Dual-functioning core@shell nanofiber strip for enhancing drinking water quality: Polysulfone/graphene oxide adsorbent core layer and polyvinylpyrrolidone/mint sacrificial shell layer

Drinking water quality is considered a continuing concern of human health. Herein, for the improvement of water quality, dual functioning core-shell (CS) nanofibers were developed by use of polysulfone (PSU)/graphene oxide (GO) as the adsorbent core layer for removing heavy metal ions and polyvinylpyrrolidone (PVP)/mint extract as the shell layer for inducing antioxidant activity to the water. Various analyses on the strip samples before and after the water treatment experiment were performed. ATR-FTIR by appearing or disappearing chemical bonds, TEM micrographs based on the formation of shell layer around the nanofibers, FESEM according to the uniformity and diameter of nanofibers, and EDX analysis based on the elemental and mapping results, verified the core-shell structure of nanofibers. The results of the antioxidant activity demonstrated that after the dissolution shell layer, radical scavenging capability of water was improved effectively. Thereafter, the remained core layer had a high capacity and efficiency for the adsorption of metal ions especially for CS3 with 70.9% and 58.7% efficiency for Fe(III) and Ni(II). By achieving 0.975 and 0.568 L/g partition coefficient (PC), the desired performance of CS3 (core layer: 15 wt% PSU, 0.5% GO and shell layer: 5 wt% PVP, and 2.5 wt% mint) was confirmed.     

Hydrogen-rich syngas production via integrated configuration of pyrolysis and air gasification processes of various algal biomass: Process simulation and evaluation using Aspen Plus software

In the present study, hydrogen-rich syngas production via integrated configuration of pyrolysis and air gasification processes of different algal biomass is investigated at relevant industrial condition. A comprehensive steady state equilibrium simulation model is developed using Aspen Plus software, to investigate and evaluate the performance of pyrolysis and air gasification processes of different algal biomass (Algal waste, Chlorella vulgaris, Rhizoclonium sp and Spirogyra). The model can be used as a predictive tool for optimization of the gasifier performance. The developed process consists of three general stages including biomass drying, pyrolysis and gasification. The model validation using reported experimental results for pyrolysis of algal biomass indicated that the predicted results are in good agreement with experimental data. The effect of various operational parameters, such as gasifier temperature, gasifier pressure and air flow rate on the gas product composition and H₂/CO was investigated by sensitivity analysis of parameters. The achieved optimal operating condition to maximize the hydrogen and carbon monoxide production as the desirable products were as follows: gasifier temperature of 600 °C, gasifier pressure of 1 atm and air flow rate of 0.01 m³/h.     

Synthesis and characterization of conductive neural tissue engineering scaffolds based on urethane-polycaprolactone

Polymeric biomaterials play a key role in enhancement of lengthy nerve regeneration and various types of scaffolds were used to pave the way for nerve regeneration. Electrospun fibrous scaffolds have special potential applicability in controlling the cell behaviors such as adhesion, growth, proliferation and function. This study attempted to design a conductive and porous fibrous scaffold containing polycaprolactone (PCL) and polyaniline (PANI) with controllable degradation rate by adding urethane groups in scaffold structures. FTIR and NMR analysis was used to characterize the chemical bonds. Morphology, porosity, conductivity and degradation rate of scaffolds were also evaluated. To assess the cell–scaffold interaction, PC-12 cell line was cultured on the scaffolds. Results showed that the degradation rate of composite samples significantly increased in 50 time period. It seems that these results suggest that the composite fibrous scaffolds having proportions of UPCL/PCL/PANI45:20:35 exhibit the most balanced properties that meet all of the required specifications for neural cells and possess a potential application in neural tissue engineering.     

Electro-conductive modification of polyethylene terephthalate fabric with nano carbon black and washing fastness improvement by dopamine self-polymerized layer

Modification of textiles with new applications target such as electroconductive fabrics has recently attracted researchers. In this article, carbon black nanoparticles (CB NPs) were applied to polyester fabric through two separate high temperature (HT) exhaustion processing with NaOH and cetyltrimethylammonium bromide (CTAB) as alkali hydrolysis catalyst and dispersing agents. To improve the stability of CB NPs on the fabric a self-polymerized compound, dopamine (DA) was used in a simple dipping method at room temperature for 24 h to form a thin layer of PDA on CB NPs-treated fabric. Field emission scanning electron microscopy (FESEM) was used to study the morphology of the fabrics confirming presence of CB NPs. EDX and mapping patterns showed the percentage and distribution of carbon, nitrogen, and oxygen elements on the fabric surface. The treated fabric indicated an electrical resistance of 14 kΩ turns a LED device on with a 10 V power supply. Self-polymerized DA on the fabric surface led to more nitrogen and oxygen caused higher CB NPs stability. Furthermore, the tensile strength results revealed a 25.8% lower tenacity on the treated fabric. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48035.