https://commons.ufh.ac.za/vital/access/manager/Index ${session.getAttribute("locale")} 5 https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26603 0.9. The release mechanism was confirmed using the Korsmeyer-Peppas model that revealed that most of the formulations exhibited anomalous transport kinetics with the release exponent, n, ranging from 0.5 Wed 12 May 2021 23:42:25 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26593 Wed 12 May 2021 23:23:43 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26731 Wed 12 May 2021 22:43:59 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5971 Wed 12 May 2021 20:35:27 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26623 Wed 12 May 2021 20:17:12 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:29538 Wed 12 May 2021 19:24:42 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26570 Wed 12 May 2021 18:40:26 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26576 Wed 12 May 2021 18:38:11 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:3527 Wed 12 May 2021 18:29:12 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26607 Wed 12 May 2021 17:33:21 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26751 Wed 12 May 2021 16:19:00 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26595 Wed 12 May 2021 16:05:26 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26581 Wed 12 May 2021 15:54:01 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:28605 Tue 13 Jun 2023 12:32:30 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26580 99 % in selectively extracting the metalloporphyrins. The impact of the template on the affinity of recognition for NTPP was evaluated. The results showed that the NTPP adsorption capacity increased as the molar ratio of NTPP to styrene was increased from 1:1 to 3:1. The optimal ratio of template to functional monomer which yielded the best specific affinity and highest recovery (99.9 %) was 3:1. The effects of trifluoroacetic acid (TFA), dichloromethane (DCM), dimethyl sulphoxide (DMSO), pentane (PEN) on electro-spinnability of the polymer solutions and the morphological appearance of the nanofibers were investigated. The imprinted nanofibers exhibited the same selectivity specialism for both NTPP and VTPP. A remarkable stability in relation to reusability was observed when imprinted nanofibers were used, as they could be reused nine times without incurring any significant loss in removal efficiency. The results were validated by analysing a certified reference material. The imprinted sorbents were therefore found to be selective sorbents that are well suited for handling trace metals in organic media.]]> Thu 13 May 2021 09:54:20 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:28540 Thu 13 May 2021 07:35:41 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:29380 20% habitat loss due to invasion). Upstream invasion by centrarchids isolated and fragmented P. afer populations into headwater refugia, while top down invasion by salmonids excluded B. trevelyani from invaded, more pristine stream reaches, by forcing the species into degraded unsuitable lower stream reaches. Predation also disrupted population processes such as adult dispersal for P. afer, and centrarchid-invaded zones acted as demographic sinks, where adults dispersing through invaded reaches were rapidly depleted. While the Mandela lineage of P. afer exhibited little within or between drainage genetic structuring, B. trevelyani was >4% divergent between drainages, and up to 2% divergent between streams within the Keiskamma River system (Chapter 7). The distribution of genetic diversity for B. trevelyani also indicated that the loss of diversity was imminent without immediate conservation interventions. This thesis has provided conclusive evidence that native fishes are vulnerable to invasion and that non-native predatory fishes have significant impacts on native fishes in Eastern Cape headwater streams. If management and conservation measures are implemented, the unwanted introduction and spread of non-native fishes may be restricted, allowing native fishes opportunities for recovery.]]> Thu 13 May 2021 07:28:56 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4700 Thu 13 May 2021 07:28:05 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26609 2.5Ga) and are located to the south and east of Lake Victoria on the Tanzania craton. The Tanzania Craton is surrounded by Usagaran 1.9 Ga rocks (the east African orogenic belt (EAO) better known as the Mozambique belt) to the east and the Ubendian belt to the south and west. Published reports show that the eastern part of the Tanzania Craton is dominated by the fragments of Archaean rocks. Metamorphism along East Africa and the Tanzania Craton is due to several geological events. These geological events include the intrusion of granites in the Archaean Tanzania Craton (3 Ga), subduction of ocean plate resulted to the formation of Usagaran belt (1.9 Ga), opening and closure of Mozambique Ocean, which resulted in the formation of the Mozambique belt between 700 – 800 Ma and the Pan African orogeny at 640 – 620 Ma, which is associated with the formation of Gondwana. It is believed that fragments from the Archaean Tanzania craton were re - metamorphosed during these events. The Handeni project (the focus of this thesis) is located in the northern portion of the eastern part of the Usagaran belt (1.9 Ga) comprising the eastern part of Archaean Tanzania Craton. The area is characterized by Proterozic rocks of basaltic composition. The documented 2.7 Ga rocks at the Kilindi Handeni Superterrane at the northern part of the Usagaran belt correlate well with 2.7 Ga of Nyanzian rocks of Archaean Tanzania craton. The Handeni project area is geologically dominated by metamorphosed and deformed units of quartzofeldspathic gneisses, migmatitic gneiss, garnet silicified rock, garnetiferous amphibolite, garnetiferous granulite, graphitic schist and hornblende pyroxenite. Intensive deformation features that were developed include folds (sheath folds, micro and macro scales), faults, shears and regional thrusts. This thesis focuses on identifying the protolith of the rocks, alteration minerals, and metamorphic assemblages in the project area in order to understand the timing of gold mineralization. Geological investigation of core, ore petrology and mineralogy, mineral composition by using JEOL microprobe analysis and XRF analysis of bulk rocks were utilized. All the analytical work was done at the Geology laboratory, Rhodes University. Petrographic analysis shows that the rocks sampled in the study area are characterized by alteration minerals such as calcite, dolomite and sericite. Sulphide minerals including chalcopyrite, pyrrhotite, pyrite, pentlandite and gersdorffite were identified. Gold mineralization is associated with disseminated sulphides in association with trace amounts of base metals. Four rock types were proposed as host rocks for the mineralization, namely garnet silicified rock with superimposed quartz veins, garnetiferous amphibolite, garnetiferous granulite and hornblende pyroxenite. Fold troughs, filled fractures associated with episodes of folding, quartz veins and shear zones are suggested as gold precipitation sites. The presence of high grade metamorphic rocks containing gold, intermediate to low grade assemblages with sulphides and associated hydrothermal alteration as well as a complex deformation history suggests that the Handeni mineralization took place over an extended time period stretching from a ductile to a brittle environment.]]> Thu 13 May 2021 05:05:57 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26567 Thu 13 May 2021 04:09:15 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26594 Thu 13 May 2021 02:50:03 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26597 Thu 13 May 2021 01:03:47 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:26590 Thu 13 May 2021 00:39:44 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:28722 Thu 01 Feb 2024 09:42:41 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:29390 Sat 04 Dec 2021 12:43:33 SAST ]]>