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Sahaja Yoga: An Ancient Path To Modern Mental Health?, Adam Morgan Jan 1999

Sahaja Yoga: An Ancient Path To Modern Mental Health?, Adam Morgan

School of Psychology Theses

The present study looks to evaluate the effectiveness of the meditative practice of Sahaja Yoga as a treatment for the symptoms of anxiety and depression. Whilst there is a small research literature that has investigated the efficacy of meditation (usually based upon the Buddhist Vipassana tradition) for the treatment of such symptoms, and a smaller literature looking at the effectiveness of Sahaja Yoga in the treatment of a number of physical health problems, no published studies have looked at the effectiveness of Sahaja Yoga as a treatment for mental health problems. The present study therefore compared three independent groups, these …

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An Improved Method For The Large-Scale Processing Of Woad (Isatis Tinctoria) For Possible Commercial Production Of Woad Indigo, Kg Stoker, Dt Cooke, Dj Hill Dec 1998

An Improved Method For The Large-Scale Processing Of Woad (Isatis Tinctoria) For Possible Commercial Production Of Woad Indigo, Kg Stoker, Dt Cooke, Dj Hill

Peninsula Medical School

The increasing use of alternative crops has meant the introduction of new technologies to process their products. In this work, an alternative method is presented for the extraction of natural indigo from woad (Isatis tinctoria) based on a technique used to extract indigo from Indigofera spp. This method does not rely on the old fermentation procedure used throughout Northern Europe and is cheap, clean and efficient. Evolved from laboratory-based tests, it involves steeping the leaves at low pH in warm water and extracting the indigo at a higher pH, followed by ultra-filtration of the product, which is then left to …

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Energy Demand Perspectives In Bangladesh, (1992/93 – 2019/20), S Rahman Jun 1998

Energy Demand Perspectives In Bangladesh, (1992/93 – 2019/20), S Rahman

School of Geography, Earth and Environmental Sciences

The present paper attempted to forecast the demand for primary energy broadly categorized into: (a) commercial (coal, petroleum, natural gas, and hydropower), and (b) non-commercial energy (rice hull and straw, jute stick, firewoods, crop wastes, etc.) for the period 1992/93-2019/20 AD to facilitate in the energy sector planning and development. The demand forecast, based on past time series data (1972/73-1991/92), is made by utilizing two methods: (a) "Market Penetration Theory" that uses trend extrapolation and inter-fuel substitution priniciples, and (b) "Trend Extrapolation Model" taking into account the the exogenous variables, e.g., GDP and energy/GDP ratio. Results reveal that the fractional …

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The Bioavailability Of Sediment Bound Tributyltin (Tbt), Nicholas Dingle Pope Jan 1998

The Bioavailability Of Sediment Bound Tributyltin (Tbt), Nicholas Dingle Pope

School of Biological and Marine Sciences Theses

Tributyltin is arguably the most toxic compound ever to be deliberately introduced into the marine environment as an ingredient of antifouling paints. It has had widespread toxic effects on a range of marine organisms, with some gastropod species being particularly sensitive. Effects of TBT on non-target species have resulted in partial bans on its use in many countries, so that new inputs to the water column have decreased in most areas. One of the physicochemical features of TBT is that it is readily sequestered by suspended particulates due to its low solubility and its hydrophobicity, therefore becoming incorporated into estuarine …

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The Modes Of Action Of Toxicants On The Cardiac Physiology Of The Blue Mussel, Mytilus Edulis, And The Common Shore Crab, Carcinus Maenas, Timothy Mark Curtis Jan 1998

The Modes Of Action Of Toxicants On The Cardiac Physiology Of The Blue Mussel, Mytilus Edulis, And The Common Shore Crab, Carcinus Maenas, Timothy Mark Curtis

School of Biological and Marine Sciences Theses

The primary aim of this thesis was to establish the mode of action of the heavy metal, copper, on the cardiac physiology of the blue mussel, Mytilus edulis. Exposure of specimens of M.edulis to dissolved copper led to a decrease in heart rate and an increase in heart rate variability (HRV). The concentration of copper causing a 50% reduction in heart rate was found to be 0.8µM, while the concentration causing a 50% increase in HRV was 0.06µM (48 h EC50s). Simultaneous measurements of valve activity indicated that the observed bradycardia was not caused by valve closure. Subsequently, it was …

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Evaluation Of Stream Meiofauna As A Monitor Of Trace Metal Contamination, Susan Mary Burton Jan 1998

Evaluation Of Stream Meiofauna As A Monitor Of Trace Metal Contamination, Susan Mary Burton

School of Biological and Marine Sciences Theses

Members of the meiobenthos have been used extensively to determine the effects of anthropogenic perturbation in marine systems (Coull & Chandler, 1992). Despite this, the meiofauna has been virtually excluded from freshwater pollution monitoring. This thesis aimed to address this research caveat, by evaluating the potential of stream meiofauna for monitoring metal-contamination. Meiofaunal communities were sampled from streams in SW England representing a gradient in metal contamination. Environmental variables in these streams were also measured to identify the important forcing agents structuring the stream benthos. Multivariate techniques demonstrated Cu, either alone or in combination with other environmental variables was of …

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Spatio-Temporal Distributions Of Pelagic Larvae And Post-Larvae Of Decapod Crustacea In Seas Around Britain, John Alistair Lindley Jan 1998

Spatio-Temporal Distributions Of Pelagic Larvae And Post-Larvae Of Decapod Crustacea In Seas Around Britain, John Alistair Lindley

School of Biological and Marine Sciences Theses

The geographical distributions and seasonal occurrences of decapod larvae and pelagic post-larvae in continuous plankton recorder (CPR) samples over a 3-year period were analysed and described. During this period, the survey covered large areas of the north-eastern Atlantic Ocean and adjacent continental shelf waters, including the English Channel and the North, Irish and Celtic Seas. Multivariate analysis provided the basis for classifying the distributions of 36 of the most abundant taxa (species, genera or subfamily) into groups. These groupings demonstrated the significance of bathymetry and temperature in limiting distributions. Larvae of 3 species were shown to disperse during development from …

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Physiological And Cellular Level Responses Of Enteromorpha Spp. To Chemical And Thermal Stress, Stella Anne Lewis Jan 1998

Physiological And Cellular Level Responses Of Enteromorpha Spp. To Chemical And Thermal Stress, Stella Anne Lewis

School of Biological and Marine Sciences Theses

The aims of this project were to investigate the cellular stress response (CSR) in Enteromorpha spp. and assess the potential of the Stress-70 protein (an indicator of the CSR) as a biomarker of pollutant exposure and acquired tolerance in Enteromorpha spp., compared with conventional physiological endpoints of toxicity. Cross-reactivity of a commercial Stress-70 antibody with E. intestinalis proteins was determined and used to develop an assay for Stress-70. Using this assay E. intestinalis was found to exhibit a typical heat shock response. Stress-70 proved to be a relatively insensitive biomarker of copper exposure and did not appear to be involved …

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Measurement Of Suspended Sediment Transport Processes Off The Holderness Coast - Southern North Sea, England, Joanna Catherine Blewett Jan 1998

Measurement Of Suspended Sediment Transport Processes Off The Holderness Coast - Southern North Sea, England, Joanna Catherine Blewett

School of Biological and Marine Sciences Theses

A field campaign was set up as part of the LOIS-RACS coastal program (1994-1996), to identify the near-bed physical processes responsible for suspended sediment movement in shallow water (10-20m depth) off the Holdemess coast, NE England. A new benthic tripod system Boundary Layer Intelligent Sensor System (BLISS) has been developed and deployed along a transect at three sites, normal to the coastline at Tunstall. Measurements of current velocity, suspended sediment concentration (SSC), pressure and CTD were recorded at 5 Hz for 17 minutes every hour, on the same data acquisition system. Results are presented for the summer, July 1995 and …

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The Ecotoxicological Assessment Of Complex Effluents Using Invertebrate Biomarkers, Katrina Nicola Astley Jan 1998

The Ecotoxicological Assessment Of Complex Effluents Using Invertebrate Biomarkers, Katrina Nicola Astley

School of Biological and Marine Sciences Theses

A suite of biomarkers was developed using the crab Carcinus maenas and the mussel Mytilus edulis as test organisms. The ability of the biomarkers to differentiate amongst the major toxic components and to indicate the concentration of chemical mixtures was evaluated in the laboratory. Biomarkers were also applied in a field trial and their potential to monitor environmental water quality in a chemically contaminated estuary investigated. The results from the biomarker assays were compared with and validated against two commonly used toxicity tests (Tisbe battagliai LC-50, and Microtox®). Novel methods for recognising patterns of biomarker responses were developed and assessed. …

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Physiological Responses Of Gracilariopsis Longissima To Copper Exposure, James Edward Newman Jan 1998

Physiological Responses Of Gracilariopsis Longissima To Copper Exposure, James Edward Newman

School of Biological and Marine Sciences Theses

Seaweeds fulfil many of the criteria regarded as being important for a good biomonitor. They are known to accumulate trace metals and the concentration of these metals measured in the thalli of native populations has been related to the level of contamination in the surrounding water. However, this passive biomonitoring approach has been of limited use and the relationship between the concentration of metal in the seaweed and that in the surrounding environment is not always apparent. The aim of this study was to investigate the response of the rhodophyte Gracilariopsis longissima to copper exposure, in the laboratory and field, …

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A Soft Systems Approach To The Formulation Of A Manufacturing Strategy, Tammy Jane Greswell Jan 1998

A Soft Systems Approach To The Formulation Of A Manufacturing Strategy, Tammy Jane Greswell

School of Engineering, Computing and Mathematics Theses

This work investigated the understanding and use of current manufacturing strategy methods within the UK aerospace industry. Several key issues were identified which suggested a need to rethink the process of manufacturing strategy formulation. The set of issues included: the lack of explicit manufacturing strategies by several case organisations, a lack of the general use of developed manufacturing strategy tools and techniques, and a general evolution of organisations from functionally based to a business process focus. These issues suggested that the current approaches to manufacturing strategy were not reaching their target audience practitioners, and that further development of the manufacturing …

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Automated Diesel Engine Condition & Performance Monitoring & The Application Of Neural Networks To Fault Diagnosis, Christopher Lloyd Owen Jan 1998

Automated Diesel Engine Condition & Performance Monitoring & The Application Of Neural Networks To Fault Diagnosis, Christopher Lloyd Owen

School of Engineering, Computing and Mathematics Theses

The overall aim of this research was to design, configure and validate a system which was capable of on-line performance monitoring and fault diagnosis of a diesel engine. This thesis details the development and evaluation of a comprehensive engine test facility and automated engine performance monitoring package. Results of a diesel engine fault study were used to ascertain commonly occurring faults and their realistic severities are discussed. The research shows how computer simulation and rig testing can be applied to validate the effects of faults on engine performance and quantify fault severities. A substantial amount of engine test work has …

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Assessment Of Asphalt Materials To Relieve Reflection Cracking Of Highway Surfacings, Michael David Foulkes Jan 1998

Assessment Of Asphalt Materials To Relieve Reflection Cracking Of Highway Surfacings, Michael David Foulkes

School of Engineering, Computing and Mathematics Theses

The thesis investigates the mechanisms and restraints which influence transverse crack propagation through the bituminous surfacings of semi-flexible pavements. These pavements incorporate continuously laid cement bound roadbases which, during curing, crack into slabs of varying length, ranging from 4-25m. Reciprocal crack growth can occur in the surfacing, known as 'reflection cracks', located through stresses concentrated at the discontinuities within the roadbase . Three mechanisms have been identified and are described as contributing to reflection crack propagation. They have been analysed independently although the majority of conclusions drawn are applicable to their combined action. Their relative importance will vary with respect …

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3d Object Recognition Based On Constrained 2d Views, Levente Toth Jan 1998

3d Object Recognition Based On Constrained 2d Views, Levente Toth

School of Engineering, Computing and Mathematics Theses

The aim of the present work was to build a novel 3D object recognition system capable of classifying man-made and natural objects based on single 2D views. The approach to this problem has been one motivated by recent theories on biological vision and multiresolution analysis. The project's objectives were the implementation of a system that is able to deal with simple 3D scenes and constitutes an engineering solution to the problem of 3D object recognition, allowing the proposed recognition system to operate in a practically acceptable time frame. The developed system takes further the work on automatic classification of marine …

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The Balance Between Activation And Inhibition In Stereotype Use, Na Wyer, Dl Hamilton Jan 1998

The Balance Between Activation And Inhibition In Stereotype Use, Na Wyer, Dl Hamilton

School of Psychology

No abstract provided.

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Instigating Change In A Globalised Social Environment : The Impact Of Globalisation Upon The Promotion Of Vegetarianism In The United Kingdom, Andrew David Smart Jan 1998

Instigating Change In A Globalised Social Environment : The Impact Of Globalisation Upon The Promotion Of Vegetarianism In The United Kingdom, Andrew David Smart

School of Law, Humanities and Social Sciences Theses

In this thesis I examine globalisation as an ongoing social change to understand how it is routinely reproduced by social actors. To do this I consider the impacts of globalisation in an existing social setting and use a conceptual framework from the sociological literature to interpret and explain the evidence. The empirical materials were gathered during an ethnographic case study of The Vegetarian Society - an interest group that actively promoted social change by presenting everyday individual food consumption in the manner of reflexive 'life politics'. I use the concepts of 'interpenetration', 'relativisation', 'detraditionalisation' and 'institutional reflexivity' to indicate that …

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Intergroup Bias In Group Judgment Processes: The Role Of Behavioral Memories, Jw Sherman, Sb Klein, A Laskey, Na Wyer Jan 1998

Intergroup Bias In Group Judgment Processes: The Role Of Behavioral Memories, Jw Sherman, Sb Klein, A Laskey, Na Wyer

School of Psychology

Two experiments examined the role of memory for behavioral episodes in judgments about in-groups and out-groups. Using a minimal group paradigm, participants read either positive or negative trait-relevant behaviors performed by group members. They then were asked to make judgments about the group's trait characteristics. Results demonstrated that for groups described positively, judgments about the out-group but not the in-group were accomplished by retrieving from memory specific behaviors performed by group members. In contrast, for groups described negatively, judgments about the in-group but not the out-group were accomplished by retrieving specific behaviors performed by group members. These results suggest that …

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Polycystic Ovary Syndrome Coagulation And Metabolic Studies, William Usinode Atiomo Jan 1998

Polycystic Ovary Syndrome Coagulation And Metabolic Studies, William Usinode Atiomo

Peninsula Medical School Theses

The polycystic ovary syndrome (PCOS) is a heterogeneous disorder in women characterised by chronic ovulatory failure, hyperandrogenaemia, and insulin resistance. Some women are completely asymptomatic and others present with extreme menstrual disturbance, severe hirsutism, infertility and recurrent miscarriage. The pathophysiology of PCOS is not completely understood, but it is thought that insulin resistance plays a central role. In normal subjects, non-diabetic obese patients and patients with non-insulin dependent diabetes, insulin resistance is associated with elevated plasminogen activator inhibitor-1 (PAI-1) levels. PAI-1 is a glycoprotein, which inhibits the formation of plasmin (a proteolytic enzyme). Plasmin aids fibrinolysis and extracellular proteolysis. High …

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Modelling The Prevalence Of Down Syndrome With Applications Of Markov Chain Monte Carlo Methods, Isabelle Cella Bray Jan 1998

Modelling The Prevalence Of Down Syndrome With Applications Of Markov Chain Monte Carlo Methods, Isabelle Cella Bray

School of Engineering, Computing and Mathematics Theses

This thesis was motivated by applications in the epidemiology of Down syndrome and prenatal screening for Down syndrome. Methodological problems arising in these applications include under-ascertainment of cases in livebirth studies, double-sampled data with missing observations and coarsening of data. These issues are considered from a classical perspective using maximum likelihood and from a Bayesian viewpoint employing Markov chain Monte Carlo (MCMC) techniques. Livebirth prevalence studies published in the literature used a variety of data collection methods and many are of uncertain completeness. In two of the nine studies an estimate of the level of under-reporting is available. We present …

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Fluid Inertia And End Effects In Rheometer Flows, Jason Hughes Jan 1998

Fluid Inertia And End Effects In Rheometer Flows, Jason Hughes

School of Engineering, Computing and Mathematics Theses

This thesis is concerned with the characterisation of the flow behaviour of inelastic and viscoelastic fluids in steady shear and oscillatory shear flows on commercially available rheometers. The first part of this thesis is concerned with a linear viscoelastic theory to describe the oscillatory shear flow behaviour of fluids on a Weissenberg rheogoniometer. A fluid inertia perturbation analysis is used to produce analytical formulae for correcting complex viscosity data for first and second order fluid inertia effects. In order to validate the perturbation theory we perform a simulation of the oscillatory shear flow behaviour of Newtonian and single element Maxwell …

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Technological Change And Women’S Participation In Crop Production In Bangladesh, S Rahman, Jk Routray Jan 1998

Technological Change And Women’S Participation In Crop Production In Bangladesh, S Rahman, Jk Routray

School of Geography, Earth and Environmental Sciences

There is a dearth of information on the employment effects of modern agricultural tech nology on rural women in Bangladesh. The present study1 looks at women's participation in crop production activities, examines their influence in the diffusion of modern technol ogy and their participation in the hired labor market. Data for this study comes from two intensive surveys conducted in the crop years 1989 and 1996 in three agro-ecological regions of Bangladesh. Findings suggest that the prevailing claim-that women are involved only in post- harvest processing of crops-underestimates their contribution to agricultural production. Women's share of total labor is 10-18 …

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Plant Ecology And Community Dynamics Of Machair Systems In The Outer Hebrides, Nia Wyn Owen Jan 1998

Plant Ecology And Community Dynamics Of Machair Systems In The Outer Hebrides, Nia Wyn Owen

School of Geography, Earth and Environmental Sciences Theses

The machair systems of the Outer Hebrides of Scotland are renowned for the diversity and conservation value of their plant communities. However, machair systems have a restricted distribution and are prone to disturbance from both anthropogenic and environmental sources. The effects of two major anthropogenic and environmental disturbances (agriculture and burial by wind-blown sand) on the Kildonan and Drimsdale machair systems on South Uist, and the dynamic responses of machair vegetation to these human and natural agencies were described and quantified. The investigated machair systems comprised a diversity of sand dune, grassland and marginal vegetation types which were spatially distributed …

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Landfill Design, Construction And Non-Invasive Monitoring, Amanda Jane Hopper Jan 1998

Landfill Design, Construction And Non-Invasive Monitoring, Amanda Jane Hopper

School of Geography, Earth and Environmental Sciences Theses

Three techniques are investigated in order to assess their applicability for use in landfill design, construction and monitoring. Firstly, an assessment is made of QA procedures during liner construction through the detailed evaluation of two case studies. Construction QA procedures on-site are compared to available guidelines. The research illustrates the requirement for standardised, regulated QA procedures on landfill sites in order to provide a recognised framework for construction control. The Moisture Condition Value Test (MCV) is evaluated for use as a method of monitoring the placement of compacted clay landfill liners. London Clay and Mercia Mudstone, collected from the QA …

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Trace Metal-Particle Water Interactions In The Western North Sea, Joanna Dixon Jan 1998

Trace Metal-Particle Water Interactions In The Western North Sea, Joanna Dixon

School of Geography, Earth and Environmental Sciences Theses

The distribution of trace metals (Fe, Mn, Cu, Cd and Pb) has been determined in dissolved and particulate phases, along with relevant hydrographic parameters, from the nearshore coastal zone of the western North Sea (between 52ON and 56ON) during four Land Ocean Interaction Study (LOIS) surveys covering the seasonal cycle (autumn 1994 to summer 1995) The behaviour of the redox-sensitive metals, Fep and Mnp in the western North Sea were strongly correlated (r>0 44 for all seasons, P<0 05) in all surveys and exhibited maximum concentrations in winter (16 mg g -1 and 700 ug g-1 respectively) which progressively decreased throughout the year Distinct seasonal variations were also observed for particulate Cu, Cd and Pb For example, enhanced concentrations of Cup (36 ± 39 ug g-1) and Cdp (0.36 ± 0.42 ug g -1) in the Humber coastal zone during summer were attributed to preferential particulate organic/biogenic-metal interactions. In contrast enhanced, though diffuse, atmospheric inputs of Pb from continental winds were considered to have contributed to the elevated Pbp concentrations (82 ± 27 ug g -1) observed offshore during winter Results from radiotracer incubation experiments suggest that biological activity makes a significant contribution to the removal of dissolved Mn and Cd to the particulate phase. However, a phase lag of two to three months between maximum primary productivity and maximum particulate metal adsorption (KD=2 X 104 & 5 x 102 for Mn and Cd respectively) indicates a decoupling from the spring plankton bloom In general metal distributions in the Humber coastal zone were significantly influenced by freshwater discharge, tidal regime at the mouth of the estuary and prevailing wind conditions Total trace metal fluxes across the mouth of the Humber Estuary were highest during spring (311, 8 96 & 1045 kg day-1, for Cu, Cd and Pb respectively) and lowest during summer (25 7, 1 .12 & 33 4 kg day-1, for Cu, Cd and Pb respectively) They were dominated by variations in freshwater outflow and the tidal range during sampling On an annual basis comparison to estuarine inputs (rivers, industry and sewage sources) suggested retention of Cu (25%) and Cd (56%) Estimates of partitioning (KD) were derived from the dissolved and particulate data for Cu, Cd and Pb over the seasonal cycle Copper was dominated by the particulate phase (73-80%) in all seasons but summer, whilst Cd showed particulate phase dominance (54-70%) in autumn and winter only The Pb distributions were dominated by the particulate phase (94-99%) independent of season Trace metal settling velocities implied that the Humber Plume was acting as a sink for Cu, Cd and Pb in winter and spring However settling velocities calculated for Cd and Pb (flood tide) in summer were similar to background suspended particulate matter (SPM) suggesting long range transport with the residual circulation. Modelling of Pb isotopic ratios in the Humber Plume suggested that on average 32-39% of the extracted Pbp originated from anthropogenic sources The data from this study has given unique information concerning the concurrent seasonal distributions of particulate trace metals in the western North Sea and have yielded new insights into mechanisms affecting trace metal cycling and transport, essential in the development and refinement of coupled hydrodynamic-geochemical models.

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Development Of A Low Pressure-Inductively Coupled Plasma-Ion Source For Mass Spectrometry, Gavin Thomas O'Connor Jan 1998

Development Of A Low Pressure-Inductively Coupled Plasma-Ion Source For Mass Spectrometry, Gavin Thomas O'Connor

School of Geography, Earth and Environmental Sciences Theses

A low pressure-inductively coupled plasma (LP-ICP) ion source has been investigated for the production of atomic and molecular ions for mass spectrometry (MS). A dedicated LPICP- MS was constructed, by modifying a Hewlett Packard mass selective detector, to detect ions from the LP-ICP. The ion sampling interface and ion optics were designed using established theory and the use of a computer simulation program. Perfluorotributylamine was continuously introduced into the LP-ICP, via a molecular leak, and the ion sampling interface, plasma forward power, and plasma gas flow rates, were optimised. When the LP-ICP ion source was sustained at 6W with a …

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A Hydrological Investigation Of Three Devon Sand Dune Systems; Braunton Burrows, Northam Burrows And Dawlish Warren, Rachel Jane Burden Jan 1998

A Hydrological Investigation Of Three Devon Sand Dune Systems; Braunton Burrows, Northam Burrows And Dawlish Warren, Rachel Jane Burden

School of Geography, Earth and Environmental Sciences Theses

In 1993 concerns were expressed by English Nature that Devon's three largest sand dune systems Braunton Burrows, Northam Burrows and Dawlish Warren were drying out to the detriment of the dune habitat flora and fauna. Research was therefore required to understand how these systems functioned hydrologically, to determine whether they were drying out and if so to recommend sustainable management options aimed at reinstating former water levels, or preventing any further lowering of the water tables. At Braunton water table elevations have been monitored on a monthly basis by the Nature Conservancy, the Nature Conservancy Council and English Nature since …

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Robustness And Precision Of Holocene Palaeoclimatic Records From Peatlands Using Testate Amoebae, Dawn Hendon Jan 1998

Robustness And Precision Of Holocene Palaeoclimatic Records From Peatlands Using Testate Amoebae, Dawn Hendon

School of Geography, Earth and Environmental Sciences Theses

This thesis represents the first attempt to use quantitative testate amoebae (Protozoa: Rhizopoda) analysis to measure hydrological fluctuations in British peatbogs over the Holocene. Changes in the fossil species assemblage are used to reconstruct the mean annual water table records at different locations on mire surfaces using a transfer function designed for application on oligotrophic peatlands. The transfer function was found to provide more precise reconstructions for depth to water table than percentage soil moisture. Multiple cores were extracted from three of the Border Mires; Coom Rigg Moss and Butterburn Flow (both intermediate ombrotrophic bogs) and The Wou (a minerogenic …

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Modelling And Monitoring Of Phosphorus Transport And Speciation In Soil, Darren Michael William Peat Jan 1998

Modelling And Monitoring Of Phosphorus Transport And Speciation In Soil, Darren Michael William Peat

School of Geography, Earth and Environmental Sciences Theses

Flow through soil into groundwater has been classically conceptualised as taking place through a set of aligned capillary tubes. In solute transport models these approximations are also present. Pore-Cor (a network model) has been used to model the void structure of soil by using water retention and mercury porosimetry curves. The model successfully predicts trends in saturated hydraulic conductivity. The effect of the assumptions used in the Pore-Cor geometry have been investigated by comparing of two dimensional slices of the simulated networks with two dimensional image analysis data. The geometric limitations of the model cause packing inefficiencies which prevent the …

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Particle-Water Interactions Of Hydrophobic Organic Micropollutants In Marine Systems, M. Carl Rawling Jan 1998

Particle-Water Interactions Of Hydrophobic Organic Micropollutants In Marine Systems, M. Carl Rawling

School of Geography, Earth and Environmental Sciences Theses

An understanding of the reactivity of hydrophobic organic micropollutants (HOMs) is of paramount importance to water quality managers because of their toxicity, persistence, and liability to bioaccumulate. In this study, the role played by the main estuarine variables (organic matter, suspended particulate matter [SPM], particle type and salinity) on HOM behaviour was investigated by employing samples from estuaries with different geochemical signatures (Chupa, Russia, and the Dart, Plym, Beaulieu and Carnon, U K ) . A laboratory-based technique was developed for the determination of the solubility and sorptive behaviour of HOMs using 14C-labelled, beta-emitting organic compounds (2,2\5,5'-tetrachlorobiphenyl (2,2’5,5'-TCB), bis(2-ethylhexyl)phthalate ester …

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