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Speciation Of Mercury By Chromatography Coupled With Atomic Spectrometry, Helen Elisabeth Louise Armstrong

School of Geography, Earth and Environmental Sciences Theses

A commercial GC-AFS instrument has been developed and optimised for the speciation of organomercury. This instrument couples a GC oven to a modified atomic fluorescence detector via a ceramic pyrolyser. Organomercury compounds in dichloromethane solvent were directly injected through a Programmable Temperature Vaporiser Injector onto a DBl Megabore column. Once separated, the compounds eluted from the column and were atomised in the pyrolyser then detected by AFS. The direct injection technique, ceramic pyrolysis design and argon purged detector have improved previous instrument designs by enhancing and maintaining sensitivity. The instrumental limit of detection was determined to be 0.25 pg Hg …

The Fabrication And Study Of Metal Chelating Stationary Phases For The High Performance Separation Of Metal Ions, Matthew James Shaw

School of Geography, Earth and Environmental Sciences Theses

The preparation and characterisation of chelating sorbents suitable for the high efficiency separation of trace metals in complex samples, using a single column and isocratic elution, is described. Hydrophobic, neutral polystyrene divinylbenzene resins were either impregnated with chelating dyes or dynamically modified with heterocyclic organic acids, using physical adsorption and chemisorption processes respectively. A hydrophilic silica substrate was covalently bonded with a chelating aminomethylphosphonic acid group, to assess the chelating potential of this molecule. These substrates were characterised in terms of metal retention capability (selectivity coefficients and capacity factors), separation performance, column efficiency and suitability for analytical applications. Chelating molecules …

Complexation And Particle-Water Interactions Of Nickel In Estuaries, Manuela Martino

School of Geography, Earth and Environmental Sciences Theses

The speciation and particle-water interactions of Ni were investigated in three estuaries with contrasting pollution levels, hydrodynamics and geochemical characteristics. Samples of water and sediments were collected seasonally from the Tamar, Tweed and Mersey Estuaries. The chemical speciation of dissolved Ni was determined by adsorptive cathodic stripping voltammetry (ACSV), and the sorptive behaviour of Ni was studied under simulated estuarine conditions using " Ni coupled to liquid scintillation counting. A relatively high particle reactivity was observed only in the Tamar Estuary, where ACSV-non labile Ni was removed in the low salinity region, followed by addition of ACSV-labile Ni in the …

Fundamental Studies Of Interferences In Icp - Ms, Linda Kathleen Rowley

School of Geography, Earth and Environmental Sciences Theses

Methods of temperature measurement by mass spectrometry have been critically reviewed. It was concluded that the most appropriate method depended critically on the availability of fundamental data, hence a database of fundamental spectroscopic constants, for diatomic ions which cause interferences in ICP-MS, was compiled. The equilibration temperature, calculated using the different methods and using various diatomic ions as the thermometric probes, was between c.a. 400 - 10,000 K in the central channel, and between c.a. 600 - 16,000 K when the plasma was moved 1.8 mm off-centre. The wide range in temperature reflected the range of temperature measurement methods and …

The Determination Of Trace Metals By Capillary Electrophoresis, Simon Andrew Hardy

School of Geography, Earth and Environmental Sciences Theses

The development of a capillary electrophoresis (CE) method for the determination of inorganic and organo mercury species as their dithizone sulphonate (DzS) complexes using coated capillary columns is described. The complexes were pre-formed before injection and detection was by direct measurement of the visible absorbance of the complexes. Dithizone sulphonate was used in place of cysteine to separate methyl mercury in the final stage of a simplified Westoo extraction procedure. The method was than applied to the analysis of methyl mercury in a crab and several fish meat samples. Good quantitative performance is demonstrated by spiking experiments and analysis of …

Measurement And Modelling Of Estuarine Chemistry, Adrian Gavin Punt

School of Geography, Earth and Environmental Sciences Theses

A l-D tidally resolving hydrodynamic model of the Tweed Estuary has been encoded using the Estuarine Contaminant Simulator, ECoS. The model results of axial and time series variations in water elevation, salinity and turbidity are compared to field data recorded during the LOIS survey programme. The organic and inorganic controls on estuarine pH have also been investigated by encoding a new template to predict the effect of changing salinity and temperature on the pH of estuarine water. The template has been coupled to the hydrodynamic model to predict pH variations in the estuary. The model results have shown conservative behaviour …

The Effects Of Hydrology And Nutrient Inputs At South Milton Ley On The Ecology Of The Common Reed Phragmites Australis (Cav. Trin. Ex Steudal), Paula Angele Powell

School of Geography, Earth and Environmental Sciences Theses

South Milton Ley is a small coastal wetland in Southern England. A sand-bar forms periodically at its seaward end and separates fresh water from the sea. The common reed Phragmites australis dominates the wetland and when a sand bar is present a shallow freshwater lake forms. Monthly water budgets were prepared for the years 1994, 1995 and 1996 and intermittent flooding of the Ley was also monitored. This information was used to calculate a range of residence times (between one hour and eleven days) and the characteristics of various flow regimes when the sandbar, which dams the Ley, is open …

The Quantitative Isolation Of 'Insoluble Organic Matter' (Iom) From Sediments And Bacteria, And Its Attempted Dissolution Using The Ionic Liquid L-Ethyl-3- Methylimidazolium Chloride-Aluminium (Hi) Chloride, Paul Sutton

School of Geography, Earth and Environmental Sciences Theses

Organic matter which is insoluble in common solvents and non-oxidising acids often comprises the quantitatively most important fraction of organic matter in sediments. This operationally defined material is usually simply termed 'insoluble organic matter' (IOM) or 'kerogen' when it is isolated from ancient sediments. Indeed, kerogen is regarded as the most abundant form of carbon on the planet. The molecular character of this generic material has not been fully elucidated, principally because of its insolubility which limits instrumental methods of analysis to those applicable to solid substrates. This thesis describes the quantitative isolation of IOM from lacustrine and marine sediments …

Export Production And Carbonate Dissolution In The Central Equatorial Pacific Ocean Over The Past 1 Myr, R. W. Murray, Christopher W. Knowlton, M. Leinen, A. C. Mix, C. H. Polsky

Graduate School of Oceanography Faculty Publications

In order to quantify changes in export production and carbonate dissolution over the past 1 Myr in the central equatorial Pacific Ocean we analyzed Ba, P, Al Ti, and Ca in 1106 samples from five piston cores gathered from 5°S to 4°N at 140°W. We focused on Ba/Ti, Al/Ti, and P/Ti ratios as export proxies and employed areally integrated time slice as well as time series strategies. Carbonate maxima from 0–560 kyr are characterized by 15–30% greater export than carbonate minima. The increases in export fall on glacial δ¹⁸O transitions rather than glacial maxima. From 560–800 kyr, overlapping …

When Daddy Wants Out: The Issue Of Paternity, Jane C. Murphy, Cheri Wyron Levin

All Faculty Scholarship

Perhaps you've seen the signs along a number of major highways in Maryland. A pregnant Mona Lisa advertising a DNA testing company with the caption "Who's the Daddy?" With the rise in the number of children born out of wedlock in Maryland in the last several decades, paternity testing is becoming routine and family law practitioners are handling more cases in which the father or mother or both are trying to change who is named as the legal father in a paternity or divorce judgment. The law governing such cases has changed substantially since 1995. This article will guide the …

A Study Of The Molecular Immunogenetics Of Type 1 Diabetes In Man, Mohamed Mirza Jahromi

Other Faculty of Health Theses

Type 1 diabetes is caused by immune destruction of pancreatic β cells. There is increasing evidence that genes outside the MHC region contribute to the pathogenesis of type 1 diabetes. Cytokines due to their role in immune regulation seem to play a crucial role in the pathogenesis of the disease. Three hundred and eight patients with type 1 diabetes and 150 normal controls were genotyped for polymorphism in the genes for IFN-γ, IL-4, IL-6, and TGF-β1. All assays employed in this study were PCR based. The IFN-γ CA repeats was an octa-allelic repeat and the 3 / 3 genotype showed …

Emission, Dispersion And Local Deposition Of Ammonia Volatilised From Farm Buildings And Following The Application Of Cattle Slurry To Grassland, Richard Alexander Hill

Other Faculty of Science and Engineering Theses

Emissions of ammonia (NH3) into the atmosphere, principally from agricultural sources, have been implicated in the pollution of forests, moorlands and grasslands, through the subsequent deposition of reduced nitrogen (NHx -N). Consequently, legislation has been implemented to control both the transboundary transport and local environmental impacts of NHx. This thesis investigates the emission, dispersion and local deposition of NH3 from two sources that are major components of national NH3 emissions inventories, slurry applied to grassland and naturally ventilated cattle buildings. A N balance method was identified for determining the time-average deposition of NH3 downwind of a farm building, whilst an …

The Mechanism Of Action Of Liquid Seaweed Extracts In The Manipulation Of Frost Resistance In Winter Barley (Hordeum Vulgare. L), Stephen Burchett

Other Faculty of Science and Engineering Theses

Frost assays carried out on winter barley (Hordeum vulgare cv Igri) showed that a single (10ml I) application of liquid seaweed extract (LSE) marginally increased the frost resistance of non-acclimated (NA) plants by 2.3% compared to NA controls and cold-acclimated (CA) plants by 2.1% compared to CA controls. Three applications of LSE increased the frost resistance of NA plants by 16% compared to NA controls and CA plants by 7.5% compared to CA controls. These observations were durable in a small scale field trial where LSE increased plant dry weights (control 0.55, single LSE, 0.611 and multiple LSE 0.621 log …

The Effects Of Low Ph On Sunfish Assemblages In Southeast Georgia, William Boyd Tate

College of Graduate Studies: Theses & Dissertations (1964–2006)

No abstract provided.

Effects Of Height And Vegetation On Success Of Bird Nests In Maritime Forests, Sharon M. Defalco

College of Graduate Studies: Theses & Dissertations (1964–2006)

Nest predation is an important source of mortality in songbirds and may contribute to declines in Neotropical migrants. I used artificial nests baited with fresh Japanese Quail and Zebra Finch eggs in conjunction with observations of natural nests to quantity the ettects ol nest height and vegetation on nest predation on St. Catherine's Island, a barrier island in southeast Georgia. Because of intense browsing by white-tailed deer. I predicted that lower, more exposed nests would be least successful. Artificial nests (n = 389) were placed in the field, and natural nests (n = 49) were observed, durintz April and May …

A Descriptive Study Of Public Alternative Schools In Georgia, Willie James Wiley

College of Graduate Studies: Theses & Dissertations (1964–2006)

The purpose of this study was to identify the types of alternative schools in Georgia, to describe the characteristics of the alternative schools, and their students, and to determine the primary goals of the alternative schools. The descriptive information was collected from 97 public alternative schools. The data collected by a 44 item multiple response survey included the perceptions of Georgia's alternative school administrators. The survey items were developed from a literature search and site visits to five different models of alternative schools in a large urban school system The responses were categorized to calculate the range, mean, percentages, and …

Barriers To Female Principals: Perceptions Of Female High School Administrators In Georgia, Jane Spires Hilliard

College of Graduate Studies: Theses & Dissertations (1964–2006)

The purpose of this study was to determine what factors female high school principals and assistant principals in Georgia perceived as barriers to women entering high school principalships. The factors presented to the participants were determined by a thorough review of the literature. A survey instrument with two sections was developed. Section one consisted of 12 factors often mentioned as barriers to women entering high school principalships. These factors were rated on a Likert scale which ranged from strongly agree to strongly disagree. Participants were also given the opportunity to list any other factors they perceived as barriers. The second …

Cloning And Sequencing Of Sodium-Hydrogen Exchanger In The Gills Of The Long-Horned Sculpin (Myoxocephalus Octodecimspinosus), Danielle Lee Gunning

College of Graduate Studies: Theses & Dissertations (1964–2006)

No abstract provided.

South Asian Divorce And Disputes Involving Children Of South Asian Origin, William Hay

Other Faculty of Arts, Humanities and Business Theses

This thesis is concerned with two discrete but related themes that are of considerable socio-legal significance: South Asian divorce and disputes involving South Asian children. Both themes are explored empirically by means of a qualitative research study conducted in an urban and industrial area of Britain with a high South Asian population. The thesis thus seeks to provide much needed information concerning what are currently two poorly understood social problems. The material is presented in three main sections. The first section provides the wider context to the study including a discussion of the changing face of South Asian social relations …

Processing Writing: From Text To Textual Interventions, Caroline Bergvall

Other Faculty of Arts, Humanities and Business Theses

This submission comprises the main bulk of the critical and textual work I have researched and developed over the last five years. Throughout this period, I have been particularly interested in exploring issues of interdisciplinarity for writers and text-practitioners, at both a critical and a methodological level. An interest in cross-media and site-related approaches to writing plays an important role in this. This is reflected in the thematics of the various critical texts, as well as in the fairly broad range of textual modes submitted. As a whole, this work can be seen in close continuity with my pedagogical involvement …

The Relationship Between Teachers' Understanding Of The Nature Of Science And Their Science Practice : Four Case Studies From An Urban Primary School., Stephen Laurence Waters-Adams

Plymouth Institute of Education Theses

This thesis explores the relationship between a teacher's understanding of the nature of science and her practice. The idea that teachers' understanding of the nature of science is a powerful determinant of their actions in the classroom has a strong intuitive appeal. Research over the last forty years has provided inconclusive results; however, there is a clear implication within recent central policy on teacher education that such knowledge should translated directly into practice. This has led to the identification within teacher training, materials of specific expectations regarding understanding of the nature of science (DfEE 1998a). This thesis presents four case …

The Effectiveness Of An Education Intervention Related To Knowledge Increase Among Adolescents Regarding Dietary Calcium And Prevention Of Osteoporosis, Deborah K. Fast

Masters Theses

The purpose of this study was to assess the effectiveness of an educational intervention for 6th - 11th grade adolescents regarding dietary calcium and the prevention of osteoporosis. This was a secondary analysis of data from a study that used a pre-experimental pre-test-post-test; no control group design. Eighty-two boys and 102 girls completed the Healthy Bones Knowledge Questionnaire (HBKQ) as a pretest, received an educational intervention based primarily on dietary calcium intake, then completed the questionnaire again as a post-test.

As a group, the students demonstrated a significant increase in correct answers to calcium-related HBKQ items (t = 3.31, p …

Multi-Sensor 3d Image Fusion And Interactive Search, W. D. Ross, A. M. Waxman, W. W. Streilein, M. Aguilar, J. Verly, F. Liu, M. I. Braun, P. Harmon, S. Rak

Research, Publications & Creative Work

We describe a system under development for the 3D fusion of multi-sensor surface surveillance imagery, including electro-optical (EO), IR, SAR, multispectral and hyperspectral sources. Our approach is founded on biologically-inspired image processing algorithms. We have developed an image processing architecture enabling the unified interactive visualization of fused multi-sensor site data which utilizes a color image fusion algorithm based on retinal and cortical processing of color. We have also developed interactive Web-based tools for training neural network search agents that are capable of automatically scanning site data for the fused multi-sensor signatures of targets and/or surface features of interest. Each search …

The Systemic Redesign Of Manufacturing Systems In Small To Medium Sized Enterprises, John William George Bradford

School of Engineering, Computing and Mathematics Theses

The research problem was to develop a new approach for redesigning manufacturing systems within Small to Medium sized Enterprises (SMEs). Field observation together with literature review showed that methodologies propounded in theory were not being applied in practice. The research presents a new methodology for the systemic redesign of manufacturing systems within SMEs. The methodology consists of a four phase iterative design strategy consisting of Planning, Risk Assessment, Action and Evaluation leading to the next Planning phase. This is given a systemic basis through four perspectives: Structure; People; Process; and Technology; which frame and guide the Planning phase. Prior to …

Evolutionary Decomposition Of Complex Design Spaces, Christopher Richard Bonham

School of Engineering, Computing and Mathematics Theses

This dissertation investigates the support of conceptual engineering design through the decomposition of multi-dimensional search spaces into regions of high performance. Such decomposition helps the designer identify optimal design directions by the elimination of infeasible or undesirable regions within the search space. Moreover, high levels of interaction between the designer and the model increases overall domain knowledge and significantly reduces uncertainty relating to the design task at hand. The aim of the research is to develop the archetypal Cluster Oriented Genetic Algorithm (COGA) which achieves search space decomposition by using variable mutation (vmCOGA) to promote diverse search and an Adaptive …

Exploring And Exploiting Models Of The Fitness Landscape: A Case Against Evolutionary Optimization, Jonathan Paul Moore

School of Engineering, Computing and Mathematics Theses

In recent years, the theories of natural selection and biological evolution have proved popular metaphors for understanding and solving optimization problems in engineering design. This thesis identifies some fundamental problems associated with this use of such metaphors. Key objections are the failure of evolutionary optimization techniques to represent explicitly the goal of the optimization process, and poor use of knowledge developed during the process. It is also suggested that convergent behaviour of an optimization algorithm is an undesirable quality if the algorithm is to be applied to multimodal problems. An alternative approach to optimization is suggested, based on the explicit …

A Mathematical Model For Spatially Varying Extracellular Matrix, J. C. Dallon, J. A. Sherratt

Faculty Publications

Orientation of extracellular matrix fibers in the skin is a key ingredient of tissue appearance and function, and differences in fiber alignment are one of the main distinctions between scar tissue and normal skin. In this paper, the authors develop a mathematical model for alignment of collagen fibers and the fibroblast cells that remodel them; the model extends previous work in which spatial variation was excluded. Numerical simulations of the model are presented, which show spatial variations in alignment over long transients, but with spatially uniform behavior in the long term. This is investigated further via asymptotic analysis, using the …

Scallop Dredging Has Profound, Long-Term Impacts On Maerl Habitats, J. M. Hall-Spencer, P. G. Moore

School of Biological and Marine Sciences

No abstract provided.

Limaria Hians (Mollusca: Limacea): A Neglected Reef-Forming Keystone Species, J. M. Hall-Spencer, P. G. Moore

School of Biological and Marine Sciences

1. The case is made for recognition of the marine bivalve Limaria hians as a reef-forming species, which plays a key architectural role in certain benthic communities around the United Kingdom and Ireland. 2. This species uses byssal threads to construct nests that can coalesce to form reefs that cover hectares of seabed, contain multiple conspecifies and bind sediment. In so doing, L. hians modifies physical, chemical and biological processes at the sediment-water interface. 3. Such nests support a high diversity of associated organisms in coarse-grade sediments (19 species of algae and 265 species of invertebrates from six discrete nests …

Transport Of Fine Sediment With Mesoscale Currents In The Shelf-Slope Zone Of The Sea, Gi Shapiro, Tm Akivis, Nv Pykhov, Sm Antsyferov

School of Biological and Marine Sciences

No abstract provided.