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High performance dual-layer hollow fiber membranes have been developed for ethanol dehydration by incorporating a tiny amount (i.e., less than 0.3 wt%) of UiO-66-NH 2 particles into cellulose triacetate (CTA)/Ultem® hollow fibers fabricated by the immiscibility induced phase separation (I2PS) process. Effects of particle loading, air gap, feed temperature, feed composition and heat treatment on membrane performance for ethanol dehydration were systematically studied. Positron annihilation spectroscopy (PAS) analyses were conducted to disclose the mechanisms of performance enhancement. Adding UiO-66-NH 2 particles improves the permeation flux due to the reduced transport resistance and the enhanced affinity between water and the membranes. The hollow fiber (O-0.2-1.5) consisting of 0.2 wt% UiO-66-NH 2 particles in the outer layer possesses the most outstanding separation performance among the newly developed hollow fibers. It has an ultra-high flux of 2667g/m2h (i.e., water permeance of 20.05 mol/m2h kPa) and its permeate comprises 95.00 wt% water, equivalent to a mole-based selectivity of 152 at 50 °C with a feed comprising 85 wt% water and 15 wt% ethanol. After annealing at 120 °C for 2h, the flux drops to 1977 g/m2h but the water concentration in permeate jumps to 98.07 wt%. A comparison with literature data verifies the excellent performance of the newly developed I2PS membranes. The membranes also show impressively stable performance throughout the 200h monitored period for ethanol dehydration. The newly developed membranes may have great potential for pervaporation dehydration of ethanol for industrial applications. Image 1 • UiO-66-NH 2 incorporated I2PS hollow fibers have been developed. • Adding a tiny amount of UiO-66-NH 2 effectively improves flux. • Heat treatment greatly enhances separation factor. • The fibers show superior ethanol dehydration performance. • The fibers have excellent long term stability. [ABSTRACT FROM AUTHOR]

Drug resistance is a big problem in cancer treatment and one of the most prominent mechanisms underlain is overexpression of ATP-binding cassette (ABC) transporters, particularly ABCB1, ABCC1 and ABCG2. Inhibition of ABC transporters is an important approach to overcome drug resistance. The inositol-requiring enzyme 1α (IRE1α), an arm of unfolded protein response (UPR), splices XBP1 mRNA to generate an active transcription factor XBP1s. UPR is implicated in drug resistance. However, the underlying mechanism is unclear. We found that the anticancer drugs such as 5-fluorouracil (5-FU) activated the IRE1α-XBP1 pathway to induce the expression of ABCB1, ABCC1 and ABCG2 in colon cancer cells. Inhibition of IRE1α RNase activity with small molecule 4μ8c suppressed the drug-induced expression of these ABC transporters and sensitized 5-FU-resistant colon cancer cells to drug treatment. In vivo xenograft assay indicates that administration of 4μ8C substantially enhanced the efficacy of 5-FU chemotherapy on 5-FU-resistant colon cancer cells. These results suggest that IRE1α-targeting might be a strategy to cope with drug resistance of colon cancer. [ABSTRACT FROM AUTHOR]

• The TEMs particles displays high expansion performance on PET fabric. • The PET@TEMs/APP composite fabric possesses low thermal conductivity and displays high thermal insulation performance. • The PET@TEMs/APP composite fabric displays high flame retardancy. • The PET@TEMs/APP composite fabric is promising to serve as soft and safety thermal insulation material for energy saving. The development of thermally resistant textiles with fire safety using thermo-expandable hollow microsphere (TEHM) has garnered significant interest. In this study, TEHM and ammonium polyphosphate (APP) were bonded to polyester fabric surface by using polyurethane coating. The surface morphology, thermally resistant, flame-retardant performance and mechanism of the developed PET@TEHM/APP composite fabric were investigated. The PET@TEHM/APP composite fabric exhibited the reduced thermal conductivity of 0.07458 W/m·K from 0.13120 W/m·K of pristine PET fabric. The thermal conduction and radiation performance of the PET@TEHM/APP composite fabric decreased owing to the low thermal conductivity of the expanded TEHM. The PET@TEHM/APP composite fabric presented a damaged length of 13.5 cm without melt dripping, achieving the B 1 classification. The peak heat release of the PET@TEHM/APP composite fabric decreased by 58.3 % versus pristine PET fabric according to cone calorimetry test. PET@TEHM/APP composite fabric also had an FRI of 1.001, showing 'Good' flame retardancy performance. TG-IR and char residue analyses suggested that the flame retardancy of PET@TEHM/APP composite fabric improved by the synergic flame-retardant action in both gas and condensed phases. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The modified Z-scan technique using the quasi-one-dimensional slit (QODS) beam for characterizing the third-order optical nonlinearity has been reported recently. In the present work, we investigate the effect of the finite length of the slit in the QODS beam Z-scan for the practical experimental conditions, and then give an empirical expression that allows the direct estimation of nonlinear refraction coefficient from the measured normalized peak-valley transmittance difference. In particular, we explore relatively in detail the influences of the sample imperfection on the Z-scan traces, such as the hollow hole of the sample and the nonuniform nonlinearity. Compared with the other Z-scan techniques, such as the top-hat and Gaussian-beam Z-scans, we find that the QODS beam Z-scan has the great improvement for the sample imperfections. The results suggest that the QODS beam Z-scan is a more promising and useful technique for characterizing the optical nonlinearity of an imperfect sample. [Copyright &y& Elsevier]

Abstract Sb 2 Se 3 based thin film solar cells have recently drawn a growing research interest. In the work, Sb 2 Se 3 thin films were deposited on BK7 glass substrates by thermal evaporation at room-temperature. The Sb 2 Se 3 powder was prepared by mechanical alloying method. It can found that the prepared Sb 2 Se 3 powder has single Sb 2 Se 3 crystal structure with slight Sb-excess. The influence of the evaporation current on the micro-structure of the films was investigated. The results show that the thin films have the similar contents as the Sb 2 Se 3 powder, but have amorphous structure. After annealing, the crystallinity of the Sb 2 Se 3 thin films has single Sb 2 Se 3 phase with well-crystallized and smooth surface. The optical band gap of Sb 2 Se 3 thin films deposited at 120 A is 1.26 eV, indicating that the thin film has good optical property. Highlights • Sb 2 Se 3 thin films were deposited by thermal evaporation using Sb 2 Se 3 powder prepared by mechanical alloying method. • The heat treatment and evaporation current were changed to improve the micro-structure and property of Sb 2 Se 3 thin films. • The preferred growth orientations of Sb 2 Se 3 thin film have dependence with the evaporation currents. [ABSTRACT FROM AUTHOR]

Abstract: This study is one of the first to test the relationship of formulation and structure of reconstituted high density lipoproteins (rHDL), drug behavior involved in remolding process and their targeting mechanism in a foam cell model. Tanshinone IIA-loaded rHDL (TA-rHDL) with different formulations and techniques were prepared and characterized. The targeting mechanism and drug behavior involved in remolding process were undertaken using a foam cell model. TA-rHDL prepared with cholesteryl ester (CE) and glycerol trioleate (TG) were spheres, or else discs. Guanidine hydrochloride denaturation experiments showed increased stability with TA-rHDL, compared to free apos. Phagocytosis tests demonstrated that the spherical TA-rHDL had targeting effect for foam cells through the scavenger receptor-BI and CE-TG interchange with TG-rich lipoproteins pathway under cholesteryl ester transfer protein. Discoidal TA-rHDL could reconstruct to spheres and target via a similar route as TA-rHDL spheres, showing a higher targeting efficiency. Lipophilic Tanshinone IIA could be re-entrapped in rHDL after remolding from discs to spheres and uptaken more by foam cells. Discoidal rHDL may serve as potential nanocarriers for targeting lipophilic cardiovascular drugs to atherosclerosis plaque. [Copyright &y& Elsevier]