Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 20 for “"Selective extraction"”.
-
Selective extraction of colorful proteins using reverse micelles
… continuous separation method of liquid-liquid extraction using reverse micelles is one such technique. While this technique has been researched in the past, previous studies lack information about realistic complex protein mixtures.</p> <p>Through this study optimum conditions were found for …
-
Development of Dithiobiuret-Based Ligands for Coordination and Selective Extraction of Precious Metals
… the metal can be isolated and recovered. Solvent extraction is commonly employed for this purpose; however, it is often limited by a lack of selectivity or by the necessary use of environmentally damaging organic solvents. Therefore, it is the goal of this research to develop novel extractants …
-
Optimisation of selective extraction techniques as a tool for geochemical mapping in the Southern Africa region
… may be ascribed to the use of various partial extraction techniques,without a profound understanding of the regolith components and their composition. This investigation therefore focuses on the use of hydroxylamine partial extraction geochemistry for geochemical mapping in regolith over two …
-
The Structure Function Relationship of Silica Polyamine Composites
… with sodium chloroacetate and other metal selective ligands in higher yield, resulting in a material with substantially improved copper ion capacities. Silica polyamine composites have also been modified with a novel series of amino acid chelating ligands for the purpose of selective …
-
The Structure Function Relationship of Silica Polyamine Composites
… with sodium chloroacetate and other metal selective ligands in higher yield, resulting in a material with substantially improved copper ion capacities. Silica polyamine composites have also been modified with a novel series of amino acid chelating ligands for the purpose of selective …
-
The solvent extraction of CU (II) from chloride solutions with certain non-chelating nitrogen donor ligands
The extraction of copper from chloride solutions with some aliphatic oximes as well as some pyridine carboxylates was studied and the complexes formed in the organic phase identified. The association of octanal oxime in toluene was taken into account in the extraction studies and formation …
-
Synthesis, characterization and potential chromatographic separation of palladium and platinum complexes of N,N-Dialkyl-N'-Benzoylthioureas
… Ni(II) and Cu(II). To this end the possible selective extraction of these complexes from acidic aqueous phases was examined. This layer normal phase chromatography has been mainly used, using a variety of organic phases as eluent. A preliminary investigation of the suitability of using normal …
-
The amino acid sequence of chicken histone F3
… (III) from chicken erythrocytes was isolated by selective extraction from nucleoprotein with ethanolic-HCl and purified by a single gel filtration step. This protein was found to be homogeneous by the following criteria: gel filtration, electrophoretic mobility, N- and C-terminal amino acid …
-
On the electrolytic nature of molten aluminum and rare earth oxides
… molten lanthana-yttria. The results revealed selective extraction of lanthanum and indicated that molten lanthana-yttria does not exhibit ideal mixing behavior, contradicting previous predictions. However, data interpretation in multicomponent electrolyte compositions were challenged primarily …
-
Acoustic emulsions of liquid, near-critical carbon dioxide and water : application to synthetic chemistry through reaction engineering
… been impressive, for example scCO2 is used as a selective extraction solvent in several commercial processes. By comparison, development of scCO2 as a reaction solvent has been much less successful due to its limited solvation power. Furthermore, the rates of reactions conducted in scCO2 tend to …
-
Investigation of Acrylated Alkyds
… Magnetic Resonance (2D gHMQC NMR), 1H NMR, selective extraction, and gas chromatography were conducted to study each system. For the stearic alkyd model systems, evidence of grafting by hydrogen abstraction from glyceride unit was found. It was surmised that the acrylic macroradical combines …
-
Development of rapid techniques based on selective dissolution for the determination of the precious metals in geological samples
… samples is described. The technique is based on selective aqua regia acid leach followed by a selective extraction (using diphenylthiourea and 1,2-dichloroethane) to separate the PGE and Au as a group from concomitant matrix elements. Organic extracts and aqueous raffinates were analysed by …
-
Supercritical fluid extraction as a sample preparation technique for the isolation of polar pharmaceutical compounds
The low polarity of the supercritical fluid extraction (SFE) solvent, CO₂, causes problems when applying this technique to polar compounds. The objective of this research was to expand the applicability of SFE to include polar compounds. The first phase of this research investigated "inverse SFE", …
-
Stimuli-Induced Structural Transformations of Metal–Organic Cages
… molecular sensing, targeted delivery, and extractions. This thesis focuses on the design and synthesis of stimuli-responsive MOCs, exploring how stimuli drive structural reorganization and bring potential applications. Three distinct MOC systems which can respond to different stimuli were …
-
Competition Between Different Non-Covalent Interactions in Cluster Ions
… The role of competing interactions in the size-selective extraction of ions from solution was investigated in M+(12C4)(H2O)n species where 12C4 represents 12-crown-4 ether. The results indicate that the hydrogen bonds around the Li+(12C4) complex are significantly stronger than those around the …
-
Selective Ion Separations Using Shock Electrodialysis
… face a number of difficult challenges in the selective extraction of high-value ionic species from dilute aqueous solutions. Important examples include the selective removal of trace pollutants, such as toxic heavy metal ions, from industrial effluents; the fractionation of chemically and …
-
New extraction protocols for the determination of endocrine disrupting compounds in samples of environmental and agri-food interest
… and miniaturised techniques which allow a high extraction efficiency, selectivity and sensitivity, with low consumption of reagents and organic solvents, have become important alternatives to address their analysis. Thus, in this PhD Thesis, new effective and sensitive analytical methodologies …
-
Deep Eutectic Solvents Synthesis, Characterization and Applications in Pretreatment of Lignocellulosic Biomass
… and lignin was evaluated. The DESs selective dissolution of lignin was further explored and an extraction method optimized to selectively extract lignin from lignocellulosic biomass. The DESs extracted up to 80% of the lignin from PCG and SWG biomass was achieved. The extracted …
-
Síntesis, caracterización, propiedades y aplicaciones de nuevas poliamidas aromáticas con subestructuras benzoéter corona y benzopodandos en la cadena lateral
… development of fixed-site carrier membranes for selective transport or manufacture of cation sensitive sensors.
-
The development of a mathematical model for the bioextraction of the critical raw material magnesium from mine waste using acidithiobacillus caldus
… mine wastes, ultimately maximising magnesium extraction while minimising reliance on synthetic acid. In the absence of experimental data on the dissolution profiles of the waste, kinetic models were developed to describe the leaching of individual minerals: periclase, calcite, and goethite. …