Water-in-oil-in-water (W/O/W) double emulsion systems provide an innovative approach for the development of low-fat healthier foods. By replacing a proportion of the oil phase of a simple oil-in-water (O/W) emulsion with an internal water phase, the overall oil volume within the emulsion system can be decreased, with potentially negligible changes to its organoleptic properties. However, double emulsions are notoriously unstable for adequate periods of time, largely due to the existence of two oppositely curved water-oil (W/O) and oil-water (O/W) interfaces in close proximity. The present study investigates the use of Pickering stabilisation in order to enhance the stability of double emulsions. Pickering stabilisation mechanisms are reputed for superior, longer term stabilisation capacities when compared to conventional surfactant stabilised emulsions, but edible particles with Pickering functionality are scarce. The work in this thesis explores the impact of introducing Pickering stabilisation to a double emulsion structure, initially at only one of the two water/oil interfaces (either W/O or O/W) and ultimately across the entire interfacial areas. Initial work conducted centred on investigating the role of a range of edible particulates as potential Pickering stabilisers in simple emulsions (both W/O and O/W emulsion types). Based on the knowledge gained from these studies, a range of Pickering-Surfactant stabilised double emulsions (with particles or surfactant stabilising alternate interfaces), using a range of surfactants, and Pickering only stabilised double emulsion systems were prepared and analysed in terms of their microstructure, stability and encapsulation efficiencies.

The work presented within this thesis focuses on the synthesis, characterisation and processing of novel materials for use within solid oxide fuel cells. A range of perovskite materials, previously shown to have potential for solid oxide fuel cell applications, were selected for further studies. These included LaMnO\(_3\), SrFeO\(_{3-δ}\) and Sr\(_{0.8}\)Ti\(_{0.6}\)Nb\(_{0.4}\)O\(_{3-δ}\). These materials were doped with various dopants, including cations such as V\(^{5+}\) and Ti\(^{4+}\) and also SiO\(_4\)\(^{4-}\) oxyanions. Once doped, the materials were analysed by X-ray powder diffraction and underwent testing to ascertain their suitability for use as solid oxide fuel cell electrodes. This included identifying structural stability in anode conditions alongside thermal expansion studies. Overall, improvements over undoped samples were noted, especially for Sr\(_{0.8}\)Ti\(_{0.6}\)Nb\(_{0.4}\)O\(_{3-δ}\) samples doped with V\(^{5+}\) and SrFeO\(_{3-δ}\) samples doped with SiO\(_4\)\(^{4-}\), although LaMnO\(_3\) doped with Ti\(^{4+}\) proved less successful. Production methods for the formation of microtubular solid oxide fuel cells were also investigated. Powder processing for paste formation was examined, for subsequent use in extrusion. The extrusion process was also investigated, alongside debinding and sintering studies. The development of a reliable and repeatable process for cell production proved difficult, especially on a smaller scale necessary to facilitate the testing of novel materials.

In modern Internal Combustion (IC) engines, the fuel spray atomization process is known to play a key role in affecting mixture formation, combustion efficiency and soot emissions. Therefore, a thorough understanding of the fuel spray characteristics and atomization process is of great importance. In this study, the fuel spray of modern Gasoline Direct Injection (GDI) engines and diesel engines has been experimentally and numerically studied. At the same time, optimized physical-numerical spray breakup models for the spray simulation have been developed and validated.

When a computer program requires legitimate access to confidential data, the question arises whether such a program may reveal sensitive information to an unauthorised observer. There is therefore a need to ensure that a program, which processes confidential data, is free of unwanted information flow. This thesis presents a formal framework for the analysis and enforcement of secure information flow in computational systems such as computer programs. An important aspect of the problem of secure information flow is the development of policies by which we can express intended information release. For this reason information lattices and maps on these lattices are presented as models, which capture intuitive notions about information and information flow. A definition of security is given, based on the lattice formalisation of information and information flow, that exploits the partial order of the information lattice. The lattice formalisation gives us a uniform way to enforce information security policies under various qualitative and quantitative representations of information. An input-output relational model, which describes how a system transforms its input to publicly observable outputs with respect to a given attacker model, is presented as a primitive for the study of secure information flow. By using the relational model, various representations of information, which are shown to fit into the lattice model of information, are derived for the analysis of information flow under deterministic and nondeterministic system models. A systematic technique to derive the relational model of a system, under a given attacker model, from the operational semantics in a language-based setting, is also presented. This allows the development of information flow analyses parametrised by chosen attacker models. A flow-sensitive and termination-sensitive static analysis calculus is presented for the analysis of information flow in programs written in a deterministic While language with outputs. The analysis is shown to be correct with respect to an attacker model that is able to observe all program outputs and which can determine the termination or nontermination of program execution. The static analysis also detects certain disjunctive information release. A termination-sensitive dependency analysis is developed which demonstrates how, by employing abstract interpretation techniques, other less precise but possibly more efficient information flow analysis may be obtained. The thesis concludes with further examples to highlight various aspects of the information flow analysis and enforcement framework developed.

As the focus of research on ‘adaptive/responsive’ surfaces has in recent years contributed strongly towards the design of surface materials with ‘intelligent’ or ‘smart’ behaviour, current superparamagnetic adsorbents being employed both in small and large scale operations can be surface modified and improved by gaining dual functionalities. In this work, modification of M-PVA supports with polymer brushes of dual properties has been explored for their intended use in bioseparation technology, i.e. for both selectively protein binding and enhanced temperature elution of especially difficult to elute species such as haemoglobin. Tethering of polymer brushes was achieved by employing two different ‘grafting from’ routes, i.e. cerium (IV) initiated polymerisation and Atom Transfer Polymerisation Reaction (ATRP). By identifying the optimum cerium (IV) reaction conditions, the said chemistry was further utilised to attach different polymers (thermoresponsive and affinity ligands) and their combination (thermo-affinity) at fixed positions onto M-PVA supports, either as di-block or mixed functionality polymer brushes. The configuration of introduced polymer chains as well as the haemoglobin binding characteristics of the above materials was evaluated, and their efficiency for haemoglobin and GFP desorption via sequential temperature transitions was demonstrated. Mixed polymer brushes manufactured using sequential ATRP after partial bromination of AGE activated magnetic supports were characterised and tested likewise. Protein binding and release efficiency was dependent on brush configuration (length and spacing between the graft sites of polymers), pNIPAAm content, type of affinity ligand and type of protein employed. From the above materials those with polymer chains of sufficient pNIPAAm length and at such spacing allowing their ‘free’ expansion/collapse upon temperature change (especially those grafted via cerium (IV) route) were found efficient, as brush behaviour favour enhanced desorption of difficult to elute species.

An artificial liposome membrane system has been employed for in vitro screening of the human absorption of biologically active molecules for applications in nutrition and drug treatments. Initial work with molecules having small permeabilities demonstrated that they could not be measured using the technique since they were absorbed by the membrane. A critical innovation was to pre-treat the membrane by equilibrating it with the molecule of interest since this avoids the absorption problem but required more complex data analysis. Bioactive molecules with strong antioxidant and anti-cancer activity extracted from green tea showed a strong affinity to the membrane, which suggests that this significantly limits bioavailability. Ethanol but not dimethyl sulfoxide (DMSO) was found to enhance the diffusion of paracetamol, theophylline, acyclovir, nadolol and amphotericin B. The potential synergistic effect on the diffusion of paracetamol in the presence of caffeine was investigated but it was shown to have a detrimental effect. Finally, an effective protection of Epigallocatechin-3-gallate (EGCG) from the environment was achieved by the preparation of beeswax microspheres as a carrier.

The creation of drops from the growth of surface tension instabilities on the surface of liquid jets has been exploited in many industrial applications. Curved jets are relevant to prilling, which creates small spherical pellets from molten material. There is a need to optimise the process to produce pellets of uniform size. The dynamics of the break-up of curved jets is examined, with experiments investigating the effect of scale, rheology and surface tension, with particular focus on pseudoplastic liquids, using laboratory and pilot-scale facilities. The experiments were compared to previous work on Newtonian fluids, and existing numerical simulations, which use the method of finite differences to solve non-linear evolution equations for jet radius and axial velocity. The effect of non-Newtonian rheology on the trajectory of the jet and linear instability are determined using computational and asymptotic methods. The droplet sizes produced by this instability are determined by considering the most unstable wave mode. This enables quantitative comparison with the experiments. The influence of multiple disturbance frequencies (imparted by mechanical vibrations) on the break-up of curved Newtonian jets is investigated. Experimental data was compared with existing numerical models, to see if it is possible to predict where satellite droplets are eradicated.

The research in this thesis aimed to study efficiency and viability of supercritical water oxidation (SCWO) technology in treating diluted N,N-dimethylformamide (DMF), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and ammonia containing model wastewaters that were selected due to their hazard, wide usage in industry and having different degrees of refractoriness. A lab-scale SCWO tubular reactor was operated to obtain necessary data to investigate the destruction of selected compounds at certain operating conditions in addition to studying the oxidation kinetics of DMF and DBU. Also, Isopropyl Alcohol was used to enhance the destruction of treating DMF, DBU and ammonia. Results showed that temperature was the most influential variable where near complete TOC removal was obtained during DMF and DBU oxidation at 525oC and 250 bars. Temperatures of 400-550oC were not enough to achieve a significant destruction for ammonia. Organic concentrations and oxidant ratios also showed positive effects on the destruction of DMF, DBU and ammonia. IPA showed an essential role to destroy DMF, DBU and ammonia when used where a TOC removal of 99.4% and 99.2% was achieved for DMF and DBU respectively at 525oC and 250 bars and maximum TN removal of 97% was obtained at 550oC and 250 bars during ammonia oxidation. Also the presence of IPA reduced the activation energy of treated compounds where the values were 21.9 and 25.7 kJ/mol for DMF and DBU, respectively. Also it was found that oxygen has an influence and with oxygen order of 0.38 and 0.32 for DMF and DBU respectively.

This project investigated how various minerals of different surface areas and morphologies can be used to adsorb isothiazoline biocides for controlled-release and antimicrobial purposes. The absorption of the biocides on the mineral powders was achieved by way of using a bench high shear mill (dry process), or combining them to hydrated minerals (wet process). The characterisation of the minerals was achieved by XRF (chemical composition), XRD (crystal composition), SEM (morphology), B.E.T nitrogen (surface area), and Light Scattering (particle size distribution). HPLC was used to determine the concentration of the biocide in solution, and the Flow Microcalorimeter used to measure the bond strength between the biocide molecules and the minerals. The minerals were added to an exterior paint made according to an Imerys in-house formulation. Various modifications of this initial coating formulation were made in order to compare the biocide 2-Octyl-4-isothiazolin-3-one (OIT) release profiles from impregnated and non-impregnated minerals. Montmorillonite clay was the best performing mineral in all experiments (adsorption and desorption both from the minerals and paints films, strength of bond analysis, and bioassay). All other minerals tested carried the biocide with varying degree of success. Optical and mechanical tests performed on paint films containing various minerals suggested there were no significant differences between the films. Rheology tests demonstrated that newly developed formulations were easy to apply to a surface.

Water-in-oil emulsions have the potential to eradicate drying of the lips caused by constant lipstick application by improving moisturising properties and delivering hydrophilic molecules to the lips. To conduct this research, a food microstructure approach was utilised developing emulsion structures’ using either a batch or continuous process and monitoring the affect these structures had on physical and material properties. The lubricating properties of emulsions structures were then compared to a trained sensory panel. Finally the release behaviour of a moisturising agent was investigated. It was shown that the ingredients used to produce the microstructure are pivotal in indicating the melting profile, droplet size and material properties of the final structure. Specifically, when an aqueous phase is incorporated within a hard shell the elastic modulus increases as the aqueous phase become part of the wax network. The effect of lubrication showed that friction coefficient of a solid emulsion could be related to how smooth a lipstick would be perceived based on the Kokani Model. Finally, it was shown that the release of a moisturising agent is governed by the droplet size and the amount of destruction caused to the wax network.