This thesis is an investigation of the photophysical processes that occur in organic photovoltaic blends in the time between light being absorbed and free charges being generated. The purpose of all solar cells is to generate a photocurrent. The free charges, as they flow out of the device, make up the photocurrent, so understanding the processes by which they are created is vitally important to organic photovoltaic research. The main experimental method used was time-resolved fluorescence spectroscopy. This technique was used to probe the exciton population with respect to time for a variety of blends of organic semiconductors, including the high performance photovoltaic materials PCDTBT, PTB7, C71-PCBM and P3HT. The main goal of the work was to characterise the exciton diffusion lengths of these materials by developing a technique called volume quenching. Volume quenching involves blending a small quantity of quenching material into a thin film of semiconducting material. These introduced quenching sites render excitons unemissive on contact. Thus, from the drop in fluorescence compared with the ‘unquenched' material, it was possible to work out what proportion of the initial excitons have encountered a quenching site in the blends. The results can then be fitted to quantify how diffusive the excitons are -i.e. how far they move. By looking at the rate constant of the quenching process and how it varies with respect to time, quencher concentration and quencher type, it was possible to generate a wealth of additional information, not just about exciton diffusion, but about all the inter-related processes that contribute to exciton harvesting. These processes included the measurement of long-range energy transfer from the donor to the acceptor, electron transfer at the interface with the acceptor and the understanding of nanomorphology of donor-acceptor heterojunctions.

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The shortage of water in Mexico has made public and private institutions look at reservoirs as an alternative solution for present and future water supply. However, eighty percent of the existing reservoirs in Mexico are contaminated at some level, many severely. Water quality models are water-management tools used to diagnose water quality problems and the impact of various environmental conditions. They can be effective in assessing various measures of remediation leading to improved water quality. In most of the cases such water quality models have been successfully applied in reservoirs located in temperate climates. However, the use of water quality models in subtropical reservoirs, especially those in developing countries, have relatively little application because either basic data are not available or because they are not sufficient. In this study, a preliminary water quality model was developed for a subtropical reservoir to assess both the ability to collect adequate data and the model's underlying applicability in a subtropical region. The Aguamilpa reservoir is located in the western part of Mexico (Nayarit). It was built for power generation, irrigation and as a fishery. CE-QUAL-W2 is a two-dimensional hydrodynamic and water quality model suitable for long and narrow water bodies. Geometrically the Aguamilpa reservoir is long and deep, making it an ideal candidate to be modeled by CE-QUAL-W2. The model was developed for 1995 and 1996 because of a wider availability of historical data during this period. In addition to a preliminary model and assessment of applicability in this subtropical region, a monitoring and data acquisition plan was designed to identify the minimum required data which must be used to update, calibrate and simulate the water quality parameters. Once the model is calibrated, it may be used to simulate the water quality changes occurring with respect to environmental, climatological and anthropogenic effects. Further, the model may be used to prescribe operating procedures upstream as well as at the dam which can serve to improve the overall water quality. The development of the model at Aguamilpa can serve as a guideline for developing similar water quality models in this and other similar subtropical locations.

This dissertation examines key areas in ontology through the intersection of metaphysics and physics. I argue that modern physics gives us good cause to look for new metaphysical models in place of the classical conceptions of ‘object' and ‘space'. Part I addresses the object in itself, wherein I argue that physics, along with various philosophical concerns, encourages us to re-evaluate the intrinsic/ extrinsic distinction in favour of new classifications. In particular, I use conclusions of relativity theory and the acquisition of mass via the Higgs field as indications of the inadequacy of intrinsicality, concluding that the distinction is more trouble than it is worth. Part II examines the intersection of objects and space, wherein I criticise substantivalism and promote singular fundamental ontologies like relationalism and supersubstantivalism. I examine phenomena like spatial expansion and field theory as well as separability issues more generally to emphasise the lack of rationale for a substance dualism of ‘object material' and ‘space material'. I also challenge the coherence of substantivalism's ‘occupation relation' and the ease of interpreting mathematical models into physical terms. I conclude that, again, the classical notion of ‘object' and its substantival framework are misplaced and should be put aside in favour of developing monistic ontologies. Part III looks at space in itself and the properties commonly attributed to it. I explore issues of separability using key experiments, and what makes spaces ‘physically real', before an extended examination of dimensions and dimensionality, highlighting the confusion physicists express toward such a ubiquitous concept in modern physical theories. I also explore how we use dimensions and reasons for adopting realist or instrumentalist approaches toward them, arguing that much more work should be focused on this area. I conclude with ways in which physics motivates new metaphysical models and suggest improvements for future methodological partnerships.

A series of Pt(S₂N₂)(P(OR)[subscript n]R′[subscript(3-n)])₂ complexes were prepared and analysed using ³¹P NMR and IR spectroscopy, elemental analysis and X-ray crystallography. Similarly, a series of Pt(SeSN₂)(P(OR)[subscript n]R′[subscript(3-n)])₂ complexes were also prepared and analysed. The ¹J[subscript(Pt-P)] coupling constants and Pt-P bond lengths for these complexes are influenced by the oxygen content of their phosphorus ligands. The ³¹P NMR spectra for a series of [Pt(S3N)(P(OR)[subscript n]R′[subscript(3-n)])₂][BF₄] complexes are also reported. Planar [S₂N₂H]⁻ complexes were prepared and the X-ray crystal structure of [Pd(S₂N₂H)(bipy)][Cl] is reported. The X-ray structures of MX₂(P(OR)[subscript n]R′[subscript(3-n)])₂ are reported and compared with the previously reported analogues. The magnitude of the ¹J[subscript(Pt-P)] varies linearly with the Pt-P bond length (l[subscript(Pt-P)] = 2.421 – J/24255) for the 12 platinum-containing complexes. This correlation is compared to that of a larger series of complexes. A series of M(ndsdsd₂ (ndsdsd = bis[(nitrilo(diphenyl)-λ⁶-sulfanyl)](diphenyl)-λ⁶-sulfanediimide (Ph₂S(=N-(Ph₂)S≡N)₂)) complexes were prepared and characterised using elemental analysis and multinuclear NMR and IR spectroscopy where appropriate. The X-ray crystal structures of five examples are reported.

This thesis presents studies of organic semiconductor lasers, including their operation when pumped by a light-emitting diode (LED), and their application as explosive sensors. The photophysics and amplified spontaneous emission (ASE) of star-shaped oligofluorene truxene molecules were investigated. These materials exhibit high gain and low optical loss in thin-film waveguides. Low ASE thresholds were achieved with the truxene T3 and T4. Second-order distributed feedback (DFB) lasers were fabricated, with pump threshold intensities below 0.5 kW/cm² and broad tunability of the emission. DFB lasers were demonstrated with a novel polymer BBEHP-PPV, pumped by a pulsed commercial InGaN LED. The laser emission occurred at 533 nm for peak drive current above 15 A. The output beams and pulse-dynamics of the lasers were investigated for the first time, along with a 'double-threshold' phenomenon that was observed in this long-pulse pumping regime. BBEHP-PPV lasers based on various types of diffractive resonators were also fabricated by UV nanoimprint-lithography (NIL). By optimising the resonator design and the fabrication, and the pump-beam geometry, polymer laser thresholds of ~60 W/cm², the lowest recorded for NIL lasers, were demonstrated, enabling them to be pumped by pulsed commercial LEDs and custom micro-LED arrays. One promising application of organic lasers is in explosive sensing. A polymer of intrinsic microporosity (PIM-1) was used to detect nitroaromatic vapours. Rapid detection of dinitrobenzene (DNB) of low vapour pressure was achieved by monitoring the photoluminescence and laser emission during exposure. In addition, a CMOS time-resolved fluorescence lifetime microsystem with a commercial green-emitting copolymer was used as a novel, portable sensor to detect DNB vapour. An InGaN LED pumped BBEHP-PPV laser was also used as a miniature sensor to detect 10 ppb of DNB. These highly sensitive hybrid sensors could be used in humanitarian demining, complementing existing technologies leading to improvement in the detection of hazardous objects.

During the American Civil War Wilmington, North Carolina and the Bermudian ports of St. Georges and Hamilton served as vital links in a complex trading network that developed to facilitate the exchange of southern agricultural products for war materials and civilian merchandise through a Union blockade of the Confederacy. Although that material contributed significantly to the Confederate war effort, Anglo-Confederate blockade running has received limited scholarly attention. Much of the associated literature is based on memoirs rather than scholarship and does not accurately, reflect that necessarily clandestine trade. The primary goal of this thesis is to produce a more comprehensive and detailed picture of blockade running, the cargoes carried through the Union blockade and the powerful steam vessels that made Anglo-Confederate commerce possible. Unlike previous treatments, this thesis combines the results of both archival and archaeological research. The results illustrate the evolution of strategies involved in both establishing and maintaining the blockade and those developed for running the blockade. Assessment of the vessel remains and historical data associated with the construction and procurement of steamers identifies the vessel types and confirms that blockade runners adapted extant technology. Contrary to the popularly held impression, no technological innovations were specifically developed to address the demands of the trade. The spatial distribution of wrecks and the minimal amount of cultural material surviving in association with them, provides strong evidence that cargoes were more valuable than the vessels. That premise influenced the strategy adopted by blockade runners. While Confederate salvors left little evidence of cargo, historical research revealed a wealth of new insight into the specific nature of that material. This new evidence provides a more accurate and detailed picture of Anglo- Confederate blockade running and the strategies, ships and cargoes that made blockade running between Wilmington and Bermuda a success.

This thesis examines the types of creation imagery used in the Psalms, looking at the historical and cultural influences that affected the Old Testament concepts encapsulated in this Psalmody, and at how traditional creation hymnody has incorporated and modified these concepts. The first chapter examines creation psalmody and argues that there is an overall inclusiveness to be found in such Psalms, where God is viewed as working through the whole of creation and that such Psalms are generally less anthropocentric than some other Biblical texts. This immanent approach is particularly evident through the Old Testament concept of Creator Spirit. Creation hymns are discussed in the three chapters that follow, focusing firstly on hymns of seed-time and harvest, secondly on hymns of the Holy Spirit, and thirdly on hymns with a christological perspective that deal with the main Christian Festivals around Christmas and Easter. In examining rogation-tide hymns and May Day carols, the seedtime and harvest chapter finds many similarities to the images used in creation psalmody, as well as imagery from the old traditional May Day festivals which pre-date Christianity in Britain but which contain a similar kind of natural spirituality to the Old Testament concepts of Creator Spirit. The Harvest Festival hymns, on the other hand, tend to take a more anthropocentric approach, but nevertheless do contain some of the immanent approaches from the Old Testament, in particular the Hebrew Harvest Festival. Chapter 3 examines hymns of the Holy Spirit, and I argue that it is in these hymns that we can find a more fully developed immanent type of theology. Chapter 4 looks at the christological perspectives to the natural world to be found in traditional hymnody, examining in more detail the areas of transcendence and immanence and the implications of the inevitable anthropocentric viewpoint to be found in these texts. I argue in this chapter that it is possible to take a wider and more contemporary theological interpretation of this type of hymnody, and that by doing this we find these hymns amenable to a more inclusive approach to creation as a whole. The thesis concludes by considering the implications of this analysis for worship in the twenty first century.

Attentional set-shifting tasks, consisting of multiple stages of discrimination learning, have been widely used in animals and humans to investigate behavioural flexibility. However, there are several learning criteria (e.g., 6-correct-choice-in-a-row, or 10-out- of-12-correct) by which a subject might be judged to have learned a discrimination. Furthermore, the currently frequentist approach does not provide a detailed analysis of individual performance. In this PhD study, a large set of archival data of rats performing a 7-stage intra-dimensional/extra-dimensional (ID/ED) attentional set- shifting task was analysed, using a novel Bayesian analytical approach, to estimate each rat's learning processes over its trials within the task. The analysis showed that the Bayesian learning criterion may be an appropriate alternative to the frequentist n- correct-in-a-row criterion for studying performance. The individual analysis of rats' behaviour using the Bayesian model also suggested that the rats responded according to a number of irrelevant spatial and perceptual information sources before the correct stimulus-reward association was established. The efficacy of the Bayesian analysis of individual subjects' behaviour and the appropriateness of the Bayesian learning criterion were also supported by the analysis of simulated data in which the behavioural choices in the task were generated by known rules. Additionally, the efficacy was also supported by analysis of human behaviour during an analogous human 7-stage attentional set-shifting task, where participants' detailed learning processes were collected based on their trial-by-trial oral report. Further, an extended Bayesian approach, which considers the effects of feedback (correct vs incorrect) after each response in the task, can even help infer whether individual human participants have formed an attentional set, which is crucial when applying the set-shifting task to an evaluation of cognitive flexibility. Overall, this study demonstrates that the Bayesian approach can yield additional information not available to the conventional frequentist approach. Future work could include refining the rat Bayesian model and the development of an adaptive trial design.

Verification of applicability of the CE-QUAL-W2 model for simulation of phytoplankton, epiphyton and macrophyte growth in Lipno Reservoir was tested. The model was first calibrated for the year 2004, then was applicated to the whole investigated period from 1.1. 2000 to 31.12. 2005. Sensitivity analysis was executed for mean growth parameters of phytoplankton, periphyton and macrophytes.