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The shortage of clean water sources and increase of demand for fresh water have become as major global challenges not only in industries but also inhuman life. Meanwhile, membrane technology has been extensively noticed due to high separation efficiency, energy-saving and environmentally-friendly characteristic. So, development of new membrane is a vital step in advancing of membrane application in water-treatment. This paper presents a comprehensive review on development of high-performance nanofiltration membrane based on nanotechnology for wastewater treatment. Application of new nanomaterials has enabled fabrication of NF-membranes with improved separation properties for pollutants removal from water. Recognizing that conventional membranes are not necessarily suitable for industrial applications and/or process intensifications many attempts were made recently to use of nanomaterials into NF-membranes, aiming to overcome trade-off relationship between flux/selectivity and to improve their stability. So, development of new structured nanomaterial with desirable properties is one of most crucial research topics for membrane researchers. Accordingly, an overview on different methods to design of advanced nanomaterial presented that allow us to overcome their inherent problems in membranes fabrication such as agglomeration, defects formation, insufficient pores’ tuning, poor active sites and anti-fouling properties; however, selection of appropriate nanomaterials is a challenge of utmost difficulty. Various types of nanomaterials such as zeolites, carbon based, framework (MOF/ZIF/COF), nano-biopolymers and special nanoparticles such as SFNPs, SFNCs, POSS, ZCPs, and nickel hydroxide nanosheet are presented and their roles in NF-transport are discussed as well as strategies for surface modification of nanoparticles to promoting their surface charges density. Moreover, fabrication methods of nano enhanced NF-membranes including layer by layer assembly, hollow fiber spinning, electrospinning of nanofibers, construction of thin-film nanocomposite besides blending, co-polymerization; cross-linking and grafting techniques are discussed. A proper view for selection of appropriate nanoparticles in membrane fabrication is offered while considering types of pollutants to be removed.

In this study, a mixed matrix polyethersulfone-based nanofiltration membrane was prepared by incorporation of (cobalt ferrite/activated carbon) composite nanoparticles. The composite nanoparticles were also synthesized using the chemical precipitation technique. The FTIR, XRD and FESEM were used to characterize the synthesized nanoparticles. The fabricated membranes were also studied using SEM, 3D surface image, and water contact angle, mean pore size and porosity measurements. The water flux, salt rejection and antifouling ability of membranes were investigated. The blended membranes showed a more hydrophilic and smoother surface compared to the pristine membrane. The membrane PWF was declined initially using 0.05 wt. % (CoFe2O4/AC) nanoparticles into membrane body and then enhanced by a further increase of nanoparticles’ concentration up to 0.1 wt. % in membrane matrix; PWF was reduced again for the blended membranes at higher concentration of nanoparticles. The NaCl and Na2SO4 rejections were enhanced from (42% to 85%) and (55% to 95%) by the use of (CoFe2O4/AC) nanoparticles into the membrane body. The blended membranes also exhibited appropriate anti-fouling property and more stable flux compared to the pristine membrane. The highest Pb2+, Ni2+, and Cu2+ rejections were found 86%, 90%, and 97%, respectively, for the blended membrane containing of 1 wt. % (CoFe2O4/AC) compared to others.

Smart microgrids are experiencing an increasing growth due to their economic, social, and environmental benefits. However, the inherent intermittency of renewable energy sources (RESs) and users’ behavior lead to significant uncertainty, which implies important challenges on the system design. Facing this issue, this article proposes a novel robust framework for the day-ahead energy scheduling of a residential microgrid comprising interconnected smart users, each owning individual RESs, noncontrollable loads (NCLs), energy- and comfort-based CLs, and individual plug-in electric vehicles (PEVs). Moreover, users share a number of RESs and an energy storage system (ESS). We assume that the microgrid can buy/sell energy from/to the grid subject to quadratic/linear dynamic pricing functions. The objective of scheduling is minimizing the expected energy cost while satisfying device/comfort/contractual constraints, including feasibility constraints on energy transfer between users and the grid under RES generation and users’ demand uncertainties. To this aim, first, we formulate a min–max robust problem to obtain the optimal CLs scheduling and charging/discharging strategies of the ESS and PEVs. Then, based on the duality theory for multi-objective optimization, we transform the min–max problem into a mixed-integer quadratic programming problem to solve the equivalent robust counterpart of the scheduling problem effectively. We deal with the conservativeness of the proposed approach for different scenarios and quantify the effects of the budget of uncertainty on the cost saving, the peak-to-average ratio, and the constraints’ violation rate. We validate the effectiveness of the method on a simulated case study and we compare the results with a related robust approach. Note to Practitioners —This article is motivated by the emerging need for intelligent demand-side management (DSM) approaches in smart microgrids in the presence of both power generation and demand uncertainties. The proposed robust energy scheduling strategy allows the decision maker (i.e., the energy manager of the microgrid) to make a satisfactory tradeoff between the users’ payment and constraints’ violation rate considering the energy cost saving, the system technical limitations and the users’ comfort by adjusting the values of the budget of uncertainty. The proposed framework is generic and flexible as it can be applied to different structures of microgrids considering various types of uncertainties in energy generation or demand.

Surface modification of thin-film nanofiltration membranes was carried out to produce high water permeable NF membranes by Air-Ar plasma treatment. The effect of composition of used gases on membrane properties was investigated. Results showed that the plasma treatment decreased the water contact angle obviously from 80.4° to 6.5°, which in turn would increase the membrane surface hydrophilicity. The results of FTIR spectra decisively confirmed the formation of hydrophilic nitrogen and oxygen compounds on the membrane surface. The SEM images of membrane surface also showed significant changes after plasma treatment. AFM analysis indicated smoother surface for the modified membranes compared to pristine membrane; the roughness declined from 55.85 nm for virgin membrane to 28.33 nm for modified membranes. The salt rejection was 90% for pristine membrane and 76.35% to 92.45% for the plasma treated membranes. The water flux for modified membrane treated by 50% Air-50% Ar plasma increased ∼1,446.1% compared to the virgin membrane, whereas the selectivity declined only ∼15.1%.

8-Hydroxyquinoline (8-HQ) was used for modification of Fe3O4 nanoparticles (NPs) and preparation of polyethersulfone (PES)-based mixed matrix membranes (MMMs) by phase inversion process. The synthesized nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR), Energy dispersive x-ray spectroscopy (EDX), and Field emission scanning electron microscopy (FESEM). The effect of different concentrations of 8-HQ/Fe3O4 NPs into the PES as membrane matrix was investigated by FESEM and atomic force microscopy (AFM). The performance of prepared membranes was evaluated by the water contact angle, pure water flux (PWF), porosity, means pore size, and salt rejection. Bovine serum albumin (BSA) solution was used to investigate the antifouling properties of fabricated membranes. The results showed a decreasing water contact angle from 68.1° for the pristine membrane to 38.3° for M5 at 0.5 wt% 8-HQ/Fe3O4 NPs. The PWF enhanced for all mixed matrix membranes compared with the pristine membrane. The highest PWF (21.5L/m2h) was measured for M4 at 0.2wt% NPs, Wwhile it was 7.1 L/m2h for pristine membrane. Salt rejection improved from 58.55% in M1 (pristine membrane) to 96% in M4 (at 0.2 wt% of 8-HQ/Fe3O4 NPs). Also, the modified membranes showed suitable antifouling property.

The problem of frequent itemset mining is one of the more important problems in data mining which has been extensively employed across a wide range of other relevant tasks such as market basket analysis in marketing, or text analysis in text mining applications. The majority of the deterministic frequent itemset mining algorithms which have been proposed in recent years use some sort or another of an optimal data structures to reduce the overall execution time of the algorithm. In this paper, however, we have tried instead to introduce an approximation algorithm which works by converting the problem into a clustering problem where similar transactions are grouped together. Each cluster centroid represents an itemset which may be assumed to be a candidate frequent itemsets. The validity of this assumption is simply verified by calculating the support count of these itemsets. Those who meet the min-support condition are considered to be an actual frequent itemset. As for the remaining itemsets, they are then passed to MAFIA which extract all maximal frequent itemsets therefrom. Experimentations made on several well-known and diverse datasets show that the proposed algorithm performs almost always faster, and in some cases up to 10 times faster, than the existing deterministic algorithms, and all this by retaining up to 95% of its accuracy.

Poly (ethylene-oxide) (PEO)-based membranes have attracted much attention recently for CO2 separation because CO2 is highly soluble into PEO and shows high selectivity over other gases such as CH4 and N2. Unfortunately, those membranes are not strong enough mechanically and highly crystalline, which hinders their broader applications for separation membranes. In this review discussions are made, as much in detail as possible, on the strategies to improve gas separation performance of PEO-based membranes. Some of techniques such as synthesis of graft copolymers that contain PEO, cross-linking of polymers and blending with long chains polymers contributed significantly to improvement of membrane. Incorporation of ionic liquids/nanoparticles has also been found effective. However, surface modification of nanoparticles has been done chemically or physically to enhance their compatibility with polymer matrix. As a result of all such efforts, an excellent performance, i.e., CO2 permeability up to 200 Barrer, CO2/N2 selectivity up to 200 and CO2/CH4 selectivity up to 70, could be achieved. Another method is to introduce functional groups into PEO-based polymers which boosted CO2 permeability up to 200 Barrer with CO2/CH4 selectivity between 40 and 50. The CO2 permeability of PEO-based membranes increases, without much change in selectivity, when the length of ethylene oxide is increased.

L-cysteine as an amino acid was used for the modification of glycidyl POSS in the synthesis of L-cysteine functionalized POSS, including carboxyl, hydroxyl, and diamine groups. Then, the synthesized nanoparticles were applied to fabrication of L-cysteine POSS-TiO2 composite nanoparticles. NF membranes were prepared from the incorporation of different concentrations of the synthesized composite nanoparticles into the polyether-imide (PEI) as the membrane matrix. The prepared membranes were characterized by Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FESEM) and atomic force microscope (AFM). Moreover, the separation performance of the NF membranes was examined by pure water flux (PWF) and the separation of Na2SO4, Pb(NO3)2, Cr(NO3)2 and Cu(NO3)2 aqueous solutions. The results showed the increase of pure water flux due to present hydrophilic groups on the membrane surface. The highest pure water flux obtained was 22.03 L/m2h in 1 wt% of nanoparticles. Furthermore, the rejection of Na2SO4 and Pb(NO3)2, CrSO4, and Cu(NO3)2 improved to 78%, 64%, 67% and 66% that increased 11%, 33%, and 22%, and 39% compared with the pristine PEI membrane, respectively. Finally, the best FRR% (81%) was obtained for 0.1 wt% of the composite nanoparticles (M3).

CuO/PES composite membranes were fabricated through phase inversion method, focusing on fouling reduction and improving separation performance. Copper oxide nanoparticles were used as filler additive in the membrane structure. The effect of the embedded CuO nanoparticles on the morphology was studied by considering SEM, SOM and 3D surface images. Flux recovery ratio (FRR%), water contact angle, water content, mechanical tensile strength, porosity and mean pore size, salt rejection and water flux were investigated to evaluate the performance of fabricated membranes. The SOM images showed a uniform surface for the modified membranes. SEM images showed a finger-like structure for the modified membranes. Results also denoted an increment in porosity and mean pore size of membrane at low concentration of CuO NPs, whereas the opposite trend was found at higher concentration of nanoparticles. Utilizing CuO NPs enhanced the membrane tensile strength obviously PWF significantly was improved by applying CuO NPs in membrane matrix. Highest PWF (42.63 L/m2h) was observed for PES-0.05wt% CuO blended membrane, whereas it was 10.41 (L/ m2h) for pristine ones. Salt rejection also measured 82% for virgin membrane and 63-90% for modified membranes. Moreover, FRR% were measured (~77% to ~93%), while the pristine membrane showed ~63% FRR%.

Surface functionalization of zinc oxide (ZnO) nanoparticles was performed by glycidyl POSS. The synthesized nanoparticles were applied to prepare polyether-imide based-nanofiltration membranes by phase inversion method. The characterizations were done by FESEM, EDX and AFM analysis. The effect of different concentrations of POSS-ZnO (PZ) nanoparticles was investigated to evaluate the separation performance of prepared membranes by contact angle measurement, pure water flux (PWF), rejection of aqueous solutions including Na2SO4, Pb(NO3)2, Cu(NO3)2 and flux recovery ratio (FRR%). The prepared PEI/PZ membranes showed significant separation performance and antifouling properties compared with neat PEI and PEI/ZnO membranes. The highest pure water flux (42.4 L/m2h) was revealed for M1-PZ in 0.001 wt% of PZ nanoparticles, whereas that was 17 (L/m2h) for neat membrane and 12–18 (L/m2h) for PEI/ZnO, respectively. Also, salt rejection was low for blended PEI/ZnO membranes. By incorporation of PZ into the PEI, Na2SO4, and Pb (NO3)2 rejection improved to 83% and 59%, respectively. Moreover, the M3-PZ showed the best separation performance for Cu (NO3)2 with the rejection of 67%. The highest antifouling properties were obtained for M4-PZ with FRR% of 59%, which is significant compared with 15% for PEI/ZnO and 30% for neat PEI membranes.

The current study focuses on the electrochemical, morphological and antibacterial characteristics of a new type of polyvinylchloride based cation exchange membrane modified by BaFe12O19/CuO composite nanoparticles. The used BaFe12O19/CuO composite nanoparticles were synthesized by chemical precipitation technique. The formation of BaFe12O19/CuO was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). SEM and scanning optical microscopy (SOM) images also showed relatively uniform structure for the prepared membranes. The membrane water uptake was enhanced up to 14.5% in presence of BaFe12O19/CuO composite nanoparticles. The membrane ion exchange capacity, membrane potential, transport number, surface charge density, permselectivity and ion permeability/flux were also improved sharply by increase of additive concentration up to 2 wt% and then showed decreasing trend by more BaFe12O19/CuO content ratio from 2 to 8 wt%. The membrane areal electrical resistance were decreased significantly from ∼24 to ∼5 (Ω cm2) by using of BaFe12O19/CuO nanoparticles. Moreover, modified membranes demonstrated good ability to removal of E-coli bacteria. Keywords: Cation exchange membrane, BaFe12O19/CuO nanoparticles, Chemical precipitation, Electrochemical properties, Antibacterial characteristic

Increasing environmental awareness accompanied by the recent fluctuations in the fossil fuels underline the need to focus more on the management of energy mix and turn the attention towards renewable energies (REs). Diffusion and commercialization of renewable energy technologies are of paramount importance, particularly for developing countries. However, there are serious challenges and barriers that can be discussed in different aspects. This paper presents an applied and novel framework to tackle the challenges of diffusing and commercializing biomass energy technologies (BET) in developing countries. As a good example, our study focuses on the commercialization of the BETs in Iran. For this purpose, we provide an overview of the importance of commercialization of BETs. Then, by analysis of the literature and best cases, we identify crucial elements for commercialization of the BETs. Conducted surveys and theme analysis have resulted in a framework with 8 major dimensions and a total of 73 diverse components. The dimensions are technical and infrastructural; R & D and technology transfer; investment; social, cultural and behavioral; promotion and distribution; marketing and market building; macroeconomics; and support policy. Findings suggest that ‘investment' and ‘technical and infrastructural' dimensions are the two major pillars of the framework for commercialization of the BETs for developing countries.

In this study, nanocomposite polyvinyl chloride-based heterogeneous cation exchange membranes were fabricated by embedding graphite nanoparticles through solution casting technique. The effects of graphite nanoparticle concentrations in the membrane body on the electrochemical properties of blended membranes were investigated. FESEM and SOM images showed uniform distribution of particles and a uniform surface for the fabricated membranes. XRD patterns showed that the crystallinity of membrane enhanced by the increase of graphite nanoparticle dosage. The obtained results imply that increasing the concentration of graphite nanoparticles in the modified membranes has produced a rougher and a more hydrophobic surface. Membrane potential, transport number, selectivity, flux, and water content for the blended membranes were enhanced initially by increase of graphite nanoparticle concentration up to 2 wt% and after that downward trend found. The electrical resistance of the membranes was reduced by the use of graphite nanoparticles obviously.

Iran has become one of the most CO2 emitting countries during the last decades. The country ranks after Japan and Germany in terms of CO2 emissions. However, from an economic viewpoint, the gross domestic product (GDP) of Iran is lower than the summation of Berlin and Tokyo GDP. Moreover, a large proportion of Iran’s revenue comes from the crude oil export; therefore, this level of CO2 emission cannot be economically driven and is as a result of high energy intensity in this country. This is while the government also has not a clear program in this regard. The Sixth Five-year Development Plan of Iran, in addition, sets a number of ambitious targets mostly regarding the energy intensity, GDP growth, and renewable energies, but does not mention to CO2 emission issue. Therefore, prospects for an early settlement of the dispute are seemingly dim. Our aim is to predict Iran’s CO2 emissions in 2030 under assumptions of two scenarios, i.e. business as usual (BAU) and the Sixth Development Plan (SDP), using multiple linear regression (MLR) and multiple polynomial regression (MPR) analysis. Findings suggest that Iran most likely will not meet its commitment to the Paris Agreement under the BAU’s assumptions; however, full implementation of the ambitiously shaped SDP could have met the target by end 2018.

In this study, mixed matrix polyethersulfone based nanofiltration membranes were prepared by composite CoFe2O4/CuO nanoparticles. The CoFe2O4/CuO nanoparticles were synthesized by a chemical precipitation technique, and then characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Then, the effect of embedded CoFe2O4/CuO nanoparticles into PES based NF membrane on its physico/chemical properties, separation performance and antifouling ability was studied. The atomic force microscopy (AFM), scanning electron microscopy (SEM), water contact angle, pure water flux, salt rejection, antifouling ability, as well as heavy metal ions separation were used in membrane characterization. The blended membranes with CoFe2O4/CuO exhibited higher surface hydrophilicity and smoother surface than the bare membrane. The water contact angle and average surface roughness reduced from (70° to 35°) and (45 nm to 24 nm) for the bare PES membrane and blended [PES-0.5 wt% CoFe2O4/CuO] membrane, respectively. The PWF measured 34.5 (L/m2 h) for the blended [PES-0.5 wt% CoFe2O4/CuO] membrane and 12 (L/m2 h) for the bare ones. The NaCl and Na2SO4 rejection were increased from (32% to 72%) and (62% to 95%) by introducing CoFe2O4/CuO into the PES matrix. The FRR measured ∼42% for bare membrane whereas that was ∼90% for the superior blended membrane with 0.5 wt% CoFe2O4/CuO nanoparticles. The Cu2+, Ni2+ and Pb2+ rejection measured 98%, 92% and 88% for the blended [PES-0.5 wt% CoFe2O4/CuO] membrane whereas they were 85%, 80% and 78% for the pristine PES membrane. The reusability study for the superior blended membrane showed a slight decrease in average performance less than 4.9%.

The current study aimed to investigate the impacts of different concentrations of GO/PANI nanocomposites (25, 50 and 100 mg L−1), in comparison with GO and PANI, on seed germination behaviors, morpho-physiological and biochemical traits in intact (mucilaginous) and demucilaged seeds, and young seedlings of the medicinal plant Salvia mirzayanii. Upon exposure to GO, seed germination was delayed and reduced, and growth attributes (root and shoot length, shoot fresh weight, and total chlorophyll content) declined, all of which could be attributed to the reductions in water uptake and oxidative stress particularly in demucilaged seeds. A hormetic dose-dependent response was observed for the growth traits in both intact and demucilaged seedlings upon exposure to GO/PANI concentrations, i.e. low-concentration stimulation and high-concentration repression. Elevated levels of H2O2 in shoot tissue of the seedlings exposed to GO and high concentration of GO/PANI, in comparison with those exposed to low levels of GO/PANI and control, were linked with the activities of the antioxidant enzymes SOD, CAT, POD, and total phenolics. Overall, the results showed high toxicity of GO on germination and early growth of S. mirzayani that was more evident in demucilaged seedlings, whereas GO/PANI stimulated germination, and the effects on seedling growth were stimulatory or inhibitory depending on the application dose and presence of mucilage. Furthermore, the capacity of GO/PANI nanocomposites to improve germination and cause a regular porosity pattern in roots accompanied by improved water uptake and early establishment of S. mirzayanii propose potential implications of GO/PANI nanocomposites for seeds/plants in drought-prone ecosystems.

This research focuses on the formation of ionic clusters and the transport properties of metal ions through electrodialysis heterogeneous cation exchange membrane modified by l-cysteine as a polar additive. The molecular electrostatic potential of l-Cyst and resin particle showed appropriate reactive sites for electrophilic and nucleophilic attacks. Furthermore, the calculated interaction energy confirmed the presence of strong interactions between the l-Cyst molecule and the resin particle. Elemental mapping, scanning electron microscopy (SEM), and scanning optical microscopy (SOM) images of the blended membranes represented a relatively uniform surface and particle distribution. Membrane water uptake and surface hydrophilicity were enhanced in the presence of l-Cyst. The blended membranes demonstrated high selectivity (> 99%), lower electrical resistance (

This study investigates the efficacy of Fe3O4/PVP composite nanoparticles incorporating into heterogeneous cation exchange membranes on their physicochemical properties and desalination performance via electrodialysis. The blended membranes were fabricated through solution casting technique and characterized by scanning optical microscopy (SOM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and energy-dispersive X-ray spectroscopy (EDX). The areal electrical resistance declined sharply from 14.7 (Ω cm2) for the pristine membrane to 5.8 (Ω cm2) for the Fe3O4/PVP embedded mixed matrix membranes, whereas the change in membrane water uptake was less that 4%. The blended membranes showed smoother and more hydrophilic surface compared to pristine membrane. The membrane potential, transport number, and permselectivity were also improved obviously by utilizing of Fe3O4/PVP nanoparticles. The nanocomposite membranes demonstrated good potential in separation of bi- to mono-valent ions (Ba2+/Na2+) which was ~ 2.1.

A new type of magnetic mixed matrix cation exchange membrane was prepared by incorporating cobalt ferrite nanoparticles for chromium ions removal via electrodialysis. The CoFe2O4 nanoparticles were synthesized via a simple chemical precipitation method. The synthesized nanoparticles and mixed matrix lab-made membranes were characterized by XRD, FT-IR, EDX, SEM and SOM. The images showed a uniform particle distribution and a relatively uniform surface for the prepared membranes. Utilizing CoFe2O4 nanoparticles in the membrane matrix led to increase of the membrane electrical conductivity and surface hyrophilicity. The membrane potential, charge density, permselectivity, transport number, ion exchange capacity and water content in the membrane were enhanced by using CoFe2O4 nanoparticles loading ratios up to 2 wt% and then decreased again for concentrations above 2 wt%. The sodium flux was also increased sharply by using cobalt ferrite nanoparticles in the membrane matrix. The magnetic PVC-CoFe2O4 membrane showed more dialytic rate in chromium ions removal compared to pristine PVC membrane which could be linked to strong affinity of magnetic nanoparticles in heavy metal ions adsorption.

This is the first study that presents a supply chain (SC) resilience measure with the ripple effect considerations including both disruption and recovery stages. SCs have become more prone to disruptions due to their complexity and strategic outsourcing. While development of resilient SC designs is desirable and indeed critical to withstand the disruptions, exploiting the resilience capabilities to achieve the target performance outcomes through effective recovery is becoming increasingly important. More adversely, resilience assessment in multi-stage SCs is particularly challenged by consideration of disruption propagation and its associated impact known as the ripple effect. We theorize a new measure to quantify the resilience of the original equipment manufacturer (OEM) with a multi-stage assessment of suppliers’ proneness to disruptions and the SC exposure to the ripple effect. We examine and test the developed notion of SC resilience as a function of supplier vulnerability and recoverability using a Bayesian network and considering disruption propagation using a real-life case-study in car manufacturing. The findings suggest that our model can be of value for OEMs to identify the resilience level of their most important suppliers based on forming a quadrant plot in terms of supplier importance and resilience. Our approach can be used by managers to identify the disruption profiles in the supply base and associated SC performance degradation due to the ripple effect. Our method explicitly allows to uncover latent, high-risk suppliers to develop recommendations to control the ripple effect. Utilizing the outcomes of this research can support the design of resilient supply networks with a large number of suppliers: critical suppliers with low resilience can be identified and developed.

A heterogeneous anion exchange membrane was modified by introducing polyaniline nanoparticles, in order to enhance its electrochemical properties in view of chloride and sulfate ion removal from water. Polyaniline nanoparticles were synthesized by facile chemical polymerization technique. Nanoparticles were characterized by FTIR, FESEM, and XRD. In addition, SOM images showed a uniform surface for membranes. Utilizing PANI nanoparticles in membrane body led to increase of water content, ion exchange capacity, surface hydrophilicity, and electrical conductivity. Membrane transport number and permselectivity were improved in NaCl solution by incorporating PANI nanoparticles; in Na2SO4 solution, they showed an opposite trend. The chloride and sulfate flux were enhanced by a low PANI concentration and declined at higher concentration. Modified PANI membranes showed a lower selectivity and flux for bivalent ions compared to monovalent ions. Membrane mechanical resistance was increased by using PANI in concentrations up to 2 wt% and decreased at higher PANI ratios.

Resilient supplier selection is a key strategic decision in the context of the supply chain (SC) disruption management. We offer an efficient solution to the resilient supplier selection and optimal order allocation problem. We first show how to compute the likelihood of disruption scenarios for the supplier selection problem using a probabilistic graphical model. That model can capture (i) a large number of disruptive events with no computational burden, and (ii) the dependencies among disruptive events and their impacts on supplier performance, i.e., the ripple effect. We then propose a stochastic bi-objective mixed integer programming model to support the decision-making in how and when to use both proactive and reactive strategies in supplier selection and order allocation. The outcomes of this research, if utilized properly, can benefit suppliers to find the optimal set of operational decisions (e.g., the optimal level of surplus capacity and restorative capacity) that enhance their resilience capabilities. Finally, the proposed model can be utilized as a decision support tool to assist manufacturers in performance assessment of supplier alternatives when costs and resilience are considered simultaneously, which helps to build up both efficient and resilient SC (i.e., to achieve the SC resilience) to ensure the operations continuity. These outcomes can help SC managers organize their disruption risk mitigation efforts with balancing the efficiency and resilience while focusing on critical suppliers and order (re)-allocation that will have a more significant impact on the performance of the SC when disrupted.

This paper is devoted to a compact and ultra-wideband (UWB) CPW (Co-Planar Waveguide)-fed square slot Antenna for wearable applications. In our design, the antenna fabricated on the cotton layer with dielectric constant of 1.65 with compact size of 0.76λ × 0.72λ in which the antenna has a silver based fabric radiating element. The UWB operation of this compact antenna varies from 3.2 GHz to 16.3 GHz considering the fractional band width (FWB) to be 135. To clarify for wearable applications, this compact antenna were compared with different dielectric constant such as non-woven (er = 1.15, thickness (h) = 5 mm) and FR4 (er = 4.4, h = 1.6 mm). This antenna, then, were examined both in air, and on a suit shirt situations. The Antenna which is located on body compared to antenna in air has a lower efficiency. Furthermore; it decreases the radiation toward body approximately 10 dB. It also causes frequency shifts and reduces the bandwidth. In both cases, the examinations indicated the compact antenna in the UWB is very desirable.

In this study, the physico-chemical properties, separation performance and antifouling ability of mixed matrix PES-based nanofiltration membranes decorated by (Fe3O4–polyvinylpyrrolidone) composite nanoparticles were investigated. The morphology of resulted membranes was characterized by scanning electron microscopy)SEM), scanning optical microscopy (SOM) and 3D surface images. The effect of incorporated nanoparticles on membrane properties and performance was determined using water contact angle, water content, membrane pore size and porosity, tensile strength, water flux, salt rejection and BSA solution filtration. The membrane water content was enhanced slightly by embedding Fe3O4/PVP up to 0.1 wt.% in membrane body and then reduced again by more NPs ratio. The water contact angle also decreased from 65.18° for neat membrane to 50.5° for the modified ones. All mixed matrix membranes showed higher water flux compared to pristine membrane that measured 3.14 (L/m2 h) for bare membrane and 9.96 (L/m2 h) for the superior ones. Salt rejection measured 82% for the pristine membrane whereas that was between 77%–90% for the nanocomposite membranes. Membrane tensile strength also improved by increase of composite NPs ratio into the polymer matrix. The nanocomposite membranes showed more BSA solution flux and outstanding antifouling properties compared to bare ones. The FRR measured ∼ 46.2% for bare membrane whereas that was ( ∼ 69.9% to ∼ 89.5%) for the nanocomposite membranes.

Electrodialysis cation exchange membranes were modified by incorporating [graphene oxide (GO)-co-Ag] composite nanoplates. The [GO-co-Ag] composite nanoplates were prepared by magnetron sputtering technique assisted with plasma treatment. XRD pattern and SEM image confirmed [GO-co-Ag] formation decisively. SEM, EDX, and SOM images showed relatively uniform surface for prepared membranes. Use of [GO-co-Ag] caused to formation of a compact structure for the blended membranes. The cross-sectional SEM images exhibited a specific direction for [GO-co-Ag], which at nanoscale position. The membrane surface wettability was improved by incorporating of [GO-co-Ag]. Membrane water content, transport number, and permselectivity were enhanced initially by utilizing of [GO-co-Ag] up to 0.5 wt% and then decreased by more concentration. Flux and E-conductivity enhanced sharply by using of [GO-co-Ag]. Use of [GO-co-Ag] into membrane matrix also caused to enhancement of mechanical resistance whereas declines the chemical oxidative stability. Results showed good antibacterial ability for blended membranes in E. coli removal.

Regarding the role of time in human life, the driving time can be a tangible criterion to represent the quality of flow in every traffic facility such as freeway interchanges. There are a lot of appreciable attempts which focused on determining travel time in long-length paths in the networks. But, there are not enough considerable studies on predicting the driving time in short-length paths such as the parts of an interchange. Besides, when the study area has to be changed, or when the purpose is to design a nonexistent interchange, predicting the driving time in diverse parts of an interchange cannot be carried out by direct measurement, and when there is information shortage on some hardly achievable traffic-based characteristics of interchanges, predicting the driving time by common procedures will be so hard or even impossible. Using simulation software usually needs considerable time and budget, too. In this paper, focus was on studying the short-length fragments of freeway interchanges to predict driving time by investigating ten real-world interchanges and more than 13,600 different simulated parts of interchanges. An artificial neural network (ANN)-based model and a particle swarm optimization (PSO)-based model were developed, and therefore, predicting driving time was possible just based on basic simple traffic and geometrical properties of the interchange. The results of testing, validating, and statistical analysis depicted a proper and precise development of the models. Although the PSO-based models have higher RMSE values than ANN-based models, the models were reliable enough to use for predicting the driving time in four parts of interchanges.

A new type of electrodialysis mixed matrix (MM) cation exchange membrane was prepared by incorporating carbon nanofibers (CNFs) into membrane matrix. The microscopy images showed uniform surface for the membrane relatively. The use of CNFs into membrane body enhanced membrane surface hydrophilicity, potential, transport number, permselectivity, and ionic conductivity obviously, while water uptake decreased. The sodium flux was also enhanced by incorporation of CNFs into membrane matrix from 0 to 0.5%wt and 2 to 8%wt, while declined for the samples in the range of 0.5 to 2%wt CNF ratios. Compared to pristine membrane, a smoother surface was observed for PVC-CNF membrane. Electrodialysis showed the (K+/Na+) flux ratio about 2.14. The transport mechanism of K+ and Na+ ions through the membranes discussed by considering ionic and hydrated radius, hydration potential, hydration free energy, entropy of hydration, and the Jones-Dole coefficient. Optimal performance was achieved for PVC-0.5%wt CNF membrane.

This research utilizes Bayesian network to address a range of possible risks to the electrical power system and its interdependent networks (EIN) and offers possible options to mitigate the consequences of a disruption. The interdependent electrical infrastructure system in Washington, D.C. is used as a case study to quantify the resilience using the Bayesian network. Quantification of resilience is further analyzed based on different types of analysis such as forward propagation, backward propagation, sensitivity analysis, and information theory. The general insight drawn from these analyses indicate that reliability, backup power source, and resource restoration are the prime factors contributed towards enhancing the resilience of an interdependent electrical infrastructure system.

Because ports are considered to be the heart of the maritime transportation system, thereby assessing port performance is necessary for a nation’s development and economic success. This study proposes a novel metric, namely, “port performance index (PPI)”, to determine the overall performance and utilization of inland waterway ports based on six criteria, port facility, port availability, port economics, port service, port connectivity, and port environment. Unlike existing literature, which mainly ranks ports based on quantitative factors, this study utilizes a Bayesian Network (BN) model that focuses on both quantitative and qualitative factors to rank a port. The assessment of inland waterway port performance is further analyzed based on different advanced techniques such as sensitivity analysis and belief propagation. Insights drawn from the study show that all the six criteria are necessary to predict PPI. The study also showed that port service has the highest impact while port economics has the lowest impact among the six criteria on PPI for inland waterway ports.

In the current research, the surface of a polyethersulfone (PES) nanofiltration membrane was modified by polyvinyl alcohol (PVA) and iron-oxide nanoparticles (Fe3O4) through a crosslinking reaction with glutaraldehyde (GA).The effect of the coating layer on the morphology, physico-chemical properties, separation and antifouling performance of the membranes was studied. The analysis of FTIR spectra, scanning electron microscopy (SEM), atomic force microscopy (AFM), porosity and mean pore size measurement, contact angle analysis, salt rejection and filtration of a powder milk solution was the basis of membrane characterization. Surface and cross-sectional SEM images showed the formation of a dense layer on the PES based NF membrane after coating. The pure water flux, porosity and mean pore size were decreased; the water contact angle was slightly lower due to the hydrophilic nature of PVA and Fe3O4 nanoparticles. The surface roughness initially decreased for a coating with a low concentration of nanoparticles but increased when a higher amount of nanoparticles was used. The salt rejection significantly increased from 68.4% for a bare PES membrane to 94% for the modified ones (sample 6) by surface modification. Filtration of a powder milk solution revealed the best antifouling performance for the membrane modified by PVA/Fe3O4 (2 wt %).

A novel high-flux emulsion polyvinyl chloride (EPVC) ultrafiltration membrane incorporated with different concentrations of boehmite nanoparticles was prepared. The modified EPVC membranes demonstrated enhanced hydrophilicity property and higher pure water flux and lower water contact angle because of the presence of hydrophilic boehmite in membrane matrix. The results showed that water flux was enhanced from 422.6 L m−2 h−1 for neat membrane to 701 4 L m−2 h−1 for 0.75 wt.% boehmite incorporated membrane at 2 bar. In addition, BSA flux growth of the optimum nanocomposite membrane in comparison with the neat one was 37.2%. BSA rejection for all nanocomposite membranes was above 98%.

As many large-scale systems age, and due to budgetary and performance efficiency concerns, there is a need to improve the decision-making process for system sustainment, including maintenance, repair, and overhaul (MRO) operations and the acquisition of MRO parts. To help address the link between sustainment policies and acquisition, this work develops a greedy heuristic-based local search algorithm (GHLSA) to provide a system maintenance schedule for multi-component systems, coordinating recommended component maintenance times to reduce system downtime costs, thereby enabling effective acquisition. The proposed iterative algorithm aims to minimize the sum of downtime, earliness and tardiness costs of scheduling, which contains three phases: (1) the construction phase, which uses a heuristic to construct an initial partial solution, (2) an improvement phase, which aims to improve the partial solution generated in the construction phase, and finally, (3) a local search phase, which performs a local search technique to the partial solution found in the improvement phase. The proposed algorithm makes a trade-off between exploration and exploitation of solutions. The experimental results for small (10 jobs) and large size (50 jobs) problems indicate that GHLSA outperforms both genetic algorithm and simulated annealing approaches in terms of solution quality and is similar in terms of efficiency.

Magnetic nickel ferrite (NiFe2O4) nanoparticles were synthesized and then modified by a novel hydrogel based on 2-acrylamido-2-methyl propane sulfonic acid (HAMPS). Field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR) analyses were conducted to prove the NiFe2O4/HAMPS nanocomposite formation decisively. The effect of NiFe2O4/HAMPS in the matrix of the heterogeneous cation exchange membrane on separation performance was studied. Adding of NiFe2O4/HAMPS into the membrane body up to 1%wt resulted in an increase of sodium flux obviously. The sodium flux showed a decreased trend at higher nanocomposite ratios slightly. Membrane potential, permselectivity, and transport numbers also showed improving trends. Results exhibited more value for Na+ dynamic transport numbers compared to static ones. Membrane water content and porosity increased from 13.07 to 27.7% and 9.6 to 20.2% by utilizing NiFe2O4/HAMPS, respectively. By adding NiFe2O4-HAMPS into the membrane structure a pronounced improvement in membrane mechanical resistance (~ 94%) and chemical stability was observed. Modified membrane containing 1.0%wt NiFe2O4-HAMPS showed effective separation in Pb2+ (~ 98%), Cu2+ (~ 48%), and Ni2+ (~ 34%) removal. This sample also showed highest current efficiency (78.9%) in Pb2+ removal and lowest energy consumption (6.97 W/mol) compared to others.

Fast charging sites play a crucial role for public acceptance of electric vehicle (EV). Selection of the most sustainable site positively contributes to the life cycle of electric vehicle charging station (EVCS), which requires considering some conflicting criteria. Previous researches mainly focused on utilizing optimization models to deal with EVCS site selection that only accounts for quantitative factors, while this paper proposes a Bayesian Network (BN) model that considers not only quantitative factors but also qualitative (subjective) ones. Based on academic literature and expert judgments, the assessment index for EVCS site selection was mainly made from sustainability point of view, which contains of economic, environmental, and social criteria with a total of eleven sub-criteria. BNs are powerful tools for handling risk assessment and decision making under uncertainty. The developed BN model is validated through sensitivity analysis approach. Finally, different propagation analyses have been performed to make special types of reasoning. This paper provides a new research perspective by considering uncertainty, qualitative and quantitative factors into the site selection assessment, and presents the mainstream penetration of BN as a powerful decision making tool in the context of electrical energy management.

Mixed matrix polyvinyl chloride-copper ferrite nanoparticles cation exchange membranes were prepared by casting solution technique. The effect of CuFe2O4 nanoparticles concentration on electrochemical properties of prepared membranes was investigated. The CuFe2O4 nanoparticles were synthesized by chemical precipitation technique. The formation of copper ferrite nanoparticles was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Scanning microscopy images showed uniform distribution of particles in the membrane matrix. Membrane surface hydrophilicity and charge density, membranes potential, transport number (> 97%) and permselectivity (> 96%) were enhanced by using CuFe2O4 nanoparticles in the membrane body. Also, ion exchange capacity and cation flux were increased initially by utilizing CuFe2O4 nanoparticles up to 1 wt% in the casting solution and then followed by a decreasing trend by adding more concentration up to 8 wt%. The PVC-CuFe2O4 membranes displayed lower electrical resistance (

Usage of eco-friendly refrigerants could be an effective solution to the global warming problem. However, a comprehensive assessment is necessary when selecting new refrigerants. Any substance should be evaluated for its overall impact on the global environment, energy efficiency, cost-effectiveness, and safety. This paper reviews the experimental and theoretical studies that have been carried out with environmentally friendly refrigerants such as hydrocarbons, hydrofluorocarbons, R744 (carbon dioxide), hydrofluoro olefin, and nanorefrigerants. The article's main aims are to evaluate the potential of all refrigerants used in the refrigeration and air conditioning industries and to present the primary applications of environmentally friendly refrigerants and nanorefrigerants. The paper also identifies the gaps in the literature and introduces opportunities for future work.

The use of membranes in desalination and water treatment has been intensively studied in recent years. The conventional membranes however have various problems such as uncontrollable pore size and membrane properties, which prevents membranes from quickly responding to alteration of operating and environmental conditions. As a result the membranes are fouled, and their separation performance is lowered. The preparation of smart gating membranes inspired by cell membranes is a new method to face these challenges. Introducing stimuli-responsive functional materials into traditional porous membranes and use of hydrogels and microgels can change surface properties and membrane pore sizes under different conditions. This review shows potential of smart gating membranes in water treatment. Various types of stimuli-response such as those of thermo-, pH-, ion-, molecule-, UV light-, magnetic-, redox- and electro-responsive gating membranes along with various gel types such as those of polyelectrolyte, PNIPAM-based, self-healing hydrogels and microgel based-smart gating membranes are discussed. Design strategies, separation mechanisms and challenges in fabrication of smart gating membranes in water treatment are also presented. It is demonstrated that experimental and modeling and simulation results have to be utilized effectively to produce smart gating membranes.

The ongoing COVID-19 pandemic has created a need for coatings that reduce infection from SARS-CoV-2 via surfaces. Such a coating could be used on common touch surfaces (e.g., door handles and railings) to reduce both disease transmission and fear of touching objects. Herein, we describe the design, fabrication, and testing of a cupric oxide anti-SARS-CoV-2 coating. Rapid loss of infectivity is an important design criterion, so a porous hydrophilic coating was created to allow rapid infiltration of aqueous solutions into the coating where diffusion distances to the cupric oxide surface are short and the surface area is large. The coating was deposited onto glass from a dispersion of cuprous oxide in ethanol and then thermally treated at 700 °C for 2 h to produce a CuO coating that is ≈30 μm thick. The heat treatment oxidized the cuprous oxide to cupric oxide and sintered the particles into a robust film. The SARS-CoV-2 infectivity from the CuO film was reduced by 99.8% in 30 min and 99.9% in 1 h compared to that from glass. The coating remained hydrophilic for at least 5 months, and there was no significant change in the cross-hatch test of robustness after exposure to 70% ethanol or 3 wt % bleach.

This paper deals with the problem of voltage and frequency restoration in droop-controlled inverter-based islanded microgrids (MGs). The problem is solved using a novel tracking consensus secondary control protocol based on the sliding-mode approach, which not only guarantees the exact finite-time restoration among voltages and frequencies of an inverter-based islanded microgrid, but also preserves the active power sharing among distributed generations (DGs). For each distributed generator with no direct access to reference values, a finite-time distributed estimator is locally designed and implemented in each DG unit to provide the reference value of frequency and voltage in a finite time. Lyapunov analysis is employed to verify the associated stability and fast convergence time of the proposed controller. Finally, simulation results are are presented and analyzed to confirm the effectiveness of the proposed approach.

Low-power cryogenic LNAs are required for readout of fault-tolerant quantum processors, which may have a million or more qubits. While InP HEMT LNAs are used for qubit readout today, SiGe HBTs are attractive for future systems due to their excellent noise and potential for low power operation. Here, we optimize a high performance SiGe technology to further improve its cryogenic noise properties. After extracting simulation models from standard and optimized HBT test structures, we employ these transistors in cryogenic LNAs and show that the cryogenic noise achieved with the optimized transistor is significantly better than that achieved using the standard device. Moreover, while dissipating just 1mW, the amplifier using the optimized HBT had an average measured $T$ e of 3.2 K from 4–8 GHz, which is more than 2 × better than the previous state-of-the-art SiGe LNA operating in this band.

SARS-CoV-2, the virus that causes the disease COVID-19, remains viable on solids for periods of up to 1 week, so one potential route for human infection is via exposure to an infectious dose from a solid. We have fabricated and tested a coating that is designed to reduce the longevity of SARS-CoV-2 on solids. The coating consists of cuprous oxide (Cu2O) particles bound with polyurethane. After 1 h on coated glass or stainless steel, the viral titer was reduced by about 99.9% on average compared to the uncoated sample. An advantage of a polyurethane-based coating is that polyurethane is already used to coat a large number of everyday objects. Our coating adheres well to glass and stainless steel as well as everyday items that people may fear to touch during a pandemic, such as a doorknob, a pen, and a credit card keypad button. The coating performs well in the cross-hatch durability test and remains intact and active after 13 days of being immersed in water or after exposure to multiple cycles of exposure to the virus and disinfection.

In this study, L-cysteine functionalized POSS nanoparticles were synthesized. The synthesized nanoparticles and methyl-methacrylate were applied to fabrication of polyether-imide-thin film nanocomposite nanofiltration membrane. The ratio of (MMA: NPs) changed to obtain efficient separation performances and good antifouling properties. Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and atomic force microscopy (AFM) analysis were used in membranes characterization. Pure water flux, Na2SO4, CrSO4, Pb(NO3)2 and Cu(NO3)2 rejection, membrane porosity, mean pore size of membrane and water contact angle were studies. Pure water flux measured 14.3 (L/m2.h) for neat membrane whereas that was 11–70.6 for thin-film membranes. Surface hydrophilicity enhanced and roughness, pore size and porosity decreased by increase of MMA:NPs ratio. The highest Na2SO4, CrSO4, Pb (NO3)2 and Cu(NO3)2 rejection observed 84%, 81%, 83% and 79%, at 0.03 wt.% of MMA:NPs ratio. FRR% measured ~95% at 0.03 wt.% of MMA:NPs ratio whereas it was ~29 for neat membrane.

This paper proposes a novel robust decentralized charging strategy for large-scale EV fleets. The system incorporates multiple EVs as well as inelastic loads connected to the power grid under power flow limits. We aim at minimizing both the overall charging energy payment and the aggregated battery degradation cost of EVs while preserving the robustness of the solution against uncertainties in the price of the electricity purchased from the power grid and the demand of inelastic loads. The proposed approach relies on the so-called uncertainty set-based robust optimization. The resulting charge scheduling problem is formulated as a tractable quadratic programming problem where all the EVs' decisions are coupled via the grid resource-sharing constraints and the robust counterpart supporting constraints. We adopt an extended Jacobi-Proximal Alternating Direction Method of Multipliers algorithm to solve effectively the formulated scheduling problem in a decentralized fashion, thus allowing the method applicability to large scale fleets. Simulations of a realistic case study show that the proposed approach not only reduces the costs of the EV fleet, but also maintains the robustness of the solution against perturbations in different uncertain parameters, which is beneficial for both EVs' users and the power grid.

International audience; The ripple effect could occur when a disruption in supplier base cannot be localised and its consequences propagate downstream the supply chain (SC) adversely affecting the performance. While stress-testing of SC designs and assessment of their vulnerability to disruptions in single-echelon-single-event setting is desirable and indeed critical for some firms, modeling the ripple effect impact in multi-echelon-correlated-events systems is becoming increasingly important. Notably, ripple effect assessment in multi-stage SCs is particularly challenged by consideration of both vulnerability and recoverability capabilities at individual firms in the network. We construct a new model based on integrating Discrete-Time Markov Chain (DTMC) and Dynamic Bayesian Network (DBN) model to quantify the ripple effect. We use DTMC to model the recovery and vulnerability of suppliers. The proposed DTMC model is then equalized with a DBN model in order to simulate the propagation behavior of supplier disruption in the SC. Finally, we propose a metric that quantifies the ripple effect of supplier disruption on manufacturer in terms of total expected utility and service level. The ripple effect measure constructed is examined and tested using two case-studies. The findings suggest that our model can be of value in revealing latent high-risk paths in the SC, analysing the performance impact of both a disruption and its propagation, and prioritizing the contingency and recovery policies.

Electrodialysis-mixed matrix tris(8-hydroxyquinolinato)aluminum (AlQ3) nanoparticles entrapped heterogeneous cation-exchange membrane was prepared by the solution casting technique. The effect of the concentration of AlQ3 in the casting solution on the physico-chemical properties of the homemade membranes was studied. AlQ3 nanoparticles were synthesized via a simple precipitation method and characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction. The use of AlQ3 nanoparticles in the membrane matrix led to an increase of the membrane electrical conductivity and surface hydrophilicity. The membrane ion-exchange capacity was enhanced by using AlQ3 loading ratios up to 1.5 wt%; the IEC decreased for concentrations above 1.5 wt%. The increase of AlQ3 content ratios up to 0.5 wt% in fabricated membrane initially caused to increase of water content. The membrane water content was decreased for the concentrations between 0.5 to 1.5 wt% and then showed an increasing trend again at higher additive loading ratios. The membrane potential, charge density, permselectivity, and transport number were improved obviously by the use of AlQ3 nanoparticles in membrane body. The ion flux/permeability enhanced sharply by using of AlQ3 up to 0.5 wt% in the membrane matrix and then began to decrease while the additive concentration was more than 0.5 wt%.

In this study, the influence of various weight ratios of activated carbon (AC)-co-chitosan (CS) composite nanoparticles in the matrix of ion exchange membranes was examined to adapt their electrochemical characteristics based on the combination of high surface area and adsorptive property of activated carbon nanoparticles and the hydrophilicity and functionality of chitosan. Scanning electron microscopy (SEM), scanning optical microscopy (SOM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD), water content, ion exchange capacity (IEC), water contact angle, membrane potential, transport number and permselectivity, sodium flux, and membrane electrical resistance were used in membrane characterization. The fabricated membranes were also utilized in copper removal from water. The SEM and SOM images exhibited a uniform distribution of nanoparticles (NPs) on the surface of membranes. The membrane surface hydrophilicity was decreased; surface roughness and water content increased by utilizing AC-co-CS composite NPs. Membrane IEC was initially enhanced by utilizing composite NPs up to 0.5% wt and then decreased by more increase in additive ratios from 0.5 to 2%. Increasing trend was observed again at higher NPs concentration. Similar trend was also found for sodium flux. Membrane potential, t-number, permselectivity, and membrane electrical resistance initially represented an enhancing trend by use of AC-co-CS composite NPs up to 0.5% wt in membrane body and then decreased by more increase of NPs concentration from 0.5 to 8% wt. The fabricated membranes containing AC-co-CS nanoparticles showed good capacity in Cu removal from water. Membrane mechanical strength was improved initially by utilizing AC-co-CS composite NPs and then decreased at high additive concentration.

In this study, bis (8-hydroxyquinoline) zinc (ZnQ2) nanoparticles were synthesized and used in heterogeneous cation exchange membranes. The resulting membranes were examined in terms of membrane morphology and electrochemical features. Scanning electron microscopy (SEM) images, Fourier transform infrared (FTIR) spectra and X-ray diffraction (XRD) patterns confirmed the successful formation of ZnQ2 nanoparticles. Scanning Optical Microscopy (SOM) images of the prepared membranes showed a relatively uniform membrane surface. It was found that membrane water uptake and surface hydrophilicity were enhanced in the presence of ZnQ2 nanoparticles. The membrane potential, transport number and permselectivity were also improved by increasing the additive concentration up to 8 wt% and then showed a decreasing trend. In addition, the sodium permeability/flux, electrical conductivity and mechanical stability were significantly increased by using ZnQ2 content ratios up to 4 wt% and then declined by a further increase of the concentration from 4 to 16 wt%. Furthermore, the modified membranes containing ZnQ2 showed a rougher surface slightly compared to pristine membrane.

In this work, novel nanofiltration membranes with outstanding performance and antifouling properties were fabricated by incorporating composite graphene oxide/chitosan (GOC) nanoplates into the membrane structure. GOC composite nanoplates were prepared by surface modification of GO with chitosan. The GOC nanoplates were then introduced as additives in a polymeric phase in different concentrations (up to 1%) in view of membrane synthesis. these membranes were thoroughly characterized and assessed for their Na2SO4 and CrSO4 rejection and water flux. Furthermore, the antifouling performance of GO and GOC filled membranes in high concentration (1 wt%) was investigated. Modified membranes with addition of GOCs showed a higher hydrophilicity, pure water flux and rejection, and a smoother surface compared to a bare PES and a GO incorporated membrane. SEM surface images indicated a more uniformed distribution of GOCs at a high loading rate (1 wt%) compared to GO. Due to the uniform dispersion of GOCs, a better antifouling performance was observed than for GO filled membranes. The results indicate that surface modification of GO with chitosan can enhance the membrane performance and properties, due to availability of sites with higher activity.

Membrane-coated tables were prepared to control the release rate of aluminum phosphide from rice tablets when this tablet comes into contact with water in the stomach. Mixed matrix polyvinyl chloride-co-activated carbon nanoparticles (ACNPs) membranes was used as a thin film to coat the rice tablets. The effect of ACNPs as additive in membrane matrix on release behavior of aluminum phosphide was evaluated. The scanning electron microscopy (SEM) images and X-ray diffraction patterns showed that nanoparticles are uniformly distributed in the prepared coatings. The membrane water contact angle was enhanced from 55° to 80° in the presence of ACNPs. The tear resistance of the prepared membranes was also improved from 4.34 to 5.01 (grf/mic) by using ACNPs. The membrane-coated tablets showed a controlled aluminum phosphide release rate compared to pristine rice tablet without cover. The fastest aluminum phosphide release rate for all samples is related to the first five days. In addition, the half-time and life-time of membrane-coated tablets were declined by an increase of the ACNPs ratio up to 15 wt%. Swelling of the fabricated cover in aqueous environment led to a decrease of the aluminum phosphide release rate.