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 “"Tellurides."”.
-
A study of the flotation behaviour of Pt and Pd tellurides and arsenides
… PGE bearing minerals in the Platreef, PGE tellurides are the most abundant, occurring in excess of 30% in terms of PGM relative abundance, followed by PGE arsenides at 21%. As is well know, flotation is a key process in the upgrading and recovery of such minerals from the mined ores. The …
-
An investigation into the floatability of platinum group arsenides and tellurides under varying collector and solution chemistries
Platinum group tellurides and arsenides are the most economically important and abundant platinum group minerals (PGM) in the Platreef ore deposit. It has been found that there are major losses of these minerals during flotation, with most of the losses attributed to sperrylite (PtAs2). This study …
-
Surface characterisation and flotation behaviour of the platinum and palladium arsenide, telluride and sulphide mineral species
… the most abundant. The predominant PGMs are the tellurides, arsenides, alloys and sulphides. The Pt and Pd tellurides contribute between 20-45% of the PGMs present in the Platreef ore followed by the alloys (26%), arsenides (21%) and sulphides (19%). Flotation is used in the processing of the …
-
Temperature And Pressure Effects On Elastic Properties Of Relaxor Ferroelectrics And Thermoelectrics: A Resonant Ultrasound Spectroscopy Study
… between (TC and TB). Thermoelectric lanthanum tellurides and skutterudites are being investigated by NASA's Jet Propulsion Laboratory for advanced thermoelectric generates (TEGs). Effects of nickel (Ni) doping on elastic properties of lanthanum tellurides at elevated temperatures were …
-
An Investigation of the Structures, Properties and Possible Applications of Complexes of Metals with Organotellurium Compounds
… ability was investigated. It is found that tellurides form quite stable complexes with metals of class (b) or softish character. Copper(I), rhodium(III) andrhodium (I) complexes with diaryltellurides were synthesised. Their structure, properties and uses were investigated with the help of …
-
Noble gases anomalies in terrestrial ores and meteorites
… Sweden and 2.83 x 10²¹ years from analysis of tellurides from Kalgoorlie, Australia. 2. The ratio of the double beta-decay half-life of ¹²⁸Te relative to that of ¹³⁰Te is ≥ 108 and ≥ 293 for Boliden tellurobismuthite and Kalgoorlie tellurides, respectively. 3. Selenium minerals and tellurium …
-
An electrochemical investigation of platinum group minerals
… (2007) investigated the flotation of PGE tellurides, sulphides and arsenides. The study highlighted that the mechanisms with which these minerals interact with collectors and with copper sulphate was poorly understood. It is as a result of the findings of Shackleton's work that this study …
-
Semiconductor nanocrystal colloids : manganese doped cadmium selenide, (core)shell composites for biological labeling, and highly fluorescent cadmium telluride
… useful fluorescent labels. Stable phosphine tellurides are prepared using hexapropylphosphorus triamide (HPPT). This precursor is used to prepare CdTe nanocrystals that display room temperature quantum yields up to 70%. The CdTe growth is investigated by absorption and emission spectroscopy. …
-
Quantum oscillations in Dirac semimetals
… these materials. Among the many candidates, the tellurides NbTe₄, TaPtTe₅ and TaNiTe₅ appear to provide a promising platform for the study of such topological properties. To probe their band structure and its corresponding Fermi surface, quantum oscillations have proven very useful as they …
-
Synthesis, Characterization and Electrochemical Properties of Gold Nanomolecules
… exchange with other chalcogenide ligands like tellurides is discussed briefly. Chapter 3 covers the core size conversion reactions in gold nanomolecules. When gold nanomolecules are etched in excess thiols at elevated temperatures, some of the gold nanomolecules convert to a different size. …
-
Copper mineralization in the Coed-Y-Brenin Porphyry Copper Deposit, North Wales: Mineralogy and Textures
… a difference was that Miller found electrum and tellurides, whereas this study did not; instead, native gold was found.
-
The geology and geochemistry of the Omai goldfield, Guyana
… commonly associated with galena and microscopic tellurides. Provisional fluid inclusion studies have indicated that the parent hydrothermal fluid was H20-C02 -bearing (- 5.0 mol% CO2 ), of low salinity (0-1.8 wt. % NaCI equiv.) and moderate density (0.96 g/cm3). The depositional temperature of …
-
Synthesis and characterization of metal chalcogenide nanostructured materials for thermoelectric applications
… thermoelectric (TE) properties is reported. The tellurides, specifically PbTe and Bi⊂2⊂Te⊂3⊂ (Bi⊂2⊂Te⊂3⊂–Sb⊂2⊂Te⊂3⊂ alloys) were selected as these are well established TE materials in bulk form. The approaches used for nanostructuring are (1) sol-gel assembly of discrete nanoparticles of PbTe, …
-
The Porgera gold deposit, Papua New Guinea : geology, geochemistry and geochronology
… ore). Abundant visible gold occurs with Au-Ag-Ag-tellurides in these epithermal-style, vuggy, banded veins. Deposition of both types of ore is shown by K-Ar dating of sericite (illite) and roscoelite to have occurred within 1 Ma of the time of emplacement of the PIC at 6.0 ± 0.3 Ma (2a; K-Ar …
-
The Porgera gold deposit, Papua New Guinea : geology, geochemistry and geochronology
… ore). Abundant visible gold occurs with Au-Ag-Ag-tellurides in these epithermal-style, vuggy, banded veins. Deposition of both types of ore is shown by K-Ar dating of sericite (illite) and roscoelite to have occurred within 1 Ma of the time of emplacement of the PIC at 6.0 ± 0.3 Ma (2a; K-Ar …
-
An investigation of cyanide-based heap leaching for extracting precious metals from Platreef ore
… compared to other mineral forms such as certain tellurides and sulphides in the ore. Subsequently, efforts were made to investigate methods to improve the second stage leach process, in terms of Pt leaching from sperrylite, through further work on a pure mineral sample. The key focus was on …
-
Application of Thermomechanical Characterization Techniques to Bismuth Telluride Based Thermoelectric Materials
The thermoelectric properties of bismuth telluride based thermoelectric (TE) materials are well-characterized, but comparatively little has been published on the thermomechanical properties. In this paper, dynamic mechanical analysis (DMA) and differential scanning calorimetry data for bismuth …
-
Investigating the use of sodium silicate to improve the flotation performance of Platreef and UG2 PGE ores
… improved the recovery of PGE sulphides and PGE tellurides. These are believed to have been responsible for the recovery gains reported. However, sodium silicate appeared to negatively impact the floatability of PGE arsenides. The Platreef concentrates at 0 g/t and 2000 g/t sodium silicate were …
-
Laser beam induced current studies of Hg1-xCdxTe photodiodes
Laser-beam-induced-current (LBIC) is being investigated as a combined electro-optical (EO) alternative to individual electrical and optical based measurements of p-n junction photodiodes. The technique is non-destructive and employs a focused low-power laser beam that is scanned across the …