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This study proposes the risk assessment framework of water distribution networks with a focus on the determination of weights of various risk indices. First, the pipe risk list is built, in which pipe failure probability and consequence are considered. By integrating the analytic hierarchy process (AHP) and the entropy weighting method (EWM), the weights of these indices are obtained by the combined weighting method (CWM), by which both human experience and data distribution can be considered comprehensively. Taking a real WDN in an industrial zone in China as an example, the proposed method is demonstrated in detail and the risks of all pipes are determined. The accuracy of the CWM is validated from the perspective of risk levels of pipes with historical failure records. It is found that the AHP or EWM underestimates or overestimates pipe risks, respectively. Compared to them, the CWM provides reasonable results. In addition, the risks of plastic pipes, newly buried pipes less than five years old, and pipes over twenty years old are much higher. [ABSTRACT FROM AUTHOR]

In this study, grape seed oil nanoliposomes (GSO-NLs) were constructed and doped into tapioca starch/konjac gum composite films (TK-GSO-NLs) to evaluate the preservation of chilled mutton. The results showed that the GSO-NLs have a good spherical or rounded state and good stability. The doping of GSO-NLs resulted in a smooth, flat, and dense structure on the surface and cross-section of the TK films. The TK-GSO-NLs showed the best compatibility among the components, with excellent mechanical and barrier properties. FTIR and XRD confirmed the presence of ionic bonds between the components, further improving the copolymer crystal structure. Notably, the packaging material provided ideal antioxidant and bacteriostatic stability as well as delayed GSO release. This packaging could effectively maintain the quality of chilled mutton and prolong the shelf-life to 15 days. The study provides ideas for the design of green and active food packaging and for extending the shelf life of meat. [Display omitted] • Grape seed oil nanoliposomes (GSO-NLs) are uniform spherical with smooth surface and good stability. • Tapioca starch/konjac gum film (TK-GSO-NLs) loaded with GSO-NLs improved mechanical properties and barrier properties. • Ionic bonding interactions between the film components improve the crystal structure of the copolymer. • The TK-GSO-NLs provided ideal antioxidant, bacteriostatic stability and delayed release. • The TK-GSO-NLs could effectively maintain the quality of chilled mutton and prolong the shelf-life. [ABSTRACT FROM AUTHOR]

[Display omitted] • Butyl xanthate was treated by a micro-nano bubble enhanced Fenton process. • The coupled process achieved 100% degradation of butyl xanthate. • Micro–nano bubbles improved the utilization of oxidant. • The coupled process achieved an 80% removal of total organic carbon in wastewater. Xanthates are the main trapping agents used in the processing of metallic sulfide ores and residual xanthates in beneficiation wastewater can potentially contaminate the environment at the mine site. Finding efficient methods to degrade butyl xanthates has received much attention. Micro–nano bubble (MNB) and advanced oxidation technologies (AOPs) have recently become increasingly important as effective treatment methods. In this study, the degradation of butyl xanthate was investigated through a micro–nano bubble-enhanced Fenton process (hydrogen peroxide (H 2 O 2)/ peroxymonosulfate (PMS) /Fe2+). The effects of the process parameters (pH, coexisting ions, oxidant dosage (PMS, H 2 O 2), and Fe2+ dosage) on the degradation of butyl xanthate were investigated. Results showed that the H 2 O 2 /PMS/Fe2+ process resulted in a 100 % degradation rate for butyl xanthate and 66 % total organic carbon (TOC) removal rate. With the enhancement of the degradation process using MNBs, the TOC removal rate increased to 80 %. The hydroxyl and superoxide radicals were identified as the main active substances in the degradation of butyl xanthate through electron spin resonance. Introducing H 2 O 2 into the PMS/Fe2+ process increased the strength of hydroxyl and superoxide radicals in the reaction system. In addition, following the introduction of the MNBs, the amount of dissolved oxygen in the reaction system increased. As a result, the production of active substances in the reaction system increased. The synergistic effect of MNBs and the Fenton process caused an increase in the TOC removal rate. This implies that the multiprocess coupling technology of the MNB-enhanced Fenton process has great potential in the field of wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Compared the butyl xanthate degradation by sulfite, PDS, PMS for the first time. • CoFe 2 O 4 activated sulfite/persulfate efficiently degraded butyl xanthate. • Treating catalysts enhances their adaptability to various catalytic systems. • The active free radicals that play a major role in each system were detected. • The key factor in free radical formation is the cyclic reaction at the Co site. Owing to the technological limitations associated with beneficiation technology, large amounts of flotation reagents remain in mineral processing wastewater, which is extremely detrimental to humans and the environment. In addition, direct reuse of mineral processing wastewater will adversely affect the entire mine water system. Efficient treatment of residual butyl xanthate from tailing wastewater has recently attracted increasing interest. In this study, we compared the degradation efficiencies of cobalt iron oxide (CoFe 2 O 4) nanoparticles assisted by sulfite-activated advanced processes and persulfate (PDS) and peroxymonosulfate (PMS) advanced oxidation processes on butyl xanthate (BX) for the first time and explored possible reaction mechanisms in various systems. We conducted comprehensive experiments on the acid/alkali washed catalysts using oxidizing agents, obtaining catalysts best adapted to three degradation systems. Results of batch experiments indicated that the BX degradation rate for all the three systems exceeded 95 % within 60 min under their respective optimal conditions and that the best total organic carbon content (TOC) removal rate for these systems was 85.79 %. The effects of key factors, such as catalyst dosage, oxidant dosage, solution pH, and coexisting ions, on BX degradation were investigated. Furthermore, the active free radicals that played a major role in each system were detected via electron paramagnetic resonance (EPR). EPR results indicated that SO 3 ·− and ·O 2 − were the main active species of the CoFe 2 O 4 /sodium sulfite system, ·OH and ·O 2 − participated in the degradation of BX in the CoFe 2 O 4 /PDS system, and ·O 2 − was present in the CoFe 2 O 4 /PMS system. Thus, this study promotes the application of CoFe 2 O 4 with magnetism as a catalyst in wastewater treatment and provides new insights into the effective treatment of organic pollutants in tailing wastewater. [ABSTRACT FROM AUTHOR]

In the present study, the structure of potato oxidized hydroxypropyl starch (OHS) was analyzed. Carrageenan (CA) was used as a reinforcing agent for the development of biodegradable food packaging materials. Broccoli leaf polyphenol/soybean protein isolate/hydroxypropyl methylcellulose composite nanoparticles (SPH NPs) were used to reinforce OHS/CA (OC) films, and their physicochemical, structural, antioxidant, antimicrobial, and biodegradable properties were characterized. The OHS had high transparency, low gelatinization temperature (GT), and easy film formation. Intermolecular hydrogen bonds were formed between the SPH NPs and the OC film matrix, but did not change the crystal structure of the matrix. Furthermore, the incorporation of SPH NPs improved the smoothness, densification, and thermal stability of the OC films. Since SPH NPs occupied the pores of the film matrix, the degree of swelling, light, and moisture-blocking properties were improved, causing the films to gradually turn red, yellow and dark. Notably, the tensile strength of the film was significantly increased from 11.06 MPa to 13.61 MPa at a concentration of 3% SPH NPs. The SPH NP 3 -loaded films showed scavenging activity up to 67.62% and 75.45% against DPPH and ABTS free radicals, with good inhibitory activity against S. aureus and E. coli. More importantly, the composite film was almost completely degraded after 45 d of burial in the soil, and it can regulate the soil microbial community. Consequently, OHS composites can be used as a potentially versatile and environmentally friendly film-forming material for food packaging. [Display omitted] • Oxidized hydroxypropyl starch had high transparency and easy film formation. • The composite films exhibited strong robust, water-resistant, UV-blocking, thermal stability. • Electrostatic interaction and hydrogen bonding were formed between nanoparticles and film matrix. • The composite films displayed strong antibacterial, antioxidant and biodegradable properties. • The composite nanoparticle film offers eco-friendly strategy for the preparation of active packaging. [ABSTRACT FROM AUTHOR]

In order to solve the problem of low activity of advanced oxidation processes (AOPs) in degrading high-salt organic wastewater. This study demonstrates a strategy to improve catalyst activity by co-doping with FeCu between the reduced graphene oxide (rGO) and graphitic carbon nitride (g-C 3 N 4) layers. The g-C 3 N 4 -FeCu-rGO (GR-FeCu) reaction system achieved a phenol degradation rate of >96% in high-salinity wastewater, with a pH range of 2–8. After six cycles, the phenol degradation rate reached 100%. Electron spin resonance analysis identified·OH and·O 2 - as the primary active species in phenol degradation. The high activity of the catalyst in high-salt environments is attributed to the synergistic effect of FeCu and rGO-g-C 3 N 4 : The introduction of FeCu suppressed the formation of g-C 3 N 4 , leading to more defect structures and active groups (C O and C-N = C) in the catalyst. These structures provided active sites for H 2 O 2 activation, enhanced H 2 O 2 activation. The doping of Cu in the catalyst not only accelerates the accelerated Fe (III) reduction in the Fenton reaction, but also enhances the activity of N in g-C 3 N 4. The three-dimensional interlayer structure with FeCu co-doping stabilized the metal ions and provided abundant active sites and metal anchoring structures, presenting a new approach to improve catalytic activity. • FeCu catalysts were prepared for the degradation of phenol in high-salt environments. • Control of the structure and activity of catalysts to improve salt resistance. • RG-FeCu showed 100% degradation of phenol after 6 cycles of recycling. • Three-dimensional FeCu catalysts with excellent salt-tolerance properties. • Preparation of FeCu catalysts with a wide range of pH (2-8) applications. [ABSTRACT FROM AUTHOR]

A generalized water retention curve (WRC) model in a wide suction range considering the initial void ratio is presented in this paper. Both capillary and adsorbed water in soil pores are considered. Based on the experimental results that the adsorbed water content w a is not dependent on the initial void ratio, a new degree of saturation equation of adsorbed water is established. Meanwhile, a new degree of saturation equation of capillary water at various initial void ratios is proposed with a void ratio-related expression of the air entry value. Compared to Lu's model, only one parameter b is introduced in the established model, which can be easily calibrated using WRCs under two initial void ratios. The measured WRC results of 5 soils are used to verify the proposed model in comparison with the other 3 widely used WRC models. The soil used in the model validation covers a wide range of soil types from sandy soil to clay soil, including clayey silty sand, sandy clay till, clayey silt, expansive soil and lateritic soil. The proposed model is well verified for its ability to describe soil water retention characteristics in a wide suction range at various initial void ratios. [ABSTRACT FROM AUTHOR]

This study investigated the effect of chitosan coating with grape peel extracts (CH + GPE) on the physiochemical properties, protein and lipid oxidation, microstructure, and bacterial community diversity of beef during freeze–thaw (F–T) cycles. The results indicated that the CH + GPE groups had lower pH values, total aerobic count, total volatile base nitrogen, and thiobarbituric acid reactive substance values and better protection against color, water holding capacity, and sensory quality after five F–T cycles. The CH + GPE coating effectively inhibited beef microstructure destruction during the F–T cycles. High-throughput sequencing analysis revealed that the CH + GPE coating contributed to a decline in the bacterial diversity of beef and inhibited the growth of pathogenic bacteria. Interestingly, the CH + GPE coating affected the correlation between quality parameters and bacteria in beef. Consequently, the CH + GPE coating can be used as a novel packaging for preventing the loss of frozen meat quality due to temperature fluctuations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cheddar cheese could be prepared by using Tenebrio Molitor rennet (TMR). • TMR could degrade proteins to form GABA and Orn during cheese ripening. • GC-IMS was used in this study to identify flavour variations during cheese ripening. • Esters were the most abundant during cheese ripening, which can be a marker of cheese ripening. • Flavor fingerprint in cheese during ripening can be established by GC-IMS and PCA. This study aimed to evaluate the potential application of Tenebrio Molitor rennet (TMR) in Cheddar cheese production, and to use gas chromatography-ion mobility spectrometry (GC-IMS) to monitor flavor compounds and fingerprints of cheese during ripening. The results indicated that Cheddar cheese prepared from TMR (T F) has fat content significantly lower than that of commercial rennet (C F) (p < 0.05). However, the results of the sensory evaluation showed that there were no statistically significant differences between the two kinds of cheese (p > 0.05). Both cheeses were rich in free amino acids and free fatty acids. Compared to the C F cheese, gamma-aminobutyric acid and Ornithine contents of the T F cheese reached 187 and 749 mg/kg, respectively, during 120 days of ripening. Moreover, GC-IMS provided information on the characteristics of 40 flavor substances (monomers and dimers) in the T F cheese during ripening. Only 30 flavor substances were identified in the C F cheese. The fingerprint of the two kinds of cheese during ripening can be established by GC-IMS and principal component analysis based on the identified flavor compounds. Therefore, TMR has potential application in Cheddar cheese production. GC-IMS might be applied for the quick, accurate and comprehensive monitoring of cheese flavor during ripening. [ABSTRACT FROM AUTHOR]

• Tapioca starch and pectin (TSP) showed high compatibility as good film-forming substrates. • Polyphenols from Broccoli leaves have superior antioxidant properties. • Broccoli leaf polyphenols (BLP) were incorporated into TSP films to develop novel active films. • BLP improves the denseness and mechanical properties of TSP + BLP composite films. • These films could extend the quality and shelf life of the mutton during chilled storage. This study aimed at the composition of active packaging film from tapioca starch/pectin (TSP) incorporated with broccoli leaf polyphenols (BLP) was prepared and applied to improve the qualities of the chilled mutton during storage. The results indicated the addition of BLP significantly improved the thickness, density, barrier ability, mechanical properties, water solubility and antioxidant activity of the composite films while inducing decreases in the brightness (p < 0.05), enhancing inter-molecular interactions of TSP + BLP composite films. The WVP, oxygen permeability and elongation at break of the composite film reached the minimum when BLP concentration was 3 % while exhibiting the highest tensile strength and the best performance. This composite film delayed microbial growth and minimized oxidative rancidity during chilled mutton storage, causing the improvement of its quality and extending its shelf life to 12 days. Therefore, TSP + BLP composite films possessed the promise to be applied as bioactive materials in food packaging sectors. [ABSTRACT FROM AUTHOR]

This paper proposes a resilience-based pipe optimal recovery model of water distribution networks (WDNs). First, the time-dependent consumer demands are simulated to reflect the real hydraulic status of WDNs during post-earthquake recovery. Herein, three kinds of consumers are incorporated, including shelter, hospital, and ordinary users. Second, to reflect the asynchronous supply plans of crew and equipment, the phased supply plan of the two types of recovery resources are modeled respectively. Third, the ground motion filed is constructed by the attenuation law, by which the damage conditions of WDN can be descript in detail. By the comprehensive consideration of hydraulic analysis, pipe damage, pipe recovery, and ground motion field, the recovery strategies of critical and general pipes are optimized by heuristic genetic algorithm. This framework is demonstrated taking the Mianzhu WDN as an example. Results show the system satisfaction degree curve has multi-stage characteristics caused by the time-dependent consumer demands and recovery resources supply schedules. The effectiveness of the methodology is validated by comparing different recovery strategies. Meantime, different recovery resource supply schedules are analyzed to reveal the impacts on seismic resilience of WDNs. [ABSTRACT FROM AUTHOR]

Because of the electrically charged property of clay particles, the compacted clay is capable of blocking the passage of solutes in pore fluid and is applied as the buffer material in landfills. However, during the assessment of barrier efficiency in landfills, one of the most important influence factors, i.e., the fixed charge, is neglected. Based on this, an innovative chemo–hydro–mechanical (C–H–M) framework for saturated soil layers is proposed, incorporating a generalized consolidation framework and Darcy's law, both of which account for the impact of fixed charges. The established model is then used to explore the coupled behavior of a saturated soil layer under different fixed charge conditions. Results show that as the cation exchange capacity (CEC) increases, both the dissipation time of excess pore fluid pressure along with settlement stabilization time extend. With an increase in the CEC value, the rate of solute transport decelerates, leading to a distinct prolongation of the breakthrough time. In particular, when CEC increases from 10 to 70 mmol/100 g, the breakthrough time is extended by 13.2 years. That is, the proposed model successfully reveals the effect of fixed charges upon the C–H–M coupled performance of soil layers. The proposed model offers a precise tool for the design and operational assessment of landfill barriers. [ABSTRACT FROM AUTHOR]

• Satisfaction degree of consumers is adopted for seismic resilience assessment. • Recovery-based resilience enhancement strategies of water distribution networks is studied. • Importance-based, damage-based and distance-based recovery strategies are compared. This study investigates different pipe recovery strategies of water distribution networks (WDNs) from the seismic resilience perspective. A demand-based seismic resilience index (SRI) is defined to reflect the system performance level during the post-earthquake recovery process, which is characterized by the satisfaction degree of consumers. Then, a pipe fragility model based on the Chinese code is employed to determine the pipe damage conditions subjected to earthquakes. Taking the WDN in Mianzhu city as an example, three pipe recovery strategies, i.e., static importance-based strategy, damage-based strategy, and distance-based strategy are compared using the Monte Carlo simulation. After comparing the recovery trajectory of system satisfaction degree and the final SRI , the static importance-based strategy is proved to be the best among the three, especially in the early recovery stage. In addition, the dynamic importance-based strategy and the optimal strategy obtained by the genetic algorithm are discussed in a deterministic way. Results show that although the two strategies improve the seismic resilience of WDNs, the computation cost is high due to the time-consuming nonlinear hydraulic analysis. Compared with them, the static importance-based strategy is still a good one in terms of computational efficiency and high SRI value. [ABSTRACT FROM AUTHOR]

• We study the lifecycle operational resilience framework of water distribution networks. • The proposed framework considers daily accidents, pipe deterioration and restoration. • The disruptions are simulated by leakages and bursts based pipe accidents. • The proposed framework is applied to study a real system in city Mianzhu. • Six resilience strategies are investigated to conclude resilience enhancement guidance. This paper proposes a lifecycle operational resilience assessment framework of urban water distribution networks (WDNs), taking accidents, pipe deterioration, and restoration into account. First, the accident occurrence rates for three common types of pipes, namely, cast iron pipes (CIPs), ductile iron pipes (DIPs), and steel pipes (SPs), are fitted using the maintenance data provided by a water administrative sector. Second, for the two most common accidents, i.e., leakages and bursts, the accident pipes in the former case are simulated by reduced flow, while the accident pipes as well as the influenced ones in the latter case are isolated completely by closing valves, which are determined by a depth-first search method. Third, two restoration strategies are considered, including plugging and replacement, and the corresponding recovery time by days are given based on the maintenance data. Meanwhile, the aging induced pipe deterioration is modeled in the operation process. Finally, the operational resilience of the WDN in Mianzhu city is evaluated by above framework and six resilience strategies are investigated and compared. Results show that replacing accident pipes with new DIPs once burst occurs improve the operational resilience of WDNs most obviously. In addition, replacing CIPs with DIPs ahead of the design working life or adding valves also help to improve the resilience level. Based on the findings, some feasible and practicable resilience enhancement suggestions are concluded to provide guidance for local decision makers. [ABSTRACT FROM AUTHOR]

• We review the literatures on the six urban critical infrastructure networks (CINs). • For the six CINs, the resilience definitions, hazard categories, methodologies, and enhanced measures are summarized in detail. • The research challenges and future directions are presented. With the rise of the resilience concept, scholars and practitioners have paid increasing attention to resilient city, which has become a new means of coping with hazards. As the cornerstone of modern cities, urban critical infrastructure networks (CINs) are prerequisites for resilient cities due to the huge economic losses and social impacts caused by their incapacities. In recent years, researches on the resilience of CINs have considerably increased, resulting in various resilience definitions, approaches, and enhanced strategies. This work reviews literature on six CINs, namely, water, drainage, gas, transportation, electric, and communication networks. The resilience definitions, hazard categories, methodologies, and enhanced measures for each CIN are analyzed in detail. Research challenges and future directions are also presented. [ABSTRACT FROM AUTHOR]

In this study, a lifecycle operational reliability assessment framework for water distribution networks (WDNs) is proposed on the basis of the probability density evolution method (PDEM). The occurrence models of daily accidents are fitted using the maintenance data provided by a local water administration sector. For a given accident, two types of accidents (e.g., leaks and bursts) are distinguished in different occurrence probabilities and simulated in various ways. The pipe deterioration process in the lifecycle is reflected by incorporating the time-dependent pipe roughness model. Considering various randomness in the model, PDEM, a newly proposed and developed method for a stochastic system, is used to evaluate the lifecycle operational reliability of WDNs. The framework is demonstrated using an actual WDN, and the nodal reliabilities in the lifecycle are obtained. Comparisons of the operational reliabilities of all nodes calculated via the PDEM and Monte Carlo simulations prove that PDEM is an accurate and highly efficient method. • Accident and deterioration models is established for WDNs. • The operational reliability of WDNs is evaluated based on the PDEM. • The accuracy and efficiency of PDEM is illustrated by the comparison between MCS. [ABSTRACT FROM AUTHOR]

The demand for smart packaging to monitor food spoilage is increasing. In the present study, composite anthocyanin microcapsules (CAM) were prepared by using zein and gellan gum as wall materials and protecting composite anthocyanin (CA). Carrageenan (Car)/sodium carboxymethylcellulose (CMC)-based indicator films (CC) containing CAM microcapsules were developed for monitoring the freshness of beef. The results demonstrated that the composite anthocyanins could be well dispersed in the CC matrix. CAM significantly reduced the effects of light and temperature on the stability of anthocyanins. CAM significantly improved the thermal stability, barrier properties and tensile strength of the films. The infrared spectra showed that the components of the indicator films were structurally similar and well-compatible. Among them, the indicator film CC/CAM-3 had the highest tensile strength (17.76 MPa), the lowest water vapor transmission rate (1.35 × 10−11 g/m·s·Pa) and a tight and neat cross-section. The color of the indicator film changed significantly in the ammonia environment: pink→blue-green→yellow. Applying different concentrations of indicator films to beef freshness monitoring, we found that beef reached sub-freshness and spoilage on days 4 and 7, respectively, and accordingly the indicator film CC/CAM-3 changed from pink to purple and green. To examine its capability as a colorimetric indicator film, we related the change in beef quality to the ΔE value of the indicator film, which proved to be the most sensitive when used to monitor the freshness grade of beef, as demonstrated by the indicator film CC/CAM-3. [Display omitted] • DFPP as co-colorants combined with microencapsulation to improve the stability of PKA. • CAM reduced the effects of light and temperature on the stability of anthocyanins. • CAM improved the thermal stability, compatibility, barrier and mechanical properties of the film. • The color of the film changed in the ammonia environment: pink.→blue-green→yellow. • Indicator strips: fresh meat—pink, sub-fresh meat—grey-purple and spoiled meat—green. [ABSTRACT FROM AUTHOR]

The membrane efficiency coefficient is a critical theoretical indicator used to assess the performance of clay barriers in landfills. At present, the membrane efficiency coefficient is determined in response to a single ion, which cannot be used to accurately evaluate the performance of clay barriers under multiionic leachates. Therefore, a membrane efficiency model must be developed considering multiionic conditions. In this study, a membrane efficiency model of clay under multiionic conditions is established based on the mineral–pore fluid interactions and triple-layer model. The proposed model is validated by comparing the predicted and measured results of the variation in membrane efficiency coefficients with mixing ratios under multiionic conditions. Results indicate the proposed model accurately determines the membrane efficiency of clay under multiionic conditions. The predicted membrane efficiency coefficient decreases with increasing solution concentration and void ratio due to the weakened mineral-pore fluid interaction. The proposed membrane efficiency model can provide a more accurate theoretical tool to assess the performance of clay barriers. • The soil water interaction is considered in the membrane efficiency model. • Membrane efficiency under multiionic conditions is considered in the model. • Membrane efficiency of clay under multiionic conditions is well predicted. [ABSTRACT FROM AUTHOR]

An accurate and efficient reliability evaluation is necessary for network systems with uncertain conditions, especially for the lifeline networks subjected to earthquakes. This study takes gas supply networks as examples and establishes an approach to evaluate the seismic reliability of networks on the basis of the probability density evolution method. First, a nonlinear finite element model is established to simulate buried pipe networks that are subjected to earthquakes. Then, the seismic stresses of the pipes are derived, and the von Mises stresses of the pipes are calculated and used to judge pipe failure. Second, a connectivity index is defined to describe the connectivity between the source and the terminal. Third, on the basis of the probability density evolution method, network reliability is obtained after introducing a physically-based model to simulate ground motion field. Finally, two networks are used as examples to demonstrate the proposed approach, and the results are validated by the Monte Carlo simulation method and compared with a selective recursive decomposition algorithm. [ABSTRACT FROM AUTHOR]

[Display omitted] • Domestication of bacteria by MNBs was proposed for bacteria optimization. • Phenol degraded dramatically from 1000 to 23.84 mg L−1 within 10 h in MNB-AR. • MNB-AR achieved high COD removal efficiency (over 92%) in a high-COD environment. • MNB-AR maintained excellent stability under severe water quality fluctuations. • Functional microbials and genes related to phenol degradation were upregulated. The treatment of coking wastewater with high phenol concentrations has been a challenge for conventional biological treatment technology. In this short communication, phenol-degrading bacteria domesticated by micro and nano bubbles (MNBs) water are used to treat the high- concentration phenol in an MNBs aeration reactor (MNB-AR). The results show that the MNB-AR can greatly improve the removal of phenol and chemical oxygen demand (COD). At a phenol concentration of 1000 mg L−1, the phenol and COD removal rates in the MNB-AR are 55 % and 39 % higher than in the conventional bubble aeration reactor respectively. MNB-AR performs more stably and reaches a higher phenol tolerance under fluctuating high-phenol-concentration loadings. Metagenomic analysis shows that MNBs promote the growth and metabolism of aerobic microorganisms related to phenol degradation, and enhance gene abundance related to carbon metabolism. MNBs aeration combined with microorganisms is an efficient solution for treating coking wastewater. [ABSTRACT FROM AUTHOR]

• A series of centrifuge tests of large diameter steel pipes crossing strike-slip faults are conducted. • Pipe ovalization rate is accurately measured for the first time. • Factors influencing the responses of steel pipes crossing faults are investigated. • Different failure modes of buried steel pipes are discussed. Fault rupture is one of the main hazards for buried continuous pipes, and it has frequently been investigated experimentally in recent decades. In this study, to explore and model the failure mechanisms of continuous steel pipes crossing faults, a series of centrifuge tests of large-diameter steel pipes (D = 1.616 m) crossing strike–slip faults was conducted. Pipe strains are measured using 30 strain gauges, and pipe cross-section deformation is determined using a micro industrial endoscope for the first time; thus, cross-sectional ovalization is accurately derived. Subsequently, factors influencing the responses of steel pipe crossing faults, such as the burial depth, pipe-fault crossing angle, and pipe diameter, are investigated. The centrifuge test results show that the pipe responses, including the pipe strain and deformation, are significantly affected by these factors. Finally, three limit states are considered and compared: 3 % tensile strain, 15 % cross-sectional ovalization, and local buckling limit, and pipe failure behaviors are examined for these cases. The results shown that these tests can serve as benchmarks for theoretical and numerical models. [ABSTRACT FROM AUTHOR]

Large-scale nanofiltration (NF) membrane fabrication relies on the use of harmful solvents and dangerous monomers (e.g. , piperazine and trimesoyl chloride). Herein, we employed greener polydopamine (PDA) and polyethyleneimine (PEI) co-deposition to construct NF selective layer on poly(vinyl chloride) (PVC) substrate prepared by using the green solvent methyl-5-(dimethylamino)-2-methyl-5-oxopentanoate (PolarClean). The metal-organic framework (MOF) UIO-66 was also co-deposited to tune the NF selective layer property by exploiting hydrogen bonds, Π-Π interaction, and coordination bonds between oxygen functional groups and zirconium (Zr) of UIO-66 and the PDA-PEI complex, as well as its intrinsic properties of high hydrophilicity and positive charge. It also improved the surface area of NF selective layer, contributing to higher permeability. However, excessive dosage, higher than 0.1 g/L, promoted PDA aggregation, thus reducing its deposition on membrane surfaces and causing defects. When the dosage was 0.05 g/L, the ternary coated NF membrane exhibited the best property with low molecular weight cut-off (MWCO, ∼350 Da), adequate hydrophilicity, high permeance (3.17 ± 0.3 L m−2 h−1 bar−1), and high MgCl 2 rejection (>80%). When used for shale gas wastewater (SGW) treatment, the ternary coated membrane showed removal rates of 58.5% for dissolved organic carbon, 71.1% for fluorescent organics, and 6.2% for total dissolved solids, allowing the effluent to meet the standards of SGW internal reuse. This work helps to inspire the next-generation sustainable NF membrane fabrication. [Display omitted] • Sustainable NF membrane was designed using green solvent PolarClean. • The selective layer was fabricated by the ternary coating of PDA/PEI/UIO-66. • UIO-66 optimized the active layer properties by forming hydrogen bonds and chemical bonds with PDA-PEI. • Ternary coated membranes were applied for SGW treatment. • Ternary coated membrane showed better antifouling properties than commercial ones. [ABSTRACT FROM AUTHOR]