Rights-based restitution in South Africa : developmental land reform or relocation in reverse?
- Authors: Roodt, Monty
- Date: 2004
- Subjects: Restitution -- South Africa , Land reform -- South Africa , Right of property -- South Africa , Land settlement -- South Africa , Land tenure -- South Africa , South Africa -- Commission on Restitution of Land Rights
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3351 , http://hdl.handle.net/10962/d1007211 , Restitution -- South Africa , Land reform -- South Africa , Right of property -- South Africa , Land settlement -- South Africa , Land tenure -- South Africa , South Africa -- Commission on Restitution of Land Rights
- Description: The main question of this thesis is to what extent the rights-based and market-driven nature of the restitution program has given rise to a legalistic and bureaucratic process that negates both the demand-driven and the developmental aspects of restitution as land reform. I answer this question by showing that the choice of a Constitutional model with a Bill of Rights provides the background for a rights-based land reform program. This is especially true for the restitution sub-program, one of the three branches along with redistribution and tenure of the overall land reform program. I then consider the debate around the property clause, and how its inclusion provided the context for a market and rights-based approach to land reform as opposed to a supply-led administrative approach. Because the property clause as a First Generation right prevents expropriation of land without market-related compensation, a complex and legalistic land reform program falling within the ambit of Second Generation rights was formulated to address the gross imbalance in land ownership in South Africa. I argue that the contemporary origin of Second Generation human rights lies within the context of class and anti-globalisation struggles for democracy, and that they are something to be fought for and defended. I discuss the distinction between First, Second and Third Generation rights and identify four spheres within which the struggle for Second and Third Generation rights takes place within modern democratic states. These are the state, the representative public sphere, civil society and the private sphere. I then deal with the problem of trying to turn "paper rights" into realisable rights for the more disadvantaged sectors of society. I also look at what impedes their realisation. I argue that a number of strategies are necessary to ensure the delivery of Second and Third Generation rights. These are an adequate legislative framework, a good communication strategy, the development of institutional capacity to deliver, and if all else fails, access to conflict resolution mechanisms. I consider the major impediments to the realisation of Second and Third Generation rights to be the way in which they are defined in relation to First Generation rights, especially the property clause, the way in which access to rights-backed resources through formal institutions are mediated by the operation of informal institutions, and the dearth of administrative competence in South Africa. My point is that in order for Second and Third Generation rights to have practical benefit for the dispossessed and poor, extraordinary measures are needed. The Restitution arm of the land reform program provides in theory just such extraordinary measures, albeit for only a section of the population. I analyse the effectiveness of the Land Claims Court in assisting restitution claimants and the rural poor to realize their rights. I trace the slow and haphazard shift from a positivistic statutory interpretation (narrow, literal, legalistic) to a purposive interpretation (informed by the Constitutional spirit and social purpose of the legislation) by the Court. This is followed by an analysis of the restitution business process, which means tracing the path of the claim from lodgement to settlement. I set out the costly, complex and legalistic implementation and policy process in some detail. My argument is that in order for a rights-based approach to overcome the impediments outlined in Chapter 3, as well as the property clause in the Constitution, its architects designed a complex process that in the end proved counter-productive in terms of its original aims. The failure of the process to deliver led in 1998 the then Minister of Land Affairs, Derek Hannekom, to appoint a Ministerial Review to investigate the problems. Problems included: slowness of delivery, the crisis of unplannability, low levels of trust between implementers, and high levels of frustration. Two issues are analysed more fully, the rights-driven approach as opposed to the rights-based approach and the lack of claimant participation in taking control of the restitution process. I examine the relationship of the Restitution Commission to the Department of Land Affairs and to municipal land use planning processes. The emphasis on rights within the restitution program had the effect of distancing restitution, especially in the first few years of the programs' existence, from the rest of the land reform program, as well as from the local government process of formulating land development objectives (LDOs), and the Integrated Development Planning (lOP) process. I look at the Port Elizabeth Land and Community Restoration Association (Pelcra) as a case study as it embodies an approach that tries to move beyond a mere reclaiming of rights in land and attempts to implement a developmental approach. I conclude that the rights-based restitution program in spite of its many shortcomings has had some success. It has moved slowly from an overly legalistic judicial program to a more administrative but still bureaucratic process, that has delivered only 27 percent of its product as land reform, the rest going to monetary compensation mainly in urban areas. Thus it can be argued that restitution has been more successful as a program to promote reconciliation along the lines of the Truth and Reconciliation Commission, than as a land reform program, especially if one regards land reform as the restoration of rural land to the indigenous population. There have also been some successful attempts by the Commission, such as in the case of PELCRA, to integrate the processing of its claims with local government planning processes, but progress in this direction remains patchy.
- Full Text:
- Date Issued: 2004
- Authors: Roodt, Monty
- Date: 2004
- Subjects: Restitution -- South Africa , Land reform -- South Africa , Right of property -- South Africa , Land settlement -- South Africa , Land tenure -- South Africa , South Africa -- Commission on Restitution of Land Rights
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3351 , http://hdl.handle.net/10962/d1007211 , Restitution -- South Africa , Land reform -- South Africa , Right of property -- South Africa , Land settlement -- South Africa , Land tenure -- South Africa , South Africa -- Commission on Restitution of Land Rights
- Description: The main question of this thesis is to what extent the rights-based and market-driven nature of the restitution program has given rise to a legalistic and bureaucratic process that negates both the demand-driven and the developmental aspects of restitution as land reform. I answer this question by showing that the choice of a Constitutional model with a Bill of Rights provides the background for a rights-based land reform program. This is especially true for the restitution sub-program, one of the three branches along with redistribution and tenure of the overall land reform program. I then consider the debate around the property clause, and how its inclusion provided the context for a market and rights-based approach to land reform as opposed to a supply-led administrative approach. Because the property clause as a First Generation right prevents expropriation of land without market-related compensation, a complex and legalistic land reform program falling within the ambit of Second Generation rights was formulated to address the gross imbalance in land ownership in South Africa. I argue that the contemporary origin of Second Generation human rights lies within the context of class and anti-globalisation struggles for democracy, and that they are something to be fought for and defended. I discuss the distinction between First, Second and Third Generation rights and identify four spheres within which the struggle for Second and Third Generation rights takes place within modern democratic states. These are the state, the representative public sphere, civil society and the private sphere. I then deal with the problem of trying to turn "paper rights" into realisable rights for the more disadvantaged sectors of society. I also look at what impedes their realisation. I argue that a number of strategies are necessary to ensure the delivery of Second and Third Generation rights. These are an adequate legislative framework, a good communication strategy, the development of institutional capacity to deliver, and if all else fails, access to conflict resolution mechanisms. I consider the major impediments to the realisation of Second and Third Generation rights to be the way in which they are defined in relation to First Generation rights, especially the property clause, the way in which access to rights-backed resources through formal institutions are mediated by the operation of informal institutions, and the dearth of administrative competence in South Africa. My point is that in order for Second and Third Generation rights to have practical benefit for the dispossessed and poor, extraordinary measures are needed. The Restitution arm of the land reform program provides in theory just such extraordinary measures, albeit for only a section of the population. I analyse the effectiveness of the Land Claims Court in assisting restitution claimants and the rural poor to realize their rights. I trace the slow and haphazard shift from a positivistic statutory interpretation (narrow, literal, legalistic) to a purposive interpretation (informed by the Constitutional spirit and social purpose of the legislation) by the Court. This is followed by an analysis of the restitution business process, which means tracing the path of the claim from lodgement to settlement. I set out the costly, complex and legalistic implementation and policy process in some detail. My argument is that in order for a rights-based approach to overcome the impediments outlined in Chapter 3, as well as the property clause in the Constitution, its architects designed a complex process that in the end proved counter-productive in terms of its original aims. The failure of the process to deliver led in 1998 the then Minister of Land Affairs, Derek Hannekom, to appoint a Ministerial Review to investigate the problems. Problems included: slowness of delivery, the crisis of unplannability, low levels of trust between implementers, and high levels of frustration. Two issues are analysed more fully, the rights-driven approach as opposed to the rights-based approach and the lack of claimant participation in taking control of the restitution process. I examine the relationship of the Restitution Commission to the Department of Land Affairs and to municipal land use planning processes. The emphasis on rights within the restitution program had the effect of distancing restitution, especially in the first few years of the programs' existence, from the rest of the land reform program, as well as from the local government process of formulating land development objectives (LDOs), and the Integrated Development Planning (lOP) process. I look at the Port Elizabeth Land and Community Restoration Association (Pelcra) as a case study as it embodies an approach that tries to move beyond a mere reclaiming of rights in land and attempts to implement a developmental approach. I conclude that the rights-based restitution program in spite of its many shortcomings has had some success. It has moved slowly from an overly legalistic judicial program to a more administrative but still bureaucratic process, that has delivered only 27 percent of its product as land reform, the rest going to monetary compensation mainly in urban areas. Thus it can be argued that restitution has been more successful as a program to promote reconciliation along the lines of the Truth and Reconciliation Commission, than as a land reform program, especially if one regards land reform as the restoration of rural land to the indigenous population. There have also been some successful attempts by the Commission, such as in the case of PELCRA, to integrate the processing of its claims with local government planning processes, but progress in this direction remains patchy.
- Full Text:
- Date Issued: 2004
An explication of the dual nature of narcissism in Patrick White's novel The solid mandala
- Authors: Watts, Jacqueline Anne
- Date: 1989
- Subjects: White, Patrick, 1912-1990. The Solid Mandala White, Patrick, 1912-1990 -- Criticism and interpretation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2907 , http://hdl.handle.net/10962/d1002072
- Description: The focus of this thesis has been to engage in a hermeneutic dialogue with Patrick White's novel The solid mandala, to provide an explication of the dual nature of narcissistic wounding. To this end a brief review of Patrick White's novels is given, which traces a thematic development of the hero's strivings to attain wholeness and merger with an idealized image. This struggle is understood to reflect man's strivings to return to a state of omnipotent fusion with the maternal image, be it God, nature, the idealized other, or the self. Literature which reflects the dual nature of narcissistic wounding is reviewed, and the concept of narcissism is traced from the historical roots of Freud, to current understandings of the function and experience of narcissism. Emphasis is given to understanding the experiential nature of narcissistic wounding. As such it is implied that narcissism is a normal developmental component which requires the facilitation of containment and reflection for its transformation into appropriate adult functioning. The importance of the maternal environment is discussed, together with the various theoretical conceptualizations of the consequences of failure of the environment. The hermeneutic dialogue with the novel's description of the experiences of the twins, Waldo and Arthur provides the basis for an amplification of the experience of narcissistic wounding. This amplification is used as clinical material from which a number of psychoanalytic formulations are drawn. These formulations are supported by a number of clinical examples from the researcher's own practice. There appears to be evidence for the value of focusing on the dual nature of the experience of narcissistic wounding. This focus reveals two aspects of experience, a damaged, positive, libidinal aspect and a defensive, pathological destructive aspect. Amplification of these two aspects of experience contribute to further the understanding of the conflictual experience of narcissistic wounding, and suggest the necessity for such an understanding for effective therapeutic intervention
- Full Text:
- Date Issued: 1989
- Authors: Watts, Jacqueline Anne
- Date: 1989
- Subjects: White, Patrick, 1912-1990. The Solid Mandala White, Patrick, 1912-1990 -- Criticism and interpretation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2907 , http://hdl.handle.net/10962/d1002072
- Description: The focus of this thesis has been to engage in a hermeneutic dialogue with Patrick White's novel The solid mandala, to provide an explication of the dual nature of narcissistic wounding. To this end a brief review of Patrick White's novels is given, which traces a thematic development of the hero's strivings to attain wholeness and merger with an idealized image. This struggle is understood to reflect man's strivings to return to a state of omnipotent fusion with the maternal image, be it God, nature, the idealized other, or the self. Literature which reflects the dual nature of narcissistic wounding is reviewed, and the concept of narcissism is traced from the historical roots of Freud, to current understandings of the function and experience of narcissism. Emphasis is given to understanding the experiential nature of narcissistic wounding. As such it is implied that narcissism is a normal developmental component which requires the facilitation of containment and reflection for its transformation into appropriate adult functioning. The importance of the maternal environment is discussed, together with the various theoretical conceptualizations of the consequences of failure of the environment. The hermeneutic dialogue with the novel's description of the experiences of the twins, Waldo and Arthur provides the basis for an amplification of the experience of narcissistic wounding. This amplification is used as clinical material from which a number of psychoanalytic formulations are drawn. These formulations are supported by a number of clinical examples from the researcher's own practice. There appears to be evidence for the value of focusing on the dual nature of the experience of narcissistic wounding. This focus reveals two aspects of experience, a damaged, positive, libidinal aspect and a defensive, pathological destructive aspect. Amplification of these two aspects of experience contribute to further the understanding of the conflictual experience of narcissistic wounding, and suggest the necessity for such an understanding for effective therapeutic intervention
- Full Text:
- Date Issued: 1989
Continuous-flow dynamic dialysis and its application to collagen-ligand interactions
- Authors: Sparrow, Neil Arthur
- Date: 1983
- Subjects: Collagen Ligands (Biochemistry) Ligand binding (Biochemistry) Protein-protein interactions Tannins
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4297 , http://hdl.handle.net/10962/d1004617
- Description: Studies undertaken to investigate the binding of low molecular mass analogues of polyphenolic vegetable tannins to collagen have prompted the development of a new method to investigate protein-ligand interactions. This method, the continuous-flow dynamic dialysis method (CFDD), differs from conventional dialysis procedures used for protein-ligand binding studies. In this method, the ligand concentration in the diffusate is monitored automatically at successive closely spaced time intervals while being continuously eluted from the dialysis cell. The primary data obtained by this method consists of a series of spectrophotometric absorbance measurements representing the ligand concentration in the sink compartment of a dialysis cell. This primary data is recorded by means of a data logging device onto a punched paper tape for subsequent computer processing. Two original methods are presented for analysing the primary data to extract the protein-ligand binding isotherm. The first of these is a direct analysis which relies on Fick's first law of diffusion. In this method it is necessary to establish, by means of a control experiment, a value for the ligand permeation constant. This is used in a subsequent analysis to establish a relationship between the measured rate of diffusion of the ligand from a protein-ligand mixture and the concentration of unbound ligand which is in equilibrium with the protein-ligand complex. The protein-ligand binding isotherm is obtained from parametric equations which give the quantity of ligand bound to the protein and the concentration of unbound ligand in the sample compartment as functions of time. The second method, which is more general, utilizes the same primary data but is based on establishing a system transfer function to characterise the dialysis and eluting processes. This analysis depends on the linearity of the system and utilizes numerical laplace transforms of the primary data sets obtained from control and protein-ligand dialyses. Laplace transforms are used to effect a deconvolution of the transfer function from the primary data and yield the concentration of ligand in equilibrium with the protein-ligand complex. This procedure yields, simultaneously, both the total ligand concentration and the concentration of unbound ligand in the protein compartment of the dialysis cell. These quantities are used to establish the binding isotherm for the protein ligand system. Numerical inversion of the laplace transforms in this analysis is effected by their reduction to Fourier series. The experimental reliability of the continuous-flow dynamic dialysis method, and validity of the two analytical methods used to derive a binding isotherm from dialysis data are evaluated from studies of the binding of phenol red to bovine serum albumin (BSA) at 15⁰, 20⁰ and 25⁰ C, as well as from simulated binding curves generated by the numerical solution of the differential equations used to describe the dialysis and elution process in terms of a two-site Scatchard binding model. The method is used to investigate the binding to collagen of a series of low molecular mass phenolic compounds which can be isolated from Wattle and Quebracho vegetable tannin extracts. These compounds can be considered as monomeric precursor analogues of the polymeric vegetable tannins. The binding of these ligands to collagen is shown to be characterised by high capacity, low affinity binding in which the uptake of ligand by the protein increases linearly with increasing ligand concentration. Collagen exhibits no indication of site saturation for these ligands over the experimentally accessible concentration ranges investigated.
- Full Text:
- Date Issued: 1983
- Authors: Sparrow, Neil Arthur
- Date: 1983
- Subjects: Collagen Ligands (Biochemistry) Ligand binding (Biochemistry) Protein-protein interactions Tannins
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4297 , http://hdl.handle.net/10962/d1004617
- Description: Studies undertaken to investigate the binding of low molecular mass analogues of polyphenolic vegetable tannins to collagen have prompted the development of a new method to investigate protein-ligand interactions. This method, the continuous-flow dynamic dialysis method (CFDD), differs from conventional dialysis procedures used for protein-ligand binding studies. In this method, the ligand concentration in the diffusate is monitored automatically at successive closely spaced time intervals while being continuously eluted from the dialysis cell. The primary data obtained by this method consists of a series of spectrophotometric absorbance measurements representing the ligand concentration in the sink compartment of a dialysis cell. This primary data is recorded by means of a data logging device onto a punched paper tape for subsequent computer processing. Two original methods are presented for analysing the primary data to extract the protein-ligand binding isotherm. The first of these is a direct analysis which relies on Fick's first law of diffusion. In this method it is necessary to establish, by means of a control experiment, a value for the ligand permeation constant. This is used in a subsequent analysis to establish a relationship between the measured rate of diffusion of the ligand from a protein-ligand mixture and the concentration of unbound ligand which is in equilibrium with the protein-ligand complex. The protein-ligand binding isotherm is obtained from parametric equations which give the quantity of ligand bound to the protein and the concentration of unbound ligand in the sample compartment as functions of time. The second method, which is more general, utilizes the same primary data but is based on establishing a system transfer function to characterise the dialysis and eluting processes. This analysis depends on the linearity of the system and utilizes numerical laplace transforms of the primary data sets obtained from control and protein-ligand dialyses. Laplace transforms are used to effect a deconvolution of the transfer function from the primary data and yield the concentration of ligand in equilibrium with the protein-ligand complex. This procedure yields, simultaneously, both the total ligand concentration and the concentration of unbound ligand in the protein compartment of the dialysis cell. These quantities are used to establish the binding isotherm for the protein ligand system. Numerical inversion of the laplace transforms in this analysis is effected by their reduction to Fourier series. The experimental reliability of the continuous-flow dynamic dialysis method, and validity of the two analytical methods used to derive a binding isotherm from dialysis data are evaluated from studies of the binding of phenol red to bovine serum albumin (BSA) at 15⁰, 20⁰ and 25⁰ C, as well as from simulated binding curves generated by the numerical solution of the differential equations used to describe the dialysis and elution process in terms of a two-site Scatchard binding model. The method is used to investigate the binding to collagen of a series of low molecular mass phenolic compounds which can be isolated from Wattle and Quebracho vegetable tannin extracts. These compounds can be considered as monomeric precursor analogues of the polymeric vegetable tannins. The binding of these ligands to collagen is shown to be characterised by high capacity, low affinity binding in which the uptake of ligand by the protein increases linearly with increasing ligand concentration. Collagen exhibits no indication of site saturation for these ligands over the experimentally accessible concentration ranges investigated.
- Full Text:
- Date Issued: 1983
Semantiese velde en die onderrig en aanleer van Xhosa-woordeskat
- Authors: Venter, Johannes Andreas
- Date: 1980
- Subjects: Xhosa language -- Semantics , Xhosa language -- Vocabulary , Xhosa language -- Study and teaching
- Language: Afrikaans
- Type: Thesis , Masters , MA
- Identifier: vital:3606 , http://hdl.handle.net/10962/d1003814 , Xhosa language -- Semantics , Xhosa language -- Vocabulary , Xhosa language -- Study and teaching
- Description: Uit Inleiding: Hoe belangrik is die aanleer van woordeskat by die verwerwing van 'n vreemde taal? Indien dit van besondere belang is, kan met reg gevra word: watter beginsels moet in ag geneem word by die opstel van metodes en tegnieke om die aanleer van die woordeskat met optimum effektiwiteit te laat plaasvind? Wat is die teoretiese basis vir sulke metodes en tegnieke? Hierdie is enkele vrae wat in hierdie ondersoek aan die orde sal kom. Die begrip "semantiese velde" of "betekenisvelde" is 'n idee wat in die jongste tyd heelwat aandag geniet by linguiste. Die konsep "betekenisveld" veronderstel twee kenmerke van die leksikon: 1. Dat die betekenisaspek van elke individuele leksikale item, kragtens kontras bestaan en dat hierdie kontras tussen betekeniskomponente van leksikale items in die leksikon teregkom, veral binne 'n betekenisveldsiening. 2. Dat die leksikon kragtens die relasies tussen die leksikale items 'n georganiseerde en gestruktureerde versameling is. In ons ondersoek sal dit dus hoofsaaklik gaan oor: 1. Bestaande metodes en tegnieke om woordeskat te onderrig. 2. Bestaande toerieë oor die gestruktureerdheid van woordeskat. 3. Die moontlikhede wat hierdie teorieë inhou, om die onderrig van woordeskat meer effektief te laat plaasvind.
- Full Text:
- Date Issued: 1980
- Authors: Venter, Johannes Andreas
- Date: 1980
- Subjects: Xhosa language -- Semantics , Xhosa language -- Vocabulary , Xhosa language -- Study and teaching
- Language: Afrikaans
- Type: Thesis , Masters , MA
- Identifier: vital:3606 , http://hdl.handle.net/10962/d1003814 , Xhosa language -- Semantics , Xhosa language -- Vocabulary , Xhosa language -- Study and teaching
- Description: Uit Inleiding: Hoe belangrik is die aanleer van woordeskat by die verwerwing van 'n vreemde taal? Indien dit van besondere belang is, kan met reg gevra word: watter beginsels moet in ag geneem word by die opstel van metodes en tegnieke om die aanleer van die woordeskat met optimum effektiwiteit te laat plaasvind? Wat is die teoretiese basis vir sulke metodes en tegnieke? Hierdie is enkele vrae wat in hierdie ondersoek aan die orde sal kom. Die begrip "semantiese velde" of "betekenisvelde" is 'n idee wat in die jongste tyd heelwat aandag geniet by linguiste. Die konsep "betekenisveld" veronderstel twee kenmerke van die leksikon: 1. Dat die betekenisaspek van elke individuele leksikale item, kragtens kontras bestaan en dat hierdie kontras tussen betekeniskomponente van leksikale items in die leksikon teregkom, veral binne 'n betekenisveldsiening. 2. Dat die leksikon kragtens die relasies tussen die leksikale items 'n georganiseerde en gestruktureerde versameling is. In ons ondersoek sal dit dus hoofsaaklik gaan oor: 1. Bestaande metodes en tegnieke om woordeskat te onderrig. 2. Bestaande toerieë oor die gestruktureerdheid van woordeskat. 3. Die moontlikhede wat hierdie teorieë inhou, om die onderrig van woordeskat meer effektief te laat plaasvind.
- Full Text:
- Date Issued: 1980
A dielectric and spectroscopic study of molecular association in solutions of alcohols
- Authors: Campbell, Colin
- Date: 1975
- Subjects: Alcohols , Dielectrics , Spectrum analysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4454 , http://hdl.handle.net/10962/d1010424
- Description: This study is concerned with the association characteristics of solutions of alcohols in some non-polar solvents. The permittivities at 2 MHz and 25°C for solutions of the straight chain octanols in cyclohexane, carbon tetrachloride and benzene have been examined over the entire solute concentration range, with particular attention -1 being paid to the range below 0.1 molℓ⁻¹ By applying the Kirkwood- Fröhlich equation to these data, the apparent dipole moments of the alcohols as a function of concentration have been evaluated. These concentration dependencies have been correlated with infrared absorption results on the same systems to provide information on the sizes and configurations of the proposed hydrogen bonded multimers. It is concluded that, at very low solute concentrations, the alcohol molecules exist as monomers; but with increasing concentration, two types of hydrogen bonded multimers are formed, the first (at low concentrations) being of high dipole moment and the second (at higher concentrations) being of low dipole moment. At high concentrations, the molecules associate to form a three-dimensional network. Attempts have been made to determine equilibrium parameters for molecular models which are consistent with the qualitative understanding of the association behaviour. These parameters were obtained by applying least-squares, curve-fitting techniques to the low concentration permittivity data. A similar investigation has been conducted on solutions of 2,3,4-trimethyl-3-pentanol in the same solvents. The steric hindrance around the hydroxyl group of this alcohol modifies the association behaviour so that a three-dimensional network does not form at high solute concentrations. Proton magnetic resonance chemical shifts for the hydroxyl proton of this alcohol in carbon tetrachloride solutions have been measured. Attempts have also been made to determine equilibrium parameters which describe formation of the hydrogen bonded multimers. To extend this study to include solutes other than octanols, similar experiments have been conducted on solutions of t-butanol in hexadecane, a system which has recently been investigated by other workers using different experimental techniques. The association behaviour of this system is qualitatively similar to that of the straight-chain octanols. The combination of permittivity and infrared measurements, although proving extremely powerful in interpreting the association characteristics of dilute alcohol solutions, is less adequate at high solute concentrations. Attention was therefore directed towards dielectric relaxation and viscosity studies to investigate concentrated solutions. The relaxation times at 20°C of the low frequency dispersion have been measured for solutions of 1-propanol, 1-butanol, 1-hexanol, 1-octanol and 1-decanol in cyclohexane using time domain reflectometry techniques. Similar measurements have also been made on solutions of 1-butanol and 1-octanol in carbon tetrachloride and in benzene. The concentration dependence of the viscosities of certain of these systems has also been examined in an independent study. The ratio of the dielectric relaxation time to the viscosity, the "reduced relaxation time", is qualitatively similar for each system studied. This similarity leads to an explanation of the molecular process responsible for the low frequency dispersion in terms of the proximity of the hydroxyl groups in concentrated alcohol solutions and the fraction of the groups which are not involved in hydrogen bonding.
- Full Text:
- Date Issued: 1975
- Authors: Campbell, Colin
- Date: 1975
- Subjects: Alcohols , Dielectrics , Spectrum analysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4454 , http://hdl.handle.net/10962/d1010424
- Description: This study is concerned with the association characteristics of solutions of alcohols in some non-polar solvents. The permittivities at 2 MHz and 25°C for solutions of the straight chain octanols in cyclohexane, carbon tetrachloride and benzene have been examined over the entire solute concentration range, with particular attention -1 being paid to the range below 0.1 molℓ⁻¹ By applying the Kirkwood- Fröhlich equation to these data, the apparent dipole moments of the alcohols as a function of concentration have been evaluated. These concentration dependencies have been correlated with infrared absorption results on the same systems to provide information on the sizes and configurations of the proposed hydrogen bonded multimers. It is concluded that, at very low solute concentrations, the alcohol molecules exist as monomers; but with increasing concentration, two types of hydrogen bonded multimers are formed, the first (at low concentrations) being of high dipole moment and the second (at higher concentrations) being of low dipole moment. At high concentrations, the molecules associate to form a three-dimensional network. Attempts have been made to determine equilibrium parameters for molecular models which are consistent with the qualitative understanding of the association behaviour. These parameters were obtained by applying least-squares, curve-fitting techniques to the low concentration permittivity data. A similar investigation has been conducted on solutions of 2,3,4-trimethyl-3-pentanol in the same solvents. The steric hindrance around the hydroxyl group of this alcohol modifies the association behaviour so that a three-dimensional network does not form at high solute concentrations. Proton magnetic resonance chemical shifts for the hydroxyl proton of this alcohol in carbon tetrachloride solutions have been measured. Attempts have also been made to determine equilibrium parameters which describe formation of the hydrogen bonded multimers. To extend this study to include solutes other than octanols, similar experiments have been conducted on solutions of t-butanol in hexadecane, a system which has recently been investigated by other workers using different experimental techniques. The association behaviour of this system is qualitatively similar to that of the straight-chain octanols. The combination of permittivity and infrared measurements, although proving extremely powerful in interpreting the association characteristics of dilute alcohol solutions, is less adequate at high solute concentrations. Attention was therefore directed towards dielectric relaxation and viscosity studies to investigate concentrated solutions. The relaxation times at 20°C of the low frequency dispersion have been measured for solutions of 1-propanol, 1-butanol, 1-hexanol, 1-octanol and 1-decanol in cyclohexane using time domain reflectometry techniques. Similar measurements have also been made on solutions of 1-butanol and 1-octanol in carbon tetrachloride and in benzene. The concentration dependence of the viscosities of certain of these systems has also been examined in an independent study. The ratio of the dielectric relaxation time to the viscosity, the "reduced relaxation time", is qualitatively similar for each system studied. This similarity leads to an explanation of the molecular process responsible for the low frequency dispersion in terms of the proximity of the hydroxyl groups in concentrated alcohol solutions and the fraction of the groups which are not involved in hydrogen bonding.
- Full Text:
- Date Issued: 1975
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