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Introduction: Oxidative stress is involved in many diseases, including hypertension, kidney failure, and heart disease. This study aimed to evaluate the effect of hydroalcoholic Cichorium intybus extract on blood pressure in rats. Antioxidant activity, phenolic and flavonoid contents of the plant extract were also evaluated. Methods: In this study, 32 male Wistar rats weighing 250-300 g were divided into four groups of eight each. Animals in the control group were administered with normal saline and in the C. intybus groups with extract at 25, 50, and 100 mg/kg for two weeks. Then, the homodynamic parameters were examined by the Power lab. The phenolic and flavonoid contents were also evaluated by a spectrophotometer and the rate of free radical scavenging activity was measured by the diphenyl-1-picyryl-hydrazyl (DPPH) free radical method. Results: The free radical scavenging activity of C. intybus extract was obtained 47.85% of DPPH, and flavonoid and phenolic contents were 8.21 and 27.19 mg/g of dry extract, respectively. Meanwhile, median (MAP), systolic (SAP) and diastolic arterial pressure (DAP) significantly decreased in the 50 mg/kg extract-treated group compared to the control and 200 mg/kg extract-treated groups. Conclusion: Ethanol extract of C. intybus plays a protective role against hypertension, which, in part, might be due to antioxidant compounds of the plant against free radicals.

In this study, a novel sorbent based on phenylsulfonic acid functionalized multiwall carbon nanotubes (MWCNTs-Ph-SO3H) was used for preconcentration and separation of trace Ni(II) ions in petrochemical wastewater samples by ultrasound-assisted solid-liquid trap phase extraction. In this work, a mixture of MWCNTs-Ph-SO3H as a nanosorbent and ionic liquid (1-hexyl-3-methylimidazolium hexafluorophosphate, IL) dispersed in acetone was rapidly injected by a syringe into 50 mL of a sample containing Ni(II). The metal was extracted by sulfonate group as (RSO3)2-Ni at optimized pH. After shaking and centrifuging, the nanoparticles of sorbent were trapped in IL phase and settled down in a conical centrifuge tube (IL/MWCNTs-Ph-SO3H). Hydrophobic IL was used to fast trap the Ni(II) loaded sorbent from the sample solution. Under the optimized conditions, the linear range (peak area), limit of detection and enrichment factor were obtained as 1.5–165 μg/L, 0.35 μg/L and 50, respectively.

In this research, a zinc oxide/copper oxide/graphene oxide (ZnO/CuO/GO) nanophotocatalyst was synthesized for photodegradation of aniline as a pollutant, upon exposure to ultraviolet light (UV). Three variables including initial aniline concentration, the nanophotocatalyst dosage, and pH were designed. The statistical test and optimal conditions were determined. The consequences specified that the optimum values of pH, initial aniline concentration, the dosage of nanophotocatalyst, and the reaction time were 6, 150 ppm, 1 g/L, and 3 h, respectively. The obtained results revealed that the photodegradation of aniline was enhanced with doping zinc oxide and CuO on the graphene oxide. Under optimal conditions, 97% photodegradation of aniline was observed. The mechanism of aniline degradation with nanophotocatalyst was evaluated by molecular dynamic (MD) graphs. The interactions between nanophotocatalysts and aniline were considered by energy, density graph.

Comprehensive structural/molecular simulations have been undertaken to study the poly(benzimidazoles) (PBI) membrane combined with four different nano-oxide materials (ZnO, Al2O3, SiO2 and TiO2) for purification and production of hydrogen from natural gases. Composite membranes were built with different amounts of nano-oxide materials to investigate the influence of nano-oxide content on the PBI membrane performance. Several structural characterizations such as FFV, WAXD and also a thermal one (glass transition temperature) were done to study the structural properties of all simulated membrane cells. Moreover, MSD and adsorption isotherms tasks were used to estimate the diffusivity and solubility of hydrogen molecules through the latter mixed matrix membranes (MMMs), respectively. Permeability and permselectivity of H2 penetrate molecules were also carefully calculated using the aforementioned penetrating factors (diffusivity and solubility). Results show a significant improvement in structural and transport properties by increasing the nanomaterials content, which could be due to the growth of penetration pathways through the membranes. Furthermore, membranes with SiO2 yield the best results compared to other three nano-oxide fillers. H2 gas yields the best results that help the storage and separation of this precious gas from other gas molecules, which present in natural gases. Compared to the previous studies and literature results, the current results are accurate and reliable to describe the structural and transport properties of PBI/nano-oxides composites.

In this study, novel chitosan/silica mixed matrix membranes were prepared by 10 wt% loading of TEOS and APTEOS into chitosan matrix and simultaneously results were simulated by molecular simulation methods to investigate the reliability of the experiment results. The fabricated membranes were structurally characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and operationally evaluated by ethanol dehydration permeation tests. SEM analysis showed a uniform distribution of silica nanoparticles in the polymer matrix. FTIR analysis indicated that, compared to the neat membrane, the presence of APTEOS and TEOS initiators caused formation of stronger bonds of hydroxyl (OH) and amino (NH) groups. The XRD test was also done by molecular simulation to investigate the crystallinity of the simulated membranes. Results revealed that membrane containing APTEOS was more amorphous than membrane containing TEOS. Also, the glass transition temperatures the membranes containing APTEOS and TEOS was calculated to be 162 and 160.8 °C, respectively. Permeation test results indicated that for both membranes the permeation flux increased and separation factor decreased with temperature. The maximum flux and best separation factor for CS/APTEOS and CS/TEOS were obtained at 70 °C and 30 °C, respectively. Chitosan/TEOS membrane showed the best separation factor of 450 in 30 °C, while for Chitosan/APTEOS membrane this value was less than 400. CS/APTEOS membrane showed better pervaporation separation index (PSI); however, the results showed that separation index of both membranes, which was initially more than 320 in 30 °C, decreased with temperature and reached to less than 130 in 70 °C. Also, the simulation results were in good agreement with experiment results.

Molecular simulation has been undertaken to study the structural and transport properties of Poly (amide-6-b-ethylene oxide) (PEBA 1657)/Faujasite (FAU) mixed matrix membranes. Membranes were built with different amounts of FAU nanomaterials to investigate the influence of nanomaterial content on the membrane performances. Structural characterizations such as ractional free volume (FFV), radial distribution function (RDF), wide angle XRD (WAXD) and glass transition temperature were done on the simulated membrane cells to study their structural properties. Also, by using MSD and adsorption isotherms, diffusivity and selectivity of these membranes were measured, respectively. The two main transport factors (permeability and permselectivity) were examined using calculated diffusivity and solubility, and the membrane properties were investigated at two different operating temperatures (298 K, 318 K). Results show that by increasing the nanomaterials content, structural properties improve and transport properties increase which is due to the increase of the pathways for penetrant molecules to move through the membranes. Compared to the published results, the current simulation study is more accurate in describing the structural and transport properties of PEBA/FAU mixed matrix membranes. It was found that increasing the FAU content from 0 to 20 wt% increased the permeability of the membrane to CO2, as well as the permselectivity for CO2/NO2 from 69.4 barrer to 89.23 barrer at 298 K. This change in FAU content also decreased the glass transition temperature from 212 K to 204.1 K.

In this study, structural and transport mechanism and properties of two kinds of polyether block amide (PEBA 1657, PEBA 2533) membrane in presence of POSS-PEG functionalized nanoparticles were investigated by molecular dynamic simulation (MD). Monte Carlo technique was used to investigate transport properties of the simulated membranes. The wide-angle XRD (WAXD), mean square displacement (MSD), glass transition temperature (Tg) and sorption isotherm were studied to investigate the aforementioned mixed matrix membranes. Also, solubility, diffusivity, permeability and permselectivity of light gases (N2, CO2, CH4, O2, and H2) were investigated carefully by Materials Studio simulator. The results showed higher permeability for membranes with PEBA 2533 rather than the ones with PEBA 1657; this conclusion is also confirmed with the experimental results which are reported in the literature. But, for the permselectivity of membranes, the results were opposite of the permeability results. Tg for all membranes decreased by increasing the POSS-PEG nanoparticle content. Additionally, by comparing the results of the simulations with the results of literature, it is revealed that simulation results were in acceptable agreement by experiment results.

In this communication, structural-transport-properties of polyether block amide (PEBA)-MFI zeolite mixed matrix membranes (MMMs) have been investigated with molecular simulation (MS) and Monte Carlo (MC) technique. The density profile, RDF, FFV and XRD characterization have been calculated to investigate the aforementioned MMMs microstructure and also sorption and diffusion structural dependence of CO 2 –CH 4 and CO 2 –N 2 pairs. Sorption, diffusion, permeability and selectivity of natural gases including CO 2 , CH 4 and N 2 by PEBA polymeric membrane filled with nano-zeolite (MFI type) have been examined to study the influence of MFI nanomaterial and nanomaterial loading content on the performance of the MMMs. By increase of MFI loading from 10 to 20 wt.%, permeability for CO 2 , CH 4 and N 2 increases from 106.5 to 123.6, 4.75–4.74 and 1.28 to1.31, respectively. Structural analysis shows very good behavior for simulated membranes. Moreover, experiments show that simulation results for XRD and diffusivity are in good agreement with experiment results.

In the present study, nano-sized Pt/WO3-carbon nanofiber, Pt-Pd/WO3-carbon nanofiber and Pt-Ru/WO3-carbon nanofiber electrocatalysts were synthesized and the performance of prepared catalysts were compared with catalysts coated carbon black for the oxygen reduction reaction (ORR). The morphology and structure of prepared catalysts were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The SEM images showed that the catalyst nanoparticles were well dispersed on the both carbon nanofiber and carbon black supports. Electrochemical measurements including linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA) tests were applied to investigate the potential of the fabricated electrodes on the ORR. The results demonstrated that the catalysts based on carbon nanofibers showed a significant increase of activity toward the ORR. Also, the Pt/Pd coated carbon nanofibrous electrode showed the highest electrochemical activity.

Porous stainless steel/NaX nanozeolites/Palladium (Pd)/TiO 2 (PSS/NaX/Pd/TiO 2 ) membrane was prepared by sol–gel method and its application was investigated for hydrogen separation. NaX nanozeolites were synthesized using microwave heating method and coated by vacuum-assisted method on the PSS surface. The prepared membranes were characterized using SEM, and XRD analysis. The Box-Behnken design was used to determine the relation between synthetic and process variables including NaX content (0.5–1.5 g), Pd/TiO 2 percentage (2–10%), pressure difference (2–4 bar) and temperature (350–450 °C) on the hydrogen permeation flux and H 2 /N 2 ideal selectivity. By optimization of parameters, the experimental maximum hydrogen permeation flux and ideal selectivity were found to be 0.245 mol/m 2 s and 1025, respectively. Moreover, the performance of fabricated PSS/NaX/Pd/TiO 2 membrane was investigated for different mixtures of H 2 /N 2 in optimum conditions. The results indicated that hydrogen fluxes and H 2 /N 2 separation factor were remarkably decreased by increasing N 2 content. The obtained results suggests that the incorporation of Pd/TiO 2 composite into the Pd-based membranes and optimization of parameters can be effective method for increasing the performance of Pd-based membranes in hydrogen separation.

Nanocellulose (NC) films are considered as a prospective alternative to non-sustainable packaging materials, however, their higher embodied energy and limited moisture barrier properties are regarded as a huge constraint regarding their commercialization. This study aims to produce films with relatively low environmental impact and improved barrier performance. For this purpose, carboxymethyl cellulose (CMC) and NC were combined, and this resulted in multidimensional advantages. The mass production of films could be achieved in only 2 h (requiring at least 24 h under ambient conditions) when dried in an oven at 75 °C with enhanced mechanical properties and without compromising their dimensional stability. The moisture barrier properties of the NC/CMC films were improved up to 92 % compared with the NC films alone and the results achieved are comparable with packaging materials such as polyethylene terephthalate (PET), polycarbonates (PC) etc. Finally, the NC/CMC (1:1) films have low environmental impact compared with PET films.

Advances in nanotechnology and nanomaterials have led to the development of nanostructured membranes. Zinc oxide (ZnO), a multifunctional nanomaterial, has been postulated as a filler in polymeric and ceramic membranes to improve properties such as roughness, permeability, and fouling resistance. This review is a comprehensive overview of recent progress on the following: i) ZnO nanostructure preparation and characterization, ii) ZnO growth techniques, iii) fabrication of ZnO-based polymeric and ceramic membranes and iv) environmental application studies in water and wastewater technologies using ZnO-embedded polymeric and ceramic membranes. The review also covers approaches to control membrane properties to reduce fouling and biofouling, increase the solvent flux, increase pollutant rejection, and control swelling and deswelling membrane properties. Finally, the main expected applications on membrane-driven processes for environmental applications of water treatment are also analysed.

Palladium (Pd) membranes on porous stainless steel (PSS) were prepared by electroless plating. An intermediate layer of NaX nanozeolite was employed to modify the pore size of the PSS support and improve the hydrogen permeability. NaX nanozeolites were synthesized using convectional hydrothermal method. The NaX intermediate layer was coated by vacuum-assisted method on the PSS surface. The structure and morphology of the prepared membranes were characterized using SEM, XPS and XRD analysis. Permeation measurements were conducted using H 2 , N 2 and mixture of H 2 /N 2 at different temperatures (350–450 °C), and trans-membrane pressures (4–8 bar). The results indicated that the permeability and hydrogen selectivity were increased by enhancement in temperature and pressure. The hydrogen fluxes in H 2 /N 2 mixtures were lower than those corresponding to pure hydrogen at the same partial pressures and temperatures. The obtained results suggests that the use of NaX nanozolite is an effective intermediate layer in Pd/PSS membranes for hydrogen separation.

Molecular dynamics (MD) and Monte Carlo (MC) simulations have been used to study the PEBA 1074-PEG 400 blended membranes. By blending the membranes and TiO2 nanomaterials, separation of CO2 gas from CH4 (which represents the natural gas) has been investigated. Structural analysis including WAXD, XRD, FFV and glass transition temperature has been studied to check thermal and structural properties of total simulated membranes. In addition, the adsorption and MSD isotherms have been used to measure solubility and diffusivity through these mixed matrix membranes (MMMs), respectively. Finally, based on the solubility and diffusivity coefficients, permselectivity and permeability of these gas molecules were measured. By increasing the PEG 400 and nanomaterials content, remarkable advance was observed in the transport properties of membranes, i.e. membranes permeability after addition of 40 wt% of PEG 400 and 8 wt% of TiO2 became 47 barrer and 143 barrer, respectively. Also, the PEBA 1074/40 wt% PEG/8 wt% TiO2 composite was selected as the optimum membrane in this study.