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Abstract: Three areas of investigation regarding a novel class of potential anti-cancer therapeutics, triple helicate dinuclear compounds known as ‘cylinders’, have been addressed in this work - the synthesis of a ruthenium-based cylinder, determining the cellular localisation of the cylinders, also determining the cellular e ↵ ects of the cylinders. An improved protocol for the synthesis of a ruthenium cylinder has been developed, utilising microwave synthesis as opposed to previously used reflux techniques. Whilst not leading to an increase in yield, the synthesis is now much shorter as there is no need for the synthesis of intermediate compound Ru(DMSO) 4 Cl 2 , and the use of Sephadex C-25 as a solid phase for column chromatography has led to a shorter purification protocol. First attempts at determining the cellular localisation of the fluorescent ruthenium cylin- der have been undertaken, with confocal microscopy showing observable fluorescence within MDA-MB-231 breast cancer cells, but not within SKOV-3 ovarian cancer cells, suggesting some level of preferential uptake or metabolism of cylinder between cell lines. Co-localisation exper- iments with Hoechst nuclear stains appear to show the reduction in mean fluorescence following treatment with iron cylinder, suggesting localisation of the cylinder within cell nuclei. Using the I-18 beamline at Diamond Light Source, synchrotron radiation has been used to further investigate the cellular localisation of the cylinders. A sample preparation route of growing cells on silicon nitride windows has been developed, and allowed for the imaging of iron and nickel cylinders within SKOV-3 cells. High levels of iron are found near the cell membrane, corresponding to areas of high calcium concentration, whereas nickel is found more uniformly spread throughout the cell. XANES spectra of these areas show that the iron is in an environment closer to that of the ferric iron found in ferrihydrite as opposed to the ferrous iron found within the cylinder. The cellular e ↵ ects of cylinder treatment have also been imaged, with the main observation being that the motility of cells is compromised by cylinder treatment. The iron cylinder causes the production of nitric oxide within MDA-MB-231 cells. Images taken as part of control experiments showed low levels of fluorescence within MDA-MB-231 cells, suggesting that this cell line does produce endogenous nitric oxide, something that has been a subject of debate within the literature

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Abstract: Tuffisite veins are glass-filled fractures formed when magma fragments during degassing within the conduit. These veins form transient channels through which exsolved gases can escape from magma. The purpose of this study is to determine the extent to which chemical heterogeneity within the melt results from gas transport, and assess how this can be used to study magma degassing. Two tuffisite veins from contrasting rhyolitic eruptions at Torfajökull (Iceland) and Chaitén (Chile) were studied in detail. The tuffisite vein from Torfajökull is from a shallow dissected conduit (∼70 ka) that fed a degassed lava flow, while the sample from Chaitén was a bomb ejected during the waning phases of Plinian activity in May 2008. The results of detailed in situ chemical analyses (synchrotron XRF, FTIR, LA-ICP-MS) show that in both veins larger vesiculated fragments are enriched in volatile elements (Torfajökull: H, Li, Cl; Chaitén: Li, Cl, Cu, Zn, As, Sn, Sb) compared to the host, while the surrounding smaller particles are depleted in the Torfajökull vein (Li, Cl, Zn, Br, Rb, Pb), but enriched in the Chaitén vein (K, Cu, Zn, As, Mo, Sb, Pb). The lifespans of both veins and the fluxes of gas and particles through them can be estimated using diffusion profiles and enrichment factors. The Torfajökull vein had a longer lifespan (∼a day) and low particle velocities (∼cm/s), while the Chaitén vein was shorter lived (<1 h) with a high gas velocity (∼m/s). These differences are consistent with the contrasting eruption mechanisms (effusive vs. explosive). The amount of magma that degassed through the Chaitén vein is more than ten times the volume of the vein itself, requiring the vein to tap into pre-exsolved gas pockets. This study highlights that tuffisite veins are highly efficient gas pathways and thereby impart chemical diversity in volatile elements on the melt.

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Abstract: Atmospheric pitting corrosion of stainless steel was studied to determine pit growth mechanisms and kinetics. Inkjet printing of chloride was used to investigate the growth of atmospheric corrosion pits. It has been shown that the pit size increases with increasing chloride deposition density, as well as increases with increasing deposit diameter.

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Abstract: Red mud leachate (pH 13) collected from Ajka, Hungary is neutralized to < pH 10 by HCl, gypsum, or seawater addition. During acid neutralization >99% Al is removed from solution during the formation of an amorphous boehmite-like precipitate and dawsonite. Minor amounts of As (24%) are also removed from solution via surface adsorption of As onto the Al oxyhydroxides. Gypsum addition to red mud leachate results in the precipitation of calcite, both in experiments and in field samples recovered from rivers treated with gypsum after the October 2010 red mud spill. Calcite precipitation results in 86% Al and 81% As removal from solution, and both are nonexchangeable with 0.1 mol L–1 phosphate solution. Contrary to As associated with neoformed Al oxyhydroxides, EXAFS analysis of the calcite precipitates revealed only isolated arsenate tetrahedra with no evidence for surface adsorption or incorporation into the calcite structure, possibly as a result of very rapid As scavenging by the calcite precipitate. Seawater neutralization also resulted in carbonate precipitation, with >99% Al and 74% As removed from solution during the formation of a poorly ordered hydrotalcite phase and via surface adsorption to the neoformed precipitates, respectively. Half the bound As could be remobilized by phosphate addition, indicating that As was weakly bound, possibly in the hydrotalcite interlayer. Only 5–16% V was removed from solution during neutralization, demonstrating a lack of interaction with any of the neoformed precipitates. High V concentrations are therefore likely to be an intractable problem during the treatment of red mud leachates.