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© 2017 Majid Asnavandi et al. The failures of superheater and reheater boiler tubes operating in a power plant utilizing natural gas or mazut as a fuel have been analysed and the fire-side corrosion has been suggested as the main reason for the failure in boiler tubes. The tubes have been provided by a fossil fuel power plant in Iran and optical and electron microscopy investigations have been performed on the tubes as well as the corrosion products on their surfaces. The results showed that the thickness of the failed tubes is not uniform which suggests that fire-side corrosion has happened on the tubes. Fire-side corrosion is caused by the reaction of combustion products with oxide layers on the tube surface resulting in metal loss and consequently tubes fracture. However, the tubes corrosion behaviour did not follow the conventional models of the fire-side corrosion. Given that, using the corrosion monitoring techniques for these boiler tubes seems essential. As a result, the thickness of the boiler tubes in different parts of the boiler has been recorded and critical points are selected accordingly. Such critical points are selected for installation of corrosion monitoring probes.

Cell behaviour changes as a result of the local environment, particularly when transitioning from two dimensional (2D) to three dimensional (3D) environments. It has been acknowledged that there is a need for efficient, tuneable and reproducible methods for making 3D cell cultures to further understand cell behaviour in 3D environments. The development of extracellular matrix (ECM) mimics has gained popularity as a way to create highly tuneable materials that resemble the native environment around cells. The modular nature of synthetic hydrogels means that they have the potential as ECM mimics for 3D cell cultures with tuneable mechanical and chemical properties. Herein, reversible addition fragmentation chain transfer (RAFT) polymerisation was used to synthesise poly(ethylene glycol)methyl ether acrylate (PEGMEA). Hydrogels with tuneable mechanical and cell adhesive properties were synthesised. Norbornene was used as a functional unit for both crosslinking and addition of biomolecules via thiol-ene click chemistry. To obviate the need for UV light for cross-linking of the hydrogel, visible light stimulated eosin-Y was used to induce the thiol-ene reaction. Pancreatic cancer cells (KrasG12D and p53R172H) were seeded on the hydrogels to confirm that the cytotoxicity of the hydrogels was low. The attachment of CRGDS onto the hydrogel was demonstrated as a means to improve cell adhesion.