
The process of sorting light based on colors (photon energy) is a prerequisite in broadband optical systems, typically achieved in the form of guiding incoming signals through a sequence of spectral filters. The assembly of filters often leads to lengthy optical trains and consequently, large system footprints. In this work, we address this issue by proposing a flat color-sorting device comprising a diffraction grating and a dielectric Huygens' metasurface. Upon the incidence of a broadband beam, the grating disperses wavelengths to a continuous range of angles in accordance with the law of diffraction. The following metasurface with multiple paired Huygens' resonances corrects the dispersion and binds wavelengths to the corresponding waveband with a designated output angle. We demonstrate the sorting efficacy by designing a device with a color-sorting metasurface with two discrete dispersion-compensated outputs (10.8 ± 0.3 µm and 11.9 ± 0.3 µm), based on the proposed approach. The optimized metasurface possesses an overall transmittance exceeding 57% and reduces lateral dispersion by 90% at the output. The proposed color-sorting mechanism provides a solution that benefits the designing of metasurfaces for miniature multi-band systems.
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The denitrifying sulfur (S) conversion-associated enhanced biological phosphorus removal (DS-EBPR) process for treating saline wastewater is characterized by its unique microbial ecology that integrates carbon (C), nitrogen (N), phosphorus (P), and S biotransformation. However, operational instability arises due to the numerous parameters and intricates bacterial interactions. This study introduces a two-stage interpretable machine learning approach to predict S conversion-driven P removal efficiency and optimize DS-EBPR process. Stage one utilized the XGBoost regression model, achieving an R2 value of 0.948 for predicting sulfate reduction (SR) intensity from anaerobic parameters with feature engineering. Stage two involved the CatBoost classification and regression model integrating anoxic parameters with the predicted SR values for predicting P removal, reaching an accuracy of 94% and an R2 value of 0.93, respectively. This study identified key environmental factors, including SR intensity (20-45 mg S/L), influent P concentration (<9.0 mg P/L), mixed liquor volatile suspended solids (MLVSS)/mixed liquor suspended solids (MLSS) ratio (0.55-0.72), influent C/S ratio (0.5-1.0), anoxic reaction time (5-6 h), and MLSS concentration (>6.50 g/L). A user-friendly graphic interface was developed to facilitate easier optimization and control. This approach streamlines the determination of optimal conditions for enhancing P removal in the DS-EBPR process.
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Carbono , Aprendizado de Máquina , Nitrogênio , Fósforo , Enxofre , Águas Residuárias , Fósforo/metabolismo , Nitrogênio/metabolismo , Enxofre/metabolismo , Águas Residuárias/química , Carbono/metabolismo , Biotransformação , Ecossistema , Eliminação de Resíduos Líquidos/métodos , DesnitrificaçãoRESUMO
The rapid advancement of portable electronics has created enormous demand for compact optical imaging systems. Such systems often require folded optical systems with beam steering and shaping components to reduce sizes and minimize image aberration at the same time. In this study, we present a solution that utilizes an inverse-designed dielectric metasurface for arbitrary-angle image-relay with aberration correction. The metasurface phase response is optimized by a series of artificial neural networks to compensate for the severe aberrations in the deflected images and meet the requirements for device fabrication at the same time. We compare our results to the solutions found by the global optimization tool in Zemax OpticStudio and show that the proposed method can predict better point-spread functions and images with less distortion. Finally, we designed a metasurface to achieve the optimized phase profile.
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Electrochemical pretreatment (EPT) has shown to be superior in improving acidogenic co-fermentation (Co-AF) of waste activated sludge (WAS) and food waste (FW) for volatile fatty acids (VFAs). However, the influence of EPT electrode materials on the production of electrogenerated oxidants (such as singlet oxygen (1O2) and reactive chlorine species (RCS)), as well as their effects on properties of electrodes, the microbial community structure and functional enzymes remain unclear. Therefore, this study investigated the effects of various metal oxide coated electrodes (i.e., Ti/PbO2, Ti/Ta2O5-IrO2, Ti/SnO2-RuO2, and Ti/IrO2-RuO2) on EPT and subsequent Co-AF of WAS-FW. The results showed that EPT with Ti/PbO2, Ti/Ta2O5-IrO2, Ti/SnO2-RuO2 and Ti/IrO2-RuO2 electrodes generated 165.3-848.2 mg Cl2/L of RCS and 5.643 × 1011-3.311 × 1012 spins/mm3 of 1O2, which significantly enhanced the solubilization and biodegradability of WAS-FW by 106.4 %-233.6 % and 177.3 %-481.8 %, respectively. Especially with Ti/Ta2O5-IrO2 as the electrode material, an appropriate residual RCS (2.0-10.4 mg Cl2/L) remained in Co-AF step, resulted in hydrolytic and acidogenic bacteria (e.g., Prevotella_7, accounting for 78.9 %) gradually become dominant rather than methanogens (e.g., Methanolinea and Methanothrix) due to their different tolerance to residual RCS. Meanwhile, the functional gene abundances of hydrolytic and acidogenic enzymes increased, while the methanogenic enzymes deceased. Consequently, this reactor produced the highest VFAs up to 545.5 ± 36.0 mg COD/g VS, which was 101.8 % higher than that of the Control (without EPT). Finally, the economic analysis and confirmatory experiments further proved the benefits of WAS-FW Co-AF with EPT.
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Eletrodos , Ácidos Graxos Voláteis , Esgotos , Ácidos Graxos Voláteis/metabolismo , Esgotos/química , Cloro , Fermentação , Óxidos/química , Metais , Eliminação de Resíduos Líquidos/métodos , Perda e Desperdício de AlimentosRESUMO
Anaerobic fermentation (AF) has been identified as a promising method of transforming waste activated sludge (WAS) into high-value products (e.g., short-chain fatty acids (SCFAs)). This study developed thiosulfate/FeCl3 pre-treatment and investigated the effects of different thiosulfate/FeCl3 ratios (S:Fe = 3:1, 3:2, 1:1, 3:4 and 3:5) on SCFA production and sulfur transformation during the AF of WAS. At a S:Fe ratio of 1:1, the maximal SCFA yield (933.3 mg COD/L) and efficient H2S removal (96.5 %) were obtained. S:Fe ratios ≤ 1:1 not only benefited hydrolysis and acidification but largely mitigated H2S generation. These results were supported by the enriched acidogens and reduced sulfur-reducing bacteria (SRB). Molecular ecological network analysis further revealed that the keystone taxon (g_Saccharimonadales) was found in S:Fe = 1:1, together with reductions in associations among methanogens, acidogens and SRB. This work provides a strategy for enhancing high-value product recovery from WAS and minimising H2S emissions.
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Cloretos , Compostos Férricos , Microbiota , Esgotos , Fermentação , Esgotos/microbiologia , Anaerobiose , Tiossulfatos , Ácidos Graxos Voláteis , Concentração de Íons de HidrogênioRESUMO
Coastal regions, home to more than half of the global population and contributing over 50% to the global economy, possess vast renewable resources, such as seawater and solar energy. The effective utilization of these resources, through the seawater-cooled district cooling system (SWDCS), seawater toilet flushing (SWTF), and rooftop solar photovoltaic system (RTPV), has the potential to significantly reduce carbon emissions. However, implementing these technologies in different geographic contexts to achieve the desired carbon and economic outcomes at the city level lacks a clear roadmap. To address this challenge, we comprehensively analyzed 12 coastal megacities worldwide by integrating geospatial building data. Our study evaluated the potential energy savings, carbon mitigation, and levelized carbon abatement costs (LCACs) from a life cycle perspective. The results revealed that using seawater and solar energy within urban boundaries can reduce electricity consumption from 1 to 24% across these cities. The spatial distribution of the LCAC for seawater-based systems exhibited more variation compared to the RTPV. By applying specific LCAC thresholds ranging from 0 to 225 USD/tCO2e, all cities could achieve both carbon reductions and economic benefits. These thresholds resulted in up to 80 million tonnes of carbon emission reductions and 5 billion USD of economic benefits, respectively. Our study provides valuable insights into integrating renewable resource systems, enabling coastal cities to achieve carbon and economic advantages at the city scale simultaneously.
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Aparelho Sanitário , Energia Solar , Cidades , Carbono , Água do MarRESUMO
Zero-dimensional (0D) lead-free halide perovskites have lately received significant interest owing to their captivating broadband emissions. An in-depth understanding of the luminescence mechanism of self-trapped excitons (STEs) and realization of effective regulation of luminescence properties have become a major challenge in the research of lead-free metal halides. Herein, we have synthesized the Cs2ZnCl4 and Sb3+-doped Cs2ZnCl4 crystals and conducted a comprehensive investigation into their distinct electronic structures and optical characteristics. The findings from both experimental and theoretical investigations indicate that the tricolor luminescence in Cs2ZnCl4 and blue emission in Sb3+-doped Cs2ZnCl4 stem from intrinsic STEs, and the near-infrared emission originates from extrinsic STEs associated with the Sb3+ ion in Sb3+-doped Cs2ZnCl4. Sb3+ doping increases the quantum yield of Cs2ZnCl4 to a large extent. In addition, intersystem crossing, exciton self-trapping, and lattice relaxation are the main reasons for the large Stokes shift. The present study is expected to provide a novel perspective for researchers in comprehending the luminescent mechanism of STEs and advancing the utilization of 0D lead-free metal halides in optoelectronic applications.
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Resource recovery is a pivotal facet of waste activated sludge treatment, particularly within the framework of carbon neutrality and the circular economy. Polysaccharides are emerging as a valuable resource from waste activated sludge, and the choice of extraction method affects the properties of the polysaccharides, which is of utmost importance for subsequent application. This investigation examined the effects of six extraction methods (i.e., acidic, alkaline, ultrasonication, hot-water, microwave, and electric treatments) on the yield, chemical composition, structural characteristics, and bioactivities of polysaccharides extracted from sludge. For each extraction method, two operational parameters, namely the treatment time and strength (e.g., the acid and alkali concentration), were initially optimized in terms of the polysaccharide yield. The polysaccharide yield varied from 1.03 ± 0.12 % to 5.34 ± 0.10 % adopting the extraction methods under optimized conditions, and the alkaline extraction method had the highest yield of polysaccharides with a treatment time of 120 min and NaOH concentration of 1 %. At least one polysaccharide fraction was successfully purified from the crude polysaccharide of each extraction method. The compositions and structures of these fractions, including carbohydrate, protein, sulfate, uronic acid contents, and monosaccharide compositions, were determined. Carbohydrate was the dominant component, with the hot-water-2 fraction having the highest carbohydrate content (77.90 % ± 2.02 %). Monosaccharides in the polysaccharides were measured, with mannose, rhamnose, glucose, and xylose being found in all fractions, whereas ribose was exclusively found in the acid-1 fraction. The molecular weights of these fractions ranged between 1.60 × 104 Da and 7.11 × 106 Da. Furthermore, the bioactivities of the polysaccharides, encompassing five anti-oxidant and three anti-coagulant properties, were assessed, with the ultrasonication-1 fraction having superior performance in seven of the assays. Finally, the association among the fractions in terms of composition and bioactivity was assessed adopting cluster analysis and regression methods. The findings underscore the effect of the extraction method on the properties of polysaccharides extracted from sludge, thereby providing valuable insights for the prospective applications of polysaccharides.
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Antioxidantes , Esgotos , Antioxidantes/análise , Peso Molecular , Polissacarídeos/química , Monossacarídeos/análise , Monossacarídeos/química , Água/químicaRESUMO
Plastics are indispensable in modern society but also pose a persistent threat to the environment. In particular, microplastics (MPs) have a substantial environmental impact on ecosystems. Municipal solid waste landfill leachates are a source of MPs, but leakage of MPs from leachates has only been reported in a few studies. As a modern city, Hong Kong has a remarkably high population density and a massive plastic waste generation. However, it depends on conventional landfilling for plastic waste management and traditional thermal ammonia stripping for leachate treatment. Yet, the MP leakage from landfill leachates in Hong Kong has not been disclosed. This is the first study that aimed to identify, quantify, and characterise MPs in raw and treated leachates, respectively, from major landfill sites in Hong Kong. The concentrations of MPs varied from 49.0 ± 24.3 to 507.6 ± 37.3 items/L among the raw leachate samples, and a potential correlation was found between the concentration of MPs in the raw leachate sample from a given landfill site and the annual leachate generation of the site. Most MPs were 100-500 µm fragments or filaments and were transparent or yellow. Regarding the polymeric materials among the identified MPs, poly(ethylene terephthalate) and polyethylene were the most abundant types, comprising 45.30% and 21.37% of MPs, respectively. Interestingly, leachates treated by ammonia stripping contained higher concentrations of MPs than raw leachate samples, which demonstrated that the traditional treatment process may not be sufficient regarding the removal of emerging pollutants, such as MPs. Overall, our findings provide a more comprehensive picture of the pollution of MPs in landfill leachates in Hong Kong and highlight the urgent need for adopting the consideration of MPs into the conventional mindset of waste management systems in Hong Kong.
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Eliminação de Resíduos , Poluentes Químicos da Água , Resíduos Sólidos/análise , Microplásticos , Plásticos , Poluentes Químicos da Água/análise , Hong Kong , Amônia , Ecossistema , Instalações de Eliminação de Resíduos , ChinaRESUMO
Dark-field microscopy (DFM) is a powerful label-free and high-contrast imaging technique due to its ability to reveal features of transparent specimens with inhomogeneities. However, owing to the Abbe's diffraction limit, fine structures at sub-wavelength scale are difficult to resolve. In this work, we report a single image super resolution DFM scheme using a convolutional neural network (CNN). A U-net based CNN is trained with a dataset which is numerically simulated based on the forward physical model of the DFM. The forward physical model described by the parameters of the imaging setup connects the object ground truths and dark field images. With the trained network, we demonstrate super resolution dark field imaging of various test samples with twice resolution improvement. Our technique illustrates a promising deep learning approach to double the resolution of DFM without any hardware modification.
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The sulfate reagent plays a crucial role as an electron acceptor in the sulfidogenic biodegradation process of the BSP assay for assessing the anaerobic biodegradability of organic substrates. However, the specific role and influence of the monovalent cations (sodium or potassium) in the sulfate reagent remain unknown. To address this gap, a series of batch assays were conducted to investigate the mechanistic effects of Na+ and K+. The results demonstrated that sodium has inhibitory effects on BSP assay when the dosage exceeds 8500 mg/L, whereas no adverse effects were observed in the potassium tests (ranging from 1800 to 14400 mg/L). In fact, the presence of K+ even enhanced the anaerobic biodegradability of organic substrates, and the underlying mechanisms were explored. These findings confirm the influence of cations in the BSP assay for biodegradability assessment and also provide guidance on sulfate dosage strategies for BSP assay application in anaerobic biotechnologies.
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Esgotos , Sulfetos , Cátions Monovalentes , Sulfetos/metabolismo , Sulfatos/metabolismo , Sódio , PotássioRESUMO
Two limiting factors of microbial electrochemical denitrification (MED) are the abundance and efficiency of the functional microorganisms. To supply these microorganisms, MED systems are inoculated with denitrifying sludge, but such method has much room for improvement. This study compared MED inoculated with autotrophic denitrifying inoculum (ADI) versus with heterotrophic denitrifying inoculum (HDI). ADI exhibited electroactivity for 50% less of timethan HDI. The denitrification efficiency of the ADI biocathode was42% higherthan that of the HDI biocathode. The HDI biocathode had high levels of polysaccharides while the ADI biocathode was rich in proteins, suggesting that two biocathodes may achieveMED but via differentpathways. Microbial communities of two biocathodes indicated MED of HDI biocathode may rely on interspecies electron transfer, whereas sulfur bacteria of ADI biocathode take electrons directly from the cathode to achieve MED. Utilizing autotrophic sulfur-oxidizing denitrifiers, this study offers a strategy for enhancing MED.
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Desnitrificação , Nitratos , Nitratos/metabolismo , Bactérias/metabolismo , Processos Autotróficos , Reatores Biológicos/microbiologia , Enxofre/metabolismo , Nitrogênio/metabolismoRESUMO
This study proposes the Sulphate reduction, mixed sulphide- and thiosulphate-driven Autotrophic denitrification, Nitrification, and Anammox integrated (SANIA) process for sustainable treatment of mainstream wastewater after organics capture. Three moving-bed biofilm reactors (MBBRs) were applied for developing sulphate reduction (SR), mixed sulphide- and thiosulphate-driven partial denitrification and Anammox (MSPDA), and NItrification (N), respectively. Typical mainstream wastewater after organics capture (e.g., chemically enhanced primary treatment, CEPT) was synthesized with chemical oxygen demand (COD) of 110 mg/L, sulphate of 50 mg S/L, ammonium of 30 mgN/L. The feasibility of SANIA was investigated with mimic nitrifying effluent supplied in MSPDA-MBBR (Period I), followed by the examination of the applicability of SANIA process with N-MBBR integrated (Period II), under moderate temperatures (25-27 â). In Period I, SANIA process was established with both SR- and MSPDA-MBBR continuously operated for over 300 days (no Anammox biomass inoculation). Specifically, in MSPDA-MBBR, high rates of denitratation (2.7 gN/(m2·d)) and Anammox (2.8 gN/(m2·d)) were achieved with Anammox contributing to 81 % of the total inorganic nitrogen removal. In Period II, the integrated SANIA system was continuously operated for over 130 days, achieving up to 90 % of COD, 93 % of ammonium, and 61 % of total inorganic nitrogen (TIN) removal, with effluent concentrations lower than 10 mg COD/L, 3 mg NH4+-N/L, and 13 mg TIN-N/L. The implementation of SANIA can ultimately reduce 75 % and 40 % of organics and aeration energy for biological nitrogen removal. Considering the combination of SANIA with CEPT for carbon capture and sludge digestion/incineration for energy recovery, the new integrated wastewater technology can be a promising strategy for sustainable wastewater treatment.
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Compostos de Amônio , Purificação da Água , Nitrificação , Águas Residuárias , Desnitrificação , Tiossulfatos , Biofilmes , Oxidação Anaeróbia da Amônia , Reatores Biológicos , Oxirredução , Esgotos , NitrogênioRESUMO
Since the discovery of nanobubbles (NBs) in 1994, NBs have been attracting growing attention for their fascinating properties and have been studied for application in various environmental fields, including water and wastewater treatment. However, despite the intensive research efforts on NBs' fundamental properties, especially in the past five years, controversies and disagreements in the published literature have hindered their practical implementation. So far, reviews of NB research have mainly focused on NBs' role in specific treatment processes or general applications, highlighting proof-of-concept and success stories primarily at the laboratory scale. As such, there lacks a rigorous review that authenticates NBs' potential beyond the bench scale. This review aims to provide a comprehensive and up-to-date analysis of the recent progress in NB research in the field of water and wastewater treatment at different scales, along with identifying and discussing the challenges and prospects of the technology. Herein, we systematically analyze (1) the fundamental properties of NBs and their relevancy to water treatment processes, (2) recent advances in NB applications for various treatment processes beyond the lab scale, including over 20 pilot and full-scale case studies, (3) a preliminary economic consideration of NB-integrated treatment processes (the case of NB-flotation), and (4) existing controversies in NBs research and the outlook for future research. This review is organized with the aim to provide readers with a step-by-step understanding of the subject matter while highlighting key insights as well as knowledge gaps requiring research to advance the use of NBs in the wastewater treatment industry.
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Food waste (FW) being a major solid waste component and of degradable nature is the most challenging to manage and mitigate greenhouse gas emissions (GHEs). Policymakers seek innovative approaches to achieve net zero objectives and recover resources from the FW which requires a comparative and holistic investigation of contemporary treatment methods. This study assessed the lifecycle of six alternative scenarios for reducing net GHEs and energy use potential from FW management in a metropolis, taking Hong Kong as a reference. In both impact categories, the business-as-usual (landfilling) was the worst-case scenario. The combined anaerobic digestion and composting (ADC) technique was ranked best in the global warming impact but was more energy intensive than anaerobic digestion with sludge landfilling (ADL). Incineration ranked second in net GHEs but less favourable for energy recovery from FW alone. The proposed integration of FW and biological wastewater treatment represented an enticing alternative. Integration by co-disposal and treatment with wastewater (CoDT-WW) performed above average in both categories, while anaerobic co-digestion with sewage sludge (AnCoD-SS) ranked fourth. The sensitivity analysis further identified critical parameters inherent to individual scenarios along with biogenic carbon emission and sequestration, revealing their significance on the magnitude of GHEs and scenarios' ranking. Capacity assessment of the studied treatment facilities showed a FW diversion potential of â¼60% while reducing the net GHEs by â¼70% compared to the base-case, indicating potential of net zero carbon emissions and energy footprint by increasing treatment capacity. From this study, policymakers can gain insights and guidelines for low-carbon urban infrastructure development worldwide.
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Eliminação de Resíduos , Gerenciamento de Resíduos , Eliminação de Resíduos/métodos , Esgotos , Alimentos , Gerenciamento de Resíduos/métodos , Resíduos Sólidos , Águas Residuárias , CarbonoRESUMO
Sulfur-driven autotrophic denitrification (SdAD) is a biological process that can remove nitrate from low carbon/nitrogen (C/N) ratio wastewater. Although this process has been intensively researched, the mechanism whereby its intermediates (i.e., elemental sulfur and nitrite ions) are generated and accumulated remains elusive. Existing mathematical models developed for SdAD cannot accurately predict the intermediates in SdAD because of the incomplete knowledge of process kinetic resulting from changes in the environmental conditions and electron competition during SdAD. To address this limitation, we proposed a novel serial hybrid model structure based on a physics-informed neural network (PINN) to capture the dynamics of the process kinetics and predict the substrate concentrations in SdAD. In this study, we evaluated the model through numerical experiments and applied it to real case studies involving batch and continuous-flow reactor scenarios. By leveraging the PINN approach, the hybrid model yielded accurate predictions at both the state (i.e. substrate concentration) and kinetic levels in the numerical experiments and performed better than both mechanistic and purely data-driven models in the case studies. Furthermore, we used the trained hybrid model to design control strategies for SdAD and a novel integrated process involving SdAD and anammox for energy-efficient nitrogen removal. Finally, we discuss the advantages and application scope of the PINN-based hybrid model.
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Reatores Biológicos , Desnitrificação , Cinética , Enxofre , Nitratos , Processos Autotróficos , Nitrogênio , FísicaRESUMO
Pharmaceuticals have been considered a priority group of emerging micropollutants in source waters in recent years, while their role in the formation and toxicity of disinfection byproducts (DBPs) during chlorine disinfection remains largely unclear. In this study, the contributions of natural organic matter (NOM) and pharmaceuticals (a mixture of ten representative pharmaceuticals) to the overall DBP formation and toxicity during drinking water chlorination were investigated. By innovatively "normalizing" chlorine exposure and constructing a kinetic model, we were able to differentiate and evaluate the contributions of NOM and pharmaceuticals to the total organic halogen (TOX) formation for source waters that contained different levels of pharmaceuticals. It was found that at a chlorine contact time of 1.0 h, NOM (2 mg/L as C) and pharmaceuticals (total 0.0062-0.31 mg/L as C) contributed 79.8-99.5% and 0.5-20.2%, respectively, of TOX. The toxicity test results showed that the chlorination remarkably increased the toxicity of the pharmaceutical mixture by converting the parent compounds into more toxic pharmaceutical-derived DBPs, and these DBPs might contribute significantly to the overall developmental toxicity of chlorinated waters. This study highlights the non-negligible role of pharmaceuticals in the formation and toxicity of overall DBPs in chlorinated drinking water.
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Desinfetantes , Água Potável , Poluentes Químicos da Água , Purificação da Água , Halogenação , Desinfetantes/toxicidade , Cloro , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Desinfecção , Preparações FarmacêuticasRESUMO
Water and energy are critical components of urban metabolism. However, climate change-induced water scarcity and elevated temperatures pose a significant threat to the adequate supply of essential human services, including sanitation and space cooling, particularly in coastal cities where over 40% of the population resides. The water-energy nexus of sanitation and space cooling is crucial for promoting sustainability and resilience in coastal cities. For decades, Hong Kong has demonstrated the effectiveness of using seawater for toilet flushing and district cooling to save water and energy, which could serve as a potential solution for other coastal cities worldwide. Seawater is a superior alternative to other sources of toilet flushing water due to its abundant availability, easy detection of cross-contamination, and lower treatment costs. Furthermore, saline wastewater treatment requires fewer materials and energy inputs and produces less sludge. Using seawater for district cooling also saves energy without exacerbating water stress. However, there is a lack of comprehensive insights from Hong Kong on how seawater use can be adopted by other coastal cities to promote sustainable development. A successful introduction of seawater into coastal cities requires a holistic water-energy management framework that provides technical and policy-level guidance. We developed such a framework that follows four sustainability principles, namely customized solutions, efficient resource allocation, comprehensive evaluation, and optimized tradeoffs. These principles are designed into contextualized location analysis, urban spatial analysis, integrated sustainability assessment, and nexus analysis. The results of these analyses can aid decision-making regarding the technical and policy aspects of seawater uses in sanitation and space cooling to maximize the positive impacts on sustainable development. Breaking barriers between sectors and encouraging inter-municipal cooperation between sectors are critical to the successful use of seawater. By adopting this framework and promoting collaboration across different sectors, coastal cities can enhance their sustainability and resilience, providing a better quality of life for their citizens.
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Pelvic ectopic kidney is a congenital anomaly with a higher probability of hydronephrosis than a normal kidney. Few studies have reported cases of pelvic ectopic kidney with hydronephrosis in adults treated with robot-assisted laparoscopic pyeloplasty (RALP). We performed RALP on a 22-year-old male and he recovered well after the procedure. The patient's pain disappeared after surgery. No complications occurred during the perioperative period and had a rapid postoperative recovery.