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Chapter One serves as an introduction to, and background information, on the thermal decomposition of metal oxalates and homonucleus carbonyl clusters. Emphasis is placed on the compounds under investigation, namely the oxalates of iron(II), cobalt(lI) and nickel(ll) oxalate dihydrate and their corresponding binary and ternary compounds, as well as triiron dodecacarbonyl and tetracobalt dodecacarbonyl. Topics specifically addressed are their structures as well as the thermodynamics of the dehydration and decomposition of compounds of this type. Given this background, the overall aims of the work are presented. These include finding the reaction conditions to form metal powders from metal oxalates, and a preliminary study of carbonyl clusters to see if they too may be used in the production of metal powders. Chapter Two gives the results of the dehydration and decomposition of the metal oxalates, characterised by way of infrared, scanning electron microscopy, X-ray diffraction and thermogravimetric analysis. The compounds under investigation are those of the single oxalates of iron, cobalt and nickel; the binary systems of Fe-Co, Fe-Ni and Co-Ni, in the molar ratios of 3:1, 1:1 and 1:3 for each system; and the ternary oxalate system in the molar ratios of Fe1 :Co1 :Ni1, Fe8:Co1 :Ni1, Fe1 :Co8:Ni1 and Fe1 :Co1 :Ni8. It was found that under certain reaction conditions all these compounds, excluding the ferrous oxalate dihydrate, decompose to the metal. It was found through experiments to modify the morphology of the crystals under investigation that the decomposition product is controlled by the crystal lattice system the starting material is synthesised in. When in the cobalt/nickel oxalate a-crystal system, decomposition is to the metal, or in the case of the binary and ternary systems, to the alloy. If the oxalate is synthesised in the crystal system of the iron oxalate, the resultant decomposition product is the respective oxide. Experiments were carried out on the iron/cobalt binary system to prove this hypothesis. Depending on the conditions of synthesis, the iron/cobalt binary system can form in either the crystal system analogous to iron (1), or analogous to cobalt (2). The products of pyrolysis for each case differs, with (1) decomposing to the oxide and (2) decomposing to the alloy. iii Chapter Three is a brief, preliminary study describing the thermal decomposition of triiron dodecacarbonyl and tetracobalt dodecacarbonyl. Characterisation of the pyrolysis products is given by infrared, scanning electron microscopy, X-ray diffraction and thermogravimetric analysis. A tentative theory for their decomposition route under an atmosphere of nitrogen is given. It was found that neither compound decomposed fully to the central metal, but that a mixture of oxide and metal were left. The conclusion reached from this study was that neither carbonyl under investigation was particularly successful. Although in both instances metal was produced, both contained large amounts of the respective oxide. This makes them unsuitable for an industrial application to form metal powders. Chapter Four describes in detail the all the experimental, materials, methods, techniques and equipment used in this study. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2001.

Nickel-boron coatings are used to improve friction and wear properties (and, in some cases, corrosion resistance). The nickel-boron coating investigated here is 5-6 wt% boron, and is deposited by electroless plating on a 1018 steel substrate. It is amorphous as-plated, and heat treatment is used to crystallize the coating to improve its hardness. To better understand and predict the effects of heat treatment, samples that had been isothermally annealed at various temperatures from 500ºC to 800ºC for either 2h or 5h were examined by several methods to determine the diffusion effects taking place during annealing. Samples were examined by XRD, both at the coating surface and at multiple depths within the coating. Optical microscopy and SEM were used to view the structure of the coating in cross-section. Cross sections were etched and examined by optical microscopy and SEM, as well as EDS, which was used to develop a Ni-Fe composition profile at the coating-substrate interface. Microhardness measurements were taken and used to develop microhardness profiles. Additional samples were annealed to investigate boron oxidation at the coating surface. Based on the data, there is a reduced amount of Ni3B near the outer surface of the heat-treated coatings, with the thickness of the resultant γ-Ni layer increasing with annealing time and temperature, from 2.4 to just over 13 µm. This low-boron region indicates that boron is diffusing out through the surface of the coating and oxidizing, which the literature indicates should result in the formation of B2O3. Because B2O3 is water-soluble, it is likely that it dissolved during the water quench that concluded most anneals. Diffraction and EDS data also indicate interdiffusion of the nickel in the coating and the iron in the steel substrate. This leads to the formation of a soft interdiffusion layer between the Ni3B coating bulk and steel substrate that appears to be a mix of ferrite and Ni3Fe.

ITO is a wide band gap semiconductor material, its band gap is from 4.7 eV to 5.2 eV. Due to the low resistivity, high transmittance to visible light, great absorption to UV light, and high reflection to IR, ITO is wide used to photovoltatic application; such as anodic electrode of Liquid Crystal Display (LCD) and photovoltaic devices. In the thesis, samples are deposited with an ITO layer on color filter (CF) by magnetron sputtering. The conductivity of samples is measured by 4-probe measurement, and the transmittance is characterized by visible spectroscopy. In this work is heat treatment parameters of temperature and annealing time of ITO thin film know been studied, and found an optima condition. From the experiment results, an optima heat treatment condition is temperature of 200¢Jfor 40 minutes, which reveals lower resistivity and improved transmittance of ITO samples. And, it is less process time and lower treatment temperature to used condition for industry presently. The reducing time of heat treatment will increase 9.9 % production, and enhancing the properties of color filter. Depending on the results of this work, there is space to improve performance and reduce power for fabrication of color filter.

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RNA molecules isolated from FFPE samples are highly fragmented and modified, and generally deemed unsuitable for downstream gene expression profiling. With the development of molecular biology, there has been growing interest in profiling archival FFPE samples. Successful profiling of transcripts from FFPE samples would greatly expand tissue sources for large scale gene expression studies; also it would pave the way for future applications on the type of tissue readily available in the clinical setting. So far, there is a lack of systemic studies evaluating the quality of RNA isolated from routinely processed FFPE samples, and it has remained difficult to assess how well FFPE-derived RNA mirrors the status of RNA isolated before fixation. In this project, the similarity of miRNA and mRNA profiles between matched frozen and FFPE lymphoid hyperplasia tissues (N=7 for miRNA comparison, N=4 for mRNA comparison) were evaluated. We found consistently good correlation (mean of Pearson coefficient=0.939, mean of Spearman coefficient=0.905, mean of Kendall tau=0.744) between matched frozen and FFPE-derived miRNA profiles, suggesting FFPE samples may retain miRNA expression information quite well. This has major positive implications for research using FFPE samples, as miRNA profiling becomes more prominent in bioprofiling studies. On the contrary, mRNA isolated from FFPE samples showed less correlation (Spearman coefficient less than 0.75) with its frozen counterpart on the Agilent microarray platform. With a post extraction heat treatment aimed at reversing base modifications and cross linking structures, obvious global mRNA quality improvement was observed in cases where samples appeared to be heavily cross linked, but was less effective and even detrimental in cases where cross linking was less prominent. This research suggests that the extent of cross linking may be critical in terms of determining whether a particular FFPE tissue will become a useful source of mRNA for global profiling studies / Thesis (Master, Pathology & Molecular Medicine) -- Queen's University, 2008-09-26 10:49:50.044