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Some ionospheric effects observed at sunrise

  • Authors: Baker, D C
  • Date: 1964
  • Subjects: Sun -- Rising and setting , Ionosphere -- Research
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5513 , http://hdl.handle.net/10962/d1009496 , Sun -- Rising and setting , Ionosphere -- Research
  • Description: The study of the ionosphere over the sunrise period is necessary for an understanding of the vtiriations in layer structure with time and has been a topic of research of many workers. On the whole these investigations have been restricted to a study of critical frequency variations with relatively short intervals of a few minutes between successive records, of N-h curves deduced from ionograms with long intervals (15 minutes or so) between successive N-h curves or of continuously monitored single frequency reflections. Not one of the three techniques is entirely satisfactory for a detailed study of ionospheric behaviour over sunrise. The first two do not give a sufficiently clear indication of what happens in the initial stages of layer development, while from the third incomplete data is obtained as to what is happening at a specific electron-density level. For this reason a preliminary investigation of the ionosphere over sunrise was made at Rhodes University during August, 1959. The records were obtained at four-and-a-half minute intervals and scaled by the method of KELSO (1952 ). "Many of t he results were inconclusive but it appeared that records would have to be taken at approximately one minute intervals and reduced to N-h curves by a scaling technique which made full allowance for low-level ionization if useful results were to be obtained. An attempt has been made in this thesis to investigate the behaviour of the ionosphere over sunrise more fully than can be done by the three techniques referred to. A number of observed phenomena are also examined. Part I deals with the theoretical background to ionosphere physics in general and describes the equipment, equipment modifications and experimental procedure. Part II presents the results obtained. The records for a largescale travelling disturbance are analysed. Various observed phenomena are described and discussed. A simple method of obtaining production rates from experimental data is described. The implications of the observed variations of production rates with height and time are discussed. Suggestions for further research and improvement of the methods used arc made in Charter 9.
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The dramatic theory of William Hazlitt : "Imagination in criticism"

The meaning and connotation of the root [Hebrew characters] in the Old Testament

  • Authors: Craig, Glen Stuart
  • Date: 1964
  • Subjects: Hebrew language -- Roots , Bible -- Criticism, Textual
  • Language: English
  • Type: Thesis , Bachelor , BDiv
  • Identifier: vital:1292 , http://hdl.handle.net/10962/d1014717
  • Description: In Chapter One, mention is made of certain features of Old Testament study which should be kept in view in any study such as this. e.g. The Old Testament is a book about God and His relation to man. It is essentially practical in its thought. The conception of Corporate Personality was very fully developed in Israel, and needs to be borne in mind, particularly for an understanding of pre-exilic Israel. Then, too, the Old Testament Is not homogenous in thought, but is virtually a library of books by different authors, written at different times, and in different circumstances. Chapter Two begins with a brlef survey of the relation of the Hebrew root [Hebrew characters] to other Semitic languages with basic connotations. ThIs is followed by a long and detailed analysis of the use of the root [Hebrew characters] in the Old Testament. In this section, the use of the various grammatical forms - the Verb (Qal, Pi'ēl and Riph'îl), Adjective and Noun, are examined with reference to men and animals, in their metaphorical use and in certain set phrases. Throughout an attempt is made, according the context, to differentiate between its use with the following connotations: being animated, purely physical existence, activity, revival from ill- health, revival from death, and general prosperIty and welfare. The section is concluded with a brief analysis of some words used as parallels to the root [Hebrew characters]. Bearing in mind that the main purpose of this thesis is to try to discover whether, as used in the Old Testament, the root has any deeper significance, an examination is made in Chapter Three of its use in the context of various relationships. After touching briefly on relationships of animals, a detailed study is made of relationships entered into by man; first in a general sense and then more specifically in the context of Election, Covenant, Cultus and Holy Places, as governed by the Torah and finally, as enjoined by Wisdom teachlng. Although relationships between men and other men, and between men and animals, are discussed, the main emphasis is always on the relationship between man and God. The conclusion drawn is that the root [Hebrew characters] is used to denote an intimate relationship between God and man - a relationship though, in which God is by far the more senior partner. Chapter Four is a brief study of the development of a belief in an After-Life in the Old Testament, emphasizing only those aspects which are relevant to the purpose of this Thesis. A brief description of early beliefs in an After-Life is followed by a discussion of tho Prophetic influence and the resistance to any such belief until after the Exile. Post-exilic developments, which took the Hebrews almost to the point of belief in a life after death, are discussed under the headings: "The Problem of Reward and Retribution" and "The Religious need for God". Finally a brief examination is made of the two late passages in the Old Testament where definite reference is made to a life after death. The Root, [Hebrew characters], it is concluded, is used to describe the deepest of all experiences of men - everlasting fellowship with God.
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The meaning and significance of intercessory prayer for the Christian

  • Authors: Young, Ernlé W D
  • Date: 1964
  • Subjects: Prayer , Intercessory prayer , Intercessory prayer -- Christianity
  • Language: English
  • Type: Thesis , Bachelor , BDiv
  • Identifier: vital:1279 , http://hdl.handle.net/10962/d1013439
  • Description: [From Introduction] ‘It is a difficult and even formidable thing to write on prayer, and one fears to touch the Ark. Perhaps no one ought to undertake it unless he has spent more toil in the practice of prayer than on its principle. But perhaps also the effort to look into its principle may be graciously regarded by Him who ever liveth to make intercession as itself a prayer to know better how to pray'. So wrote P.T.Forsyth in the opening chapter of his work on prayer, 1, and at the outset of this study of the meaning and significance of Christian intercession one finds oneself echoing and endorsing his words. Intercession, of course, is only a single aspect of a far greater whole. The whole, to use Francis Thompson's phrase, is a 'many-splendoured thing'. No attempt to define and designate the limits of each of the elements which together make up prayer in its Christian fulness has ever been either entirely satisfactory or generally acceptable. But roughly speaking, there are seven colours on the palette of prayer or, to change the metaphor for one used by Leslie Weatherhead, 2, there are seven rooms in the house of prayer : Affirmation or Invocation of the Divine Presence; Adoration and Praise; Confession and the penitent seeking of Forgiveness, with the Positive Affirmation and Reception of that Forgiveness; Thanksgiving; Petition; Intercession; and Meditation. There are as well the more mystical forms of prayer admirably analysed and distinguished, for example, by Bede Frost.3. In practice, no element can be isolated or divorced from the other elements which with it make up the whole. Affirmation of God's presence issues quite naturally in adoration, which in turn leads spontaneously into confession, and so on. Each aspect of prayer acts and reacts on the others. To single out Intercession (and, insofar as it is related to it, Petition) and to write on it alone would therefore seem to require some explanation.
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The north gap dyke of the Transkei

  • Authors: Moore, Alan C
  • Date: 1964
  • Subjects: Petrology -- South Africa -- Transkei , Dikes (Geology) -- South Africa -- Transkei , Petrofabric analysis -- South Africa -- Transkei
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5031 , http://hdl.handle.net/10962/d1007087
  • Description: Field work and mapping with the aid of aerial photographs have shown the north Gap Dyke to be a vertical intrusion 93½ miles long . It extends from a point about 4½ miles south of Cathcart to the coast where it enters the sea about 100 yards north of the Ngadla R lver mouth. It is composed of several rock types including dolerite pegmatite, granophyric dolerite, subophitic dolerite, and it has a more or less central core of mobilized sediment at the western end. The essential minerals of the dolerite types include zoned plagioclase, which is described in some detail, and augite. Less important are hornblende and micropegmatite. Accessories include apatite, ilmenite, magnetite, quartz, actinolite, prehnite, calcite and epidote. Iddingsite (?), saussurite and chlorite occur as alteration products. The mode of origin of the Gap Dyke magma remains an open question: it may have arisen as a result of normal crystal fractionation or as the result of hybridization in depth followed by differentiation.
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The South Atlantic radiation anomaly

  • Authors: Van Rooyen, H O
  • Date: 1964
  • Subjects: Terrestrial radiation , Atmospheric radiation , Geomagnetism , Electron precipitation , South Atlantic Ocean -- Radiation
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5546 , http://hdl.handle.net/10962/d1013427
  • Description: Part I. (1) An elementary treatment of the motion of charged particles in a magnetic field is presented. The concept of guiding centre motion is introduced, and is used in outlining the theory of particle drifts. (2 ) The motion of charged particles in the geomagnetic field is discussed, and the concept of adiabatic invariance introduced. (3) Mc Iliwains coordinates for mapping the distribution of charged particles trapped in the geometric field are defined and briefly discussed. (4) A survey of present knowledge of the Van Allen radiation zones is made. Particular attention is given to the distribution, characteristics, and variability of the trapped radiation. (5) The Cape Town magnetic anomaly, the Brazil radiation anomaly and the South Atlantic radiation anomaly are discussed. The electrons entering the South Atlantic radiation anomaly are shown to be those monitored over Iowa by the US satellite Injun I. Part 11. (1) It is shown how the geomagnetic field can, at high altitudes and over relatively short distances, be approximated by the field of a monopole. A new method is developed which enables one to plot the energy absorbed from an electron (which moves in a monopole field in the atmosphere) against altitude, given the initial energy and pitch angle of the electron. Some numerical computations using this method are described, and the results discussed. These results are used, in conjunction with US satellite Injun I for the Iowa region, to estimate the energy inout to the atmosphere in the South Atlantic radiation anomaly. The main approximations and simplifying assumptions made in this treatment, are discussed. (2) Geophysical effects generally recognized to be connected with the precipitation of charged particles are discussed. In the course of this discussion the two main theories of the connection between the radiation zones and the auroras are examined. (3) A preliminary discussion, based on the work summarized in point (1) of detectable geophysical events associated with the precipitation of electrons into the South Atlantic radiation anomaly is given. It is concluded that auroral emission, X-ray bursts, and ionospheric ionization in the E region should be more frequent and pronounced in the South Atlantic radiation anomaly than in any other region of comparable invariant latitudes and that the effects of atmospheric heating by precipitated electrons should be detectable over the anomaly. (4) An assessment is made of the value of the method referred to in point (1). Suggestions for its modification and extension are put forward. It is suggested that if more extensive rocket and satellite data on the low energy component of the electron flux become available, this method can be employed in a rigorous theoretical investigation of the South Atlantic radiation anomaly. Summary, p. 98-100.
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The use of certain myths in the work of T.S. Eliot

  • Authors: Hall, R F
  • Date: 1964
  • Subjects: Eliot, T. S. (Thomas Stearns), 1888-1965 -- Knowledge -- Literature , Eliot, T. S. (Thomas Stearns), 1888-1965 -- Criticism and interpretation , Mythology in literature
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2300 , http://hdl.handle.net/10962/d1012129 , Eliot, T. S. (Thomas Stearns), 1888-1965 -- Knowledge -- Literature , Eliot, T. S. (Thomas Stearns), 1888-1965 -- Criticism and interpretation , Mythology in literature
  • Description: T.S. Eliot's statement that myth is an ordering device in literature 'is constantly belied by his use of myth in his own poems'. This is the belief of the American critic Richard Chase, noted for his work on myths and mythological themes in English and American literature. Whether or not Chase is right must emerge from the chapters which follow. The purpose will be to examine the effects of the use of myths and mythological patterns on Eliot's work in general, rather than to annotate individual mythological allusions. Simply to recognise an allusion is to raise a question, not to answer one: for we have then to decide what the writer hope to achieve by its use, and whether or not he has succeeded. Unless they lead on to such questions, lists of sources contribute little to our understanding of a work. Far more important than incidental allusions are the mythological themes and patterns on the larger scale, which reveal themselves in recurrent allusions and in basic patterns of symbolism. Again, merely to recognise such a pattern is inadequate: in every case a discovery of its function in both the poem's (or play's) structure and the poet's technique should be our main concern. ... Eliot himself has made it clear that in his case the use of myths and mythological patterns has often been a fully conscious, even self-conscious process. Therefore we may apply to his work the questions mention by Norman: what functions the myths fulfil within individual works; and why Eliot uses them in the first place. This last question leads us back to a more fundamental one; why do many writers, especially modern ones, use myths 'in the first place'? The problem involves discussion of the relation between myths and literature and of the nature of myths themselves, this forms the material of the first chapter. The other chapters will deal with some of Eliot's works, attempting to explain and analyse his use of myths in them, and to illustrate its importance in each case.
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An investigation into the spelling ability of English-speaking and Afrikaans-speaking pupils in South African schools

  • Authors: Hayward, Fritz Reitz
  • Date: 1963
  • Subjects: English language -- Orthography and spelling -- Study and teaching , Afrikaans language -- Orthography and spelling -- Study and teaching
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1972 , http://hdl.handle.net/10962/d1012238 , English language -- Orthography and spelling -- Study and teaching , Afrikaans language -- Orthography and spelling -- Study and teaching
  • Description: The parlous state in which the English language finds itself in South Africa, both in its written and speech forms, is the cause ot grave concern to most English-speaking citizens, and to many Afrikaans-speaking people as well. This is the case not only in the commercial world and the civll service, but also in the schools and universities, and in fact in most walks of life. Although we are conscious of this state of affairs, and can quote many examples of the poor quality of English used, we have no measuring device through which we can assess exactly how bad the language used by any given group of people is. It is not possible to compare the performance in English of a certain school with standard English and to express the result as a percentage score. The aim of this investigation was to find out how well, or how badly, South African school children spell, and to compare the performances of English- and Afrikaansspeaking pupils. It was felt that the results would provide some concrete evidence and fairly accurate data which could be used to assess the standard of English spelling in our schools, and to pinpoint some of the major weaknesses. The writer hoped, thus, that the investigation might be of some practical usefulness to teachers of English spelling, and as spelling is basic to the written word and to some extent to the spoken word, it might make some small contribution to the drive towards better English in South African schools.
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An investigation of the radio emission by the planet Jupiter on 18 Mc/s & 22 Mc/s

  • Authors: Gruber, Georg Maria
  • Date: 1963
  • Subjects: Radio astronomy , Jupiter (Planet) -- Observations , Radio sources (Astronomy)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5524 , http://hdl.handle.net/10962/d1012113 , Radio astronomy , Jupiter (Planet) -- Observations , Radio sources (Astronomy)
  • Description: This thesis describes the investigation carried out of the radio noise emitted by the planet Jupiter on 18 Mc/s and 22 Mc/s. Chapter I gives a brief introduction and outlines radioastronomical as well as astronomical ideas concerning Jupiter. A detailed survey of the research done to date including some of the hypotheses formulated by previous workers is presented in Chapter II . Chapter III deals with the apparatus used in this research. Two similar sets of apparatus were used. The aerials were folded dipoles. The signals were fed to the receiver, an R 206 , via a 300 ohm impedance line. To increase the gain an extra I -F. stage was included. This gave a gain of better than a 120 dB. To match the signals into the recorder a cathode follower was used. The operating procedure appears in the fourth chapter. The results obtained are discussed and tabulated at the end of the chapter. They agree with the findings made by previous workers, within the experimental limit. Histograms of the occurrence probability versus the revised System III coordinates are presented for each frequency and compared to previous ones. The final chapter contains the author ' s interpretation of the observed effects. A model based on a radiation analogous to the Cerenkov effect is found to be not inconsistent with the available data . Ending the chapter suggestions for further research are made.
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An x-ray investigation of the thermal decomposition of unirradiated and irradiated silver permanganate.

  • Authors: Woods, Geoffrey Steward
  • Date: 1963
  • Subjects: Decomposition (Chemistry) , Materials -- Thermal properties , Solids -- Thermal properties , Permanganates , Silver compounds
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4511 , http://hdl.handle.net/10962/d1013450
  • Description: [From Introduction] The first step in the study of the thermal decompositions of solids is an examination of the kinetics, since this casts much light on the mechanism of the reaction. It must be borne in mind, however, that a theoretical expression, derived on the basis of a particular mechanism, even if it fits the observed experimental results, is not conclusive proof of the validity of the mechanism when applied to the decomposition under examination.
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Aspects of form and style in Beethoven's string quartets

  • Authors: Biesheuvel, Barbara
  • Date: 1963
  • Subjects: Beethoven, Ludwig van, 1770-1827 -- Quartets -- strings
  • Language: English
  • Type: Thesis , Masters , MMus
  • Identifier: vital:2678 , http://hdl.handle.net/10962/d1007645
  • Description: Many books have been written which deal with the subject of form and style in Beethoven's works. Most writers, however, seem to be satisfied with superficial descriptions - in some cases merely programatic - which do not explain the underlying problems and treatment of form. Furthermore, no book exists, to my knowledge, which delves so deeply and with such detail as to deduce with almost certain accuracy the inner coherency of the form. It is the aim of this analysis to approach the problem in this way. The edition used for this purpose is that one published by Ernst Eulenberg Ltd. London WI, which was edited from the autograph M.S. by Professor Dr. Wilhelm Altman. No comparisons are made with other editions, and possible printer's and other errors are not considered. I chose the works to be studied here, the three quartets Op. 59, for two reasons: 1) the string quartet medium is one of the most suitable types of instrumental music for the study of form, 2) the Op. 59 quartets belong to a period in Beethoven's life when he was particularly intent upon experimentation in form and development of dimension.
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Between Renaissance and Baroque: a study of the keybord works of Frescobaldi

Contributions to our knowledge of the biology of Machiloides Delanyi Wygodzinsky and Ctenolepisma Longicaudata Escherich : (Hexapoda Thysanura)

  • Authors: Heeg, J. (Jan)
  • Date: 1963
  • Subjects: Insects -- Adaptation , Insects -- Physiology , Thysanura , Apterygota
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5856 , http://hdl.handle.net/10962/d1012261 , Insects -- Adaptation , Insects -- Physiology , Thysanura , Apterygota
  • Description: Among the South African Thysanura, the order Lepismatoidea has spread over the whole sub-continent, while all except one species of the order Machiloidea are confined to the discontinuous forest belt which lies below the escarpment of the inland plateau. The Machiloidea are not , however, strictly confined to the actual forests within their geographical region, some species invading regions of considerable aridity. Investigations on the ecology, water relations and orientation behaviour of a representative species of each order have been carried out. These have revealed that: (i) the physical conditions in the typical niche of the Machiloidea are extremely stable, whereas those in the habitat of the Lepismatoidea are subject to some considerable fluctuation. (ii) the Lepismatoidea are more resistant to desiccation than the Machiloidea; in both cases this resistance is due in part to physical barriers in the cuticle and partly to an active metabolic process. (iii) the Machiloidea rely on their eversible vesicles, situated on the abdominal coxosternites, for the uptake of water which cannot be drunk, such as a thin film of water or soil capillary water. (iv) the Lepismatoidea are able to absorb water from a subsaturated atmosphere. (v) the behavioural responses of both in respect of humidity, temperature, light and gravity, are such as to keep them in conditions within the range of their physiological limitations. From these results it is concluded that the Machiloidea can survive outside the shelter of forests, provided that water is readily available in some form in which it can be absorbed by the animals. The general implications of the results are such as to permit the erection of an hypothesis explaining the distribution of the Thysanura in South Africa in terms of t he availability of wate. The results also lead to speculations on the evolution of the Pterygota.
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On the physiology of the lantern retractor muscle of Parechinus angulosus

  • Authors: Boltt, R E
  • Date: 1963
  • Subjects: Echinodermata -- Physiology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5900 , http://hdl.handle.net/10962/d1013513
  • Description: From Resumé: The lantern retractor muscles of regular echinoids act in almost isometric conditions and a study of their control was considered to be of interest. The retractor muscles cannot be indirectly stimulated from the radial nerves, but proved to be very photosensitive. Their responses to light were therefore studied. The muscles show a complex pattern of contraction in response to illumination, which includes both excitatory and inhibitory components. The possible genesis of these patterns is discussed and examined in the light of the responses of the muscles to direct current stimulation and to drugs. It is concluded that many of the features of the response are undoubtedly neurogenic in origin, but that myogenic activity may possibly also be involved.
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Prototypes of black wattle tannins and their stereochemistry

  • Authors: Drewes, Siegfried Ernst
  • Date: 1963
  • Subjects: Tannins -- Anthocyanidis Stereochemistry
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4460 , http://hdl.handle.net/10962/d1011437
  • Description: A number of interrelated flavonoid compounds, present in trace quantities in mature black wattle (Acacia mearnsii De Wild) bark, have been isolated and identified for the first time. They include a) the resorcinol-pyrogallol analogues, (+)-leuco-robinetinidin (7,5',4',5'-tetrahydroxyflavan-3,4-diol), dihydrorobinetin (7,5',4',5'-tetrahydroxyflavan-3-ol-4-one) and robtein (2',4',5,4,5- pentahydroxychalcone) and b) the resorcinol-catechol analogues, (+)-leuco-fisetinidin (7,3',4'-trihydroxyflavan-3,4-diol), fustin (7,3',4'-trihydroxyflavan-3-ol-4-one), (-)-fisetinidol (7,3',4'trihydroxyflavan- 3-ol), butein (2',4',3,4-tetrahydroxychalcone) and butin (7,5',4'-trihydroxyflavan-4-one). In addition, two flavonol glycosides, myricitrin (3,5,7,3',4',5'-hexahydroxyflavone-3-rhamnoside ) and quercitrin (5,5,7,5',4'-pentahydroxyflavone-3-rhamnoside), which belong to the phloroglucinol-pyrogallol and phloroglucinolcatechol class of flavonoids respectively, were isolated from immature bark. These represent the only glycosides isolated hitherto from wattle bark or heartwood extracts. Summary, p. i.
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Some properties of a model F1 layer of the ionosphere

  • Authors: De Jager, Gerhard
  • Date: 1963
  • Subjects: Ionosphere , Ionospheric electron density
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5515 , http://hdl.handle.net/10962/d1011046 , Ionosphere , Ionospheric electron density
  • Description: The present work was initially aimed at providing an explanation for some of the phenomena that occur in the ionosphere at sunrise. The approach that was taken was to determine the changes that take place on a theoretical model of the ionosphere and then to compare these with observations. A prerequisite for this approach was a theoretical model that would show, among other things, a bifurcation of the F layer during daytime without making unjustified arbitrary assumptions. The absence of such a model, particularly as far as non-equilibrium conditions are concerned, resulted in the present attempt to provide such a model for the F1 region.
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Studies on certain aspects of the neuromuscular physiology of insects

  • Authors: Moran, V. C. (V. Cliff)
  • Date: 1963
  • Subjects: Insects -- Physiology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5866 , http://hdl.handle.net/10962/d1012879
  • Description: It is well known that high potassium ion concentrations depolarize nervous tissue and it has been suggested that the nerve sheath surrounding the peripheral nerves of insects serves as a protective barrier for the exclusion of potassium ions, in the haemolymph, from the immediate environment of axons. Further it is known that the concentration of potassium ions in the haemolymph of phytophagous insects is far higher than that in predatory forms; this has led to the suggestion that the nerve sheath in plant feeding insects should be more highly developed than that of entomophagous insects. In this work the structure of the nerve sheath in phytophagous and predatory insects has been studied and this assumption has been shown to be groundles. However, preliminary experiments on the effects of ions and drugs on the peripheral nerves of phytophagous and predatory insects have shown that there is a definite difference in susceptibility between the nerves of these two forms and this has led to the postulate of a diffusion barrier beneath the level of the nerve sheath, which is more highly developed in phytophagous than in predatory forms. The properties of this second barrier are discussed. Part 1. , During the course of the work which has been described in Part 1- an outbreak of large saturniid moths Nudaurelia cytherea capensis Stoll.) occurred in the Grahamstown area. It was felt that an investigation into the properties of the flight motor of this moth, which has an extremely low wing beat frquency, might be rewarding as our knowledge of the flight motor in insects is limited to those with very much higher wing beat frequencies than that of this moth. The anatomy, innervation and histology of the flight muscles of Nudaurelia are described and it is shown that the flight motor of this moth is functionally different to that of other insects which have been investigated. Further, Nudaurelia shows a characteristic warm-up fluttering of the wings prior to flight - this phenomenon has also been examined in the following investigation. This study has yielded information about the location of a warm-up centre in the central nervous system of this moth. Part 2.
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Studies on the behaviour of unfed blue tick larvae (Boophilus decoloratus)

  • Authors: Goldsmid, John Marsden
  • Date: 1963
  • Subjects: Boophilus -- South Africa , Ticks -- Behavior -- South Africa , Ticks -- Physiology -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5852 , http://hdl.handle.net/10962/d1012044 , Boophilus -- South Africa , Ticks -- Behavior -- South Africa , Ticks -- Physiology -- South Africa
  • Description: Ticks "are not merely annoying pests but surpass all other anthropods in the number and variety of disease agents for which they are carriers (Chandler 1955). This statement is certainly true of Boophilus decoloratus (Koch), the blue tick, which is probably one of the most important ticks in South Africa. Various studies have been made on the blue tick in Africa, among which are investigations on taxonomy (Hoogstraal 1956); distribution (Theiler 1949 and 1962); ecology (Kraft 1961); disease transmission (Neitz and du Toit 1938; du Toit 1947; Neitz 1956 a and b); control and resistance to insecticides (du Toit, Graf and Bekker 1941; Whitnall and Bradford 1947; Whitehead 1958 and 1959) To date, the behaviour of Boophilus decoloratus has not been studied to any extent. The aim of the present work is to analyse the behaviour of the unfed larvae into its constituent patterns in order to determine what are the significant environmental factors which affect this behaviour. It is also hoped that the present laboratory studies might help in understanding their behaviour in the field. Intro., p. 1.
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Studies on the emulsion scouring of raw wool

  • Authors: Grové, Christo Carel
  • Date: 1963
  • Subjects: Woolen and worsted manufacture
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4479 , http://hdl.handle.net/10962/d1012100 , Woolen and worsted manufacture
  • Description: Knowledge of the mechanism of detergency under various conditions has thus far been built up from laboratory studies. It is well known that the laboratory methods for determing detergency are on the whole not able to give results which agree with those obtained in practice, probably because the actual scouring conditions cannot be duplicated exactly in the laboratory. Detergency testing on a full industrial scale is virtually impossible in view of the high cost and the production losses involved. In commercial raw wool scouring, which is an extremely complex system, it would be very difficult to exercise proper and complete control. The study described here was carried out on a specially constructed pilot plant which is similar to a fullscale plant in that the lengths of the bowls are of the same order as those of industrial plants, but they are considerably narrower. The trials were carried out under strictly controlled conditions in which the effects to be studied were created by the necessary changes while all other factors were kept constant, The pilot plant experiments were planned from indications of laboratory studies and the results were expected to be more comparable with those obtained in industrial practice, The effect of several factors on the scouring of raw wool was studied from the detergent efficiency aspect. The factors investigated were: mechanical action, backflow, temperature and detergency builders. A number of detergents which were selected from the large range which is available were compared with regard to efficiency and economy of scouring. A difficulty which hinders quantitative laboratory work on nonionic detergents is the fact that there is no rapid, accurate method for the estimation of nonionic detergents. The analytical methods which are employed at present are interfered with by virtually all the impurities which are normally present in scouring liquors. Some of the existing methods have been investigated and tested for precision and reproducibility and an attempt was made at establishing a new method. The sorption of nonionic detergents by various substrates has not been fully investigated because of the above reason and also because the amounts of detergent sorbed by most substrates are very small and difficult to determine. Attempts were made at determining the sorption of nonionic detergents onto wool and impurities which are normally found in scouring liquors. A new method for the investigation of "inactivation" of detergent by contaminants present in scouring liquors, which may be regarded as an indirect indication of detergent sorption, was investigated.
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The crystal structure of caesium permanganate by x-ray diffraction

  • Authors: Nassimbeni, L R
  • Date: 1963
  • Subjects: Permanganates -- Crystallography , X-rays -- Diffraction , Crystals -- Piezoelectricity , Pyroelectricity
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4484 , http://hdl.handle.net/10962/d1012942
  • Description: The crystal structure of caesium permanganate has been determined. CsMn0₄ crystallises in the orthorhombic space group Pnma. There are four molecules per unit cell with a = 10.0692 Å, b = 5.8080 Å, c = 7.9470 Å. The structure was determined by Fourier syntheses on the (010) and (001) projections and refined by two-dimensional difference syntheses. The structure is similar to that of KMn0₄. The manganese is surrounded by four oxygen atoms at an average distance of 1.629 Å arranged in a slightly distorted tetrahedron. The caesium is surrounded by eight manganese atoms at an average distance of 4.381 Å.
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