https://commons.ufh.ac.za/vital/access/manager/Index ${session.getAttribute("locale")} 5 https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9959 Wed 12 May 2021 23:25:48 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:8313 Wed 12 May 2021 23:22:29 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:931 Wed 12 May 2021 23:08:04 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10364 45 μM were found in February and April 2011 at the 5 m deep hole at 3.4 km upstream. Negative correlations between dissolved oxygen and NH4+ during November 2010, February 2011, April 2011 and July 2011 (r = -0.68; -0.67; -0.63; -0.96) indicated that remineralisation of organic matter had occurred. Soluble reactive phosphorus (SRP) followed a similar trend to the NH4+ and was generally below 1 μM in the water column for most months, and had peaks at 1.0 km and 3.4 km in the bottom water. The abundance of submerged macrophytes and macroalgae below the N2 bridge were mostly influenced by mouth state and river inflow. During the closed phase the dominant macroalga Cladophora glomerata had an area cover ranging from 3000 to 6000 m2 while Zostera capensis and Ruppia cirrhosa covered an area of 2000 to 3500 m2 and 1500 to 2900 m2, respectively. After an artificial breach in February 2011, water drained out of the estuary leaving the alga stranded on the marshes and as the flood tide entered the macroalga was once again redistributed in the lower reaches. The alga utilised the available nutrients in the water column and expanded its area cover from 35000 m2 in February 2011 to 64000 m2 in March 2011. However, after the floods in June 2011, Cladophora glomerata had been washed out of the system while the submerged macrophytes responded positively extending their area cover. By comparing the artificial breach with the natural breach, and the effect on the estuary, an important observation was highlighted. Increasing the current allocated ecological reserve, and using a larger volume of water to breach the mouth artificially, would result in better scouring of sediment and associated organic matter out of the estuary. This would enable better oxygenation of the water column, reduce remineralisation and minimise algal blooms.]]> Wed 12 May 2021 23:00:04 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:1407 Wed 12 May 2021 22:43:54 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4286 Wed 12 May 2021 22:28:40 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10557 Wed 12 May 2021 22:24:09 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:3665 Wed 12 May 2021 20:37:09 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10665 Wed 12 May 2021 20:35:59 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4557 Wed 12 May 2021 20:17:39 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10596 Wed 12 May 2021 20:13:21 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5586 Wed 12 May 2021 20:11:35 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10356 Wed 12 May 2021 20:06:24 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9827 Wed 12 May 2021 19:51:53 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5609 Wed 12 May 2021 19:43:43 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:2447 Wed 12 May 2021 19:37:40 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9579 Wed 12 May 2021 18:45:00 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5610 Wed 12 May 2021 18:41:58 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:1840 Wed 12 May 2021 18:39:28 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4741 Wed 12 May 2021 18:16:27 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5621 Wed 12 May 2021 18:05:21 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9829 Wed 12 May 2021 18:04:32 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10510 Wed 12 May 2021 17:48:52 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10354 Wed 12 May 2021 17:32:11 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:3888 Wed 12 May 2021 17:29:53 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4562 Co(II) > Ni(II). The Schiff-base derivatives were prepared from the ligands and para-methoxysalicylaldehyde and their Cu(II) complexes were synthesized in order to determine their biological activity. The Schiff-base ligands were found to be less active than their parent ligands. The Cu(II) complexes are not soluble in water, DMSO or DMF, as a result and could not be evaluated for their biological activity. Based on the good results from the antimicrobial evaluation, the antiplasmodial activity of some of the Co(II), Ni(II) and Cu(II) complexes of the thiomethylated ligands against Plasmodium falciparum (FCR-3) was determined. At 50 μM concentration level, the Cu(II) complexes show activity equal or better than the prophylactic chloroquine. The Cu(II) complexes with the methoxy-substituted demonstrated exceptional activity but their Co(II) and Ni(II) analogues did not show any activity. The cytotoxicity of the active Cu(II) complexes at 50 μM concentration was determined against the breast cancer cell line (MDA-MB-231). The compounds destroyed the cancer cell in the range of 28–40%, thus showing their preferred activity against the parasitic cell instead of the cancer cell. The selectivity demonstrated by these compounds have shown them to be potential antimalarial agents and this could be further investigated.]]> Wed 12 May 2021 17:24:20 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9571 Wed 12 May 2021 17:16:39 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10357 Wed 12 May 2021 17:15:55 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:3337 Wed 12 May 2021 17:08:03 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:11444 Wed 12 May 2021 16:42:36 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4281 Ni²⁺ > Zn²⁺ > Cd²⁺> Co²⁺ was achieved as a function of pH. At pH 1.65 the extracted copper, from a synthetic mixture of the base metals reached 90.13(±0.90)%, and through a two-step extraction process 98.22(±0.29)% copper was recovered with negligible nickel and cobalt impurities. Stripping of the copper from the loaded organic phase using TraceSelect sulphuric acid at pH 0.35 yielded 96.60(±0.44)% of the loaded quantity after the second stage of stripping. The separation of Ni²⁺ from the borderline and hard acids; Co²⁺, Cu²⁺, Zn²⁺, Fe2²⁺, Fe²⁺, Mn²⁺, Mg2²⁺ and Ca²⁺ at a pH range of 0.5-3.5 with OPIM and DNNSA was acvieved to the tune of a ΔpH½≈ 1.6 with respect to cobalt from a sulfate and sulfate/chloride media. A three-stage counter-current extraction of Ni²⁺, at the optimized pH of 1.89, from a synthetic mixture of Ni²⁺, Co²⁺ and Cu²⁺, yielded 99.01(±1.79)%. The total co-extracted Cu²⁺ was 48.72(±0.24)% of the original quantity in the mixture, and it was 19.85(±0.28%) for Co²⁺. The co-extracted Cu²⁺ was scrubbed off from the loaded organic phase at pH≈8.5 by using an ammonium buffer, while co-extracted Co²⁺ was selectively and quantitatively stripped with H₂SO₄ at pH 1.64. The total recovery of Ni²⁺ by stripping at pH 0.32 was 94.05(±1.70)%. In the solid-liquid system, Ni²⁺ was separated from Co²⁺, Cu²⁺, and Fe²⁺ with the microspherical resins funtionalised with 2,2′-pyridylimidazole by a separation factor (β) in the range 22-45. Electrospun nanofibers as sorbents yielded high sorption capacity in the range of 0.97 - 1.45 mmol.g⁻¹ for the same metals ions. Thus, 1-octylimidazole-2-aldoxime (OIMOX), and1-octyl-2-(2′-pyridyl)imidazole (OPIM) can be effectively utilized alongside DNNSA as a co-extractant in the separation of Cu²⁺ and Ni²⁺ respectively from base metals in acidic sulfate medium in a solvent extraction process, and the latter as a selective ligand in the solid-liquid separation of Ni²⁺ from Co²⁺, Cu²⁺, and Fe²⁺.]]> Wed 12 May 2021 16:26:16 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10064 Wed 12 May 2021 16:18:09 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5397 Wed 12 May 2021 16:16:19 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9815 Wed 12 May 2021 16:12:17 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:1888 Wed 12 May 2021 16:03:14 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:6023 Wed 12 May 2021 15:59:29 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:21069 Wed 12 May 2021 15:55:54 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:6052 Wed 12 May 2021 15:55:13 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4439 Wed 12 May 2021 15:44:41 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:1891 Wed 12 May 2021 15:44:06 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:3411 Thu 13 May 2021 13:55:25 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:2166 Thu 13 May 2021 10:12:11 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:3616 Thu 13 May 2021 09:56:44 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9280 Thu 13 May 2021 08:14:15 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:21137 Thu 13 May 2021 07:18:53 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10641 Thu 13 May 2021 07:16:53 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4278 Thu 13 May 2021 07:14:17 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9584 Thu 13 May 2021 07:08:26 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10672 Thu 13 May 2021 07:02:31 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5198 Thu 13 May 2021 06:45:57 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:21071 Thu 13 May 2021 06:31:44 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4728 Thu 13 May 2021 06:21:29 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:2517 Thu 13 May 2021 06:20:31 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4729 Thu 13 May 2021 05:45:42 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5587 Thu 13 May 2021 05:39:45 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:2752 Thu 13 May 2021 05:33:47 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4555 Thu 13 May 2021 05:23:51 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5504 Thu 13 May 2021 05:20:46 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4060 Thu 13 May 2021 05:15:09 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10066 Thu 13 May 2021 05:10:26 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:1314 Thu 13 May 2021 04:59:12 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:3555 Thu 13 May 2021 04:42:13 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9826 Thu 13 May 2021 04:41:41 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5585 Thu 13 May 2021 04:38:58 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4733 Thu 13 May 2021 04:22:25 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4915 2 wt %) crystallise Fe-Ti oxides early whereas low H2O magmas (< 1 wt %) crystallise oxides late. Early pulses of H2O-poor magma crystallise a sequence of plag+cpx+Fe-Ti oxide (±ol). Later pulses of H2Orich magma subsequently intrude the partially crystallised cumulate sequence incorporating and consuming previously crystallised silicates with subsequent early crystallisation of Ti-magnetite and formation of ore layers. H2O-rich magmas likely have suspended Ti-magnetite microphenocrysts as well, which crystallise at depth in the plumbing system. This model can account for the various characteristic features of the Fe-Ti oxide ore layers at the Panzhihua intrusion as well as other Fe-Ti oxide ore bearing intrusions in the region.]]> Thu 13 May 2021 03:57:26 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4277 Thu 13 May 2021 03:57:19 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10555 Thu 13 May 2021 03:51:44 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5588 Thu 13 May 2021 03:05:37 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:1400 Thu 13 May 2021 02:49:32 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:1887 Thu 13 May 2021 02:38:21 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:8245 Thu 13 May 2021 02:17:30 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9684 Thu 13 May 2021 02:09:30 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:16151 Thu 13 May 2021 02:00:46 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:9821 Thu 13 May 2021 01:50:23 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:1033 Thu 13 May 2021 01:50:13 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:3508 Thu 13 May 2021 01:44:54 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5182 Thu 13 May 2021 01:18:01 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5396 Thu 13 May 2021 01:11:32 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:5386 Thu 13 May 2021 01:05:30 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:10655 2 km) and Congo (>200 m) are linked to interactions between the lithosphere and mantle geodynamics, and how these processes likely affected global climate changes.]]> Thu 13 May 2021 00:52:18 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:3887 Thu 13 May 2021 00:48:55 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:6024 Thu 13 May 2021 00:27:55 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:4282 Thu 13 May 2021 00:27:23 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:2736 Thu 13 May 2021 00:12:18 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:1836 Thu 06 Jul 2023 12:06:44 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:2894 Mon 15 Aug 2022 13:28:48 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:2531 Mon 10 Oct 2022 14:29:46 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:2530 Mon 10 Oct 2022 14:29:19 SAST ]]>