Forward osmosis membranes and processes: A comprehensive review of research trends and future outlook

Recently, Forward Osmosis (FO) desalination process has been widely investigated as a potential technology that could minimize the drawbacks of traditional desalination processes. To review the past, current, and future research scope of the FO desalination process, a statistical analysis that gives insights on the FO topics of interest is needed to assist researchers in the development of the FO technology. The main objective of this work is to conduct a survey highlighting the general and specific research trends in FO technology topics. The level of research interest is quantified based on the number of publications in each area collected from Science Direct and Scopus databases from 1999 to 2020. This survey indicated an increasing number of publications on the FO processes and membranes technology. The topics of interest are fouling phenomenon, draw solutions, membrane fabrication and modification. Some potential research areas highlighted in this review to help researchers to further advance the FO technology. This review reveals that recycling the draw solution and energy consumption are the most important research areas that have shown growth in the number of publications over the last eight years. An increase of publications was also found in the treatment of the organic matter over the last decade. To further promote FO process in industry, developing FO membranes, optimizing the energy consumption, and establishing an effective recovery system are the most essential topics. Thus, the interest in this process is expected to be continued in the future

Synthesis and Environmental Application of BiOI/BiOCl Composites

This work illustrates an enhanced visible light photocatalytic degradation of methyl orange dye (M.O.) by employing BiOI / BiOCl composites prepared under room temperature and without any organic precursors. Various experimental parameters have been studied, namely; composition of the composite, irradiation time and cell material. Composition D which implied 75% BiOI and 25% BiOCl has shown the highest bleaching of M.O. dye. This confirms the optimum photo-sensitization phenomenon for this composition in comparison to others. In the optimum photo-sensitized composite the electron of the conduction band reveals better reducing power and the hole of the valence band exhibits more oxidative power than those of pure BiOI electron and hole. Accordingly, under appropriate experimental conditions, methyl orange was significantly bleached using composite D

Solution of Nonlinear High Order Multi-Point Boundary Value Problems By Semi-Analytic Technique

In this paper, we present new algorithm for the solution of the nonlinear high order multi-point boundary value problem with suitable multi boundary conditions. The algorithm is based on the semi-analytic technique and the solutions are calculated in the form of a rapid convergent series. It is observed that the method gives more realistic series solution that converges very rapidly in physical problems. Illustrative examples are provided to demonstrate the efficiency and simplicity of the proposed method in solving this type of multi- point boundary value problems

Membrane electrode assembly with high efficiency and stability: effect of solvent type and membrane composition

Membrane electrode assembly (MEA) method is being widely considered in proton exchange membrane fuel cell (PEMFC) preparation. This work describes for the first time how PEMFC performance can be enhanced, while using relatively low temperature processing for the MEA, by choosing the suitable solvent and suitable ionomer (nafion) content. Three dispersion solvents (water, ethylene glycol and ethanol) have been examined here, and ethanol (with lowest boiling point) showed best PEMFC performance. In addition to its non-hazardous nature, the low boiling point ethanol allowed manufacturing the working membrane at 130°C or lower besides using a safe solvent to use. In each solvent system, different nafion concentrations were used (10%, 20% and 30%). The 30% nafion concentration in ethanol showed highest performance (Open circuit potential of 0.88 V and output working potential of 0.67 V at 20 mA/cm2 current density) among the series. The anode and cathode, of the MEA, were both fabricated using same catalyst material (Platinum) and same nafion sheet thickness (50 μm). The spray method was employed. The electrochemical performance for the prepared MEA fuel cells was assessed by linear sweep voltammetry to evaluate the open circuit voltage

Relation proximal point with some dynamical properties

In this paper we discussed relation proximal points with many of  dynamical properties through studied topological transformation group , and it will given  necessary condition for proximal relation to be minimal set ,and introduce  new define replete set and semi-replete set by using concept of the replete set and semi-replete set as well as  we introduce that many of  new  relations  and theorem. Key words: Proximal point, replete proximal point, syndetic set, semi-replete set, minimal set, almost periodic point             .

Interactions between nanoparticles in nanosuspension

Nanoparticles are particles with a characteristic dimension below 100 nm. The properties of nanoparticles differ substantially from those of “big” colloidal particles (size bigger than 1 m) because radius of surface forces, which is around 100 nm, is greater than or comparable with the nanoparticles size. The latter means that each nanoparticle could be completely covered by the surface forces of the neighbouring particles at small enough separation. It also means that the well-known Derjaguin approximation cannot be applied directly and some modifications are required. Pairwise interaction between nanoparticles can be used only at an extremely low volume fraction of nanoparticles (below some critical volume fraction, which is ~0.02%), and above this concentration a new theory based on many- particle interactions should be applied, which is yet to be developed. Some recent progress in the area of interaction between nanoparticles is reviewed and the properties of nanosuspensions based on interaction between nanoparticles are described. The authors have not attempted to cover all available literature in the area but instead have tried to underline the fundamental problems in the area which need to be addressed

A prospective comparative study of Lichtenstein procedure with and without mesh-fixation for inguinal hernia repair

Background: Repair of inguinal hernia is one of the most common elective operations performed in general surgery worldwide. Mesh-hernioplasty became the gold standard, because of its low recurrence rate in comparison with tissue repairs. The ideal repair must be simple, safe, easy to perform and require minimal dissection which provides enough space, should be cost effective with less hospital stay, less pain and less recurrence. The present study aimed at comparing the effect of mesh fixation and non-fixation in Lichtenstein technique for inguinal hernia repair.Methods: Hundred (100) patients with primary uncomplicated, unilateral inguinal hernia were treated between April 2019 and September 2020. Patients with inguinal hernia underwent Lichtenstein repair with mesh-fixation (group A) (n=50) and non-fixation (group B) (n=50). The mean operative time, post-operative pain score, average hospital study, post-operative complications and recurrence rates were compared between the two groups.Results: Mean operative time in non-fixation group- (group B) (32.24 min) was shorter as compared to fixation group-(Group A) (49.36 min) with a p value of 0.002. Post-operative pain score was lower in (group B) at 12 and 24 hours (3.71±1.409 and 2.2±0.8169) as compared to Group A at 12 and 24 hours (4.77±1.196 and 2.98±1.295) with a p value of <0.0001. The analgesia required in (group B) was less as compared to (group A). The post-operative complication and recurrence rates were almost identical in both the groups, with lesser incidence of groin pain and paresthesias in group B.Conclusions: In Lichtenstein inguinal hernia repair, non-fixation of mesh is safe and preferable option, with less operative time and less postoperative pain

Effect of membrane performance including fouling on cost optimization in brackish water desalination process

Membrane selection is a crucial step that will affect the economic feasibility of the membrane water treatment process. A comprehensive evaluation consisting of Verberne Cost Model, assessment of membrane performance and fouling propensity, osmotic pressure differential (OPD) and specific energy consumption (SEC) was employed to determine the potential of nanofiltration (NF 270, NF 90 and TS 80) and low pressure reverse osmosis (XLE) membranes to be used in brackish water desalination process. The aim was to save costs by replacing the typical brackish water reverse osmosis (BW 30) membrane. Verberne Cost Model showed that higher flux NF membranes resulted in lower overall costs. However, after assessing the membrane performance, NF 270 and TS 80 were excluded due to their high fouling propensity and their failure to reduce total dissolved solids (TDS) in the solution. Instead, NF 90 membrane which produced water with acceptable TDS and has moderate permeability ended up to be more cost competitive compared to BW 30 membrane, with 17%-21% lower total costs and 13%-17% lower water costs. Apart from this, OPD and SEC were applied to justify the selection of optimal membrane recovery rate based on the water costs calculated. It was determined that the optimal recovery rate was 80% where the SEC and water costs were close to available water treatment plants. Overall, this study showed that the selection of membrane can be carried out by using Verberne Cost Model assisted by assessment of membrane performance and fouling propensity, OPD and SEC