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360° media experiences have existed for centuries. Viewing painted panoramas, such as those displayed in the 18th-century rotunda in Leicester Square, was a popular Georgian pastime. Recent advances in capture, processing and display technology have created a surge of interest in the medium, with millions of people now viewing captured 360° media immersively. Despite the popularity of 360° media experiences, there are still substantial technical issues associated with production and distribution, and little research has been done that explores the end-user experience. As these experiences become commonplace, understanding the impact of such media becomes critical. In this work, two user studies were conducted that investigated the effects of 360° media of different forms. The first study looked at the impact of the display type when viewing cinematic virtual reality captured as 360° video. The study used three display types: a head-mounted display (HMD); a standard 16:9 TV; and a focus-plus-context display. Several metrics were explored, including spatial awareness, memory and narrative engagement. The second study investigated the impact of different transition types when exploring static scenes captured as multi-view 360° images in a HMD. The three transitions investigated were a linear movement through a 3D model of the scene, an instantaneous teleportation, and an image-based warp using Möbius transformations. Metrics investigated included spatial awareness, preference, and several subjective qualities such as the feeling of moving through the space. Additionally, an enabling technology for such experiences was investigated. Object removal in 360° images was explored in detail, with extensions for video described for simple cases. Taken together, these three projects further our current understanding of how 360° media can be implemented, and examine some of the most critical aspects of how users engage with these experiences.

The North West Company, a Montreal based fur trading corporation, dominated by Scots, developed a commercial operation that between 1779 and 1821 extended to the Atlantic and Pacific axes of the British Empire. The enterprise emerged at a critical juncture in the development of Empire. It was a period of colossal growth and partial dismemberment as well as one of redefinition. Adapting Atlantic and trans-oceanic perspectives this dissertation examines the socio-entrepreneurial networks forged by the North West Company as it sought to expand its commercial reach to encompass Montreal, Quebec, London, New York, Calcutta, Bombay and Canton in a hitherto unexplored form of global economy. To date Imperial and fur trade studies have viewed the fur trade within the confines of a British North Atlantic triangle. This historiographical tendency towards a geographically limited concept of the trade has been exacerbated by the perceived political and economic dislocations brought about by the loss of the American colonies in 1783. The dissertation revises historical orthodoxies to reveal the scale and scope of the fur trade as a pan-imperial activity. Exploring the Company's multi-layered networks highlights not only how the merchants integrated their operation into the Anglo-American Atlantic and beyond but also demonstrates how the Empire actually operated, bringing together its maritime and continental spheres. Identifying the origin, character and evolution of their business practices and linkages modifies conceptions of an increasingly centralised imperial economy of the late eighteenth and early nineteenth centuries. Merchants negotiated between competing and at times overlapping tensions on a local, provincial, imperial and global level as they traversed a plurality of political, cultural and legal frameworks. The manner in which the fur traders co-ordinated and structured their organisation in response to these tensions further challenges the idea of an uncomplicated metropolitan control to reveal the existence of a negotiated imperialism. Placing the North West Company in a broad context allows for a critical and meaningful revision of key geographic, economic, political and chronological disjunctures within the historiography of this crucial phase of Britain's Empire.

This study aimed to investigate any difference between the attributions parents made about their child’s sleep problem, in parents of children with an Autism Spectrum Disorder and parents of children with Down Syndrome. Seventy-six parents of children with an Autism Spectrum Disorder and fifty-two parents of children with Down Syndrome completed a series of questionnaires on-line, regarding their child’s sleep problem, their beliefs about their child’s sleep problem and the parent’s level of anxiety and depression. A significant difference was found between the groups on four of the causal items; other health problem, child’s emotional state, child’s personality and diet. Parents of children with Down Syndrome showed a higher level of agreement that their child’s sleep problem could be attributed to another health problem compared to parents of children with an Autism Spectrum Disorder. Parents of children with an Autism Spectrum Disorder showed a higher level of agreement that their child’s sleep problem could be attributed to their child’s personality, their child’s emotional state and their child’s diet compared to parents of children with DS. There was a high level of agreement across all parents that their child’s disability was a causal factor to their sleep problem and differences in attributions may reflect characteristics of the child’s diagnosis. The results are consistent with previous findings that parents view disability as an important causal factor to their child’s sleep problem and suggest a possible overlap in parent’s views of their child’s sleep problem and views of their disability.

Our aim is to transfer many of the foundational results from the modular representation theory of finite groups to the wider context of profinite groups. We are thus interested in profinite modules over the completed group algebra k[[G]] of a profinite group G, where kc is a finite field of characteristic p. Our approach is as follows. We define the concept of relative projectivity for a profinite module over k[[G]] and prove a characterization analogous to the finite case with additions of interest to the pro and sources for indecomposable finitely generated k[[G]]-modules, extending several results known to hold in the finite case. For sources this requires additional assumptions. We prove a direct analogue of Green's Indecomposability Theorem for finitely generated modules over a virtually pro-p group, as well as a lesser known variant due to M.E. Harris. We give a version of the Green Correspondence for finitely generated modules over virtually pro-p groups.

Colorectal cancer is one of the most common forms of cancers worldwide and the second most common cause of cancer death in the European Union. Surgical resection of the tumour is the primary choice of treatment as it is the only option that offers a chance of permanent cure. However, approximately half the patients who undergo apparently curative surgery will die within five years. It has been shown that up to 30% of patients undergoing apparently curative surgery for colorectal cancer harbour occult liver metastases at the time of presentation and it is the presence of these hepatic metastases that determines the likelihood of death from disseminated disease. The liver possesses a dual blood supply, approximately 75% of the blood coming from the portal vein and 25% from the hepatic artery in the normal subject. There is evidence that these proportions are altered shortly after metastatic seeding in the liver. Previous investigations using Doppler ultrasonography have shown that hepatic arterial blood flow is increased in the presence of liver metastases, while some studies suggest that portal venous blood flow is reduced. The Doppler Perfusion Index (DPI), defined as the ratio of hepatic arterial to total liver blood flow, increases as a result of both these changes. An elevated DPI at the time of apparently curative surgery has been shown to be highly predictive of subsequent recurrence in the liver. It is not known, however, whether the DPI is the most effective index for quantifying the tumour-induced changes in liver blood flow. There is also only limited evidence on whether the primary colorectal tumour alters liver blood flow. To address these questions, hepatic arterial and portal venous blood flow were measured in a series of patients with colorectal liver metastases and normal control subjects. There was no significant difference in either component of liver blood flow between metastases patients with and without a primary or recurrent colorectal tumour. This confirms previous reports that the presence of a synchronous primary does not affect metastases driven blood flow changes. Hepatic arterial flow was increased in patients with liver metastases relative to controls, and portal venous flow was reduced. However, the latter difference was attributable to age mismatching, as portal venous blood flow was found to decline significantly with increasing age. An optimised index, the Dual Flow Index (DFI), was developed by logistic regression analysis to distinguish between metastases and control patients on the basis of the blood flow measurements. This was found to only marginally improve on the DPI in accuracy of discrimination (84% vs. 82% after age adjustment of blood flow). It was concluded that the DPI was close to optimal as a diagnostic index, but that the age-dependence of blood flow should be considered in clinical practice. Doppler ultrasonography is recognised to be an operator-dependent technique, and this may account for conflicting reports in the literature about the blood flow changes associated with liver metastases. It has been suggested that functional Computed Tomography (CT) may provide equivalent information about liver blood flow in a less operator-dependent manner. However, reports on the effectiveness of functional computed tomography in detecting liver metastases are conflicting. Dual-phase contrast-enhanced spiral CT scans were used to assess the varying parameters of tumour-induced changes in liver blood flow. Abdominal scans were performed in patients with liver metastases, colorectal cancer patients without overt metastatic disease, and patients with small benign hepatic haemangiomas. No significant differences were found between these patient groups after adjustment for age imbalances. It was concluded that too many variables affect CT parameters in the routine clinical scanning procedure employed in this and other reported studies for them to be useful for studying blood flow changes. Further work is required in this area using a disease-free normal control population, however Doppler ultrasound currently remains the method of choice for the non-invasive assessment of splanchnic blood flow.

Abstract: In Nova Scotia (NS), within their first year of professional practice newly graduated registered nurses are considered Entry Level Nurses (ELN) (NSCN, 2013, 2020). Until now, little was known about how ELNs experience interprofessional collaboration (IPC) in interprofessional (IP) teams in Nova Scotia. This Interpretive Descriptive (ID) study sought to advance nursing knowledge and greater understanding of ELN experiences. The overarching research question guiding this study was: what are the experiences of ELNs in relation to IPC in IP teams in Nova Scotia? Subsumed under this overarching question was a set of subsidiary questions that reflected the inquiry and analysis required to develop a more comprehensive understanding of IPC across ELN and aggregate perspectives. Fifteen participants were interviewed and thematic analysis (Braun & Clarke, 2006) was conducted. Four main themes surfaced from the interview data. They are described as: (1) emotions linked to IPC, (2) team characteristics, (3) development of IPC competency, and (4) contextual influences on IPC. Several sub-themes were noticed and are discussed in this paper. As Nova Scotia continues to overcome the COVID 19 pandemic, the experiences shared by the participants highlight the importance of further discovery and research. More studies are needed to explore the extent to which these themes are prevalent in healthcare teams. Today’s healthcare milieu of multiple care providers and complex treatment regimens demand the active participation from nurses and all members of the interprofessional (IP) team including the patient and family (Accreditation Canada, 2019). Interprofessional collaboration (IPC) is an essential component in the delivery of nursing care. The State of the World’s Nursing 2020 report (WHO, 2020) proclaims the healthcare system needs RNs working to the full extent of their education and the maximization of their roles within IP teams (WHO, 2020). Similarly, the Nova Scotia College of Nursing (NSCN, 2020) defines the RN as a collaborator required for optimal IPC. New trends and issues are documented in nursing (ICN, 2020; WHO, 2020). The World Health Organization (2020) suggests that newly graduated registered nurses play a key role in resolving nurse burnout, current workload issues, and recruitment and retention challenges. The COVID 19 pandemic has highlighted the urgent need to address these issues in nursing, especially from the viewpoint of ELNs in unpredictable team circumstances while attempting to achieve IPC.

The spin state of the nitrogen-vacancy (NV) center in diamond offers a promising platform for the development of quantum technologies and investigations into spin dynamics at the nanoscale. With a lengthy coherence time even at room temperature, NV centers enable precision metrology with atomic scale spatial resolution and present one path towards quantum information in the solid state. These applications require coherent control of the NV center spin state, and this can be achieved with resonant magnetic fields, electric fields, or, at cryogenic temperatures, optical fields. In this thesis, we demonstrate direct mechanical control of NV center spins by coherently driving magnetically-forbidden spin transitions with the resonant lattice strain generated by a mechanical resonator. We then employ mechanical driving to perform continuous dynamical decoupling and extend the inhomogeneous dephasing time of a single NV center spin. Finally, we demonstrate and quantify a spin-strain coupling within the NV center room temperature orbital excited state and propose a dissipative protocol to cool a mechanical resonator mode using this interaction. The methods of mechanical spin control developed here unlock a new degree of freedom within the NV center Hamiltonian that may enable new sensing modes and could provide a route to NV center-mechanical resonator hybrid quantum systems.

As partial fulfillment of a doctoral degree in Educational Leadership, a retrospective, multi-element study was performed. The study compared the Incremental Rehearsal method (IR) and the Pocket Word method (PW) to each other and to Repeated Reading (within Instructional Level [RR-IL] by individually teaching words from the Dolch Word List to first-grade students. The effects of IR, PW, and RR-IL on the word retention, reading accuracy, words read per minute, passage retell, and aided comprehension of seven first-grade students were compared. The Peabody Picture Vocabulary Test (4th edition) and the Dolch Word List were administered prior to intervention. The three conditions were administered at a rate of a single intervention every 24 hours (Monday, Tuesday, Wednesday, and Thursday) in order to counterbalance the intervention effects. Word retention, reading accuracy, and words read per minute were assessed at 24 hours and 7 days after each condition. Reliability of the administration was assessed by a school psychologist. The findings demonstrate an increase in the total number of words retained from pre-measure to post-measure on the Dolch Word List for each individual student and across all students. A visual analysis of individual cumulative data showed an increase for each student, an increase for all students, and confirmed the differentiation of conditions between the IR and PW method from the RR-IL method. As such, positive effects were found for the IR and PW methods for word retention at 1 and 7 days for each student and across students. The IR method demonstrated differentiation from PW and RR-IL for words read correctly in text. Limitations, observations, and recommendations for further study are discussed.

Bivalent drug design is an efficient strategy for increasing potency and selectivity of many drugs. We devised a strategy to prepare agonist-benzodiazepine heterodimers that could simultaneously bind to agonist and BZD sites of the GABAAR. We synthesized a benzodiazepine-MPEG model compound that relied on physiological GABA to elicit flux. We established that a tether at the N1 position of the BZD would not prevent binding to the receptor. However, coupling of GABA amides with long chain PEG tethers studied by another group member resulted in complete loss of agonist activity. We therefore ceased research in this particular area. 1,4-Benzodiazepin-2,5-diones display a wide range of pharmacological activities. Compounds containing the tricyclic proline-derived subtype have received attention as potent anxiolytic agents and as starting materials for anthramycin-inspired anticancer agents. More recently enantiopure (S)-proline-derived 1,4-benzodiazepin-2,5-diones have been recognized as selective α5 GABAA receptor ligands. Despite the impressive diversity of 1,4-benzodiazepine-2,5-diones prepared to date, enantiopure examples possessing a quaternary stereogenic center have been largely unexplored. "Memory of chirality" (MOC) is an emerging strategy for asymmetric synthesis. This technique enables the memory of a sole chiral center in the substrate to be retained in a process that destroys that center. We have used this technique to prepare a library of quaternary proline-derived, thioproline-derived and hydroxyproline-derived 1,4-benzodiazepin-2,5-diones, in high ee. We have developed an efficient synthetic method for preparing oxaproline-derived 1,4-benzodiazepin-2,5-diones in high yields, and by applying the MOC strategy we have prepared quaternary derivatives in acceptable %ee. We envision oxaproline-derived 1,4-benzodiazepin-2,5-diones may exhibit similar or more potent pharmacological properties than proline-derived 1,4-benzodiazepin-2,5-diones. Using density functional theory (DFT) methods, we modeled the formation of an enantiopure, dynamically chiral enolate intermediate and the slow racemization of the enolate on the alkylation reaction time scale.

The upland hardwood component of Prince Edward Island's Acadian forest is among the best remaining examples of PEI's pre-colonial landscape, but there has been no assessment of the presence of exotic species in these areas. Three 300 metre long edge to interior transects were established in each of six Acadian forest study areas. Nine 100 m2 circular plots were sampled along each transect at distances from 5.7 to 300 metres; one external plot was established at each transect to sample species in adjacent (non forest) habitats. In each plot, all vascular plants were identified, a visual estimate of percent cover was made, and soil temperature, canopy cover and tree diameters were measured. The results show that there is an edge-to-interior plant community gradient within these forests, and suggest that interior conditions are not reached until a distance of more than 120 metres from an edge. (Abstract shortened by UMI.).

The thesis describes a research project with group of year 8 girls in a secondary school in the North West of England. The project was developed in response to a gap in early intervention and preventative approaches in schools for children and young people presenting with persistent difficulties in relationships with peers and adults at school. These difficulties are suggested as distal risk factors associated with child sexual exploitation (CSE) The research is pragmatic, combining mixed methods data within a case study design. Following the identification of early possible risk factors for CSE, 4 girls in year 8 were selected along with two positive peer role models to take part in weekly group sessions using cognitive behaviour approaches (CBA) to address social problem-solving, self-efficacy, relatedness and social support networks. The aim of the study was to evaluate an early intervention using CBA, to consider the outcomes of the intervention and the aspects of the CBA the girls perceived to be most useful. The results mainly derive from a thematic analysis of data from semi-structured interviews conducted with each participant at the beginning, middle and after the completion of the sessions. In addition, supplementary data was gathered using the Resiliency Scales for Children & Adolescents (Prince-Embury, 2007), Target Monitoring Evaluations (Dunsmuir, 2006) and cognitive behavioural approaches (CBA) rating scales. The analysis of all the data sources indicated that the group CBA was successful in supporting better social problem-solving skills, self-efficacy, relatedness and social support networks. This varied according to the needs of the participant. The results suggest that improvements in social problem-solving, self-efficacy, relatedness and social support networks were supported by the use of the four systems model of response (FSMOR) CBA technique (Greenberger and Padesky, 1995). This live problem-solving technique was effective when applied in a group context where all the participants were female including two positive role-models. Participants applied the FSMOR in combination with taught assertive communication techniques. In addition, clear evidence of cognitive behaviour therapy principles applied in practice, seemed to support the progress made by the participants. The benefits of a group setting for delivering FSMOR is suggested because of the alternative cognitions that were validated by peers within the safe and secure group context. The study has implications for the design and delivery of interventions aimed at meeting the needs of vulnerable girls in secondary schools. This includes acknowledging the importance and influence of peer relationships for girls and the benefits of addressing the issues related to social problem-solving with peers through group CBA in order to reduce unhelpful behaviour. The study relies solely on data provided by the participants. To address this limitation, future studies could include additional data from key school staff concerning the participantâ€ÂÂTMs presentation in the skill areas targeted in the intervention. In addition, gathering information from key staff about participant school engagement would also further support the link between social problem-solving, self-efficacy, relatedness, social support networks and better school engagement.

Microwave thermal treatment has generated an increasing interest in biomass valorisation. In this research, softwood, hardwood and straw are processed by microwave-assisted acidolysis, producing high quality residual lignin without significant modification, especially softwood (purity 93%, yield 82%). Under equivalent conditions, microwave treatment produces lignin with higher yield and purity than conventional treatment. The aqueous hydrolysate is fermented by two oleaginous yeasts, Cryptococcus curvatus and Metschnikowia pulcherrima. Both yeasts could grow on the hydrolysate and produce an oil with similar properties to palm oil. This preliminary work demonstrates new protocols of microwave-assisted acidolysis and therefore offers an effective approach to produce high purity lignin and fermentable chemicals, which is a key step towards developing a zero-waste lignocellulosic biorefinery. In addition, microwave conversions (lab and pilot scale) of bilberry presscake, aiming to fulfill multiple chemicals recovery, were carried out using only water as the solvent, ensuring all products are suitable for food grade status applications. Microwave hydrolysis gives much higher yield of mono-/disaccharides than conventional extraction, with the yield of rhamnose particularly high (10.8%). Pilot scale microwave conversions are also carried out with high conversion. It is believed microwave hydrolysis offers an efficient and green approach to convert bilberry presscake into value-added products for food industry and biorefinery.

The synthesis, characterisation, and catalytic applications of a range of novel iron-N-heterocyclic carbenes (Fe-NHCs) immobilised on renewable resources (expanded high amylose corn starch 4a, StarbonTM 350 4b, StarbonTM 400 4c, mango peel cellulose 4d and orange peel cellulose 4e) are reported. The efficacy of the resultant heterogeneous catalysts was measured for their ability to convert: fructose to 5-(hydroxymethyl) furfural (HMF); glucose to HMF and glucose to 5-(chloromethyl)furfural (CMF). The immobilised catalysts were prepared using a convergent strategy starting from the appropriate renewable resource, e.g., (4a-e) and 1-(3-aminopropyl) imidazole (7) to afford the precursor nitrogen heterocyclic carbene, e.g., (13a-e), which was treated with FeCl3 to furnish the desired Fe-NHC, e.g., (1a-e). Iron-loadings of 0.68 mmol g-1 for (1a), 0.31 mmol g-1 for (1b), 0.32 mmol g-1 for (1c), 0.30 mmol g-1 for (1d) and 0.52 mmol g-1 for (1e) were achieved. At 100oC and varying reaction time (10 min, 20 min, 0.5 h, 1 h, 3 h and 6 h), all catalyst types showed good performance for the dehydration of fructose to HMF: Fe-NHC expanded HACS (1a), HMF yield 86 % (t=0.5 h), TOF=206 h-1; Fe-NHC StarbonTM 350 (1b), HMF yield 81.7 % (t=0.5 h), TOF=169 h-1; Fe-NHC StarbonTM 400 (1c), HMF yield 81.0 % (t=0.35 h), TOF= 241 h-1; Fe-NHC MPC (1d), HMF yield 70.0 % (t=1 h), TOF= 79.2 h-1; Fe-NHC OPC (1e), HMF yield 71.7 % (t=0.5 h), TOF= 146 h-1. The catalysts showed very good recycling stabilities up to 5 catalytic cycles. The fabricated catalysts were also employed in other catalytic application in important reactions including glucose dehydration to HMF, and gluose/fructose dehydration to CMF. The supported catalysts slightly effect CMF production from glucose and fructose but were ineffective towards amidation reactions of carboxylic acids and amines (as higlighted in future work).

The capability of measuring surface temperatures of hybrid circuits at the Virginia Tech Hybrid Microelectronics Laboratory has been established. This capability provides a quantitative method for effectively evaluating thermal design software. Surface operating temperatures were measured and predicted for an operating hybrid circuit. The temperatures were measured using an infrared thermal imaging system, which measures surface temperatures by detecting the infrared radiation emitted and reflected. The accuracy of the measurements has been quantified for variations in surface emissivity, convective cooling condition, and operating temperature range. The most accurate temperature measurement of a one-resistor circuit was compared to the operating temperature predicted by a lumped-parameter one-dimensional heat transfer analysis. The comparison agreed within the expected limits for this simple analysis and identified areas for possible improvement both of the model and the experimental technique. Thermal design of a circuit is critical because excessive temperatures are a common cause of circuit failure. Circuit designers rely on computer programs to predict circuit component temperatures because of the high cost of prototype experimentation. Accurate thermal design software that is currently available is too complicated for occasional use by circuit designers. Simple, yet accurate, thermal design software is essential for this type of design, so that circuit layouts can be quickly and easily optimized.

Background: Peer Group Supervision (PGS) is based on the belief that there are no intended power relationships as the members of PGS are generally of equal status and they rotate roles and decide how PGS will be structured (Inskipp, 1996). The planned PGS meetings are leaderless, egalitarian in principle and comprise of practitioners who work in similar fields (Kadushin & Harkness, 2002). PGS members can draw upon each other's experiences, gain advice on difficult cases and issues (Askhurst & Kelly, 2006; Davys & Beddoe, 2010; Kaiser & Barrettta-Herman, 1999) and develop a wide range of skill-based knowledge (Proctor, 2010). PGS has been found to be an effective form of peer support to a wide range of professionals. Limited research exists regarding PGS within an Educational Psychology Service (EPS) context. The aim of this research study is to employ a Realistic Evaluation (RE) framework to evaluate PGS within an EPS. Participants: An EPS provided the context of the research study. The sample of participants reflected the composition of the EPS: four full-time equivalent main grade Educational Psychologists (EPs), one main grade EP 0.4, one Senior EP and the Principal Educational Psychologist (PEP). All participants were actively sought and recruited through purposive sampling (Thomas, 2009). Methods: I adopted a RE framework (Pawson & Tilley, 1997) as the methodological approach. RE is a theory-driven approach to evaluate social programmes (Pawson & Tilley, 1997). RE aims to identify causal mechanisms and the conditions under which they are activated to produce specific outcomes. The realist formula is symbolised as Context (C) + Mechanism (M) = Outcome (O), (CMO). Semi-structured interviews and a focus group were the main means of collecting the qualitative data. Thematic analysis coding described by Braun & Clarke, (2006) was used to analyse the data. Analysis/Findings: Semi-structured interviews and a focus group were thematically analysed following full transcription (Braun and Clarke, 2006). Global themes were organised and structured under a realist CMO formula. Based on the methodology employed, the findings reveal contextual and mechanism themes to support the use of PGS within an EPS. The key mechanisms within PGS were: team dynamics, commitment and protected time. The key contexts were: social conditions, the PGS model and structure. The key outcomes were coded into educative, supportive and managerial (self-monitoring) functions (Hawkins & Shohet, 2006). EPs reported that PGS was valued, it had a sense of purpose and overall it provided a forum to foster positive engagement and affinity with peers (Marks & Hixon, 1986; Christensen & Kline, 2001). PGS was highlighted as organic because other EPS interest/research groups developed plus there was a growing interest from schools and other settings in PGS led by EPs. One disenabling mechanism noted to be hampering the implementation of PGS included EPs contending with competing priorities such as, extra workload and time pressures. This resulted in EPs missing PGS sessions. Conclusion/Implications: This thesis contributes to the limited amount of literature on the study of PGS within the field of educational psychology. This study gives a greater insight into the use of PGS within an EPS context. PGS has become embedded into policy and practice within the EPS. Additionally, as other teams and school practitioners have become aware of PGS, the demand for PGS training has increased and has become part of the traded elements of the psychological service delivery.

Due to the recent trends to improve fuel economy and reduce emissions there have been changes to engine design, resulting in higher temperatures and more nitrogen dioxide in the engine, as well as increased biodiesel usage. Overall, this has led to a more severe environment for the engine lubricant, increasing degradation; an understanding of the mechanism is required to prevent this degradation. Squalane has been used as a model base oil and degraded in an environment of nitrogen dioxide at 150 oC. GC x GC has been used to separate the resultant product mixture, and time of flight mass spectrometry identified products as the squalane alcohol, ketones and alkane fragments. Nitrogen containing products have been identified using a GC x GC with nitrogen chemiluminescence detector, the highest concentration of product has been identified as nitromethane. Other nitroalkanes have been proposed based on retention index. The experiments have been repeated for mixtures of nitrogen dioxide and oxygen and no unique products have been identified. The impact of biodiesel degradation has been assessed using methyl linolate as a model compound and applying the same techniques as used for the base oil model system. The products have been identified as being due to fragmentation of the methyl linolate and the formation of ketones. The largest nitrogen containing product concentration being the nitromethane, other nitoalkanes which have been identified. This experimental evidence has led to the elucidation of the mechanism for nitration which is presented and compared with the autoxidation mechanism. The nitration is hydrogen abstraction initiated by NO2. The second stage is the addition of NO2 to form an alkyl nitrite. The CO-NO bond is comparable to a peroxide, therefore decays to an alkoxy radical. The alkoxy radical can then follow the established mechanisms in autoxidation to form the observed products.

Currently, antioxidants used in biodiesel to prevent degradation by autoxidation are synthesized from petroleum, which is non-renewable and has had a volatile price in recent years. Therefore, this thesis examines the possibility of using phenolic species from bio-oils derived from woodchips as antioxidants to protect biodiesel. Crude bio-oil (18.5% w/w of woodchips) was obtained by microwave-enhanced pyrolysis of spruce woodchips (picea abies). Characterization by multiple analytical techniques shows that a noticeable portion of the bio-oil consisted of aromatics (mostly phenols) and sugars. The phenolic content of the bio-oil was quantified and identified by GC-FID & GC-MS and was found to be ca. 6% (w/w), while the total phenolic content was determined by Folin-Ciocalteu (FC) assay was ca. 23% (w/w). To isolate these phenols, the crude bio-oil was further fractionated by supercritical CO2, and by two multi-solvent fractionation methods, namely: water-insoluble phase and water-soluble phase. The extract obtained with the highest phenolic content was a diethyl ether extract isolated from the water-soluble phase of crude bio-oil, at ca. 56% (w/w) by FC assay, with ca. 9% (w/w) identified and quantified by GC-MS & FID. The effectiveness of these renewable phenols in a model biodiesel was examined using methyl linoleate autoxidation in 1 bar of oxygen at 120 ○C. Addition of low amounts of crude bio-oil to methyl linoleate was sufficient to increase its induction time, and was comparable with a commercial antioxidant (butylated hydroxy-toluene). Further examination of methyl linoleate with bio-oil isolated extracts indicated that these were less effective than the parent crude bio-oil. This was striking because some of the isolated extracts contained higher phenolic concentrations than the bio-oil. The antioxidancy of a chemical model of the crude bio-oil phenol consisting of six representative components at appropriate concentrations was approximately three times less active than the crude bio-oil, suggesting that components with noticeable antioxidancy remain to be identified.

Described in this thesis is work based on silica and palladium catalysis which focusses on the formation of amide-containing compounds. Efforts were made towards expanding the substrate scope of direct amide bond formation reactions catalysed by an activated K60 silica catalyst. Two of the resulting amides were then investigated as substrates in single and oxidative C–H functionalisation reactions to form phenanthridin-6(5H)-ones.

The biorefinery is an important concept for the development of alternative routes to a range of interesting and important materials from renewable resources. It ensures that the resources are used fully and that all parts of them are valorized. The project will develop this concept, using macroalgae Ascophyllum nodosum as an example. The project focuses on valuable chemicals (e.g. fucoidan, alginate and sugars) and fuels (bioethanol and biochar) from macroalgae by assistance of microwave technology. Microwave assisted extraction of fucoidan proves that fucoidan could be extracted in 5-30 min by microwave heating from 90 oC to 150 oC, and the highest yield (16.08%) was obtained at 120 oC, 15 min. The compositional characterization of fucoidan was carried out, and antioxidant activity test shows that fucoidan could potentially be a resource for natural antioxidant. Microwave assisted extraction of alginate proves that alginate could be extracted successfully under low temperature (60-90 oC) - open vessel system and high temperature (100-140 oC) - closed vessel system, respectively. The results show that high temperature extraction had higher yield in less time compared with low temperature extraction, and Mw from both extraction were similar, 180 kDa – 220 KDa. Microwave assisted hydrolysis of Ascophyllum nodosum shows that the optimal condition for saccharification was 0.4 M H2SO4, 3.13% (w/v) of biomass loading, reaction temperature at 150 oC for 1 min holding time, resulting in 127 mg/g monosaccharides of seaweed being released. An ethanol concentration of 5.57 g/L and a conversion efficiency of 60.7% were achieved after fermentation. More than 50% energy yield of alga residue was recovered after hydrolysis, and the energy densification ranged from 1.4 to 1.7, with HHVs from about 19 - 24 MJ/kg. In addition, a step-by-step extraction and purification method was developed, in which fucoidan, alginate, sugar and biochar could be separated subsequently.

The aim of this project was to develop new route to silica and silica based materials through utilizing green techniques and demonstrate its following applications. Due to the properties of supercritical fluids including high diffusivity, low dynamic viscosity and low surface tension, supercritical fluid (SCF) is becoming a potential alternative solvent class in materials chemistry. The physical properties of SCF could be tuned to more liquid- or more gas- like thus providing an enhanced selectivity of the solubility performance of SCF. Several conditions such as reaction time, pressure and temperature were have been taken into consideration for the synthesis of a spherical mesoporous silica using supercritical carbon dioxide as solvent. Bio-oil has successfully been utilized to prepare carbon-silica composites (CSCs) from mesoporous silicas. These CSCs comprise a thin film of carbon dispersed over the silica matrix and exhibit porosity similar to parent silica with BET surface areas ranging from 39 to 636 m2/g and pore volumes ranging from 0.03 to 0.31 cm3/g. The surface properties of resulting materials can be simply tuned by the variation of preparation temperatures leading to a continuum of functionalities ranging from polar hydroxyl rich surfaces to carbonaceous aromatic surfaces. The as-synthesised CSC was subsequently used as solid support for the deposition of palladium nanoparticles to catalyse the Heck reaction. This CSC catalyst exhibited a high catalytic activity and excellent reusability for the Heck reaction using either conventional solvent NMP or propylene carbonate. It should be noted that a side product - methyl 3,3-diphenylacrylate was generated during the reaction using CSC catalyst in propylene carbonate with the yield of up to 15.5%. The CSCs were also used to prepare carbonaceous materials by silica etching process. After silica removal, a mesoporous carbonaceous material with the morphology ranging from rod-like to tubular-like could be synthesised.

There is a rising global demand for energy and growing concerns about greenhouse gas emissions. Lignocellulosic biomass offers great potential for second generation bioethanol production, based on the biorefinery philosophy. It is composed of a network of interconnected polymers cellulose, hemicellulose and lignin which has evolved to develop recalcitrance against enzyme hydrolysis produced by microorganisms in nature. Therefore, pretreatment is necessary to make the biomass structure more accessible for enzyme to hydrolysis. The aim of this thesis is to demonstrate the potential of using microwave to assist thermo-chemical pretreatment for lignocellulosic biomass, namely Miscanthus, sugarcane bagasse and maize. The pretreatment process was influenced by pretreatment temperature, pretreatment media and holding time. 0.2 M -1 M H2SO4 and NaOH were used as preteatment media. Firstly, temperature optimisation was carried on Miscanthus and the results showed that 180 oC was the optimal temperature to efficiently release monosaccharides from biomass. In comparison with classic conventional heating pretreatment, microwave assisted pretreatments maximally released 12.5 times more reducing sugars during the pretreatment process. Secondly, the reducing sugar constitutions were tuned by change holding time or pretreatment media, because hemicellulose was easier to be broken down than cellulose. Xylose and glucose were selectively produced by using NaOH and H2SO4 (or FeCl3) respectively as pretreatment media. Chemical compositions and biomass morphological changes were investigated and compared. The significant removal of hemicellulose and lignin, as well as more dismantled fibre structure led to enhanced bioethanol conversion via SSF process (simultaneous saccharification fermentation). Similar study was conducted on sugarcane bagasse and maize. The performance of pretreatment media was similar. However, their optimal conditions for reducing sugar release were different, probably due to different chemical compositions percentages and biomass structure. Overall, in comparison with conventional heating pretreatment, microwave assisted pretreatment is much energy efficient and effective, showing promising potential in the biorefinery process.

The overall objective of this thesis was to develop an enhanced understanding of the sulfonation of Starbons® and the properties of the sulfonated materials, using conventional and microwave heating. Starbons® are materials prepared from expanded starch. Due to their renewable nature, these materials are great candidates to be explored in our search for sustainable development. The sulfonated Starbons® (S-Starbons®) were tested as solid-acid catalysts in esterification reactions using microwave irradiation. A green chemistry analysis of some current routes to sulfonated carbonaceous materials is presented in Chapter 1. Here, an in-depth description of Starbons® is also given, as a brief review of some techniques used in their characterisation. Synthesis and characterisation of S-Starbons® by conventional heating and microwave irradiation are presented in Chapter 2 and Chapter 3, respectively. Elemental composition of Starbons® depends on carbonization temperature, changing from high-oxygenated (300 °C) to more carbon-like (800 °C) materials. After sulfonation, the sulfur content varies with carbonization temperature, being particular high for the most-oxygenated samples. All S-Starbons® present a characteristic IR band ca. 1030 cm-1 independently of sulfonation method. 13C solid-state NMR gives structural information from S-Starbons®, however, due to overlapping resonances it was difficult to identify the C–S resonance. XPS showed that sulfur (VI) is the only one observed in S-Starbons® 300, but sulfur (II) appears in higher temperature carbonized Starbons®. The main difference between microwave and conventional sulfonated Starbons® 300, was the appearance of another sulfur (VI) species in the microwaved samples. Chapter 4 relates to the stability of the sulfur-bonding in S-Starbons®,through TG-FTIR analysis. This study suggests that stability of the sulfur bonding is higher in S-Starbon® 300 than in S-Starbon® 800. This observation was correlated with the catalytic performance of these materials (Chapter 5), where S-Starbon® 800 loses its activity more rapidly than S-Starbon® 300.

Scrutiny over solvent selection in the chemical industry has risen in recent decades, popularising research into neoteric solvent systems such as ionic liquids and supercritical fluids. More recently bio-based solvent products have been considered as replacements for conventional petroleum derived solvents. Because they bear a close resemblance to existing solvent products, bio-based solvents can be readily absorbed into the fine chemical industries. This work develops a methodology for identifying reactions of concern with respect to current solvent selection practice, and then implementing a high performance bio-based solvent substitute. In this thesis, kinetic studies of heteroatom alkylation, amidation, and esterification are documented, and the solvent effect dictating the rate of each reaction ascertained. With the ideal properties for the solvent known, bio-based solvent candidates were screened for suitability in each case study. This process, which employs computational tools, was also applied to model the productivity of the Biginelli reaction as a representative multi-component heterocycle synthesis. A strong case is made for limonene and p-cymene as bio-based solvents for all but heteroatom alkylation from the case studies listed above. Alkylations with nitrogen nucleophiles are instead suited to high polarity solvents, and to this end some bio-based amides were investigated.

The objectives of this project were to synthesise zeolites and aluminosilicate materials from silicon sources derived from biomass ashes. These materials will have great potential as catalysts and adsorbents. In order to begin this study it was necessary to find and optimise a technique for extraction of silicon to an alkali silicate solution from biomass ashes. It was then necessary to develop a technique for analysis of the alkali silicate solutions. This was done using calibration of integrals from infrared spectra. An optimisation of the synthesis of Zeolite X from a rice hull ash derived alkali silicate was developed and these materials were analysed and characterised using XRD, N2 Adsorption porosimetry, X‐Ray Fluorescence Spectroscopy, and X‐Ray Photoelectron Spectroscopy. An in‐depth study of the surface of the ash derived and reference Zeolite X was undertaken using in situ small molecule probing FT‐IR. It was found that although the materials were similar there was a significant difference due to the presence of a strongly bonded carbonate species in the pores of the bio‐derived zeolite. Synthesis of a Miscanthus ash derived mesoporous silica, MCM‐41, was successfully achieved which was comparable to its conventionally synthesised equivalent. Both displayed ordered hexagonal pores and high surface areas. A study on addition of different sources of aluminium found that it was possible to introduce aluminium into the structure successfully. Included in this study was the addition of the waste product ‘red clay’ as an aluminium source. Another mesoporous silica, SBA‐15 was synthesised from a Miscanthus ash derived alkali silicate. It was necessary to optimise the synthesis to adapt to the different pH systems of the conventional method and bio‐derived alkali silicate solutions. This was achieved and a bio‐derived SBA‐15 material with ordered hexagonal pores was produced.

Automotive engines contain aggressive environments where lubricants are degraded by exposure to corrosive combustion by-products such as nitrogen oxides (NO2 and NO), and understanding their interaction is key to the development of long-lived lubricants. Therefore the effect of 1000 ppm of nitrogen oxides on lubricants containing phenolic and aminic antioxidants, individually or in combination, in branched alkane base fluid has been investigated in laboratory reactors at 180 °C, representative of piston conditions. The reaction of the phenolic antioxidant, octadecyl 3-(3,5-di-tert-butyl-4-hydroxy-phenyl) propanoate with 1000 ppm NO2 in N2 resulted in the formation of a quinone methide product (octadecyl3-(3,5-di-tert-butyl-4-oxo-cyclohexa-2,5-dien-1-ylidene)propanoate), in apparent contradiction to previous studies, which observed at room temperature the formation of nitro-phenols. Therefore a novel reaction mechanism is proposed to account for this change in mechanism with the temperature, with the addition of NO2 to phenoxyl radicals being dominant at low temperatures, but reversible at a higher temperature,at which the dominant reaction becomes an abstraction of a hydrogen atom from the α carbon on the alkyl group at the para- position of the phenoxyl radical. The thermochemistry of key intermediates for this mechanism was also investigated using ab-initio calculation, allowing the prediction of the ceiling temperature for the addition of NO2 (1000 ppm) to phenoxyl radicals, and hence of the formation of nitrated phenolics, to be approximately 51 ± 57 °C. The reaction of the aminic antioxidant, 4.4’-dioctyl diphenylamine, with 1000 ppm NO2 was also investigated, with chemical analysis of the reaction products showing the formation of two monomers and five dimers of the starting antioxidant, and possible reaction mechanisms are based on these results. The reaction of NO2 with phenolic and aminic antioxidants when used in conjunction resulted in the identification of two new intermediates formed partially from fragments of aminic and phenolic antioxidants; novel chemical mechanisms for their formation are also suggested.

Commercially available inorganic solids and organically functionalised silicas and silica-polysaccharide composite materials synthesised in the laboratory were characterised by various techniques. These included direct infrared spectroscopic measurements, infrared and UV-visible probing techniques using probe molecules such as water, ammonia, d3-actonitrile, aniline, Reichardt’s dye and iodine and also by the application of the Knoevenagel condensation as a model reaction. As well as the information obtained about the surface activity of the solids, this review of techniques revealed the advantages and limitations of well-known and less frequently used methods. In particular, the use of iodine as a UV-visible probe molecule allowed the observation of differences between materials that are extremely difficult to analyse such as sodium carbonate and sodium acetate. However with current levels of knowledge about the electronic transitions of iodine adsorbed on surfaces, the results are not straight forward to interpret. The silica-polysaccharide composites also showed interesting properties, both in terms of their morphology and their chemistry and merit further study.