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The study presented in this PhD thesis is related to exploration of the properties of graphitic materials within the frame-work of ab initio methods. Structural and dynamical properties of graphitic materials are evaluated using the ab initio pseudopotential method. In graphitic materials, properties are obtained by incorporating Van der Waals interactions together with the generalized gradient approximation to density functional theory. These Van der Waals interactions improve the structural and dynamics of graphitic systems. In order to study the dynamical properties, the finite displacement method has been used to construct the dynamical matrix and force constant matrix. Phonon dispersions are investigated by the direct force constant matrix method in supercells. In this approach, force constants are assumed to be zero beyond a certain limit. Phonon frequencies are calculated from the force constant matrix. The dispersion relations and the Brillouin zone integrated density of states are also investigated. The significance of phonon dispersion has been studied to in various regions. Results are compared with dispersion corrected scheme and without dispersion corrected schemes to understand the importance of dispersion correction. Conclusions are also drawn on the applicability of theoretical approximations used. Further, ab initio results are also compared with the available data from experimental studies. The binding energies and electronic band gaps of exo-hydrogenated carbon nanotubes are determined to investigate the stability and band gap opening using density functional theory. The vibrational density of states for hydrogenated carbon nanotubes has been calculated to confirm the C-H stretching mode due to sp3 hybridization. The thermodynamical stability of hydrogenated carbon nanotubes has been explored in the chemisorption limit. Statistical physics and density functional theory calculations have been used to predict hydrogen release temperatures at standard pressure in zigzag and armchair carbon nanotubes.

This thesis investigates the development of a vapour sensor that is useful in fields such as environmental protection, or healthcare. A summary review of vapour sensing techniques is given, leading to the choice of exploiting a simple, low cost, high-resolution mass sensing technique-Quartz Crystal Microbalance (QCM) to fabricate a lipid based vapour sensor. Both hydrophilic and hydrophobic vapours have been introduced in the sensing experiment. Three types of lipids based sensors, which were 1, 2-dilauroyl-sn-glycero-3-phosphocholine (DLPC), 1, 2-dioctadecanoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol and their mixtures, were fabricated on AT cut quartz crystal based substrates by spin coating. Atomic Force Microscopy (AFM) was used for topography analysis; QCM was used for quantitative analysis. Film thickness data suggests that a bilayer DLPC is 4.3 nm and a bilayer DSPC is 5.8 nm thick. The average film thickness is approximately proportional to the coating concentration with a constant of proportionality of 4.3 nm/mM and 5.8 nm/mM for DLPC and DSPC, respectively. The results from the AFM and QCM trials have led to the development of a controllable process for the fabrication of a repeatable amount of lipid membrane based vapour sensors. The response of each film when exposed to ethanol, methanol, toluene and cyclohexane vapours was recorded. The results show that hydrophilic compounds could be recognised efficiently by lipids having shorter alkyl chains. Frequency changes caused by adsorption of test vapours could be enhanced when cholesterol was co-immobilised in the lipid layer. The best sensing behaviour (that is, excellent response, reversibility and negligible baseline drift) and sensitivity was achieved in a sensor coated with DLPC/DSPC/cholesterol mixed film (50 mg/ml DLPC/DSPC/cholesterol-1:1:8 in volume ratio). The limit of detection of this sensor is 400 ppm to ethanol, 800 ppm to methanol, 1300 ppm to toluene and 2300 ppm to cyclohexane, separately.

The provision of a safe and economic rock support system is of primary importance for any excavation programme. If the excavation is to be developed by explosives, then the effect of blast forces on the performance of the rock support system must be considered. A review of current literature has highlighted a general lack of information regarding rock anchorage performance under blast loading. With this in mind, a full scale field test programme was undertaken to study the effect of close proximity blasting on resin bonded rock bolts, during the construction of the Pen y Clip Tunnel in North Wales together with a re-analysis of data from a previous study at the nearby Penmaenbach Tunnel. In both cases, accelerometers were used to monitor vibration and hydraulic load cells recorded the changes in rock bolt load during production face blasting. For the Pen y Clip trials, an additional monitoring system was developed which incorporated load cells positioned along the length of specially made experimental rock bolts. Further trials were conducted at an Edinburgh City Centre site to assess the likelihood of damage to temporary, cement grouted rock anchorages whose fixed anchors were positioned as close as 5m from nearby tunnel blasting. These trials involved the measurement of vibrations, both on the anchor head and down specially constructed boreholes, together with lift off load testing. Analysis consisted of the time and frequency domain examination of the signals, recorded on FM magnetic tape, from the three sets of field trials. Resin bonded rock bolts installed in microdiorite and rhyolite were found to be highly resilient to blasting, even those positioned down to lm from full face tunnel blasting. Temporary anchorages in mudstone were more susceptible to blasting but damage could be limited by monitoring of vibrations and careful control of blast parameters. The frequency response of the anchor head was found to be dependent on the characteristics of the anchorage and the nature of the environment in which it was installed. This raises the possibility that the analysis of spectral responses could form the basis of a technique for the non destructive testing of rock anchorages.

The Vacuum Lug Closure system, or VLC, is found on many widely available products such as jam, sauces and pickles. The closure has many useful advantages over other closure systems, and it is popular with both manufacturers and consumers. However, there are large groups ofpeople that have great difficulty opening products packaged in jars with vacuum lug caps. The goal of this project is to understand both the way in which consumers interact with the closure, and also how the closure system works. The torque that users can apply to ajar lid was measured using a torque sensor embedded in a modified jar. This was then compared to a calcula~ed torque derived from grip measurements. This second type oftest can be used to predict openability for any kind of closure by utilising simple and quick tests and mathematically adapting strength test data. By eliminating the need to perform more extensive tests, costs are kept to a minimum whilst ensuring that the results are still relevant to the problem. The results from both tests were compared with the measured forces required to open examples ofconsumer packaging found on sale. The results from both tests agree reasonably well, but more data is required regarding the interaction between human skin and packaging materials. However the current required opening torques were found to be far too high for many users. It is suggested that a limit of 1Nm torque should be used for future packaging designs to allow over 97% ofthe UK population to openjars. The optimal diameter ofjar lid was found to be 73 mm.

Soft nanotechnology requires the development and understanding of smart polymeric systems that respond to small changes in the surrounding environment. This thesis reports on the structure and dynamics in poly(methacn"lic acid) (PMAA) hydrogels and hyperbranched poly(N-isopropyl acrylamide) (HB-PNIPAM) in response to physical and chemical stimuli. Fluorescence correlation spectroscopy (FCS) has been utilized to study the diffusion of single dextran molecules labelled with fluorescein isothiocyanate within a PMAA hydrogel. Diffusion in pure water shows a temperature dependence described by Zimm dynamics, whereas the diffusion coefficient decreases with temperature in the hydrogel for which a model has been developed. Diffusion in PMAA hydrogel has revealed the mesh size dependence on temperature. The effect of pH and salt on the diffusion in PMAA hydrogel has also been considered. Introducing magnetic nanoparticles to hydrogels forms ferrogels the mesh of which is controlled by applied magnetic fields. The swelling, diffusion and release in PMAA ferro gel has been found to follow the same scaling theory developed in this work. Small angle neutron scattering (SANS) has revealed the structural behaviour of HB-PNIPAM as a function of temperature compared to its linear counterpart. These experiments have shown that water is a good solvent for HB-PNIPAM at low temperatures, while increasing the temperature leads to a gradual collapse of these polymers until they form spherical particles with sharp boundaries of the order of 24-40 nm in diameter, depending on the branching degree. This indicates that HB-PNIPAM shows no entanglements either as a function of temperature or branching degree. In contrast, linear PNIPAM showed a network-like behaviour above its collapsing temperature. Neutron spin echo experiments on HB-PNIPAM are described well by the Rouse model for unentangled chains and the self-diffusion of HB-PNIPAl\I by FCS follows Zimm behaviour, which is in agreement with SANS results. These studies have given a better understanding of the nanostructure and dynamics in the investigated polymeric systems, showing their usefulness as delivery systems for many biological and medical applications.

Computational design of mechanical components is an iterative process that involves multiple stress analysis runs; this can be time consuming and expensive. Significant improvements in the efficiency of this process can be made by increasing the level of interactivity. One approach is through real-time re-analysis of models with continuously updating geometry. In this work the boundary element method is used to realise this vision. Three primary areas need to be considered to accelerate the re-solution of boundary element problems. These are re-meshing the model, updating the boundary element system of equations and re-solution of the system. Once the initial model has been constructed and solved, the user may apply geometric perturbations to parts of the model. A new re-meshing algorithm accommodates these changes in geometry whilst retaining as much of the existing mesh as possible. This allows the majority of the previous boundary element system of equations to be re-used for the new analysis. Efficiency is achieved during re-integration by applying a reusable intrinsic sample point (RISP) integration scheme with a 64-bit single precision code. Parts of the boundary element system that have not been updated are retained by the re-analysis and integrals that multiply zero boundary conditions are suppressed. For models with fewer than 10,000 degrees of freedom, the re-integration algorithm performs up to five times faster than a standard integration scheme with less than 0.15% reduction in the L_2-norm accuracy of the solution vector. The method parallelises easily and an additional six times speed-up can be achieved on eight processors over the serial implementation. The performance of a range of direct, iterative and reduction based linear solvers have been compared for solving the boundary element system with the iterative generalised minimal residual (GMRES) solver providing the fastest convergence rate and the most accurate result. Further time savings are made by preconditioning the updated system with the LU decomposition of the original system. Using these techniques, near real-time analysis can be achieved for three-dimensional simulations; for two-dimensional models such real-time performance has already been demonstrated.

Closely sized cuts of ballotini and sand were prepared and mixed in a Y-cone blender, adding varying amounts of water, in order that the effect of the moisture content on the equilibrium mixture quality might be studied. The moisture additions caused the mixtures to exhibit an increasingly cohesive behaviour, and marked improvement in the equilibrium mixture quality, which occurred at a well defined though difficult to predict value of the moisture content. Two forms of water retention were examined, (adsorbed layers and liquid bridges) and the value of the interparticulate force calculated, as a function of humidity, temperature. pressure, solid nature and surface roughness. Two datum values of the humidity were defined: a) A minimum humidity at which adsorbed layer interaction becomes important. b) A critical humidity at which liquid bridges first appear. These two datum values are related to the solid nature, surface roughness, temperature and pressure. Statistical analysis of the mixing process is made for a binary mixture taking aggregation into account, and formulae for the segregated and random variances are derived. These become a function of the aggregation pattern, and it is shown that as aggregation increases both the random and the segregated variances should decrease, statistically confirming the experimentally known fact that cohesive powders are not segregation prone. A simple pattern of aggregation is used to illustrate the above concepts and the validity of the statistical approach confirmed by a computer simulation of sampling from such a mixture, the results of which were in good agreement with the calculated values. Computer routines for the calculation of interparticulate forces and random and segregated standard deviations, and the simulation program are included.

Governments and businesses around the world have invested billions of pounds in nanotechnology research and development, and more than a thousand consumer products which manufacturers claim to involve nanotechnology are currently on the market. As such, the applications from this emerging field of science and technology have the potential for great impact on individuals and society, making it a recurring subject of news reporting worldwide. Scholars say mainstream news media are the primary places in which citizens learn about science and technology, therefore creating opportunities for democratic debate about these topics. This thesis explores the ways in which nanotechnology is reported in order to understand how journalists strive to make sense of it for their audiences. It analyses 759 articles from two opinion-leading newspapers – The Guardian and The New York Times – in order to address the following research questions: How do journalists frame nanotechnology for their audiences? How do the characteristic features of the framing processes change over time? And to what extent does the reporting open opportunities for meaningful, democratic discussion around nanotechnology? To answer these questions, the research evaluates literature around the reporting of science and technology, in particular nanotechnology. Using quantitative and qualitative approaches to framing, this thesis finds the coverage is overwhelmingly positive in its treatment of nanotechnology, suggesting it closely aligns with the business and government interests. Additionally, claims about the potential benefits of nanotechnology are prioritised over risk claims in news articles, with the most common risk and benefit claims being those that are more likely to materialise decades into the future, if ever. Altogether, in failing to discuss applications and potential risks of nanotechnology without drawing on popular culture references limits the opportunity for meaningful, democratic discussion and debate.

A common goal for designers is to deliver an intentional message from the sender to the intended receivers via design. !e design can be constructed to be a crystal-clear and interesting model that viewers can easily and immediately understand. However, some designs are intricate, complex, and layered in detail, and these require more e"ort on the part of the viewer if they are to understand the design messages. During the design process, designers pass through several stages that a"ect the design outcome. One of these key stages is the colouring process. Colour has the power to make or break the design intention. In addition, colour can either add complexity to the design by the use of di"erent colour contrasts, or help simplify a complex design form. !is research investigates the e"ect of colour combinations on simple and complex design appearance, with regard to the e"ects of contrast when colours are juxtaposed in a design. !e aim of the research is to identify which colour contrast a"ects the simplicity and complexity of a design’s appearance. !e research demonstrates how design form could be evaluated di"erently in terms of the use of di"erent colour combinations. !e research uses applied experimental methods to analyze participant responses to colour combinations. It reveals the result of the study by describing the signs of simple and complex colour combinations and the e"ect of colour on di"erent designs. !e research also proposes methods for increasing or decreasing the level of complexity of a design solution by using di"erent colour combinations with their associated e"ects on the diversity of colour contrast. All of this information is used to create a design tool which will help designers and students to make colour choices which are more suited to the design solution.