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The implementation of mixed matrix membranes (MMMs) for sub-angstrom scale gas separations remains a grand challenge. Herein, a series of analogous mixed matrix membrane (AMMMs) were constructed via molecular-level hybridization by utilizing a reactive ionic liquid (RIL) as the continuous phase and graphene quantum dots (GQD) as nanofiller for sub-angstrom scale ethylene/ethane (0.416 nm/0.443 nm) separation. With a small number of GQDs (3.5 wt%) embedded in GQD/RIL AMMMs, ethylene permeability soared by 3.1-fold, and ethylene/ethane selectivity simultaneously boosted by nearly 60 % and reached up to 99.5, which outperformed most previously reported state-of-the-art membranes. Importantly, the interfacial pathway structure was visualized and their self-assembly mechanism was revealed, where the non-covalent interactions between RIL and GQDs induced the local arrangement of IL chains to self-assemble into plenty of compact and superfast interfacial pathways, contributing to the combination of superhigh permeability and selectivity.

A series of iron-based perovskite oxides BaFe1−xCuxO3−δ (x = 0.10, 0.15, 0.20 and 0.25, abbreviated as BFC-10, BFC-15, BFC-20 and BFC-25, respectively) as cathode materials have been prepared via a combined EDTA-citrate complexing sol-gel method. The effects of Cu contents on the crystal structure, chemical stability, electrical conductivity, thermal expansion coefficient (TEC) and electrochemical properties of BFC-x materials have been studied. All the BFC-x samples exhibit the cubic phase with a space group Pm3m (221). The electrical conductivity decreases with increasing Cu content. The maximum electrical conductivity is 60.9 ± 0.9 S cm−1 for BFC-20 at 600 °C. Substitution of Fe by Cu increases the thermal expansion coefficient. The average TEC increases from 20.6 × 10−6 K−1 for BFC-10 to 23.7 × 10−6 K−1 for BFC-25 at the temperature range of 30–850 °C. Among the samples, BFC-20 shows the best electrochemical performance. The area specific resistance (ASR) of BFC-20 on SDC electrolyte is 0.014 Ω cm2 at 800 °C. The single fuel cell with the configguration of BFC-20/SDC/NiO-SDC delivers the highest power density of 0.57 W cm−2 at 800 °C. The favorable electrochemical activities can be attributed to the cubic lattice structure and the high oxygen vacancy concentration caused by Cu doping.

MicroRNA (miRNA) play a pivotal role in the development of liver fibrosis. However, the functions of miRNA in hepatitis C virus (HCV)-related liver fibrosis remain unclear. In this study, we systematically analyzed the microarray data of the serum miRNA in patients with HCV-induced hepatic fibrosis. Among 41 dysregulated miRNA, miR-1273g-3p was the most significantly upregulated miRNA and correlated with the stage of liver fibrosis. Overexpression of miR-1273g-3p could inhibit translation of PTEN, increase the expression of α-SMA, Col1A1, and reduce apoptosis in HSCs. Hence, we conclude that miR-1273g-3p might affect the activation and apoptosis of HSCs by directly targeting PTEN in HCV-related liver fibrosis.

Poly(l-lactic acid) (PLLA) composite membranes were fabricated by nonsolvent induced phase separation method using polyaniline (PANI) as an additive. Membrane structure was characterized by attenuated total reflectance Fourier transform-infrared spectroscopy, X-ray diffraction, scanning electron microscopy, porosity, and pore size analysis. Membrane performance was assessed by goniometer, pure water flux, molecular weight cut-off, static adsorption and dynamic filtration. The incorporation of PANI significantly improved the hydrophilicity and permeability of PLLA composite membrane, and eventually enhanced the antifouling performance of composite membrane compared with pure PLLA membrane. It was demonstrated that PLLA composite membrane with 1 wt % PANI had better separation and antifouling performance compared with other composite membranes. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44452.

Poly(l-lactide) (PLLA)/TiO2 composite membranes were fabricated by immersion precipitation method. The resulting membranes were characterized using various methods including XRD, ATR-FTIR, TGA, DSC, SEM, goniometer, and molecular weight cut-off. The antifouling performance of the membrane was investigated through the filtration experiments of the oil/water emulsion. XRD, SEM, and ATR-FTIR results indicated that TiO2 was successfully introduced into the membrane, while DSC and TGA indicated the enhancement of thermal stability of membrane. The improvement of membrane hydrophilicity was confirmed by goniometer. In addition, the pore size and porosity on the membrane surface varied obviously with increasing the TiO2 loading. It was concluded that PLLA/TiO2 composite membranes had better antifouling and recycling performance compared with the pure PLLA membrane. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43542.

Differential scanning calorimetry (DSC) was used to examine the miscibility of polystyrene (PS), mol. wt. 105, with a phase-separated styrene-dimethylsiloxane (S-DMS) diblock copolymer, Mn = 3800, 86 wt% S. Mixtures whose S content varied from 4 to 96 wt% PS were examined at a 10 K min−1 heating rate following a 200 K min−1 cooling rate from temperatures varying from 403 to 573 K. At some compositions, two glass transition temperatures, Tgs, corresponding to PS transitions were observed; at others only a single Tg was observed. When it was assumed that the 200 K min−1 cooling rate corresponded to quenching from the starting temperature, and when the heat capacity changes at the S glass transitions were used to calculate the percentage of S repeat units undergoing each glass transition, it was possible to calculate an approximate partial phase diagram for this mixture. At 96 wt% PS, there was evidence for a small amount of mixed S phase, possibly block copolymer micelles, in equilibrium with PS; from about 60 to 90 wt% PS, the S repeat units from the block copolymer appeared to be completely mixed with the PS. At lower wt% PS, unmixed block copolymer was in equilibrium with block copolymer whose S segments were mixed with the PS. The phase diagram appeared to vary only slightly with temperature.