Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

[No abstract available] / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

The Silver Cup mine is about 10 miles east of Trout Lake in the Central Lardeau. From 1895 to 1915 it produced about 1.5 million oz. of silver and some lead, zinc, and gold. The problem of the paper is to study its geological setting and structural ore controls. Eastwood has shown that the mine is close to the axial plane of a major isoclinal anticline that is overturned to the southwest and plunging to the northwest. He has correlated the greenstones in the core of the anticline with the top of the Bunker Hill Group and has named the overlying black slates and phyllites Triune Formation. These two stratigraphic units were divided into three and four members respectively. The repetition of certain horizons and the trend of contacts indicates that the major anticline here has two apices separated by a tightly compressed syncline. Ninety five per cent of the production of the mine came from a zone that has a maximum length of 300 feet, a maximum width of 200 feet and has been stoped down to 1200 feet below its outcrop. Geological mapping shows that the ore is contained in openings of a structure that is a combination of a drag fold and a compressional bulge which is dipping with the host horizon to the northeast and raking steeply to the northwest. Host is the basal member of the Triune formation, a siliceous graphitic slate. Three other ore zones in the vicinity of the main zone have a similar lenticular shape and steep rake and are contained in the same member, but they are not all in the same structural position with respect to the two apices of the major anticline. These observations suggest that the mechanical properties of the host rock rather than a continuous structure such as a fault or a shear zone are responsible for the localization of ore. It is shown how the texture of the host rock, the thickness of the host member and the texture of the overlying rocks facilitate the formation of lens like openings if differential stresses are applied. Due to the steep rake of the structures, these stresses cannot be related to relative movement of outer layers towards the apices of the anticline. Their origin is not known but two hypotheses based on field evidence are offered. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

The major rock units within the area investigated are the Permian Chilliwack Group, the Upper Lower Jurassic - lower Middle Jurassic Cultus Formation, and the Upper Jurassic Lower Cretaceous Vedder Mountain Sediments. The Chilliwack rocks examined consist of four limestone units, a thick volcanic sequence, a conglomerate and argillites. The Cultus rocks consist of argillite, shale, graywacke and clastic limestone, The Vedder Mountain Sediments are graywackes, argillites and conglomerates. A tabular body of igneous rock and a schistose cherty rock are included in the sequence. The regional strike is to the north-east. Most of the rocks in the area are strongly fractured. The Cultus Formation is folded into a series of overturned isoclinal folds with axial planes striking north east and dipping south east. The strongly folded Chilliwack rocks are thrust over the Cultus rocks from the south and south east. The relationship of the Vedder Mountain sediments to the other major rock units is unknown. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

A study has been made of the martensitic transformations occurring in β-phase silver-cadmium and silver-zinc alloys. In silver-cadmium alloys the M(s) temperature was found to change from -44°C to -137°C as the cadmium content changed from 44.2 at. % Cd to 47.0 at. % Cd. Alloys of silver-zinc did not show any martensitic transformation; even on cooling to liquid helium temperature. The thermal martensite in Ag-45 at. % Cd alloy was found to have an orthorhombic structure of the 2H type. This was confirmed by X-ray diffraction and electron microscopy. A spontaneous martensite with a face centred cubic structure was found to occur along the thin edges of perforated specimens used for electron microscopy, because of the relaxation of volume constraints during thinning. In both Ag-45 at. % Cd and Ag-41 at.% Zn alloys a <111> slip direction was found. Also it was shown that Ag-45 at. % Cd alloy was elastically anisotropic, a characteristic very common to β-phase alloys. In both Ag-Cd and Ag-Zn alloys a face centred tetragonal structure could be formed on deforming the specimens by rolling or by tensile deformation. The structure changed to close-packed on severe deformation e.g. by filing. At lower Cd and Zn contents this close-packed structure was face centred cubic, whilst at higher alloy concentrations, this structure was close-packed hexagonal. Pseudo-elasticity was found to occur by stress-induced martensitic transformation. Maximum pseudo-elasticity occurred at temperatures just above A(f) and the actual amount of pseudo-elasticity was found to be dependent on the orientation of the tensile axis. The strain memory effect was studied by deforming specimens below A(f) and then heating. At temperatures below M(f), deformation of the martensite takes place and it is suggested that there is a change in the martensite structure, involving a change from thermal martensite to stress-induced martensite. The experimentally determined habit planes for thermal, stress-induced and deformation martensites were found to agree well with the values obtained using phenomenological theory assuming a {110}<11Ī0> microscopic shear. The 'elastic' elongations accompanying the transformation could be accounted for using the theory. A mechanism suggesting the course of the transformation was developed. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate

A number of synthetic routes to silver(II) fluorosulfate, Ag(SO₃F)₂, were systematically explored. The most suitable and versatile route was found to be the oxidation of silver metal by a solution of bisfluorosulfuryl peroxide, S₂0₆F₂, in fluorosulfuric acid, HSO₃F, according to: [chemical reaction] Additional methods which were found to be suitable involved the oxidation of a wide variety of silver(I) compounds such as Ag₂0 or AgSO₃F by S₂O₆F₂' or the insertion of S0₃ into AgF₂. Structural conclusions on Ag(S0₃F)₂ and the other compounds synthesized subsequently were based on the vibrational, electronic and electron spin resonance spectra, as well as on magnetic susceptibility measurements made between 300 and 77 K. Ag(S0₃F) ₂was found to be a true compound of divalent silver, with the Ag²⁺ ions in either square planar or tetragonally elongated octahedral environment. The only other example of a binary silver(II) compound is AgF₂. and characterized. The reactions of bromine(I) fluorosulfate with metallic silver and other silver(I) substrates resulted in a mixed valence complex Ag[sup I]Ag[sup II](SO₃F)₄ . Its potassium analogue K₂AgCSO₃F)₄, as well as two hexakisfluorosulfato- metallate (IV) complexes AgPt[sup= IV] (SO₃F)₆ , and AgSn[sup= IV] (SO₃F)₆, and the N-donor ligand complex [Ag(bipy)₂l (SO₃F)₂ (i-n which bipy = 2,2'-bipyridine) were also synthesized. The attempt to synthesize a silver(III) fluorosulfato complex by direct insertion of SO₃ into CsAgF₄ resulted in the fluorination of SO₃, to give S₂O₆F₂ and CsAg(SO₃F)₃. Finally, the solvolysi of Ag(SO₃F)₂ in trifluoromethylsulfuric acid, HSO₃CF₃, allowed its conversion into Ag(SO₃F₃). The principal synthetic route, the oxidation of metal by S₂O₆F₂ solutions in HSO₃F, was found to be useful in the preparation of Ru(SO₃F)₃. Ruthenium was also found to form a number of anionic derivatives with the metal in the +3 or +4 oxidation state, as in M[Ru(SO₃F)₄] with M = Cs⁺, ClO₂⁺ ; M₂[Ru(SO₃F)₆ with M = Cs⁺, K⁺; and Cs[Ru(SO₃F)₅]. Two different forms of Os(SO₃F)₃ were found. Initial oxidation of osmium metal with S₂O₆F₂ yielded the bright green a-Os(SO₃F)₃, which was converted to the light green β-form on long standing in S₂O₆F₂. / Science, Faculty of / Chemistry, Department of / Graduate

No description available.

No description available.

Inadequate access to safe drinking water is a critical challenge facing millions of people in third world countries. Ionic silver and copper both have proven biocidal capacities and are used in various water treatment applications such as cooling water and swimming pool disinfection. However, these methods of bacterial inactivation have not been expanded to include drinking water treatment due to the inherent health risks associated with consuming high concentrations of the metals which can accumulate in the systems, and therefore also the treated water. The goal of this research was to utilize copper and silver ions to inactivate bacteria in order to provide a method of drinking water treatment that does not require the use of toxic chemicals or large amounts of electricity, as under resourced communities do not have reliable access to these resources. This research also examined methods of removing or recovering residual metal from treated water. The ability to reduce the residual metal concentration not only allows the effluent to meet drinking water guidelines, it also allows for the concentration of metal used during disinfection to be significantly larger than used in previous research. By using a metal concentration that is one or two orders of magnitude higher than typical silver or copper ionization the disinfection is able to be carried out faster and to a fuller extent, all the while not increasing the risk to the consumer as the metal concentration can be decreased to within an acceptable range post disinfection. The lab scale, proof of concept methods used in this research show strong potential as prospective techniques to provide safe drinking water to people in third world nations. / Thesis / Master of Applied Science (MASc)

No description available.