List of Titles

The polarographic determination of trace elements in blister and refined copper

Authors: Eve, Adrian John
Date: 1954
Subjects: Copper , Polarographs , Polarography
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4467 , http://hdl.handle.net/10962/d1011769 , Copper , Polarographs , Polarography
Description: In the complete analysis of copper the following impurities are generally determined: silver, gold, lead, arsenic, antimony, selenium, tellurium, iron, zinc, cobalt, nickel, oxygen, sulphur, and, less commonly, tin and phosphorus. The actual copper content varies around 99.0% in blister copper; in the refined metal the content is somewhat higher, usually over 99.9%. The concentrations of the individual impurities vary from tenths to thousandths of one per cent.
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Date Issued: 1954

The rehabilitative value of sub-economic housing as illustrated by Schauder Township, Port Elizabeth, Cape Province, Union of South Africa, 1938-1948

- Stoker, F M L

Authors: Stoker, F M L
Date: 1954
Subjects: Housing rehabilitation -- South Africa -- Port Elizabeth
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:3389 , http://hdl.handle.net/10962/d1014554
Description: [From Introductory discussion]. The modern approach to any sociological problem is characterised by the attempt to analyse the contributory factors in such a way that their inter-active association is clearly discernible. The simple concept of "single cause and effect" is now recognised to be a traversity of social fact. Social Pathology, therefore, may be said to attempt to isolate the multiple factors involved in a given situation, and to endeavour to determine thelr mode of inter-action in order that remedial techniques may be applied effectively. Slum conditions are obviously pathologic, by which it is understood that the environment imposes strains upon the individual to which there is ineffective adjustment. The rehabilitation of such a population would involve the converse process, restoring individuals to a condition where they are able to cope in every respect with the demands of life at their respective class levels. It is very rare indeed that only a single factor is involved in a social pathological condition and for this reason it is quite possible that one- sided efforts at rehabilitation - such as the attempt to re-house ALL slum dwellers in sub-economic houses - have a tendency to increase the pathology in another direction. Rehabilitation must therefore be based on multi-factorial analysis in which allowance is, as far as possible, made for the inter-connection of each of the individual deviations from the normal. The aim of this thesis is to evaluate the effect of good housing conditions on the 2335 Coloured slum families re-housed in sub-economic houses at Schauder Township, Port Elizabeth, from the time that these houses were first available for occupancy.
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Date Issued: 1954

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A critical study of the evidence of Andries Stockenstrom before the Aborigines Committee in 1835, viewed in the light of his statements and policies before 1935

- Urie, J M

Authors: Urie, J M
Date: 1953
Subjects: Stockenstrom, Andries, 1792-1864 , Eastern Cape (South Africa) -- History -- 19th century
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2617 , http://hdl.handle.net/10962/d1013416
Description: In recent years, increasing interest has been taken in the career of Andries Stockenstrom. Detailed study of his policy as Landdrost of Graaff-Reinet , as Commissioner-General of the Eastern Districts, and as Lieutenant-Governor, has brought about a realization of the soundness and value of much of his work. This appreciation of the sterling qualities of Stockenstrom's character- despite his undoubtedly difficult temperament - has led to the tacit assumption that the accusations which were levelled against him, and the odium in which he was held in Albany, after his evidence before the Aborigines Committee 1835 -1836, were largely the result of unfortunate newspaper propaganda. That evidence, it is implied - coming as it did at a time when public opinion was peculiarly sensitive to criticism - was in fact, not as black as it had been painted. Yet the events of the period between the Commissioner-Generalship and the Lieutenant- Governorship have not only coloured the judgment upon Stockenstrom of almost every writer on South African history, but so influenced contemporary public opinion as to materially impair the efficiency of his Lieutenant-Governorship. In writing this thesis, it has heen my purpose to make a detailed study of such material as is available for the period 1833-1836, and to endeavour, by an analysis of the evidence more particularly in the light of the years before 1833, to set this significant period in Stockenstrom' s career in its right perspective.
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Date Issued: 1953

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A preliminary investigation of the ecology of the Larger Kleinmond River Estuary, Bathurst District

- Brown, Alexander Claude, 1931-2005

Authors: Brown, Alexander Claude, 1931-2005
Date: 1953
Subjects: Kleinemonde River Estuary (South Africa) , Estuaries -- South Africa , Estuarine ecology -- South Africa
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5904 , http://hdl.handle.net/10962/d1014611
Description: Introduction. On the coast of the Bathurst Division, Eastern Cape Province, some 42 miles south- east of Grahamstown, lie two estuaries opening within a few yards of one another. These are known as the Kleinemonde. This paper embodies the results of an ecological survey of the fauna of the Larger Kleinmond Estuary. The chief concern has been the aquatic fauna but animals living along the banks have also been dealt with as far as possible, as have the birds. This is the second of South Africa's blind estuaries to be studied, the Klein River, Hermanus, having been investigated in 1947-49 by workers from the University of Cape Town. Though common in South Africa, blind estuaries are rare in parts of the world such as Europe, and present an almost entirely new field of research for the ecologist. It is hoped, therefore, that the investigation of the Kleinmond Estuary and a comparison with the results obtained from the Klein River, Hermanus, will add to our knowledge of this subject and be of service to future investigators. The history of the Kleimnond River is worthy of mention, for the lagoon was not always blind and shallow. The early maps of the 1820 settlers show the river as a navigable stream; sailing vessels anchored out at sea and sent lighters up what was then known as the Lydendoch River to collect fresh meat. The area at the mouth of the river was called Port Jessie. In these early days the region abounded with game. Hippo and elephant were common. the former inhabiting deep pools in the upper reaches of the river; pools which have since completely silted up. Constant ploughing of the slopes adjoining the river has caused vast amounts of soil to be washed by rains into the stream, and today what was within living memory a deep, clear stream is a shallow, blind and muddy river, a reflection of man's destructive methods of farming. These changes must have had a far-reaching effect on the fauna of the estuary; an effect about which we can, alas, only speculate. It is perhaps significant that though rich in numbers, the fauna is poor in species, tunicates and echinoderms being apparently entirely absent. The work involved in this survey was undertaken between September 1952 and November 1953, under the direction of Professor J . Omer-Cooper of Rhodes University, frequent and regular visits being made to the estuary. The entire month of February, 1953, was spent on the shore of the lagoon, so that animals could be observed over a continuous period. The starting date of the survey was particularly fortunate, as on September 28th, 1952, the river came down in flood and broke through the sand-bar separating the lagoon from the sea. The work thus began at a definite point in the estuarine cycle, the importance of which it is hoped to show.
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Date Issued: 1953

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Die evolusie van nedersetting in die Sondagsriviervallei

- Potgieter, J M

Authors: Potgieter, J M
Date: 1953
Subjects: Land settlement -- South Africa -- Sundays River Valley , Agriculture -- South Africa -- Sundays River Valley , Irrigation -- South Africa -- Eastern Cape -- Sundays River Valley
Language: Afrikaans
Type: Thesis , Doctoral , PhD
Identifier: vital:4875 , http://hdl.handle.net/10962/d1013041
Description: Soos die titel aandui is hierdie verhandeling 'n volledige en noukeurige oorsig van die evolusie (ontwikkeling) van blanke nedersetting in die Sondagsriviervallei. Dis die eerste poging wat aangewend is om die ontwikkeling op alle gebiede van die grondlegging af tot op die huidige datum teen 'n geskiedkundige agtergrond te skilder. Maar dwarsdaur is daar getrag om 'n duidelike begrip van die interaksie van natuur en mens te handhaaf.
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Date Issued: 1953

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Studies in chromium complexes

- Friend, Maurice Temple

Authors: Friend, Maurice Temple
Date: 1953
Subjects: Complex ions , Chromium
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4474 , http://hdl.handle.net/10962/d1011892 , Complex ions , Chromium
Description: In this work physical and analytical methods have been used to investigate the potassium salts of certain dioxalato chromium (III) complexes. The solid potassium salts of the trioxalatochromiate and the cis and trans dioxalatodiaquochromiates together with a salt corresponding to potassium dioxalatosulphatoaquochromiate were prepared. The mono- and dihydroxo derivatives of the cis and trans dioxalatochromiates were also obtained in aqueous solution. The methods of preparation and analysis used are described. Spectrophotometric absorption curves obtained on solutions of these salts using a Beckman Spectrophotometer are in agreement with results of previous workers, and the new absorption curve obtained from a solution of the solid cis dioxalatodiaquochromia salt shows that it is pure and gives additional proof of the completeness of the trans - cis isomerisation. Summary, p. i.
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Date Issued: 1953

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Studies in chromium complexes

- Cooper, Desmond Rudolph

Authors: Cooper, Desmond Rudolph
Date: 1953
Subjects: Chromium , Complex ions
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4523 , http://hdl.handle.net/10962/d1014707
Description: The chemistry of co-ordination compounds in general has played an important role in the development of the modern theory of valency, but the properties of complex salts between chromium and organic compounds containing carboxyl and amino- groups are of additional interest because of their bearing on the theory of certain technological processes such as chromium plating and, in particular, chrome-tanning. Owing to the rapid development of valence theory over the last two decades the technological chemist finds himself at a disadvantage vis-a-vis his academic counterpart in attempting to interpret the results of researches relating to these compounds as he must rely on the less powerful "classical" approach to his problems. Hence the need was felt for a brief survey of modern concepts of valency in terms of wave mechanics. For a more extended study the reader may consult the appropriate references and text books.
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Date Issued: 1953

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Studies on Paragus (Diptera, Syrphidae)

- Stuckenberg, B R

Authors: Stuckenberg, B R
Date: 1953
Subjects: Syrphidae , Diptera
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5887 , http://hdl.handle.net/10962/d1013321
Description: As several new species are described in this thesis its full value can only be realised by its publication, and it has therefore been prepared with that end in view. The subject matter is divided into two parts, each of which has been treated quite independently of the other. Both parts are presented here in the form in which they have been offered for publication. The first paper consists of a systematic study of a complex of species within the genus Paragus. It includes descriptions of four new species, a new subspecies, an allotype, and redescriptions of two incompletely defined species. This paper has been offered for publication in the Transactions of the Royal Entomological Society of London. The second part consists of a study of all the Ethiopian species of Paragus except those covered by the first paper. It includes the definition of a new subgenus, and descriptions of two new species and three allotypes. It has been sent for publication in the "Revue Zoologie et Botanique de Africaine" at the invitation of Dr. P. Basilewsky of the Musee du Congo Belge, Tervuren.
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Date Issued: 1953

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The chemistry of the wattle tannins

- Roux, David Gerhardus

Authors: Roux, David Gerhardus
Date: 1953
Subjects: Tannin plants , Tannins , Wattles (Plants)
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: vital:4492 , http://hdl.handle.net/10962/d1013098
Description: Four species of acacia of Auatralian origin are associated with the wattle industry in South Africa. Black wattle, Acacia mollissima willd., is the most important of these and is today almost exclusively cultivated. The tree grows successfully only in a limited area of rich soil and high rainfall and is easily affected by adverse conditions caused by insect pests, frost damage and drought. Expansion of the area under cultivation is therefore, not feasible, although the world demand for vegetable extracts far exceeds the available supply. The remaining species such as green (Acacia decurrrens willd.) and silver wattles (Acacia dealbata Link.) possess many desirable characteristics which resist such adverse factors. Their barks, however, give reddish extracts, which are considered unsuitable for tannery usage because of the red colour they impart to the leather. Hybridisation studies, involving the crossing of green and silver wattle with the black, and aimed at produc1ng progenies containing many of the desirable characterlstics of the parent plants, are thus a natural result and have been in progress for a considerable period. Summary, p. i.
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Date Issued: 1953

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The petrology of the Khale dolerite sheet

- Eales, Hugh V

Authors: Eales, Hugh V
Date: 1953
Subjects: Petrology -- Botswana , Diabase -- Botswana
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5076 , http://hdl.handle.net/10962/d1014853
Description: In the hills and in the plain of the Khale area are exposed two sheets of quartz-dolerite, the upper sheet being locally mushroom-shaped. The rock corresponds loosely with the Downes mountain type of dolorite, and contains numerous horizons of coarse-grained dolorite-pegmatite. The plagioclase felspars are described with special reference to the variation of grain-size, the features of zoned crystals, and the possible causes of a peculiar brown clouding in the basic zones of the crystals. Phenocrysts of augite and pigeonite, as well as plagioclase are recorded in the chilled contact rock. The micrometric data indicate that the mineral composition of the specimens is largely governed by the oxidation state of the iron, and that the Soret effect has caused the marginal rock to be enriched in basic elements. Hydrothermal veinlets composed largely of chlorite occur in both the dolorite and the country rock, and evidence suggests that veins of both residual material and mobilised granite occur in the upper finer-grained dolorite.
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Date Issued: 1953

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The response of pure organic crystals to ionising radiations

- King, J W

Authors: King, J W
Date: 1953
Subjects: Inorganic scintillators , Crystals
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5529 , http://hdl.handle.net/10962/d1012641 , Inorganic scintillators , Crystals
Description: The introduction contains introductory remarks on scintillation counters together with a brief description of the exciton theory believed to be the means of primary energy migration within organic crystals. Part I contains a review of the data published on the reletive responses of different organic crystals and the attempted correlations of these results with the molecular structures of the different phosphors. From data which may be accepted as being both reliable and suitable for comparison it is concluded that theories involving correlations between phosphor efficiencies and molecular structures may be tested only if the efficiency data has (i) been extrapolated to give results for crystals of very small thickness and {ii) been obtained at very low temperatures. Part II contains accurate calculations based on the exciton theory proposed by Birks (1951 ) to account for the response of crystals to different types of ionising radiations. Satisfactory agreement is obta1ned with all the avalable experimental data in the literature. In part III an account is given of the response of organic crystals observed by the author for low-energy ⋉particles, and of the similar behaviour found by Taylor et al, (1951 ) for low-energy electrons. A possible extension of the theory described in part II, allowing for the escape of excitons through the crystal surface is given accounting for this behaviour. An exciton mean free path in anthracene, terphenyl and stilbene of about 3 - 7/u is obtained. Results were obtained with strong ⋉-particle sources which could not be explained. in terms ot normal response of the phosphor used. This effect was inventigatea as described in part IV, and it is shown that photons are produced in air, glass and quartz when these materials are irradiated by ⋉particles. This luminescence was probably responsible for the "scintillations" which Richards and Cole (1951) have ascribed to thin films of various materials. Problems requiring further investigation are indicated.
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Date Issued: 1953

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A preliminary investigation of the structure of green wattle tannin (acacia decurrens willd)

- Glueck, Leonard David

Authors: Glueck, Leonard David
Date: 1952
Subjects: Tannins , Tannin plants
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4475 , http://hdl.handle.net/10962/d1011988 , Tannins , Tannin plants
Description: Green wattle tannin extracts were separated by lead salt precipitation into a phenolic tannin fraction and a nontannin fraction. The combustion analysis of the tannin fraction corresponded to an empirical formula C₁₅H₁₄O₆. Methoxy and acetyl values showed four oxygens were hydroxy groups while the residual oxygens could either be ether linked or carbonyl groups. Diazomethane methylation produced a white product of high methoxyl value which indicated that the four hydroxyl groups were phenolic. Chromatography of the lead salt purified tannin showed an indistinct non-fluorescent trail. Ether extraction of the tannin removed the associated Phenolic bodies. The ethereal extract unlike black wattle extracts contained no fisetin and evaporation of the ethereal solutions yielded a gummy non-crystalline residue. Alkaline fusion of the purified tannin produced for the first tlme a variety of acidic and phenolic compounds i.e. resorcinol, pyrogaloll, phloroglucinol β-resorcylic acid, gallic acid and protocatechuic acid. From the high yields of resorcinol (6%) and gallic acid (3%), these units appear to predominate. These degradation productions, coupled with the analytical figures, indicate a possible C₁₅ unit with resorcinol and pyrogallol nuclei as a basis. The non-tannin fraction failed to reveal any compound which might cause the excessive redness in green wattle extracts. Chromatography of this non-tannin fraction showed the presence of sucrose.
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Date Issued: 1952

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A study of cation exchange in South African soils

- Du Toit, A A

Authors: Du Toit, A A
Date: 1952
Subjects: Soil chemistry , Ion exchange
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4462 , http://hdl.handle.net/10962/d1011506 , Soil chemistry , Ion exchange
Description: The colloidal fraction is the vital part of a soil. These extremely minute particles determine the nature of the soil and are mainly responsible for its many and varied functions. The most important of these functions is perhaps the ability of the colloids to adsorb and exchange cations, the elements so essential to all organisms as building materials. When pure water is passed through a non-saline. soil, the leachate will contain very few dissolved cations. If, on the other hand, an electrolyte such as a weak solution of sodiun chloride, is passed through the same soil, the leachate will contain considerable quantities of calcium, magnesium and potassiun chlorides as well as much of the original sodium chloride. The number of equivalents of the cations collected will be approximately the same as the number of equivalents of sodium ions added. Sodium ions have displaced some of the calcian, magnesium and potassium ions from the soil. This phenomenon is known as cation exchange. Intro., p. 1.
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Date Issued: 1952

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An historical survey of the Bethelsdorp station of the London Missionary Society, from its inception, and until the death of Doctor van der Kemp, in 1811

- Briggs, D Roy

Authors: Briggs, D Roy
Date: 1952
Subjects: London Missionary Society -- History , Bethelsdorp (South Africa) -- History
Language: English
Type: Thesis , Bachelor , BDiv
Identifier: vital:1290 , http://hdl.handle.net/10962/d1014609
Description: In South Africa the small town or hamlet, nestling - as is so often the case - at the foot of a mountain, frequently proclaims its identity to the traveller by inscribing its name in great, white-washed letters of stone upon the side of the hill. If this were the case with Bethelsdorp, the temptation would be to write on those bare, rocky hills, that form the back-drop for the drama a century and a half have seen on its stage, the one word, "Ichabod." For the glory has departed. And some would even question whether any of its days had been glorious. Around this small outpost of Christendom have centred, from its earliest beginnings, both praise and contumely. It is the purpose of this investigation to attempt to judge between these opinions, in an attempt to arrive at the truth, by a survey of the years Bethelsdorp enjoyed under the direction of Johannes Theodorus van der Kemp. He has had many critics, many protagonists: perhaps of no other man in the short history of this land has there been such diversity of opinion. Before the judgments of historians and biographers can be assessed, however, the facts of his work must be appreciated, and the effort towards understanding must be preceded by a brief description of the circumstances antecedent to the foundation of that station, which marked the summt of his life and work.
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Date Issued: 1952

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