Sustained oxidation of Tea-Fe(III)/H2O2 simultaneously achieves sludge reduction and carbamazepine removal: The crucial role of EPS regulation

Establishing an economic and sustained Fenton oxidation system to enhance sludge dewaterability and carbamazepine (CBZ) removal rate is a crucial path to simultaneously achieve sludge reduction and harmless. Leveraging the principles akin to "tea making", we harnessed tea waste to continually release tea polyphenols (TP), thus effectively maintaining high level of oxidation efficiency through the sustained Fenton reaction. The results illustrated that the incorporation of tea waste yielded more favorable outcomes in terms of water content reduction and CBZ removal compared to direct TP addition within the Fe(III)/hydrogen peroxide (H2O2) system. Concomitantly, this process mainly generated hydroxyl radical (•OH) via three oxidation pathways, effectively altering the properties of extracellular polymeric substances (EPS) and promoting the degradation of CBZ from the sludge mixture. The interval addition of Fe(III) and H2O2 heightened extracellular oxidation efficacy, promoting the desorption and removal of CBZ. The degradation of EPS prompted the transformation of bound water to free water, while the formation of larger channels drove the discharge of water. This work achieved the concept of treating waste with waste through using tea waste to treat sludge, meanwhile, can provide ideas for subsequent sludge harmless disposal.

Magnetic nanoparticle loading and application of weak magnetic field to reconstruct the cake layer of coagulation-ultrafiltration process to achieve efficient antifouling: Performance and mechanism analysis

Abandoning the costly development of new membrane materials and instead directly remodeling the naturally occurring cake layer constitutes a dynamic, low-cost, long-lasting, and proactive strategy to "fight fouling with fouling". Several optimization strategies, including coagulation/modified magnetic seed loading and applying a weak magnetic force (0.01T) at the ultrafiltration end, improved the anti-fouling, retention, and sieving performances of conventional ultrafiltration process during the treatment of source water having complex natural organic matter (NOMs) and small molecule micropollutants. Two modified magnetic seeds we prepared were composite nano-seed particles (Fe3O4@SiO2-NH2 (FS) and Fe3O4@SiO2@PAMAM-NH2 (FSP)). Aim of the study was to regulate the formation of cake layer via comprehensive testing of the antifouling properties of optimized processes and related mechanistic studies. It was found to be essential to enhance the interception of xanthate and tryptophan proteins in the cake layer for improving the anti-fouling performance based on the correlation and redundancy analyses, while the use of modified magnetic seeds and magnetic field showed a significant positive impact on water production. Blockage modeling demonstrated the ability to form a mature cake layer during the initial filtration stage swiftly. This mitigated the risk of irreversible fouling caused by pore blockage during the early stage of coagulation-ultrafiltration. Morphologically, the reconstructed cake layer exhibited elevated surface porosity, an internal cavity channel structure, and enhanced roughness that can promote increased water flux and retention of water impurities. These optimized the maturity of the cake layer in both time and space. Density Functional Theory (DFT), Extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, and Modified Extended Derjaguin-Landau-Verwey-Overbeek (MDLVO) calculations indicated aggregation behavior of matter on the cake layer to be enhanced effectively due to magnetic seed loading. This is mainly due to the strengthening of polar interactions, including hydrogen bonding, π-π* conjugation, etc., which can happen between the cake layer loaded with FSP and the organic matter. Under the influence of a magnetic field, magnetic force energy (VMF) significantly impacts the system by eliminating energy barriers. This research will provide innovative strategies for effectively purifying intricate source water through ultrafiltration while controlling membrane fouling.

Effects of biochar-derived dissolved organic matter on the gut microbiomes and metabolomics in earthworm Eisenia fetida

The ecological risks of biochar-derived dissolved organic matter (DOM) to soil invertebrates at different organismal levels remains limited. This study comprehensively explored the ecological risks of biochar-derived DOM on earthworm gut through assessments of enzyme activity response, histopathology, gut microbiomes, and metabolomics. Results demonstrated that DOM disturbed the digestive enzymes in earthworm, especially for 10% DOM300 groups. The integrated biomarker response v2 (IBRv2) indicated that the perturbation of earthworm digestive enzymes induced by DOM was both time-dependent and dose-dependent. Pathological observations revealed that 10% DOM300 damaged intestinal epithelium and digestive lumen of earthworms. The significant damage and injury to earthworms caused by DOM300 due to its higher concentrations of heavy metal ions and organic substrates (e.g., toluene, hexane, butanamide, and hexanamide) compared to DOM500 and DOM700. Analysis of 16S rRNA from the gut microbiota showed a significant decrease in genera (Verminephrobacter, Bacillus, and Microbacteriaceae) associated with inflammation, disease, and detoxification processes. Furthermore, 10% DOM300 caused the abnormality of metabolites, such as glutamate, fumaric acid, pyruvate, and citric acid, which were involved in energy metabolism, These findings contributed to improve our understanding of the toxic mechanism of biochar DOM from multiple perspectives.

Construction of n-type homogeneous to improve interfacial carrier transfer for enhanced photoelectrocatalytic hydrolysis

Photoelectrocatalyzed hydrogen production plays an important role in the path to carbon neutrality. The construction of heterojunctions provides an ideal example of an oxygen precipitation reaction. In this work, the performance of the n-n type heterojunction CeBTC@FeBTC/NIF in the photoelectronically coupled catalytic oxygen evolution reaction (OER) reaction is presented. The efficient transfer of carriers between components enhances the catalytic activity. Besides, the construction of heterojunctions optimizes the energy level structure and increases the absorption of light, and the microstructure forms holes with a blackbody effect that also enhances light absorption. Consequently, CeBTC@FeBTC/NIF has excellent photoelectric coupling catalytic properties and requires an overpotential of only 300 mV to drive a current density of 100 mA cm-2 under illumination. More importantly, the n-n heterojunction was found to be effective in enhancing charge and photogenerated electron migration by examining the carrier density of each component and carrier diffusion at the interface.

Catalytic pyrolysis of liquor-industry waste: Product and mechanism analysis

The effects of three catalysts, namely Ni/γ-Al2O3, Fe/γ-Al2O3, and Mg/γ-Al2O3, on the three-phase products of liquor-industry waste pyrolysis were investigated in this study. Results indicated that the catalytic performance of Ni/γ-Al2O3 outperformed those of Fe/γ-Al2O3 and Mg/γ-Al2O3 significantly. The application of Ni/γ-Al2O3 facilitated the reformation of pyrolysis volatiles, leading to increased yields of H2 (174.1 mL/g), CH4 (80.7 mL/g), and CO (88.2 mL/g) by 980.00 %, 133.24 %, and 83.37 %, respectively. compared to catalyst-free conditions. The Ni/γ-Al2O3 also increased the low-level calorific value of biogas by 109.3 % compared to that under non-catalyst conditions. Moreover, Ni/γ-Al2O3 enhanced the relative concentrations of hydrocarbons in tar by 23.15 % while reducing the relative concentrations of O-species by 15.73 % compared to catalyst-free conditions through induced deoxygenation, decarboxylation, decarbonylation reactions as well as efficient steam reforming processes for tar and syngas upgrading purposes. Thus, incorporating Ni/γ-Al2O3 into the pyrolysis process represents a renewable approach for waste-to-energy conversion.

Fe-doping and oxygen vacancy achieved by electrochemical activation and precipitation/dissolution equilibrium in NiOOH for oxygen evolution reaction

The poor conductivities and instabilities of accessible nickel oxyhydroxides hinder their use as oxygen evolution reaction (OER) electrocatalysts. Herein, we constructed Fe-NiOOH-OV-600, an Fe-doped nickel oxide hydroxide with abundant oxygen vacancies supported on nickel foam (NF), using a hydrothermal method and an electrochemical activation strategy involving 600 cycles of cyclic voltammetry, assisted by the precipitation/dissolution equilibrium of ferrous sulfide (FeS) in the electrolyte. This two-step method endows the catalyst with abundant Fe-containing active sites while maintaining the ordered structure of nickel oxide hydroxide (NiOOH). Characterization and density functional theory (DFT) calculations revealed that synergy between trace amounts of the Fe dopant and the oxygen vacancies not only promotes the generation of reconstructed active layers but also optimizes the electronic structure and adsorption capacity of the active sites. Consequently, the as-prepared Fe-NiOOH-OV-600 delivered large current densities of 100 and 1000 mA cm-2 for the OER at overpotentials of only 253 and 333 mV in 1 mol/L KOH. Moreover, the catalyst is stable for at least 100 h at 500 mA cm-2. This work provides insight into the design of efficient transition-metal-based electrocatalysts for the OER.

Biomolecular insights into the inhibition of heavy metals on reductive dechlorination of 2,4,6-trichlorophenol in Pseudomonas sp. CP-1

Influences of heavy metal exposure to the organohalide respiration process and the related molecular mechanism remain poorly understood. In this study, a non-obligate organohalide respiring bacterium, Pseudomonas sp. strain CP-1, was isolated and its molecular response to the five types of commonly existed heavy metal ions were thoroughly investigated. All types of heavy metal ions posed inhibitory effects on 2,4,6-trichlorophenol dechlorination activity and cell growth with the varied degree. Exposure to Cu (II) showed the most serious inhibitive effects on dechlorination even at the lowest concentration of 0.05 mg/L, while the inhibition by As (V) was the least with the removal kinetic constant k decreased to 0.05 under 50 mg/L. Further, multi-omics analysis found compared with Cu (II), As (V) exposure led to the insignificant downregulation of a variety of biosynthesis processes, which would be one possible account for the less inhibited activity. More importantly, the inhibited mechanisms on the organohalide respiration catabolism of strain CP-1 were firstly revealed. Cu (II) stress severely downregulated NADH generation during TCA cycle and electron donation of organohalide respiration process, which might decrease the reducing power required for organohalide respiration. While both Cu (II) and As (Ⅴ) inhibited substrate level phosphorylation during TCA cycle, as well as electron transfer and ATP generation during organohalide respiration. Meanwhile, CprA-2 was confirmed as the responsible reductive dehalogenase in charge of 2,4,6-TCP dechlorination, and transcriptional and proteomic studies confirmed the directly inhibited gene transcription and expression of CprA-2. The in-depth reveal of inhibitory effects and mechanism gave theoretical supports for alleviating heavy metal inhibition on organohalide respiration activity in groundwater co-contaminated with organohalides and heavy metals.

Systematic assessment of the ecotoxicological effects and mechanisms of biochar-derived dissolved organic matter (DOM) on the earthworm Eisenia fetida

Biochar-derived dissolved organic matter (DOM) contains toxic substances that are first released into the soil after biochar application. However, the ecological risks of biochar-derived DOM on soil invertebrate earthworms are unclear. Therefore, this study investigated the ecological risks and toxic mechanisms of sewage sludge biochar (SSB)-derived DOM on the earthworm Eisenia fetida (E. fetida) via microcosm experiments. DOM exposure induced earthworm death, growth inhibition, and cocoon decline. Moreover, DOM, especially the 10% DOM300 (derived from SSB prepared at 300 °C) treatments, disrupted the antioxidant defense response and lysosomal stability in earthworms. Integrated biomarker response v2 (IBRv2) analysis was performed to assess the comprehensive toxicity of DOM in E. fetida, and the results revealed that DOM300 might exert more hazardous effects on earthworms than DOM500 (prepared at 500 °C) and DOM700 (prepared at 700 °C), as revealed by increases in the IBRv2 value of 3.48-18.21. Transcriptome analysis revealed that 10% DOM300 exposure significantly disrupted carbohydrate and protein digestion and absorption and induced endocrine disorder. Interestingly, 10% DOM300 exposure also significantly downregulated the expression of genes involved in signaling pathways, e.g., the P13K-AKT, cGMP-PKG, and ErbB signaling pathways, which are related to cell growth, survival, and metabolism, suggesting that DOM300 might induce neurotoxicity in E. fetida. Altogether, these results may contribute to a better understanding of the toxicity and defense mechanisms of biochar-derived DOM on earthworms, especially during long-term applications, and thus provide guidelines for using biochar as a soil amendment.

Preparation of Surface-Active Hyperbranched-Polymer-Encapsulated Nanometal as a Highly Efficient Cracking Catalyst for In Situ Combustion of Heavy Oil

In situ combustion of heavy oil is currently the most suitable thermal method that meets energy consumption and carbon dioxide emission requirements for heavy oil recovery. The combustion catalyst needs to perform multiple roles for application; it should be capable of catalyzing heavy oil combustion at high temperatures, as well as be able to migrate in the geological formation for injection. In this work, a hyperbranched polymer composite nanometal fluid was used as the injection vector for a heavy oil in situ combustion catalyst, which enabled the catalyst to rapidly migrate to the surface of the oil phase in porous media and promoted heavy oil cracking deposition at high temperatures. Platinum (Pt) nanoparticles encapsulated with cetyl-hyperbranched poly(amide-amine) (CPAMAM), with high interfacial activity, were synthesized by a facile phase-transfer method; the resulting material is called Pt@CPAMAM. Pt@CPAMAM has good dispersion, and as an aqueous solution, it can reduce the interfacial tension between heavy oil and water. As a catalyst, it can improve the conversion rate during the pyrolysis of heavy oil in a nitrogen atmosphere. The catalyst structure designed in this study is closer to that exhibited in practical geological formation applications, making it a potential method for preparing catalysts for use in heavy oil in situ combustion to resolve the problem of catalyst migration in the geological formation.

Superior performance of novel chitosan-based flocculants in decolorization of anionic dyes: Responses of flocculation performance to flocculant molecular structures and hydrophobicity and flocculation mechanism

To achieve economical and efficient decolorization, two novel flocculants, weakly hydrophobic comb-like chitosan-graft-poly (N, N-Dimethylacrylamide) (CSPD) and strongly hydrophobic chain-like chitosan-graft-L-Cyclohexylglycine (CSLC) were synthesized in this study. To assess the effectiveness and application of CSPD and CSLC, the impacts of factors, including flocculant dosages, initial pH, initial dye concentrations, co-existing inorganic ions and turbidities, on the decolorization performance were explored. The results suggested that the optimum decolorizing efficiencies of the five anionic dyes ranged from 83.17% to 99.40%. Moreover, for accurately controlling flocculation performance, the responses to flocculant molecular structures and hydrophobicity in flocculation using CSPD and CSLC were studied. The Comb-like structure gives CSPD a wider dosage range for effective decolorization and better efficiencies with large molecule dyes under weak alkaline conditions. The strong hydrophobicity makes CSLC more effective in decolorization and more suitable for removing small molecule dyes under weak alkaline conditions. Meanwhile, the responses of removal efficiency and floc size to flocculant hydrophobicity are more sensitive. Mechanism studies revealed that charge neutralization, hydrogen bonding and hydrophobic association worked together in the decolorization of CSPD and CSLC. This study has provided meaningful guidance for developing flocculants in the treatment of diverse printing and dyeing wastewater.

Novel three-dimensional Ti3C2-MXene embedded zirconium alginate aerogel adsorbent for efficient phosphate removal in water

Excessive phosphorus in water causes environmental security problems like eutrophication. Advanced two-dimensional material MXene has attracted raising attention in aquatic adsorption, while lack of selectivity and difficult recovery limit its application in phosphate removal. In this study, Ti₃C₂-MXene embedded zirconium-crosslinked SA (MX-ZrSA) beads were synthesized and their phosphate adsorption performance under different conditions was assessed. Investigations using SEM/EDS, XRD, BET, TGA and contact angle meter reveal that the addition of Ti₃C₂-MXene enhanced the thermal stability, mechanical strength, hydrophilicity, and formed loose network-like mesoporous inner structure with large surface area. The theoretical maximum adsorption capacity was 492.55 mg P/g and was well fitted by Freundlich and optimized Langmuir models. The Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analysis showed that chemisorption was involved, and the formation of Zr-O-P and Ti-O-P complexes accounted for high selectivity and affinity to phosphate. The adsorption experiments in real waters and lab-scale continuous flow Anaerobic-Anoxic-Oxic reactor further indicated the application potential of MX-ZrSA beads. Our study will provide insight into MXene and SA aerogel synergistic adsorption of aquatic contaminants and help with the removal and recovery of finite phosphorus resource.

[Research progress of radiomics in the evaluation of microvascular invasion in hepatocellular carcinoma]

Microvascular invasion (MVI) is an independent predictor of early recurrence and poor prognosis following hepatocellular carcinoma (HCC) resection and transplantation. As a novel non-invasive diagnostic tool, radiomics can extract the quantitative imaging features of tumors and peritumoral tissues with high throughput, providing more information on tumor heterogeneity than conventional and functional imaging of visual analysis and having a good application prospect in predicting the presence of MVI in HCC patients, thereby improving the accuracy of HCC diagnosis and prognosis. The value of the multimodal radiomics method based on various imaging methods in evaluating the possibility of MVI in HCC patients is elucidated here in combination with the latest research progress.

Highly selective electrosynthesis of H2O2 by N, O co-doped graphite nanosheets for efficient electro-Fenton degradation of p-nitrophenol

The activity and selectivity of the cathode towards electrosynthesis of H₂O₂ are critical for electro-Fenton process. Herein, nickel-foam modified with N, O co-doped graphite nanosheets (NO-GNSs/Ni-F) was developed as a cathode for highly efficient and selective electrosynthesis of H₂O₂. Expectedly, the accumulation of H₂O₂ at pH= 3 reached 494.2 mg L^-1 h^-1, with the selectivity toward H₂O₂ generation reaching 93.0%. The synergistic effect of different oxygen-containing functional groups and N species on the performance and selectivity of H₂O₂ electrosynthesis was investigated by density functional theory calculations, and the combination of epoxy and graphitic N (EP + N) was identified as the most favorable configuration with the lowest theoretical overpotential for H₂O₂ generation. Moreover, NO-GNSs/Ni-F was applied in the electro-Fenton process for p-nitrophenol degradation, resulting in 100% removal within 15 min with the kinetic rate constant of 0.446 min^-1 and 97.6% mineralization within 6 h. The efficient removal was mainly attributed to the generation of bulk ·OH. Furthermore, NO-GNSs/Ni-F exhibited excellent stability. This work provides a workable option for the enhancement of H₂O₂ accumulation and the efficient degradation of pollutants in electro-Fenton system.

Hydrothermal pretreatment and compound microbial agents promoting high-quality kitchen waste compost: Superior humification degree and reduction of odour

Present study investigated the effects of hydrothermal pretreatment (HTP) and addition of compound microbial agent (CMA) on humification, odour generation and metabolism functions of bacterial communities during composting of kitchen waste (KW). Surprisingly, HTP and CMA addition treatment could promote the humification of compost and the control of odour units in contrast to the control (without HTP and CMA addition). The humic acid to fulvic acid ratio of end compost increase by 187.30 %, while humification index (HIX) increased by 18.87 %. 3D-EEM fluorescence spectroscopy of dissolved organic matter (DOM) demonstrated that it facilitated the synthesis of humified compounds and the decomposition of biodegradable compounds. Moreover, the SUVA₂₅₄, SUVA₂₈₀ and E₂₅₃/E₂₀₃ increased by 118.6 %, 115.25 % and 42.11 % after HTP and CMA addition indicating an increase in aromatic carbon abundance. VFAs had the higher degradation rate (84.91 %) than other treatments (57.46-77.72 %). Meanwhile, the main contributor to the malodorous odour was isovaleric acid, followed by butyric acid and acetic acid during composting. Mantel test indicated that the humification degree was significantly influenced by environmental parameters (temperature, pH, etc.) and metabolic products (HA, DOC and VFAs). Metagenomic analysis indicated that the biodegradation processes at the thermophilic stage were controlled mainly through genes involved in microbial metabolism. HTP and CMA addition was an eco-friendly and efficient strategy to reduce odour emission and improve the compost quality.

Cathode potential regulates the microbiome assembly and function in electrostimulated bio- dechlorination system

Mechanism of microbiome assembly and function driven by cathode potential in electro-stimulated microbial reductive dechlorination system remain poorly understood. Here, core microbiome structure, interaction, function and assembly regulating by cathode potential were investigated in a 2,4,6-trichlorophenol bio-dechlorination system. The highest dechlorination rate (24.30 μM/d) was observed under - 0.36 V with phenol as a major end metabolite, while, lower (-0.56 V) or higher (0.04 V or -0.16 V) potentials resulted in 1.3-3.8 times decreased of dechlorination kinetic constant. The lower the cathode potential, the higher the generated CH₄, revealing cathode participated in hydrogenotrophic methanogenesis. Taxonomic and functional structure of core microbiome significantly shifted within groups of - 0.36 V and - 0.56 V, with dechlorinators (Desulfitobacterium, Dehalobacter), fermenters (norank_f_Propionibacteriaceae, Dysgonomonas) and methanogen (Methanosarcina) highly enriched, and the more positive interactions between functional genera were found. The lowest number of nodes and links and the highest positive correlations were observed among constructed sub-networks classified by function, revealing simplified and strengthened cooperation of functional genera driven by group of - 0.36 V. Cathode potential plays one important driver controlling core microbiome assembly, and the low potentials drove the assembly of major dechlorinating, methanogenic and electro-active genera to be more deterministic, while, the major fermenting genera were mostly governed by stochastic processes.

Characteristics of groundwater microbial communities' structure under the impact of elevated nitrate concentrations in north China plain

In groundwater environments, the interaction between microbial communities and the hydrogeochemical parameters have been investigated extensively in the past years. However, little is known whether the maximum contamination level (MCL) is a threshold value that dictates the microbial composition. In this study, we analyzed 10 groundwater samples for their nitrate, nitrite, COD and sulfate concentrations, and characterized their microbial compositions using 16 S rRNA based high-throughput sequencing methods. All the 10 samples had oxygen demands higher than the corresponding MCL of China (10 mg L^-1); moreover, 4 out of 10 samples also had nitrate concentrations higher than the corresponding MCL, which indicated that the groundwater quality was negatively impacted by anthropogenic activities. Comparing the microbial composition of groundwater that had higher-than-MCL nitrate concentrations to those that had lower-than-MCL nitrate concentrations, no significant differences were detected in communities' richness and diversity. However, the non-metric multi-dimensional analysis suggested that the 4 groundwater samples whose nitrate concentration exceed MCL are distinctly different from those of the rest 6 samples, indicating that MCL does have a significant impact on microbial structures. Pearson's correlation analysis suggested that none of the four analyzed hydrochemical parameters had significant impact on microbial communities' richness and diversity; however, at the genus level, the correlation results suggested that JG30-KM-CM45, Sphingomonas and Rhodococcus are closely correlated with nitrate concentration. The findings of this study deepened our understanding with respect to the relationships between the environmental quality indices and the microbial compositions of groundwater.

Enhanced sludge dewaterability by ferrate/ferric chloride: The key role of Fe(IV) on the changes of EPS properties

The complex characteristics of extracellular polymeric substances (EPS) seriously affect the improvement of sludge dewaterability. Ferrate (Fe(VI))/ferric chloride (Fe(III)) was applied through its strong oxidability to effectively enhance sludge dewaterablity by changing the properties of EPS in this study. Results confirmed that water content (WC), specific resistance to filtration (SRF) and capillary suction time (CST) fell from 82.8 %, 9.3 × 10¹⁰ s²/g and 35.1 s to 76.1 %, 2.6 × 10¹⁰ s²/g and 16.2 s, respectively, when adding 12 mg Fe(VI)/g VSS and 12 mg Fe(III)/g VSS with the dosing interval of 5 min. Investigations of the mechanism strongly suggested that Fe(VI) was successfully catalyzed by Fe(III), promoting the generation of methyl phenyl sulfone (PMSO₂) and facilitating the electron transfer, with Fe(IV) having the major role in the oxidation process. Furthermore, sludge water-holding capacity and hydrophilicity waned after oxidation due to the destruction of EPS structure, which promoted the decrement of bound water to enhance the discharge of sludge water, so as to improve the efficiency of dewatering.

Rapid biodegradation of atrazine by a novel Paenarthrobacter ureafaciens ZY and its effects on soil native microbial community dynamic

An atrazine-utilizing bacterium, designated as ZY, was isolated from agricultural soil and identified as Paenarthrobacter ureafaciens. The P. ureafaciens ZY demonstrated a significant degradation capacity of atrazine, with the degradation efficiency of 12.5 mg L^-1 h^-1 in liquid media (at pH 7, 30°C, and the atrazine level of 100 mg L^-1). The P. ureafaciens ZY contained three atrazine-degrading genes (i.e., trzN, atzB, and atzC) could metabolize atrazine to form cyanuric acid, which showed lower biotoxicity than the parent atrazine as predicted by Ecological Structure Activity Relationships model. A laboratory-scale pot experiment was performed to examine the degradation of atrazine by P. ureafaciens ZY inoculation and investigate its effects on the native microbial communities. The results exhibited that the P. ureafaciens ZY was conductive to the degradation of atrazine, increased the total soil phospholipid fatty acids at the atrazine level of 50, 70, and 100 mg kg^-1. By using high-throughput sequencing analysis, Frateuria, Dyella, Burkholderia-Caballeronia-Paraburkholderia were considered as the most important indigenous atrazine-degrading microorganisms due to their relative abundances were positively correlated with the atrazine degradation rate. In addition, P. ureafaciens ZY also increased the abundance of atrazine-degrading genus Streptomyces and Bacillus, indicating that there may be a synergic relationship between them in the process of atrazine degradation. Our work provides a new insight between inoculums and native microorganisms on the degradation of atrazine.

Antibiotics degradation by advanced oxidation process (AOPs): Recent advances in ecotoxicity and antibiotic-resistance genes induction of degradation products

Antibiotic contamination could cause serious risks of ecotoxicity and resistance gene induction. Advanced oxidation processes (AOPs) such as Fenton, photocatalysis, activated persulfate, electrochemistry and other AOPs technologies have been proven effective in the degradation of high-risk, refractory organic pollutants such as antibiotics. However, due to the limited mineralization ability, a large number of degradation intermediates will be produced in the oxidation process. The residual or undiscovered ecological risks of degradation products are potential safety hazards and problems necessitating comprehensive studies. In-depth investigations especially on the full assessments of ecotoxicity and resistance genes induction capability of antibiotic degradation products are important issues in reducing the environmental problems of antibiotics. Therefore, this review presents an overview of the current knowledge on the efficiency of different AOPs systems in reducing antibiotics toxicity and antibiotic resistance.

Effect of hydrothermal pretreatment and compound microbial agents on compost maturity and gaseous emissions during aerobic composting of kitchen waste

Though aerobic composting is commonly used in kitchen waste (KW) disposal, the high-oil and high-salt characteristics of KW could affect composting efficiency and lead to the land using risk of produced fertilizer. The impact of hydrothermal pretreatment (HTP) and addition of compound microbial agent (CMA) on compost maturity, greenhouse gas (GHGs) emissions and bacterial community during the kitchen waste composting were evaluated in the present work. Results indicated that N2O, CH4 and CO2 emissions from treatment by HTP and CMA addition were reduced by 82.72%, 13.77% and 20.78 %, respectively, comparing with the control (without HTP and without CMA addition). The seed germination index (GI) value of the HTP and CMA addition treatment was 1.03 and had the highest maturity in all treatments. Furthermore, the bacterial community analysis indicated that CMA inoculation could increase the relative abundance of genus Bacillus at the thermophilic stage of composting to accelerate organic biodegradation. This work provided important insight into mitigating GHGs emissions and improving compost quality in kitchen waste composting.

Oxidation and coagulation/adsorption dual effects of ferrate (VI) pretreatment on organics removal and membrane fouling alleviation in UF process during secondary effluent treatment

Ultrafiltration (UF) has been widely used in water and advanced sewage treatment. Unfortunately, membrane fouling is still the main obstacle to further improvement in the system. Fe (III) salt, a type of traditional coagulant, is often applied to mitigate UF membrane fouling. However, low molecule organic weight cannot be effectively removed, thus the water quality after single coagulation treatment does not effectively meet the standard of subsequent water reuse during secondary effluent treatment. Recently, it has been found that potassium ferrate (Fe (VI)) has multiple functions of oxidation, sterilization and coagulation, with other studies proving its good performance in organics removal and membrane fouling mitigation. However, the respective contributions of oxidation and coagulation/adsorption have not yet been fully understood. The oxidation and coagulation/adsorption effects of Fe (VI) during membrane fouling mitigation were investigated here. The oxidation effect of Fe (VI) was the main reason for organics with the MW of 8-20 kDa removal, and its coagulation/adsorption mainly accounted for the smaller amounts of molecular organics removed. The oxidation of Fe (VI) was the main method for overcoming membrane fouling in the initial filtration; it largely alleviated the standard blockage. The formation of a cake layer transformed the main membrane fouling alleviation mechanism from oxidation to coagulation/adsorption and further removed smaller amounts of molecule organics with the increase of filtration cycles and Fe (VI) dosages. The main fouling mechanism altered from standard blocking and cake filtration to only cake filtration after Fe (VI) treatment. Overall, the mechanism of the oxidation and coagulation/adsorption of Fe (VI) were differentiated, and would provide a reference for future Fe (VI) pretreatment in UF membrane fouling control during water and wastewater treatments.

Microplastics contamination in groundwater of a drinking-water source area, northern China

Although the contamination of microplastics (MPs) in groundwater has been anticipated, their occurrence, distribution, and composition require further understanding. In this study, the occurrence and distributions of MPs were investigated in shallow groundwater from an important water source district in Tianjin city of northern China. The abundance, the physical morphology, the chemical composition, and the potential correlations of the determined MPs with human activities were thoroughly characterized. MPs were determined from all ten sampling sites with the abundance ranged between 17.0 ± 2.16 to 44.0 ± 1.63 n/L, revealing the ubiquitous existed MPs contamination. Based on the physical categorization, fiber (44.74%) was the most abundant shape, while blue (31.02%) and transparent (26.09%) were the most prevalent colors. The dominant size of MPs was smaller than 200 μm which accounted for 73.10%. A total of seven types of MPs were determined with polyethylene, polyethylene terephthalate, and polystyrene as the main types, of which, polypropylene showed strong positive correlations with polystyrene, indicating the possible similar sources of them. Besides, the determined MPs in groundwater were greater in areas with the high population density and strong population activity, indicating their high correlation with human activity. The study highlighted the presence of MPs in groundwater of drinking water source in northern China and provided useful information for evaluating the potential ecological effects on water quality safety and human health brought by MPs.

Introduction of oxygen vacancy to manganese ferrite by Co substitution for enhanced peracetic acid activation and 1O2 dominated tetracycline hydrochloride degradation under microwave irradiation

High microwave-response cobalt-substituted manganese ferrite (CMFO-0.5) was successfully synthesized as a heterogeneous catalyst for efficient peracetic acid (PAA) activation and tetracycline hydrochloride (TCH) degradation with singlet oxygen (¹O₂) as the dominated reactive oxidized species (ROS). The removal efficiency of TCH could reach 98.16% within 6 min under microwave irradiation when the CMFO-0.5 was added at 20 mg/L. It's found that the Co substitution could produce the oxygen vacancies (OVs), improve the microwave (MW) absorbing performance and enhance the internal electron transfer efficiency of materials. The phenomenon why ¹O₂ as the dominated ROS rather than hydroxyl radical (•OH) and organic radicals (R-O•) would be explained by the following aspects: the oxygen adsorbed on the OVs can accept the electron transformed from PAA to form superoxide radical (•O₂^-), which will disproportionate to form ¹O₂; the energy generated by the non-thermal effect of MW can dissociate PAA to generate peroxy-group for ¹O₂ generation. Furthermore, the possible TCH degradation pathways were proposed based on DFT theory calculations and product identification, and the toxicity predictions of the degradation products were also performed by the Ecological Structure-Activity Relationship Model (ECOSAR) software. Additionally, the decrease of acute toxicity of treated TCH, excellent stability and strong resistance towards water matrix fully demonstrate the superiority of the proposed system for practical application in wastewater treatment.

Improved performance of an opposite-flow low-pressure ultrafiltration membrane system in the treatment of groundwater containing Fe2+, Mn2+, and NH4. Chemosphere 2022;302:134846. [PMID: 35526683 DOI: 10.1016/j.chemosphere.2022.134846]

In remote areas, low-pressure ultrafiltration membrane (LPM) systems can be applied in decentralized water supplies for the treatment of groundwater containing Fe²⁺, Mn²⁺, and NH₄⁺. However, improving the performance of the LPM systems, such as the stable flux and removal capacity, presents a challenge. In this study, a novel opposite-flow low-pressure ultrafiltration membrane (O-LPM) system was applied, and its performance was evaluated. Experimental results showed that after 46 days of operation, the steady flux of the O-LPM systems were 1.87-fold and 1.74-fold higher than that of the conventional D-LPM systems under Mn²⁺ concentration of 0.3 mg L^-1 and 1.5 mg L^-1, respectively. With a mixed pollutant system containing Fe²⁺ (0.5 mg L^-1), Mn²⁺ (0.3 mg L^-1), and NH₄⁺ (1.0 mg L^-1), the O-LPM-ripening period for Mn²⁺ removal was shortened from 16 days to 8 days, and the NH₄⁺ removal efficiency was increased from 61.46% to 80.97%. The bio-cake layer in the O-LPM systems was thinner and had a higher uniformity than in the D-LPM systems, resulting in a larger stable flux range. The relative abundance of functional bacteria (MnOB, IOB, and NOB) was generally higher in O-LPM systems than in the D-LPM systems. Overall, these results are of high relevance for groundwater treatment in remote areas, providing guidance for the widespread application of the O-LPM system in decentralized water supplies.

Novel insights into the interaction reactive components and synergistic fouling mechanisms of ultrafiltration by natural organic matter fractions and kaolin

The mechanisms governing interactions among various natural organic matter (NOM) fractions and the subsequently impact on ultrafiltration process have not been systematically studied. In this work, bovine serum albumin (BSA), humic acid (HA), sodium alginate (SA) were applied as model NOM to explore the influence of the interactions among NOM on ultrafiltration process. Results indicated that tryptophan-like fluorescence fraction was the dominant reaction fraction of HA to react with SA and BSA. Different interactions among model NOM not only changed the interception order of fluorescence fractions by ultrafiltration from fulvic acid-like, humic-like and tryptophan-like in BSA/HA mixture to tryptophan-like, humic-like and fulvic acid-like in BSA/HA/SA/kaolin mixture, but also remarkably influence the membrane fouling behavior. In BSA/HA mixture, new-generated aggregates with molecular weight (MW) of 10 kDa could not pass though ultrafiltration membrane and mainly contributed to chemical reversible fouling. In BSA/HA/SA mixture, SA simultaneously reacted with BSA and HA to generate aggregates with larger MW which could be washed down by physical cleaning. In BSA/HA/SA/kaolin mixture, the aggregates with MW of 10 kDa and chemical reversible fouling were disappeared due to the adsorption role of kaolin. These findings could further improve our understanding regarding membrane fouling mechanisms of raw water with different components.

Reduced Graphene Oxide Triggers Peracetic Acid Activation for Robust Removal of Micropollutants: The Role of Electron Transfer

Peracetic acid (PAA) serves as a potent and low-toxic oxidant for contaminant removal. Radical-mediated catalytic PAA oxidation processes are typically non-selective, rendering weakened oxidation efficacy under complex water matrices. Herein, we explored the usage of reduced graphene oxide (rGO) for PAA activation via a non-radical pathway. Outperforming the most catalytic PAA oxidation systems, the rGO-PAA system exhibits near-complete removal of typical micropollutants (MPs) within a short time (<2 min). Non-radical direct electron transfer (DET) from MPs to PAA plays a decisive role in the MP degradation, where accelerated DET is achieved by a higher potential of the rGO-PAA reactive surface complexes. Benefitting from DET, the rGO-PAA system shows robust removal of multiple MPs under complex water matrices and with low toxicity. Notably, in the DET regime, the electrostatic attraction of rGO to both PAA and target MP is a critical prerequisite for achieving efficient oxidation, depending on the conditions of solution pH and MP pK_a. A heatmap model building on such an electrostatic interaction is further established as guidance for regulating the performance of the DET-mediated PAA oxidation systems. Overall, our work unveils the imperative role of DET for rGO-activated PAA oxidation, expanding the knowledge of PAA-based water treatment strategies.

Peracetic acid integrated catalytic ceramic membrane filtration for enhanced membrane fouling control: Performance evaluation and mechanism analysis

Endowing ceramic membrane (CM) catalytic reactivity can enhance membrane fouling control in the aid of in situ oxidation process. Peracetic acid (PAA) oxidant holds great prospect to integrate with CM for membrane fouling control, owing to the prominent advantages of high oxidation efficacy and easy activation. Herein, this study, for the first time, presented a PAA/CM catalytic filtration system achieving highly-efficient protein fouling alleviation. A FeOCl functionalized CM (FeOCl-CM) was synthesized, possessing high hydrophilicity, low surface roughness, and highly-efficient activation towards PAA oxidation. Using bovine serum albumin (BSA) as the model protein foulant, the PAA/FeOCl-CM catalytic filtration notably alleviated fouling occurring in both membrane pores and surface, and halved the flux reduction degree as compared with the conventional CM filtration. The PAA/FeOCl-CM catalytic oxidation allows quick and complete disintegration of BSA particles, via the breakage of the amide I and II bands and the ring opening of the aromatic amino acids (e.g., Tryptophan, Tyrosine). In-depth investigation revealed that the in situ generated ^•OH and ¹O₂ were the key reactive species towards BSA degradation during catalytic filtration, while the organic radical oxidation and the direct electron transfer pathway from BSA to PAA via FeOCl-CM played minor roles. Overall, our findings highlight a new PAA/CM catalytic filtration strategy for achieving highly-efficient membrane fouling control and provide an understanding of the integrated PAA catalytic oxidation - membrane filtration behaviors.

Improved decolorization and mineralization of azo dye in an integrated system of anaerobic bioelectrochemical modules and aerobic moving bed biofilm reactor

In this study, a stacked integrated system with anaerobic bioelectrochemical system (BES) and aerobic moving bed biofilm reactor (MBBR) was developed to improve the decolorization and mineralization of azo dye. This stacked BES-MBBR exhibited better performance with acid orange (AO7) decolorization of 96.4 ± 0.6% and chemical oxygen demand (COD) removal of 87.7 ± 4.4%. Contribution of each module in the BES and MBBR stages indicated that BES modules enhanced the pretreatment process in AO7 decolorization, and MBBR played an important role in further removal of COD. The mechanism analysis indicated that the azo bond was cleaved with reductive decolorization at biocathode in the anaerobic BES stages, and then the intermediate products can be further oxidized with COD removal in the aerobic MBBR stage. This work demonstrated that the integrated system with stacked anaerobic BES and aerobic MBBR could provide a promising way for the pretreatment and post-treatment of refractory wastewater.

Advanced oxidation process based on hydroxyl and sulfate radicals to degrade refractory organic pollutants in landfill leachate

As a special type of wastewater produced in the landfill, leachate is mainly composed of organic pollutants, inorganic salts, ammonia nitrogen and heavy metals, and featured by high pollutants concentration, complex composition and large fluctuations in water quality and volume. Biological, chemical and physical methods have been proposed to treat landfill leachate, but much attention has been paid to the advanced oxidation processes (AOPs), due to their high adaptability and organic degradation efficiency. This paper summarizes the recent findings on the AOPs based on hydroxyl radical (OH) (e.g., ozonation and catalyzed ozone oxidations, Fenton and Fenton-like oxidations) and sulfate radical (SO₄^-) (e.g., activated and catalyzed persulfate oxidations), especially the production routes of free radicals and mechanisms of action. When dealing with some special landfill leachates, it is difficult for a single advanced oxidation technology to achieve the expected results, but the synergistic combination with biological or physical methods can produce satisfactory outcomes. Therefore, this paper has summarized the application of these combined treatment technologies on landfill leachate.

Influence of nitrate concentration on trichloroethylene reductive dechlorination in weak electric stimulation system

The co-existence of volatile chlorinated hydrocarbons (VCHs) and nitrate pollution in groundwater is prominent, but how nitrate exposure affects weak-electrical stimulated bio-dechlorination activity of VCH is largely unknown. Here, by establishing weak-electrical stimulated trichloroethylene (TCE) dechlorination systems, the influence on TCE dechlorination by exposure to the different concentrations (25-100 mg L^-1) of nitrate was investigated. The existence of nitrate in general decreased TCE dechlorination efficiency to varying degrees, and the higher nitrate concentration, the stronger the inhibitory effects, verified by the gradually decreased transcription levels of tceA. Although the TCE dechlorination kinetic rate constant decreased by 36% the most, under all nitrate concentration ranges, TCE could be completely removed within 32 h and no difference in generated metabolites was found, revealing the well-maintained dechlorination activity. This was due to the quickly enriched bio-denitrification activity, which removed nitrate completely within 9 h, and thus relieved the inhibition on TCE dechlorination. The obvious bacterial community structure succession was also observed, from dominating with dechlorination genera (e.g., Acetobacterium, Eubacterium) to dominating with both dechlorination and denitrification genera (e.g., Acidovorax and Brachymonas). The study proposed the great potential for the in situ simultaneous denitrification and dehalogenation in groundwater contaminated with both nitrate and VCHs.

Mechanisms Underlying Mu Opioid Receptor Effects on Parallel Fiber-Purkinje Cell Synaptic Transmission in Mouse Cerebellar Cortex

μ-opioid receptors (MOR) are widely expressed in the brain, varying in density in different areas. Activation of MORs underlies analgesia, euphoria, but may lead to tolerance, dependence, and ultimately opioid addiction. The Purkinje cell (PC) is the only efferent neuron in the cerebellar cortex and receives glutamatergic synaptic inputs from the parallel fibers formed by the axons of granule cells. Studies have shown that MORs are expressed during the development of cerebellar cells. However, the distribution of MOR and their effects on PF-PC synaptic transmission remain unclear. To examine these questions, we used whole-cell patch clamp recordings and pharmacological methods to determine the effects and mechanisms of MOR activation on synaptic transmission at PF-PC synapses. The MOR-selective agonist DAMGO significantly reduced the amplitude and area under the curve (AUC) of PF-PC evoked (e) EPSCs, and increased the paired-pulse ratio (PPR).DAMGO-induced inhibitory effects on PF-PC eEPSCs and PPR were abolished by MOR specific blocker CTOP. Further, DAMGO significantly reduced the frequency of PF-PC mEPSCs, but had no obvious effect on their amplitude, suggesting a presynaptic site of action. The DAMGO-induced reduction in the frequency of PF-PC mEPSCs also was blocked by CTOP. A protein kinase A (PKA) inhibitor PKI added in the pipette solution did not affect the inhibitory effects on PF-PC mEPSCs induced by DAMGO. Both the PKA inhibitor K5720 and MEK inhibitor U0126 in artificial cerebrospinal fluid (ACSF) prevented the inhibitory effects of DAMGO on PF-PC mEPSCs. These findings reveal that MORs are expressed in presynaptic PF axon terminals, where DAMGO can activate presynaptic MORs to inhibit PF-PC synaptic transmission by regulating the release of glutamate. G-protein-dependent cAMP-PKA signaling pathway may be involved in this process.

Active Microstructure Transformation and Enhanced Stability of Iron Foam Derived from Industrial Water Oxidation

Tracking microstructure transformation under industrial conditions is significant and urgent for the development of oxygen evolution reaction (OER) catalysts. Herein, employing iron foam (IF) as an object, we closely monitor related morphologies and composition evolution under 300 mA cm^-2 at 40 °C (IF-40-t)/80 °C (IF-80-t) in 6 M KOH and find that the OER activity first increases and then decreases with the continuous generation of FeOOH. Moreover, the reasons for different tendencies of Tafel slope, double-layer capacitance, and impedance for IF-40-t/IF-80-t have been investigated thoroughly. In detail, the OER activity of IF-40-t is governed by electron and mass transport, while for IF-80-t, the dominating factor is electron transfer. Further, to improve the stability, guided by the above results, two versatile methods that do not sacrifice electron and mass transport have been proposed: surface coating and dynamic interface construction. The synchronous improvements of stability and activity are deeply revealed, which may provide inspiration for catalyst design for industrial applications.

Regrowth potential of chlorine-resistant bacteria in drinking water under chloramination

The regrowth of chlorine-resistant bacteria in drinking water can deteriorate water quality. The study evaluated the relationship between organic carbon and the regrowth potential of chlorine-resistant bacteria remaining in chloraminated water samples. The results showed that the community structure of bacteria changed with the increase of chloramine dosage. The order in which organic carbon utilized by bacteria was affected by the composition of bacterial community. The biodegradable dissolved organic carbon (BDOC), assimilable organic carbon (AOC), bacterial regrowth potential (BRP) and total cell concentration (TCC) in cultivated water sample after disinfection with 1.8 mg/L chloramine increased form 0.22 mg/L, 33.68 µg/L, 2.70 × 10⁵ cells/mL and 3.48 × 10⁴ cells/mL before cultivation to 1.20 mg/L, 193.90 µg/L, 4.74 × 10⁵ cells/mL and 1.46 × 10⁵ cells/mL, respectively. The increase of TCC did not result in the decrease of BDOC, AOC and BRP in the cultivated water samples. The results showed that other biodegradable organic carbon in chloraminated water samples assimilated by residual chlorine-resistant bacteria besides AOC, BDOC, and organic carbon assimilated by indigenous bacteria. AOC, BDOC, and BRP indicators used to characterize the biostability of drinking water were not enough to accurately assess the regrowth potential of chlorine-resistant bacteria remaining in drinking water. It is suggested to supplement the index of TCC in cultivated water samples, which might be able to more accurately evaluate the regrowth potential of chlorine-resistant bacteria remaining in drinking water.

Improvement of sludge dewaterability by energy uncoupling combined with chemical re-flocculation: Reconstruction of floc, distribution of extracellular polymeric substances, and structure change of proteins

This study innovatively combines energy uncoupling and chemical re-flocculation helped to accelerate residual sludge dewatering. Ferric chloride (FeCl₃) and 3, 3', 4', 5-tetrachlor-osalicylanilide (TCS) were employed as the flocculant and uncoupler, respectively. The results showed that the specific resistance to filtration (SRF) and the water content of sludge filtered cake fell dramatically from 11 × 10¹² m/kg and 80.2% to 1.1 × 10¹² m/kg and 77.1% respectively, when the addition of TCS ranged from 0 to 0.12 g/g VSS with flocculation conditioning. The distribution of sludge extracellular polymeric substance (EPS) was altered radically after adding TCS, leading to the collapse and fragmentation of EPS, causing the reduction and formation of fragmentized sludge flocs. Meanwhile, the stretching and deformation vibrations of CO and NH bonds suggested the strong attack between TCS and EPS proteins, while variations of the main secondary structures of protein (i.e. α-helix, β-sheet and random coil) indicated the loose structure of proteins and enhanced hydrophobicity. Consequently, the cracked and loose structure of residual sludge resulted in the release of bound water. After TCS addition combined with chemical re-flocculation, the channels of sludge water discharge were widened, guaranteeing the discharge of sludge water. Therefore, the sludge dewaterability was elevated under the energy uncoupling combined with chemical re-flocculation. As well, the application of TCS would not destroy sludge cells, in which bioenergy (sludge carbon source) could be retained and effectively utilized in the subsequent disposal process. The findings reported here not only widen our perception of the energy uncoupling technology, but also encourage researchers to explore both effective and economic methods on the basis of energy uncoupling, aiming to achieve high-efficiency of reduction and dewatering in the future.

Effect of hydrothermal pretreatment on the degrease performance and liquid substances transformation of kitchen waste

Hydrothermal treatment (HT) is a pragmatic approach for pretreatment of kitchen waste (KW). This work investigated the effect of hydrothermal pretreatment (HTP) on the deoiling, desalting and liquid substances transformation of KW. The orthogonal test method was used to study the effects of three factors at five levels, including solid to liquid ratio (A_1-5), heating time (B_1-5) and hydrothermal temperature (C_1-5). The results indicated that the floatable oil content was improved significantly after HTP. The highest floatable oil content was 84.54 mL/kg at the hydrothermal condition of 1/1.5, 20 min and 100 °C, which was 2.42 times higher than the control. The maximum desalination ratio (92.66%) was at A₅B₁C₅ (1/2.5, 5 min, 100 °C), which was 4.48 times higher than control group (No.0) (20.67%). The VFAs concentration was the highest (11441.05 mg/kg) at 1/2.5, 5 min and 100 °C, which increased by 711.03% compared to the No.0 (1410.78 mg/kg). In addition, the maximum TOC value was obtained at 53530.84 mg/kg. After HTP, the acetic acid and butyric acid concentrations of the liquid phase increased, while the ethanol concentration decreased. The contents of T,NH₄⁺-N and organic nitrogen in the liquid phase of the HTP system increased, while NO₃^--N remained at a low level (4.96-20.48 mg/kg). The range and variance analysis showed that the temperature had the greatest effect on the deoiling and the liquid substances transformation of KW among these three factors, followed by solid to liquid ratio and heating time. Based on the orthogonal experiment, the optimal parameters for KW deoiling were A₃ (1/1.5), B₄ (25 min) and C₅ (100 °C). This work provided a reference for the KW deoiling and hence improve the efficient utilization of KW.

[Identification of a novel KIF21A gene mutation in a Chinese family with congenital fibrosis of the extraocular muscles]

The proband presented with bilateral congenital non-progressive ptosis and limitation of eye rotation since childhood. The diagnosis was congenital fibrosis of the extraocular muscles. A new KIF21 pathogenic mutation locus was found. It was a KIF21A-ex20 c.2821C>T (p.Arg941Trp) heterozygous missense mutation, which caused the disease in this family.

Rapid start of high-concentration denitrification and desulfurization reactors by heterotrophic denitrification sulphur-oxidising bacteria

High sulphide concentrations can be toxic to denitrifying and desulphurising microorganisms. In this study, bioaugmentation was used to solve this problem. Pseudomonas sp. gs1 can tolerate 400 mg/L sulphide and converts most of the sulphide into elemental sulphur after 4 h. A solid inoculum of Pseudomonas sp. h1 was prepared. Two reactors, that is, one with and one without inoculum, were simultaneously run for 60 days. Bioreactor II to which bacterial inoculum was added reached a good treatment performance on day 3. The elemental sulphur concentration of the effluent was 342.6 mg/L. It was maintained at 245.3-333.8 mg/L during the subsequent operation. In contrast, reactor I without inoculants achieved the same performance on day 50. High-throughput sequencing shows that Pseudomonas and Azoarcus are the dominant genera. The abundance of the genus Pseudomonas and related denitrifying sulphur-oxidising bacteria in reactor I increases with the operation time. This phenomenon was confirmed by testing the sqr and gltA genes. The quantitative fluorescence PCR test also proves that the addition of bacteria leads to a rapid increase in the sulphur oxidation and carbon metabolism of the activated sludge in the reactor.

Influence on denitrifying community performance by the long-term exposure to sulfamethoxazole and chlortetracycline in the continuous-flow EGSB reactors

The response of the denitrification community to long-term antibiotic exposure requires further investigation. Here, the significantly altered denitrifying community structure and function were observed by continuous exposure to 1 mg/L sulfamethoxazole (SMZ) or chlortetracycline (CTC) for 180 d in the expanded granular sludge bed reactors. Thaurea, positively correlated with SMZ and NO₃^- removal efficiency (NrE), was highly enriched in the SMZ-added reactor, while, Comamons and Acinetobacter were largely inhibited. The acute inhibited and then gradual-recovered NrE (87.17-90.38 %) was observed with highly expressed narG, indicating the adaptability of Thaurea to SMZ. However, the abundance of Thaurea and Comamonas greatly decreased, while Melioribacter and Acinetobacter were largely enriched in the CTC-added reactor. CTC created more serious and continuous inhibition of NO₃^- reduction (NrE of 64.53-66.95 %), with lowly expressed narG. Improved NO₂^- reduction capacity was observed in both reactors (70.16-95.42 %) with highly expressed nirS and nosZ, revealing the adaptability of NO₂^- reduction populations to antibiotics.

Effects of the metabolic uncoupler TCS on residual sludge treatment: Analyses of the microbial community and sludge dewaterability potential

Residual sludge is a by-product with a large volume and complex composition from wastewater treatment plants. It is significant to reduce sludge volume to decrease the negative effects of sludge on environmental pollution and needless land use. We investigated the effects of uncoupler 3, 3', 4', 5-tetrachlorosalicylanilide (TCS) on the properties of sludge. After adding 0.12 g TCS/g VSS with 24 h mixing, the sludge concentration and total ATP content decreased by 51.1% and 60.8%, respectively. At the same time, the microbial community also changed significantly, leading to the decrease of richness and diversity. Additionally, the secretion of extracellular polymeric substances (EPS) reduced approximately 43% under the addition of 0.12 g/g VSS compared with the control. The decrement of EPS may be explained by the decreased relative abundance of functional bacteria (i.e. Chloroflexi reduced about 60% and Nitrospirota reduced about 31%). Notably, the addition of TCS before coagulation conditioning (FeCl₃) promoted the adhesion of sludge flocs according to the theory of Extended Derjaguin Landau Verwey Overbee (XDLVO), leading to the increased hydrophobicity of the residual sludge. Therefore, energy uncoupling has the potential of improving sludge dewaterability.

Template-free synthesis of Mn2+ doped hierarchical CuS yolk-shell microspheres for photocatalytic reduction of Cr(VI)

Yolk-shell structures have been widely used in catalysis and energy storage in recent years because they improve the efficiency of charge utilization by enhancing light scattering and creating more active...

Advances in pretreatment of lignocellulosic biomass for bioenergy production: Challenges and perspectives

As a clean and renewable energy, bioenergy is one of the most promising alternatives to fossil fuels. Lignocellulose possesses great potential for bioenergy production, but the recalcitrant and heterogeneous structure limits its application. Pretreatment technology offers an effective solution to fractionate the main components of the lignocellulose and uncover the available cellulose. The obtained feedstock can be applied to bioconversion into energy, e.g., bioethanol, biogas, biohydrogen, etc. Here, the current state of lignocellulose pretreatment technologies was comprehensively reviewed, the advances in bioenergy production from pretreated lignocellulose was described, with particular attention to key challenges involved. Several new strategies for overcoming pretreatment barriers to realize highly efficient lignocellulose bioconversion were highlighted. The insights given in this review will facilitate further development on lignocellulosic bioenergy production, towards addressing the global energy crisis and climate change related to the use of fossil fuels.

Presence of powdered activated carbon/zeolite layer on the performances of gravity-driven membrane (GDM) system for drinking water treatment: Ammonia removal and flux stabilization

Gravity-driven membrane (GDM) filtration is a promising alternative for decentralized water supply, while its widespread application was hindered by the poor removals of organics and ammonia during long-term operation. In this study, powered activated carbon (PAC) and granular zeolite were selected as typical adsorbents to investigate the impacts of pre-deposited adsorbent layers on contaminant removal and membrane fouling. Results showed that the pre-deposited PAC layers exhibited higher removal of organics than the control, while the zeolites deposited layers exhibited low removal of organics. The presence of PAC only enhanced the NH₄⁺ removal at subsequent stable stage, while zeolites were effective in deal with sudden high NH₄⁺ concentration due to ion exchange. The presence of mixed adsorbents layers had similar organic removal with PAC and NH₄⁺ removal with zeolite. The pre-deposited PAC layers could effectively alleviate membrane fouling in short-term UF tests, while the stable fluxes (5.88-6.54 L/(m²·h)) in long-term GDM operation were slightly lower than the control (6.63 L/(m²·h)). The zeolites deposited layer aggravated membrane fouling in both short-term ultrafiltration and long-term GDM (5.03-3.84 L/(m²·h)), but a higher stable flux (6.10 L/(m²·h)) was observed for GDM using the mixed adsorbents. The pre-deposited adsorbent layers resulted in increased concentrations of biomass, tri-phosphate (ATP) and extracellular polymeric substances (EPS), forming cake layers with a denser structure than the control. Finally, the fouling mechanism for GDM using different adsorbent layers was proposed based on fouling analysis and characteristics of biological fouling layer. The results and conclusion in this study could provide helpful information for the application of GDM with pre-deposited adsorbent layer in treating raw water with organics and/or sudden high ammonia concentration to produce potable water.