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The work presented in the thesis describes the preparation and characterisation of nanoparticle-carbon nanotube composite structures by transmission electron microscopy (TEM) and their applications in catalysis and biomedicine. Identical location TEM (IL-TEM) was utilised for the first time to study the nanoscale structure of composites of catalytic metallic nanoparticles and hollow carbon nanotubes in macroscale, liquid-phase, preparative reactions. IL-TEM analysis of palladium nanoparticles confined within graphitised nanofibres (GNF) indicated that the catalytic nanoparticles undergo changes in mean size and size-dependent migrations within the internal channel of GNF under the conditions of Suzuki-Miyaura reactions. IL-TEM analysis of copper nanoparticles in GNF showed dissolution and reprecipitation of the nanoparticles into strand-like nanostructures under the conditions of the “click” reaction, indicating the pseudo-homogeneous mechanism of this catalysed chemical transformation. A series of metal nanoparticle-GNF catalysts were subject to a range of elevated temperatures and gaseous environments and the corresponding structure-function relationships explored. A copper nanoparticle-GNF catalyst was applied in the industrially-significant water-gas shift reaction (WGSR) and compared to a commercially available, metal oxide-supported catalyst. The commercial catalyst exhibited minimal and expected changes in composition under the WGSR and generally remained stable with no changes in mean size or shape of catalytic nanoparticles. In contrast, the structure and composition of both the catalytic nanoparticles and the GNF substrate was found to significantly change in the novel nanoparticle-GNF catalyst. The effect of pre-treatment temperatures and gaseous environments on the composition and structure of three separate palladium, gold and copper nanoparticle-GNF systems was appraised, evidencing clear structure-function relationships between the size and/or composition of the catalysts at the nanoscale with their catalytic properties (selectivity and/or activity) at the macroscale. Molecule-nanotube interactions were studied towards the development of an effective controlled drug release system. The uptake and release of a chemotherapeutic agent, doxorubicin, from carbon, boron nitride and titania nanotubes, and their corresponding gold nanoparticle composites, was studied. No release of doxorubicin was observed for any structure, even with a plasmonic heating-induced release mechanism for the gold nanoparticle-nanotube composites, due to the strength of the host-guest interaction between the drug and the nanotubes.

The analyses of spray, combustion and emission characteristics for two types of biodiesel fuels, namely coconut methyl ester (CME) and soybean methyl ester (SME) are reported in this thesis. In order to produce high fidelity numerical spray and combustion representation for CME and SME, accurately developed thermo-physical properties and chemical kinetics were integrated with open-source computational fluid dynamics codes. First, the thermo-physical properties of CME and SME which include liquid and vapour properties were calculated using temperature-dependent correlations that were found in the literature. These calculated thermo-physical properties were then incorporated into Open Field Operation and Manipulation (OpenFOAM) to determine the sensitivities of the fuel properties on the spray development. Based on the sensitivity analyses, 5 of 12 thermo-physical properties, including latent heat of vaporisation, liquid density, liquid heat capacity, liquid surface tension and vapour pressure, gave the largest fluctuation to the spray development. Besides, coupled effects among the thermo-physical properties were discovered. The effects of thermo-physical properties were also varied according to the addition of unsaturation levels and combustion chemistries. Next, a generic reduced chemical kinetic mechanism, with components of methyl decanoate, methyl-9-decenoate and n-heptane was developed to represent the biodiesel fuels. The reduced mechanism with 92 species and 360 elementary reactions was validated under 72 shock tube conditions against experimental measurements in the literature and detailed mechanism predictions, for each zero-dimensional auto-ignition and extinction process using CHEMKIN-PRO. Maximum percentage errors of less than 40.0% were recorded when the ignition delay (ID) period predictions of the reduced mechanism were compared to those of detailed mechanism. Satisfactory agreement was attained when the predictions of the reduced mechanism were validated against the measured species profiles of rapeseed methyl ester oxidation in jet stirred reactor, which were obtained from the literature. Besides, the ID periods and lift-off lengths (LOL) predicted for the reacting spray at initial temperatures of 900 K and 1000 K achieved a maximum deviation of 29.8% and 43.4%, respectively, as compared to those of the experimental measurements in the literature. CME and SME were then numerically analysed under both the conditions of constant volume bomb and diesel engine, using the validated thermo-physical properties and reduced mechanism. The ambient oxygen level of the constant volume bomb was raised from 15.0 to 21.0% to emulate the intake air composition in the diesel engine. As such, the spray development was changed from radial to forward propagation, where LOL was reduced by 24.3%. Higher levels of carbon monoxide (CO), carbon dioxide (CO2) and soot mass concentrations were also obtained. When the unsaturation level was increased from 20.0% (CME) to 80.0% (SME), retarded spray and combustion developments were found in both the constant volume bomb and diesel engine. Besides, the CO, soot and nitric oxide (NO) emissions, including the tailpipe predictions were maximally increased by 32.0%. In overall, CME performs better than SME does because of the improved air-fuel mixing and decreased tailpipe NO, CO and CO2 emissions. Based on these, it is sufficient to deduce that the phenomena predicted in the constant volume bomb are adequate to replicate those in the diesel engine.

The work presented herein focused on the automation of coordination-driven self assembly, exploring methods that allow syntheses to be followed more closely while forming new ligands, as part of the fundamental study of the digitization of chemical synthesis and discovery. Whilst the control and understanding of the principle of pre-organization and self-sorting under non-equilibrium conditions remains a key goal, a clear gap has been identified in the absence of approaches that can permit fast screening and real-time observation of the reaction process under different conditions. A firm emphasis was thus placed on the realization of an autonomous chemical robot, which can not only monitor and manipulate coordination chemistry in real-time, but can also allow the exploration of a large chemical parameter space defined by the ligand building blocks and the metal to coordinate. The self-assembly of imine ligands with copper and nickel cations has been studied in a multi-step approach using a self-built flow system capable of automatically controlling the liquid-handling and collecting data in real-time using a benchtop MS and NMR spectrometer. This study led to the identification of a transient Cu(I) species in situ which allows for the formation of dimeric and trimeric carbonato bridged Cu(II) assemblies. Furthermore, new Ni(II) complexes and more remarkably also a new binuclear Cu(I) complex, which usually requires long and laborious inert conditions, could be isolated. The study was then expanded to the autonomous optimization of the ligand synthesis by enabling feedback control on the chemical system via benchtop NMR. The synthesis of new polydentate ligands has emerged as a result of the study aiming to enhance the complexity of the chemical system to accelerate the discovery of new complexes. This type of ligand consists of 1-pyridinyl-4-imino-1,2,3-triazole units, which can coordinate with different metal salts. The studies to test for the CuAAC synthesis via microwave lead to the discovery of four new Cu complexes, one of them being a coordination polymer obtained from a solvent dependent crystallization technique. With the goal of easier integration into an automated system, copper tubing has been exploited as the chemical reactor for the synthesis of this ligand, as it efficiently enhances the rate of the triazole formation and consequently promotes the formation of the full ligand in high yields within two hours. Lastly, the digitization of coordination-driven self-assembly has been realized for the first time using an in-house autonomous chemical robot, herein named the ‘Finder’. The chemical parameter space to explore was defined by the selection of six variables, which consist of the ligand precursors necessary to form complex ligands (aldehydes, alkineamines and azides), of the metal salt solutions and of other reaction parameters – duration, temperature and reagent volumes. The platform was assembled using rounded bottom flasks, flow syringe pumps, copper tubing, as an active reactor, and in-line analytics – a pH meter probe, a UV-vis flow cell and a benchtop MS. The control over the system was then obtained with an algorithm capable of autonomously focusing the experiments on the most reactive region (by avoiding areas of low interest) of the chemical parameter space to explore. This study led to interesting observations, such as metal exchange phenomena, and also to the autonomous discovery of self assembled structures in solution and solid state – such as 1-pyridinyl-4-imino-1,2,3-triazole based Fe complexes and two helicates based on the same ligand coordination motif.

The main objective of this thesis is to develop relatively simple but reasonable engineering models within a CFD software framework to simulate fire in a compartment and fire growth and propagation in enclosures in which solid combustibles are involved through wall or ceiling linings. Gas phase combustion, radiation and solid fuel combustion are addressed in this study. At the heart of this study is the integration of the three sub-models representing the key elements mentioned above in compartment fire development and other auxiliary calculations such as the evaluation of the radiative properties of gas-soot mixture, temperature calculation for non-burning solid surfaces, etc. into a complete fire spread model. Shortcomings in the conventional six-flux radiation model are highlighted. These were demonstrated through a simple artificial test case and corrected in the modified six-flux model. The computational cost and accuracy of the six-flux model and the discrete transfer method (DTM) using different number of rays are also investigated. A simple empirical soot model is developed based on experimental observations that soot formation occurs in the fuel rich side of the chemical reaction region and the highest soot concentration is found in the same region. The soot model is important to evaluate the radiative properties of the gas-soot mixture in fires. By incorporating the gas-phase combustion model, the radiation models and the soot model, substantial improvement in the predicted upper layer temperature profiles is achieved in the simulations of one of the Steckler's room fire test. It is found that radiation plays an important, perhaps dominant role in creating the nearly uniform temperature distribution in the upper layer. The integral method to calculate temperatures of non-combustible solids is extended to be capable of dealing with the non-linearity of the reradiation at the solid surface(top surface) exposed to a fire and the convective heat loss at the opposite surface. The integral method is economic and simple for the calculation of temperatures of non-combustible solids. Pyrolysis models for nonchaning and charring solid combustibles are developed. The mass loss rates produced by the noncharring model for PMMA are in excellent agreement with experimental data. The charring model produced predictions for the mass loss rates and temperature distribution of a wood sample in very close agreement to that measured. Finally, qualitative and quantitative verifications for the integrated fire spread model are carried out. The model is demonstrated to be capable of both qualitatively and quantitatively predicting fire, fire growth and development within compartment fire scenarios.

The aims of this project were to synthesise and characterise a range of inorganic/organic hybrid polymers containing pendant vinyl groups and to study their uses as possible fire retardants. The work consisted of several parallel strands: the synthesis of organically modified silicas; the preparation of vinyl containing silsesquioxanes based on the hydrolysis of cyclohexyltrichlorosilane or propylmethacrylatepolysiloxane; the synthesis of latexes by co-polymerisation of either N-Isopropylacrylamide (NIPAM) or styrene with vinyltrimethoxysilane and the intercalation of styrene or NIPAM into montmorillonite. All samples were characterised using a range of instrumental techniques including infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR), X-ray diffraction (XRD), elemental analysis, thermal analysis, surface area analysis and electrokinetic analysis. Vinyl modified silicas having large surface areas (about 400m2g-1) were successfully obtained. On calcining at 540°C silicas having surface area in excess of 1000m2g-1 were formed. Both the original organically modified silica and a sample after calcining were incorporated into poly(methylmethacrylate) and these samples were compared with pure poly(methymethacrylate) in a cone calorimeter to study their thermal properties. No significant enhancement to the thermal stability of the polymers was observed when the silica was incorporated. Analysis of the co-polymer latexes were inconclusive, in the case of the products obtained from NIPAM but particles having a narrow size distribution were obtained using styrene. There was no apparent trend in the value of the zeta potential with composition. Analysis of the intercalation of monomers into clays and the synthesis of silsesquioxanes were inconclusive.