Energy is an important requirement for population growth, technological progress and urbanisation. Worldwide energy demand has been projected to increase by 5-fold by 2100. Fulfilment of these energy requirements cannot be solely from fossil fuels, such as oil, coal and natural gas, on account of their adverse environmental impacts and concomitant depletion of natural resources. As a result multiple approaches for generating alternative energy are being explored globally. In this study, processed municipal solid waste (MSW) fibre was assessed as a substrate for the production of various bio-energy related products. The MSW was characterised and the results showed that there was, as expected, a wide compositional variation between samples. There was a significant amount of lignocellulosic material found in some samples and the potential to exploit this to generate fermentable sugars was explored. Direct enzyme hydrolysis using 30 FPU (Filter Paper Units)/g Cellic® CTec2 gave a 30 % release of available glucose. Pre-treatments- using hot water, dilute acid and dilute alkali are all applied to enhance sugar release but were all found to be ineffective. The possibility of using MSW as a substrate for cellulase enzyme production via solid state fermentation (SSF) by Trichoderma reesei (T. reesei) and Aspergillus niger (A. niger) was explored. Both fungi grew well on the substrate and following optimization a cellulase activity of 26.10±3.09 FPU/g could be produced using T. reesei at 30 °C with a moisture content of 60 % with inoculation of 0.5 million spores/g and incubation for 168 hr. Addition of extra nitrogen and/or carbon did not improve cellulase accumulation. Acid or alkali pre-treatment of MSW led to reduced cellulase production. Crude enzymes produced from MSW by T. reesei were evaluated for their ability to release glucose from MSW. A cellulose hydrolysis yield of cellulase was 24.7 % achieved, which was close to that obtained using a commercial enzyme. Results demonstrated that MSW could be used as an inexpensive lignocellulosic material for the production of cellulase enzymes. High concentrations of toxic heavy metals were found in all MSW samples tested and this precludes the use of this material as a soil enhancer. Thus studies were undertaken to explore the potential for bioleaching as a means to generate compost that meets environmental standards for safe use. A. niger and Saccharomyces cerevisiae NCYC2592 were used and the impact of growth medium and pH tested. Both organisms were effective at solubilising the heavy metals and this may be related to their ability to synthesise organic acids into the fermentation medium that act as chelators.

Computer aided molecular design (CAMD) is a powerful technique to design molecules or chemical mixtures that fulfil a set of desirable target properties as specified by users. Molecular physical and thermodynamic properties are selected as the target properties to ensure that the designed molecules can achieve the property functionalities. However, the aspects of safety and health are not strongly emphasised as design objectives in many CAMD problems. In order to ensure that the synthesised molecule does not cause much harm and health-related risks to the consumers, it is critical to integrate both safety and health aspects as design factors in the current CAMD approaches. The main focus of this research is to develop a novel chemical product design methodology that integrates the concept of inherent safety and occupational health aspects in a CAMD framework. The generated molecules that are optimised with respect to the target properties must be evaluated in terms of their safety and health performance. The assessment is conducted by safety and health-related parameters/sub-indexes that have significant adverse impact on both aspects. This proposed approach ensures that a product that possesses the desirable properties, and at the same time meets the safety and health criteria, is produced. The next focus of this research is to generate optimal molecules with the desired functionalities and favourable safety and health attributes in a single-stage CAMD framework. Besides target properties, the concept of inherent safety and health is also considered as design objective to ensure that the synthesised molecules are simultaneously optimised with regards to both criteria. Fuzzy optimisation approach is applied to optimise these two principal design criteria in this work. As molecular properties are utilised as the parameters to examine the safety and health features of the molecules, these properties are often estimated through property prediction models. This research also focuses on the management of uncertainty resulted from properties used in the sub-indexes. The quantification of uncertainty helps to revise the safety and health measurement so that it can better reflect the inherent hazard level of the molecules. The fourth focus of this research is to address the limitations present in the current method of molecular hazard quantification. The enhancement is carried out by adopting the ordered weighted averaging (OWA) operator method with the analytic hierarchy process (AHP) approach in the safety and health assessment. Two case studies on solvent design are considered to demonstrate the presented methodologies.

After the oil crisis held in 1973 and 1979, academicians and industry players have noticed the importance and necessity of having alternative and sustainable energy sources in future. Biological wastes, also named as “Biomass” has been cited as one of the significant sustainable energy sources. Biomass poses an ideal and substantial potential to achieve a sustainable system. However, the development of biomass industry is still relatively sluggish due to the lack of confidence of the investor to venture in this relatively new green business. This is most probably attributed to the low-maturation of biomass technologies compared to other conventional technologies, high logistics cost required for biomass transportation and uncertain market penetration barrier for the biomass-derived products. This raises the importance of having a proper biomass management system and a systematic evaluation approach to assess the sustainability performances of the biomass industry. Therefore, the ultimate goal of this thesis is to develop a sustainable multi-biomass supply chain with the aims of optimising all three sustainability dimensions simultaneously. A sustainable multi-biomass supply chain is referred as the integrated value chain of the green products, which derived from various types of biomass, starting from harvesting stage to the final products delivery stage. This thesis discusses in detail on the relevant previous research works toward the introduction of novel evaluation approach to attain different sustainable objectives (i.e., economic, environmental and social) simultaneously. The evaluation approach encompasses various components, including (i) model reduction by using P-graph integrated two-stage optimisation approach; (ii) consideration of vehicle capacity constraint for detailed transportation cost estimation; (iii) integration of various sustainability indexes using various optimisation techniques. On top of that, two novel debottlenecking approaches, one through principal component analysis (PCA) method; while another through P-graph framework, which able to identify and remove barriers that limit the sustainability performance of the biomass supply chain, are proposed. Aside from this, this thesis also aims to reduce the gaps between the researchers and industry players by developing some user-friendly and non-programming-background dependent decision-making tools. Thus, decision-makers are able to understand the insight of their problems easily without requirement of strong mathematical background. A case study in Johor, a southern state in Malaysia, which is endowed with extensive biomass resources, is used to demonstrate the effective of the proposed approaches.

The United Nations FAO (Food and Agriculture Organization) reports that a large quantity of global food production for human consumption is wasted every year (1.3 billion tons) with losses estimated between 40 and 50 % for all root and tuber crops, fruits and vegetables (FAO Global Initiative on Food Loss and Waste Reduction). Potatoes tubers are one the worldwide staple foods with an annual total production of circa 368 million tons. A major contributor to this loss is potato infection whilst in storage (in the UK circa 5% of the entire UK crop), with the main culprit being a disease of bacterial origin known as ‘soft rot’. This project attempts to address this post-harvest waste of potato tubers in storage through early detection and monitoring of the disease. The proposed approach for this research was to use gas phase biomarkers for the early detection of soft rot (in other words ‘smelling’ the disease). The first part of the project addressed past research on volatile detection and background on other sensing technologies not previously (or marginally) investigated in these studies. The section on past studies includes all the research carried out from the 1970s by Varns and Glyn to date. Most of the studies focused on Gas Chromatography or Gas Chromatography Mass Spectroscopy. The background section that follows addresses other technologies that could also be employed for volatile monitoring, namely Field Asymmetric Ion mobility Spectrometry, Photoionization Detection, Metal Oxide, Electrochemical, and Nondispersive Infrared gas sensors. Initial work focused on evaluating these gas sensing technologies for both symptomatic and pre-symptomatic progression of potato soft rot, under laboratory conditions. After preliminary investigation, the experimental method chosen consisted in assessing the sensors results at two time points, both for symptomatic and pre-symptomatic disease detection. A total of 80 potato samples (40 for each time point) were tested with 25 different gas sensors. To process the data the following techniques were employed: cumulative sensor responses, unsupervised PCA and k-means and machine learning models (LDA, MARS, SVM, random forest and the C5.0 algorithm). Results show that all these techniques yielded a very high discrimination rate between healthy control and diseased tubers (with 80 to 100% accuracy) for a number of sensors. PID, 3 metal oxide and 3 electrochemical, gas sensors were shortlisted for possible later work. The final part of the project focussed on deploying sensors identified in laboratory conditions in a real store. To this end, a bespoke instrument was developed solely for the monitoring of store environments. The instrument comprised the sensors tested in the previous part of this work that could be readily embedded into a research tool for in-situ experimentation (with the addition of few others for completeness). Three electrochemical, six metal oxide, one nondispersive infrared and the PID sensors were included in the unit. The experimental method employed was based on time course varying from few days to two weeks. Two types of experiments were carried out, namely laboratory work and store room monitoring. Time series results for four types of sample types (unwounded controls, wounded controls and two infected sets) show that some of the sensors (ethanol, ammonia, hydrocarbons, overall volatiles and carbon monoxide) deployed on the instrument could discriminate between the various sample batches and detect soft rot from a very early stage and throughout the experimental work. The bespoke instrument was then deployed in a research store setting for testing (at the AHDB Sutton Bridge Crop Storage Research Centre, UK). Four 1 ton wooden crates controls were placed inside a (56 m3) store room (at 95% RH and 15 ± 1 °C) followed after the fourth day by a batch of infected tubers (with a proportion of infected tubers to controls of 1%). Results over a period of circa three weeks show that some of the sensors (ethanol, ammonia and hydrocarbons) could detect soft rot from a very early stage and throughout the experimental work. In conclusion, the research reported here shows that gas analysis technology could be successfully applied for pre-symptomatic detection and monitoring of soft rot in a storage facility with readily available commercial sensors.

Chapter 1 Reviews the synthesis of polyolefin block copolymers, focussing on strategies involving catalytic coordination polymerisation to produce end-functionalised polyolefins followed by the growth of a second block from the reactive end group using living/controlled techniques. The advantages and disadvantages of the various literature methods are discussed. Chapter 2 Discusses the utilisation of the Catalytic Hydride Insertion Polymerisation (CHIP) mechanism for the synthesis of low molecular weight polyethylene macromonomers by manipulating the relative concentrations of dihydrogen and ethylene in the reactions. The application of the mechanism is investigated further with the introduction of two non-styrenic comonomers 5-vinyl-2-norbornene and 5-ethylidene-2-norbornene. Observations made when we studied the effects of comonomer concentration and dihydrogen partial pressure on the products are discussed and some mechanistic insights for the copolymerisation between ethylene and norbornene derivatives in the presence of dihydrogen are proposed. Chapter 3 Focusses on the investigation of the mechanism for the copolymerisation between the PE-i-DIB macromonomer and n-butyl acrylate using a small-scale batch process and a larger scale starved feed semi-batch process. Observations are found to be consistent with a reversible cross-propagation mechanism between PE-i-DIB and the propagating P(n-BA) chain in which the continued availability of monomer is key to the lifetime of the process, as demonstrated by the difference in the evolution of molecular weight in the batch and semi-batch processes. The semi-batch process also provides superior control over the copolymerisation compared to the batch process. Chapter 4 Investigates the versatility of the PE-i-DIB macromonomer in copolymerisations with several other types of polar monomer. Copolymer products with vinyl esters, methacrylates and styrenes are synthesised and the challenges provided by the new monomer types are discussed. The products discussed here and in Chapter 3 are characterised by NMR, GPC, DLS and DSC and the evidence is found to be consistent with the presence of block copolymers. Chapter 5 Describes the testing of some of the block copolymers synthesised in Chapters 3 and 4 for their wax crystal modification properties in one type of diesel fuel. The block copolymers were tested as neat additives and in formulation with commercial nucleators and growth arrestors in the Cold Filter Plugging Point (CFPP) test to assess performance and to indicate mode of action. The mode of action was then investigated further by observing the effect of the additives on the crystallisation events using DSC. The performance in CFPP and the observations in DSC are consistent with the block copolymers generally acting as nucleating agents, though some also display single-shot activity. There is an observable trend in performance with the varying size of the polar block as well as varying the polar block itself. Chapter 6 Details the experimental procedures used to carry out the work in this thesis.

This work contributes to the development of electrocatalysts for use in polymer electrolyte fuel cells, specifically for the cathodic oxygen reduction reaction (ORR). To achieve this, electrochemical analysis was conducted using biofabricated platinum (bio-Pt) catalyst. Bio-Pt per se was found to be a poor catalyst for the ORR, attributed to the platinum being inaccessible to the reactants. Various ‘cleaning’ techniques were tested to partially remove biomass, providing improved catalytic activity.

This thesis seeks to expand the knowledge on fluid gels and hydrocolloid tribology from a microstructural perspective. This was based on recent research highlighting the significance of tribology for in-mouth fat-related textural analysis during oral processing and the use of hydrocolloids, including fluid gels, for the development of reduced fat liquid and semi-solid foods. This thesis considers the control of fluid gel microstructures and the influence of hydrocolloid microstructure on material properties and lubrication. It is shown that the microstructure of a fluid between two-rubbing surfaces determines the tribological response which cannot necessarily be predicted from that fluid’s rheology. The microstructure of foods is therefore important in determining textural attributes, and tribology is an important field to study alongside rheology for the designed formulation of low-fat foods with acceptable mouth-feel. Particles of kappa-carrageenan fluid gels are shown to form aggregated percolated networks at low volume fractions and to have rheological properties between that typical for linear-polymers and hard-spheres. This behaviour is suggested to result from the particles having ‘hairy’ structures, that is, disordered polymer chains, resultant from a disruption of the molecular ordering process caused by the applied shear during their formation.

The relationship between the formulation of ceramic mould materials for investment casting and their mechanical properties was investigated. A number of different ceramic materials were employed throughout the investigation including alumina, zirconia, mullite and colloidal silica. Ceramic shell specimens were investigated by measuring mechanical strength using flexural and compressive testing with the former being conducted at both room and elevated temperatures. Samples were further investigated by thermal expansion measurement and Archimedes porosity measurement. It was determined that the incorporation of unstabilised zirconia as both a stucco and filler material was effective in terms of reducing the fired strength of investment casting ceramics. Structural observations of samples under SEM revealed that the weakened samples featured significant cracking in the fired condition due to the occurrence of the zirconia phase transition. Thermal expansion measurements confirmed both the presence of the phase transition and the extent of the disruption caused. It was observed for slurries containing silica and alumina, that variation of the proportions of either had a significant effect on the properties of the final shell material. It was also shown that the size of the ceramic particles within the slurry had a significant effect on the final properties of the ceramic body.

This thesis aimed to quantify the effect of anabolic agents ascorbic acid (AA)/ proline (P) on the rates of contraction of the fibrin hydrogel scaffold as well as develop a process for increasing construct collagen content, tensile strength and widths. Supplementation with AA/ P, in combination or individually, revealed contrasting effects on the rates of fibrin gel contraction dependent on concentration and culture duration. There appeared to be strong correlations between the extents of contraction and construct collagen content. Enhancing the stiffness of the fibrin hydrogel augmented widths of the constructs but did not improve construct collagen content or tensile strength. The results further demonstrated that increasing the volume fraction of fibrin fibres present, either by increasing the total volume of reagents or by adjusting the ratio of thrombin to fibrinogen used could be utilised to modify sinew widths. Constructs prepared using a stiffer fibrin gel formulation, supplemented with AA+P, resulted in enhanced collagen content, sinew tensile strength and improved interface tensile attachment. The results also demonstrated variation in fibrin gel contraction rates and collagen production due to different cell sources, growth medium employed or the use of metal ion cofactors Zn\(^{2+}\)/ Mn\(^{2+}\), thereby suggesting areas that could be investigated further and optimized.

In heterogeneous catalysis, a fundamental understanding of the necessary physico-chemical requirements for a catalyst formulation is essential to its success. Understanding of reaction kinetics via modelling can demonstrate how catalysts work, providing functional information around surface active sites and reaction mechanism. This tool, combined with well-designed laboratory experiments to test a catalyst under steady and/or non-steady state conditions, can provide insight into the links between catalyst formulation and reaction performance. The aim of this project is to develop novel strategies and methods in these areas utilising a range of Johnson Matthey catalysts and reaction systems. This thesis places significant focus on obtaining mechanistically and statistically sound kinetic models with reliable model parameter estimates. Methods for this are developed using a batch liquid phase hydrogenation system using a Pt/TiO2 catalyst. Subsequently, non-steady state analysis of catalyst formulations has been explored. This includes the initial transient behaviour of a fresh vanadium phosphorus oxide selective oxidation catalyst under reaction conditions which allowed understanding of the evolution of distinct active site populations on the catalyst surface. A subsequent study of copper-based methanol synthesis catalysts explored the impact of gas phase conditions on the catalyst state. A mixture of steady-state testing and transient response experiments (i.e. via an imposed change in gas phase conditions over the catalyst) provided new insights into the evolution of active site populations and populations of surface species on the catalyst surface. Overall, the reaction kinetics studies demonstrated across this thesis demonstrate not only a series of methods to understand catalyst behaviour in depth but also to understand the key functional requirements for an effective industrial catalyst.