Examination of Silica Sol-Gels and Aerogels Containing Silver Nanoparticles and 4-Mercaptobenzoic Acid Using Surface-Enhanced Raman Spectroscopy

Sol-gels and aero-gels containing silver nanoparticles have been investigated for use as substrates in surface-enhanced Raman spectroscopy (SERS). 4-Mercaptobenzoic acid (4-MBA) was chosen as the target molecule in this study, as it has been well-characterized using SERS. The orientation of the 4-MBA at different coverages in gels, and at differing concentrations of silver colloid, has not been well studied. For both base and acid-catalyzed sol-gels, xerogels, and aerogels, the concentration of 4-MBA was varied with a constant silver colloid concentration in the silica gels and the effects were measured with SERS. The effect of varying silver colloid concentration against a constant 4-MBA concentration was also investigated. The results of each process were compared

A cooking pot lit by fire

Recent research into the records of eclipses in the Chronicle of the English monk, Gervase of Canterbury, has indicated that an entry for the year 1187 C.E. may contain a description of solar prominences being visible during the total eclipse of that year. As such it is not only the earliest report of the phenomenon from England, but also reveals that a British Library manuscript contains the earliest surviving contemporary record of such an observation

The shear-driven Rayleigh problem for generalised Newtonian fluids

We consider a variant of the classical ‘Rayleigh problem’ (‘Stokes’s first problem’) in which a semi-infinite region of initially quiescent fluid is mobilised by a shear stress applied suddenly to its boundary. We show that self-similar solutions for the fluid velocity are available for any generalised Newtonian fluid, regardless of its constitutive law. We demonstrate how these solutions may be used to provide insight into some generic questions about the behaviour of unsteady, non-Newtonian boundary layers, and in particular the effect of shear thinning or thickening on the thickness of a boundary layer

Opportunities and barriers to sustainability innovation adoption in a UK water and sewerage company

Over the last twenty years, the concepts of sustainability and sustainable development have assumed political importance around the world, and have been largely embraced by governments and prominent international institutions. These concepts have been a means of tackling the challenges of population growth and environmental change. For the UK water sector, these concepts now represent a multitude of challenges. The confluence of climate change and population growth is reducing access to, and the availability of, water resources. The financial costs of inputs such as energy, chemicals, materials and cost of process by-products such as greenhouse gases, carbon, and waste services continue to rise. Government regulators are demanding an improvement in the quality of services, increasingly stringent conditions for emissions to water, air or land, catchment-specific management of the water environment, and the adoption of longterm planning horizons. The UK government has expectations that the water sector will play a role in the delivery of its targets for reducing energy consumption and carbon emissions. Society demands that WaSCs engage in high-level stakeholder consultations and employ long-term visions to guide their decision-making. Finally, WaSCs are increasingly expected to demonstrate and respond to local and global concerns (under the rubric of corporate responsibility) to further justify their value to society. Cont/d.EThOS - Electronic Theses Online ServiceGBUnited Kingdo