Responsive functional composite fibre mats that are mechanically stable and impervious to water exposure are produced by coaxial electrospinning of thermotropic liquid crystal (LC) core inside a water-based solution of poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA) forming the sheath. Because thermotropic LCs usually cannot be spun inside water-based solutions due to excessive interfacial tension γ, a n enabling step is the addition of ethanol or dioxane to the LC as a co-solvent compatible with both core and sheath fluids. This reduces γ sufficiently that coaxial jet spinning is possible. After spinning, thermal cross-linking of the PVA+PAA sheath yields LC-functionalised fibres that can be manipulated by hand and remain intact even upon full immersion in water. The LC core retains its behaviour, nematics showing well-aligned birefringence and transitioning to isotropic upon heating above the clearing point, and cholesterics showing selective reflection which is even enhanced upon water immersion due to the removal of sheath scattering. Our results pave the way to producing LC-functionalised responsive fibre mats using durable polymer sheaths, thereby enabling numerous innovative applications in wearable technology, and they also open new opportunities to study LCs in confinement, without visible impact of the container walls.

Hyaluronic acid (HA) is a polyanionic natural polymer occurring as a linear polysaccharide composed of glucuronic acid and N-acetylglucosamine repeats. Hyaluronic acid has a wide range of applications with its excellent physicochemical properties such as biodegradability, biocompatibility, non-toxicity, non-immunogenicity and serves as an excellent tool in biomedical applications such as osteoarthritis surgery, ocular surgery, plastic surgery, tissue engineering and drug delivery. This work provides an overview on hyaluronic acid, its chemistry and biochemistry and its medical applications.

Bone tissue engineering applications demand for biomaterials offering a substrate for cell adhesion, migration, and proliferation, while inferring suitable mechanical properties to the construct. In the present study, polyurethane (PU) foams were synthesized to develop a graded porous material-characterized by a dense shell and a porous core-for the treatment of oro-maxillary bone defects. Foam was synthesized via a one-pot reaction starting from a polyisocyanate and a biocompatible polyester diol, using water as a foaming agent. Different foaming conditions were examined, with the aim of creating a dense/porous functional graded material that would perform at the same time as an osteoconductive scaffold for bone defect regeneration and as a membrane-barrier to gingival tissue ingrowth. The obtained PU was characterized in terms of morphological and mechanical properties. Biocompatibility assessment was performed in combination with bone-marrow-derived human mesenchymal stromal cells (hBMSCs). Our findings confirm that the material is potentially suitable for guided bone regeneration applications.

Porphyrins coated ZnO is an interesting material where the exposure to light and gas may cooperate to modulate the respective sensitivities. In this work, the gas sensing properties of porphyrins functionalized laterally grown ZnO nanorods are introduced. The porphyrin layer incompletely coats the semiconductor surface in order to keep both ZnO and porphyrins in contact with analyte. It is known that UV light may prompt the chemical sensitivity of ZnO replacing the high temperature condition. Here we demonstrate that because of the photo-injection of electrons from porphyrin to the ZnO, the same impact could be acquired with visible light.

La0.8Sr0.2Ga0.8Mg0.2O3−δ (LSGM) perovskite oxide was selected as electrolyte to fabricate reduced-temperature solid oxide fuel cells (SOFCs). Porous/dense ceramic bilayers were optimized by using different pore forming agents. Reduced temperature (700°C) infiltration method was employed to obtain anodes with nano-sized metal oxidation catalysts. The type and amount of porogen necessary to get a proper anodic porosity were evaluated together with the amount of infiltrated Ni catalyst to obtain promising electrochemical results.

TPS-T1-10 Nanostructured ZnO/SnO2 gas sensors via microemulsion synthesis method # 1 Chemical and Biochemical Sensors Fahimeh Hoori-Abad Saboor, Mehrdad Asgari, Yadollah Mortazavi, Abbas Ali Khodadadi Heteronanostructures of ZnO/SnO2 was synthesized through two different synthesis procedures in microemulsion system of TritonX100/hexanol/cyclohexane. Response of these nanoparticles to CO, CH4 and EtOH was measured and compared with bare ZnO nanoparticles. Different sensing behavior was observed when Sn precursor was added sequentially to a microemulsio of ZnO nanoparticles (ZS1) than coprecipitation of Zn and Sn in the microemulsion (ZS2). For all gases, a decrease in Tmax was observed for ZS1 compared to the bare ZnO. Moreover, the responses to CO and CH4 were considerably higher for ZS1 than ZS2. The obvious difference in the BET surface area of ZS1(56 m2/gr), ZS2(132 m2/gr) and ZnO (36 m2/gr) nanoparticles, show significant changes in nucleation/growth mechanism of SnO2 nanoparticles in two procedures. Catalysis and Nanostructured Materials Research Laboratory, School of Chemical Engineering, University of Tehran, Tehran, Iran Iran

A solvent-driven aggregation of a porphyrin derivative linked to glycosylated-steroid moieties results in the formation of chiral supramolecular species, whose morphology and spectroscopic features depends on the mechanism of interaction, and on the concentration of the macrocycles.

Dense micrometric La0.8Sr0.2Ga0.8Mg0.2O3-δ (LSGM) films were deposited by spin-coating on porous LSGM scaffolds characterized by homogeneous pore structure. Porous anodes were infiltrated with aqueous nickel and nickel/copper nitrate solutions, dried and fired at 700 °C. Homogeneous metal coating with proper interconnection was observed by SEM, chemical stability confirmed by XRD, and electrical characterization of anodic substrates was performed. Catalytic activity of different anodes was evaluated ex-situ in a quartz micro-reactor fed with CH4:CO2 mixture at range 650 and 700 °C. To investigate the redox properties of the metallic phases, the anodic substrates were subjected to redox ageing cycles and characterized by H2-TPR.