The ability to predict the lifetime performance of an SOFC can give guidelines for where improvements can be made in terms of production, operating parameters and cell design. Microstructural analysis ofNi-YSZ anode samples under varying steam and temperature regimes was investigated to determine trends in the anode Ni particle growth. Increasing the steam content produced larger mean Ni radii for a given temperature. Higher operating temperatures (900°C) were shown to have a significant accelerating effect on the particle size change. Further analysis of the microstructural data highlighted profiles for Ni-pore contact angle 9 values, as well as Triple Phase Boundary points and overlap length which both showed a decrease over time, highlighting differences in the rate of performance loss in the anode. Using models derived for the degradation mechanisms combined with a particle packing model, Matlab® coding was developed to predict the Ni particle growth rate and the relative change in conductivity and TPB length per unit volume. Ni particle growth rate predictions were compared to experimental results and showed good correlation. The data can be used to help design accelerated testing procedures for SOFC anodes to determine the long term performance of a given anode composition.

Functional food ingredients such as prebiotics are emerging as effective tools for managing the risks associated with gastrointestinal diseases and gut related dysfunctions. This work explores the production of prebiotic rich extracts from two sources of lignocellulosic biomass – energy crop \(Miscanthus\) \(χ\) \(giganteus\), and oat (\(Avena\) \(sativa\)) husks, an agricultural by-product. Whilst most of the research to date has been focusing on the utility of cellulose, the hemicellulose and lignin fractions have been underutilised. This work expands the value of the hemicellulose fraction by extracting the prebiotic xylo-oligosaccharides (XOS) and other hemicellulose derived products using environmentally benign sub-critical water in a 0.5 L stirred batch reactor at temperatures between 120-220°C with residence times 0-77 min, and 0.5-13% (w/v) biomass loading. The extracts were analysed with HPAEC-PAD, HPLC and colorimetric assays. Almost complete hemicellulose solubilisation was achieved, and highest yields of prebiotic (DP 2-5) XOS were observed at 170°C and 35-77 min corresponding to 44-56% with little amounts of carbohydrate degradation products and low total phenolic contents. Although higher yields were achieved with oat husks, the XOS extractability was comparable between the biomass sources. Higher extraction severities resulted in further XOS depolymerisation into monosaccharides and eventual formation of furfural and 5-HMF.

Fab fragments are invaluable for therapeutic and diagnosis purposes. The robust and low cost Escherichia coli expression system for Fab production seems promising. However, Fab production in E. coli currently suffers from low yield and poor solubility. In this study, E. coli strain CLD048 was initially employed for the production of Fab D1.3 target yield of ≥ 100 mg/L. Unfortunately, the fermentation was unsuccessful. Thus, several strategies for improving Fab production were explored. Consequently, the majority of Fab was accumulated in the periplasm, the overall Fab yield was increased and the solubility of Fab D1.3 was improved. Subsequently, optimising release conditions for periplasmic proteins was investigated. A successful fermentation was demonstrated by expressing A33 Fab' in E. coli strain W3110 (yield ≥ 300 mg/L in the periplasm). Various selective protein release methods were investigated. Crude E. coli periplasmic extract containing A33 Fab' was directly employed in the AMTPS, which successfully demonstrated the feasibility of continuous protein separation with a highly purified final product (~98%). In other work, thermo-responsive polymer brush surface modified M-PVA were benchmarked against Chelating Sepharose Fast Flow. Two coloured proteins were employed to exploit the feasibility of thermally mediated target protein elution under binding conditions.

The performance of KM static mixers has been assessed for the blending of Newtonian and time-independent non-Newtonian fluids using planar laser induced fluorescence (PLIF). A stream of dye is injected at the mixer inlet and the distribution of dye at the mixer outlet is analyzed from images obtained across the pipe cross section. The effect of superficial velocity, scale of static mixer, flow ratio between a primary and a secondary injected flow and finally the injection position, are investigated to determine the consequences on mixing performance. Different methods are discussed to characterize mixing performance, comparing CoV and maximum striation thickness. Conflicting trends are revealed in some experiments results, leading to the development of an areal based distribution of mixing intensity and a distribution of striation with high mixing intensity. For two-fluids blending, the addition of a high viscosity stream into the lower viscosity main flow causes very poor mixing performance, with unmixed spots of more viscous component observable in the PLIF image. The final part of the work is focused on a preliminary understanding of advective mechanisms such as shearing of non-Newtonian fluid drops and stretching of a non- Newtonian fluid filaments.

The droplet size distribution produced by the atomization system within a spray d1yer is vital in defining the output particle size distribution, which in turn can strongly influence the subsequent flow, dissolution, ingestion or bioavailability of the final product. This thesis explores the capability of a simple atomizing system for the production of narrow droplet size distributions within an industrially-relevant spray dryer. The combination of constrained droplet size distribution, defined solute concentration and selected processing conditions has been evaluated to determine the influence upon the physicochemical properties of a model active pharmaceutical ingredient, and the dosing characteristics of formulated products. The flow focusing atomizer was demonstrated to be capable of generating distinct droplet size distributions, and able to produce similar performance in the dynamic environment within a spray dryer. Experiments conducted using the inhaled corticosteroid mometasone furoate indicate that droplet size, concentration and drying conditions are important in determining the particle size, texture and thermodynamic properties of the output powder. Analysis of formulations containing the flow-focused mometasone furoate particles defined a clear link between the impaction profile in a cascade impactor and droplet size and spray d1ying conditions.

The long-term stability and brittle nature of ceramic bone replacements in physiological conditions makes them prone to mechanical failure. These problems have led to the development of bioresorbable bone replacement materials. Bioresorbable biomaterials are expected to degrade at a rate which is proportional to the rate of formation of new bone tissue. In the majority of cases, however, resorption is driven by simple dissolution and so it is difficult to ensure an appropriate degradation rate for all patients. This thesis seeks to develop a material that can degrade in response to the bone formation process, thus linking implant resorption to tissue formation. We have shown that this can be achieved by linking implant resorption to a biological stimulus, such as the enzyme alkaline phosphatase (ALP), which is found on the surface of bone forming cells (osteoblasts). ALP causes bone mineralisation by removing the pyrophosphate (P\(_2\)O\(_7\)\(^4\)\(^-\)) ion, a known inhibitor to calcium phosphate formation. By removing the P\(_2\)O\(_7\)\(^4\)\(^-\) P2O74- ions from solution the dissolution of calcium pyrophosphate ((Ca\(_2\)P\(_2\)O\(_7\)\(^4\)\(^-\)) crystals were accelerated in accordance with Le Chetalier's principle. We demonstrated that for this accelerated dissolution to occur, the ALP did not require access to the crystal surface. This is contrary to previous work which suggested that CPPD dissolution occurred as a result of ALP cleaving the crystal surface. Bulk (Ca\(_2\)P\(_2\)O\(_7\)\ ceramics were successfully produced by sintering brushite cement at temperatures ≥ 400°C, the dissolution of which could accelerated in the presence of ALP but was heavily dependent on material specific surface area. The process of sintering limits the possibility of producing biomaterials of complex morphology; therefore the final part of this thesis involved the fabrication of ((Ca\(_2\)P\(_2\)O\(_7\) ceramic using stereolithography.

The recycling of a foundry ceramic waste from investment casting has been investigated. The waste was reduced in size by fly pressing and disc milling to d50 < 20 μm and cleaned by magnetic separation and acid leaching. The powder contained zircon, alumina and amorphous silica with 37, 38 and 24 wt. % (ZrSiO4: Al2O3: SiO2) respectively. Two products were targeted: zirconia toughened mullite (ZTM) ceramics produced with an addition of alumina and zircon based pigments developed by the removal of alumina and reaction with colourant ions. With an addition of 23.5 wt. % Al2O3, a ZTM containing 30 wt. % zirconia and 70 wt. % mullite exhibiting strength, hardness, thermal shock resistance and toughness commensurate with data reported in the literature were developed. Milling in isopropanol, dry pressing and sintering at 1600 ℃ for two hours optimised the properties. The transition to ZTM appeared to be through an intermediate glassy phase and limited by the dissociation of ZrSiO4. It was estimated that 70 % of the ZrO2 was transformable tetragonal without the addition of Y2O3. With Y2O3 non-transformable tetragonal ZrO2 was produced. It was shown that a clean zircon powder free of Al2O3 was generated by reaction with K2S2O7. Dissociation-synthesis and direct-synthesis routes were used to produce pigment. It was found that higher reaction temperature and the introduction of flux can significantly increase yellowness. The yellow produced from waste materials performed as well as those from commercial grade feeds.

Acoustic agitation of a carbon dioxide/water mixture in a 1 dm3 cylindrical, high-pressure reactor led to the simultaneous formation of carbon dioxide/water (C/W) and water/carbon dioxide (W/C) emulsions, with the dispersed phase occupying up to 10% of the volume. These emulsions were stable for several minutes. Inclusion of 1% of the non-ionic surfactant Tween 80 led to the generation of C/W emulsions which were stable for over 1 hour after ceasing sonication, in which all of the carbon dioxide present in the system comprised the dispersed phase. The mixing capacity of pulsed ultrasound was assessed by studying the mass transfer of benzaldehyde across the carbon dioxide/water interface, leading to determination of the system mixing time. A model for mass transfer with a fast chemical reaction, namely the hydrolysis of benzoyl chloride, was used to separate the mass transfer and kinetic effects, and to identify those reactions that would most significantly benefit from ultrasound-induced emulsification. For the first time, the Barbier synthesis was shown to occur in a carbon dioxide/water mixture as solvent, leading to moderate to high yields. Moreover, it was possible to recover the homoallylic alcohol product directly from the carbon dioxide phase in which it was preferentially partitioned.

Recombinant protein production (RPP) is a cornerstone of bioprocessing. This study presents novel analytical techniques and production protocols for RPP in E. coli, particularly regarding industrial applications. Flow cytometry (FCM) was used to monitor cell physiology and RPP during production of a fluorescent model protein, CheY::GFP. Further applications of FCM for monitoring RPP were developed: The amyloidophilic dye Congo red was used to identify inclusion bodies produced under high-stress conditions. FCM analysis of transformants on agar plates identified 3 populations of varying fluorescence intensity and the progressive transfer of cells from the high fluorescence population to one of intermediate fluorescence and low culturability. Congo red staining showed this was due to amyloid-inclusion body formation. RPP conditions that minimise physiological stress by reducing temperature and inducer concentration can increase product yields, solubility and biomass yields. The original fermentation protocol used for stress-minimised RPP proved unsuitable for industrial use. Application of stress-minimisation to an industrially-derived protocol using early or late-phase induction and glucose or glycerol as carbon source generated high biomass, total CheY::GFP and soluble CheY::GFP yields. These protocols improved biomass generation, product formation and reproducibility over the original stress-minimised and unmodified industrially-derived protocols and therefore stress-minimisation is of potential industrial use.

Polyethylene terephthalate (PET) films can be advantageously utilised to replace both glass and metal in photovoltaic (PV) devices. However, there remain aspects of their performance in outdoor applications which may be improved upon to meet PV device requirements more efficiently. DuPont Teijin Films (DTF) employ artificial weathering techniques to investigate PET film degradation processes, such as UV degradation and hydrolysis, which occur during the outdoor application of PET films. In this Thesis, a thorough investigation into the modification of PET film properties with exposure to various artificial weathering techniques has been conducted. Techniques including infra-red spectroscopy, gel permeation chromatography, atomic force microscopy and nano-indentation have been employed to improve the understanding of the effects of artificial weathering on PET films. The effects of exposure to high intensity simulated solar radiation have also been investigated and compared with those of the combined degradation agents present during ISO standard accelerated environmental weathering. Surface modifications have been compared with those of the bulk, in particular, surface roughening and microcracking have been investigated in much greater detail than previously in the literature. Finally, the stabilizing effects of including an organic ultraviolet absorber on weathered PET film bulk and surface properties have also been assessed.