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Summary: In this study, styrene‐butadiene‐styrene (SBS) was used to develop a novel functionalized electrospun membrane for the effective treatment of heavy metals in direct contact membrane distillation (DCMD) applications. Functionalization was achieved by the addition (doping) of the super hydrophobic Al2O3 nanoparticles (Al NPs) within the matrix of the membrane during electrospinning. Neat (pristine nondoped) and doped SBS membranes were tested. The performance of the SBS membranes were also compared with fabricated polyvinylidene fluoride membranes with and without doping with Al NPs. The membrane characteristics were tested via Fourier transform infrared, scanning electron microscopy, pore size, and porosity investigations. The wettability of the membranes was investigated with respect to the liquid entry pressure (LEP) and contact angle. The performance of the membranes was tested in a DCMD setting for its ability to treat water containing salt (NaCl) and heavy metals (Cr (VI), Cd, Pb) in various concentration in a single and multicomponent systems. The SBS member exhibited excellent hydrophobicity characteristics such as a high LEP (16.87 psi) and contact angle (141° ± 2°). It also had superior permeate flux rate compared to the other prepared membranes (54.4 LMH). The addition of the Al2O3 nanoparticles enhance the performance of the membranes substantially. Slight decline in the flux was observed after 14 hours of continuous operating time that could be attributed to agglomeration, adsorption, or temperature polarization effects. The SBS AL NPs membranes also demonstrated excellent flux for saline solutions of varied concentrations with 99% salt rejection. [ABSTRACT FROM AUTHOR]

In this work, nine photocatalysts were prepared by a conventional solid-state reaction method. The samples were characterized by X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, surface area measurements based on the Brunauer-Emmett-Teller theory, and scanning electron microscopy. The tested materials (BaBiO3, Bi2WO6, SrTiO3, KNbO3, NaNbO3, Sr4Nb2O9, YInO3, CaIn2O4, and YFeO3) showed great potential for use as photocatalysts in the efficient reduction of CO2 into a renewable hydrocarbon fuel as well as in water splitting. Our results showed that among the nine tested photocatalysts, three could generate CH4. In particular, it was observed that KNbO3, as a result of its high surface area and the suitable band gap, showed the highest CH4 generation, (86.842 ppm g−1 h−1). Some of the tested photocatalysts could generate H2 and O2 at a very promising rate; Sr4Nb2O9 and NaNbO3 were the best two photocatalysts, with an average O2 production rate of 69.476 ppm g−1 h−1 and 57.928 ppm g−1 h−1, respectively. Further, NaNbO3 showed the highest H2 production average with a rate of 220.128 ppm g−1 h−1. The photocatalysts presented herein represent a significant improvement because of the reactor type and the preparation techniques implemented in this study. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this work, a simple procedure of melamine determination in dairy products is reported. This is based first on melamine extraction from dairy products by 1% acetic acid, sonication, centrifugation and filtration by 0.45 µm filter. The proposed method has a low detection limit (0.50 mg kg−1), high accuracy (%recovery 98.9%), high precision (%RSD range 1.6-2.5%), high calibration sensitivity (19,335 (mg l−1)−1), and a wide dynamic range (1.0-50.0 mg l−1). Melamine was accurately quantified in spiked powdered milk, infant powder milk, full-fat liquid milk, fat-free liquid milk, local yoghurt, and local soft cheese (spiking levels 0.5, 50, and 1000 mg kg−1). The samples have variable amounts of fat (0-29%) and protein (3-23%) indicating the wide applicability of the proposed method. The %recoveries with %RSD were 78.2-103.6(2.5), 92.7-98.8(4.7), 79.3-101.5(3.8), 86.3-101.0(2.6), 78.0-89.2 (8.3), and 91.8-103.8(3.2) for soft cheese, yoghurt, powdered milk, infant powder, full-fat liquid milk, fat-free liquid milk, respectively. Practical Applications A simple and accurate analytical method was proposed for quick melamine detection and quantification in milk and dairy products having variable amounts of fat (0-29%) and protein (3-23%) with minimal sample clean up. The method is mainly based on melamine extraction by 1% acetic acid, sonication, centrifugation for 4.0 min, and filtration by 0.45 μm cellulose filter. The method could detect melamine down to 0.50 mg kg−1 with acceptable accuracy and precision (2.5 mg kg−1 is the upper limit of melamine in milk and dairy products). The proposed method was found effective for melamine quantification at three variable spiked levels (0.5, 10, and 1000 mg kg−1) in local soft cheese, local yoghurt, powdered milk, infant powder, full-fat liquid milk, fat-free liquid milk with %recoveries (%RSD) of 78.2-103.6 (2.5), 92.7-98.8 (4.7), 79.3-101.5 (3.8), 86.3-101.0 (2.6), 78.0-89.2 (8.3), and 91.8-103.8(3.2), respectively. [ABSTRACT FROM AUTHOR]