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Static and ultrasonic elastic moduli of wool, mohair and kemp fibres

  • Authors: King, Neville Edwin
  • Date: 1969
  • Subjects: Moduli theory , Mohair , Wool
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5528 , http://hdl.handle.net/10962/d1012640 , Moduli theory , Mohair , Wool
  • Description: Fibres used in textiles can be classified broadly into natural fibres and synthetic fibres. Natural fibres can be either animal, such as wool, mohair and camel hair, or vegetable such as cotton, flax and hemp. In the development of synthetic fibres numerous polymers have emerged which have no real natural counterpart and are unique in their mechanical and chemical behaviour. Often the synthetic counterpart of a natural fibre has properties with certain advantages from the textile point of view, but, simultaneously, may exhibit other properties which have disadvantages. Nylon 6 and nylon 6-6, for exemple, are extremely strong and generally easier to dye than animal fibres. On the other hand, they absorb relatively little water vapour and therefore do not give the buffering action characteristic of hygroscopic fibres, once they are woven or knitted into cloth. All textile fibres belong to the chemical class of polymers, i.e. they are made up of repeating molecular units which are linked together to form long chains. In wool the chains are made up of amino-acids which cluster together to form protein chains. Three of these protein chains, coil around each other to form what is termed a proto-fibril. The proto-fibrils make up the micro-fibrils, each of these consisting of eleven of the three chain proto-fibrils. The micro-fibrils, in turn, pack together in bundles which run parallel to the length of the wool fibre and are termed macro-fibrils. Sulphur rich amino-acids fill up the spaces between the micro-fibrils forming a matrix which binds the system into a continuous material. Intro., p. 1.
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  • Date Issued: 1969

Studies on the ecology and systematics of the diatoms (Bacillariophyta) from some South Africa rivers

  • Authors: Archibald, Robert Eldred Mostert
  • Date: 1969
  • Subjects: Diatoms -- Ecology -- South Africa , Diatoms -- Classification , Aquatic ecology -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4098 , http://hdl.handle.net/10962/d1009494 , Diatoms -- Ecology -- South Africa , Diatoms -- Classification , Aquatic ecology -- South Africa
  • Description: This report contains the results of some ecological and systematic studies on the diatoms from the Vaal Dam catchment area in the Transvaal, and the Bloukrans River in the Eastern Cape Province. In Part 1 the effects of high concentrations of nitrogen were studied in relation to the composition of the diatom associations. Water samples from four stations on the Bloukrans River were analysed chemically at certain intervals during the months of April and August 1967. Diatom samples collected from these stations at the beginning and end of each of these sampling periods were subjected to a "Thomasson Analysis" to determine the relative densities of the various species in the diatom associations. A statistical analysis of the results reflected a poor but positive correlation between the two variables, i.e. high numbers of nitrogen heterotrophic Nitzschiae were correlated with high concentrations of nitrogen, while low numbers were correlated with low concentrations. Part 2 presents the results of the ecological studies on the diatom associations of the Vaal Dam Catchment Area. In this section the diatom associations from each sampling point or station were subjected to a "Thomasson Analysis" to determine the relative densities of the different species in the associations. Employing already known correlations between environment and association, the results of this analysis were discussed and the ecological conditions for each sampling station were assessed. The associations were similar in composition over the entire catchment area, and indicated on the whole water of good quality. Points of pollution were detected, but were generally localised and the effects of the pollution were soon removed. Only the Waterval River showed evidence of more constant pollution. The associations provided evidence for some seasonal variation in their composition. Finally in Part 3 the systematics and taxonomy of the diatoms in the Vaal Dam catchment area are discussed. References are made to the original and more recent descriptions of each species found in this study, and a list of synonyms is given wherever 'possible. Comments on the systematics, taxonomy and autecology of each species are given, and the distribution of the species in South Africa and the Vaal Dam catchment area is discussed. A number of species, varieties and forms have been recorded for the first time in South Africa. During the course of this study 20 species have been described as new to science; the descriptions of some have been published, while the descriptions of the others will be published formally in the future. All species described as new or having interesting features are illustrated in the plates.
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  • Date Issued: 1969

The amphibolite at Chibuluma Mine Zambia

  • Authors: Thomson, Iain Dennis
  • Date: 1969
  • Subjects: Amphibolite -- Zambia
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5066 , http://hdl.handle.net/10962/d1013391
  • Description: Chibuluma Mine is situated on the southern flank of the Nkana-Chambishi basin in the central section of the Zambian Copperbelt. The amphibolite at Chibuluma Mine occurs exclusively in the Upper Roan Group sediments overlying the economically important Lower Roan Group. The amphibolite occurs in lenticular, sill-like bodies ranging in thickness from less than 10 feet to over 1,000 feet. It is concluded that these sill-like bodies are intrusive sills of basic magma. The largest sill is a multiple intrusion with two phases, both of which exhibit chilled margins. The younger phase was intruded into the older along a plane approximately 50 feet above its basal contact. Grainsize, specific gravity, and micrometric data indicate that each phase of the intrusion has undergone gravitational differentiation during crystallisation. Variations in the relative amounts of amphibole and feldspar distinguish between a lower melanocratic amphibolite, an upper mesotype amphibolite, and a zone of coarse-grained pegmatitic amphibolite schlieren. The amphibolite consists mainly of hornblende, labradorite, albite, and scapolite, with accessory biotite, chlorite, epidote, clinozoisite, sphene, apatite, quartz, micropegmatite, and calcite. Clouding of the basic plagioclase and zoning in amphibole, plagioclase, and scapolite are features of petrological significance. The opaque minerals in the amphibolites and the adjacent sediments are magnetite, ilmenite, pyrite, chalcopyrite, pyrrhotite, cubanite, valleriite, and pentlandite. Intergrowths of these suggest that their temperatures of formation were probably in excess of 450°C. The chemical data show a close resemblance between the amphibolite and a tholeiitic magma-type although minor spilitic characteristics are also evident. The chemical data also confirm the mineralogical evidence of fractionation and gravitational differentiation. The trend in differentiation followed in the development of the pegmatitic and mesotype amphibolite is very similar to the trends followed by other basic intrusions. The main metamorphic affect accompanying the intrusion of the amphibolite is the soda metasomatism evident in both sediments and intrusions. Some evidence exists to suggest that the amphibolites were emplaced before or during the early stages of the Lufilian orogeny when sediments were essentially horizontal.
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  • Date Issued: 1969

The case of James Erith, 1820 settler, and his struggle for compensation

  • Authors: Woods, Timothy Phillips
  • Date: 1969
  • Subjects: Erith, James, 1790-1869 , British settlers of 1820 (South Africa) , Cape of Good Hope (South Africa) -- Emigration and immigration
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2618 , http://hdl.handle.net/10962/d1013451
  • Description: James Erith, a freeholder of the country of Kent, was one of the “1820 Settlers" who emigrated to the Cape and were settled mainly in the Zuurveld in the present district of Albany. This investigation was prompted by the fact that though he was by no means the settler to suffer misfortune and injustice, he was the only proprietor of a small party who eventually secured compensation. The case was the case of James Erith but the initiative and persistence was that of his wife, Jane Erith, who made in all five voyages spread over twelve years, before she secured some at least of the ends she sought and the family settled in Cape Town. The Eriths fought their case with the respective Colonial Offices for twelve years in all, and in the case of the Colonial Office, London, confronted no less than four Secretaries of State in five successive Cabinets. In the course of their struggle the Eriths received (a) the balance of their deposit; (b) cash compensation for cattle stolen by the Xhosa, and in the fina1 arbitration in 1832 the sum of £500 cash. James Erith, master baker, remains a rather shadowy figure, sharp-sighted to his own interest, querulous and not very effective. The triumph of 1832 was in the main the triumph of Jane, his wife, an amateur and robust Portia. Shrewd, tenacious, deft in argument this importunate woman knew how to stand her ground; there can have been few women who secured passage on a naval vessel and then allowed the Admiralty to submit its account to the Colonial Office. How the Eriths subsisted between their eviction from Waaye Plaats in 1823 and the arbitration award of 1832, has not been established. On occasion in London Mrs. Erith stayed with the Rev. R. Stewarts, Rutland House, Black Heath Road in Greenwich: in Cape Town it is believed that Erith plied his old trade. When he died there, in 1869 at the age of seventy nine, he left a house and three cottages to his daughter Ellen: mortgaged property in the district of Caledon, to his son-in-law George Budge : a house and three mortgaged properties in Simon’s Town to his daughter Anne Budge. He left an income of £24 per annum to his daughter Jane Moodie, widow of the late John Powell. The records used in this study, in addition to those printed in Theal, were the series C.O. 48 from the Public Record Office, London, now available on microfilm in the Cory Library at Rhodes University and records of the District of Albany in the Archives, Cape Town. The investigation has, it is thought, thrown new light on the background to the emigration scheme of 1819, on the mishandling of the Settlers in the Zuurveld after their arrival in the Cape, and on the punctilious attention to detail given by the Colonial Office, London. While it is true that the interests of the Eriths were probably smothered in the Tory endeavour to damp down the attack on Somerset in l826-1827, the Secretaries of State are by no means discredited by this analysis. It sasys much for any pattern of administration that in the thick of the Reform Bill crisis, the efforts of a single obscure member of Parliament, Mr. J O Briscoe, could secure a final arbitration award.
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  • Date Issued: 1969

The geology of a portion of north-western Albany

  • Authors: Wright, Alexander Ross
  • Date: 1969
  • Subjects: Geology -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5068 , http://hdl.handle.net/10962/d1013440
  • Description: [Introduction] During 1965 the author, in looking for a project for a thesis to be submitted for the degree of Master of Science in Geology, decided to map a suitable region in order to gain experience in geological field work. The exact nature of the region itself was of no great importance, but since this study was to be conducted through Rhodes University, it was decided that an area, as near to Grahamstown as possible, would be the most suitable. With this in view, the geologist in charge of the Grahamstown Office of the Geological Survey was invited to suggest an area suitable for study, and if possible, to obtain financial assistance. He indicated the region which has been mapped and which will eventually form part of the proposed sheet 143. It is immediately adjacent to, and to the west of the 1:125,000 sheet 136 of Grahamstown completed by Mountain in 1940.
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  • Date Issued: 1969

The growth of flue-cured tobacco in acid soils

  • Authors: Ryding, William Wallace
  • Date: 1969
  • Subjects: Flue-cured tobacco -- Zimbabwe , Acid soils -- Zimbabwe
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4495 , http://hdl.handle.net/10962/d1013110
  • Description: The main effects of lime, aluminium, iron and manganese were studied in field and greenhouse grown tobacco; relations between soil and plant measurements were examined. Ground limestone, ground mixed lime, ground dolomite and slaked lime at rates equivalent to 1,000 and 2,000 lb. CaC0₃/acre increased yield and quality of flue-cured tobacco both on Triassic and granite sands, whether applied early (February/March) or late (September); the highest rate and late application were often best. Yields increased with 4,000 and 6,000 lb. dolomite/acre applied late, but quality decreased when the pH was about 6.0. Lime did not affect leaf maturity as reflected by nitrogen and reducing sugars concentration . Where leaf discolouration (slate) occurred, the best quality and least discoloured leaf had the lowest manganese concentration and was grown on limed soil. On a very acid and probably nitrogen deficient soil, lime, borax and nitrogen (nitrate only tested) reduced the discolouration and improved the quality, but potassium sulphate increased discolouration and decreased quality. Calcium concentration in the leaf was increased by lime, particularly calcitic materials, and magnesium concentration was increased by dolomite. Lime also increased the filling value and petroleum ether extract, but decreased manganese, boron, chloride and sometimes potassium, and had no effect on phosphorus, nitrogen, aluminium, iron, crude fibre, nicotine, reducing sugars and equilibrium moisture. The inorganic composition of greenhouse plants was similar; generally gypsum increased calcium concentration more than calcium carbonate but it did not affect manganese concentration, which was decreased by calcium carbonate. In the stem and roots of field grown plants (dolomite only tested), the concentration of magnesium was increased but the concentrations of calcium, potassium, aluminium and iron were unaffected. Although the concentration of nitrogen was increased and that of phosphorus was decreased in the stem, these were unaffected in the roots. Aluminium and iron behaved differently to other nutrient ions, being more concentrated in the roots than aerial plant parts. Boron and magnesium deficiencies were observed in a dry and wet year, respectively, suggesting that variable mineral deficiencies can affect responses to lime. Initially soil pH was affected more by source of lime, but later mostly by rates. Slaked lime increased the soil pH more than did ground limestone, mixed lime or dolomite. In a glasshouse experiment, pH was more important than calcium supply and in the field, the largest yields were often associated with the highest pH. In pot experiments, aluminium drastically reduced yields in nutrient solution but not in soils, whereas iron was more severe in soils; manganese had little effect on yield. Manganese was readily taken up and translocated to the tops, but aluminium and iron were mainly concentrated in the roots, as was found in field grown plants. Iron decreased manganese concentration in all plant parts and aluminium decreased calcium and manganese in nutrient solution only. Although aluminium and iron generally increased the concentration of phosphorus in the roots, they did not interfere with phosphorus transport in the plant. Manganese caused the leaf to become chlorotic and when no iron was present the upper leaves became yellow, and developed brown and white lesions. However, in soil grown plants, sufficient iron was present in the soil solution to prevent break down of tissue. Yellowing of the upper leaves also occurred when plants were grown in nutrient solution with aluminium and no iron; when both were present, the plants were darker in colour. Although aluminium damaged roots in nutrient solution, high rates of iron severely damaged leaves of plants grown in soil. Since the concentrations of aluminium, iron and manganese were decreased in the soil solution by liming, they were compared with plant growth and composition in 17 different soils, with and without lime. As was expected, lime increased soil pH. It also increased exchangeable calcium, but decreased exchangeable aluminium, iron and manganese; exchangeable magnesium and potassium and resin extractable phosphorus were not affected. As the Ratio Law does not hold for all Rhodesian soils, anion adsorption will be avoided if the soils are equilibrated with O.OOOSM CaC1₂; the concentrations of the cations in solution were affected in the same way as exchangeable cations, but phosphorus was increased. There was no relationship between yield of tobacco and its chemical composition. The correlations between soil solution data and plant composition were poor, except for manganese and phosphorus; the relation between Mn ppm. in plant vsa (superscript)Mn/a (superscript)Ca + Mg (enclosed in square root sign √) in solution, and P% vs pH₂ P0₄ or pH₂ P0₄ +½ pCa, were both curvilinear. On the other hand, all measurements of exchangeable cations were poorly correlated with plant composition. Finally yield was poorly correlated with soil solution data, and pH was as satisfactory as any other measurement tested. Manganese toxicity was observed on three soils, and a probable manganese deficiency on one. It was not possible to define a limit above which manganese toxicity occurred, but manganese deficiency developed at about 63 ppm. manganese. Variations in pH and the availability of aluminium, iron and manganese occurred when soils were incubated at about field capacity, generally the main effects having developed within seven days. In all soils, there was an initial increase in soil pH and a maximum value was reached in one to four days, decreasing by variable amounts with longer periods of incubation. Although the concentration of aluminium was larger than that of iron, the relation between both ions and soil pH was curvilinear, their concentrations increasing with decreasing pH. Increased temperature of incubation increased pH with a resultant decrease in the concentration of aluminium, but in one soil it appreciably increased the availability of iron in the early periods of incubation. Autumn and spring ploughing did not affect subsequent pH or the concentration of aluminium and iron in the soil solution. Manganese concentration varied from soil to soil and was not related to soil pH. In most soils there was a decrease in manganese concentration with length of incubation and it decreased more rapidly the lower the initial concentration. Temperature effects were variable and moisture affected the behaviour of manganese more than temperature. These findings and the distribution of aluminium, iron and manganese in the plant helped to explain the poor correlations.
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  • Date Issued: 1969

The ideals of consciousness and conduct in Henry James's The Ambassadors and The Golden Bowl

  • Authors: Bryer, Lynne
  • Date: 1969
  • Subjects: James, Henry, 1843-1916. Ambassadors , James, Henry, 1843-1916. Golden bowl
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2321 , http://hdl.handle.net/10962/d1014635
  • Description: The mature work of Henry James gives the fullest expression of certain ideals which I have called the ideals of consciousness and conduct. These ideals are the subject of this thesis. As they are best illustrated in the two novels The Ambassadors (1903) and The Golden Bowl (1904), I have first analysed these books in detail. Though emphasising "theme" rather than "techniques" (I make the usual working distinction while recognising its limitations), I have also attempted to show how intimately James's technique is related to his exploration of consciousness and conduct. In Part Three I have tried to gather up ideas arising from the analyses of The Ambassadors and The Golden Bowl to compare them, expand on them and generalise from them. In this way I have arrived at conclusions that may help to interpret mature vision of James.
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  • Date Issued: 1969

The Patchway Gold Mine : a mineragraphic and petrographic examination of ore from the Patchway Gold Mine, Rhodesia, and an appraisal of the relationship between gold mineralisation and geological structure

  • Authors: Ward, J H W
  • Date: 1969
  • Subjects: Gold ores -- Geology -- Zimbabwe , Petrology -- Zimbabwe , Geology -- Zimbabwe , Ores -- Zimbabwe , Gold mines and mining -- Zimbabwe
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5069 , http://hdl.handle.net/10962/d1013471
  • Description: A remarkable correlation between hydrothermal gold mineralisation and geological structure is discussed. The mineralisation occurs in vein quartz which occupies a fissure in Archaean greenstones of the Basement Complex in Rhodesia, It has been determined that gold which is silver-rich is typical of low-grade ore, and is associated in space with sulphides that crystallised early in paragenesis. Silver-poor gold is characteristic of highgrade ore which is concentrated along the crestal zone of anticlinal warps in the fissure. It is suggested that the local pattern of fracturing and folding is related to fundamental wrench faulting.
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  • Date Issued: 1969

The production and marketing of South African Maize since 1910, with special reference to the years 1954 to 1966

  • Authors: Brits, Rudolph Nieuwoudt
  • Date: 1969
  • Subjects: South Africa. Maize Board , Corn industry -- South Africa , Corn -- South Africa -- Marketing , Corn -- South Africa -- Marketing -- Government policy
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:1104 , http://hdl.handle.net/10962/d1013386
  • Description: From Introduction: There is no evidence available that maize was known in the old world in ancient times. Seeds of barley and wheat have been found in ancient near eastern sites, but never has there been any trace of maize at all. Furthermore, maize as a plant is not mentioned in the Bible, and neither Greek nor Chinese literature makes any reference to maize. There is, therefore, nothing that suggests that maize was known in the Old world before about 1492. However, at that time, Christopher Columbus returned with a report about a new grain called "Maiz". At a later date explorers visiting America found that maize was being grown and consumed by the Red Indians in places as far apart as Canada and Chile. The consensus of opinion is, therefore, that maize originated in America and was only subsequently imported into Europe. However, in a very excellent paper, Dr. M.D.W. Jeffreys comes to the very convincing conclusion that "Maize, a non-self-propagating American plant, was introduced to east African littorals before the Portuguese rounded the Cape and was seen by the Chinese navigators at Melinde Circa 1414… Maize was brought to the Indian Ocean littorals by Arabs before 1400. Maize was brought into southern Africa by the Nguni by 1400 and later by the baVenda. Maize was introduced by the Dutch in 1658. There is no evidence that maize was introduced by the Portuguese. Irrespective of the exact date when maize was introduced into South Africa, it was only from the year 1840 that there was any real agricultural development in South Africa. At this date, all those who had participated in the Great Trek had more or less settled down, and substantial areas were planted with wheat, maize and oats.
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  • Date Issued: 1969

The theory and practice of "Klangreihenkomposition"

  • Authors: Nowotny, Norbert W
  • Date: 1969
  • Subjects: Hauer, Josef Matthias, 1883-1959 , Music theory , Twelve-tone system , Musical intervals and scales , Tonality
  • Language: German
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:2693 , http://hdl.handle.net/10962/d1013394
  • Description: Diese Arbeit befaßt sich mit der "Klangreihenlehre'', einer Musiktheorie, die von Josef Matthias Hauer aufgestellt und von meinem Lehrer Othmar Steinbauer weiterentwickelt wurde. Diese auf der Gesetzmäßigkeit der zwölf Töne beruhende Satzlehre hat jedoch mit der "Reihentechnik" jener Musik, die schlechthin als "Zwölftonmusik" bezeichnet wird, nichts gemein. Obwohl eine beachtliche Literatur über J.M. Hauer vorliegt, ist sie doch, was Hauers Musiktheorie betrifft, nicht zufriedenstellend, da sie hauptsächlich auf sein Leben und seine Musikphilosophie eingeht.
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  • Date Issued: 1969

The theory of economic underdevelopment and its applicability to the Rhodesian economy

  • Authors: Clarke, Duncan G, 1948-
  • Date: 1969
  • Subjects: Zimbabwe -- Economic conditions , Economic development -- Zimbabwe , Developing countries -- Economic conditions
  • Language: English
  • Type: Thesis , Honours , BCom
  • Identifier: vital:1114 , http://hdl.handle.net/10962/d1014691
  • Description: According to the canons of conventional economic philosophy the process of economic interpretation should be value neutral and strictly fall within the bounds of normative science. This approach is concerned not with goal setting but only with the technical possibilities of alternative means of successful tactics in a given overall strategy. It is the author's thesis that such premises patently ignore the fundamental truths of development problems, and that there exists a genuine need to bridge the gap that demarcates theory from practicality and truth from illusion. To seek "development" implies a challenge to the "status quo" of menial existence and perpetual servitude to the inhospitable forces of ones own environment. This attitude is in itself a value judgement, and in underdeveloped societies it is more than a mere academic quibble. Accordingly, this paper not only implicitly assumes "development" to be a desirable goal but also that it is necessary, and the objective of this study of an underdeveloped community shall be to examine the theoretical relevance, or otherwise, of general and partial theories of underdevelopment against the quantitative and qualitative evidence of the course of events that have in the past, and are likely in the future, to influence the development of the "Rhodesian economy".
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  • Date Issued: 1969

Theoretical aspects of the reaction of zirconium compunds and vegetable tannins with the chromium-collagen complex

  • Authors: Williams-Wynn, David Ernest Arthur
  • Date: 1969
  • Subjects: Zirconium compounds , Collagen , Chromium compounds , Tannins
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4512 , http://hdl.handle.net/10962/d1013455
  • Description: Studies have been made of the reactions which take place when zirconium compounds and vegetable tannins react with chromium tanned leather, in order to elucidate the mechanisms of the reactions which occur on retannage. Statistical procedures have been used in all investigations because of the variable nature of the substrate, and computer techniques have been applied to the repetitive statistical computations. Although chromium and vegetable tannages are well understood, further information on the reaction of zirconium with collagen was necessary before attempting to interpret the results of the studies of combination tannages with chromium, and this has been obtained by a comparative study of the reactions of chromium and zirconium with modified collagen. It is concluded that the mechanism of the reaction of basic zirconium sulphate with collagen is multipoint attachment of the tanning material by residual valency forces, although charge effects with basic groups may be supplementary. Zirconyl chloride reacts with carboxyl groups but does not form satisfactory, stable cross-links with collagen. Further evidence for this theory was obtained from the investigation of the reaction of zirconium compounds with chromium tanned collagen. Zirconyl sulphate does not interfere with effective chromium tannage and therefore can have little affinity for the carboxyl groups on the protein, but it displaces chromium complexes loosely held by auxiliary valencies without reducing the shrinkage temperature of the chromium leather Zirconyl chloride, although only fixed to a limited extent, apparently forms co-ordination compounds with the carboxyl groups, disrupting the chromium tannage because there is an over-all loss of hydrothermal stability. There is no evidence that zirconium co-ordinates with, or releases acid from chromium-collagen complexes, since combination chromium/zirconium tanned leathers are stable on storage. Retannage of chromium tanned leather with vegetable tanning materials generally results in loss of strength and a product which tends to deteriorate on ageing. Lower initial strength is probably due to the increased avidity of chromium tanned pelt for vegetable tannins, resulting from the liberation of internally neutralised reactive sites which are not normally available in vegetable tannage, and from the co- ordination of vegetable tannins and non-tannins to the chromium complex with the displacement of sulphate radicals. From a study of the retannage of chromium tanned modified collagen, it appears that basic groups probably play an important part in the rapid absorption of vegetable tannin. These reactions result in overloading of the fibre and an increased number of cross-links, both of which tend to produce weak leather. Deterioration with age is primarily a hydrolytic degradation of the protein which is catalysed by acid liberated from the chromium complexes by the entry of vegetable tannins, those factors which favour the formation of acid causing greater and more rapid deterioration.
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  • Date Issued: 1969

Wood-wind instruments at the cross-roads : a survey of recent changes

  • Authors: Honey, Albert Edward
  • Date: 1969
  • Subjects: Woodwind instruments Woodwind instruments -- History
  • Language: English
  • Type: Thesis , Masters , MMus
  • Identifier: vital:2685 , http://hdl.handle.net/10962/d1012331
  • Description: Since the rise of the "Stile Rappresentative" early in the seventeenth century, the composer has made definite and increasing demands on specific performance and tonal combination of instrumentalists which has materially affected the developnent in technique and, consequently, the improvement in construction and design of every musical instrument. The monodic "Stile Rappresentative" required expressive instruments with an extensive range to match the singers and, consequently, many instruments of the Renaissance period were rendered obsolescent. For instance, the shawms, pommers and crumhorns disappeared from concerted music-making with the exception of military and outdoor use, mainly in German windbands. More flexible instruments were required, and thus cornetts, flutes (mainly recorders and fipple-flutes), oboes and bassoons came gradually into their places, which for the main part they have occupied in the orchestra ever since that time. The String sections, too, underwent radical changes. A gradual metamorphosis from the Consort of Viols to the Violin Family took place following the work of the craftsmen Gasparo da Salố (1540 - 1609) and Giovanni Paolo Maggini of Brescia, perfected by the famous Cremonese school founded by Andrea Amati and continued by Stradivarius.
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  • Date Issued: 1969

Rhodeo, Vol. 22, No. 21

  • Date: 1968-10-10
  • Subjects: Grahamstown -- Newspapers , Journalism, Students -- South Africa , Rhodes University -- Activate , Rhodes University -- Students , Student newspapers and periodicals -- South Africa
  • Language: English
  • Type: Text
  • Identifier: vital:14595 , http://hdl.handle.net/10962/d1019467
  • Description: Rhodeo is the Independent Student Newspaper of Rhodes University. Located in Grahamstown, Rhodeo was established in 1947, and renamed in 1994 as Activate. During apartheid Rhodeo became an active part of the struggle for freedom of expression as part of the now defunct South African Student Press Union. Currently Activate is committed to informing Rhodes University students, staff and community members about relevant issues, mainly on campus. These issues range from hard news to more creative journalism. While Activate acts as a news source, one of its main objectives it to be accessible as a training ground for student journalists. The newspaper is run entirely by the students and is published twice a term. Activate is a free newspaper which receives an annual grant from the Rhodes University Student Representative Council, however, majority of its revenue is generated through advertising.
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  • Date Issued: 1968-10-10

Rhodeo, Vol. 22, No. 20

  • Date: 1968-09-19
  • Subjects: Grahamstown -- Newspapers , Journalism, Students -- South Africa , Rhodes University -- Activate , Rhodes University -- Students , Student newspapers and periodicals -- South Africa
  • Language: English
  • Type: Text
  • Identifier: vital:14594 , http://hdl.handle.net/10962/d1019466
  • Description: Rhodeo is the Independent Student Newspaper of Rhodes University. Located in Grahamstown, Rhodeo was established in 1947, and renamed in 1994 as Activate. During apartheid Rhodeo became an active part of the struggle for freedom of expression as part of the now defunct South African Student Press Union. Currently Activate is committed to informing Rhodes University students, staff and community members about relevant issues, mainly on campus. These issues range from hard news to more creative journalism. While Activate acts as a news source, one of its main objectives it to be accessible as a training ground for student journalists. The newspaper is run entirely by the students and is published twice a term. Activate is a free newspaper which receives an annual grant from the Rhodes University Student Representative Council, however, majority of its revenue is generated through advertising.
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  • Date Issued: 1968-09-19

Rhodeo, Vol. 22, No. 19

  • Date: 1968-09-12
  • Subjects: Grahamstown -- Newspapers , Journalism, Students -- South Africa , Rhodes University -- Activate , Rhodes University -- Students , Student newspapers and periodicals -- South Africa
  • Language: English
  • Type: Text
  • Identifier: vital:14593 , http://hdl.handle.net/10962/d1019465
  • Description: Rhodeo is the Independent Student Newspaper of Rhodes University. Located in Grahamstown, Rhodeo was established in 1947, and renamed in 1994 as Activate. During apartheid Rhodeo became an active part of the struggle for freedom of expression as part of the now defunct South African Student Press Union. Currently Activate is committed to informing Rhodes University students, staff and community members about relevant issues, mainly on campus. These issues range from hard news to more creative journalism. While Activate acts as a news source, one of its main objectives it to be accessible as a training ground for student journalists. The newspaper is run entirely by the students and is published twice a term. Activate is a free newspaper which receives an annual grant from the Rhodes University Student Representative Council, however, majority of its revenue is generated through advertising.
  • Full Text:
  • Date Issued: 1968-09-12

Rhodeo, Vol. 22, No. 18

  • Date: 1968-09-05
  • Subjects: Grahamstown -- Newspapers , Journalism, Students -- South Africa , Rhodes University -- Activate , Rhodes University -- Students , Student newspapers and periodicals -- South Africa
  • Language: English
  • Type: Text
  • Identifier: vital:14592 , http://hdl.handle.net/10962/d1019464
  • Description: Rhodeo is the Independent Student Newspaper of Rhodes University. Located in Grahamstown, Rhodeo was established in 1947, and renamed in 1994 as Activate. During apartheid Rhodeo became an active part of the struggle for freedom of expression as part of the now defunct South African Student Press Union. Currently Activate is committed to informing Rhodes University students, staff and community members about relevant issues, mainly on campus. These issues range from hard news to more creative journalism. While Activate acts as a news source, one of its main objectives it to be accessible as a training ground for student journalists. The newspaper is run entirely by the students and is published twice a term. Activate is a free newspaper which receives an annual grant from the Rhodes University Student Representative Council, however, majority of its revenue is generated through advertising.
  • Full Text:
  • Date Issued: 1968-09-05

Rhodeo, Vol. 22, No. 17

  • Date: 1968-08-29
  • Subjects: Grahamstown -- Newspapers , Journalism, Students -- South Africa , Rhodes University -- Activate , Rhodes University -- Students , Student newspapers and periodicals -- South Africa
  • Language: English
  • Type: Text
  • Identifier: vital:14591 , http://hdl.handle.net/10962/d1019463
  • Description: Rhodeo is the Independent Student Newspaper of Rhodes University. Located in Grahamstown, Rhodeo was established in 1947, and renamed in 1994 as Activate. During apartheid Rhodeo became an active part of the struggle for freedom of expression as part of the now defunct South African Student Press Union. Currently Activate is committed to informing Rhodes University students, staff and community members about relevant issues, mainly on campus. These issues range from hard news to more creative journalism. While Activate acts as a news source, one of its main objectives it to be accessible as a training ground for student journalists. The newspaper is run entirely by the students and is published twice a term. Activate is a free newspaper which receives an annual grant from the Rhodes University Student Representative Council, however, majority of its revenue is generated through advertising.
  • Full Text:
  • Date Issued: 1968-08-29

Rhodeo, Vol. 22, No. 16

  • Date: 1968-08-22
  • Subjects: Grahamstown -- Newspapers , Journalism, Students -- South Africa , Rhodes University -- Activate , Rhodes University -- Students , Student newspapers and periodicals -- South Africa
  • Language: English
  • Type: Text
  • Identifier: vital:14590 , http://hdl.handle.net/10962/d1019462
  • Description: Rhodeo is the Independent Student Newspaper of Rhodes University. Located in Grahamstown, Rhodeo was established in 1947, and renamed in 1994 as Activate. During apartheid Rhodeo became an active part of the struggle for freedom of expression as part of the now defunct South African Student Press Union. Currently Activate is committed to informing Rhodes University students, staff and community members about relevant issues, mainly on campus. These issues range from hard news to more creative journalism. While Activate acts as a news source, one of its main objectives it to be accessible as a training ground for student journalists. The newspaper is run entirely by the students and is published twice a term. Activate is a free newspaper which receives an annual grant from the Rhodes University Student Representative Council, however, majority of its revenue is generated through advertising.
  • Full Text:
  • Date Issued: 1968-08-22

Rhodeo, Vol. 22, No. 15

  • Date: 1968-08-15
  • Subjects: Grahamstown -- Newspapers , Journalism, Students -- South Africa , Rhodes University -- Activate , Rhodes University -- Students , Student newspapers and periodicals -- South Africa
  • Language: English
  • Type: Text
  • Identifier: vital:14589 , http://hdl.handle.net/10962/d1019461
  • Description: Rhodeo is the Independent Student Newspaper of Rhodes University. Located in Grahamstown, Rhodeo was established in 1947, and renamed in 1994 as Activate. During apartheid Rhodeo became an active part of the struggle for freedom of expression as part of the now defunct South African Student Press Union. Currently Activate is committed to informing Rhodes University students, staff and community members about relevant issues, mainly on campus. These issues range from hard news to more creative journalism. While Activate acts as a news source, one of its main objectives it to be accessible as a training ground for student journalists. The newspaper is run entirely by the students and is published twice a term. Activate is a free newspaper which receives an annual grant from the Rhodes University Student Representative Council, however, majority of its revenue is generated through advertising.
  • Full Text:
  • Date Issued: 1968-08-15
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