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Structure - Activity Relationships In Some Herbicidal Fluorene Derivatives, Michael William Hartnell Jan 1979

Structure - Activity Relationships In Some Herbicidal Fluorene Derivatives, Michael William Hartnell

School of Geography, Earth and Environmental Sciences Theses

Synthetic plant-growth regulators derived from fluorene-9-carboxylic acid ('morphactins') are introduced and the literature on them is reviewed. Similar herbicidal activity has been found with 9,9-bishydroxymethylfluorene, a compound which can be obtained directly from the hydrocarbon fluorene. There follows a detailed review of the chemistry of fluorene and 9,9- bishydroxymethylfluorene. 9-Substituted and ring-substituted derivatives of this diol have been synthesised and their chemistry and biological activity are discussed. The hydroxymethylation of substituted fluorenes is possible on a small scale in suitable solvents which do not stabilise the corresponding radical anions. This radical anion formation, when it occurs, seriously reduces the yield …

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Pedagogic Styles In Physics Teaching: An Attitude Scaling And Repertory Grid Study, Terence R. Keen Jan 1979

Pedagogic Styles In Physics Teaching: An Attitude Scaling And Repertory Grid Study, Terence R. Keen

Other Faculty of Arts, Humanities and Business Theses

The need for a greater understanding of the teaching-learning process in higher education is clearly evident from the rapid increase in research activity in this area over the last decade. Economic and political pressure often defines the rationale for such research in terms of increased efficiency; it is the author's contention that such an outcome might still result even if the emphasis is shifted towards effectiveness. Indeed it is the body of academics who are concerned with staff development that have redefined the problem in these terms. Much research has concentrated on the outcomes of the teaching-learning process in order …

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The Structural And Physical Properties Of Crystalline Antibiotic Materials, Patrick Arthur Charles Gane Jan 1979

The Structural And Physical Properties Of Crystalline Antibiotic Materials, Patrick Arthur Charles Gane

School of Engineering, Computing and Mathematics Theses

Effectiveness in biological chemical environments virtually defines the term 'drug' when applied to any attempt to modify that environment by the introduction of an influence in terms of a specific compound or group of compounds. Interest in the configuration of the molecules involved in such modifications led to the X-ray structure determinations, discussed in the thesis, of the following three compounds: (i) 7-chloro-2-methyl-5-phenyl-3-propyl [2,3-b]-imidazolyl quinoline. Derived from the psychoactive drug Librium, it was thought to conform to the structure, containing the highly strained 4-membered monocyclic azete system (Shenoy, a thesis submitted for the degree of Doctor of Philosophy, University of …

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The Real Performance Of Some Civil Engineering Structures, Clive Williams Jan 1979

The Real Performance Of Some Civil Engineering Structures, Clive Williams

School of Engineering, Computing and Mathematics Theses

The work carried out during this research project has been concerned with the performance of large structures and in the introduction to this thesis a justification for full-scale testing is presented. Full-scale testing techniques relating to both dynamic and quasi-static movements occurring in large civil engineering structures such as multi-storey buildings and bridges have been studied. Dynamic characteristics of buildings were obtained during full-scale testing with the use of seismometers and servo-drive accelerometers. Oscillations produced from both by wind and by forced vibration have been studied and the methods and results obtained are compared. The slow movement of structures, occurring …

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Investigation Of Parameters Affecting The Operating Characteristics Of Toggle-Switches With Silver-Cadmium-Oxide Contacts, Peter J. White Jan 1979

Investigation Of Parameters Affecting The Operating Characteristics Of Toggle-Switches With Silver-Cadmium-Oxide Contacts, Peter J. White

School of Engineering, Computing and Mathematics Theses

Experimental and theoretical studies are made of small snap-action switches designed for use in thermostatic controls operating on a.c. at 240 volts r.m.s., 50Hz. The performance of the silver cadmium oxide contacts (Ag. CdO, 85/15%) is evaluated over a range of currents from 1 to 10 amps, for make and break operations. The arc at break is found to be the predominant factor contributing to the erosion of the contacts for the range of currents used. Tests using a high speed camera show that the energy dissipated in the arc between the contacts can be evaluated from equations describing the …

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Operation Of V.L.C.C.'S In Heavy Weather, Staffan Robertsson Jan 1979

Operation Of V.L.C.C.'S In Heavy Weather, Staffan Robertsson

School of Engineering, Computing and Mathematics Theses

A short review is presented of available instrumentation systems designed to assist the operation of ships in heavy weather by warning against dangerous wave loads. Some systems also give guidance to the master by predicting the outcome of evasive actions, and the bases on which such predictions are made, such as visual observations of the wave system, are questioned. A method is presented in which the motions of the ship are used to determine the sea state in the form of an "equivalent" wave spectrum. Two investigations of the possibility of improving the guidance capability of warning instruments are described, …

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The Immune Response Of The Dogfish Scyliorhinus Canicula L., W.J.W. Morrow Jan 1978

The Immune Response Of The Dogfish Scyliorhinus Canicula L., W.J.W. Morrow

School of Biological and Marine Sciences Theses

A number of aspects of the humoral and cellular immune responses of the common dogfish Scyliorhinus canicula L. were examined in order to define the immunological status of the animal in relation to its phylogenetic origins. The dogfish was shown to have the ability to produce specific antibody in response to a variety of soluble and particulate protein antigens. The existence of several non-specific defence mechanisms was demonstrated including a well established reticulo-endothelial system capable of rapidly clearing injected foreign material from the blood and also the bacteriolytic enzyme, lysozyme. Specific antibody from the fish had marked agglutinating properties which …

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Cenomanian Ostracoda From Southern England: Their Taxonomy, Stratigraphy And Palaeoecology, Philip P.E. Weaver Jan 1978

Cenomanian Ostracoda From Southern England: Their Taxonomy, Stratigraphy And Palaeoecology, Philip P.E. Weaver

School of Biological and Marine Sciences Theses

Eight sections of Cenomanian Chalk from Southern England have been examined for their Ostracoda. A total of 111 species and 3 sub-species have been found and these fall into 47 genera. 38 of these species have been previously described, 47 are new and the r e s t have been left under open nomenclature. A generalised distribution chart for some of the more important species has been drawn up and the distribution of species in each individual section has been compared to this chart. As a result it can be seen that Ostracoda can be very useful in stratigraphic work …

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An Investigation Of The Effects Of Father Absence On Children Aged Between Five And Eleven Years, Monica Hayes Jan 1978

An Investigation Of The Effects Of Father Absence On Children Aged Between Five And Eleven Years, Monica Hayes

School of Psychology Theses

The effects of permanent and intermittent father absence on the cognitive development and the emotional and behavioural problems of children aged between 5 and 11 years were examined. There were two investigations. In the first of these 53 children aged between 5 and 7 years were studied. In the second investigation there were two samples, one of 52 children aged between 5 and 7 years and the other of 54 children aged between 8 and 11 years. The samples were drawn randomly from the population of a city. Middle class and working class male and female children were included. All …

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Property-Microstructural Relationships In Gfrp, Felicity Jean Guild Jan 1978

Property-Microstructural Relationships In Gfrp, Felicity Jean Guild

School of Engineering, Computing and Mathematics Theses

This work consists of an investigation into the microstructure and mechanical behaviour of glass fibre reinforced polyester resin beams. The volume fraction occupied by glass fibres was 20-30%, which is that typically used in boat building. The beams tested were all unidirectional, with fibres oriented parallel or perpendicular to the long axis of the beam. Various techniques have been developed which may be applicable to other composite materials. The microstructure of the beams was investigated by observation of cross-sections using a Quantimet 720 Image Analysing Computer. Volume fractions and the distribution. of fibre cross-sectional areas were measured. Methods have been …

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Reactivity Of Lime And Related Materials With Sulphur Dioxide, Peter O'Neill Jan 1978

Reactivity Of Lime And Related Materials With Sulphur Dioxide, Peter O'Neill

School of Geography, Earth and Environmental Sciences Theses

A study has been made of reactions between some alkaline earth metal compounds and sulphur dioxide. The compounds studied included naturally-occurring forms, limestone and dolomite, and industrial products, Limbux and quick-lime. Particular attention was paid to reactions which could have proved useful in the desulphurisation of industrial flue gases. All the substances used reacted to some extent with sulphur dioxide, but often slowly. The greatest reactivity was shown by calcium-based compounds as the carbonate or hydroxide decomposed to form fresh, highly active calcium oxide. Reaction rates, below 400°C, were only appreciable for calcium oxide. The reaction products, depending upon conditions, …

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A Foraminiferal Biostratigraphy Of The Lower Senonian, Haydon William Bailey Jan 1978

A Foraminiferal Biostratigraphy Of The Lower Senonian, Haydon William Bailey

School of Geography, Earth and Environmental Sciences Theses

The necessity for a micropalaeontological examination of the lower Senonian chalk of southern England was established during the site investigation of the Thames Barrier, which Is founded on chalk of the Micraster zones. There has been a large amount of detailed stratigraphic and micropalaeontological research carried out on the Late Cretaceous deposits of Europe, and this provides a historical framework onto which the present research is placed. Samples from three of the Thames Barrier boreholes were studied initially to provide an Indication of the microfauna and it's stratigraphic setting. This was followed by the collection and examination of a further …

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Studies On The Distribution And Physiology Of Lead In Plants, Stuart David Lane Jan 1978

Studies On The Distribution And Physiology Of Lead In Plants, Stuart David Lane

School of Geography, Earth and Environmental Sciences Theses

The studies reported herein cover two main areas of research. The distribution of lead through the plant has been monitored using histochemical and quantitative techniques, and physiological responses of the plant to lead contamination have been examined. In seeds the testa prevents lead contamination of the embryo prior to germination. In seedlings root-applied lead is capable of essentially unrestricted movement through the plant, although anomalies in distribution exist. The metal is sequestered during its passage through the plant, and the endodermis offers a partial barrier to lead movement, restricting contamination of the aerial parts of the plant. In cotyledon leaves …

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Dimensional Responding In Children And Adults As A Function Of Stimulus And Response Variables, Thomas Bernard Ward Jan 1978

Dimensional Responding In Children And Adults As A Function Of Stimulus And Response Variables, Thomas Bernard Ward

Other Faculty of Health Theses

Restricted classification and similarity rating tasks employing the dimensions of line length and density were used to investigate several issues. One of these was developmental differences in the overall separability of those dimensions. The contribution of perceptual limitation and strategic factors to levels of dimensional responding and to developmental changes in that responding were also investigated. Finally, changes in levels of dimensional responding across trials with stimuli and the contribution of those changes to observed developmental differences were studied.

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The Infestation Of Molluscs By Polydora Spp., Richard Michael Leslie Kent Jan 1977

The Infestation Of Molluscs By Polydora Spp., Richard Michael Leslie Kent

School of Biological and Marine Sciences Theses

The ecology of Polydora, epp was reviewed and the infestation of molluscs by the boring, spionid polychaete, Polydora ciliata, was studied in detail. X-radiography showed that, P. ciailt a infested a wide variety of molluscan substrates, but it . occurred in greatest abundance on large, rough-surfaced, epibenthic shells, which were collected from the-sublittoral zone and the level of extreme low water spring tides, of shores sheltered from wave action. P. ciliata was contagiously dispersed on mussel--shells. Monthly radiographs of mussels indicated that maximum settlement of P. ciliata larvae in the river Fowey, 1 occurred in May. The effect of heavy …

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The Host-Parasite Interface, Jacqueline C. Higgins Jan 1977

The Host-Parasite Interface, Jacqueline C. Higgins

School of Biological and Marine Sciences Theses

Metacercarial cysts of Bucephalus haimeanus naturally infect Pomatoschistus microps collected from the Tamar Estuary, Devon. Cysts occur throughout the liver, greater concentrations being found around the gall bladder, blood vessels and periphery of the liver. The cyst wall is composed of three layers, an inner granular, middle vacuolated and outer nucleated layer. The inner layer consists of three zones, an inner zone of irregularly-compacted, granular material, a middle densely-compacted zone and an outer moderately-compacted zone. Only small amounts of collagen and very few leucocytes are associated with the cysts.

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Study Of Taylor Instabilities And Turbulence In Lubricating Films, Michael Geoffrey Short Jan 1977

Study Of Taylor Instabilities And Turbulence In Lubricating Films, Michael Geoffrey Short

School of Engineering, Computing and Mathematics Theses

The development of the wavy mode of Taylor vortices in the flow between a rotating inner cylinder and a stationary outer cylinder has been investigated by visual observations using a stroboscopic technique and by inner cylinder torque measurements. Radius ratios of 0.874, 0.911, 0.950 and 0.975 have been tested for the concentric and eccentric cylinder cases. The stability of wavy mode flow has been found to decrease with increasing radius ratio and/or increasing eccentricity. Observations of the flow suggested that the wavy mode can be classified into three regimes called, respectively, the primary, transitional and secondary modes. The three regimes …

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An Experimental Study Of Iron And Vanadium Associated With Kaolinite, Wendy E.J. Vincent Jan 1977

An Experimental Study Of Iron And Vanadium Associated With Kaolinite, Wendy E.J. Vincent

School of Engineering, Computing and Mathematics Theses

This thesis is divided into six chapters. In the first chapter relevant previous studies of kaolinite are summarised and in particular a review of past electron spin resonance studies of kaolinite is included. The experimental results are presented in four chapters. Chapter 2 describes an investigation of the vanadium impurities associated with natural kaolinites from Georgia, U.S.A. By following the changes in the electron spin resonance spectra of these samples with magnetic separation, thermal and chemical treatments, preferential orientation and relative humidity, it is shown that vanadium is substituted in the kaolinite structure, probably in the octahedral layer, as V4+ …

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Rheological Characterization Of Suspensions, Susan Anne Bullivant Jan 1977

Rheological Characterization Of Suspensions, Susan Anne Bullivant

School of Engineering, Computing and Mathematics Theses

The aim of this research is to obtain a meaningful rheological characterization of deflocculated china clay suspensions. It is generally true that in the study of suspensions relatively little successful work has been carried out on the flow properties of highly concentrated suspensions as compared with dilute suspensions; it was decided therefore that the work, presented in this thesis, should be confined to the study of higher concentration suspensions. A survey is given of previous work on the rheological characterization of suspensions and the reasons for choosing the clay suspensions in particular, are discussed. Since a knowledge of the microscopic …

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A Structural And Functional Study Of Stomata, R.A. Stevens Jan 1977

A Structural And Functional Study Of Stomata, R.A. Stevens

School of Geography, Earth and Environmental Sciences Theses

Substomatal ion-adsorbent bodies are reported on here for the first time. A brief survey of the plant kingdom suggests that the structures are mainly restricted to the Commelinaceae and Filicales although analogous structures way occur in other plant groups. Microscopical studies indicate that the bodies have a solid external aspect, a hollow lumen, and are situated extracellularly. In Polypodium, the bodies are narrowly attached to the lower periclinal walls in the polar regions of the guard cell complex, whilst in Tradescantia they are located in the intercellular space between the poles of the complex and the adjacent subsidiary cells. In …

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An Investigation Into The Synthesis Of The Dipyrrolo Pyrrolo And Imidazopyrrolopyridine Systems, Frederick Arthur Charles Cooke Jan 1977

An Investigation Into The Synthesis Of The Dipyrrolo Pyrrolo And Imidazopyrrolopyridine Systems, Frederick Arthur Charles Cooke

School of Geography, Earth and Environmental Sciences Theses

Previous work on the production of dipyrrolo and imidazopyrrolo - pyridine systems has been reviewed. Methods for the preparation of 2,4-diaminopyridines have been reviewed and attempted. The resulting diamines have been subjected t o t he Bischler reaction to produce a new dipyrrolopyridine system and new derivative s of known systems. The application of the Bischler reaction to all the possible diaminopyridines has been attempted. This produced a number of new derivative s and ring systems. Some information of the factor s influencing the effectiveness of the Bischler reaction on the pyridine system have been obtained.

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Sequential Experiences In Architecture: Computer Simulation Of Human Response To The Physical Environment, G Mckennan Jan 1977

Sequential Experiences In Architecture: Computer Simulation Of Human Response To The Physical Environment, G Mckennan

School of Art, Design and Architecture Theses

The importance of the sequential experience of architecture has long been recognised by architects. Section 1 outlines some of the ways this has been done in the past and sets the present work in its architectural context. Section 2 discusses the environmental factors and the dynamic thermal regulatory mechanisms involved in predicting people’s responses to changes in the thermal environment. Section 3 describes previous attempts at simulating the regulatory mechanisms involved, using control system equations. Fanger's model is discussed in this section to illustrate the limitations of models that ignore the body's regulatory actions. Section 4 is new work and …

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The Impact Of A Liquid Drop With A Solid Surface And The Effects Of The Properties Of The Liquid On The Erosion Of Solids, Michael Colin Rochester Jan 1977

The Impact Of A Liquid Drop With A Solid Surface And The Effects Of The Properties Of The Liquid On The Erosion Of Solids, Michael Colin Rochester

Other Faculty of Science and Engineering Theses

Why are sea-walls damaged by breaking waves? What is the load on the bottom of a ship when it slams down onto the surface of the sea? How are the leading edges of steam turbine blades damaged by water droplets? Is it safe to fly an aircraft through a rainstorm? These questions have one thing in common - they concern impact between a liquid and a solid. In the last fifty years or so they have inspired a large number of investigations.

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Redefinition Of A Syntactic Category In Modern Spanish As A Method Of Facilitating A Computer-Assisted Textual Analysis, Colin Francis Hunns Jan 1977

Redefinition Of A Syntactic Category In Modern Spanish As A Method Of Facilitating A Computer-Assisted Textual Analysis, Colin Francis Hunns

School of Engineering, Computing and Mathematics Theses

This thesis represents an attempt to produce machinery which will render a computer-assisted textual analysis viable for modern Spanish. To this end, it endeavours to provide a totally new definition for the categorial term "article". The categories of both articles, as traditionally recognized, and those of the concomitant relative pronouns and object pronouns, are subjected to a synoptic analysis based on a consideration of the syntactic, semantic, and morphological features which all these part s of speech have in common. The first chapter defends the categorial status of the indefinite article and deals with the articles in the nounphrase. Chapter …

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X-Ray Structural Studies Of Antibiotic Materials, Richard James Girven Jan 1977

X-Ray Structural Studies Of Antibiotic Materials, Richard James Girven

School of Engineering, Computing and Mathematics Theses

Optimum conditions were devised for the crystallisation of a number of antibiotic s of pharmaceutical interest, and related compounds of particular significance in structure activity investigations. Single crystal X-ray analysis techniques were then used for the determination of the structures of two ß- lactam compounds and an analgesic compound of unusually low physical dependence liability.

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Electron Spin Resonance Morphology And Related Properties Of Selectively Doped Synthetic Kaolinites, K.S. Richards Jan 1976

Electron Spin Resonance Morphology And Related Properties Of Selectively Doped Synthetic Kaolinites, K.S. Richards

School of Engineering, Computing and Mathematics Theses

This thesis is divided into six chapters. The first chapter is an introduction to the structure and properties of natural kaolinites. The second chapter describes the synthesis of kaolinite and a study of various reaction parameters and their effect on the morphology of synthetic kaolinites. Chapters 3 and 4 are devoted to Electron Spin Resonance in natural and doped synthetic kaolinites. Chapter 5 is a study of Fe²˖ and Fe³˖ in kaolinite by Mössbauer spectroscopy. The final chapter consists of a short summary and discussion with some suggestions for future work.

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Application Of Sampling Techniques To The Phase-Controlled Thyristor Cycloconverter, G. A. Hanley Jan 1976

Application Of Sampling Techniques To The Phase-Controlled Thyristor Cycloconverter, G. A. Hanley

School of Engineering, Computing and Mathematics Theses

Low frequency distortion components of the output voltage of a cycloconverter are largely responsible for the restriction on its practical range: of frequencies, and the object of this thesis is to show that these components can be attenuated by the application of sampling techniques to the control system. After a general description of the operation and control of the cycloconverter, the distortion of the output waveform due to low frequency components is discussed. Under these circumstances, the fundamental repetition frequency of the waveform is less than the wanted output frequency, and two methods of determining it for given input and …

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Oxidation Of Lead Sulphide, Peter John Sleeman Jan 1976

Oxidation Of Lead Sulphide, Peter John Sleeman

School of Geography, Earth and Environmental Sciences Theses

Previous research on the precipitation and oxidation of lead sulphide has been reviewed especially in relation to thermodynamic and kinetic studies. Samples of lead sulphide have been precipitated from aqueous solutions of lead salts under varying conditions of pH, concentration, temperature and time of ageing. The precipitates were examined by optical and electron microscopy, X-ray diffraction and gas sorption analysis. Their crystallinity, particle size and phase composition have been correlated with the conditions of precipitation. The oxidation of selected samples of precipitated and commercial lead sulphide was investigated by thermal analysis and the above techniques. The phase composition of the …

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A Conversational Skills Approach To Personal Reconstruction : Longitudinal Studies Using The Repertory Grid, Fraser Reid Jan 1976

A Conversational Skills Approach To Personal Reconstruction : Longitudinal Studies Using The Repertory Grid, Fraser Reid

Other Faculty of Science and Engineering Theses

The aim of this research is to develop a range of procedures for enhancing conversational skills. From a review of theoretical analyses of social encounters a model of conversational process is developed to describe mechanisms by which interactants construct, maintain and revise cognitive models of their social environment. From this model, three dimensions of conversational competence are derived and a training paradigm devised incorporating the process of cognitive reflection by which functional properties of models are displayed to interactants. This paradigm provides a rationale for discrete intervention strategies to effect changes on each dimension of competence. Preliminary studies report attempts …

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The Immune Response Of Plaice With Particular Emphasis On Antigenic Simulation By Tissue Parasites, Barrie J. Cottrell Jan 1975

The Immune Response Of Plaice With Particular Emphasis On Antigenic Simulation By Tissue Parasites, Barrie J. Cottrell

School of Biological and Marine Sciences Theses

Antibody responses to soluble and cellular antigens have been demonstrated in juvenile and adult plaice, Pleuronectes platessa L. A relatively strong precipitating antibody was produced to calf serum, but not to bovine serum albumin. The onset, and magnitude of antibody production was temperature dependant and physico-chemical characterisation of plaice precipitins indicated they were of the IgM class. Plaice also produced haemagglutinins, following injection of rabbit erythrocytes, with a suggestion of a heightened response upon secondary stimulation with the antigen. An evaluation was made of the humoral immune.response of the fish to three tissue parasites; Rhipidocotyle johnstonei and Cryptocotyle lingua, the …

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