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Discovering macromolecules and understanding the associated mechanisms involved in underwater adhesion are essential for both studying the fundamental ecology of benthos in aquatic ecosystems and developing biomimetic adhesive materials in industries. Here, we employed quantitative proteomics to assess protein expression variations during the development of the distinct adhesive structure - stolon in the model fouling ascidian, Ciona robusta. We found 16 adhesive protein candidates with increased expression in the stolon, with ascidian adhesive protein 1 (AAP1) being particularly rich in adhesion-related signal peptides, amino acids, and functional domains. Western blot and immunolocalization analyses confirmed the prominent AAP1 signals in the mantle, tunic, stolon, and adhesive footprints, indicating the interfacial role of this protein. Surface coating and atomic force microscopy experiments verified AAP1′s adhesion to diverse materials, likely through the specific electrostatic and hydrophobic amino acid interactions with various substrates. In addition, molecular docking calculations indicated the AAP1′s potential for cross-linking via hydrogen bonds and salt bridges among Von Willebrand factor type A domains, enhancing its adhesion capability. Altogether, the newly discovered interfacial protein responsible for permanent underwater adhesion, along with the elucidated adhesion mechanisms, are expected to contribute to the development of biomimetic adhesive materials and anti-fouling strategies. Discovering macromolecules and studying their associated mechanisms involved in underwater adhesion are essential for understanding the fundamental ecology of benthos in aquatic ecosystems and developing innovative bionic adhesive materials in various industries. Using multidisciplinary analytical methods, we identified an interfacial protein - Ascidian Adhesive Protein 1 (AAP1) from the model marine fouling ascidian, Ciona robusta. The interfacial functions of AAP1 are achieved by electrostatic and hydrophobic interactions, and the Von Willebrand factor type A domain-based cross-linking likely enhances AAP1's interfacial adhesion. The identification and validation of the interfacial functions of AAP1, combined with the elucidation of adhesion mechanisms, present a promising target for the development of biomimetic adhesive materials and the formulation of effective anti-fouling strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Antifouling membranes were developed by encapsulating amino-functionalized nano-silica in polymeric mixes of polyethersulfone (PES) and polyvinyl pyrrolidone (PVP). Subsequently, the membranes were modified with a nano-Ag/PVP coating layer. The membranes' performance was assessed against synthetic whey solutions model to mimic dairy wastewater. Various techniques were harnessed to evaluate the membranes' composition, structure and morphology, including SEM, XPS, XRD, AFM, mechanical characteristics, porosities and contact angles. Findings indicated that nanocomposite made with 1.5 % amino-functionalized nano-silica (M3) revealed optimum performance and was capable to separate 90 % of the whey in the feed along with a permeate flux of 238 L/m2.h, when the feed whey concentration was 0.4°Brix. the equivalent membrane but coated with a nano-Ag /PVP layer (M3S) displayed a trivial drop in permeate flux (229.3 L/m2.h) comparing to uncoated one. Nonetheless, the addition of the coating boosted the separation efficiency up to 99.7 % of the whey in the feed. The fouling test indicated that the coated membrane (M3S) had superior antifouling property, where flux recovery ratio (FRR) hit 99.5 % with a diminution in the backwash rate. [ABSTRACT FROM AUTHOR]

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Copyright of Rudarsko-Geolosko-Naftni Zbornik is the property of Faculty of Mining, Geology & Petroleum Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Key Takeaways: The expanding use of reverse osmosis (RO) in water treatment beyond desalination is benefiting from improved methods and technologies. Conventional RO membrane autopsies are conducted to identify causes of membrane fouling, assess membrane condition, and determine ways to address challenges. Advanced membrane forensics aid in broadening RO applications, ensure system effectiveness, and can result in cost savings by extending membrane element life. [ABSTRACT FROM AUTHOR]

In this study, a multifunctional poly(vinylidene fluoride) (PVDF) membrane was developed through chemical binding with ZnO-Ag nanocomposites to increase wastewater treatment efficiency. The unique characteristics of ZnO-Ag nanocomposites endowed the membrane with high surface hydrophilicity, organic/bio fouling resistance, and photocatalytic antibacterial activity. The significantly decreased water contact angle and increased under-water oil contact angle suggested improved surface hydrophilicity and organic fouling resistance. Through factorial analysis, it was found that the antibacterial activity of the multifunctional membrane could be significantly improved under visible light condition and with ZnO-Ag nanocomposites which obtained under higher Ag concentration and sintering temperature. The increase of Ag composition of ZnO-Ag nanocomposites on modified membrane surface significantly improved the membrane antibacterial activity but had little effect on membrane hydrophilicity. In addition, the photocatalytic antibacterial activity of ZnO-Ag nanocomposites could further improve the membrane biofouling resistance through simple exposure to visible light. The effects of different Ag chemical states on the performances of ZnO-Ag nanocomposites and the corresponding modified membranes were studied, and the relevant mechanism of antibacterial activity under both dark and light conditions was discussed. Filtration experiments with secondary wastewater effluent as feed solution indicated that the developed membrane exhibited one order of magnitude larger permeate flux compared to the pristine PVDF membrane, while maintaining comparable bacteria rejection rates during the filtration process. [ABSTRACT FROM AUTHOR]

A considerable hindrance in application of ultrafiltration membranes for aqueous application is an occurring fouling which promotes deterioration of the membrane separation processes. Natural Olea europaea leaves extract nanosolids embed in cellulose acetate polymer matrix to enhance anti-biofouling properties of ultrafiltration membrane. Olea europaea phenolic compounds extracted by using Microwave-assisted Extraction (MAE) method and evaporated to obtain nanosolid particles. The cellulose acetate/ Olea europaea nanosolids (CA/OEN) membrane composite prepared using phase inversion method. The membrane properties evaluated in term of mechanical, mass transport and anti-biofouling properties. The membranes show a good mechanical property with the membrane tensile ranged within 3.3 N/mm2 and 6.8 N/mm2, and can acts as ultrafiltration composite membranes based on the pure water transport across the membrane, with the pure water flux ranged from 0.3 L/m2.h.bar to 0.9 L/m2.h.bar. In term of anti-biofouling properties, the membrane shows a good anti-biofouling property against Escherichia coli, Bacillus subtilis , and Staphylococcus aureus , with the percentage of area covered by bacteria are ranged between 0.39 % and 1.41 %. Yet, penetration of phenolic substance into bacterial cells could effectively occurred in a Gram-negative bacterium such as Escherichia coli due to low affinity, thin cell wall, and few peptidoglycans structure. [ABSTRACT FROM AUTHOR]

Key Takeaways: Desalination is a widely used process in the universal drive to create new water supplies, with systems frequently turning to reverse osmosis (RO) as an affordable treatment technology. Intelligent water models, which use advanced algorithms to analyze large amounts of diverse data, can work in tandem with membrane forensics to boost RO systems' efficiency. Membrane fouling is a prime candidate for the benefits of intelligent water technologies, which could allow for real‐time analysis and control. Machine learning could gain a foothold in water treatment as its capabilities evolve and applications are understood and accepted. [ABSTRACT FROM AUTHOR]

Classification is an essential task for many applications, including text classification, image classification, data classification, and so on. The present study investigates the accuracy of different machine learning classification algorithms with three different data smoothing techniques for gas turbine fault detection and isolation task. The gas turbine performance model was developed by considering variable inlet guide vane and bleed air. Fouling and erosion were injected into all six main components of the gas turbine engine. Faulty and non-faulty data were generated from the developed performance model. Based on sensitivity analysis, 12 measurement parameters and 11,824 data points were selected for the development of a fault detection and isolation model. The faulty and non-faulty data were balanced, smoothed, corrected and normalized. Finally, the classification accuracy of the machine learning techniques was analyzed. The result shows that K-Nearest Neighbours, Neural Network and Decision Tree classifiers exhibited high classification accuracy, about 99% with all three data smoothing techniques. It is also observed that the computation time of Support Vector Machine is higher whereas K-Nearest Neighbours shows the lowest. Finally, the research proves that K-Nearest Neighbours is the best classification technique for gas turbine engine fault detection and isolation application. [ABSTRACT FROM AUTHOR]

Marine biofouling is considered one of the major biophysical processes influencing the vertical dynamics of plastic debris in seawater. We numerically implement, for the first time, this mechanism within a fine-resolution, regional model of the Tyrrhenian Sea, in order to simulate the dispersion of microplastics (MPs) released at the mouth of a highly polluting river. Four polymers and three particle sizes are used to quantify algal concentration influence on the trajectories, fates, and accumulation spots of the tracked MPs, by comparing 2002 winter and summer runs encompassing or not biofouling. Besides a marked seasonality for most of the MP types and radii tested, biofouling effects are prominently observed for only 2 polymers and particles bigger than 1 μ m. Thus, further realistic applications of the biofouling mechanism in oceanic circulation models are required to achieve a thorough assessment of its impact on plastic density within distinctive basins of the world seas. • Marine biofouling is explicitly resolved in a realistic regional model (ROMS). • Microplastic (MP) particles are released at the outlet of a highly polluted river. • Biofouling strongly affects the horizontal and vertical dispersion of MPs. • Biofouling effects are significant for a limited range of MPs' sizes and polymers. • A marked seasonality is observed in the biofilm growth over the MP particles. [Display omitted] [ABSTRACT FROM AUTHOR]

In recent years, environmental and ecological issues caused by microplastics pollution have received widespread attention. The coexistence of polyethylene (PE) microplastics with other soluble and particulate contaminants in water environments is considered to pose a new challenge for water treatment engineering. This study first focused on the combined effects of microplastic size (13 and 150 μm) and concentration (0, 20 and 100 mg/L) of floc properties in the coagulation-flocculation process (CF). The results showed that the involvement of PE microplastics hindered larger floc formation but enhanced the floc strength. The presence of either smaller microplastic particles at a fixed concentration (100 mg/L), or a higher concentration of 13 μm microplastic particles resulted in smaller and more highly-branched floc aggregates. During ultrafiltration of pre-coagulated water (CF-UF), the "13 μm + 100 mg/L" case exhibited less severe membrane fouling than the other cases ("without PE", "13 μm + 20 mg/L" and "150 μm + 100 mg/L"). Comparing the CF-UF process in the "without PE" and "13 μm + 100 mg/L" cases, the pre-deposited aggregate-based layer could give a lower degree of membrane flux decline and mitigate membrane fouling during ultrafiltration of pre-coagulated water (CF-UFPL). Moreover, both the involvement of PE microplastics and the properties (thickness and compactness) of the pre-deposited layer affected membrane filterability and fouling degree. Lastly, the influencing mechanisms of coexisting microplastics in UF, CF-UF and CF-UFPL processes were explored by comparatively analyzing the correlation of pre-coagulated floc physicochemical characteristics with membrane filterability, water purification efficiency and membrane fouling degree in both the absence and presence of microplastic particles. [Display omitted] • Effects of PE particle size and concentration on the floc formation were evaluated. • The pre-deposited layer thickness and compactness affected membrane fouling degree. • CF-UFPL outperformed UF and CF-UF in fouling mitigation and treated water quality. • The influencing mechanism of PE in cake layer formation was comparatively explored. • This study favors the use of UF-based process in treating water with microplastics. [ABSTRACT FROM AUTHOR]

• Recovery rate of Ca2+, Mg2+ and SO 4 2– reached 90 %, 99 % and 50.2 %, respectively. • TOC and UV 254 can be effectively decreased with 36.6 % and 59.6 % removal rates. • The AEM electrolysis was optimized to 10 mA/cm2, whereas the CEM was to 15 mA/cm2. • The AEM fouling was more serious than the CEM due to the distinct fouling types. In this study, a hybrid ion exchange membrane (IEM) electrolysis process incorporating AEM/CEM electrolysis was implemented to investigate the removal efficiency and the underlying mechanism of IEM fouling in removing organic matter and ions (Ca2+, Mg2+, SO 4 2–) from nanofiltration concentrate (NFC). The results reveal that Ca2+ and Mg2+ were removed through the formation of CaCO 3 and Mg(OH) 2 precipitates in the cathode chamber of AEM electrolysis (ACC), whereas SO 4 2– was enriched in the anode chamber (AAC). The addition of Ca(OH) 2 and NaAlO 2 led to ettringite precipitation in the cathode chamber of the CEM electrolysis (CCC), along with CaCO 3 and Mg(OH) 2 precipitates. Meanwhile, the oxidation and the precipitation adsorption led to effective removal of organic matter. A comparison of the current density demonstrated that the optimum conditions for removal were 10 mA/cm2 in AEM electrolysis and 15 mA/cm2 in CEM electrolysis. Notably, in IEM fouling, the Zeta potential, XDLVO and other results showed the AEM fouling was more aggravated than CEM. [Display omitted] [ABSTRACT FROM AUTHOR]

The reverse osmosis seawater desalination plants open-intake requires different strategies of pre-treatment to reduce the biofouling and scaling. The UltraFiltration (UF) technology is a recent application to this process. In this work, some alternatives to chemical products reducing in chemically enhanced backwash (CEB) and clean in place (CIP) of a UF rack have been studied. Mainly the sodium hypochlorite consumption, due to its biofouling precursor effect over reverse osmosis membranes. For this purpose, the optimal filtration time has been studied, to get the highest water production prior to the CIP, as well as some modifications in the conventional CIP's, modifying the duration of the stages of the same. The results were compared with the current mode of daily operation of the CEB. The results show that a reduction of up to 60% in the amount of sodium hypochlorite per cubic meter of water produced employed in UF CEB's, mini CIP's and CIP's can be achieved. However, the consumption of the rest of chemical dosing increased notably, and therefore the operating cost of UF also increased. In addition, there was an increase of desalted water consumption to the chemical products removed, up to almost 95,84 %, in comparison with the currently operational mode of CEB. On the other hand, operating the UF plant in the manner proposed requires a automatization of the process and expert staff to programme the control. Therefore, based on the results obtained, the alternatives proposed could reduce the chemical products in use, but it is not conclusive in terms of exploitation operational costs. [ABSTRACT FROM AUTHOR]

Biodegradable microplastics (MPs) can form biofilms through interactions with various microorganisms in aquatic system and can be exposed to organisms. This study first investigated biodegradability of polylactic acid (PLA) MPs and the characterization of PLA MPs before/after biofouling (4 weeks) and their toxic effects on the freshwater invertebrate Daphnia magna. The biodegradability rate of PLA MPs was up to 50% over 28 days, suggesting that even biodegradable MPs do not easily decompose under environmental conditions. Furthermore, biofouling of MPs led to an increase in size and, in the process, induced an additional functional peak in the PLA MPs. The exposure of biofouled MPs did not lead to a reduction in survival, reproduction, or growth during chronic exposure, nor did it cause feeding inhibition in juvenile (<4 days old) D. magna. However, pristine MPs significantly reduced survival, reproduction, and growth at concentrations of 5.0 mg L−1. Overall, pristine MPs caused inhibition of reproduction and growth and high mortality in D. magna , while the biofouling process did not induce these effects. Our findings highlight the complex interactions between MPs and biological components in aquatic environments, emphasizing the importance of considering biofouling dynamics when assessing the ecological impacts of biodegradable MPs. [Display omitted] • Pristine PLA MPs are not readily biodegradable within 28 days in aquatic environments. • Biofouling in WWTP sludge over 28 days led to the aggregation and increased size of PLA MPs. • The toxicity of Biofouled PLA MPs lower than pristine PLA MPs over a chronic exposure. • Biofouled PLA MPs do not induce oxidative stress to D. magna over a chronic exposure. [ABSTRACT FROM AUTHOR]

Recreational bathing waters are complex systems with diverse inputs from multiple anthropogenic and zoogenic sources of faecal contamination. Faecal contamination is a substantial threat to water quality and public health. Here we present a comprehensive strategy to estimate the contribution of faecal indicator bacteria (FIB) from different biological sources on two at-risk beaches in Dublin, Ireland. The daily FIB loading rate was determined for three sources of contamination: a sewage-impacted urban stream, dog and wild bird fouling. This comparative analysis determined that the stream contributed the highest daily levels of FIB, followed by dog fouling. Dog fouling may be a significant source of FIB, contributing approximately 20 % of E. coli under certain conditions, whereas wild bird fouling contributed a negligible proportion of FIB (<3 %). This study demonstrates that source-specific quantitative microbial source apportionment (QMSA) strategies are vital to identify primary public health risks and target interventions to mitigate faecal contamination. [Display omitted] • Source-specific QMSA is vital to quantify diverse biological sources of faeces. • Sewage-impacted stream contributed the highest daily FIB loading onto beaches. • Dogs were estimated to load 0.6 –h 2.2 kg of faeces and 20 % of E. coli daily. • Wild bird fouling contributed a negligible proportion of FIB. [ABSTRACT FROM AUTHOR]

• Bandgap tuning of TiO 2 by CuO nanoparticles for improved photocatalytic activity. • Photocatalytic mechanism confirmed by the major contributions of h + and e − agents. • Under UV + PMS conditions, photocatalytic efficiency reaches the highest at 90%. • Membrane antifouling ability showed an FRR of 98.8% and lower surface roughness. • Membrane hydrophilization by O 2 plasma and PAA layer showed enhanced pure water flux. One direction to mitigate membrane fouling is to create anti-fouling photocatalytic membranes. The photocatalysts' hydrophilicity reduces the interaction of the membrane with hydrophobic foulants and the photocatalysis decomposes membrane fouling. Another noteworthy point is that PMS (peroxymonosulfate) can be activated by photocatalysts to decompose foulants and membrane fouling more intensely. The CuO/TiO 2 was prepared by deposition of Cu(OH) 2 onto TiO 2 followed by heat treatments. Their catalytic performances were tested by the degradation of Acid Blue 260 by photocatalysis and PMS activation. The best CuO/TiO 2 was then coated onto PVDF membranes through a PAA binding layer. Their antifouling performance was examined through simulated foulants such as sodium alginate. The photocatalysts and membranes were characterized using FTIR, SEM-EDS, TEM, XRD, BET, UV–Vis DRS, XPS, ESR, and AFM. The CuO/TiO 2 possessed a lower bandgap, high surface area (60.7 m2/g), and low particle sizes (30–60 nm). The 25%CuO/TiO 2 possesses the highest photocatalytic degradation efficiency of 39.0% under UV irradiation; further PMS activation caused the removal efficiency to reach 90.0%. The degradation efficiency by the membrane was 100% after five cycles. The membranes indicated a decrease of 18.9% in water flux but remained very high. The membrane flux recovery ratio (FRR) was 98.8%. [Display omitted] [ABSTRACT FROM AUTHOR]

• Fouling cycle was prolonged significantly by d-tyrosine. • EPS in activated sludge were effectively inhibited by d-ribose. • D-ribose promote CAT and SOD activity of activated sludge, and reduce MDA. • Long-term addition of d-ribose could increase the abundance of QQ bacteria. Membrane biofouling is still one major obstacle in the application of membrane bioreactor (MBR). Because of similar chemical structure to quorum sensing (QS) signaling molecule autoinducer-2 (AI-2), D-ribose might be an ideal QS inhibitor to inhibit membrane biofouling. 100 μM of D-ribose were periodically added to MBR to investigate the effect of D-ribose on membrane biofouling in MBR. The fouling cycle was prolonged significantly, and the membrane was covered with larger and looser foulants with the addition of D-ribose. The soluble microbial products (SMP) content were reduced slightly and the secretions of extracellular polymeric substances (EPS) in activated sludge were effectively inhibited by the addition of D-ribose. Moreover, D-ribose could promote catalase (CAT) and superoxide dismutase (SOD) activity of activated sludge, and reduce the accumulation of malondialdehyde (MDA). Furthermore, long-term addition of D-ribose could increase the abundance of quorum-sensing quenching (QQ) bacteria, strengthen the quenching ability of the system and effectively inhibit membrane biofouling. [Display omitted] [ABSTRACT FROM AUTHOR]

Inorganic-organic contaminants in mine wastewater treatment constantly challenge the performance of reverse osmosis (RO) membranes. In this work, the main pollutants are calcium ions, soluble silicate, and fulvic acid (FA). We investigate the membrane contamination response of these contaminants in single cases and several composite scenarios. It turns out that membrane fouling is significantly affected by differences in feed composition and content. When all three contaminants coexist, the Lewis acid-base (AB) interaction may dominate the contamination process. When the Ca2+ concentration was raised from 0 to 7 mM, the AB energy between foulants decreased from −77.47 KT to −98.84 KT at the minimum separation distance. This study highlights the impact of typical inorganic and organic pollutants in the RO process, which could help optimize feed conditions while also giving a comparable theory for the water treatment sector. [Display omitted] • Membrane fouling behavior under various RO feed conditions. • The presence of Ca2+ with FA or silicates induces distinct membrane fouling behavior. • The presence of Ca2+ worsen membrane fouling by decreasing electrostatic repulsion. • Changes in AB interface interactions dominate the evolution of membrane fouling. [ABSTRACT FROM AUTHOR]

To address the significant challenge of biofouling in ultrafiltration (UF) membranes, primarily caused by bacteria during water purification, we have developed an innovative light-responsive active self-cleaning membrane (TA@Fe-TiO 2 /PVDF). This membrane is produced by coating polyvinylidene fluoride (PVDF) with a metal-polyphenol-based complex (TA@Fe-TiO 2 MPN). Compared to traditional photocatalytic membranes, such as TiO 2 /PVDF, the TA@Fe-TiO 2 /PVDF self-cleaning membrane demonstrates superior anti-biofouling and self-cleaning properties, achieving nearly complete flux recovery (∼100%) and bactericidal efficiency (close to 100%) in the treatment of municipal secondary effluent without the need for chemical additives. This effectiveness is attributed to the generation of hydroxyl radicals (·OH) and singlet oxygen (1O 2) when the membrane is exposed to light, enhanced by the significant photothermal performance of TA@Fe. Notably, the TA@Fe-TiO 2 /PVDF membrane also excels in removing antibiotic resistance genes (ARGs), such as tetracycline and sulfadiazine , from wastewater. The removal of bacteria and ARGs is facilitated by a self-cleaning mechanism that combines partial mineralization and oxidation, as evidenced by increased hydrophilicity, active oxygen sites, and electron transfer. The membrane's efficient light-responsive excitation, self-cleaning capability, and stability herald new avenues for the sustainable application of membrane technology in water purification, characterized by reduced energy demands. [Display omitted] • Novel TA@Fe-TiO 2 /PVDF membrane combats biofouling in ultrafiltration. • Achieves ∼100% flux recovery and bactericidal efficiency without chemicals. • Light exposure activates self-cleaning via hydroxyl radicals and singlet oxygen. • Efficiently removes antibiotic resistance genes, enhancing water safety. • Merges photothermal performance with photocatalysis for sustainable purification. [ABSTRACT FROM AUTHOR]

Considering the worldwide water scarcity issue, membrane distillation (MD) offers a promising solution for producing reclaimed water from secondary effluent generated by municipal wastewater treatment plants. However, prolonged operation of MD systems can result in membrane fouling, which impairs separation efficiency and shortens the membrane's lifespan. To overcome these challenges, novel surface-modified polytetrafluoroethylene (PTFE) membranes have been developed through a combination of polydopamine deposition and quaternary ammonium compound (QAC) grafting (named as PDQ membranes). The objectives of this preparation are to reduce the membrane hydrophobicity, impart anti-adhesive and bactericidal properties, and improve water permeability and antifouling performance in the MD system. In particular, the membrane coated by a QAC solution with the concentration of 40 mM (named as M3 membrane), achieved a flux of 47.0 LMH, surpassing the original PTFE membrane by 11.4%. During the long-term direct contact membrane distillation operation with the secondary effluent, the M3 membrane exhibited significantly superior antifouling capability than the PTFE membrane. Undergoing three runs of the MD process, the flux reduction of M3 was only 38.1%, whereas the flux of original PTFE membrane experienced a 71.4% decline. The PDQ membranes were also capable of providing stable distillate quality (over 40 h). Notably, the M3 demonstrated a high rejection capability, with an impressive removal efficiency of 96.9% for low molecular weight organics and 92.5% for humus-like substances. Additionally, the PDQ membrane exhibited good anti-bioadhesion and bactericidal properties. This study highlights the promising application potential of the PDQ membrane for fouling mitigation in water and wastewater treatment. [Display omitted] • Polydopamine and quaternary ammonium compound surface-functionalized (PDQ) membranes were successfully fabricated. • Membrane distillation performance of PDQ membranes was investigated. • PDQ membranes exhibited significantly superior antifouling capability. • PDQ membranes were also capable of providing stable distillate quality. • PDQ membranes demonstrated good anti-bioadhesion and bactericidal properties. [ABSTRACT FROM AUTHOR]

This paper describes a simple generic model designed to predict membrane fouling in municipal wastewater (MWW) treatment. The work was conducted using data from a direct membrane filtration demo-system (middle/long-term filtration periods of about 35 – 124 days) to calibrate the model. Two influents were treated by the demo-system: raw pre-treated MWW and primary settler supernatant from a full-scale MWW treatment plant. A resistance-in-series mathematical model structure was proposed considering fouling due to two different mechanisms: persistent cake layer formation (from suspended material) and pore blocking (from soluble and colloidal compounds). The proposed model represented transmembrane pressure dynamics at different operating solids concentrations (around 1, 2.6, 6 and 11 gL−1) using 7 model parameters, achieving 7–28 mbar differences between the experimental data and model predictions in all cases (calculated as the root mean square error). The model was also able to match the results from two different influents (raw MWW and primary settler supernatant) by modifying 3 of the 7 parameters while low uncertainties were obtained in long-term filtrations, demonstrating its robustness. This model thus provides a good potential to generate reasonable membrane fouling predictions while its simple and open structure makes it easy to implement with complementary materials. Further research will be carried out to enhance the model's precision and validate its potential for optimizing filtration and fouling control processes. [Display omitted] • Irreversible fouling from direct sewage filtration was modeled. • Proper predictions are obtained under a simple structure (7 calibration parameters). • Solids (cake layer) and SMP (pore blocking) effects were considered simultaneously. • Two influents were modeled: raw sewage and the primary settler supernatant. [ABSTRACT FROM AUTHOR]

The production of short-chain carboxylates (SCCs) from readily degradable food waste exhibits superior product value compared to biogas production, but SCCs' high solubility poses challenges in their production and recovery. In this study, we applied two novel modules to in-situ extract SCCs from the continuously produced fermentative broth, namely direct coupling of bipolar membrane electrodialysis (BPED) and the integration of upstream membrane permeation (MP) and BPED. The remarkable extraction efficiency of BPED effectively mitigated the inhibitory effects from the accumulation of SCCs products, yielding 475.2 mg gVS−1, which was 20.26% higher than the control phase. The OH− generated by the bipolar membrane was cycled back to regulate the pH of bioreactor, thereby completely eliminating the need for external alkaline additives. The upstream MP effectively prevented ion exchange membrane fouling, and the OH− generated by BPED achieved the in-situ regeneration of MP's alkali extract, reducing the OH− demand by 40% in MP+BPED stage. It was also observed that BPED exhibited higher selectivity towards small-molecule acetic acid, while MP tended to recover larger-molecule caproic acid. Selective extraction of specific SCC drove the product spectrum of the bioreactor to produce more SCC that was selectively extracted. [Display omitted] • In situ BPED extraction increased SCCs yield by 20.26%. • Upstream MP helped to prevent the ion exchange membrane fouling. • The generated OH− by BPED reduced the external base input. • BPED exhibited higher selectivity towards C2 acid while MP towards C6 acid. • Extraction selectivity drove to form a different product spectrum. [ABSTRACT FROM AUTHOR]

Selective serotonin reuptake inhibitors (SSRIs) have been used for decades to treat disorders linked to serotonin dysregulation in the brain. Moreover, SSRIs are often used in studies aimed at measuring serotonin with fast-scan cyclic voltammetry (FSCV) in living tissues. Here, we show that three different SSRIs—fluoxetine, escitalopram, and sertraline—significantly diminish the faradaic oxidation current of serotonin when employing the commonly used Jackson waveform. Coating carbon-fiber microelectrodes (CFMs) with Nafion resulted in further degradation of peak current, increased response times, and decreased background charging currents compared to bare CFMs. To decrease fouling, we employed a recently published extended serotonin waveform, which scans to a maximum positive potential of +1.3 V, rather than +1.0 V used in the Jackson waveform. Use of this waveform with bare CFMs alleviated the decrease in faradaic current, indicating decreased electrode fouling. Collectively, our results suggest that fouling considerations are important when designing FSCV experiments that employ SSRIs and that they can be overcome by using the appropriate waveform. [ABSTRACT FROM AUTHOR]

Detection and responding to a player's affect are important for serious games. A method for this purpose was tested within Chem-o-crypt, a game that teaches chemical equation balancing. The game automatically detects boredom, flow, and frustration using the Affdex SDK from Affectiva. The sensed affective state is then used to adapt the game play in an attempt to engage the player in the game. A randomized controlled experiment incorporating a Dynamic Bayesian Network that compared results from groups with the affect-sensitive states vs those without revealed that measuring affect and adapting the game improved learning for low domain-knowledge participants. [ABSTRACT FROM AUTHOR]

The warning of membrane fouling is of great important to maintain the stable operation of membrane bioreactor (MBR). However, traditional methods are so error-prone that probably do not acquire reliable solutions of membrane fouling due to its uncertainties. To overcome this problem, an intelligent warning method is proposed to monitor the status of MBR in this paper. The main advantages in this paper are as follows. First, an identification method, based on robust deep neural network (RDNN), is developed to diagnose the different types of membrane fouling. Second, a decision-making method, based on the restricted Boltzmann machine (RBM), is designed to distinguish the operational suggestion. Third, an intelligent warning system, based on the above two methods and some sensors, is developed to mitigate the membrane fouling in real wastewater treatment plants. Finally, the simulation and experimental results demonstrate the proposed warning method can obtain the higher identification accuracy of membrane fouling than other methods. [ABSTRACT FROM AUTHOR]

Non-toxic defence against marine biofouling species including invasive species is urgently required. The effect of a synthetic natural compound "1-hydroxy-2-O-acyl-sn-glycero-3-phosphocholine" was tested against larvae of the invasive orange cup coral T. coccinea Lesson, 1829. The larvae were placed in 24-well microtiter plates immediately after their release and subjected to the compound at concentrations of 0.5, 5, 10, 50, and 100 μg mL-1 and three treatments (copper sulfate, solvents, and seawater). Larval mortality ranged from 35% (100 μg mL-1) to 3% (5 μg mL-1), and their average of lethal concentration (LC50) was 142.2 μg mL-1. The results of this study show that compound is a potential option to be applied in the management and control of T. coccinea on artificial structures. [ABSTRACT FROM AUTHOR]

Due to superior energy efficiency and emission-reducing potential, air source heat pumps (ASHPs) have been widely used in space heating and domestic water heating. However, the heating seasons usually coincides with the serious air pollution, hence particulate fouling appears on ASHPs' outdoor coils repeatedly, despite being de-fouled periodically. In this study, four levels of fouling, namely none fouling (0 g/4 m2), mild fouling (15 g/4 m2), moderate fouling (40 g/4 m2) and severe fouling (70 g/4 m2), were concretized on a finned tube heat exchanger successively, followed by experimentally investigating the negative effects of fouling on the heat transfer performance of an air source heat pump water heater (ASHPWH). Results demonstrated that the effects of fouling on the performance of ASHPs in heating mode would be exacerbated with decreased air temperature. In addition, the frosting performances at different levels of fouling were evaluated quantitatively, by depicting the frosting evaluation plots. The frosting evaluating plots suggested that fouling would expand the air temperature and relative humidity (RH) ranges where frosting appears, and would hasten frosting process. As verification, signal factor experiments were carried at different levels of fouling. The experimental results confirmed that the increase of fouling level would result in faster frosting process, but smaller final frost accumulation mass. • Fouling and air temperature have coupled impact on the performance of ASHPs. • The impact of fouling would be intensified in cold regions. • A method was developed to evaluate frosting performance with impact of fouling. • Fouling would expand frosting region and hasten frosting process. [ABSTRACT FROM AUTHOR]

Muskellunge Esox masquinongy are large, predatory game fish whose association with shallow, complex habitats is well documented, particularly during early life stages. Despite this association, relatively little guidance exists regarding effective sampling of Muskellunge larvae and previous efforts to sample larval Muskellunge have been met with limited success. Therefore, our objective was to determine the relative effectiveness of three sampling gears for capturing naturally produced Muskellunge larvae. Larvae were sampled during 2019 and 2020 at known Muskellunge spawning locations in Snipe Lake, Wisconsin, with D‐frame dip nets (1,000‐µm mesh), quatrefoil light traps, and towed ichthyoplankton nets (1,000‐µm mesh). Sixty larval Muskellunge were captured across all gears, and catches in D‐frame dip nets comprised nearly 87% (52 of 60) of the total catch. Furthermore, D‐frame dip nets captured the broadest size range of larval Muskellunge (TL range = 14–33 mm). Greater effectiveness of D‐frame dip nets in comparison with other gears is likely related to their ability to be used in and around structurally complex habitats without fouling or clogging. Our results suggest that D‐frame dip nets should be considered as a cost‐ and time‐effective tool for targeting larval Muskellunge in complex habitats. [ABSTRACT FROM AUTHOR]

• The non-bactericidal films have durable antifouling ability in natural marine environment for 9 months. • Although bactericidal films have anti-adhesion effect under laboratory conditions, but the anti-adhesion effect is not durable. • GSR has lower elastic modulus and compression modulus, which is beneficial to inhibiting bacterial adhesion. Marine biofouling has done great economic damage to people every year, and it seriously affects the development of national economy. In this paper, three types of antifouling films were prepared, including pristine silicon rubber (PSR), graphene added silicon rubber (GSR), and GSR filled with quaternary ammonium salt of different concentrations (QGSR). These antifouling films have strong salt resistance ability, and their surface free energy is in the range of 19.3078 mJ/m2–21.4384 mJ/m2, which is calculated by contact angle. Based on Baier curve, the surface free energy in this zone is benefit to fouling-release. Then, the antifouling ability were explored under both laboratory conditions and real marine environments. Results showed that the bactericidal film of QGSR have antiadhesion effect under laboratory conditions, but the antiadhesion effect is not durable, and it lose antifouling effects completely in real marine conditions. However, the non-bactericidal film of GSR exhibited stronger antifouling ability than QGSR after immersed in marine environment for 9 months. Therefore, the physical interaction to expel bacteria is more conducive to long-term antifouling in the complex marine environment. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Stereochemistry made fun with interactive cards. • Free app for undergraduate chemistry and chemical engineer students. • Multilingual hybrid game, to be played face to face or remotely. • Effective learning tool according to student outcomes. This paper provides information about a hybrid multilingual (English, Portuguese, French, and Italian) game developed as an alternative learning method to the traditional problem-solving exercises model. The game comprises a physical board and a free-of-charge application for undergraduate students to review and reinforce concepts related to stereochemistry by answering questions, from a bank of 400 questions, in a ludic, competitive, and collaborative environment. Brazilian, French, and Italian undergraduate students played the game face-to-face before the disruption caused by the Covid-19 Pandemic and remotely during that. They also evaluated the game, and the quite positive results obtained from students' self-assessment revealed that they felt the game contributed to their learning while playing. [ABSTRACT FROM AUTHOR]

Anaerobic membrane bioreactors (AnMBRs) have garnered considerable attention as a low-energy and low-carbon footprint treatment technology. With an increasing number of scholars focusing on AnMBR research, its outstanding performance in the field of water treatment has gradually become evident. However, the primary obstacle to the widespread application of AnMBR technology lies in membrane fouling, which leads to reduced membrane flux and increased energy demand. To ensure the efficient and long-term operation of AnMBRs, effective control of membrane fouling is imperative. Nevertheless, the interactions between various fouling factors are complex, making it challenging to predict the changes in membrane fouling. Therefore, a comprehensive analysis of the fouling factors in AnMBRs is necessary to establish a theoretical basis for subsequent membrane fouling control in AnMBR applications. This review aims to provide a thorough analysis of membrane fouling issues in AnMBR applications, particularly focusing on fouling factors and fouling control. By delving into the mechanisms behind membrane fouling in AnMBRs, this review offers valuable insights into mitigating membrane fouling, thus enhancing the lifespan of membrane components in AnMBRs and identifying potential directions for future AnMBR research. [Display omitted] • Elevated concentrations of ammonia and phosphate accelerate fouling in AnMBR. • Membrane type and structure are crucial in regulating fouling in AnMBR systems. • Modifications and cleaning are essential for the maintenance of AnMBR. • Effective AnMBR performance necessitates comprehensive fouling management. [ABSTRACT FROM AUTHOR]

Effective and economical marine biofouling protection methods are facing great challenges given the requirements of environmental friendliness and efficiency. Inspired by this, a novel BiOBr/ZIF-67 S-scheme heterojunction photocatalyst with core-shell structure was successfully synthesized by a facile in-situ growth method, where ZIF-67 was uniformly and firmly anchored on the surface of BiOBr microspheres. BiOBr/ZIF-67 composites exhibited excellent removal efficiencies towards typical marine fouling bacteria and microalgae compared with pure ZIF-67 and BiOBr, including Staphylococcus aureus , Escherichia coli , Chlorella sp. , and Phaeodactylum tricornutum. The excellent photocatalytic antifouling performance can be ascribed to the formation of core-shell structure and S-scheme heterojunction, leading to the larger relative surface area, broader visible light response, and enhanced charge separation efficiency. Moreover, a possible photocatalytic mechanism of BiOBr/ZIF-67 S-scheme heterojunction was proposed based on electron spin resonance (ESR) tests, validating the major roles of active species such as ·OH, ·O 2 -, h+, and 1O 2 to attack microorganisms during the photocatalytic process. The density functional theory (DFT) simulated calculations further elucidated the formation of S-scheme heterojunction and the transfer path of electrons and holes in the contact interface. More importantly, a prospective attempt was made by adding BiOBr/ZIF-67 composites into a silicone-based coating to form an antifouling-enhanced coating, presenting a high antibacterial rate and the potential application prospect in marine antifouling. This work provides new insights into fabricating high-performance S-scheme heterojunction photocatalysts for marine antifouling applications. [Display omitted] • Novel BiOBr/ZIF-67 S-scheme heterostructures were synthesized by an in-situ growth method. • BiOBr/ZIF-67 exhibited a highly enhanced photocatalytic antifouling activity. • The S-scheme heterostructure promoted separation of photoinduced charge carriers and maintained stronger redox properties. • h+,·OH,·O 2 -, and 1O 2 played key roles in the photocatalytic reaction for BiOBr/ZIF-67. • An attempt was made by adding BiOBr/ZIF-67 into a silicone-based coating to form an antifouling coating. [ABSTRACT FROM AUTHOR]

Membrane fouling is a significant drawback in the implementation of membrane processes. To tackle this problem, the polyvinyl chloride (PVC) membrane was made by non-solvent induced phase separation (NIPS) and then placed on the 3D printed wavy support using a vacuum to prepare the patterned membrane. Characteristic tests were applied to study the properties of flat and wavy membranes. Fouling experiments were conducted using bovine serum albumin (BSA) solution, sodium alginate (SA) solution, and fruit-roll wastewater to evaluate the level of fouling in membranes. The total fouling ratio (TFR) for the flat membrane in the presence of BSA solution, SA solution, and fruit-roll wastewater was achieved 30%, 64%, and 53%, respectively. This ratio for the wavy membrane was 15%, 52%, and 36%, respectively. The solutions of sodium hypochlorite (NaOCl) and sodium dodecyl sulfate (SDS) were utilized for the chemical cleaning of membranes. NaOCl solution exhibited the highest cleaning efficiency at 94% for wavy membrane and 85% for flat membrane. [Display omitted] • The wavy support of the composite membrane was printed using a 3D printer. • The fouling behavior of PVC 3D printed composite membrane was assessed. • A 97% rejection for bovine serum albumin was achieved by both membranes. • Total fouling ratio was obtained significantly lower for the wavy membrane. • A higher cleaning efficiency was obtained for the wavy membrane. [ABSTRACT FROM AUTHOR]

The sugar production process, inherently water-intensive, is characterized by pronounced condensate formation during the evaporation and boiling phases. Given the environmental and resource implications, there is a scholarly emphasis on the potable reuse of such condensate by reverse osmosis (RO) in sugar mills. However, membrane fouling presents a significant challenge to the consistent operation of the RO process. This research examines the influence of operating parameters, namely transmembrane pressure and crossflow velocity, on the performance and fouling tendencies of an RO membrane during the purification of sugar mill condensate. The boundary flux theory was employed to model the permeate flux throughout this process. A boundary flux (5.92 L h−1m−2) and its corresponding operating pressure (10 bar) were determined. Moreover, a comparative analysis of the fouling mechanisms and the composition of the foulant layer under both sub-boundary and super-boundary conditions was undertaken. Under sub-boundary conditions, the fouling mechanism was identified as cake-intermediate blocking, while the super-boundary condition exhibited intermediate blocking. Under both conditions, organic fouling emerged as the primary fouling type. The TOC of surface contaminants ranged from 1.07 to 1.86 g/m2. Within this, proteins (484.0 to 850.3 mg m−2) and polysaccharides (201.5 to 379.2 mg m−2) were the dominant components. However, when operating conditions surpassed the boundary, there was a noticeable rise in inorganic fouling such as Ca (from 44.95 to 149.43 mg m−2) and Fe (from 4.40 to 112.09 mg m−2), which is likely due to the co-deposition of organic materials with inorganic ions. This research contributes to a more nuanced understanding of how operating conditions influence fouling mechanisms and provides foundational insights for addressing fouling challenges in sugar mill condensate purification. [Display omitted] • Analyzed the effects of operating parameters on purification and fouling. • A 5.92 L m−2 h−1 boundary flux value is suggested for effective RO fouling control. • Fouling under sub- and super-boundary conditions was comparatively studied. • Inorganic ions bridged with organic matter promoted the transition from sub-boundary to super-boundary conditions. [ABSTRACT FROM AUTHOR]

Calcium ion (Ca2+) is involved in the protein-mediated larval adhesion of fouling ascidians, yet the effects of environmental Ca2+ on larval adhesion remain largely unexplored. Here, the larvae of fouling ascidian C. robusta were exposed to different concentrations of Ca2+. Exposures to low-concentration (0 mM and 5 mM) and high-concentration (20 mM and 40 mM) Ca2+ significantly decreased the adhesion rate of larvae, which was primarily attributed to the decreases in adhesive structure length and curvature. Changes in the expressions of genes encoding adhesion-, microvilli-, muscle contraction-, and collagen-related proteins provided a molecular-level explanation for adhesion rate reduction. Additionally, larvae likely prioritized their energy towards immunomodulation in response to Ca2+ stresses, ultimately leading to adhesion reduction. These findings advance our understanding of the influencing mechanisms of environmental Ca2+ on larval adhesion, which are expected to provide references for the development of precise antifouling strategies against ascidians and other fouling species. [Display omitted] • Exposures to high- and low-concentrations of Ca2+ reduced larval adhesion rate. • Adhesive structure changes attributed to the reduction in adhesion rate. • Expression changes of adhesion-related genes explained adhesion reduction. • Collagen, microvilli, and muscle-related genes were related to adhesion reduction. • Larvae prioritized energy towards immunomodulation, leading to adhesion reduction. [ABSTRACT FROM AUTHOR]