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Cellulose acetate (CA) membranes used in reverse osmosis (RO) desalination techniques often face fouling challenges. In this experimental study, the phase inversion method was employed to investigate the incorporation of graphene oxide nanoparticles (GONP) metal-organic frameworks (MOF), into the casting solution for composite CA-RO membranes. The effects of varying GONP concentrations on fouling resistance and hydrophilicity were evaluated using scanning electron microscopy (SEM), contact angle measurements, and water content analysis. The results demonstrated that the modified CA membrane with 0.05 wt% GONP exhibited improved water permeability (10.3 L/[m.sup.2] h) and salt rejection (95.8%) compared with the pristine CA membrane. These improvements stem from increased hydrophilicity and reduced fouling. This study's findings suggest that incorporating GONP into the polymeric doped solution can effectively mitigate fouling issues and enhance the performance of RO membranes in desalination applications. Highlights * GONP enhances hydrophilicity, reducing fouling in desalination. * Effects of varying GONP concentrations were studied. * GONP-CA membrane shows better permeability and salt rejection than pristine. * Nanocomposite membranes promise in overcoming fouling in RO membranes. KEYWORDS fouling resistance, graphene oxide nanoparticles, metal-organic frameworks, nanocomposite membranes, 1 | INTRODUCTION The physical properties of the membrane, such as its thickness and hydraulic permeability, as well as system factors such as transmembrane pressure, the length of the filtering [...]

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In this study, cellulose acetate (CA) membranes were prepared by the dry-wet phase inversion technique for desalination application. The effect of evaporation time on the properties of the prepared cellulose acetate membrane has been investigated. Different evaporation time was selected such as (30, 60, 90 and 120 s). The membrane characterization was carried out by using Fourier transform infrared (FTIR) analysis, scanning electron microscopy (SEM), contact angle measurements. Brackish water was used as a feed solution in a cross flow unit to evaluate the membrane performance. The effect of the evaporation time on the membrane's water flux and salt rejection was tested. The results showed that the different evaporation time has affected the structure as deduced by the FTIR analysis. The SEM analysis showed the asymmetric CA membranes structure, where a thin dense selective barrier layer was deposited (in a finger-like structure) on the surface of the prepared membranes. As the evaporation time increased, the thickness of this layer has increased and the value of the contact angle has decreased. The highest rejection, obtained from the membrane that was prepared with the evaporation time 60 s, reached 96.5% salt rejection with a relatively low flux of 1.0234 L/m² h. [ABSTRACT FROM AUTHOR]

This work aims to optimize the coagulation time for developing high-performance thin film composite polyamide reverse osmosis (TFC-PA-RO) membrane supported on nonwoven polyester fabric. A PA layer was synthesized by interfacial polymerization on the surface of polysulfone (PS) membrane. PS membrane was prepared by phase inversion technique. The effect of using two different types of nonwoven polyester fabric as support for the prepared membranes on their performance was investigated. The morphology of the prepared membranes was studied using scanning electron microscope. The performance (water flux and salt rejection) of the prepared RO membranes at different coagulation times (10, 30, 60, and 120 min) was compared with the standard RO membranes in 10 g L-1 NaCl solution. The TFC-PA-RO membrane supported on nonwoven polyester and prepared at a coagulation time of 30 min exhibited a maximum water flux of 47.6 L m-2 h-1 and salt rejection of 98% at 55 bar. On the other hand, the standard seawater high-rejection flat sheet membrane showed a maximum water flux of 27 L m-2 h-1 and salt rejection of 97.9%. [ABSTRACT FROM AUTHOR]

Relatedness between single nucleotide polymorphisms in IL8 and TLR4 genes and digital dermatitis resistance/susceptibility was investigated in seventy Holstein dairy cows. Animals were assigned into two groups, affected group (n = 35) and resistant group (n = 35) based on clinical signs and previous history of farm clinical records. Blood samples were collected for DNA extraction to ampliy fragments of 267-bp and 382-bp for IL8 and TLR4 genes, respectively. PCR-DNA sequencing revealed three SNPs in each of IL8 and TLR4 genes. The identified SNPs associated with digital dermatitis resistance were C94T, A220G, and T262A for IL8 and C118T for TLR4. However, the G349C and C355A SNPs in TLR4 gene were associated with digital dermatitis susceptibility. Chi-square analysis for comparison the distribution of all identified SNPs in both IL8 and TLR4 genes between resistant and affected animals showed no significant variation among the identified SNPs in IL8 gene. Meanwhile, there was a significant variation in case of TLR4 gene. As a pilot study, the present results revealed that identified SNPs in IL8 and TLR4 genes can be used as a genetic marker and predisposing factor for resistance/susceptibility to digital dermatitis in dairy cows. However, TLR4 gene may be a potential candidate for such disease. [ABSTRACT FROM PUBLISHER]