A new seeding method, namely, varying-temperature hot-dip coating (VTHDC), is proposed for synthesis of zeolite T membranes by secondary hydrothermal growth. The VTHDC method is composed of hot-dip coating at higher temperature, rubbing off the superfluous crystals, and hot-dip coating at lower temperature. It was found that the method was flexible and effective for combined control over the seed suspension concentration, seed size, and coating temperature, leading to combined control of properties of the seed layer over the seed size, thickness, coverage, and defect. A thin continuous, smooth defect-free asymmetric seed layer was achieved consisting of large and small zeolite T seed crystals. The resulting zeolite T membrane M5 exhibited high pervaporation performance with the flux reaching 2.12 and 2.52 kg/m 2 h for the dehydration of 90 wt % EtOH/H 2 O and IPA/H 2 O mixture, respectively, at 348 K. The corresponding separation factor was up to 1301 and 10,000, respectively. V V C 2012 American Institute of Chemical Engineers AIChE J, 59: 936-947, 2013

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Air pollution and public health incidents have become a serious global concern. Hierarchical nanofibrous membranes are taken as high-performance filters with advanced structure, but the reliable fabrication is still challenging....

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The hexagonal boron nitride (h-BN) nanosheets have been used as nanofillers to improve the barrier properties of the waterborne epoxy (WEP) coatings. However, the h-BN nanosheets tend to agglomerate, which limits their anticorrosion applications. In this paper, the h-BN/polyaniline (h-BN/PANI) nanocomposites were prepared by the in situ polymerization of aniline on the surfaces of the h-BN nanosheets, which were further used to improve the anticorrosion performance of the WEP coatings. The structures of the as-prepared h-BN/PANI nanocomposites were investigated by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray photoelectron spectroscopy. The anticorrosion performances of the coatings were evaluated by electrochemical impedance spectroscopy. After immersion in 3.5 wt % NaCl solution for 28 days, the macro-morphologies and elemental changes of the substrate surfaces were analyzed by a 3D digital microscope and an energy-dispersive spectroscope, respectively. The results showed that the WEP coatings with the h-BN/PANI nanocomposites, especially that with 2 wt % h-BN/PANI nanocomposites, exhibited remarkably reinforced anticorrosion performance compared to the pure WEP coating. For the WEP coating, the coating with 1 wt % PANI, and the coating with 1 wt % h-BN, the substrates have been completely corroded. However, there was no obvious corrosion region for the coating containing 2 wt % h-BN/PANI nanocomposites. The superior anticorrosion performance of the coatings with h-BN/PANI nanocomposites was mainly attributed to the synergistic effect of the well-dispersed h-BN/PANI nanocomposites as the physical barrier and PANI as the corrosion inhibitor in this system.

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Phenylketonuria (PKU) is an inborn error of phenylalanine metabolism primarily treated through a phenylalanine-restrictive diet that is frequently supplemented with an amino acid formula to maintain proper nutrition. Little is known of the effects of these dietary interventions on the gut microbiome of PKU patients, particularly in adults. In this study, we sequenced the V4 region of the 16S rRNA gene from stool samples collected from adults with PKU (n = 11) and non-PKU controls (n = 21). Gut bacterial communities were characterized through measurements of diversity and taxa abundance. Additionally, metabolic imputation was performed based on detected bacteria. Gut community diversity was lower in PKU individuals, though this effect was only statistically suggestive. A total of 65 genera across 5 phyla were statistically differentially abundant between PKU and control samples (p < 0.001). Additionally, we identified six metabolic pathways that differed between groups (p < 0.05), with four enriched in PKU samples and two in controls. While the child PKU gut microbiome has been previously investigated, this is the first study to explore the gut microbiome of adult PKU patients. We find that microbial diversity in PKU children differs from PKU adults and highlights the need for further studies to understand the effects of dietary restrictions.

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