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An Investigation Of T Cell Dysregulation In B-Cell Chronic Lymphocytic Leukaemia, Sophie Grace Scrivener Jan 2003

An Investigation Of T Cell Dysregulation In B-Cell Chronic Lymphocytic Leukaemia, Sophie Grace Scrivener

Other Faculty of Health Theses

B-cell chronic lymphocytic leukaemia (B-CLL) is characterized by an accumulation of clonal malignant B cells within lymphoid tissue, the bone marrow and the peripheral blood. Whilst abnormalities of these B cells are the essential cause of this disease, the aim of this research project was to investigate whether the T cell compartment may play a role in the aetiology of this disease by evaluating the expression of key surface antigens involved in both activation of and interaction with B cells and other antigen presenting cells of the immune system. There were marked abnormalities in the expression of certain key activation …

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A Study Of The Molecular Genetics Of Renal Cell Carcinoma In Man, Martin Ollerenshaw Jan 2003

A Study Of The Molecular Genetics Of Renal Cell Carcinoma In Man, Martin Ollerenshaw

Other Faculty of Health Theses

The aim was to measure the expression levels of hypoxia inducible factor 1-α (HJF-lα), glucose transporter one (GLUT-1), and vascular endothelial growth factor (VEGF) isoforms 165 and 189 mRNA in patients with renal cell carcinoma (RCC). Patients with RCC underwent radical nephrectomy at Derriford Hospital, Plymouth. Tumour as well as matched normal tissue from the kidney was harvested, snap frozen and stored in liquid nitrogen, and used to quantitate VEGF 165, VEGF 189, GLUT-1 and HJF-1α mRNA expression using ribonuclease protection assays, and quantified using a Phosphor-imager system. The VEGF 165 isoform was increased in the tumour tissue in comparison …

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Profit Efficiency Among Bangladeshi Rice Farmers, S Rahman Jan 2003

Profit Efficiency Among Bangladeshi Rice Farmers, S Rahman

School of Geography, Earth and Environmental Sciences

Production inefficiency is usually analyzed by its three components-technical, allocative, and scale efficiency. In this study, we provide a direct measure of production efficiency of the Bangladeshi rice farmers using a stochastic profit frontier and inefficiency effects model. The data, which are for 1996, include seven conventional inputs and several other background factors affecting production of modern or high yielding varieties (HYVs) of rice spread across 21 villages in three agro-ecological regions of Bangladesh. The results show that there are high levels of inefficiency in modern rice cultivation. The mean level of profit efficiency is 77% suggesting that an estimated …

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Identification Of A Second Proliferating Cell Nuclear Antigen In The Human Malarial Pathogen Plasmodium Falciparum, J-L Li, Av Warren, Ls Cox Dec 2002

Identification Of A Second Proliferating Cell Nuclear Antigen In The Human Malarial Pathogen Plasmodium Falciparum, J-L Li, Av Warren, Ls Cox

School of Biomedical Sciences

Proliferating cell nuclear antigen seems to exist as a single form in higher eukaryotic cells and plays multiple roles in nucleic acid metabolism. We have identified a second additional proliferating cell nuclear antigen (PfPCNA2) in Plasmodium falciparum on the basis of several lines of evidence. (1) PfPCNA2, consisting of 264 amino acid residues with a predicted molecular mass of 30.2kDa, shares only 29% identity and 53% similarity with PfPCNA1 at the amino acid level. (2) Southern blot analyses revealed that the hybridisation pattern of the Pfpcna2 gene is completely different from that of the Pfpcna1 gene. (3) Chromosomal localisation studies …

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Visualisation Of Synchronous Firing In Multi-Dimensional Spike Trains, L Stuart, M Walter, R Borisyuk Oct 2002

Visualisation Of Synchronous Firing In Multi-Dimensional Spike Trains, L Stuart, M Walter, R Borisyuk

School of Engineering, Computing and Mathematics

The gravity transform algorithm is used to study the dependencies in firing of multi-dimensional spike trains. The pros and cons of this algorithm are discussed and the necessity for improved representation of output data is demonstrated. Parallel coordinates are introduced to visualise the results of the gravity transform and principal component analysis (PCA) is used to reduce the quantity of data represented whilst minimising loss of information.

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The Processing Of Holliday Junctions By Blm And Wrn Helicases Is Regulated By P53, Q Yang, R Zhang, Xw Wang, Ea Spillare, Et Al Aug 2002

The Processing Of Holliday Junctions By Blm And Wrn Helicases Is Regulated By P53, Q Yang, R Zhang, Xw Wang, Ea Spillare, Et Al

School of Biomedical Sciences

BLM, WRN, and p53 are involved in the homologous DNA recombination pathway. The DNA structure-specific helicases, BLM and WRN, unwind Holliday junctions (HJ), an activity that could suppress inappropriate homologous recombination during DNA replication. Here, we show that purified, recombinant p53 binds to BLM and WRN helicases and attenuates their ability to unwind synthetic HJ in vitro. The p53 248W mutant reduces abilities of both to bind HJ and inhibit helicase activities, whereas the p53 273H mutant loses these abilities. Moreover, full-length p53 and a C-terminal polypeptide (residues 373-383) inhibit the BLM and WRN helicase activities, but phosphorylation at Ser(376) …

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Saving Europe's Coral Reefs, Jm Hall-Spencer Jun 2002

Saving Europe's Coral Reefs, Jm Hall-Spencer

School of Biological and Marine Sciences

No abstract provided.

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Trawling Damage To Northeast Atlantic Ancient Coral Reefs, Jason Hall-Spencer, Jh Fossa, Valerie Allain Mar 2002

Trawling Damage To Northeast Atlantic Ancient Coral Reefs, Jason Hall-Spencer, Jh Fossa, Valerie Allain

School of Biological and Marine Sciences

10.1098/rspb.2001.1910

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Tnfα Potently Activates Osteoclasts, Through A Direct Action Independent Of And Strongly Synergistic With Rankl., K Fuller, C Murphy, S Fox, B Kirstein, Tj Chambers Mar 2002

Tnfα Potently Activates Osteoclasts, Through A Direct Action Independent Of And Strongly Synergistic With Rankl., K Fuller, C Murphy, S Fox, B Kirstein, Tj Chambers

School of Biomedical Sciences

No abstract provided.

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Internet Delivery Mechanisms For The Continuing Professional Development Of The Marine Engineer, Anne Patricia Mcdermott Jan 2002

Internet Delivery Mechanisms For The Continuing Professional Development Of The Marine Engineer, Anne Patricia Mcdermott

Other Faculty of Science and Engineering Theses

Recent advances in communications technologies enable access to the Internet from anywhere in the world. This has generated interest, demand and research into methods of using and enhancing this technology to deliver Continuing Professional Development (CPD). This research examines issues relevant to the electronic delivery of professional updating to marine engineers in a pro-active manner locating the learner at the centre of the CPD process. Educational theories including experiential learning, andragogy, constructivism and Laurillard's conversational framework are investigated and the importance of learning styles in the design of material based on user needs is examined. A needs analysis of 1117 …

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Copper Toxicity In The Physiology And Early Development Of Fucus Serratus, Hanne Dalsgaard Nielsen Jan 2002

Copper Toxicity In The Physiology And Early Development Of Fucus Serratus, Hanne Dalsgaard Nielsen

School of Biological and Marine Sciences Theses

Fucus serratus was used in a series of laboratory experiments to study the effects of Cu2+ exposure on the early development of zygotes and physiological effects on adults collected from Cu2+ polluted and clean habitats. Comparative studies showed that Cu2+ tolerance in Fucus is an inherited character. Zygote development and growth of embryos and adults during Cu2+ exposure indicated that Fucus serratus from a Cu2+ polluted habitat had a higher tolerance limit than material from two clean habitats. Furthermore, there was no difference in the tolerance level of zygotes, embryos and adults from the same habitat. Chlorophyll fluorescence measurements showed …

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Abiotic Stress Signalling In The Fucus Embryo, Susana Coelho Jan 2002

Abiotic Stress Signalling In The Fucus Embryo, Susana Coelho

School of Biological and Marine Sciences Theses

Fucoid algae live in the intertidal region where they experience daily fluctuations in light and external osmotic environment. High light, especially in combination with ultraviolet (UV) radiation and hyper-osmotic stress affected the cellular physiology of Fucus embryos. Two photoinhibition responses were recognised. Firstly, a rapid decline of the photosystem II (PSII) efficiency, linked with the operation of the xanthophyl cycle, followed by a slower decline correlated with reactive oxygen species (ROS) production. As a result of enhanced ROS production, a slower repair of the PSII efficiency was observed, particularly with increased UV-B doses. Development of the embryos was transiently affected …

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The Molecular Differentiation Of Renibacterium Salmoninarum Isolates, Sarah Margaret Alexander Jan 2002

The Molecular Differentiation Of Renibacterium Salmoninarum Isolates, Sarah Margaret Alexander

School of Biological and Marine Sciences Theses

Studies were undertaken to examine the extent of molecular variation among isolates of the fish pathogen Renibacterium salmoninarum. As many isolates as possible were gathered from diagnostic laboratories within the UK, and checked for viability and contamination. The isolates were derived mainly from infected rainbow trout and Atlantic salmon that were farmed in England, Scotland and Wales, subject to the requirements of statutory legislation. Incomplete histories were available for the sources of the isolates, which spanned a time scale of 36 years, from 1962-1998. Molecular variation between the isolates was examined using two strategies. Firstly, defined regions of the genome …

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Evaluation Of Radionuclide Induced Damage In Marine Invertebrates, Josephine Anne Hagger Jan 2002

Evaluation Of Radionuclide Induced Damage In Marine Invertebrates, Josephine Anne Hagger

School of Biological and Marine Sciences Theses

Limited studies have been carried out to assess the potential effects of ionising radiation on marine organisms. Therefore the general aims of this thesis were, (a) to assess the cytotoxic, genotoxic and developmental effects of ionising radiation on the embryo-larvae of two ecologically relevant marine invertebrates Mytilus edulis and Platynereis dumerilii, (2) to assess the effects of an environmentally relevant cocktail of radionuclides (3) to monitor the potential impact of radiation in the natural environment and finally (4) attempt to predict the potential effects of radiation at a population level. Following validation of developmental stages and mammalian based cytotoxic and …

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Suitability Of Selected Raw Materials And By-Products In Formulated Feeds For Nile Tilapia Oreochromis Niloticus And African Catfish Clarias Gariepinus, Abdel-Wahab A. Abdel-Warith Jan 2002

Suitability Of Selected Raw Materials And By-Products In Formulated Feeds For Nile Tilapia Oreochromis Niloticus And African Catfish Clarias Gariepinus, Abdel-Wahab A. Abdel-Warith

School of Biological and Marine Sciences Theses

The current status of global aquaculture production was reviewed with a special emphasis on Africa and in particular Egypt. The main species of interest in this study were tilapia Oreochromis niloticus and African catfish Clarias gariepinus which are gaining popularity and are of considerable importance in the market of farmed fish in this continent and of economic relevance to Egypt and other Middle Eastern countries. Research was principally directed to establishing the suitability of specific feed ingredients and materials that could be included in balanced diets for both species. Various animal and plant by-products were selected to evaluate their nutritional …

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Chromosomal Variation In Nucella Lapillus (L.) And Other Muricid Gastropods, Philip Lionel Pascoe Jan 2002

Chromosomal Variation In Nucella Lapillus (L.) And Other Muricid Gastropods, Philip Lionel Pascoe

School of Biological and Marine Sciences Theses

The Robertsonian polymorphism (numerical change in the chromosome complement by centric fusion or fission) in the dog-whelk (Nucella lapillus, Mollusca: Gastropoda) has been known and studied sporadically for almost 50 years. However, the possible causes, consequences and proposed correlations of this phenomenon remain enigmatic. Nucella lapillus (2n = 26 to 36), has undergone a marked reduction in chromosome number from its ancestral form; most other muricid species have a diploid chromosome number in the range 2n = 60- 70. Correlations have been proposed between chromosome number (or karyotype) and habitat (wave exposure), and also directly or indirectly with allozymes, shell …

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Toward A Women-Centred Approach To Infant Feeding Research, Lynne Callaghan Jan 2002

Toward A Women-Centred Approach To Infant Feeding Research, Lynne Callaghan

School of Psychology Theses

This thesis aimed to provide an integrated model of infant feeding, centred on women's experiences. Two studies were employed in order to meet this aim. Firstly, a questionnaire-based longitudinal study within a Social Cognitive framework was carried out in order to understand the internal and external processes involved in the infant feeding experience. Eighty-five first time mothers participated in this study. Participants were assessed at three stages; once during pregnancy, once at six to eight, and again at four to six moths postpartum. The results of the longitudinal study supported the use of the Social Cognitive framework, and more specifically …

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Linking Performance Requirements With Process Improvement Actions For Business Process Re-Design, Cita Lorraine Wood Jan 2002

Linking Performance Requirements With Process Improvement Actions For Business Process Re-Design, Cita Lorraine Wood

School of Engineering, Computing and Mathematics Theses

This thesis presents research that extends current knowledge in the area of business process re-design, with a specific focus on the 'Make Product' process within manufacturing organisations. Current business process re-design approaches offer only limited guidance on the specific changes that can be made to a process when re-designing it to achieve the desired performance improvements and often overlook any strategically derived performance requirements when re-designing the process. Case experience suggests that practitioners do not consider the performance requirements of their business processes when re-designing them and that the actions they take to achieve performance improvements are not selected with …

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Intelligent Fault Tolerant Control Schemes For Autonomous Underwater Vehicles, Andrew Raymond Pearson Jan 2002

Intelligent Fault Tolerant Control Schemes For Autonomous Underwater Vehicles, Andrew Raymond Pearson

School of Engineering, Computing and Mathematics Theses

The area of autonomous underwater vehicles (AUVs) is an increasingly important area of research, with AUVs being capable of handling a far wider range of missions than either an inhabited underwater vehicle or a remotely operated vehicle (ROV). One of the major drawbacks of such vehicles is the inability of their control systems to handle faults occurring within the vehicle during a mission. This study aims to develop enhancements to an existing control system in order to increase its fault tolerance to both sensor and actuator faults. Faults occurring within the sensors for both the yaw and roll channels of …

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Precision Control Of A Sensorless Brushless Direct Current Motor System, Matthew John Knight Jan 2002

Precision Control Of A Sensorless Brushless Direct Current Motor System, Matthew John Knight

School of Engineering, Computing and Mathematics Theses

Sensorless control strategies were first suggested well over a decade ago with the aim of reducing the size, weight and unit cost of electrically actuated servo systems. The resulting algorithms have been successfully applied to the induction and synchronous motor families in applications where control of armature speeds above approximately one hundred revolutions per minute is desired. However, sensorless position control remains problematic. This thesis provides an in depth investigation into sensorless motor control strategies for high precision motion control applications. Specifically, methods of achieving control of position and very low speed thresholds are investigated. The developed grey box identification …

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Fluorescence Studies In The Inductively Coupled Plasma, Anita Young Jan 2002

Fluorescence Studies In The Inductively Coupled Plasma, Anita Young

School of Geography, Earth and Environmental Sciences Theses

An Optima 3000 ICP-AES instrument was modified and the equipment necessary to carry out axial excitation atomic fluorescence was designed and constructed. Using this calibrated system, preliminary fluorescence experiments were not successful. As fluorescence is proportional to source intensity, it was considered that the excitation source, a hollow cathode lamp, may not have been sufficiently intense to produce fluorescence. A novel excitation source-driver system was designed and built in-house to operate HCLs, BDHCLs and LEDs with variable modulation frequencies and duty cycle capabilities. Studies investigating lamp response to changes in modulation frequency and duty cycle indicated that a lamp operated …

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Grazing Management And Plant Community Composition On Bodmin Moor, Gavin Stewart Jan 2002

Grazing Management And Plant Community Composition On Bodmin Moor, Gavin Stewart

School of Geography, Earth and Environmental Sciences Theses

The research presented in this thesis was focused on aspects of the dynamic response of upland vegetation to grazing, to allow evaluation of the suitability of Countryside Stewardship (CS) management for the rehabilitation of dwarf-shrub cover in the upland landscape of Bodmin Moor. Initial chapters review the ecological character of Bodmin Moor, grazing management and vegetation in upland habitats, and succession in relation to grazing. Chapter Five provides the first extensive and detailed phytosociological investigation of the vegetation of Bodmin Moor-providing a baseline for further work. It also examines the spatial distribution of the plant communities in relation to environmental …

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Determination Of Additives In Fuels Using Automated Flow Injection Analysis With Chemiluminescence Detection, Philip James Fletcher Jan 2002

Determination Of Additives In Fuels Using Automated Flow Injection Analysis With Chemiluminescence Detection, Philip James Fletcher

School of Geography, Earth and Environmental Sciences Theses

The overall objective of this thesis was to develop field deployable instrumentation for the selective, sensitive determination of additives in diesel fuels using flow injection with chemiluminescence detection. The target analytes were the detergent dodecylamine and the lubricity additive P655. Chapter One describes the types of additives that are used in fully formulated diesel fuels in order to improve performance and outlines the need for robust analytical methods to be able to detect their presence / absences in fuels at the point of distribution, i.e. at the petrol pump. Flow injection (FI), and chemiluminescence (CL) are described as suitable techniques …

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In Situ Monitoring And Biogeochemical Cycling Of Nutrients In Estuarine Waters, Paulo Cesar Ferreira Da Costa Gardolinski Jan 2002

In Situ Monitoring And Biogeochemical Cycling Of Nutrients In Estuarine Waters, Paulo Cesar Ferreira Da Costa Gardolinski

School of Geography, Earth and Environmental Sciences Theses

This thesis describes the use of in situ and laboratory techniques for monitoring nitrate, phosphate and master variables in the environment. Chapter One presents a general overview of nutrients, how they are essential for aquatic biota, their general characteristics and the importance of their behaviour in estuaries. Commonly used analytical methods for nutrient determinations in natural waters are also evaluated. Chapter Two reports the use of chemometrics to determine trends in historical time-series physicochemical datasets {e.g. nitrate+nitrite, phosphate, river flow, precipitation, suspended solids, water temperature and chlorophyll a) from the Tamar catchment, UK. The results provided useful information about correlations …

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Hillslope And Watershed Scale Hydrological Processes And Grazing Management In A Dartmoor Catchment, Southwest England, Erik W. Meyles Jan 2002

Hillslope And Watershed Scale Hydrological Processes And Grazing Management In A Dartmoor Catchment, Southwest England, Erik W. Meyles

School of Geography, Earth and Environmental Sciences Theses

Concerns have been raised on the deterioration of heather moorland due to management in the UK. A study was therefore conducted on the impacts of moorland management on the soils and hydrology of a catchment on Dartmoor. Soil moisture was measured gridwise using TDR on 19 occasions. At 23 sites within this grid, physical properties of the topsoil were obtained. At three locations, tensiometer nests were installed, recording soil suction at 10 cm depth intervals. At the catchment scale, stream discharge and rainfall were recorded. Grazing densities within the watershed were estimated and the observed patterns were related to vegetation …

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The Influence Of Surfactants On The Sorption Of Phenanthrene In Natural Waters, Tracey Louise Jones-Hughes Jan 2002

The Influence Of Surfactants On The Sorption Of Phenanthrene In Natural Waters, Tracey Louise Jones-Hughes

School of Geography, Earth and Environmental Sciences Theses

Polycyclic aromatic hydrocarbons (PAHs) are widely recognised as harmful, persistent organic pollutants, whilst surfactants are more easily degraded but their ubiquitous use both domestically and industrially ensures their presence in natural waters. Owing to both their hydrophobic and hydrophilic properties, surfactants are capable of both adsolubilisation and solubilisation of co-contaminants, hence, their presence in natural waters is considered extremely significant. The purpose of this research was to determine how surfactants and PAHs influence each other in estuaries where both are co-disposed. This study is the first to employ environmentally realistic concentrations of surfactants and to use natural particles in order …

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An Investigation Of Labour Ward Care To Inform The Design Of A Computerised Decision Support System For The Management Of Childbirth, Maureen Harris Jan 2002

An Investigation Of Labour Ward Care To Inform The Design Of A Computerised Decision Support System For The Management Of Childbirth, Maureen Harris

School of Nursing and Midwifery Theses

Patient monitoring is a complex task, particularly during childbirth, where assessment of the baby's condition is inferred from the continuous electronic recording of the baby's heart rate pattern and maternal uterine contractions (CTG). Computerised decision support has long been advocated, as difficulties in the interpretation of the CTG have led to failure to intervene and unnecessary intervention. The problem is large, for obstetric litigation now accounts for 80% of the UK National Health Service litigation bill. The Plymouth Perinatal Research Group has developed a computerised decision support system for patient monitoring during childbirth and the UK Medical Research Council has …

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Unresolved Complex Mixtures Of Aromatic Hydrocarbons In The Marine Environment : Toxicity, Solubility And Photodegradation Studies, Emma Louise Smith Jan 2002

Unresolved Complex Mixtures Of Aromatic Hydrocarbons In The Marine Environment : Toxicity, Solubility And Photodegradation Studies, Emma Louise Smith

School of Geography, Earth and Environmental Sciences Theses

Unresolved complex mixtures (UCMs) of aromatic hydrocarbons have been found in a wide range of environmental matrices at high concentrations. However, limited consideration has been given to the potential detrimental effects of the accumulation of these compounds in the marine environment. In particular, there is a need to evaluate these compounds in the light of recent evidence that points to the long term effects of oil in the marine environment. The overall aim of this work was therefore to investigate unresolved complex mixtures of aromatic hydrocarbons in the marine environment with particular emphasis on assessment of toxicity, aqueous solubility and …

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The Development And Study Of Chelating Substrates For The Separation Of Metal Ions In Complex Sample Matrices, James Cowan Jan 2002

The Development And Study Of Chelating Substrates For The Separation Of Metal Ions In Complex Sample Matrices, James Cowan

School of Geography, Earth and Environmental Sciences Theses

The fabrication and study of high performance chelating substrates for the separation of trace metals using a single column under both isocratic and gradient elutions were investigated. Neutral polystyrene based resins from a variety of manufacturers including a hypercrosslinked resin (MN 200) were functionalised via impregnation with chelating dyestuffs or dynamically modified with small, low molecular weight organic molecules by physical adsorption and chemisorption processes respectively. Improvements in the impregnation of substrates were developed, based upon ultrasonic agitation, along with improvements in the detection of metal ions by the use of a noise reduction system, eluent clean-up procedures and large …

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The Determination Of Copper In Sea Water Using Flow Injection With Chemiluminescence Detection, Richard Charles Sandford Jan 2002

The Determination Of Copper In Sea Water Using Flow Injection With Chemiluminescence Detection, Richard Charles Sandford

School of Geography, Earth and Environmental Sciences Theses

This thesis describes the design, optimisation and shipboard deployment of a flow injection - chemiluminescence (FI-CL) technique for the determination of labile Cu(II) and total copper (by UV irradiation) in seawater. The operational parameters of the FI manifold in a UHP water sample matrix and the 1,10-phenanthroline CL reaction were rigorously optimised. Interferences to the CL reaction were investigated and the good analytical figures of merit obtained presented. The FI-CL method was modified for the determination of ultra trace levels of Cu(II) in seawater by the incorporation of a new design of micro-column containing 8-hydroxyquinoline (8HQ) resin for in-line matrix …

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