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In the field of perovskite optoelectronics, developing hole-transporting materials (HTMs) on the spiro[fluorene-9,9′-xanthene] (SFX) platform is one of the current research focuses. The SFX inherits the merits of spirobifluorene in terms of the configuration and property, but it is more easily derivatized and regulated by virtue of its binary structure. In this work, we design and synthesize four isomeric SFX-based HTMs, namely m-SFX-mF, p-SFX-mF, m-SFX-oF, and p-SFX-oF, through varying the positions of fluorination on the peripheral aniline units and their substitutions on the SFX core, and the optoelectronic performance of the resulting HTMs is evaluated in both perovskite solar cells (PSCs) and light-emitting diodes (PeLEDs) by the vacuum thermal evaporating hole-transporting layers (HTLs). The HTM p-SFX-oF exhibits an improved power conversion efficiency of 15.21% in an inverted PSC using CH3NH3PbI3 as an absorber, benefiting from the deep HOMO level and good HTL/perovskite interface contact. Meanwhile, the HTM m-SFX-mF provides a maximum external quantum efficiency of 3.15% in CsPb(Br/Cl)3-based PeLEDs, which is attributed to its perched HOMO level and shrunken band-gap for facilitating charge carrier injection and then exciton combination. Through elucidating the synergistic position effect of fluorination on aniline units and their substitutions on the SFX core, this work lays the foundation for developing low-cost and efficient HTMs in the future. [ABSTRACT FROM AUTHOR]

Ni x S y /NiSe 2 hybrid nanoparticle film grown in situ on F-doped SnO 2 (FTO) glass is synthesized by a gentle solvothermal method and used as efficient counter electrode for dye-sensitized solar cells (DSSCs). The two-step strategy involving sulfuration and subsequent selenization reaction using nickel hydroxide as the precursor can effectively avoid the film cracking and detaching thus to obtain a uniform hybrid nanoparticle film with rich catalytic active sites and good electron transport ability. The electrocatalytic activity of hybrid catalyst compared with single NiSe 2 and Ni x S y is investigated in detail by cyclic voltammetry (CV), electrochemical impedance spectra (EIS) and Tafel polarization measurements. Due to the synergistic effect of different components, the hybrid Ni x S y /NiSe 2 exhibits higher electrocatalytic performance for I 3 − reduction. As a result, the DSSCs with Ni x S y /NiSe 2 hybrid electrode shows an impressive higher short circuit photocurrent and power conversion efficiency (8.64%) than that with Ni x S y (7.95%) and NiSe 2 (7.47%) counter electrodes, just a little bit inferior to Pt (9.01%), which indicates that this new kind of material can work as a promising alternative low-cost catalyst for DSSCs or other electrocatalytic applications. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies have shown that the SUP genes play important roles in flower development and plant growth and morphogenesis. In this study, we isolated and characterized a SUPERMAN-like gene DgSZFP from chrysanthemum. DgSZFP contains one conserved Cys2/His2-type zinc finger motifs in the N-terminal region and an EAR-box in C-terminus. Its expression was significantly higher in nodes, flower buds, disc stamens, and petals than in the other tissues. Overexpression of DgSZFP in tobacco resulted in enhanced branching, reduced plant height, increased the width of petal tubes, produced the staminoid petals and petaloid stamens in flowers, and enhanced the seed weight and size. In addition, DgSZFP-overexpression tobacco plants accumulated high concentrations of cytokinin and chlorophyll. These results suggest that DgSZFP may be the candidate gene for regulating branching and floral organ development in chrysanthemum. [Copyright &y& Elsevier]

Plant-specific WRKY transcription factors (TFs) are involved in stress responses such as cold, high salinity, or drought as well as abscisic acid (ABA) signaling. However, their roles in abiotic stresses are still not well known in chrysanthemum. Here, we isolated a novel WRKY gene, DgWRKY1, from chrysanthemum ( Dendranthema grandiflorum). DgWRKY1 contains one WRKY domain and one CH zinc-finger motif ( C-X- C-X- H-X- H), and was localized in the nucleus. Expression of DgWRKY1 was up-regulated by drought, salinity, and ABA. The DgWRKY1-overexpression tobacco plants were more tolerant to salt, and seed gerrmination was more sensitive to ABA, than the wild-type (WT). The transgenic lines exhibited less accumulation of hydrogen peroxide (HO) and malondialdehyde (MDA) under salt stress, and less antioxidant enzyme activity, including peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), than the WT under both control conditions and salt stress. In addition, there was greater up-regulation of the ROS-related enzyme genes ( NtSOD, NtPOD, and NtCAT) in transgenic lines under normal or salt conditions. These findings suggest that DgWRKY1 plays a positive regulatory role in salt stress response. [ABSTRACT FROM AUTHOR]

Plant vacuolar Na+/H+ antiporter genes play significant roles in salt tolerance. However, the roles of the chrysanthemum vacuolar Na+/H+ antiporter genes in salt stress response remain obscure. In this study, we isolated and characterized a novel vacuolar Na+/H+ antiporter gene DgNHX1 from chrysanthemum. The DgNHX1 sequence contained 1920 bp with a complete open reading frame of 1533 bp encoding a putative protein of 510 amino acids with a predicted protein molecular weight of 56.3 kDa. DgNHX1 was predicted containing nine transmembrane domains. Its expression in the chrysanthemum was up-regulated by salt stress, but not by abscisic acid (ABA). To assess roles of DgNHX1 in plant salt stress responses, we performed gain-of-function experiment. The DgNHX1-overexpression tobacco plants showed significant salt tolerance than the wild type (WT). The transgenic lines exhibited more accumulation of Na+ and K+ under salt stress. These findings suggest that DgNHX1 plays a positive regulatory role in salt stress response. [ABSTRACT FROM AUTHOR]

Abstract: WRKY transcription factor genes (TFs) play important roles in response to various abiotic stresses. However, the roles of the chrysanthemum WRKY genes in abiotic stress response remain obscure. In this study, we functionally characterized a novel WRKY gene, DgWRKY3, from chrysanthemum (Dendranthema grandiflorum). Its expression in the chrysanthemum was up-regulated by salinity or dehydration stress, but not by abscisic acid (ABA). The DgWRKY3-overexpression tobacco plants increase salt tolerance compared with wild-type (WT) tobacco plants. The increased levels of proline were observed in transgenic plants compared to WT plants under salt stress. In addition, the DgWRKY3 transgenic plants reduced accumulation of malondialdehyde (MDA) and hydrogen peroxide (H2O2) compared with WT plants, accompanied by higher activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) and the greater accumulation of antioxidants including ascorbate (AsA) and glutathione (GSH) under salt stress. Moreover, the DgWRKY3 transgenic plants enhanced the expression of stress-related genes involved in osmotic adjustment and membrane protection (NtP5CS, NtLEA5, and NtERD10D) and oxidative stress response (NtSOD, NtPOD, NtCAT, and NtAPX) under salt stress. However, no significant difference in the expression of stress-related genes (NtP5CS, NtLEA5, NtERD10D, NtSOD, NtPOD, NtCAT, and NtAPX) was found between the DgWRKY3-overexpression and WT tobacco plants under normal conditions, despite the fact that the constitutive promoter was used to drive DgWRKY3. These findings suggest that DgWRKY3 functions as a positive regulator to mediate tolerance of plants to salt stress. [Copyright &y& Elsevier]

ABSTRACT One-pot synthesis of thermoresponsive magnetic composite microspheres with a poly( N-isopropylacrylamide) (PNIPAM) shell and a Fe3O4 core is demonstrated. Temperature sensitivity of PNIPAM was adopted to design the novel synthesis pathway. The as-prepared composite microspheres have an obvious core-shell structure with a mean size of approximately 250 nm. The Fe3O4 core is approximately 5 nm and the thickness of the PNIPAM shell is approximately 10 nm. The content of Fe3O4 in the composite microspheres can be controlled by this method. The composite microspheres experience a swelling and shrinking process in water by adjusting the temperature below and above the lower critical solution temperature (LCST) around 32 °C. These microspheres also show fine response to an external magnetic field. This work presents a platform to synthesize organic/inorganic composite microspheres in a facile and efficient approach. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2702-2708 [ABSTRACT FROM AUTHOR]

Abstract: This work presents a new approach for the synthesis of multiresponsive composite microspheres of PNIPAM/chitosan. The resulting microspheres in a sandwich structure with PNIPAM nanoparticles embedded in the crosslinked chitosan matrix were characterized. Compared to other preparation methods, this proposed technique not only is a facile route but also endows the microspheres a desirable structure. The products undergo a temperature induced volume phase transition and exhibit an appreciable pH response. They are further tested as drug carriers to investigate potential application. The encapsulation efficiency in acidic environment (pH=4.0) is 73.5% and much higher than that in neutral (20.3%, pH=6.9) and alkaline (15.1%, pH=9.2) environments. The release of the drug from the microspheres can be controlled by pH and temperature. [Copyright &y& Elsevier]

Abstract: A novel porous composite membrane adsorbent GA-HA/SA was prepared by glutaraldehyde (GA) crosslinked humic acid (HA) immobilized sodium alginate (SA) and used to remove Cu(II) ions from wastewater. Compared with traditional centrifugation or filtration methods for separating adsorbent from solution, the Cu-HA/SA can be used more conveniently. The physico-chemical properties of GA-HA/SA before and after adsorption were investigated by FT-IR, SEM and EDX methods. To investigate the effects of experimental parameters on adsorption behavior, a batch of experiments were performed by changing the concentration of porogen polyethylene glycol in the GA-HA/SA, solution pH, ionic strength, initial Cu(II) ions concentration and contact time. The GA-HA/SA showed the maximum uptake of 63.1mg/g under the optimal adsorption condition. Based on adsorption experiment, it can be found that uptake capacity of the GA-HA/SA for Cu(II) ions decreased with an increasing of ionic strength, and solution pH decreased until the adsorption equilibrium. Kinetics experiments indicated the pseudo-second-order model displayed the best correlation with adsorption kinetics data. The Crank model showed that the intraparticle solute diffusion is the rate-controlling adsorption step. Besides, adsorption experimental data could be better described by the Freundlich isotherm model. [Copyright &y& Elsevier]

Abstract: Composites of poly (N-isopropylacrylamide-co-acrylic acid)/titanium dioxide (TiO2) have been prepared via UV-initiated free radical polymerization. Fourier transform infrared spectra (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), environmental scanning electron microscope (ESEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) are used to study the composition, structure, and morphology of the as-prepared composites. TiO2 is found to be successfully encapsulated in the copolymer in spherical shapes with size of 2.5μm. The thermo- and pH-responsive properties of the composites are observed using dynamic light scattering (DLS). The photocatalytic property of the composites is studied using UV–vis spectrophotometer on the degradation of methyl orange (MO) solution under various pHs and temperatures. Degradation ratio is higher at low pH and increases with increasing temperature above volume phase transition temperature (VPTT). [Copyright &y& Elsevier]

Abstract: The surfaces of poly(vinyl alcohol) (PVA) membranes are treated using γ-aminopropyl triethoxysilane (APTEOS) to prepare PVA/APTEOS hybrid membranes. The as-prepared membranes are characterized by wide-angle X-ray diffraction (WXRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), contact angle meter and X-ray photoelectron (XPS). The performance of the membranes is investigated for pervaporation separation of ethanol/water (85/15) mixtures. The effect of surface treating time and feed temperature is studied. The surface-treated membranes exhibit good water permselectivity. The separation factor increases with increasing the APTEOS content, and first increases with increasing treating time below 120min then slightly decreases afterwards. However, the separation factor is found to demonstrate a unique temperature dependence in a range 50–70°C. [Copyright &y& Elsevier]

Abstract: A novel anion exchange membrane has been prepared using polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SEBS) as a starting material. Chloromethyl groups are first introduced into the SEBS and then converted into the quaternary ammonium groups. The membrane is characterized by Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA). Water uptake, oxidative resistance, ionic conductivity and methanol permeability are measured to evaluate its performance in a direct methanol alkaline fuel cell. The ionic conductivity and permeability of the membrane to methanol was found to increase with temperature. The membrane exhibits an ionic conductivity of 9.37×10−3 Scm−1 in deionized water at 80°C. For aqueous methanol solutions between 2 and 10M at 30°C, the methanol permeability was observed to range 2.34–4.45×10−7 cm2 s−1. Our novel SEBS membrane also shows high oxidative resistance to Fenton''s reagent and good thermal stability under an air atmosphere. [Copyright &y& Elsevier]

Abstract: Molecular simulation techniques have been adopted for the first time for understanding the structure–property relationships of three highly fluorinated polyamide–imide (PAI) isomers (6FDA/8p, 6FDA/8m and 6FDA/12p). The PAIs being considered in this work are based on 2,2-bis(3,4-decarboxy-phenyl) hexafluoropropane dianhydride (6FDA) and N,N-bis(amino-phenyl)-perfluoroalkane-α,ω-dicarboxamide diamines. The density, fractional free volume (FFV) and glass transition temperature (T g) of the PAIs are calculated to investigate the microstructure of the PAIs and the structural dependence of sorption and diffusion properties of CO2/CH4 pair. The 6FDA/8p and 6FDA/12p give both higher permeability and permselectivity than the 6FDA/8m because the rigid para-isomer functions as a molecular sieve. With a longer length of oligo(tetrafluoroethene) segment, the 6FDA/12p has permeability and selectivity greater than 6FDA/8p. Hence, this study may provide a guideline for designing PAI membranes to have desirable properties of permeability and permselectivity. [Copyright &y& Elsevier]

Abstract: Poly(methyl methacrylate) (PMMA) composites containing polyhedral oligomeric silsesquioxanes substituted with isobutyl (iBuPOSS) are studied by molecular dynamics simulation. Properties of the composites, mixing thermodynamics and diffusion behaviors of O2 and N2 were investigated. Introduction of abundant iBuPOSS remarkably enhances the mobility of PMMA chain, whose self-diffusion coefficient in the composites with 51.14wt% iBuPOSS is five times greater than that in pristine PMMA. Below 15wt% loading iBuPOSS molecules homogeneously disperse in the PMMA matrix, whereas above 20wt% loading iBuPOSS molecules aggregate into crystallites, and iBuPOSS molecules have restricted motion in the composites. Cohesive energy density and solubility parameter increase with increasing the iBuPOSS loading. Through-pores that are the channels for gas diffusion are observed in the composites with higher iBuPOSS loading. The incorporation of iBuPOSS leads to an increase in the diffusivities of O2 and N2 in the composites at low iBuPOSS loading (≤15wt%), and the composites with 15wt% iBuPOSS have the highest diffusion coefficient of O2 and N2. [Copyright &y& Elsevier]

Abstract: Quaternized cardo polyetherketone (QPEK-C) membranes for alkaline fuel cells were prepared via chloromethylation, quaternization and alkalization of cardo polyetherketone (PEK-C). The chemical reaction for PEK-C modification was confirmed by nuclear magnetic resonance (1H NMR) and energy-dispersive X-ray spectroscopy (EDAX). The QPEK-C membrane was characterized by X-ray photoelectron spectroscopy (XPS) and thermo gravimetric analysis (TG). The ion-exchange content (IEC), water and methanol uptakes, methanol permeability and conductivity of the QPEK-C membranes were measured to evaluate their applicability in alkaline methanol fuel cells. The ionic conductivity of the QPEK-C membrane varied from (1.6 to 5.1)×10−3 Scm−2 over the temperature range 20–60°C. The QPEK-C membrane showed excellent methanol resistance. When the concentration of methanol was 4M, the methanol permeability was less than 10−9 cm2 s−1 at 30°C. [Copyright &y& Elsevier]

Abstract: Quaternized poly(vinyl alcohol) (q-PVA) was synthesized, and crosslinked by glutaraldehyde to reduce the swelling of the q-PVA in an aqueous solution. The structure of the q-PVA and its crosslinked membranes was characterized by scanning electron microscopy, X-ray powder diffraction, and water contact angle measurements. Pervaporation performance of the membranes was studied by the dehydration of 85wt% ethanol solution at 50°C. The introduction of quaternary ammonium groups enhanced the hydrophilicity and water permselectivity. The water permeability and permselectivity of the q-PVA membranes increased simultaneously with increasing degree of quaternization (DQ). The crosslinking caused a decrease in swelling and an increase in water permselectivity of the q-PVA membranes. The q-PVA membrane with DQ of 4.035% has a highest water permeability of 12.628gμmm−2 h−1 kPa−1, and the crosslinked q-PVA membrane with degree of crosslinking of 3.92% has a highest water permselectivity of 75. [Copyright &y& Elsevier]

Abstract: In this paper, chitosan (CS)/poly (vinyl pyrrolidone) (PVP) blend membranes crosslinked by glutaraldehyde (GA) were prepared for the separation of ethyl acetate/ethanol/water azeotrope by pervaporation (PV). Their chemical and physical characteristics were studied by Fourier transform infrared (FTIR), environmental scanning electron microscopy (ESEM), X-ray diffraction (XRD), differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), and contact angle measurement. The PV properties of the membranes were investigated through dehydration of the azeotrope. Permeation flux increased with increasing feed temperature and PVP content, while separation factor decreased. However, the separation factor increased with increasing GA content, whereas the flux decreased. The results showed that the membranes with PVP content of 10wt% exhibited excellent PV properties with a flux of 953gm−2 h−1 and separation factor of 746 at 35°C. [Copyright &y& Elsevier]

Abstract: Molecular dynamics (MD) simulation was used to study the swelling properties of poly(vinyl alcohol) (PVA) in ethanol solutions containing 15, 30 and 45wt% water. The characteristics of the swollen PVA, intrinsic relation between the microstructure of the swollen PVA and the diffusion of water and ethanol in the PVA matrix were analyzed. It was found that the free volume of the swollen PVA reduced with reductions in the degree of crystallinity was accompanied by an increase in the mobility of PVA chains. Water located mostly in the hydrophilic region of the hydroxyl groups of PVA chains; and hydrogen bonding formed between water and PVA. It was also noted water clusters form in the swollen PVA, whose size increased with increasing degree of swelling, whereas ethanol molecules disperse almost individually in the PVA matrix. The diffusion coefficients of water and ethanol in the swollen PVA are predicted to increase linearly with increasing swelling. [Copyright &y& Elsevier]

Abstract: A series of organic–inorganic membranes were prepared through sol–gel reaction of quaternized poly(vinyl alcohol) (QAPVA) with different contents of tetraethoxysilanes (TEOS) for alkaline direct methanol fuel cells. These hybrid membranes are characterized by FTIR, X-ray diffraction (XRD), scanning electron microscopy/energy-dispersive X-ray analysis (SEM/EDXA) and thermo gravimetric analysis (TGA). The ion exchange content (IEC), water content, methanol permeability and conductivity of the hybrid membranes were measured to evaluate their applicability in fuel cells. It was found that the addition of silica enhanced the thermal stability and reduced the methanol permeability of the hybrid membranes. The hybrid membrane M-5, for which the silica content was 5wt%, showed the lowest methanol permeability and the highest ion conductivity among the three hybrid membranes. The ratio of conductivity to methanol permeability of the membrane M-5 indicated that it had a high potential for alkaline direct methanol fuel cell applications. [Copyright &y& Elsevier]

Abstract: Cardo polyetherketone (PEK-C) composite membranes were prepared by casting glutaraldehyde (GA) cross-linked sulfonated cardo polyetherketone (SPEK-C) or silicotungstic acid (STA) filled SPEK-C and poly(vinyl alcohol) (PVA) blending onto a PEK-C substrate. The compatibility between the active layer and PEK-C substrate is improved by immersing the PEK-C substrate in a GA cross-linked sodium alginate (NaAlg) solution and using water–dimethyl sulfoxide (DMSO) as a co-solvent for preparing the STA-PVA-SPEK-C/GA active layer. The pervaporation (PV) dehydration of acetic acid shows that permeation flux decreased and separation factor increased with increasing GA content in the homogeneous membranes. The permeation flux achieved a minimum and the separation factor a maximum when the GA content increased to a certain amount. Thereafter the permeation flux increased and the separation factor decreased with further increasing the GA content. The PV performance of the composite membranes is superior to that of the homogeneous membranes when the feed water content is below 25wt%. The permeation activation energy of the composite membranes is lower than that of the homogeneous membranes in the PV dehydration of 10wt% water in acetic acid. The STA-PVA-SPEK-C-GA/PEK-C composite membrane using water–DMSO as co-solvent has an excellent separation performance with a flux of 592gm−2 h−1 and a separation factor of 91.2 at a feed water content of 10wt% at 50°C. [Copyright &y& Elsevier]

Abstract: Novel cross-linked composite membranes were synthesized to investigate their applicability in anion exchange membrane fuel cells. These membranes consist of quaternized poly(vinyl alcohol) (QAPVA) and quaternized chitosan (2-hydroxypropyltrimethyl ammonium chloride chitosan, HACC) with glutaraldehyde as the cross-linking reagent. The membranes were characterized in term of their water content, ion exchange capacity (IEC), ion conductivity and methanol permeability. FTIR, X-ray diffraction and scanning electron microscopy (SEM) were also used to investigate the relation between the structure and performance of the composite membranes. The composite membranes have a high conductivity (10−3 to 10−2 Scm−1), and a low methanol permeability (from 5.68×10−7 to 4.42×10−6 cm2 s−1) at 30°C. After reviewing all pertinent characteristics of the membranes, we find that the membrane structure is the principal factor affecting the conductivity and methanol permeability of these membranes. [Copyright &y& Elsevier]

Abstract: Sulfonated cardo polyetherketone (SPEK-C) and poly(vinyl alcohol) (PVA) blend membranes were prepared by solution casting method and used in pervaporation (PV) dehydration of acetic acid. The membranes were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and contact angle meter. The results show that thermal crosslinking occurred to the membrane under high temperature annealing. The effective d-spacing (inter-segmental spacing) decreased with PVA content decreasing. The hydrophilicity of the blend membrane increased with SPEK-C content increasing. Swelling and sorption experiments show that the swelling degree of the blend membrane increased, however both the sorption and diffusion selectivities decreased with increasing PVA content. The diffusion selectivity is higher than the sorption selectivity. This suggests that PV dehydration of acetic acid is dominated by the diffusion process. The pervaporation separation index (PSI) of the membrane increases with increasing PVA content and arrives at a maximum when the SPEK-C/PVA ratio is 3/2, then decreases with further addition of PVA. The membrane has an encouraging separation performance with a flux of 492gm−2 h−1 and separation factor of 59.3 at 50°C at the feed water content 10wt%. [Copyright &y& Elsevier]

Abstract: Silicotungstic acid hydrate (STA)/CS hybrid membranes were prepared by filling STA into chitosan (CS) matrix. The membranes were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and contact angle meter. The results show that the hydrophilicity of the hybrid membrane increases, however, the crystallinity of the membrane decreases with STA content increasing. STA was well dispersed in the membrane when its content is less than 8wt%. It is found that the swelling degree of the STA/CS hybrid membrane increases with increasing STA content or methanol (MeOH) content. The effects of STA content, feed MeOH content and feed temperature on pervaporation (PV) performance were also investigated. The results show that separation factor increased with STA content increasing and arrived at a maximum when the STA content is 8wt%, while permeation flux increased with increasing STA content. The separation factor decreased with increasing the feed temperature or MeOH content, however, the flux increased with increasing the feed temperature or MeOH content. The membrane has remarkable separation performance with a flux of 1163gm−2 h−1 and separation factor of 67.3 at 50°C at the feed methanol content 10wt%. [Copyright &y& Elsevier]

Abstract: Novel organic–inorganic hybrid membranes of poly(vinyl alcohol) (PVA)/γ-aminopropyl-triethoxysilane (APTEOS) were prepared through a sol–gel approach in this study. The PVA/APTEOS hybrid membranes were characterized by a wide angle X-ray diffractometer (WXRD), scanning electronic microscope (SEM), themogravimetric analysis (TGA) and a contact angle meter to elucidate the effect of annealing temperature and time on the structure of the hybrid membranes. The swelling of the annealed hybrid membranes in an aqueous ethanol solution was investigated, and permeation performance of the annealed hybrid membranes was studied by pervaporation (PV) of 85wt% ethanol aqueous solution. With annealing temperature or time increasing, both the swelling degree and the permeation flux of the hybrid membranes decreased, while water permselectivity increased. The interaction parameter of water with the membrane χ 13, and ethanol with the membrane χ 23 increased with annealing temperature and time increasing. The relation of the free volume with the permeation properties of the annealed hybrid membranes was studied by positron annihilation lifetime spectroscopy (PALS). And the diffusion behavior of water and ethanol in an aqueous ethanol solution through the hybrid membranes was analyzed by Maxwell–Stefan equation. [Copyright &y& Elsevier]

Abstract: Homogeneous membranes based on sulfonated cardo polyetherketone (SPEK-C) were prepared. The membranes were characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), field emission high resolution transmission electron microscope (HRTEM) and contact angle meter. The results show that both the hydrophilicity and the amorphous region of the membranes increased with sulfonation degree (SD) increasing. The membranes show excellent thermal stability. Sulfonic acid groups exist as a form of ion clusters and distribute in the membranes homogeneously, which form the channel for permeants to pass through. The effects of solvent and SD on the performance of the membranes were studied. The results show that the SPEK-C membrane has excellent performance when the SD is 0.75 and dimethylsulfoxide is used as a solvent. Separation factor decreases and permeation flux increases with the feed temperature and water concentration increasing. The membrane has good separation performance with a flux of 248gm−2 h−1 and separation factor of 103 at 50°C in pervaporation of 90wt% acetic acid in water. [Copyright &y& Elsevier]

Abstract: An improved fully flexible fixed-point charges model for water has been developed to predict the vapor–liquid coexistence properties using the NVT-Gibbs ensemble Monte Carlo technique (GEMC) and the pressure in supercritical region. The average deviation between our simulation and experimental data for saturated liquid densities is 2.75% over temperature range of 314–609K. Comparing with experimental data for T c, P c and ρ c (P c =220.064bar, T c =647.096K and ρ c =0.322g/cm3 for the experimental data), our calculated results (P c =213bar, T c =644.3K and ρ c =0.325g/cm3 for our simulations) are acceptable and are better than those by the SPC-E and TIP4P models. The saturated pressure is calculated by evaluating the pressure of vapor from NPT-MD simulation at the coexistence vapor densities at the nominal temperature. The agreement of our simulated pressures of supercritical water at any density and temperature with the experimental values is excellent. The second virial coefficient and radial distribution function in ambient and supercritical conditions are also estimated. The radial distributions consist with experimental data very well. [Copyright &y& Elsevier]

Abstract: Chitosan–silica hybrid membranes (CSHMs) were prepared by cross-linking chitosan (CS) with 3-aminopropyl-triethoxysilane (APTEOS). The dynamic behaviors of the CS membrane and the CSHM were investigated in pervaporation (PV) of methanol/dimethyl carbonate (MeOH/DMC) mixtures. The membranes were characterized by X-ray diffraction (XRD), contact angle meter, scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The transition state of PV processes were studied. During the PV processes, the amorphous region of the membranes increases and the contact angle between MeOH and the membrane decreases within a range of operating time and then remains almost constant implying a reconstruction occurred on the membrane surface. The silica is well distributed in the CSHM matrix and the thermal stability of the CSHM is enhanced. The time for a PV process to reach a steady state decreases with increasing MeOH concentration or feed temperature, and it is longer for the CSHM than the CS membrane under the same operating condition. Swelling experiments show that the degree of swelling (DS) is greatly depressed by cross-linking CS with APTEOS. Sorption data indicate that the selectivity of solubility and diffusion of the CSHM are greatly improved over the CS membrane. The CSHM presents superior separation behaviors over other membranes with a flux of and separation factor of 30.1 in PV separation of 70 wt% MeOH in feed at 50 °C. [Copyright &y& Elsevier]

Abstract: Chitosan (CS) was cross-linked with 3-aminopropyl-triethoxysilane (APTEOS) to prepare chitosan–silica hybrid membranes (CSHMs). The CSHMs were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The results show that there are strong hydrogen bond and covalent bonds formed in the CSHMs matrix, the crystallinity of the CSHMs is lower than that of CS, and silica is well distributed in the CSHMs matrix. The CSHMs exhibited a low degree of swelling (DS) in ethanol/water mixture. Both the solubility and diffusion selectivity increase with increasing ethanol content in the range of 55–95wt%. The rate of increase in the solubility selectivity is faster than the rate of decrease in the diffusion selectivity with increasing the feed temperature. These caused the permeate ethanol content to decrease with increasing either the feed ethanol content or the feed temperature. Both the permeation flux and water permselectivity increased remarkably with increasing APTEOS content, CSHM-10 containing 10wt% APTEOS has the highest separation factor of 597 with a flux of 0.887kg/(m2 h) in PV of 85wt% feed ethanol at 323K. [Copyright &y& Elsevier]

Abstract: A methodology based on grand canonical Monte Carlo (GCMC) and NVT-ensemble equilibrium molecular dynamics techniques has been used to simulate the ethanol/water vapor mixture adsorption, diffusion and separation characteristics in silicalite crystal. The adsorption isotherms of pure ethanol and water consist with the literature experimental observations and other algorithm. The ethanol adsorption selectivity first reached the highest value of 85 at a feed ethanol concentration of ∼4vol.% and then decreased with increasing the feed ethanol concentration. This also agreed with the literature experimental investigations. The diffusion coefficients of ethanol and water in the pure and mixture are also estimated by molecular dynamics. The results reveal that the effects of ethanol and water diffusion on separation are slight. We also used the permeation theory to estimate the pure ethanol and water permeance through silicalite membranes. All quantitative agreement of calculations with experiments suggests that the simulation method can be used to predict the performance of zeolite membranes. [Copyright &y& Elsevier]

Abstract: Novel organic–inorganic hybrid membranes were prepared through sol–gel reaction of poly(vinyl alcohol) (PVA) with γ-aminopropyl-triethoxysilane (APTEOS) for pervaporation (PV) separation of ethanol/water mixtures. The membranes were characterized by FTIR, EDX, WXRD and PALS. The amorphous region of the hybrid membranes increased with increasing APTEOS content, and both the free volume and the hydrophilicity of the hybrid membranes increased when APTEOS content was less than 5wt%. The swelling degree of the hybrid membranes has been restrained in an aqueous solution owing to the formation of hydrogen and covalent bonds in the membrane matrix. Permeation flux increased remarkably with APTEOS content increasing, and water permselectivity increased at the same time, the trade-off between the permeation flux and water permselectivity of the hybrid membranes was broken. The sorption selectivity increased with increasing temperature, and decreased with increasing water content. In addition, the diffusion selectivity and diffusion coefficient of the permeants through the hybrid membranes were investigated. The hybrid membrane containing 5wt% APTEOS has highest separation factor of 536.7 at 50°C and permeation flux of 0.0355kgm−2 h−1 in PV separation of 5wt% water in the feed. [Copyright &y& Elsevier]

Abstract: The linear mixed relation for mixed molar volume and free-volume were modified to derive our new activity expression attributed to the combined combinatorial and free volume contributions. The validity and applicability of this expression were demonstrated by calculating the solvent activity in polymer solutions and analyzing the swelling behaviors for polymeric membranes. The average absolute deviation (AAD) of these calculated results from the experimental values of solvent activities for polymer solutions was employed for comparison. It is shown that the modified model can yield better results than the original one for most of the systems considered. The swelling behavior of poly vinyl alcohol (PVA) membranes in water/glycol (EG) mixture over a wide range of concentrations was analyzed. The activity of solvents in the liquid and the membrane was calculated by the UNIQUAC model and this present modified model, respectively. The estimations are consistent with experimental data roughly at temperatures of 333 and 343K. It is found that the modified model is a suitable alternative to the Flory–Huggins equation for the analysis of the swelling behaviors of polymeric membranes in solutions. [Copyright &y& Elsevier]

Silicalite-filled poly(siloxane imide) (PSI) membranes were prepared for the separation of volatile organic compounds (VOCs) from water via pervaporation. PSI copolymer was synthesized by polycondensation of 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) with a siloxane-containing diamine, e.g., poly(dimethylsiloxane), bis(3-aminopropyl) terminated (PSX), added with 3,3-diaminodiphenyl sulfone (DDS). 2,4,6-Triamine pyrimidine (TAP) was added into the casting solution in order to enhance the compatibility between the polymeric matrix and the filler, silicalite. The PSI membranes were characterized by SEM. The surface morphology for the membrane with the addition of TAP differs from that without TAP. The latter seems to be consisting of particles in the membrane surface. The sorption selectivity of the PSI membranes for chloroform/water solutions was investigated, and there was a highest value for it around 50 wt.% of PSX content. The pervaporation performance of the membranes was studied with the separation of chloroform/water mixture. The silicalite-filled membrane with 120 μm thickness exhibit a high total permeation flux of 280 g m−2 h−1 with separation factor of 52.2 for 1.2 wt.% of the chloroform/water mixture. [Copyright &y& Elsevier]

Using a simple activity coefficient model in conjunction with the Vrentas–Duda free-volume (FV) theory, the diffusion behavior of small molecular solvents between and amongst polymer chains is then predicted for several polymer/solvent systems over a wide range of concentrations. The estimations are comparable with experimental data for some systems. For diffusion over- and under-predicted systems, a pre-exponential factor D0 can be adjusted to improve the predictions. It is found that the entropic-FV model is a suitable alternative to the Flory–Huggins equation for predicting mutual-diffusion coefficients in polymeric solutions. To understand the impact of the model on the prediction thoroughly a sensitivity analysis is done for free-volume. The influence of the free-volume of solvent is the opposite of that of the polymer. [Copyright &y& Elsevier]

Catalytic disks of porous ceramic plates supported H3PW12O40 were prepared. Cross-linked poly vinyl alcohol (PVA) composite membranes using the catalytic disks as the matrixes were obtained by spin coating. The dehydration reaction of butanediol (BD) to form tetrahydrofuran (THF) was taken as a model reaction to testify the catalytic activity of the disk, and which was found to be a good catalyst compared with the original H3PW12O40. The separative properties of the membrane were also examined by pervaporation using the same reacting mixture, and the water content in the reactor was much less than THF during the reaction coupled pervaporation. [Copyright &y& Elsevier]

Improving the microphase separation structure of membranes is considered an effective strategy to solve the trade-off problem, which can increase the conductivity and reduce the swelling. This article designs poly(aryl alkylene) AEMs with different aryl backbone chains (biphenyl, p-terphenyl and m-terphenyl), with the goal of examining the effect of spatial structure main chains on the membrane performance. It is found that the membrane (m-QTPNP) has a better microphase separation structure and a conductivity of 143.5 mS cm−1 (80 °C) via SAXS, TEM and AFM. Due to the lower IEC (2.23 meq g−1), m-QTPNP has a good anti-swelling performance. During tensile testing, the elongation at break of m-QTPNP can reach 105.5% (wet state). Moreover, due to the obvious microphase separation, the attack of OH− on the quaternized groups is reduced, and m-QTPNP has a conductivity retention rate of 95.5% (80 °C, 2 M NaOH, 1560 h). In addition, the peak power density (PPD) of the H 2 /O 2 single cell equipped with m-QTPNP can reach 749 mW cm−2 (80 °C). After 90 h of durability testing, the voltage decayed to 92.2%, with a decay rate of 0.54 mV h−1. • The m-QTPNP AEM shows excellent mechanical properties with elongation at break up to 105.5% in wet state. • The m-QTPNP AEM exhibits an ionic conductivity of 143.5 mS cm−1 at 80 °C. • The peak power density of m-QTPNP in a H 2 /O 2 single cell is 749 mW cm−2. [ABSTRACT FROM AUTHOR]

[Display omitted] Anion exchange membrane fuel cells (AEMFCs), which are more economical than proton exchange membrane fuel cells (PEMFCs), stand out in the context of the rapid development of renewable energy. Superacid-catalyzed ether-free aromatic polymers have recently received a lot of attention due to their exceptional performance, but their development has been hampered by the trade-off between the dimensional stability and ionic conductivity of anion exchange membranes (AEMs). Here, we introduced fluoroketones containing different numbers of fluorinated groups (x = 0, 3 and 6) in the main chain of p-terphenyl piperidine because of the favorable hydrophobic properties of fluorinated groups. The results show that fluorinated AEMs can enhance OH− conductivity by building more aggregated hydrophilic channels while ensuring dimensional stability. The PTF6-QAPTP AEM with more fluorinated groups has the most excellent performance at 80 °C with an OH− conductivity of 142.7 mS cm−1 and a swelling ratio (SR) of only 4.55 %. Additionally, it exhibits good alkali durability, with the OH− conductivity and quaternary ammonium (QA) cation retaining at 93.45% and 92.6%, respectively, after immersion in a 2 M NaOH solution at 80 °C for 1200 h. In addition, the power density of the PTF6-QAPTP based single cell reaches 849 mW cm−2 when the current density is 1600 mA cm−2. The PTF6-QAPTP based cell has a voltage retention of 88% after 80 h of stability testing at a constant current density of 300 mA cm−2 at 80 °C. [ABSTRACT FROM AUTHOR]

Extranodal natural killer/T-cell lymphoma (ENKTL) with hepatosplenic involvement is rare, accounting for approximately 0.2% of ENKTL cases. The clinicopathologic features of ENKTL with hepatosplenic involvement are still poorly understood. Seven cases of ENKTL with hepatosplenic involvement were investigated retrospectively by clinical features, pathology, immunophenotype, genotype, Epstein-Barr virus (EBV) status, and survival analysis. The median age was 36 years; three patients (3/7) had a history of primary nasal ENKTL. Six cases (6/7) presented liver or spleen structures that were replaced by neoplasms, and the neoplastic cells displayed diffuse infiltration; one case (1/7) displayed neoplastic cells scattered in hepatic sinuses and portal areas. The cellular morphology and immunohistochemical features were similar to those of ENKTL involving other sites. Follow-up data were available in five of the seven patients. All five patients received first-line chemotherapy based on L-asparaginase. Three patients died, and two were still alive by the last follow-up. The median overall survival (OS) was 21 months. ENKTL with hepatosplenic involvement is rare, regardless of whether it is initial or secondary. There are two histopathologic patterns of ENKTL with hepatosplenic involvement, and L-asparaginase-based chemotherapy combined with AHSCT might yield good efficacy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of crown ether cavity size on the performance of AEMs is investigated. • The QAPCE-18-6 AEM exhibits a highest ionic conductivity of 122.5 mS cm−1 at 80 °C. • The peak power density of QAPCE-18-6 in a H 2 /O 2 single cell is 562 mW cm−2. Anion exchange membrane fuel cells (AEMFCs) have emerged as a promising alternative to proton exchange membrane fuel cells (PEMFCs) due to their adaptability to low-cost stack components and non-noble-metals catalysts. However, the poor alkaline resistance and low OH− conductivity of anion exchange membranes (AEMs) have impeded the large-scale implementation of AEMFCs. Herein, the preparation of a new type of AEMs with crown ether macrocycles in their main chains via a one-pot superacid catalyzed reaction was reported. The study aimed to examine the influence of crown ether cavity size on the phase separation structure, ionic conductivity and alkali resistance of anion exchange membranes. Attributed to the self-assembly of crown ethers, the poly (crown ether) (PCE) AEMs with dibenzo-18-crown-6-ether (QAPCE-18-6) exhibit an obvious phase separated structure and a maximum OH− conductivity of 122.5 mS cm−1 at 80 °C (ionic exchange capacity is 1.51 meq g−1). QAPCE-18-6 shows a good alkali resistance with the OH− conductivity retention of 94.5% albeit being treated in a harsh alkali condition. Moreover, the hydrogen/oxygen single cell equipped with QAPCE-18-6 can achieve a peak power density (PPD) of 574 mW cm−2 at a current density of 1.39 A cm−2. [ABSTRACT FROM AUTHOR]

Background Pseudoaneurysmal epistaxis is a rare but emergent condition. We report a case of traumatic anterior cerebral artery pseudoaneurysmal epistaxis and review the published literature. Case Description A 49-year-old man sustained severe head trauma. He was diagnosed with multiple skull bone fractures, left subdural hematoma, subarachnoid hemorrhage, pneumocephalus, and right frontal hematoma. Subdural hematoma evacuation was done at a local hospital. In the following months, he experienced repeated epistaxis that required nasal packing to stop the bleeding. Digital subtraction angiography showed an anterior cerebral artery pseudoaneurysm protruding into the posterior ethmoid sinus. Embolization of the aneurysm was performed with microcoils, and the parent artery was occluded by thrombosis. The patient presented 1 month later with another epistaxis episode. Digital subtraction angiography showed recanalization of the parent artery and recurrence of the aneurysm. The parent artery was occluded for the second time with coils and Onyx embolic agent. Conclusions Pseudoaneurysmal epistaxis is rare, and this is the first report of an anterior cerebral artery pseudoaneurysm that manifested with epistaxis. Endovascular intervention has become the first choice of treatment for this disease. The high recurrence rate is the main disadvantage of endovascular intervention. Aneurysm trapping with bypass surgery is another treatment option. [ABSTRACT FROM AUTHOR]

[Display omitted] Poly(aryl piperidinium) (PAP) anion exchange membranes (AEMs) furnish an important avenue for the commercialization of anion exchange membrane fuel cells (AEMFCs), but their ionic conductivity and alkali resistance still need to be improved. Here, we report the synthesis of PAP AEMs with a branched structure by the acid-catalyzed reaction and compare them with the main-chain AEMs. The experimental results show that the branched AEMs have higher OH− conductivity and alkaline resistance than the poly(terphenyl piperidine) (PTPQ1) AEM. The alkaline stability and OH− conductivity of the AEMs were further improved by a flexible multi-cation crosslinker. The results show that the branched poly(p-terphenyl triphenylmethane 1-methyl piperidine) membrane crosslinked by multi-cation (PTTPQ4-40) shows an excellent OH− conductivity (155.3 mS cm−1) at 80 °C. The OH− conductivity of the PTTPQ4-40 membrane was maintained at 92.1% after soaking in 2 M NaOH for 1080 h at 80 °C. In addition, the peak power density (PPD) of the crosslinked PTTPQ4-40 membrane can reach 656.7 mW cm−2. Compared to the PTPQ1 AEM, the PPD of the crosslinked PTTPQ4-40 AEM is increased by 38.6% in H 2 -O 2. All of the results confirm that the PTTPQ4-40 AEM has excellent fuel cell application prospects. [ABSTRACT FROM AUTHOR]

Evolutionary breakdown from rigorous outbreeding to self‐fertilization frequently occurs in angiosperms. Since the pollinators are not necessary, self‐compatible populations often reduce investment in floral display characteristics and pollination reward. Primula forbesii is a biennial herb with distribution restricted to southwest China; it was initially a self‐incompatible distylous species, but after 20 years of artificial domestication, homostyly appeared. This change in style provides an ideal material to explore the time required for plant mating systems to adapt to new environmental changes and test whether flower attraction has reduced following transitions to selfing. We did a survey in wild populations of P. forbesii where its seeds were originally collected 20 years ago and recorded the floral morph frequencies and morphologies. The floral morphologies, self‐incompatibility, floral scent, and pollinator visitation between distyly and homostyly were compared in greenhouse. Floral morph frequencies of wild populations did not change, while the cultivated population was inclined to L‐morph and produced homostyly. Evidence from stigma papillae and pollen size supports the hypothesis that the homostyly possibly originated from mutations of large effect genes in distylous linkage region. Transitions to self‐compatible homostyly are accompanied by smaller corolla size, lower amounts of terpenoids, especially linalool and higher amounts of fatty acid derivatives. The main pollinators in the greenhouse were short‐tongued Apis cerana. However, homostyly had reduced visiting frequency. The mating system of P. forbesii changed rapidly in just about 20 years of domestication, and our findings confirm the hypothesis that the transition to selfing is accompanied by decreased flower attraction. [ABSTRACT FROM AUTHOR]

It is an important research topic to construct microphase separation in anion exchange membranes (AEMs). The integration of rigid anthracene units into the main chains to form poly(anthracene- co - p -terphenyl piperidinium) AEMs is a new method by using π-π stacking to regulate microphase separation and construct ion transport channels in membranes. In this study, anthracene units were introduced for the first time to prepare AEMs with different anthracene contents. It is found that the introduction of rigid anthracene units into the backbone leads to an increase in the fractional free volume (FFV) of the membranes and a decrease in the ion conductive resistance. Moreover, the existence of long flexible di-piperidinium side chain helps to adjust the rigidity of the AEMs and enhances the mechanical properties of the membrane. The ionic conductivity of PA10TP-DMP is 153.8 mS cm−1 (80 °C). In the meanwhile, the conductivity retention of 91.7 % was observed after the alkaline resistance test (80 °C, 2 M NaOH) for 1200 h. In addition, the PA10TP-DMP based H 2 –O 2 single cell has a peak power density of 840.3 mW cm−2 and a high durability after 100 h test. [Display omitted] • Poly(anthracene- co - p -terphenyl piperidinium) AEMs were prepared by introducing anthracene units. • The presence of rigid anthracene units increases the free volume and π-π stacking in the membrane. • The introduction of anthracene segment promotes microphase separation to obtain high conductivity. • The highest power density reaches up to 840.3 mW cm−2 in H 2 –O 2. [ABSTRACT FROM AUTHOR]

To investigate the effect of the monomer with different flexibility and rigidity on the random copolymer, we prepare anion exchange membranes (AEMs) with a similar copolymerization ratio containing different monomers. The results show that the introduction of rigid dibenzofuran, moderately flexible diphenyl ether and flexible bibenzyl affects the conformation and morphology of the polymers, further tuning the overall performance of the AEMs. The three random copolymers exhibit better microphase-separated morphology and conductivity than the homopolymer owing to their more twisted conformation. It is found that the incorporation of flexible monomers has an advantage in holding size consistence and flexibility. Overall, the integration of bibenzyl monomer has the most positive impact on the membrane characteristics, the QPIBBP-40 AEM with flexible units possesses the highest OH− conductivity (80 °C, 159.6 mS cm−1) and an excellent mechanical stability (elongation at break: 48.2 %, tensile strength: 15.6 MPa). The wet-stated QPIBBP-40 AEM maintains an inferior swelling ratio (80 °C, 10.8 %), indicating that it possesses good size consistence and ionic conductivity simultaneously. The highest output power density of the QPIBBP-40 AEM based fuel cell is 655 mW cm−2. [Display omitted] • A series of novel poly(isatin biphenyl) copolymers were designed. • Radom copolymerization is a facile and effective way to tune properties of AEM. • Rigid or flexible monomers on the conformation of the backbone were investigated. • Flexible bibenzyl units have advantages on boosting conductivity. [ABSTRACT FROM AUTHOR]

Anion exchange membranes (AEMs) are one of the most critical materials determining the fuel cell (FC) performance. From current reports, there are still many limit factors for AEMs, such as conductivity, mechanical performance, power density and durability, which greatly affect their practicality. Here, we introduce a range of arylfluoroketone monomers with different side chain lengths into the poly (aryl-alkylene) matrix material using a copolymerization strategy to get AEMs. This study aims to investigate the effect of side chain length on the performance of AEMs, such as phase separation, ion conductivity and mechanical properties. Due to the existence of long alkyl side chains, QTPNPC4 shows significant hydrophilic aggregation, outstanding OH− conductivity (158.6 mS cm−1, 80 °C) and excellent flexibility (109.1 %). Meanwhile, QTPNPC4 exhibits remarkable ex-situ durability (96.3 %) and chemical stability (96.6 %) after soaking in a 2 M NaOH solution for 1560 h at 80 °C. In addition, the peak power density (PPD) of a single cell with QTPNPC4 reaches 927 mW cm−2 (80 °C), and the membrane has good in-situ durability (0.689 mV h−1). [Display omitted] • QTPNPC4 shows the elongation at break up to 109.1 % in wet state. • QTPNPC4 exhibits a highest ion conductivity of 158.6 mS cm−1 at 80 °C. • The peak power density of a QTPNPC4-based single cell is 927 mW cm−2. [ABSTRACT FROM AUTHOR]

As the core material of alkaline fuel cells, anion exchange membranes (AEMs) are one of the keys to determining the comprehensive performance of fuel cells. However, drawbacks, such as impoverished alkali stability, insufficient mechanical properties, and particularly low ionic conductivity, affect their application in fuel cells. Herein, a series of AEMs based on a new arylfluoroketone monomer [1-bromo-3- (trifluoroacetyl phenyl)-propane, TFAP-Br] was prepared using a backbone modification strategy. This study aims to investigate the effects of introducing TFAP-Br for copolymerization on the microphase separation, ionic conductivity, and mechanical properties of AEMs. Due to the presence of long side chains of alkylfluoroketone and arylfluoroketone, the AEMs exhibit a prominent microphase separation state, and the OH− conductivity can reach 156 mS cm−1 at 80 °C (IEC = 2.73 meq g−1). QBPNP-10 shows excellent mechanical properties with the elongation at break up to 91% in wet state and good alkali resistance with 95.2% OH− conductivity retention in a NaOH solution (2 mol L−1, 80 °C, 1560 h). Moreover, the peak power density (PPD) of a single cell assembled with QBPNP-10 can reach 852 mW cm−2 (80 °C), and the membrane has good in-situ durability. [Display omitted] • The QBPNP-10 AEM shows excellent mechanical properties with elongation at break up to 91% in wet state. • The QBPNP-10 AEM exhibits a highest ionic conductivity of 156 mS cm−1 at 80 °C. • The peak power density of QBPNP-10 in a H 2 /O 2 single cell is 852 mW cm−2. [ABSTRACT FROM AUTHOR]

A kind of anion exchange membranes (AEMs) with C C bond end-group crosslinked structure was synthesized successfully. Unlike the traditional aliphatic AEMs, the AEMs were prepared in this work by a strategy to realize the C C bond thermal end-group crosslinking reaction, exhibiting an obvious microphase separation structure and a suitable dimensional stability. The well-defined ion channels constructed in the AEMs guarantee the fast OH− conduction, as confirmed via physical and chemical characterization. The conductivity was dramatically enhanced due to the effective ion channels and increased ion exchange capacity. Among the as-prepared AEMs, the PHFB-VBC-DQ-80% AEM has a conductivity of 135.80 mS cm−1 at 80 °C. The single cell based on PHFB-VBC-DQ-80% can achieve a power density of 141.7 mW cm−2 at a current density of 260 mA cm−2 at 80 °C. The AEMs show good thermal stability verified by a thermogravimetric analyzer (TGA). Furthermore, the ionic conductivity of PHFB-VBC-DQ-80% only decreased by 7.1% after being soaked in a 2 M NaOH solution at 80 °C for 500 h. [Display omitted] • C C bond was introduced into an AEM to form end-group crosslinked structure. • The AEMs possess an obvious microphase separation structure. • PHFB-VBC-DQ-80% has a conductivity of 135.80 mS cm−1 at 80 °C. • The AEMs with C C crosslinker possess good chemical stability. [ABSTRACT FROM AUTHOR]

Phytoremediation technology can help achieve moderate cost and considerable effect with respect to the remediation of heavy metal (HM) pollution in soil and water. Many previous studies have suggested the role of nitrogen (N) in the alleviation of effects of HM on plants. Herein, we sought to determine the molecular mechanisms by which additional N supplementation mitigates cadmium (Cd) toxicity in poplars using a combination of physiological, transcriptomic and phosphoproteomic analyses. The application of N can alleviate the toxicity of Cd to Populus by reducing chlorophyll degradation, maintaining the stability of ions inside and outside the cell membrane and increasing the soluble sugar content. Plant samples from the control, Cd stress and Cd_N treatments were used for an integrated analysis of the transcriptome, as well as for phosphoproteomics analysis. Moreover, 1314 differentially expressed genes and 119 differentially expressed kinase genes were discovered. Application of additional N under Cd stress promoted the phosphorylation process. Furthermore, 51 significantly enriched phosphorylated protein sites and 23 differentially expressed kinases were identified using phosphoproteomic and proteomic analyses. Importantly, transcriptomic and phosphoproteomic analyses jointly determined that the application of N could activate corresponding gene expression [ UDP-glucose-dehydrogenase (UGD), GAUT , PME , pectin lyase , UDP-glucose-pyrophosphorylase 2 (UGP2), sucrose phosphate synthase (SPS), SUS and SPP2 ] and protein phosphorylation (UGP2 and SPS) in the sugar and starch synthesis pathways, which promoted the synthesis of sucrose and soluble sugar and subsequently alleviated the damage caused by Cd. [ABSTRACT FROM AUTHOR]

WO3 thin films were sputtered onto alumina substrates by DC facing-target magnetron sputtering. One sample was rapid-thermal-annealed (RTA) at 600 °C in a gas mixture of N2:O2 = 4 : 1, and as a comparison, another was conventionally thermal-annealed at 600 °C in air. The morphology of both was investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM), and the crystallization structure and phase identification were characterized by X-ray diffraction (XRD). The NO2-sensing measurements were taken under LED light at room temperature. The sensitivity of the RTA-treated sample was found to be high, up to nearly 100, whereas the sensitivity of the conventionally thermal-annealed sample was about five under the same conditions. From the much better selectivity and response-recovery characteristics, it can be concluded that compared to conventional thermal annealing, RTA has a greater effect on the NO2-sensing properties of WO3 thin films. [ABSTRACT FROM AUTHOR]

Abstract: Membranes based on sulfonated polyarylethersulfone with cardo (SPES-C) were prepared and characterized using Fourier transform infrared (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and contact angle metering. The results show that both the hydrophilicity and amorphous region of the membranes increased with increasing sulfonation degree (SD). Sulfonic acid groups exist as a form of ion clusters and homogeneously distribute in the membranes leading to a depression in their crystallinity and an increase in the interaction between methanol and the membranes. The effects of SD on the swelling and separation performance of the membranes were studied. The SPES-C membrane with excellent thermal stability is found to have improved performance when the SD is 0.64. A flux of 4.06kgμmm−2 h−1 and separation factor of 1300 at 40°C are achieved in pervaporation of 15wt% methanol/methyl tert-butyl ether mixture. [Copyright &y& Elsevier]

Abstract: Novel polyelectrolytes complex (PEC)/11-phosphotungstic acid hydrate (PW11) hybrid membranes (PEC/PW11) were prepared by blending sodium alginate (SA) and gelatin (GE), followed by incorporating with PW11, and then crosslinking by γ-Glycidoxypropyltrimethoxysilane (GPTEOS). Structures of the membranes were characterized by X-ray diffraction (XRD), FT-IR, thermogravimetry (TG), scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle goniometer methods. The characterization results demonstrated that the amorphous regions in the membrane and hydrophilicity of the membrane enhance with increasing PW11 content; thermal stability of the membrane strengthened with the introducing of PW11; PW11 was homogeneously dispersed in the PEC matrix when PW11 content was no higher than 9wt%. Swelling experiments showed that the degree of swelling (DS) of the PEC/PW11 hybrid membranes increased with increasing PW11 content or water content in feed. Sorption experiments demonstrated that when PW11 was no more than 9wt%, both the sorption selectivity and diffusion selectivity increase with increasing PW11 content, then decrease with further increasing PW11 content. PEC/PW11 hybrid membrane containing 9wt% PW11 exhibited the best pervaporation performance, whose averaged permeation flux was 0.440kg/m2/h and separation factor was 144 for 90wt% aqueous solution of acetic acid at 50°C. [Copyright &y& Elsevier]