A low energy gamma ray telescope, and the results of its observations are described. The telescope consisted of four sodium iodide crystals, each of 120 cm(2) area, occulted by lead discs. Charged particles are rejected using scintillation, anti-coincidence shields. The telescop…
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Pulsed nuclear magnetic resonance has been used for the investigation of YHx where x = 1.72, 1.81, 1.92 and 1.98, YD1.88, YH1.98 doped with 20, 50, 100, 200 and 915 ppm Gd, TiH1.74 doped with150, 500 and 104 ppm Mn and [Pd0.92y0.08]H0.51 • The Proton relaxation times T1 and T2 h…
89Y MAS NMR has been used to study the effects of substitution for Cu in YBa2(Cul_xMx)3O7 (M=V,Fe,Co,Ni,Zn,Al and Ga) and YBa2(Cu1,_yMy)4O8 (M=Zn and Fe). Substituted YBa2(Cu1_xMx)3O7 and YBa2(Cu1-yMy)4O8 samples have been characterized by means of XRD and A.C. susceptibility me…
The Electrochemical Polarisation, Photocurrent Spectroscopy and Extended X-ray Absorption Fine Structure (EXAFS) techniques have been used to study the passive film on pure iron and iron alloy samples containing up to 25% chromium. The material used in this work was prepared bot…
Au/PbSn joints are widely used in the microelectronics industry. Intermetallic formation in Au/60Sn-40wt. %Pb and in Au/62Sn-36Pb-2wt. %Ag systems has been studied in the temperature range 80°C-160°C using diffusion couples. Interdiffusion between Au films and 60Sn-40wt. %Pb sol…
The research described in this thesis is directed at advancing the state of the practice of the non-destructive gamma-ray assay of nuclear waste containers. A number of potentially accuracy-limiting issues were identified and addressed, resulting in new developments which were i…
Jets have been studied in high energy heavy ion collisions by measuring the angular correlation between particles at high transverse momentum. Differences in the yield and shape of the angular correlations as a function of system size give information on the medium produced in t…
This thesis is concerned with momentum anisotropy in strongly correlated electron systems, and explores its origin and its consequences through two contrasting projects. The first is a study of the temperature dependences of magnetotransport quantities in the normal state of the…
The research described in this thesis has focused on the properties of some nanometre scale systems mainly composed of gold. These systems have attracted a considerable amount of attention within the scientific community due to their vast range of applicability and their profoun…
Computational fluid dynamics (CFD) based Fire Field Modelling (FFM) codes offer powerful tools for fire safety engineers but their operation requires a high level of skill and an understanding of the mode of operation and limitations, in order to obtain meaningful results in com…
Virtual simulations of the behaviour of mechanical systems are of widespread use in academia and industry. Mechanical structures are often analysed using the finite element method, where deterministic models with one particular set of physical parameters are employed. However, t…
The focus of this thesis is the measurement of broadband fan noise, which due to reductions in tonal and jet noise, is now the dominant source at approach, and a major contributor at takeo. This thesis proposes three new in-duct measurement techniques for the characterisation an…
The dynamic modelling of one-dimensional jointed structures is relevant to many engineering applications, such as pipe systems and beam networks in constructions. Currently available techniques are undermined by inadequate ability to model the joints and other discontinuities du…
Theoretical models, such as TWINS, and microphone array measurements have been widely used to gain better understanding of rolling noise. However, the array measurements are often inconsistent with the TWINS predictions and give less prominence to the rail than the theoretical m…
This thesis contains original research into the propagation of sound in acoustically lined ducts with flow. The motivation for this work is the requirement to predict the sound attenuation of acoustic liners in the bypass duct of modern turbofan aeroengines. The liners provide t…
This thesis considers issues concerning the application of the wave finite element (WFE) method to the free and forced vibrations of one-dimensional waveguides. A short section of the waveguide is modelled using conventional finite element (FE) methods. A periodicity condition i…
This thesis describes the development of novel microstructured optical fibres (MOFs), namely holey optical fibres (HFs), based on a commercial highly nonlinear non-silica glass: By taking the advantages of the zero dispersion of the HFs at 1 μm and 1.55 μm, the SC studies are ca…
In this work we present an analysis of gas sensors based on correlation spectroscopy with a Fabry-Perot interferometer (FPI). In this technique the spectral FPI transmission fringe pattern is matched with ro-vibrational absorption lines. To produce the cross correlation principl…
In this thesis I investigate aspects of dispersion controlled high nonlinearity all silica holey fibre, including design, fabrication, sample applications, and modelling. The latest work has been focussed on controlled structural variation of holey fibres along their length to o…