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This thesis represents the cumulation of an industrially based project (KTP 10134) to find resource within manufacturing waste and develop a circular economy within industry. This work documents this collaborative project between Lancaster University's Chemistry and Engineering departments and an industrial partner (Crown Paints), highlighting specific milestones and outcomes of the project which may be of interest to wider industry and academia. The manufacture of aqueous based paint (also known as emulsion, water based or latex paint) produces large volumes of waste, the largest stream by far is industrial effluent (estimated at Crown Paints alone to be approx. 30,000,000 l annually); produced primarily from the washing of production vessels. Crown Paints is a leading UK based decorative paint manufacturer and part of the global Hempel Group. Crown Paints operates two production sites situated in Hull and Darwen, UK. The Hull site produces much more aqueous-based product and produces a larger volume of effluent waste (16,000 m3, 2015). Currently, this effluent is pre-treated at each of the two sites' effluent plants, which flocculate any particulates producing an inert filtercake, which is currently sent for disposal in landfill. To fully assess the paint manufacturing process, from a waste generation perspective a simple Value Stream Analysis (VSA) of the process was performed. This uses an already established Lean Six Sigma tool (i.e., VSA), which was applied from a unique wastewater perspective. Thus, a novel environmental application of VSA for establishing the origin of excessive water useage in industrial processes is presented. Laboratory based modelling (via jar testing) of the current coagulation and flocculation based effluent process and subsequent plant trials suggested an ability to reduce the consumable useage of flocculant by 50%. To improve the laboratory testing further and to focus on the filtration aspect of the process a novel automated stepped pressure filtration method was developed. This included an innovative design of a filtration apparatus and a new method to further characterise the process of filtration. The data interpretation method presented applies a multi-step systematic approach, with each step supported by statistical justification, to characterise filter cake particle stress, filtration diffusivity and cake hydraulic resistivity from a single stepped pressure experiment. Experimentally this new method showed no impact of the 50% flocculant reduction on the filtration parameters of interest. Additionally, it was also shown that the raw effluent could be utilised as the "solvent" within the paint production process with limited effect on the paint's physical properties. From laboratory testing this was scaled to production volumes (circa. 9,000-19,000 l) and a method was developed to reduce virgin raw materials by up to 5%. A production batch (9,000 l) with 4% extra product (360 l) was produced. Testing of this trial batch showed no difference with a standardised paint formulation. This presents an exciting opportunity for water reuse within various Fast Moving Consumer Goods (FMCG) manufacturing processes.

This thesis details work with two topological materials, Sb2Te3 and RhPb2, with the overall aim of identifying and optimising novel materials candidates for the next generations of computational technologies. Single crystals of Topological Insulator Sb2Te3 are synthesised, using excess Te in a melt growth to suppress the formation of point defects in the crystal and tune the electrical properties. The magnetotransport is characterised using a multiple-band transport model, where novel quantum oscillations are also resolved from non-trivial Dirac states in the bulk of the material. Topological Superconductor candidate RhPb2 is synthesized using DC sputtering and an annealing protocol, producing single phase, textured, superconducting thin films for the first time. The electronic and superconducting properties of the system are established, and signatures of conventional phonon-mediated spin-singlet superconductivity are resolved.

Thermal treatment of the UK's intermediate level nuclear waste, such as vitrification, offers significant long-term storage savings compared to cementation. However, concerns exist surrounding the volatility of components present in intermediate level waste streams that must be addressed for thermal treatment to be a viable immobilisation option. Of particular interest are caesium radioisotopes, which account for a large proportion of the radioactivity in intermediate level waste. This thesis aims to assess the volatility of caesium species during vitrification using a bespoke laboratory apparatus, allowing for in-situ assessment of the volatile species produced. This information can be fed back into the glass formulation to minimise/eliminate volatility during vitrification. A bespoke, in-situ off-gas capture and analysis system has been designed and commissioned to enable this work, briefly comprising of a gas tight stainless steel system, a fibre coupled Raman spectrometer, connected to the steel apparatus using a quartz window Raman flow cell and gas washing bottles to allow for the analysis of off-gas solutions to aid a caesium mass balance. To aid the identification of caesium bearing volatiles produced during the glass melts, trials were conducted in the system described above using caesium carbonate, caesium borate, and a mixed alkali borate. The purpose of these trials was to collect reference spectra of known volatile caesium species in the same experimental apparatus as the glass melts were to be conducted in. Two glass series were designed to facilitate this work, an iron phosphate series and a sodium borosilicate series. Alkali borosilicate glasses are the most commonly used glass type for the immobilisation of high activity nuclear waste, in this work, the influence of additives (CaO and ZnO) on caesium retention during the vitrification process were investigated. The results presented in this thesis feed into the wider body of research conducted on the effect of CaO and ZnO on glass structure, which in turn influences important properties such as chemical durability and wastestream solubility. Iron phosphate glasses were selected for this study as a promising candidate for UK wastestreams that are poorly suited to borosilicate glasses. Both glass types were thoroughly analysed before being re-melted with varying caesium oxide waste loadings in the system described above. The iron phosphate glass series investigated three additives, B2O3, MnO and ZnO. Each of the additives were substituted into a 40Fe2O3-60P2O5 iron phosphate system in place of Fe2O3. The main aim of studying a range of additives at varying concentration was to investigate their effect on caesium retention, however each additive was expected to influence the glass system in a different way. B2O3 was selected to investigate the relationship between B2O3 and caesium volatility at varying B2O3 concentrations, as the existence of caesium borate species above glass melts has been demonstrated in the literature. MnO was selected to investigate the relationship between the iron oxidation state and caesium retention, as Mn was expected to form a redox couple with the Fe present in the glass system. Finally, ZnO was selected as studies conducted on borosilicate glass systems have shown ZnO to have a positive influence on caesium retention and this study aimed to investigate if the same effect would be observed in an iron phosphate glass system. It was found that B2O3 and ZnO additions improve caesium retention, whilst MnO additions showed minimal improvement when compared to the 40Fe2O3-60P2O5 system. All glasses with additive concentrations of less than 7.5 mol% crystallised during the caesium doped remelt, with B2O3 melts crystallising regardless of the additive concentration. Glasses containing 7.5 and 10 mol% MnO or ZnO remained amorphous after the caesium doped remelt with Raman spectroscopy of the bulk glass indicating no significant structural changes. The sodium borosilicate system investigated the influence of ZnO on caesium volatility, using a modified version of the UK'S CaZn composition, which is currently used to immobilise high level waste in the UK. Glasses with varying Zn:Ca ratios (100:0 to 20:80) were produced and remelted at Cs2O waste loadings of 2, 5, and 10 wt.%. A correlation was found between the measured Zn:Ca ratio and caesium retention. Glasses with low ZnO concentrations performed worse than the glasses with higher ZnO concentration. However, the NaBSZn100Ca0 composition did not perform as well as glasses containing CaO. Off-gas Raman analysis of the caesium vapours showed that at Cs2O loadings of 5 and 10 wt.%, a mixed alkali borate (NaCs(BO2)2) species was the dominant volatile identified. At the 2 wt.% Cs2O loading, the off-gas Raman spectra indicated that a caesium borate species was dominant. Importantly, this work showed that off-gas Raman spectroscopy can be used to detect differences in caesium volatiles during thermal treatments such as vitrification. Overall, the NaBS series performed better than the IPG series in terms of caesium retention. However, it would be useful for further studies to compare the two glass systems at similar viscosities rather than arbitrary melting temperatures.

The ability to accurately model complex biological processes such as protein-ligand binding with an atomistic level of detail is critical to their thorough understanding. Typically a molecular mechanics simulation is used, which represents the system using a force eld that is a physically motivated linear combination of empirically parameterised potentials. Traditionally their parameterisation has involved the recreation of experimental and quantum mechanical data for a target set of representative structures, ranging from small molecules to peptides. This potentially limits the progress of general transferable force elds to time and labour-intensive incremental improvements. In this thesis, we aim to challenge this \parameterise once and transfer" philosophy, with that of a transferable parametrisation methodology that can be readily applied to new systems with a consistent level of accuracy. We collect together recently developed force eld parameterisation techniques from the literature to develop a protocol suitable to derive virtually all required force eld parameters for small molecules directly from quantum mechanics. This protocol forms the basis of the QUantum mechanical BEspoke force eld (QUBE) and is delivered to users through a reliable and extensible software toolkit named QUBEKit. Here we extensively benchmark the methodology and software presented through typical force eld performance metrics which involve the prediction of thermodynamical properties of small organic molecules. In this regard, we achieve very competitive accuracy with popular general transferable force elds such as OPLS which have been extensively optimised to reproduce such properties. We also demonstrate how the QUBE force eld is a suitable alternative in a computer-aided drug design setting via the retrospective calculation of the relative binding free energies of 17 inhibitors of p38 MAP kinase. Again good agreement with both experiment and transferable force elds is achieved despite this being the rst generation of the force eld. The results of this work are then particularly important to those studying systems which are not covered or inaccurately represented by standard transferable force elds, as we present an accurate framework towards their complete parameterisation.

The treatment performance of small WWTPs (< 250 PE) in England is not well understood and their ecological impact may be underestimated. However, the critical role such systems play in ensuring sustainable wastewater management, means they can no longer be neglected. The aim of this thesis, therefore, was to provide new data, understanding and analytical approaches to improve the management of existing, small WWTPs. Firstly, through an extensive sampling campaign, we found a significant difference (p < 0.05) between the effluent quality discharged from twelve small and three larger WWTPs across a range of abiotic parameters. Specifically, mean removal rates at the small plants were 67.3 ± 20.4%, 80 ± 33.9% and 55.5 ± 30.4% for sCOD, TSS and NH4-N (± standard deviation), respectively, whereas equivalent rates for larger plants were 73.3 ± 17.6%, 91.7 ± 4.6% and 92.9 ± 3.7%. A Random Forest classification model accurately predicted the likelihood of a small WWTP becoming unreliable. Among the important predictors was population equivalence, suggesting the smallest WWTPs may require particularly stringent management. Quantifying, in the raw and treated wastewater samples, three genetic faecal markers targeting Bacteroides and two targeting E. coli, revealed that humanassociated Bacteroides markers have the greatest potential as alternative performance metrics at small WWTPs, however, all markers were influenced by seasonality. Next, the problem of predicting flows at small scales was overcome using an inverse approach to solve a linear reservoir function (NSE = 0.77 – 0.93). The model was combined with the field data to generate pollutant loads and investigate the effect of influent peak loading of COD on the final effluent quality at small discharges. Simple tools developed, here, provide wastewater managers with new techniques to improve the operation and increase the understanding of small WWTPs. Growing awareness of the need for sustainable wastewater and water resources management makes the work both timely and of global relevance.

Anecdotally, females with autism present differently from males. However, studies into autism tend to use a predominantly male sample, and make few gender-based comparisons. Hence, there is relatively little research on gender-specific presentations of autism. Furthermore, those studies that have been undertaken are equivocal in their findings. Should males and females with autism present differently, then the male preponderance in the research population may lead to a bias in our understanding of autism, and the diagnostic criteria it informs, creating circularity. This thesis aimed to investigate if and how females with autism present differently, while avoiding the problem of circularity. As diagnostic criteria for autism consider behaviour (potentially biased to favour males), the diagnosed samples of participants in studies will present with similar behaviours, regardless of gender. However, gender differences may persist in areas of cognition, such as block design. A literature review of gender differences among people with autism on the block design task revealed only one adequately powered study; this indicated a possible gender difference. To expand the data available, a meta-analysis of studies comparing people with and without autism on the block design task was carried out. Then, the ratio of males and females within autism and control groups was regressed as a proxy indicator of gender differences. This did not reveal any gender differences. An alternative approach was adopted within the research study. Through asking professionals highly experienced in diagnosing autism about gender differences in autism, it was hoped that they would express their own conception of autism, beyond the present diagnostic criteria, thereby avoiding circularity. A thematic analysis of interviews with 14 clinical psychologists with expertise in this area was conducted. Gender differences in presentation, but not underlying pathology, were noted by participants. Trans-diagnostic constructs such as social awareness and motivation were thought to drive the gender differences in presentation. However, although the presentation and constructs were gender biased, they were not gender-specific, suggesting a broader view of autism is needed beyond dichotomous gender differences.

Despite long-standing recognition that the constellation of ethical and political ideas developed by the seventeenth-century Natural Law School played an important part in the development of Enlightenment thought, the relationship between the two remains a fertile area of research in intellectual history. Filling a lacuna in existing scholarship, this thesis contends that central tenets of the ethical and political philosophies developed by the Natural Law School were appropriated by the more liberal and progressive contributors to the Encyclopédie ou Dictionnaire raisonné des Sciences, des Arts et des Métiers (1751-1772); which is frequently considered to be the summa of Enlightenment thought, and emblematic of the conflict between the new ‘philosophical spirit’ and the traditional hierarchies, institutions, and values of the ancien régime. It argues that by establishing the loi naturelle and natural rights of the individual as the foundation of both ethics and politics in many of its articles, the Encyclopédie questions the certainty and validity of Catholicism as the basis for both, and that it therefore played an important role in undermining the moral authority of the Church as well as the political authority of the State. In particular, it asserts that the more liberal and humanitarian contributors to the project put the central tenets of Natural Law thinking into practice, in order to tackle and propose reform of what they perceive to be some of the worst injustices in contemporary society, namely with regard to the related questions of slavery and luxury. For those encyclopédistes who believe in universal rights and the loi naturelle, both the slave trade and the attitude of their contemporaries to luxury seem to embody values very different to those they wanted to promote; in their eyes both are representative of a society in which self-interest and the satisfaction of individual passions are valued over and above any consideration for the needs, welfare, and rights of others.