Adsorption of pure and mixed CO 2 and N 2 is simulated in a mimetic MCM-41. The full-atom MCM-41 model is constructed by caving cylindrical pores from an amorphous silica matrix and energetically optimized. Dreiding force field is used for the dispersive interaction with the atomic charges estimated from the densityfunctional theory calculations. The optimized MCM-41 maintains a hexagonal array of the mesoscopic pores as evidenced by the three characteristic peaks in the XRD pattern. The pore surface of MCM-41 is corrugated and coated with hydroxyls and defects. The pore size exhibits a Gaussian distribution with an average radius of 14.38 Å close to the experimental value. Simulated adsorption isotherms and isosteric heats of CO 2 match well with the experimental data. CO 2 adsorbs preferentially at the active sites near the pore surface, while N 2 tends to adsorb homogeneously on the pore surface. In CO 2 and N 2 mixture as a flue gas, CO 2 is more adsorbed than N 2 . The selectivity of CO 2 over N 2 drops rapidly with increasing temperature and depends weakly on pressure. At temperatures higher than 400 K, the selectivity approaches a constant and pressure has no discernible effect.

Two important issues in skin tissue engineering are the vascularization and regeneration of the dermis. Basic fibroblast growth factor (bFGF) is known to promote angiogenesis and accelerate wound healing. Direct delivery of bFGF to the wound area, however, would lead to a loss of bioactivity. To this end, bFGF-loaded alginate microspheres (Ms) were fabricated and incorporated into carboxymethyl chitosan (CMCS)-poly(vinyl alcohol) (PVA) to form a composite hydrogel. Scanning electron microscopy (SEM) results indicated that the incorporation of Ms does not significantly affect the inner structure of CMCS-PVA. In an in vitro study, the release of bFGF from Ms-CMCS-PVA in a sustained manner retained higher bioactivity over a 2-week period. Full-thickness burn wounds were created in the dorsal area of rats for in vivo evaluation of skin regeneration treated with CMCS-PVA hydrogel, with and without bFGF. Compared with the control, CMCS-PVA and bFGF-CMCS-PVA groups, the bFGF/Ms-CMCS-PVA group revealed significantly faster wound recovery rates, with re-epithelialization and regeneration of the dermis. Moreover, the bFGF/Ms-CMCS-PVA group had the highest density of newly formed and mature blood vessels during the 2 mweek treatment period. The ability of the bFGF/Ms-CMCS-PVA hydrogel to accelerate wound healing in a full-thickness burn model suggests its potential for use in dermal tissue regeneration. Copyright © 2015 John Wiley & Sons, Ltd.

Summary: Using bond length fluctuation and cavity diffusion algorithm, the morphologies of diblock copolymer/homopolymer blend films, AB/C and AB/A, confined between two hard walls are studied via Monte Carlo (MC) simulation on a cubic lattice. For the AB/C film, the C homopolymer is supposed to be more compatible with the A block than with the B block, while A and B are mutually incompatible. Effects of the composition of the diblock copolymer/homopolymer mixture, the symmetry of the diblock copolymer chain, the film thickness and the selective wall field on morphologies are studied in detail. Furthermore, the simulated results are compared with that of corresponding ABA and ABC triblock copolymer thin films. Comparisons with experiments and SCF theory also show good agreement. The results indicate that both the AB/C and AB/A can be used to prepare porous AB diblock copolymer membranes, the size of the pore channel can be controlled by the volume fraction of homopolymer C or homopolymer A.

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The extensive research and developments of highly efficient oxygen electrode electrocatalysts to get rid of the kinetic barriers for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are very important in energy conversion and storage devices. Especially, exploring nonprecious metal alternatives to replace traditional noble metal catalysts with high cost and poor durability is the paramount mission. In this paper, we utilize property-flexible ZIF-67 and sulfur-functionalized graphene oxide to obtain a cobalt, nitrogen, and sulfur codoped nanomaterial with 3D hierarchical porous structures, owing to their rich dopant species and good conductivity. The crosslinked structures of polyhedron particles throughout the whole carbon framework speeds up the mass transportation and charge-delivery processes during oxygen-evolving reactions. Also, by exploring the location and coordination type of sulfur dopants, we emphasize the effects of sulfone and sulfide functional groups anchored into the graphitic structure on enhancing the catalytic abilities for ORR and OER. To note, compared to the noble metal electrocatalysts, the best-performing CoO@CoO/NSG-650 (0.79 V) is 40 mV less active than the commercial Pt/C catalyst (0.83 V) for ORR and merely 10 mV behind IrO (1.68 V) for OER. Besides, the metric between ORR and OER difference for CoO@CoO/NSG-650 to evaluate its overall electrocatalytic activity is 0.90 V, surpassing 290 and 430 mV over Pt/C (1.19 V) and IrO (1.33 V). Comprehensively, the as-prepared CoO@CoO/NSG-650 indicates excellent bifunctional catalytic activities for ORR and OER, which shows great potential for replacing noble metal catalysts in the application of fuel cells and metal-air batteries.