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In this work, hydrophobic poly(vinylidene fluoride) membranes for potential membrane distillation applications, with pore sizes ranging from ~ 0.05 to ~ 0.30 μm, were prepared by employing triethyl phosphate (TEP) as a substitute to the hazardous, commonly used, toxic solvents. Membrane morphologies and properties were tailored based on the main parameters, such as the casting solution composition and the operational conditions, which affect the phase inversion process. Experimental results showed that exposure time to controlled humid air and temperature, as well as additive content in the dope solution, strongly influence the membrane formation. The use of TEP as an alternative solvent may contribute to the development of sustainable separation operations.

We report that diazepam binding inhibitor (DBI) is a glial messenger mediating crosstalk between satellite glial cells (SGCs) and sensory neurons in the dorsal root ganglion (DRG). DBI is highly expressed in SGCs of mice, rats, and humans, but not in sensory neurons or most other DRG-resident cells. Knockdown of DBI results in a robust mechanical hypersensitivity without major effects on other sensory modalities. In vivo overexpression of DBI in SGCs reduces sensitivity to mechanical stimulation and alleviates mechanical allodynia in neuropathic and inflammatory pain models. We further show that DBI acts as an unconventional agonist and positive allosteric modulator at the neuronal [GABA.sub.A] receptors, particularly strongly affecting those with a high-affinity benzodiazepine binding site. Such receptors are selectively expressed by a subpopulation of mechanosensitive DRG neurons, and these are also more enwrapped with DBI-expressing glia, as compared with other DRG neurons, suggesting a mechanism for a specific effect of DBI on mechanosensation. These findings identified a communication mechanism between peripheral neurons and SGCs. This communication modulates pain signaling and can be targeted therapeutically., Introduction Despite remarkable progress in our understanding of the fundamental biology of pain, current therapies for chronic pain are often inadequate and prone to serious side effects within the central [...]

This study explores the development of chitosan-based membranes blended with three distinct deep eutectic solvents (DESs) for the pervaporation separation of methanol and methyl tert-butyl ether. DESs were selected for their eco-friendly properties and their potential to enhance membrane performance. The chitosan (CS) membranes, both crosslinked and non-crosslinked, were characterized in terms of morphology, chemical composition, wettability, mechanical resistance, and solvent uptake. Pervaporation tests revealed that incorporating DESs significantly enhanced the membranes’ selective permeability toward methanol, with up to a threefold increase in separation efficiency compared to pristine CS membranes. The membranes demonstrated a strong dependence on feed temperature, with higher temperatures improving permeation flux but reducing separation factor. Crosslinking with glutaraldehyde further increased membrane selectivity by reducing free volume into the polymer matrix. These findings underscore the potential of DESs as green additives for improving the performance of biopolymer membranes, making them promising candidates for efficient and eco-friendly organic–organic separations.

During the production and laying phases of hot-mixing asphalt (HMA), various volatile organic compounds (VOCs) and noxious gases such as H2S are released into the atmosphere. These emissions are a serious environmental problem, a risk to human health, and expose workers and residents to unfriendly odours. The aim of this study was the development of a fast and sensitive analytical method to detect the H2S emitted from hot bituminous binder that is generally used in the various stages of asphalt production, processing, handling and during road construction. The method consisted in the analysis of evolved H2S from a flask with molten bitumen, using nitrogen as a carrier gas to lead the volatile compounds into a residual gas analyser equipped with a quadrupole mass spectrometer. The analysis was performed following the H2S-specific signals at m/z 33 (HS+) and at m/z 34 (H2S+) in real time, directly on the sample without laborious and expensive pre-treatments and with short response times (2S in nitrogen allows semi-quantitative H2S detection. The sensitivity and rapidity of the method were evaluated by quenching the release of sulphur compounds with commercial odour-suppressing agents. Upon addition of 0.1% of additive in two minutes, the H2S signal drops about 80% in two minutes, confirming the good response of the method, even with a very complex matrix.

Radioactive waste poses significant risks to human health and the environment due to the emission of gamma rays, beta particles, and alpha particles from natural or artificial radioactive elements. This paper reviews the essential sources of radioactive waste, their potential risks to humans and the environment, their classification depending on their chemical, physical, and radiological features, and the treatment techniques utilized to prevent them from leaking into the environment. In addition, the current study focuses on using membranes exclusively and membrane technologies in the remediation of radioactive liquid wastes. The use of pressure-driven membrane technologies, such as reverse osmosis, nanofiltration, ultrafiltration, and microfiltration, is particularly emphasized. Additionally, the use of nanomaterials like titanium dioxide, zinc oxide, silica, alumina, silver oxide, zeolite, copper ferrocyanides, and carbon nanotubes embedded with membranes to improve their effectiveness and enhance their applicability decreases the risks associated with radioactive contamination via modifying membrane properties including flow rate, the result of rejecting radioactive particles dissolved or suspended in contaminated water, hydrophobic and hydrophilic membrane's ability and among other properties. Moreover, incorporating nanoparticles into reinforced membranes enhances the mechanics of nanocomposite membrane surfaces via processes like adsorption and ion exchange with various radioactive ions. Besides increasing nanocomposite membranes' performance in reducing the hazardous radionuclides effects, it modifies membrane properties, such as enhancing antibacterial capabilities, antifouling, mechanical stability, and thermal stability. The article review also discusses hybrid pressure-driven membrane processes in disposing of radionuclides generated in nuclear power plants, hospitals, research facilities, and decontamination projects to protect human health and the environment.

The current work presented an in-depth investigation of the design and fabrication of thin film membranes for desalination applications by forward osmosis (FO). This includes manipulating the substrate membrane structure aiming to optimize the final thin film composite membrane characteristics. In this context, the MAX phase (Ti3AlC2) as a 2D material has been harnessed to impart novel desirable traits on the prepared membrane. MAX phase has been impregnated in two disparate concentrations and three different scenarios including the substrate membrane and the polyamide layer in both the aqueous and organic phases during the interfacial polymerization. Membranes were comprehensively characterized by a series of experimental tools and methodologies including Atomic Force Microscopy, Scanning Electron Microscopy, Contact Angle, Fourier-transform infrared spectroscopy, pore size and porosity. Results disclosed that substrate membrane structure has a pivotal impact on final TFC/TFN membrane performance. Besides, the MAX phase (Ti3AlC2) could significantly enhance the morphological characteristics of the membrane and ultimately the performance in terms of water flux and reverse salt flux based on the content and the way impregnated. The permeation properties of the composite membranes were significantly superior to the pure PES membrane and the mean pore size also increased with the addition amount of MAX phase (Ti3AlC2) increased.

We hypothesised that the protection against oxygen (PAO) of must and wine during vinification by avoiding contact with air can preserve the primary volatile organic compounds (VOCs) of Nerello Mascalese. PAO was performed in two seasons (2020 and 2021) using carbon dioxide pellets (CO2,s) and gas (CO2,g), inactivated yeasts and ascorbic acid during fermentation; the control wine was made via traditional vinification without adding the aforementioned components. During fermentation, the two winemaking processes mainly differed in terms of the application of aeration during maceration/fermentation in the pump-over and délestage activities, and the care taken to avoid contact with oxygen during racking. In both years, higher concentrations of polyphenols and total anthocyanins were found in the PAO wine (about 16 % and 20 % respectively). The concentrations of nerol, citronellol and geraniol were significantly higher in the PAO wine in both seasons, albeit with small differences which affected the sensory evaluation. The free/bound terpenes ratio was 0.35 (PAO) and 0.55 (Control). Bound C13-norisoprenoids contents were higher than the free ones; in the PAO wine, free 3-oxo-α-ionol and bound vomifoliol concentrations were slightly higher than in the control wine. Thiols were measured in Nerello for the first time. In 2020 in particular, sulfanylhexan-1-ol was present in larger amounts in the PAO wine. Applying PAO in the production of Nerello Mascalese modified certain VOCs, as well as the overall free/bound ratio due to the increase in bound VOCs, thus influencing the aroma of the wine.

The pervaporation process (PV) is one of the membrane separation methods. This process is characterized by low cost, ease of installation, no chemicals added, and work at medium temperatures. The pervaporation process is part of a chain of water treatment processes and has high efficiency in removing pollutants, drying processes, and others. The present review paper would be reviewed the related articles to show the efficiency of the separation of the solution by the pervaporation process by focusing on research that deals with the separation of volatile organic compounds (VOCs) from water such as benzene and toluene. Benzene compound was used to prepare some of the chemicals such as styrene, phenol, cyclohexane, aniline, and polyester resins. Also, it is used in the production of drugs, dyes, insecticides, and plastics, moreover, it is produced from the refineries' operations and mixes with the water used in these operations, where its concentration reaches up to 16 ppm. While toluene is a common solvent used for paints, glues, and printing ink. Toluene compound is produced from the refineries operations and mixes with the water used in these operations, where its concentration reaches up to 55 ppm, where these percentages for benzene and toluene are considered high and very dangerous to humans and the environment which causes many carcinogenic diseases. Also, researchers would be reviewing that worked on developing various types of membranes by adding different materials to improve membrane performance and increase the desired flux of components and separation factors with different working conditions.

One of the polymeric membranes' main limitations is their susceptibility to fouling, lowering the membrane's performance with time. Therefore, incorporating nanomaterials in polymer matrices has attracted great attention in wastewater treatment applications. It's a promising approach for enhancing membrane hydrophilicity and performance. Herein, ultrafiltration nanocomposite membranes were synthesized by applying the phase inversion method through immobilizing (0.1-0.4 wt.%) tungsten oxide (WO2.89) nanoparticles in a polyether sulfone (PES) matrix. Membrane's anti-fouling performance was evaluated against tinzaparin sodium. The data showed that the pure water flux improved with increasing nanoparticle loading, reaching its optimum value of 54.9 kg/m2 h at 0.4 wt.% WO2.89 nanoparticles compared to the neat membrane's 30.42 kg/m2 h. The results also demonstrated that the rejection efficiency and flux recovery ratio (FRR) against tinzaparin sodium was enhanced, by 44.89% and 12.69%, respectively, for the membranes modified with 0.4wt.% WO2.89 nanoparticles loading compared to the neat PES membrane. The data also showed that after exposing the nanocomposite membranes to UV light irradiation (λ=365 nm) and intensity (1200mW/cm2) for 1h, a further enhancement by 8.34% in FRR as compared to the membranes with the same percentage of nanoparticles loading without irradiation. It is concluded that the photocatalytic activity of WO2.89 nanoparticles in the decomposition of organic molecules on/close to the membrane surface was the impact that caused this improvement in membrane anti-fouling property

The present study highlights the influence of support and monomer properties on the performance of thin-film composite (TFC) membranes. For this purpose, a series of polyamide-cellulose acetate thin-film composite nanofiltration (TFC-NF) membranes were prepared by interfacial polymerization technique using cellulose acetate (CA) membrane as support and the monomer of cyclohexane-1,3,5 tricarbonylchloride (HTC) as an organic phase. The effect of the cellulose acetate concentration on the pore size of the membrane support was investigated using 15%, 16.5%, 18%, 19.5%, and 21.5% of cellulose acetate. m-phenylenediamine (MPD), piperazidine (PIP), and 1,3- cyclohexanebis (methylamine) (CHMA) were studied as monomers. Results displayed that PIP/HTC membrane is more hydrophilic and has more intense granular and convex structure with rougher surface compared to the other prepared membranes. The water flow and the porosity depended on the cellulose acetate concentration. The decrease in porosity complied well with permeability, contact angle, and SEM analysis. The membrane performances were evaluated for the retention of NaCl, CaCl2, and Na2SO4 retention. Comparing the Na2SO4 rejection with CaCl2 and NaCl, the former is higher than the latter.

Abstract In this work, Eucommia ulmoides leaf extract (EUOLstabilized silver nanoparticles (EUOL@AgNPs) incorporated sulfonated polyether sulfone (SPES)/polyethersulfone (PES) electrospun nanofiber membranes (SP ENMs) were prepared by electrospinning, and they were studied for the removal of lead (Pb(II)) and cadmium (Cd(II)) ions from aqueous solutions. The SP ENMs with various EUOL@AgNPs loadings were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscope, thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and contact angle (CA) measurements. The adsorption studies showed that the adsorption of Cd(II) and Pb(II) was rapid, achieved equilibrium within 40 min and 60 min, respectively and fitted with non-linear pseudo-second-order (PSO) kinetics model. For Cd(II) and Pb(II), the Freundlich model described the adsorption isotherm better than the Langmuir isotherm model. The maximum adsorption capacity for Cd(II) and Pb(II) was 625 and 370.37 mg g−1 respectively at neutral pH. Coexisting anions of fluoride, chloride, and nitrate had a negligible influence on Cd(II) removal than the Pb(II). On the other hand, the presence of silicate and phosphate considerably affected Cd(II) and Pb(II) adsorption. The recyclability, regeneration, and reusability of the fabricated EUOL@AgNPs-SP ENMs were studied and they retained their high adsorption capacity up to five cycles. The DFT measurements revealed that SP-5 ENMs exhibited the highest adsorption selectivity for Cd(II) and the measured binding energies for Cd(II), Pb(II), are 219.35 and 206.26 kcal mol−1, respectively. The developed ENM adsorbent may find application for the removal of heavy metals from water.

The low-fouling propensity of commercially available polyethersulfone (PES) membranes was studied after modification of the membrane surface via coating with polymerizable bicontinuous microemulsion (PBM) materials. The PBM coating was polymerized within 1 min using ultraviolet (UV) light exposure. It was detected on the PES membrane surface via attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. The PBM coating led to an average 10% increase in the hydrophilicity of the PES membrane surface and an increase in total organic content (TOC) removal by more than 15%. Flux-step tests were conducted with model foulant comprising 100 mg L−1 humic acid (HA) solution to detect the onset of critical fouling, characterized by a rapid and substantial increase in TMP, and to compare the fouling propensity of commercially available PES membranes with PBM-coated membranes. The critical flux was found to be about 40% higher for PBM spray-coated membrane and 20% lower for PBM casting-coated membrane than the commercial PES membrane. This demonstrates the performance advantages of the thin PBM layer spray-coated on PES membrane compared to the thick casting-coated PBM layer. The study showcases the potential of PBM spray-coated membranes over commercial PES membranes for use in membrane bioreactors (MBR) for wastewater treatment systems with reduced maintenance over longer operation periods.

Polymeric membranes are useful tools for water filtration processes, with their performance strongly dependent on the presence of hydrophilic dopants. In this study, polyaniline (PANI)-capped aluminosilicate (halloysite) nanotubes (HNTs) are dispersed into polyether sulfone (PES), with concentrations ranging from 0.5 to 1.5 wt%, to modify the properties of the PES membrane. Both undoped and HNT-doped PES membranes are investigated in terms of wettability (static and time-dependent contact angle), permeance, mechanical resistance, and morphology (using scanning electron microscopy (SEM)). The higher water permeance observed for the PES membranes incorporating PANI-capped HNTs is, finally, assessed and discussed vis-à-vis the real distribution of HNTs. Indeed, the imaging and characterization in terms of composition, spatial arrangement, and counting of HNTs embedded within the polymeric matrix are demonstrated using non-destructive Micro Particle Induced X-ray Emission (µ-PIXE) and Scanning Transmission Ion Microscopy (STIM) techniques. This approach not only exhibits the unique ability to detect/highlight the distribution of HNTs incorporated throughout the whole thickness of polymer membranes and provide volumetric morphological information consistent with SEM imaging, but also overcomes the limits of the most common analytical techniques exploiting electron probes. These aspects are comprehensively discussed in terms of practical analysis advantages.

Summary: Mechanical force is crucial in guiding axon outgrowth before and after synapse formation. This process is referred to as “stretch growth.” However, how neurons transduce mechanical input into signaling pathways remains poorly understood. Another open question is how stretch growth is coupled in time with the intercalated addition of new mass along the entire axon. Here, we demonstrate that active mechanical force generated by magnetic nano-pulling induces remodeling of the axonal cytoskeleton. Specifically, the increase in the axonal density of microtubules induced by nano-pulling leads to an accumulation of organelles and signaling vesicles, which, in turn, promotes local translation by increasing the probability of assembly of the “translation factories.” Modulation of axonal transport and local translation sustains enhanced axon outgrowth and synapse maturation.

During the production and laying phases of hot-mixing asphalt (HMA), various volatile organic compounds (VOCs) and noxious gases such as H2S are released into the atmosphere. These emissions are a serious environmental problem, a risk to human health, and expose workers and residents to unfriendly odours. The aim of this study was the development of a fast and sensitive analytical method to detect the H2S emitted from hot bituminous binder that is generally used in the various stages of asphalt production, processing, handling and during road construction. The method consisted in the analysis of evolved H2S from a flask with molten bitumen, using nitrogen as a carrier gas to lead the volatile compounds into a residual gas analyser equipped with a quadrupole mass spectrometer. The analysis was performed following the H2S-specific signals at m/z 33 (HS+) and at m/z 34 (H2S+) in real time, directly on the sample without laborious and expensive pre-treatments and with short response times (<6 s). Calibration with a standard mixture of 1000 ppm of H2S in nitrogen allows semi-quantitative H2S detection. The sensitivity and rapidity of the method were evaluated by quenching the release of sulphur compounds with commercial odour-suppressing agents. Upon addition of 0.1% of additive in two minutes, the H2S signal drops about 80% in two minutes, confirming the good response of the method, even with a very complex matrix. [ABSTRACT FROM AUTHOR]

Abstract Endowing anti‐fouling capabilities to water treatment membranes is a key feature for their long lifetime, but it continues to be a challenging task. Herein, a strategy for preparing composite membranes is reported comprising halloysite nanotubes (HNTs) as scaffolds to support a ruthenium substituted polyoxometalate (Ru4POM), with the goal of using evolved O2, resulting from the Ru4POM‐catalyzed H2O2 dismutation, as anti‐fouling agent. Two different amino alkyl derivatives, that is, a phosphonate and a silane, are grafted, respectively, in the lumen and on the surface of HNTs to support Ru4POM, and the resulting hybrid nanostructures are compared, in terms of catalytic efficiency and stability, to establish the most promising membrane additive. Porous polyether sulfone–based membranes are thus prepared to obtain a first proof of concept for this doping strategy. With respect to the former Ru4POM‐containing membranes, HNTs provide Earth‐abundant and low‐cost scaffolds for their efficient dispersion in the polymeric matrix. Preliminary tests on permeability and anti‐fouling behavior are finally discussed.