It is important to optimize glass compositions for their specific purpose but also for the efficiency of the production process, the manufacturing of glass. This will be beneficial economically and environmentally. Today many processes and glass compositions are already optimized, but due to more strict legislation on toxic elements and substances there must be changes in many glass compositions. One of these elements is antimony; the oxide is used as fining agent to obtain a bubble free glass within a reasonable process time. One aim with this thesis is to obtain a deeper understanding of the fining mechanism in 20R2O-10MO-70SiO2 (R=Na and/or K, M = Ca and/or Ba, Mg, Sr) glasses in order to minimise the amount of Sb2O3. Another intention is to study the structure of 20R2O-10CaO-70SiO2 (R = Na, K) with Cu2+ as probe ion and thus get a deeper knowledge of the surrounding glass matrix.  The optical basicity scale is used to determine the acid/base character of the different glass compositions.   Fining efficiency results showed a remarkable increase of the number of remaining bubbles when the glass contains either approximately equal amounts of Na and K or Ca and Ba, Mg or Sr. The much higher number of bubbles in the potassium containing glasses compared to the sodium containing is explained by the increase in viscosity, the increase in optical basicity and thus lower oxygen activity. The differences in the fining efficiency when altering alkaline earth ions cannot be explained by the optical basicity values, it seems to be a more complicated situation.   This thesis also reports maximum in Vickers hardness and packing density as well as minimum in glass transition temperature for the mixed alkali glasses. The mixed alkaline earth glasses do not exhibit any clear nonlinear behaviour. Raman spectroscopy measurements showed a variation in the network connectivity which has a clear relation to the optical basicity of the different glass compositions. The combination of UV-Vis-NIR and X-ray absorption spectroscopy measurements showed that the coordination sphere for Cu(II) is a tetragonal distorted octahedron with two elongated Cu-O bonds along the z axis. There were no trends in the degree of tetragonal distortion, thus it was about the same for all the investigated glass compositions. Cu(I) is found to be coordinated by two oxygen ligands in mainly linear coordination sphere, evidenced from X-ray absorption spectroscopy.

Cement-less and/cement-like geopolymer mortars were made with pulverised fuel ash (PFA) or ground granulated blast furnace slag (GGBS) activated by alkali with different alkali moduli (AM) and alkali dosage (AD). Once synthesised the samples were cured at 20°C and 70°C up to 28 days. The flexural and compressive strengths of these samples at early ages up to 28 days were tested conforming to BS EN196-1:2005. The electrical resistivity of these materials was monitored using a set of non-contacting electrodes to the age up to 7 days to characterise the geopolymerisation process from a physical phenomenon point of view. The effects of AD and AM on the early-age mechanical strengths and electrical resistivity of geopolymer materials were examined from the experimental results. The correlation between strength development and electrical resistivity was studied. The geopolymerisation process was characterised by a 5-stage model, based on electrical resistivity, analogue to hydration process of Portland cement. This research therefore proposes an alternative method for characterisation of geopolymerisation of geopolymers different from traditional methods based on chemistry. It is expected that such a physical phenomenon model will be better accepted by structural engineers for better promotion of usage of geopolymer composites, a type of low carbon and more sustainable binder-based materials, in construction.

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Call number: LD2668 .T4 1963 G99 / Master of Science

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.