Photocatalysis of xenobiotic organic compounds in greywater using zinc oxide nanoparticles: a critical review

The direct discharge of raw bathroom greywater has increased the concentrations of various pollutants in the water bodies. Typically, greywater contains large quantities of xenobiotic organic compounds (XOCs) owing to an increase in consumption of personal care and bath products. Therefore, it urges for a suitable technology to eliminate these compounds from contaminated waters. Photocatalytic degradation using Zinc Oxide nanoparticles (ZnO NPs) has the potentiality to eliminate various XOCs. However, ZnO NPs have high tendency to aggregate, which may lower the photocatalytic degradation rate. Therefore, there is an urgency to modify ZnO NPs to overcome the limitation. The present review was conducted to determine a suitable method for the modification ZnO NPs. Besides, the potential of the modified ZnO NPs in degrading XOCs in greywater as a photocatalyst was also discussed.     

Functionalization of poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) films via surface‐initiated atom transfer radical polymerization: Comparison with the conventional free‐radical grafting procedure

We modified hydrophobic poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBHV) films with hydrophilic chains to control their surface properties. We designed and investigated surface‐initiated atom transfer radical polymerization (SI‐ATRP) to modify the PHBHV films by grafting poly(2‐hydroxyethyl methacrylate) (PHEMA) from the surface. This method consisted of two steps. In the first step, amino functions were formed on the surface by aminolysis; this was followed by the immobilization of an atom transfer radical polymerization initiator, 2‐bromoisobutyryl bromide. In the second step, the PHEMA chains were grafted to the substrate by a polymerization process initiated by the surface‐bound initiator. The SI‐ATRP technique was expected to favor a polymerization process with a controlled manner. The experimental results demonstrate that the grafting density was controlled by the reaction conditions in the first step. The grafted films were analyzed by Fourier transform infrared spectroscopy, contact angle testing, scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy. The results show that grafted chains under the SI‐ATRP method were preferentially located on the surface for surface grafting and in the bulk for conventional free‐radical polymerization initiated by benzoyl peroxide. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Selective nanofiber deposition via electrodynamic focusing

In this paper, we demonstrate the effect of electrodynamic focusing through a gold-coated PDMS shadow mask on the selective deposition of electrospun nanofibers. Under a suitable applied voltage, the PDMS mask repels the fibers from its surface while simultaneously forcing them into micron-sized holes and onto a collecting substrate. The presented technique is simple and can be used to produce lithographic-scale nanofiber deposition using a wide range of materials.     

Sonochemical Synthesis of Two New Nano-structured Cadmium(II) Supramolecular Complexes

Nano-particles of two new Cd(II) supramolecular complexes, [Cd(4,4-di-tert-bubipy)Cl₂(DMSO)] (1) and [CdI₂(4,4′-dmbpy)(DMSO)] (2) have been synthesized by sonochemical process and characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. The structure of compound 1 has been characterized by single crystal X-ray diffraction. The prepared nano-structure was characterized by scanning electron microscopy and X-ray powder diffraction. The nano-structures of supramolecular complexes have been synthesized with calcination of complexes at oleic acid as a surfactant at 190 ºC too. The size of the samples prepared by sonochemical method and calcination are about 30–40 and 40–50 nm respectively.     

Buckling and postbuckling behavior of unstiffened slender curved plates under uniform shear

Buckling and postbuckling behavior of curved plates under in-plane shear are investigated. After revisiting classic elastic buckling results, the elastoplastic postbuckling behavior and the effects of curvature parameter and aspect ratio are simulated via geometrical and material nonlinear analyses. Imperfection sensitivity is studied for various imperfection shapes and magnitudes. An increase in curvature parameter raises the elastic buckling load, produces unstable buckling and reduces postbuckling reserves. The buckling load and shear capacity are higher in shorter plates. Small initial imperfections are found to have severe effects on the initial buckling load of plates with large curvature parameter, but little effect on ultimate postbuckling capacity.     

Design of highly tough poly(l‐lactide)‐based ternary blends for automotive applications

Technical renewable poly(l ‐lactide) (PLA)‐based blends represent an elegant way to achieve attractive properties for engineering applications. Recently, the miscibility between PLA and poly(methyl methacrylate) (PMMA) gave rise to new formulations with enhanced thermo‐mechanical properties but their high brittleness still remains a challenge to be overcome. This work here focuses on rubber‐toughened PLA/PMMA formulations for injection‐molding processes upon the addition of a commercially available ethylene‐acrylate impact modifier (BS). The miscibility between PLA and PMMA is not altered by the presence of BS but the incorporation of BS (17% by weight) into a PLA/PMMA matrix could enhance both ductility and toughness of PLA/PMMA blends for PMMA content up to 50 wt %. An optimum range of particle sizes (d_n ～0.5 µm) of the dispersed domains for high impact toughness is identified. These bio‐based ternary blends appear as promising alternatives to petro‐sourced blends such as ABS‐based blends in engineering injection‐molding parts. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43402.     

Preparation,optimization, and characterization of simvastatin nanoparticles by electrospraying: An artificial neural networks study

The purpose of this study was to determine major factors impacting the size of simvastatin (SIM)‐loaded poly(d , l ‐lactic‐co‐glycolide) (PLGA) nanoparticles (NPs) that was prepared using electrospraying. Three variables including concentration of polymer and salt as well as solvent flow rate were used as input variables. Size of NPs was considered as output variable. For the first time, our findings using a systematic and experimental approach, showed the importance of salt concentration as the dominant factor determining the size with a sharp and reverse effect. Optimum formulation (i.e., flow rate 0.08 mL h^?1, polymer concentration 0.7 w/v %, and salt concentration 0.8 mM) was then evaluated for aqueous solubility, encapsulation efficiency, particle size, in vitro drug release pattern and cytotoxicity. A very appreciable encapsulation efficiency (90.3%) as well as sustained release profile, considerable enhancement in aqueous solubility (～5.8 fold) and high IC₅₀ (>600 µM of SIM‐loaded PLGA NPs) indicated PLGA as a promising nanocarrier for SIM. The optimum formulation had particle size, zeta potential value, polydispersity index (PDI) and drug loading of 166 nm, +3 mV, 0.62 and 9%, respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43602.     

Investigating the characteristics of two different methods in nanofiber yarn coloration

Today nanofibers are used widely in a variety of applications. Among many investigations of nanofiber characteristics, their color features have been studied scarcely. In this study, nanofiber yarns were colored using two different methods: exhaustion dyeing and colored solution electrospinning or dope dyeing. In the first method, nylon66 nanofiber yarns were produced and then dyeing process was followed at different dye concentrations. In the second method, colored nanofiber yarns were produced directly using the yarn electrospinning setup. Through the spectrophotometric measurements, it was illustrated that the color saturation increases by increasing the dye content in the dyeing bath and electrospinning colored solution. At the end, the nanofiber yarns with equal dye content were produced using two mentioned methods. It was observed that the color strength of dope-dyed samples was lower than the dyeing process samples, but their levelness was better than the samples of dyeing process. Chromatic values showed that the produced nanofiber yarns with equal dye content using different methods have different hues.