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A number of complexes of the first row transition metal halides and pseudohalides in the 2 oxidation state with pyridine and substituted pyridines have been prepared. These have taken the form ML4X2 (where M= Ni, L =pyridine, 3-methyIpyridine, 4-methyl-pyridine, 3,5-lutidine, 4-vinylpyridine, 3-chloropyridine and isoquinoline, X= Cl, Br, I, NCS, NCO; Fe, Co, L-4-vinyl- pyridine, X= Cl, Br, I, NCS, NCO) and ML2X2 (where M=Ni, L = pyridine 3-methylpyridine, 4-methylpyridine, 3,5-lutidine, 4-vinylpyridine, 3-bromopyridine, X=Cl, Br, NCS, N3; M=Mn, Fe, Co, Cu, Zn, L= 4-vinylpyridine, 2-vinylpyridine, X= Cl, Br, I, NCS, NCO, N3). These complexes have been examined using techniques of i. r. , far i. r. and Raman spectroscopy, U. V. and visible spectroscopy and magnetochemistry in an attempt to correlate the structures with the spectral measurements. The nickel(Il) complexes were treated in greater detail since an attempt to relate changes in visible spectral parameters with donor properties of the ligands was made; and to this end values of the ligand-field splitting parameters in the xy plane and along the z axis, i. e. DqXY and Dqz were evaluated from the splitting of the spin-allowed bands observable in the electronic spectrum. A linear relationship was found between the spectral parameters in the xy plane and along the z axis, and this was interpreted as meaning that a change in length of the bonds in the xy plane would effect the length of the bonds along the z axis. The lengths of the bonds would in turn be related to the donor properties of the ligands. A previous report that the vinyl group of 2-vinylpyridine will co-ordinate to copper (Il) has not been confirmed.

This work is concerned with the measurement of internal friction peaks in niobium at low temperatures and low frequencies, the analysis of the data from the peaks and its theoretical interpretation. A sensitive automatic apparatus using a novel variable energy supply technique, has been constructed, together with a continuous flow cryostat, A technique for analysing internal friction data by the application of constrained optimisation methods on a digital computer is described. The beta peak occuring in niobium at about 200 K at 1 Hz, is interpreted as a possible hydrogen Schoek peak. The Arhenius plot of the known values of the beta peak parameters from the present work and all other available sources, is examined in detail, and it is concluded that the plot is either non linear or exhibits a slope change. An explanation for this anomalous behaviour is advanced.

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Electronically conducting polymers based on functionalised thiophenes and pyrroles have continued to stimulate academic interest as well as starting to be employed in practical applications and uses. This thesis describes studies of the electronic properties of mixed thiophene-pyrrole polymers (based on custom synthesised mixed monomer precursors) and polymers electrodeposited from commercially available monomers, pyrrole and 3,4-ethylenedioxythiophene, in respect to energy storage applications including batteries and ion selective membranes. In such applications the movement of ion and solvent through the polymer film during oxidation and reduction cycles is critical to application and function, e.g. charging rate, metal ion permeability or adhesion stability. Recently the unexpected behaviour of polypyrrole in choline chloride based ionic liquids has been described. These liquids are especially attractive because of their unique solubility profiles, high stability, low volatility and low toxicity. This thesis describes the electrochemical characterisation, DC capacitance behaviour and ion/solvent transport properties of conducting polymers using a range of electrochemical methodologies in combination with acoustic impedance electrochemical quartz crystal microbalance techniques (EQCM) and X-Ray Photo-electron Spectroscopy (XPS). The behaviour of several mixed thiophene-pyrrole films, polypyrrole and poly 3,4-ethylenedioxythiophene in different electrolyte media; deep eutectic solvents (DESs), conventional organic solvents and aqueous media are contrasted in this thesis. PEDOT and one of the mixed thiophene-pyrrole polymers (poly 2-(thiophene-2-yl)-1H pyrrole) gave the highest DC capacitances of the polymers investigated, with high values observed in both choline chloride based (Type III) and zinc based (Type IV) DESs. The ion dynamics of the polymers p-doping in the DESs, observed to fit gravimetric data recorded, was able to show a marked difference in the ion transfers between DES types and a conventional organic solvent, acetonitrile. Both polymers in acetonitrile and the zinc based DES (ZnCl2 / EG) satisfied the electro-neutrality condition through dominance of anion transfers. Whereas, polymers in the choline chloride based DES (Ethaline) satisfied the electro-neutrality condition through dominance of choline cation transfers (in the opposite direction to anion transfers). This research involved work towards the development of a new class of rechargeable batteries based on a Zinc-Polymer system incorporating a novel, inexpensive, environmentally sustainable solvent. This work is necessitated by the problems associated with petrol and diesel powered vehicles and the limitations of batteries available for electric vehicles.

Coal tars are complex mixtures of inorganic and organic compounds, which are dominated by PAHs and were produced as a by-product of the former manufactured gas industry. Forensic analysis of coal tar samples was carried out using two dimensional gas chromatography coupled with time-of-flight mass spectrometry (GCxGC-TOFMS). This thesis first presents the application of existing multivariate statistical models developed using UK tar samples to tar samples from the USA as well as identifying 947 individual compounds present within the tars. This has important implications as this study demonstrated that statistical methods developed using UK tar samples can be successfully applied to non-UK tars. The thesis then presents the application of post extraction derivitisation to a creosote samples allowing for the detection of 255 compounds, the majority of which would not be detected without derivitisation. The analysis also detected 1505 individual compounds within the Creosote and provides the most comprehensive list of compounds detected within Creosote that has been produced. The analysis was also able to suggest the production process for the tar from which the Creosote was distilled. The use of both derivitisation and GCxGC were vital in providing this forensic information. The thesis then presents the analysis of 16 tar samples using GCxGC and post extraction derivitisation and the production of a database of 2373 individual compounds detected within the tar samples. The study showed that 163 individual compounds were present within all tar samples regardless of the production processused. This has important implications as environmental assessment usually focuses on a limited number of compounds, which could be expanded using the database presented within this thesis. Finally the thesis presented a study that analysed a sample of Pintsch Gas tar, which has never previously been analysed using a mass spectrometer and produced a unique dataset.

The performance of supported palladium catalysts that had been modified with triphenyl phosphine, diphenyl sulfide and triphenyl amine was compared to unmodified Pd/TiO2 catalysts. It was found that the selectivity was superior to the unmodified catalysts with or without the use of carbon monoxide as a modifier. Ethylene selectivities in excess of 70 % at conversion levels greater than 80% were observed on the modified catalysts under conditions of excess hydrogen which compares extremely well with other catalysts found in the literature. The modifier was found to significantly reduce the number of high energy sites on the surface on the palladium, thereby significantly hindering ethylene hydrogenation but not affecting acetylene hydrogenation. The simple preparation of these catalysts together with the simplicity added by not having to use carbon monoxide or limited hydrogen promises a viable alternative strategy for commercial catalysis.

No description available.