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Four different synthetic routes (co-precipitation, oxidation–precipitation, citric acid sol–gel and reversed microemulsion) are adopted to prepare barium modified Pd/CeO2–ZrO2 catalysts and their catalytic activity towards CO, HC and NOx conversions is studied. The surface and bulk properties of these catalysts are characterized via XRD, N2 adsorption, XPS, UV-Raman, H2-TPR, and in situ DRIFTS. The catalyst prepared via the co-precipitation method exhibits the optimum three-way catalytic behavior, which is mainly due to its superior redox ability, whereas the oxidation–precipitation synthesis renders the catalyst with the best homogeneity and thermal resistance. However, for the catalyst prepared via the sol–gel route, its worst NOx reduction capacity is verified by the scarce appearance of negatively charged Pd0–N=Oδ− species, which is related to the faster dissociation of NO based on in situ DRIFTS, and the abundance of surface CO–Pd+ species reveals its unsatisfactory deep oxidizability of the HC reactant. [ABSTRACT FROM AUTHOR]

Two novel clusters [CoII14(μ6-O2−)(sbha)12(sba)2 (DMF)7(DMA)]·(DMF)8 (1) and [NiII14(μ6-O2−)(sbha)12(sba)2(DMF)8] (2) (sH2bha = 4-bromo-benzohydroximic acid; sHba = 4-bromobenzene carboxylic acid; DMF = N,N-dimethylformamide; DMA = dimethylamine) have been synthesized. The novel body-centred μ6-O2− bridged Co14 and Ni14 clusters are packed in distorted face-centered cubic (FCC) patterns with different symmetries. Magnetic studies confirmed the antiferromagnetic exchange interactions between magnetic centers. [ABSTRACT FROM AUTHOR]

Highlights: [•] PdO x species are mainly dispersed on Al2O3-rich grains surface in fresh catalysts. [•] PdO x species migrate to (Ce,Zr) x O2-rich grains surface after aging treatment due to Pd-(Ce,Zr) x O2 interaction. [•] Interaction between PdO x species and (Ce,Zr) x O2 promotes the thermal stability. [•] Co-precipitation preparation method improves catalysts thermal stability. [Copyright &y& Elsevier]

The coordination polymer [Cd(HL)(BPDA)] n · nH2O ( 1) based on 3-(5-(pyridin-4-yl)-1 H-1,2,4-triazol-3-yl)pyridine (HL) and 1,1′-biphenyl-4,4′-dicarboxylic acid (H2BPDA) was hydrothermally synthesized and characterized by single-crystal X-ray diffraction, XRPD, IR spectroscopy, and elemental analysis. The asymmetric unit of compound 1 consists of one crystallographically independent CdII ion, one HL ligand, 'two half' BPDA2- ligand, and one lattice water molecule. There are two crystallographically different BDPA2- moieties, but each of them is placed in a symmetry element. The BPDA2- ligands and CdII ions connected to2D sheet, and the 2D sheets are connected to a 3D MOF by the HL ligands. Each dimeric CdII unit links six nearest neighbors through the BPDA2- and HL ligands, and the dimeric CdII units are centrosymmetric. Two parallel HL ligands connect two dimeric CdII units, generating long Cd2-HL-Cd2-HL rings, also centrosymmetric. So we can define the dimeric CdII unit as a 6-connected node. Thus, the 3D structure can be described as a threefold parallel interpenetrated bsn beta-Sn topology. In addition, the optical properties of compound 1 and the free ligand H L were investigated. [ABSTRACT FROM AUTHOR]

Highlights: [•] PdO x species maintain oxidized state and good thermal stability on Pd–Ce interface. [•] PdO x species migrate from Al2O3-rich grains to ceria-based oxide surface after aging treatment. [•] Pd/Ce0.67Zr0.33O2–Al2O3 catalyst shows good thermal stability. [•] Surface reaction of CO, HC and NO x on the catalysts has been studied in detail by in-situ drifts. [Copyright &y& Elsevier]

[Display omitted] • A sensitive and reliable SPE-LC-MS/MS method was developed for estrogen determination. • The limits of detection (LODs) for six estrogenic compounds were between 2.5 and 19.2 ng/L. • The effects of matrix background on determination were evaluated and interpreted. • Both matrix suppression and enhancement were observed in environmental samples. • There was a positive correlation between LODs and TOC in various water matrices. An analytical method has been developed and validated for the determination of six estrogens and estrogen mimics, namely estriol (E3), bisphenol A (BPA), 17β-estradiol (E2), estrone (E1), ethynyl estradiol (EE2) and dienestrol (DIE), with frequent occurrence in the natural environment. Solid phase extraction coupled with liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS) using electrospray ionization (ESI) in a negative mode was applied to concentration, identification, and quantification of estrogens and estrogen mimics. The SPE conditions were optimized as the selection of C18 as cartridges and MeOH as an eluent, and the control of solution pH at 9.0. The method was validated by satisfactory recoveries (80–130%) and intra-day and inter-day precision (<18.4%, as relative standard deviation), and excellent linearity for calibration curves (R2 > 0.996). The limits of detection (LODs) for six target estrogenic compounds ranged between 2.5 and 19.2 ng/L. The effects of matrix background on the determination were evaluated in terms of LODs, LOQs, analyte recovery, and slopes of calibration curves in five different water matrices. Matrix effects by tap water were negligible. However, both matrix suppression and enhancement (i.e., E3, E1, DIE) were observed in surface water and wastewater. The positive correlation between LODs and TOC in various water matrices indicated the negative effect of organic pollutants on the method sensitivity. The sum of target estrogenic compounds in environmental samples were within 17–9462 ng/L. [ABSTRACT FROM AUTHOR]

High amounts of antibiotics, used in animal farms for the prevention of diseases, are released back into the natural environment with a possible risk of chronic toxicity to other organisms and the development of antibiotic-resistant genes. The antibiotics, including sulfonamides and β-lactams, detected in swine wastewater were between 99.2 and 339.3 μg/L. The typical on-site swine wastewater treatment process turned out to be inadequate, reflected by the high conventional contaminant and antibiotic residuals even under a long hydraulic residence time (HRT, around 2–3 months). The lab-scale combined anaerobic and aerobic biological process showed that anaerobic digestion was mainly responsible for chemical oxygen demand (COD) reduction and aerobic biodegradation contributed significantly to antibiotic removal, with overall removal efficiencies of 95% for COD and 92% for antibiotics under a short HRT of 3.3 days. The removal of selected antibiotics could be a combined result of biodegradation, the balance between adsorption and desorption, and the transformation between antibiotic metabolites and their parent antibiotics. The current work provides valuable insights into the appropriate selection and optimisation of biological processes for the treatment of typical wastewater with high COD and trace antibiotics. Unlabelled Image • The total antibiotic concentrations in swine wastewater were 99.2–339.3 μg/L. • The combined anaerobic and aerobic treatment removed 95% COD and 92% antibiotics. • The fate of antibiotics should be a combined result of biodegradation, adsorption and transformation. • Higher HRT for aerobic process resulted in better antibiotic degradation performance. [ABSTRACT FROM AUTHOR]

A novel vortex-assisted dispersive liquid–liquid microextraction method based on deep eutectic solvent (VA–DLLME–DES) completed in syringe has been established to extract 12 quinolones from honey. This method is an improvement of traditional DLLME. In this work, the green DES prepared with heptanoic acid and thymol was used for extractant rather than traditional organic extraction solvent. Without centrifugation, the phases were separated in the way of removing aqueous phase by pushing the syringe and extractant phase was collected for ultra performance liquid chromatography-mass spectrometry (UPLC–MS) analysis. The stability of DES and some experimental parameters (type, molar ratios and volume of extraction solvent, type and volume of dispersant, vortex time and effect of pH and NaCl) were evaluated. In the range of 2–100 ng/mL, the proposed method showed good linearities (r2 ranged from 0.996 to 0.999). The extraction recoveries were obtained in the range of 75.01%–117.05% and relative standard deviations were less than 13.83% for inter- (n = 6) and intra-day (n = 3) precisions. The limits of detection and quantification were 3 ng g−1 and 10 ng g−1, respectively. The developed method with the advantages of simple operation, short extraction time and less consumption organic solvent provides a technical idea for green, simple and time-saving sample preparation methods. [ABSTRACT FROM AUTHOR]

Interfacial photothermal evaporation offers a promising and cost-effective method of obtaining freshwater. Traditional photothermal evaporators, when exposed to sunlight, typically have a heating region on their surface with temperature higher than room temperature. This can lead to thermal radiation loss and reduce evaporation efficiency. Therefore, this study presents an innovative design and fabrication of a fabric-based conical roll (FCR) evaporator, which enables low-temperature evaporation without a distinct heating region and facilitates the reversal of the thermal radiation path. In particular, the FCR-7.5-45 evaporator demonstrated remarkable performance even under 2.0 sun illumination, showcasing its advanced light-harvesting capability and excellent thermal management ability attributable to the conical spiral groove structure. The unique cold evaporation surface of the 3D evaporators, combined with this design, resulted in a high evaporation efficiency of 151.53 % and a rapid evaporation rate of 3.47 kg·m−2·h−1 under 1.0 sun illumination. Furthermore, the freshwater produced by the FCR evaporator met the drinking water standards set by international regulatory bodies. This indicates that the photothermal evaporator developed in this project holds great potential for widespread application in desalination and sewage treatment. [Display omitted] • A fabric-based conical roll (FCR) evaporator with 3D conical spiral groove structure design was successfully prepared. • The prepared 3D evaporator possessed advanced light-harvesting and thermal management design. • The evaporation rate and evaporation efficiency of FCR-7.5-45 were up to 3.47 kg·m−2·h−1 and 150.98 % respectively (1.0 sun). [ABSTRACT FROM AUTHOR]

Metal nanoparticles (MNPs) have garnered significant attention due to their exceptional performance in heterogeneous reactions. Meanwhile, extensive applications have been found for metal-organic frameworks (MOFs), known for their ordered structure and high surface area. In this study, MNPs particles were amalgamated with MOFs to create a core-shell structure and were introduced amino groups into this configuration through post-synthetic modification (PSM), resulting in the successful synthesis of six distinct nanomaterials. Comprehensive characterization techniques, including infrared spectroscopy (IR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), confirmed the synthesis and modification of the MNPs/MOFs materials. These synthesized materials were employed as catalysts for the condensation reaction of jasminaldehyde. It is noteworthy that these catalysts exhibited outstanding performance, showcasing advantages over traditional heterogeneous catalysts. This superior performance is attributed in part to the advanced core-shell structure of these materials and the effective introduction of amino functional groups through the PSM technique. [ABSTRACT FROM AUTHOR]

This work investigates the enhancement on lubrication performances of water lubricants by multilayer graphene via molecular dynamics simulation. It is found that the multilayer graphene shows interlaminar sliding in the commensurate or incommensurate pattern and thus contributes to an ultra-low friction. Such ultra-low friction can be degraded by agglomerations of graphene, since these agglomerations complicate spatial behaviors of graphene and limit water diffusions, thus affecting the lubrication performances. Moreover, the synergistic performances of water and multilayer graphene become much more evident than the case with monolayer graphene. In detail, the multilayer graphene can promote water lubricants show multilayer distribution and enhance their local diffusions, and water molecules can induce the overlapping of graphene sheets thus to cause their interlaminar sliding. [ABSTRACT FROM AUTHOR]

[Display omitted] • Impacts of NH 2 OH and N 2 H 4 on the SDAD process were studied. • NH 2 OH and N 2 H 4 showed different potential for NO 2 − and N 2 O accumulation. • NIR/N 2 OR were sensitive to NH 2 OH inhibition, while N 2 H 4 primarily suppressed N 2 OR. Hydroxylamine (NH 2 OH) and hydrazine (N 2 H 4) are crucial intermediates in biological nitrogen removal processes, but their potential effects on the nitrogen-related metabolic pathway during the sulfur-driven autotrophic denitrification (SDAD) process remain unclear and were thus explored in this work. The results of dedicated batch tests indicated that the accumulation ratio of NO 2 − was positively correlated with the NH 2 OH concentration, reaching 86.2 ± 2.6% at the NH 2 OH concentration of 2.0 mg-N/L, while it was barely affected by the N 2 H 4 concentration. Furthermore, the joint inhibition of NH 2 OH and free nitrous acid led to the substantial accumulation of N 2 O (up to 32.9 ± 1.3%) during the NO 2 − reduction phase. In contrast, N 2 H 4 exhibited great potential for facilitating N 2 O accumulation in both the NO 3 − reduction and NO 2 − reduction phases with an accumulation ratio of 13.0 ± 0.3% and 27.5 ± 1.5%, respectively, at the N 2 H 4 concentration of 2.0 mg-N/L. Total enzyme activity analyses revealed that the presence of NH 2 OH inhibited the activity expression of all denitrifying enzymes, with the downstream enzymes (such as NO 2 − reductase and N 2 O reductase) being more susceptible to NH 2 OH. The addition of N 2 H 4 did not cause a significant decrease in the activity of NO 3 − reductase and NO 2 − reductase, but notably curbed the activity of N 2 O reductase. Based on the responses of the SDAD-related nitrogen metabolic pathway to NH 2 OH/N 2 H 4 , this work provided effective technical means for i) the promotion of NO 2 − accumulation which might enable the coupling of SDAD with Anammox and ii) the efficient recovery of N 2 O via the SDAD process. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cations can regulate the aggregation of polysaccharide chains to affect fouling. • The gel layer homogeneity and permeability are mainly related to the TEP type. • Amorphous-TEP form a compact fouling layer with high filtration resistance. • Particulate-TEP form a porous gel layer, pre-filtrate foulants and alleviate fouling. • The resistance of fouling layer to cleaning is also subject to the Ca2+/Mg2+ ratio. Divalent cations and organics are two main types of foulants in feed water to the membrane processes and cations often bind to organic foulants which significantly affects fouling. Extensive efforts have been devoted to exploring the influence of single cation on organic fouling while there are diverse cations in the feed. Thus, it is essential to understand the coupling influence of different divalent cations on fouling development. In this study, sodium alginate was chosen as a model foulant to investigate the effect of different Ca2+/Mg2+ ratios on its fouling behavior. Filtration performances, the quantity and morphology of transparent exopolymer particles (TEP) derived from alginate were analyzed along with the morphology and structure of corresponding fouling layers. TEP measurements reveal that the Ca2+/Mg2+ ratio is crucial in the characteristics of TEP, which further determines the structure of the fouling layer. At a low Ca2+/Mg2+ ratio, the TEP are amorphous-TEP (a-TEP) with small and unconsolidated structure which forms a fouling layer under pressure with high hydraulic resistance. In contrast, interactions between polysaccharides at high Ca2+/Mg2+ ratio are much stronger and result in large and tight particulate-TEP (p-TEP). Such p-TEP lead to a fouling layer with high porosity and low hydraulic resistance. The role of Mg2+ in polysaccharide fouling is more important than expected because it promotes the formation of a-TEP, which show a high fouling potential at high levels because more dense gel layer forms. This study suggests that the morphology and structure of TEP play crucial roles in polysaccharide fouling propensities. A-TEP at high levels needs more attention to ensure the successful operation of membrane systems in future work. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ideal influent substrates conditions for n-DAMO/anammox-based granular bioreactor. • Smaller granules rich in n-DAMO archaea/AnAOB accelerated bioreactor start-up. • Low diffusivity of solutes promoted bioreactor start-up and CH 4 utilization. In this work, a bioprocess model was applied to first determine the impacts of influent substrates conditions on the granular bioreactor performing nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) and anammox integrated processes and then investigate the roles of granular sludge properties in regulating the bioreactor performance and start-up process. The ideal influent substrates conditions were identified at NO 2 −-N/NH 4 +-N of 1:1 and dissolved CH 4 concentration of 85 g COD m−3, which achieved 98.6% total nitrogen removal and 87.7% dissolved CH 4 utilization. Under such ideal influent conditions, the initial properties of granular sludge didn't significantly affect the granular bioreactor performance. However, inoculation of granular sludge with a relatively small granular sludge size and a high abundance of n-DAMO archaea or/and anammox bacteria could effectively shorten the bioreactor start-up. Meanwhile, reducing the diffusivity of solutes within granular sludge was also beneficial for expediting the start-up process and promoting dissolved CH 4 utilization. [ABSTRACT FROM AUTHOR]

The core-shell structure of magnetic Metal-Organic Frameworks (MMOFs) was composed of magnetic nanoparticles (MNPs) based on γ-Fe2O3@SiO2-NH2-COOH, metal salts and ligands. The imatinib (IMA-3) and methotrexate (MTX) were loaded into the MMOFs via one-pot reaction, and the release performance of MMOFs was explored. Amino groups were introduced into the MMOFs by Post-Synthetic Modification (PSM) of diethylenetriamine (2,3-NH2) and 4-aminopyridine (4Py). Dye adsorption testing was used as a characterization method to verify the degree of Post-Synthetic Modification of samples. Three types of MMOFs with good degrees of modification were selected through methyl orange adsorption, followed by the folic acid modification. The successful modification of folic acid (FA) of the MMOFs was verified by methylene blue adsorption. By a variety of representational means, the synthesis and PSM were confirmed by infrared spectroscopy (IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Comparing the release performance in vitro of MMOFs loaded with imatinib (IMA-3) and methotrexate (MTX), it showed that the release performance of MMOFs loaded with MTX was better. The release performance of MTX before and after the modification of MMOFs was compared, which indicated that the drug delivery performance of MMOFs might not be significantly affected after PSM. [ABSTRACT FROM AUTHOR]

The presence of polyethylene terephthalate (PET) microplastics (MPs) in waters has posed considerable threats to the environment and humans. In this work, a heterogeneous electro-Fenton-activated persulfate oxidation system with the FeS 2 -modified carbon felt as the cathode (abbreviated as EF-SR) was proposed for the efficient degradation of PET MPs. The results showed that i) the EF-SR system removed 91.3 ± 0.9 % of 100 mg/L PET after 12 h at the expense of trace loss (< 0.07 %) of [Fe] and that ii) dissolved organics and nanoplastics were first formed and accumulated and then quickly consumed in the EF-SR system. In addition to the destruction of the surface morphology, considerable changes in the surface structure of PET were noted after EF-SR treatment. On top of the emergence of the O-H bond, the ratio of C-O/C=O to C-C increased from 0.25 to 0.35, proving the rupture of the backbone of PET and the formation of oxygen-containing groups on the PET surface. With the verified involvement and contributions of SO 4 •- and •OH, three possible paths were proposed to describe the degradation of PET towards complete mineralization through chain cleavage and oxidation in the EF-SR system. [Display omitted] • EF-SR achieved 91.3 ± 0.9 % removal of 100 mg/L PET after 12 h at trace loss of FeS 2. • Dissolved organics and nanoplastics were formed/accumulated and quickly consumed. • Considerable changes in surface morphology and structure of PET MPs were noted. • 3 possible paths were proposed to describe PET degradation/mineralization in EF-SR. [ABSTRACT FROM AUTHOR]

• Satellite high-precision estimation for plant diversity is extremely needed. • Simple linear regression models were the worst. • Partial linear regression model was moderate. • Random forest model performed best. • NDVI and its standard deviation are the best predictors for plant alpha diversity. At present, the accuracy of remote sensing estimation models of plant alpha diversity is generally low, and high-precision estimation models in deciduous broadleaved forest (DBF), deciduous coniferous forest (DCF) and evergreen coniferous forest (ECF) are still lacking. The main purpose of this study is to construct high-precision remote sensing models for plant alpha diversity in multiple ecosystems at global scale. Normalized Difference Vegetation Index (NDVI) were derived from Sentinel-2 data. NDVI and NDVI based spectral diversity/heterogeneity indices were selected as predictive variables, and alpha diversity indices were selected as response variables. Simple linear regression (SLR), partial linear regression (PLSR), and random forest (RF) models were used to evaluate the predictive ability of the predictive variables against the response variables under six ecosystems (evergreen broadleaved forest (EBF), DBF, ECF, DCF, shrub, and grassland), and to compare the estimated robustness of various spectral diversity indices. In terms of prediction accuracy, the SLR models were the worst, and the PLSR model were average. RF performed best, outperforming most current models. Especially in DBF, ECF, shrub and grassland, the determination coefficient R2 of RF models can be as high as 0.9. In terms of the prediction of α-diversity, the prediction effect of species richness was better than that of Shannon index, Simpson index and Pielou index. The higher the vegetation complexity, the more accurate the assessment of vegetation α-diversity tends to be, especially in DBF, shrub and grassland. According to the importance of predictive variables and model stability evaluation results, NDVI, standard deviation of NDVI (SD), and NDVI derived Shannon's diversity index (Sha), Cumulative Residual Entropy (CRE), Pielou's evenness index (Pie), Hill's numbers (Hill), Berger-Parker's diversity index (Ber), Parametric Rao's index of quadratic entropy (paRao) are all powerful indicators for predicting plant alpha diversity. Among them, the prediction performance of NDVI and SD is better. This study is not only an exploration of the practicability of R package "rasterdiv", but also an attempt to construct high-precision remote sensing estimation models of plant alpha diversity at global scale. [ABSTRACT FROM AUTHOR]

[Display omitted] • The membrane fouling was effectively alleviated at low voltage of 0.1 V/cm. • Electric field decreased the EPS content and extended the service time. • Electric field reduced the irreversible fouling and enhanced effluent quality. • Increased Patescibacteria and decreased Bacteroidetes mitigated membrane fouling. The electrical assisted MBR (EMBR) has been employed to improve the water quality and solve the fouling problem. However, advanced material-based electrodes or high operation voltage bring difficulties for the practical application of EMBR. Herein, a weak electric field generated by titanium electrodes was employed to establish an EMBR and the fouling mechanism was investigated in detail. The results showed that introduction of a weak electric field at voltage of 0.1 V/cm and current density of 7 μA/cm2 efficiently decreased the extracellular polymeric substances (EPS) content by over 40 % as such extended the service time of MBR by more than 20 %. Specifically, the weak electric field reduced the relative abundance of Bacteroidetes , known for secreting proteinaceous EPS, by 38.61 %, and increased relative abundance of Patescibacteria with EPS decomposition by 6.73 times, thus effectively reducing the EPS concentration. Further KEGG pathway analysis revealed that electric field accelerated enzymatic reactions and promoted microbial metabolism of carbohydrate and amino acid. Furthermore, this weak field reduced the sludge deposition on membrane by increase of the electrostatic repulsion and the irreversible fouling was mediated. According to the composition of the fouling layer, a corresponding cleaning scheme was applied. This EMBR consistently produced high-quality effluent in all cycles, with 99.31 % COD, 98.73 % NH 4 +-N, 85.87 % TP and 92.66 % TN removals. In conclusion, the weak electric field endow EMBR exceptional anti-fouling ability and superior effluent quality under lower energy consumption. [ABSTRACT FROM AUTHOR]

• A model comprising C/N/S-related bioprocesses was developed and evaluated. • Impact of H 2 S on MBfR/granular bioreactor performing anammox/n-DAMO was assessed. • H 2 S content in inflow gas (v/v: 0∼5%) did not significantly affect MBfR. • Influent H 2 S of granular bioreactor lowered TN removal or increased energy demand. The coupling between anammox and nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) has been considered a sustainable technology for nitrogen removal from sidestream wastewater and can be implemented in both membrane biofilm reactor (MBfR) and granular bioreactor. However, the potential influence of the accompanying hydrogen sulfide (H 2 S) in the anaerobic digestion (AD)-related methane-containing mixture on anammox/n-DAMO remains unknown. To fill this gap, this work first constructed a model incorporating the C/N/S-related bioprocesses and evaluated/calibrated/validated the model using experimental data. The model was then used to explore the impact of H 2 S on the MBfR and granular bioreactor designed to perform anammox/n-DAMO at practical levels (i.e., 0∼5% (v/v) and 0∼40 g/S m3, respectively). The simulation results indicated that H 2 S in inflow gas did not significantly affect the total nitrogen (TN) removal of the MBfR under all operational conditions studied in this work, thus lifting the concern about applying AD-produced biogas to power up anammox/n-DAMO in the MBfR. However, the presence of H 2 S in the influent would either compromise the treatment performance of the granular bioreactor at a relatively high influent NH 4 +-N/NO 2 −-N ratio (e.g., >1.0) or lead to increased energy demand associated with TN removal at a relatively low influent NH 4 +-N/NO 2 −-N ratio (e.g., <0.7). Such a negative effect of the influent H 2 S could not be attenuated by regulating the hydraulic residence time and should therefore be avoided when applying the granular bioreactor to perform anammox/n-DAMO in practice. [Display omitted] [ABSTRACT FROM AUTHOR]

UiO66 is a new MOFs material that attracts the most attention. Its unique characteristics lead to its good thermal stability. In this paper, as for the Knoevenagel reaction, UiO66 and other UiO series MOFs were synthesized and modified. UiO66 particles were prepared by one-pot method. 2-aminopyridine, 3-aminopyridine and 4-aminopyridine were used to prepare UiO66-2Py, UiO66-3Py and UiO66-4Py particles. UiO66-2Py, UiO66-3Py and UiO66-4Py particles were modified by activated arginine, lysine and glycine to synthesize UiO66-2Py-Arg, UiO66-3Py-Lys and UiO66-4Py-Gly. Finally, the obtained samples were used for the Knoevenagel catalytic condensation reactions of benzaldehyde and ethyl cyanoacetate. In this process, the prepared samples and their intermediates were characterized by infrared spectroscopy (IR) and X-Ray diffraction (XRD), which showed that the modification of UiO66 was successful. UiO66-3Py-Lys and UiO66-4Py-Gly showed high catalytic activity in the supernatant determined by fluorescence spectrophotometer, and UiO66-4Py-Gly showed the best catalytic effects at the volume of 0.4 mL benzaldehyde. [ABSTRACT FROM AUTHOR]

[Display omitted] • Applied electric field lengthened the run time of the MBR system by 23.4 %. • Introduction of an electric field significantly improved the effluent quality of MBR. • Intermittent power mode was much better than continuous mode. • EMBR is an effective and chemical-free technique in fouling control. The hydrophobic polyvinylidene fluoride (PVDF) membrane is one of the most widely used membrane material in the treatment of domestic sewage, while it still endures the fouling problem. Many studies have focused on the fouling control, among which the electrochemical membrane bioreactor (EMBR) is promising because of its chemical-free nature, but the specific influence of applied electric field on the mitigation of membrane fouling and the treatment effect are unclear and need further exploration. In this work, the influence and interaction of operation parameters (operation voltage, electrode spacing, power-on mode, and hydraulic retention time) on fouling development and pollutants removals in a PVDF based EMBR were carefully explored for the optimal operating conditions. Results showed that the run time of EMBR system under optimal conditions was 23.4 % longer than that of the MBR system without a weak electric field, indicating that the membrane fouling problem was well alleviated. In addition, the effluent quality of EMBR was also improved than that treated by the MBR system. The removal rates of chemical oxygen demand, ammonia nitrogen, total phosphorus, and total nitrogen were increased by 2.25 %, 2.64 %, 9.02 %, and 12.1 %, respectively, revealing the improvement of this EMBR system in sewage treatment. This work shows that introduction of a weak electric field in MBR system not only effectively controls membrane fouling, but also increases the effluent quality, and thus endows EMBR as a candidate for sustainable and green technique in sewage treatment. [ABSTRACT FROM AUTHOR]

• Enrichment of comammox Nitrospira in a mainstream SBR in the step-feeding mode. • Candidatus Nitrospira nitrosa was the dominant (∼95 %) comammox species enriched. • Identification of K NH4 -N and K O2 for enriched comammox bacteria-dominant sludge. • Floccular sludge enriched with comammox Nitrospira possessed low N 2 O and NO yields. The discovery of complete ammonium oxidation (comammox) has subverted the traditional perception of two-step nitrification, which plays a key role in achieving biological nitrogen removal from wastewater. Floccular sludge-based treatment technologies are being applied at the majority of wastewater treatment plants in service where detection of various abundances and activities of comammox bacteria have been reported. However, limited efforts have been made to enrich and subsequently characterize comammox bacteria in floccular sludge. To this end, a lab-scale sequencing batch reactor (SBR) in the step-feeding mode was applied in this work to enrich comammox bacteria through controlling appropriate operational conditions (dissolved oxygen of 0.5 ± 0.1 g-O 2 /m3, influent ammonium of 40 g-N/m3 and uncontrolled longer sludge retention time). After 215-d operation, comammox bacteria gradually gained competitive advantages over counterparts in the SBR with a stable nitrification efficiency of 92.2 ± 2.2 %: the relative abundance of Nitrospira reached 42.9 ± 1.3 %, which was 13 times higher than that of Nitrosomonas , and the amoA gene level of comammox bacteria increased to 7.7 ± 2.1 × 106 copies/g-biomass, nearly 50 times higher than that of conventional ammonium-oxidizing bacteria. The enrichment of comammox bacteria, especially Clade A Candidatus Nitrospira nitrosa , in the floccular sludge led to (i) apparent affinity constants for ammonium and oxygen of 3.296 ± 0.989 g-N/m3 and 0.110 ± 0.004 g-O 2 /m3, respectively, and (ii) significantly low N 2 O and NO production, with emission factors being 0.136 ± 0.026 % and 0.023 ± 0.013 %, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanofiltration (NF) membranes are increasingly recognized for their proficiency in monovalent/divalent ion separation, making them highly suitable for application such as water softening and resource recovery. This study introduces an innovative in-situ hydrolysis method to enhance the ion selectivity of thin-film composite nanofiltration (TFC-PA NF) membranes. In this method, the reactive monomer in the oil phase was pre-hydrolyzed by contacting with water, producing a partially hydrolyzed monomer that remained soluble in the oil phase. This in-situ hydrolysis process introduced more carboxylic groups to the membrane. That could lead to a proper enlargement of the pore size, subsequently facilitating the separation of Cl−/SO 4 2−. Additionally, the hydrolysis altered the polarity of the acyl chloride molecule, prompting its accumulation at the oil/water interface and accelerating the polymerization reaction rate. This resulted in a thin and exceptionally smooth PA layer. The resulting membrane exhibited a remarkable Cl−/SO 4 2−separation factor of ∼316 under moderate feed concentration and ∼478 under high feed concentration, while maintaining decent water permeance (14.4 L m−2 h−1 bar−1). Moreover, its maintained surface carboxylic group density, combined with ultra-low surface roughness, offered drastically enhanced fouling resistance. Our study illuminates the pathway for a straightforward and scalable method to fabricate highly selective membranes with superior fouling resistance. [Display omitted] • A novel in-situ hydrolysis process was used to prepare ultraselective NF membrane. • The hydrolyzed monomer tended to accumulate at interface and modulate IP process. • The NF membrane possessed a remarkably high separation factor of Cl−/SO 4 2−. • The NF membrane had an ultrasmooth surface with an improved antifouling performance. [ABSTRACT FROM AUTHOR]

Under global climate change, we can adjust landscape patterns to mitigate the effects of climate factors on crop yield. Field and landscape-scale research suggests that increased land cover diversity and non-crop habitats can improve crop yield, but little is known on the effects of patch area and shape of one type of land use (i.e., class-level) and spatial patterns (aggregation, fragmentation, and heterogeneity) of surrounding multiple land-use classes (i.e. landscape-level) on crop yield. We evaluated the relationship between 375 landscape metrics at both class- and landscape-levels, 120 climate variables, and the crop yields of maize, rice, and wheat in China from years 2000–2015 at national and sub-climatic zone scales. Our results suggest that both class- and landscape-level patterns were the main drivers, contributing averagely 12% of the variations in crop yields. Specifically at national scale, crop yield in cropland with forest cover (>27%) was increased by 169% than where without forest cover. Shape complexity in forest and cropland patches, aggregation degree, and spatial complexity of land cover types were more closely associated with crop yield (accounting for 2–73% of the variations in crop yield at sub-climatic zones) than landscape diversity (<2%), mainly owing to their mediating effects on the relationship between climate factors and crop yield. Not all non-crop habitats are beneficial to crop yield, and forest patches with a suitable area and shape complexity perform best. Our findings suggest that the regulation of both class- and landscape-level patterns may be an alternative way to improve crop yield, rather than only enhancing land-cover diversity or increasing the area of non-crop habitats. • Both class- and landscape-level landscape patterns influence crop yield. • The crop yield in the landscape with forest cover (>27%) was increased by 169%. • Land shape complexity (6%) and area (7%) contributed more to the variation of crop yield than landscape diversity (∼2%). • Most suitable class- and landscape-level patterns to improve crop yield were suggested. [ABSTRACT FROM AUTHOR]

Manganese oxide activated peroxymonosulfate (PMS) has gradually become one of the research focuses in the field of advanced oxidation. In this work, β-cyclodextrin (β-CD) modified amorphous manganese oxide (CD-AM) catalyst was obtained from a mild reaction condition (80 °C oil bath), high temperature crystallization is avoided in the synthesis process, which reduces the difficulty of catalyst preparation process and energy consumption. β-CD is involved in the formation of manganese oxides. Amorphous manganese oxides have larger specific surface area and better PMS activation effect than crystalline manganese oxides, which is different from previous studies. The enrichment of cyclodextrin on BPA can improve the removal activity of amorphous manganese oxide/PMS system on BPA. The introduction of β-CD increased the bisphenol A (BPA) degradation efficiency from 33.1% to 99.4%, and brought the kinetic constant to its 14.9 times. The 94% BPA degradation efficiency was obtained under neutral conditions that is more favorable for the actual process. During the degradation process, 1O 2 and ·OH were the main ROS in CD-AM/PMS system, and O·- 2 not only promoted the conversion of O·- 2 to 1O 2 but also accelerated the cycle of Mn (III)/Mn (IV). In addition, a simpler material recovery process for application was achieved by transforming CD-AM into the "supported membrane" (AMSM), and better performance and lower Mn ion leaching concentration were accessible. With the utilization of AMSM, Mn ion concentration in the filtrate after first filtration was about 1.2 mg/L, which was only 37% of the Mn ion concentration firstly detected in CD-AM. And after four cycles, the BPA degradation efficiency was 96.9%. When AMSM/PMS system was used to treat BPA in river water, the final degradation efficiency reached 94.8%. CD-AM as a catalyst for activating PMS shows great application potential in actual water. [Display omitted] • A catalyst for efficient activation of PMS was synthesized using a simple one-pot method. • The performance of crystalline and amorphous manganese oxides in activating PMS was compared. • The mechanism of BPA degradation process in CD-AM/PMS system was analyzed. • The performance and reusability of supported membranes (AMSM) in actual water body was studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • A SNAD model aimed to recover N 2 O from Fe(II)EDTA-NO was developed and evaluated. • Impacts of key operational conditions on N 2 O recovery were studied. • S/N mass ratio of ∼ 1.0 and high gas/liquid volumetric ratios favoured N 2 O recovery. • N 2 O recovery efficiency of up to 80.2%−84.9% was reached within 3.1 h–3.5 h. Instead of the conventional perception of nitrous oxide (N 2 O) as a potent greenhouse gas whose production should be minimized, this work aimed to assess N 2 O recovery as a potential energy source from nitric oxide (NO) in the form of Fe(II)EDTA-NO through element sulfur (S0) or thiosulfate (S 2 O 3 2−)-driven NO-based autotrophic denitrification (SNAD S0 or SNAD S2O3). A mathematical model was proposed to describe substrate dynamics related to N 2 O production and reduction and was successfully calibrated and validated using batch experimental data from lab-scale SNAD S0 and SNAD S2O3 systems under different substrates conditions. The model was subsequently employed to assess the potential of N 2 O accumulation and recovery by altering the S/N mass ratio and the ratio of gas volume to liquid volume of the system. The simulation results suggested that with a S/N mass ratio of nearly 1.0, high-purity N 2 O could be more rapidly and efficiently recovered from Fe(II)EDTA-NO in the SNAD S0 and SNAD S2O3 systems with a higher ratio of gas volume to liquid volume (i.e., a N 2 O recovery efficiency of up to 80.2%−84.9% reached within 3.1 h−3.5 h under the studied conditions). Comparatively, the SNAD S0 process showed an economic and viable advantage for practical applications to the efficient treatment and resource utilization of NO-containing flue gas. [ABSTRACT FROM AUTHOR]

[Display omitted] • Melamine content affects the size of Ni0 core and the property of N species in carbon shell. • Core-shell electron transfer decides p -CNB hydrogenation activity for Ni@C-N/SiO 2. • N -doped carbon shell protects Ni0 core from thiophene adsorption. • Ni@C-N/SiO 2 has higher TOF than Raney Ni in thiophene-involved hydrogenation. How to break the activity-selectivity dependence in halonitrobenzene hydrogenation remains a challenge. In this work, Ni@C N/SiO 2 were synthesized and examined in the hydrogenation of p -chloronitrobenzene. It showed that the electron transferred from nitrogen doped carbon shell to Ni0 core (core–shell synergistic effect) dominated the intrinsic activities of Ni@C N/SiO 2 with dual-reaction surfaces (H 2 dissociated on Ni0 core, while p -chloronitrobenzene was hydrogenated on carbon shell) in the thiophene-free hydrogenation, leading to their higher turnover frequencies than Raney Ni catalyst. During the thiophene-involved hydrogenation, the adsorption of thiophene on Ni0 changed its electron density and blocked the active sites. These enhanced the selectivity, but significantly reduced the activity for Raney Ni catalyst. Comparatively, the carbon shell protected Ni0 core from thiophene adsorption so that the hydrogen dissociated on Ni0 as usual. However, the adsorption of thiophene on the carbon shell reduced the available sites for p -chloronitrobenzene adsorption. Although Ni@C N/SiO 2 had lower activities in the thiophene-involved reactions than those of thiophene-free reactions, they achieved ∼100 % p-chloroaniline selectivities and 8-fold higher turnover frequencies than Raney Ni, breaking the activity-selectivity dependence. This reveals that the available sites on the carbon shell and the core–shell synergistic effect determine the thiophene-involved hydrogenation activities of Ni@C N/SiO 2 catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mechanisms of EF and fundamentals/necessity of cathode modification. • Current cathode modification methods with reported performances in removing POPs. • Pros/cons and perspectives of cathode modification for EF degradation of POPs. The Electro-Fenton (EF) technology has received significant research attention because of its efficacy in the degradation of persistent organic pollutants (POPs), which mainly relies on the in-situ generation of H 2 O 2 via the 2-electron oxygen reduction reaction and the subsequent formation of •OH. However, the practical application of the EF technology still needs to deal with shortcomings such as the limited performance of the traditional heterogeneous catalyst and the restricted generation of •OH that could be overcome by performing modification on the cathode. This work reviewed the reported cathode modification methods including thermal and (electro)chemical treatment and modification based on materials such as metals, graphene, carbon nanotubes, and polymers. Furthermore, the documented performances of the EF systems with differently modified cathodes in degrading specific POPs were presented. Finally, the advantages and limitations of these cathode modification methods were discussed, and some research perspectives were proposed to improve the practicability and feasibility of the EF technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • Al3+ and Fe3+ change the fouling mechanism via regulating the foulants. • Al3+ controls the formation of TEP from polysaccharide foulants. • The characteristics of TEP determines the permeability of the fouling layer. • An optimal level of coagulant alleviates membrane fouling can be obtained. Membrane fouling caused by organics in feedwater is a bottleneck factor limiting the development of membrane technology, which is often alleviated by addition of coagulants. However, the effect mechanism of coagulant components on organic foulants are lack of in-depth analysis. In this study, sodium alginate is selected as the surrogate of organic foulants to study the influence mechanism of typical coagulants Al3+ and Fe3+ on fouling control, especially the impact on the morphological characteristics of foulants at the micro level and the related fouling mitigation mechanism. The results show that the addition of different concentrations of coagulants will deeply affect the process of polysaccharide aggregation to form transparent exopolymer particles (TEP). Combination of filtration tests and analysis of fouling mechanism reveal that the small and amorphous TEP developed at low concentration of coagulant is intercepted by the membrane and forms a dense fouling layer resulting in the decreasing of membrane flux, while larger granular TEP developed from alginate accumulates on the membrane surface to form a porous fouling layer which in turn acts as a pre-filtering layer mitigating fouling. This study indicates that the addition of coagulants significantly changes the microscopic properties of foulants and thus the fouling problems. With the qualitative and quantitative analysis of TEP formed by foulant, the theoretical basis and data support are provided for the addition of coagulation to construct an effective pre-filtering layer for membrane fouling control. This work therefore, provides an effective way in application of coagulants for more accurate fouling control. [ABSTRACT FROM AUTHOR]

[Display omitted] • Time-dependent forward and reverse Hermia model fitting was used to process the filtration data. • The new fitting method declared the membrane fouling mechanism and fouling layer structure. • The Hermia classic model is more appropriate for processing the filtration data with Ca2+ in cross-flow filtration. • The Hermia mass-transfer model is more suitable for fitting the filtration data with Mg2+ in cross-flow filtration. The Hermia fouling models are often applied in interpreting filtration data to reveal the fouling mechanisms. However, the application of these models is arbitrary and lacks in-depth analysis. In this study, time-dependent Hermia models with forward and reverse processing were employed for the first time to analyze the membrane fouling mechanism and fouling layer structure determined by polysaccharide in dead-end and cross-flow filtration. The applicability of Hermia classic and mass-transfer models was also investigated. Results showed that in cross-flow filtration, the Hermia classic model is more suitable for processing the filtration data with Ca2+ and the Hermia mass-transfer model is more appropriate for fitting the experiment result caused by Mg2+ owning to the differences in affinity of Ca2+ and Mg2+ to polysaccharide. Fitting results further manifested that the differences in concentration could obviously affect structure of polysaccharide fouling layer, and the introduction of Ca2+ and/or Mg2+ changed the spatial conformation and compactness of fouling layer. These results suggested that Hermia fouling models can provide insightful analysis of the fouling layer structure from micro-level to interpret the fouling mechanisms. The influence of cation concentration and type on membrane fouling can be revealed by the processing of Hermia models. In short, time-dependent forward and reverse processing of Hermia classic and mass-transfer models could preliminarily explain the membrane fouling behavior and structure of fouling layer. This work suggests that the Hermia fouling models are more useful than we thought and the time-dependent application of them could provide deep insights into fouling development. [ABSTRACT FROM AUTHOR]

• Insensitive TN removal to longitudinal heterogeneity at non-excessive CH 4 supply. • Longitudinal gradient in liquid phase affected biomass stratification/CH 4 utilization. • Recommended plug flow operation for MBfR with co-current flow of wastewater and CH 4. Integrating anammox with denitrifying anaerobic methane oxidation (DAMO) in the membrane biofilm reactor (MBfR) is a promising technology capable of achieving complete nitrogen removal from wastewater. However, it remains unknown whether reactor configurations featuring longitudinal gradients parallel to the membrane surface would affect the performance of the CH 4 -driven MBfR. To this end, this work aims to study the impacts of longitudinal heterogeneity potentially present in the gas and liquid phases on a representative CH 4 -driven MBfR performing anammox/DAMO by applying the reported modified compartmental modeling approach. Through comparing the modeling results of different reactor configurations, this work not only offered important guidance for better design, operation and monitoring of the CH 4 -driven MBfR, but also revealed important implications for prospective related modeling research. The total nitrogen removal efficiency of the MBfR at non-excessive CH 4 supply (e.g., surface loading of ≤0.064 g-COD m−2 d−1 in this work) was found to be insensitive to both longitudinal gradients in the liquid and gas phases. Comparatively, the longitudinal gradient in the liquid phase led to distinct longitudinal biomass stratification and therefore played an influential role in the effective CH 4 utilization efficiency, which was also related to the extent of reactor compartmentation considered in modeling. When supplied with non-excessive CH 4 , the MBfR is recommended to be designed/operated with both the biofilm reactor and the membrane lumen as plug flow reactors (PFRs) with co-current flow of wastewater and CH 4 , which could mitigate dissolved CH 4 discharge in the effluent. For the reactor configurations with the biofilm reactor designed/operated as a PFR, multi-spot sampling in the longitudinal direction is needed to obtain a correct representation of the microbial composition of the MBfR. Graphical abstract [Display omitted]. [ABSTRACT FROM AUTHOR]

[Display omitted] • Impacts of granule properties on reactors performing partial nitritation/anammox. • Big anammox-enriched granules inoculated for high TN removal & low N 2 O production. • Optimum boundary layer thickness increased with decreasing diffusivity in granules. This work studied the impacts of key granule properties on the granular reactor performing partial nitritation/anammox from the modeling perspective. The results could guide not only future reliable modeling but also practical startup/operation of the reactor. To achieve high total nitrogen (TN) removal whilst avoiding significant N 2 O production, inoculated granules should be big and anammox-enriched. The optimum boundary layer thickness for maximum TN removal increased with the decreasing diffusivity of soluble components in the granule structure. Even though a thick boundary layer could protect anammox bacteria from elevated dissolved oxygen (DO) (e.g., 0.5 g-O 2 /m3) and obtain high TN removal (>90.0%) and low N 2 O production (<1.8%), even complete removal of the boundary layer would fail to provide sufficient substrate for anammox and therefore couldn't increase TN removal to 90.0% and decrease N 2 O production to <2.4% at insufficient DO (e.g., 0.3 g-O 2 /m3 in the presence of lifted influent NH 4 + concentration). [ABSTRACT FROM AUTHOR]

Water-based lubricants with graphene have excellent lubrication behaviors, but the synergistic mechanism involving the activities of both water and graphene isblue still unclear. This work investigates such mechanism by considering the effect of different factors such as the number of water molecules, loading, surface roughness and sliding velocity via molecular dynamics simulation. It is found that the friction reduction by water-based lubricants is due to the enhanced isolation between friction pairs by the graphene presence and the improvement of water replenishment. The synergistic lubrication mechanism works as that the water molecules may protect the structural integrity of graphene by inducing its movement to release lateral stresses and the graphene can enhance the movement of water molecules and promote their rolling like bearings. • Water can protect the structural integrity of graphene by inducing its movement. • Graphene can enhance the diffusions of water molecules and promote their rolling. • Low friction is due to better water replenishments and pairs isolation by graphene. • Water amount highly changes the friction force by affecting the contact interface. • Friction fluctuation with water-based lubricants is insensitive to various loadings. [ABSTRACT FROM AUTHOR]

Even though modeling has been frequently used to understand the autotrophic deammonification-based membrane-aerated biofilm reactor (MABR), the relationships between system-specific biofilm property settings and model predicted N 2 O production have yet to be clarified. To this end, this study investigated the impacts of 4 key biofilm property settings (i.e., biofilm thickness/compactness, boundary layer thickness, diffusivity of soluble components in the biofilm structure, and biofilm discretization) on one-dimensional modeling of the MABR, with the focus on its N 2 O production. The results showed that biofilm thickness/compactness (200–1000 μm), diffusivity of soluble components in the biofilm structure (reduction factor of diffusivity: 0.2–0.9), and biofilm discretization (12–28 grid points) significantly influenced the simulated N 2 O production, while boundary layer thickness (0–300 μm) only played a marginal role. In the studied ranges of biofilm property settings, distinct upper and lower bounds of N 2 O production factor (i.e., the percentage ratio of N 2 O formed to NH 4 + removed, 5.5% versus 2.3%) could be predicted. In addition to the microbial community structure, the N 2 O production pathway contribution differentiation was also subject to changes in biofilm property settings. Therefore, biofilm properties need to be quantified experimentally or set properly to model N 2 O production from the MABR correctly. As a good practice for one-dimensional modeling of N 2 O production from biofilm-based reactors, especially the MABR performing autotrophic deammonification, the essential information about those influential biofilm property settings identified in this study should be disclosed and clearly documented, thus ensuring both the reproducibility of modeling results and the reliable applications of N 2 O models. [Display omitted] • Impacts of 4 key biofilm properties on modeling N 2 O production from MABR. • Distinct upper and lower bounds of modeled N 2 O production factor (5.5% vs 2.3%). • Disclosure of quantified/set biofilm properties as a good modeling practice. [ABSTRACT FROM AUTHOR]