An ion imprinted polymer for the selective extraction of mercury (II) ions in aqueous media
- Authors: Batlokwa, Bareki Shima
- Date: 2010 , 2013-07-18
- Subjects: Mercury , Metal ions , Imprinted polymers , Polymerization
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4294 , http://hdl.handle.net/10962/d1004541 , Mercury , Metal ions , Imprinted polymers , Polymerization
- Description: This thesis presents the application of an imprinted mercury(lI) polymer that we synthesized by copolymerizing the functional and cross-linking monomers, N'-[3-(Trimethoxysilyl)propyl] diethylenetriamine (TPET) and tetraethylorthosilicate (TEOS) in the presence of mercury (II) ions as template. A bulk polymerization method following a double-imprinting procedure and employing hexadecyltrimethylammonium bromide (CTAB), as a second template to improve the efficiency of the polymer was employed in the synthesis. The imprinted polymer particles were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and their average size determined by screen analysis using standard test sieves. The relative selective coefficients (k') of the imprinted polymer evaluated from selective binding studies between Hg ²⁺and Cu²⁺ or Hg²⁺ and Cd²⁺, were 10588 and 3147, respectively. These values indicated highly favored Hg²⁺ extractions over the two competing ions. Application of the polymer to various real water samples (tap, sea, river, pulverized coal solution, treated and untreated sewerage from the vicinity of Grahamstown in South Africa) showed high extraction efficiencies (EEs) of Hg²⁺ ions; (over 84% in all cases) as evaluated from the detected unextracted Hg²⁺ ions by inductively coupled plasma optical emission spectroscopy (ICP-OES). The limit of detection (LOD, 3ơ) of the method was evaluated to be 0.036 ng ml⁻¹ and generally the data (n=10) had percentage relative standard deviation (%RSD) of less than 4%. These findings indicate that the double-imprinted polymer has potential to be used as an efficient extraction material for the selective pre-concentration of mercury(lI) ions in aqueous environments. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2010
- Authors: Batlokwa, Bareki Shima
- Date: 2010 , 2013-07-18
- Subjects: Mercury , Metal ions , Imprinted polymers , Polymerization
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4294 , http://hdl.handle.net/10962/d1004541 , Mercury , Metal ions , Imprinted polymers , Polymerization
- Description: This thesis presents the application of an imprinted mercury(lI) polymer that we synthesized by copolymerizing the functional and cross-linking monomers, N'-[3-(Trimethoxysilyl)propyl] diethylenetriamine (TPET) and tetraethylorthosilicate (TEOS) in the presence of mercury (II) ions as template. A bulk polymerization method following a double-imprinting procedure and employing hexadecyltrimethylammonium bromide (CTAB), as a second template to improve the efficiency of the polymer was employed in the synthesis. The imprinted polymer particles were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and their average size determined by screen analysis using standard test sieves. The relative selective coefficients (k') of the imprinted polymer evaluated from selective binding studies between Hg ²⁺and Cu²⁺ or Hg²⁺ and Cd²⁺, were 10588 and 3147, respectively. These values indicated highly favored Hg²⁺ extractions over the two competing ions. Application of the polymer to various real water samples (tap, sea, river, pulverized coal solution, treated and untreated sewerage from the vicinity of Grahamstown in South Africa) showed high extraction efficiencies (EEs) of Hg²⁺ ions; (over 84% in all cases) as evaluated from the detected unextracted Hg²⁺ ions by inductively coupled plasma optical emission spectroscopy (ICP-OES). The limit of detection (LOD, 3ơ) of the method was evaluated to be 0.036 ng ml⁻¹ and generally the data (n=10) had percentage relative standard deviation (%RSD) of less than 4%. These findings indicate that the double-imprinted polymer has potential to be used as an efficient extraction material for the selective pre-concentration of mercury(lI) ions in aqueous environments. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2010
The presentation of the orphan child in eighteenth and early nineteenth century English literature in a selection of William Blake's 'Songs of innocence and experience', and in Charlotte Brontë's 'Jane Eyre', and Emily Brontë's 'Wuthering Heights'
- Authors: Singh, Jyoti
- Date: 2010 , 2013-07-18
- Subjects: Blake, William, 1757-1827 -- Songs of innocence and of experience -- Characters -- Orphans Blake, William, 1757-1827 -- Criticism and interpretation Brontë, Charlotte, 1816-1855 -- Jane Eyre -- Characters -- Orphans Brontë, Charlotte, 1816-1855 -- Criticism and interpretation Brontë, Emily, 1818-1848 -- Wuthering Heights -- Characters -- Orphans Brontë, Emily, 1818-1848 -- Criticism and interpretation Orphans in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2267 , http://hdl.handle.net/10962/d1005628
- Description: This thesis is a study of the presentation of the orphan child in eighteenth and early nineteenth century English literature, and focuses on William Blake's Songs of Innocence and Experience, Charlotte Bronte's Jane Eyre, and Emily Bronte's Wuthering Heights. It is concerned with assessing the extent to which the orphan children in each of the works are liberated from familial and social constraints and structures and to what end. Chapter One examines the major thematic concern of the extent to which the motif of the orphan child represents a wronged innocent, and whether this symbol can also, or alternatively, be presented as a revolutionary force that challenges society's status quo in Blake's Songs of Innocence and Experience. Chapter Two considers the significance of the child "lost" and "found", which forms the explicit subject of six of Blake's Songs of Innocence and Experience and explores the treatment of these conditions, and their differences and consequences for the children concerned. Chapter Three focuses on Charlotte Bronte's depiction of the orphan in Jane Eyre, which presents two models of the orphan child: the protagonist Jane, and Helen Burns. The chapter examines these two models and their responses to orphan-hood in a hostile world where orphans are mistreated by family and society alike. Chapter Four determines whether the orphan constitutes a subversive threat to the family in Emily Bronte's Wuthering Heights and also explores the notion that, although orphan-hood often entails liberation from adult guardians, it also comprises vulnerability and exposure. The thesis concludes by considering the extent to which orphan-hood can involve a form of liberation from the confines of social structures, and what this liberation constitutes for each of the three authors.
- Full Text:
- Date Issued: 2010
- Authors: Singh, Jyoti
- Date: 2010 , 2013-07-18
- Subjects: Blake, William, 1757-1827 -- Songs of innocence and of experience -- Characters -- Orphans Blake, William, 1757-1827 -- Criticism and interpretation Brontë, Charlotte, 1816-1855 -- Jane Eyre -- Characters -- Orphans Brontë, Charlotte, 1816-1855 -- Criticism and interpretation Brontë, Emily, 1818-1848 -- Wuthering Heights -- Characters -- Orphans Brontë, Emily, 1818-1848 -- Criticism and interpretation Orphans in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2267 , http://hdl.handle.net/10962/d1005628
- Description: This thesis is a study of the presentation of the orphan child in eighteenth and early nineteenth century English literature, and focuses on William Blake's Songs of Innocence and Experience, Charlotte Bronte's Jane Eyre, and Emily Bronte's Wuthering Heights. It is concerned with assessing the extent to which the orphan children in each of the works are liberated from familial and social constraints and structures and to what end. Chapter One examines the major thematic concern of the extent to which the motif of the orphan child represents a wronged innocent, and whether this symbol can also, or alternatively, be presented as a revolutionary force that challenges society's status quo in Blake's Songs of Innocence and Experience. Chapter Two considers the significance of the child "lost" and "found", which forms the explicit subject of six of Blake's Songs of Innocence and Experience and explores the treatment of these conditions, and their differences and consequences for the children concerned. Chapter Three focuses on Charlotte Bronte's depiction of the orphan in Jane Eyre, which presents two models of the orphan child: the protagonist Jane, and Helen Burns. The chapter examines these two models and their responses to orphan-hood in a hostile world where orphans are mistreated by family and society alike. Chapter Four determines whether the orphan constitutes a subversive threat to the family in Emily Bronte's Wuthering Heights and also explores the notion that, although orphan-hood often entails liberation from adult guardians, it also comprises vulnerability and exposure. The thesis concludes by considering the extent to which orphan-hood can involve a form of liberation from the confines of social structures, and what this liberation constitutes for each of the three authors.
- Full Text:
- Date Issued: 2010
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