"The great foes of reality" : attitudes to language in selected novels by Joseph Conrad
- Authors: McDonald, Peter
- Date: 2013-02-19
- Subjects: Conrad, Joseph, 1857-1924
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2183 , http://hdl.handle.net/10962/d1001836 , Conrad, Joseph, 1857-1924
- Description: This dissertation examines Conrad's ambivalent attitude to the value of words in human affairs. Though his critical attitude is the main focus of the argument, his positive attitude will also be considered in some detail. In the first chapter, on The Nigger of the 'Narcissus', the critical attitude is primary. In this story language is seen in relation to silence and action, and in both cases the non- linguistic element is celebrated, while words are censured. Yet the values implied by the tale leave the writer of fiction, and the narrator who emerges at the end of the story, in an uncertain position: the world presented in the novel undermines the mode of presentation which is the novel. This paradox is to some extent resolved in the following two chapters which deal with Conrad's complex response to the culture of European imperialism. Chapter 2, on Heart of Darkness, examines the ways in which words contribute to the systematic lies that sustain the nineteenth-century civilizing mission. The story is, however, not wholly critical of language, since the value of Marlow's spoken narrative is clearly endorsed. Chapter 3 offers a more detailed account of the relationship between the story-teller and his society, and of the value of Marlow's words. In Lord Jim, Marlow's account of Jim is contrasted with the account of him given by the court of inquiry, and with the notion of the hero projected in the romantic fictions which Jim reads. Once again Marlow's use of language is affirmed, while other uses are shown to be reductive, or simply spurious. The final chapter deals with Under Western Eyes. Of the four novels selected for this thesis, Conrad's "Russian novel" offers the most explicit and sustained critique of language. The novel suggests that any simplistic identification of language with "communication" is naive, if not misleading. In the conclusion I discuss Conrad's understanding of the nature and function of his own words, as set out in the preface to The Nigger of the 'Narcissus' and A Personal Record
- Full Text:
- Authors: McDonald, Peter
- Date: 2013-02-19
- Subjects: Conrad, Joseph, 1857-1924
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2183 , http://hdl.handle.net/10962/d1001836 , Conrad, Joseph, 1857-1924
- Description: This dissertation examines Conrad's ambivalent attitude to the value of words in human affairs. Though his critical attitude is the main focus of the argument, his positive attitude will also be considered in some detail. In the first chapter, on The Nigger of the 'Narcissus', the critical attitude is primary. In this story language is seen in relation to silence and action, and in both cases the non- linguistic element is celebrated, while words are censured. Yet the values implied by the tale leave the writer of fiction, and the narrator who emerges at the end of the story, in an uncertain position: the world presented in the novel undermines the mode of presentation which is the novel. This paradox is to some extent resolved in the following two chapters which deal with Conrad's complex response to the culture of European imperialism. Chapter 2, on Heart of Darkness, examines the ways in which words contribute to the systematic lies that sustain the nineteenth-century civilizing mission. The story is, however, not wholly critical of language, since the value of Marlow's spoken narrative is clearly endorsed. Chapter 3 offers a more detailed account of the relationship between the story-teller and his society, and of the value of Marlow's words. In Lord Jim, Marlow's account of Jim is contrasted with the account of him given by the court of inquiry, and with the notion of the hero projected in the romantic fictions which Jim reads. Once again Marlow's use of language is affirmed, while other uses are shown to be reductive, or simply spurious. The final chapter deals with Under Western Eyes. Of the four novels selected for this thesis, Conrad's "Russian novel" offers the most explicit and sustained critique of language. The novel suggests that any simplistic identification of language with "communication" is naive, if not misleading. In the conclusion I discuss Conrad's understanding of the nature and function of his own words, as set out in the preface to The Nigger of the 'Narcissus' and A Personal Record
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Perspectives on isolation: the relation of narrative technique to theme in selected works by Joseph Conrad
- Authors: Gaylard, Robin Peter
- Date: 2013-02-13
- Subjects: Conrad, Joseph, 1857-1924
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2182 , http://hdl.handle.net/10962/d1001833 , Conrad, Joseph, 1857-1924
- Description: " ... the central concern of this thesis, which is to investigate the ways in which Conrad uses a particular technique (that of the first-person narrator ) to focus our attention, to secure our involvement, and to direct our sympathies. At the same time I wish to examine the extent to which the central themes or concerns of each work derive from the interaction between the narrator and the man whose experience he confronts, from "the challenging interplay of two frames of reference, two schemes of values, two sets of attitudes" that the use of a dramatized narrator makes possible." (Introd., p. 5) , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Authors: Gaylard, Robin Peter
- Date: 2013-02-13
- Subjects: Conrad, Joseph, 1857-1924
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2182 , http://hdl.handle.net/10962/d1001833 , Conrad, Joseph, 1857-1924
- Description: " ... the central concern of this thesis, which is to investigate the ways in which Conrad uses a particular technique (that of the first-person narrator ) to focus our attention, to secure our involvement, and to direct our sympathies. At the same time I wish to examine the extent to which the central themes or concerns of each work derive from the interaction between the narrator and the man whose experience he confronts, from "the challenging interplay of two frames of reference, two schemes of values, two sets of attitudes" that the use of a dramatized narrator makes possible." (Introd., p. 5) , Adobe Acrobat 9.53 Paper Capture Plug-in
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Gold exploration northeast of Ngundu Halt, northern marginal zone of the Limpopo Belt, Zimbabwe
- Authors: Simango, Robert Zulu
- Date: 2004 , 2013-05-30
- Subjects: Geology -- Zimbabwe , Gold ores -- Geology -- Zimbabwe , Greenstone belts -- Zimbabwe , Gold mines and mining -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5007 , http://hdl.handle.net/10962/d1005844 , Geology -- Zimbabwe , Gold ores -- Geology -- Zimbabwe , Greenstone belts -- Zimbabwe , Gold mines and mining -- Zimbabwe
- Description: Gold exploration was conducted in northern margin, granulite-facies rocks of the Limpopo Belt. Methods used in the prospecting include drainage, soil and rock geochemistry, geophysical surveys, geological mapping, trenching and diamond drilling. These techniques successfully led to the discovery of two medium size, mesothermal gold deposits (Grid 2s and Grid 4). Objectives of this study were to (a) document the exploration methodology used; (b) describe the regional geology; (c) establish a mineral deposit model; (d) outline the methods and results of various exploration techniques; (e) outline follow-up procedures and evaluation of anomalies; and (f) discuss results of the exploration exercise and conclusions. The granulite-facies terrain comprises Charno-enderbites, mafic and felsic to intermediate metavolcanic rocks and meta-sediments. Renco Mine situated immediately east of the study area, was selected as the ore deposit model for the exploration program. Gold mineralization occurs in shear and thrust zones within an enderbite. The gold deposits are structurally controlled by a first-order, Sinistral transcrustal Mauch Shear Zone, which is parallel to a regional east-northeast penetrative foliation. The deposits are in dilation zones where the Mauch Shear (a) is intersected by a dextral east-west shear (Grid 2s), or (b) has a sinistral splay (Grid 4 and Renco). Close to these deposits, the Mauch Shear is in contact with a "greenstone belt", which is a possible source of crustal metamorphic ore fluids and gold. The Grid 2s deposit contains fine-grained, disseminated free gold, and small amounts of pyrrhotite, pyrite and chalcopyrite in quartz veins within third-order shears in K-feldspar granite. K-feldspar, sericitic, silicic, sulphidation and carbonate alteration characterizes the deposit, which has a proposed mantle-degassing model. The Grid 4 deposit is magmatic porphyry-type, with CuMo and Au in third- and fourth-order shears respectively. Mineralization comprises disseminated to semi-massive pyrrhotite, pyrite, chalcopyrite, sphalerite, bismuth, molybdenite and gold. Wall rock alteration includes biotitic, chloritic, silicic, sulphidation and carbonate. In Grid 2s, Grid 4 and Renco deposits, the alteration mineral assemblages are in three facies, which are granulite, amphibolte and greenschist. In the three deposits, the mineralization occurs with the amphibolite-facies, indicating post-peak, retrograde metamorphic conditions. , Illustrations (maps) only available in print form at Cory Library , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2004
- Authors: Simango, Robert Zulu
- Date: 2004 , 2013-05-30
- Subjects: Geology -- Zimbabwe , Gold ores -- Geology -- Zimbabwe , Greenstone belts -- Zimbabwe , Gold mines and mining -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5007 , http://hdl.handle.net/10962/d1005844 , Geology -- Zimbabwe , Gold ores -- Geology -- Zimbabwe , Greenstone belts -- Zimbabwe , Gold mines and mining -- Zimbabwe
- Description: Gold exploration was conducted in northern margin, granulite-facies rocks of the Limpopo Belt. Methods used in the prospecting include drainage, soil and rock geochemistry, geophysical surveys, geological mapping, trenching and diamond drilling. These techniques successfully led to the discovery of two medium size, mesothermal gold deposits (Grid 2s and Grid 4). Objectives of this study were to (a) document the exploration methodology used; (b) describe the regional geology; (c) establish a mineral deposit model; (d) outline the methods and results of various exploration techniques; (e) outline follow-up procedures and evaluation of anomalies; and (f) discuss results of the exploration exercise and conclusions. The granulite-facies terrain comprises Charno-enderbites, mafic and felsic to intermediate metavolcanic rocks and meta-sediments. Renco Mine situated immediately east of the study area, was selected as the ore deposit model for the exploration program. Gold mineralization occurs in shear and thrust zones within an enderbite. The gold deposits are structurally controlled by a first-order, Sinistral transcrustal Mauch Shear Zone, which is parallel to a regional east-northeast penetrative foliation. The deposits are in dilation zones where the Mauch Shear (a) is intersected by a dextral east-west shear (Grid 2s), or (b) has a sinistral splay (Grid 4 and Renco). Close to these deposits, the Mauch Shear is in contact with a "greenstone belt", which is a possible source of crustal metamorphic ore fluids and gold. The Grid 2s deposit contains fine-grained, disseminated free gold, and small amounts of pyrrhotite, pyrite and chalcopyrite in quartz veins within third-order shears in K-feldspar granite. K-feldspar, sericitic, silicic, sulphidation and carbonate alteration characterizes the deposit, which has a proposed mantle-degassing model. The Grid 4 deposit is magmatic porphyry-type, with CuMo and Au in third- and fourth-order shears respectively. Mineralization comprises disseminated to semi-massive pyrrhotite, pyrite, chalcopyrite, sphalerite, bismuth, molybdenite and gold. Wall rock alteration includes biotitic, chloritic, silicic, sulphidation and carbonate. In Grid 2s, Grid 4 and Renco deposits, the alteration mineral assemblages are in three facies, which are granulite, amphibolte and greenschist. In the three deposits, the mineralization occurs with the amphibolite-facies, indicating post-peak, retrograde metamorphic conditions. , Illustrations (maps) only available in print form at Cory Library , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2004
Microemulsions : a new perspective in the treatment of paediatric and geriatric tuberculosis patients
- Authors: Wisch, Michael Henry
- Date: 2000
- Subjects: Emulsions (Pharmacy) , Tuberculosis -- Treatment -- South Africa , Tuberculosis in children -- Treatment , Tuberculosis in old age -- Treatment , Tuberculosis -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3805 , http://hdl.handle.net/10962/d1003283 , Emulsions (Pharmacy) , Tuberculosis -- Treatment -- South Africa , Tuberculosis in children -- Treatment , Tuberculosis in old age -- Treatment , Tuberculosis -- Treatment
- Description: Tuberculosis(TB) was declared to be a global emergency in 1993, with South Africa declaring it to be the country’s top health priority in 1996, but ineffective treatment strategies have led to fewer than half of all treated patients in South Africa being cured. At present,paediatric treatment remains a problem, as the antitubercular preparations of rifampicin, isoniazid and pyrazinamide, that are currently available, were not initially designed for the treatment of paediatric TB patients, providing a motivation for this project. The aim of this project is thus the development of a microemulsion dosage form for the oral delivery of RIF(Rifampicin), INH(Isoniazid) and PZA(Pyrazinamide) in combination. RIF, INH and PZA were adequately characterised with reference to the monograph standards referenced and were found to be sufficiently pure to be used in subsequent work. A chromatographic system and conditions were selected and validated as being optimal for HPLC analysis of RIF, INH and PZA in combination, with a drug partitioning method for miglyol 812 developed and validated. Ternary and pseudo-ternary phase diagrams were constructed and reported, all employing miglyol 812 as the lipid. It was undoubtedly the imwitor 308 and crillet 3 combination o/w microemulsion system that proved most successful, maintaining homogeneity on dilution. The microemulsion used in formulation comprised imwitor 308 (27.63%), crillet 3 (27.63%), miglyol 812 23.68%) and water (21.06%). The stability of RIF, INH and PZA was investigated in aqueous solution, miglyol 812, corn oil, 10%m/v cremophor RH, 5%m/v imwitor 308, 10%m/v crillet 3 and 70%m/v sorbitol solution. Trends in the stability assessments conducted on RIF, INH and PZA were noted, with slight variation depending on the formulation component being evaluated. RIF invariably demonstrated temperature and oxidation dependent degradation in all vehicles, with a definite distinction possible between samples stored at 25, 40 and 600C over a 7 day trial period. A definite advantage of storing RIF solutions under nitrogen was observed, with these solutions showing less degradation over the course of the trial, than those stored under air. INH produced a pronounced increase in the degree of degradation of RIF, whereas PZA had a negligible effect on it’s stability. INH proved to be most stable in the 70%m/v sorbitol solution with no significant oxidation or temperature dependent degradation indicated. Temperature dependent degradation was only noticable when INH was in combination with RIF, most significant in crillet 3 solution. PZA was the most stable of the three drugs, remaining relatively unaffected by temperature and the presence of air, independent of the vehicle employed, although the drug remaining did decrease slightly in the presence of RIF.Due to drug dose specifications and solubility limitations, the final formulation assessed, only contained RIF and INH, despite INH and PZA having no significant effect on the stability of each other. The solubility of PZA in the lipid and aqueous components of the microemulsion was not great enough to achieve the required 500 mg/10ml dose, while RIF and INH could achieve the respective 150mg/10ml and 100mg/10ml dose. RIF stability was improved, as anticipated, with the incorporation of RIF into the internal phase decreasing contact with INH which has been shown to affect it’s stability. RIF behaved as predicted, possessing greater stability than shown in the individual formulation components, however, INH did not, being less stable in formulation in the absence of antioxidant, than in it’s presence. A novel microemulsion formulation capable of delivering the incompatible RIF and INH in combination, with numerous microemulsion systems mapped,with the ability of being used for the delivery of other lipophilic drugs and drug combinations, was produced.The final formulation provided valuable information into possible future improvements of the microemulsion to improve drug stability.
- Full Text:
- Date Issued: 2000
- Authors: Wisch, Michael Henry
- Date: 2000
- Subjects: Emulsions (Pharmacy) , Tuberculosis -- Treatment -- South Africa , Tuberculosis in children -- Treatment , Tuberculosis in old age -- Treatment , Tuberculosis -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3805 , http://hdl.handle.net/10962/d1003283 , Emulsions (Pharmacy) , Tuberculosis -- Treatment -- South Africa , Tuberculosis in children -- Treatment , Tuberculosis in old age -- Treatment , Tuberculosis -- Treatment
- Description: Tuberculosis(TB) was declared to be a global emergency in 1993, with South Africa declaring it to be the country’s top health priority in 1996, but ineffective treatment strategies have led to fewer than half of all treated patients in South Africa being cured. At present,paediatric treatment remains a problem, as the antitubercular preparations of rifampicin, isoniazid and pyrazinamide, that are currently available, were not initially designed for the treatment of paediatric TB patients, providing a motivation for this project. The aim of this project is thus the development of a microemulsion dosage form for the oral delivery of RIF(Rifampicin), INH(Isoniazid) and PZA(Pyrazinamide) in combination. RIF, INH and PZA were adequately characterised with reference to the monograph standards referenced and were found to be sufficiently pure to be used in subsequent work. A chromatographic system and conditions were selected and validated as being optimal for HPLC analysis of RIF, INH and PZA in combination, with a drug partitioning method for miglyol 812 developed and validated. Ternary and pseudo-ternary phase diagrams were constructed and reported, all employing miglyol 812 as the lipid. It was undoubtedly the imwitor 308 and crillet 3 combination o/w microemulsion system that proved most successful, maintaining homogeneity on dilution. The microemulsion used in formulation comprised imwitor 308 (27.63%), crillet 3 (27.63%), miglyol 812 23.68%) and water (21.06%). The stability of RIF, INH and PZA was investigated in aqueous solution, miglyol 812, corn oil, 10%m/v cremophor RH, 5%m/v imwitor 308, 10%m/v crillet 3 and 70%m/v sorbitol solution. Trends in the stability assessments conducted on RIF, INH and PZA were noted, with slight variation depending on the formulation component being evaluated. RIF invariably demonstrated temperature and oxidation dependent degradation in all vehicles, with a definite distinction possible between samples stored at 25, 40 and 600C over a 7 day trial period. A definite advantage of storing RIF solutions under nitrogen was observed, with these solutions showing less degradation over the course of the trial, than those stored under air. INH produced a pronounced increase in the degree of degradation of RIF, whereas PZA had a negligible effect on it’s stability. INH proved to be most stable in the 70%m/v sorbitol solution with no significant oxidation or temperature dependent degradation indicated. Temperature dependent degradation was only noticable when INH was in combination with RIF, most significant in crillet 3 solution. PZA was the most stable of the three drugs, remaining relatively unaffected by temperature and the presence of air, independent of the vehicle employed, although the drug remaining did decrease slightly in the presence of RIF.Due to drug dose specifications and solubility limitations, the final formulation assessed, only contained RIF and INH, despite INH and PZA having no significant effect on the stability of each other. The solubility of PZA in the lipid and aqueous components of the microemulsion was not great enough to achieve the required 500 mg/10ml dose, while RIF and INH could achieve the respective 150mg/10ml and 100mg/10ml dose. RIF stability was improved, as anticipated, with the incorporation of RIF into the internal phase decreasing contact with INH which has been shown to affect it’s stability. RIF behaved as predicted, possessing greater stability than shown in the individual formulation components, however, INH did not, being less stable in formulation in the absence of antioxidant, than in it’s presence. A novel microemulsion formulation capable of delivering the incompatible RIF and INH in combination, with numerous microemulsion systems mapped,with the ability of being used for the delivery of other lipophilic drugs and drug combinations, was produced.The final formulation provided valuable information into possible future improvements of the microemulsion to improve drug stability.
- Full Text:
- Date Issued: 2000
An examination of employee participation as provided for in the Labour Relations Act 66 of 1995
- Authors: Khoza, Francisco Jabulani
- Date: 1999
- Subjects: Decision making , Management -- Employee participation , Labor laws and legislation -- South Africa , South Africa. Labour Relations Act, 1995
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3676 , http://hdl.handle.net/10962/d1003191 , Decision making , Management -- Employee participation , Labor laws and legislation -- South Africa , South Africa. Labour Relations Act, 1995
- Description: The thesis covers the field of labour law known as employee participation in decision-making. It deals with the examination of the extent to which the Labour Relations Act 66 of 1995 (the Act) promotes employee participation in decision-making. Firstly, the analysis shows that employee participation in decision-making is an aspect of democracy, which is translated into industrial democracy in industrial relations. In South Africa the philosophical foundation of employee participation is supported by the Constitution of the Republic of South Africa Act 108 of 1996 which embodies democratic values permeating all areas of the law including labour law. Secondly, the study elucidates the jurisprudential background of employee participation in South Africa. There is evidence of the development of some principles of participation like consultation; information disclosure; and the existence of participatory forums like works councils under the LRA 28 of 1956. Thirdly, in evaluating the extent to which the LRA 66 of 1995 promotes employee participation, the following aspects are covered: the relevance and contribution of information disclosure; the effect of consultation prior to dismissal for operational requirements; the role of collective bargaining; and the contribution of workplace forums. The conclusion is reached that all the foregoing aspects of the LRA 66 of 1995 will contribute to the promotion of employee participation in decision-making. The Labour Court and the Commission for Conciliation Mediation and Arbitration can also ensure that in interpreting the Act employee participation is promoted where appropriate. Finally, employers and employees will have to accept this necessary partnership for the entrenchment of employee participation in decision-making.
- Full Text:
- Date Issued: 1999
- Authors: Khoza, Francisco Jabulani
- Date: 1999
- Subjects: Decision making , Management -- Employee participation , Labor laws and legislation -- South Africa , South Africa. Labour Relations Act, 1995
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3676 , http://hdl.handle.net/10962/d1003191 , Decision making , Management -- Employee participation , Labor laws and legislation -- South Africa , South Africa. Labour Relations Act, 1995
- Description: The thesis covers the field of labour law known as employee participation in decision-making. It deals with the examination of the extent to which the Labour Relations Act 66 of 1995 (the Act) promotes employee participation in decision-making. Firstly, the analysis shows that employee participation in decision-making is an aspect of democracy, which is translated into industrial democracy in industrial relations. In South Africa the philosophical foundation of employee participation is supported by the Constitution of the Republic of South Africa Act 108 of 1996 which embodies democratic values permeating all areas of the law including labour law. Secondly, the study elucidates the jurisprudential background of employee participation in South Africa. There is evidence of the development of some principles of participation like consultation; information disclosure; and the existence of participatory forums like works councils under the LRA 28 of 1956. Thirdly, in evaluating the extent to which the LRA 66 of 1995 promotes employee participation, the following aspects are covered: the relevance and contribution of information disclosure; the effect of consultation prior to dismissal for operational requirements; the role of collective bargaining; and the contribution of workplace forums. The conclusion is reached that all the foregoing aspects of the LRA 66 of 1995 will contribute to the promotion of employee participation in decision-making. The Labour Court and the Commission for Conciliation Mediation and Arbitration can also ensure that in interpreting the Act employee participation is promoted where appropriate. Finally, employers and employees will have to accept this necessary partnership for the entrenchment of employee participation in decision-making.
- Full Text:
- Date Issued: 1999
An investigation of the structural problems in relation to some synthetic waxes
- Authors: Stokhuyzen, Rolf
- Date: 1970
- Subjects: Chemistry, Analytic , Waxes , Synthetic products
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4443 , http://hdl.handle.net/10962/d1007695 , Chemistry, Analytic , Waxes , Synthetic products
- Description: From Introduction: Wax and wax-like substances have been defined in many ways. One reasonably extensive definition, by Hatt and Lamberton (1956) is given below: "The term "wax" seems best used to denote a group of substances which qualitatively have certain physical properties in common. These properties are familiar ones, for in almost all countries some natural wax - beeswax, Japan wax, Chinese insect wax, the carnauba and candelilla waxes of the Americas - has been an important material in art and industry from prehistoric times. Waxes are understood to be opaque or translucent solids, which melt without decomposition to form mobile liquids at temperatures in the region of 100⁰C. They differ in hardness, but are all essentially soft substances with poor mechanical strength. Most waxes can be easily shaped or kneaded at a little above ambient temperatures. In fact, the term could easily have been made to cover the whole class now named thermoplastics." Pure n-paraffins would be too crystalline and brittle for use as waxes, whereas mixtures of n-paraffins have some valuable properties. The molecules bear such close resemblance to one another that they form mixed crystals of lowered crystallinity and the melting point is a function of the mean molecular weight. This is a desirable feature for it permits crystallinity and brittleness to be reduced without a marked loss in the melting point or hardness. It also allows a mixture to simulate a pure compound very closely. Waxes, in general, have been put to a large number of uses. They are used, for example, in candles, polishes, paper-coating, plastics, printing, matches, rust protectants and insulation. Each application requires its own appropriate range of wax properties.
- Full Text:
- Date Issued: 1970
- Authors: Stokhuyzen, Rolf
- Date: 1970
- Subjects: Chemistry, Analytic , Waxes , Synthetic products
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4443 , http://hdl.handle.net/10962/d1007695 , Chemistry, Analytic , Waxes , Synthetic products
- Description: From Introduction: Wax and wax-like substances have been defined in many ways. One reasonably extensive definition, by Hatt and Lamberton (1956) is given below: "The term "wax" seems best used to denote a group of substances which qualitatively have certain physical properties in common. These properties are familiar ones, for in almost all countries some natural wax - beeswax, Japan wax, Chinese insect wax, the carnauba and candelilla waxes of the Americas - has been an important material in art and industry from prehistoric times. Waxes are understood to be opaque or translucent solids, which melt without decomposition to form mobile liquids at temperatures in the region of 100⁰C. They differ in hardness, but are all essentially soft substances with poor mechanical strength. Most waxes can be easily shaped or kneaded at a little above ambient temperatures. In fact, the term could easily have been made to cover the whole class now named thermoplastics." Pure n-paraffins would be too crystalline and brittle for use as waxes, whereas mixtures of n-paraffins have some valuable properties. The molecules bear such close resemblance to one another that they form mixed crystals of lowered crystallinity and the melting point is a function of the mean molecular weight. This is a desirable feature for it permits crystallinity and brittleness to be reduced without a marked loss in the melting point or hardness. It also allows a mixture to simulate a pure compound very closely. Waxes, in general, have been put to a large number of uses. They are used, for example, in candles, polishes, paper-coating, plastics, printing, matches, rust protectants and insulation. Each application requires its own appropriate range of wax properties.
- Full Text:
- Date Issued: 1970
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