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Siu, King Sang = 網狀合金的白鑄鐵的退火處理 / 蕭健生. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references. / Abstracts in English and Chinese. / Siu, King Sang = Wang zhuang he jin de bai zhu tie de tui huo chu li / Xiao, Jiansheng. / Abstract --- p.i / 摘要 --- p.iv / Acknowledgments --- p.v / Table of contents --- p.vi / List of table captions --- p.viii / List of figure captions --- p.ix / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Composite Materials --- p.1 / Chapter 1.2 --- Nanostructured Material --- p.2 / Chapter 1.3 --- Typical Methods of Fabrication of Nanostructure Material --- p.3 / Chapter 1.4 --- Combination of the Ideas of Nanostructure and Composite --- p.4 / Chapter 1.5 --- Phase Separation --- p.5 / Chapter 1.6 --- Nucleation and Growth --- p.6 / Chapter 1.7 --- Spinodal Decomposition --- p.8 / Chapter 1.7.1 --- The Initiation of Spinodal Decomposition --- p.8 / Chapter 1.7.2 --- Dynamics of Spinodal Decomposition --- p.9 / Chapter 1.7.2.1 --- Classical Equation of Diffusion --- p.9 / Chapter 1.7.2.2 --- Factors Deterring Spinodal Decomposition and Formation of Spinodal Network --- p.10 / Chapter 1.7.3 --- Relationship between Wavelength of Spinodal Network and Undercooling --- p.11 / Chapter 1.7.4 --- "Comparing Nucleation and Growth, and Spinodal Decomposition" --- p.11 / Chapter 1.8 --- How to achieve large undercooling --- p.12 / Chapter 1.9 --- Thermal annealing --- p.12 / Chapter 1.9.1 --- Recovery --- p.13 / Chapter 1.9.2 --- Recrystallization --- p.13 / Chapter 1.9.3 --- Grain Growth --- p.14 / Chapter 1.9.4 --- Equation of Ideal Grain Growth --- p.14 / Chapter 1.9.5 --- Factor that slow down grain growth --- p.15 / Chapter 1.10 --- Prospect of this Thesis Project --- p.16 / References --- p.17 / Figures --- p.19 / Chapter Chapter 2 --- Experimental Method / Chapter 2.1 --- Introduction --- p.26 / Chapter 2.2 --- Sample Fabrication --- p.26 / Chapter 2.3 --- Procedures for Preparing Thermal Annealing --- p.26 / Chapter 2.3.1 --- Preparation of Vacuum Environment --- p.26 / Chapter 2.3.2 --- Sealing Silica Tube --- p.27 / Chapter 2.4 --- Furnance --- p.27 / Chapter 2.5 --- Samples Analysis --- p.27 / Chapter 2.5.1 --- Optical Microscope --- p.27 / Chapter 2.5.2 --- Scanning Electron Microscope (SEM) Analysis --- p.27 / Chapter 2.5.3 --- Transmission Electron Microscope (TEM) Analysis --- p.28 / Chapter 2.5.3.1 --- Sample Preparation --- p.28 / Chapter 2.5.3.1.1 --- "Grinding, Polishing and Pouching" --- p.28 / Chapter 2.5.3.1.2 --- Dimpling --- p.29 / Chapter 2.5.3.1.3 --- I on Milling --- p.29 / Chapter 2.5.3.2 --- Phase Identification --- p.30 / References --- p.31 / Figures --- p.31 / Chapter Chapter 3 --- Grain Growth in Fe81C17Si5 / Chapter 3.1 --- Abstract --- p.34 / Chapter 3.2 --- Introduction --- p.35 / Chapter 3.3 --- Experimental --- p.36 / Chapter 3.4 --- Result --- p.37 / Chapter 3.5 --- Discussion --- p.44 / References --- p.48 / Figures --- p.49 / Chapter Chapter 4 --- High temperature thermal annealing of Fe81C14Si5 network alloys / Chapter 4.1 --- Abstract --- p.74 / Chapter 4.2 --- Introduction --- p.75 / Chapter 4.3 --- Experimental --- p.76 / Chapter 4.4 --- Result --- p.77 / Chapter 4.5 --- Discussion --- p.83 / References --- p.86 / Figures --- p.87

by Yim-kam Kwong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 119-133). / ACKNOWLEDGEMENT --- p.vii / LIST OF TABLES --- p.viii / LIST OF FIGURES --- p.x / ABSTRACT --- p.1 / SECTION / Chapter 1. --- INTRODUCTION --- p.3 / Chapter 2. --- LITERATURE REVIEW --- p.6 / Chapter 3. --- MATERIALS AND METHODS --- p.39 / Chapter 4. --- RESULTS --- p.61 / Chapter 5. --- DISCUSSION --- p.103 / Chapter 6. --- CONCLUSION --- p.116 / REFERENCES --- p.119 / APPENDIX --- p.134 / Chapter SECTION 1 --- INTRODUCTION --- p.3 / Chapter SECTION 2 --- LITERATURE REVIEW --- p.6 / Chapter 2.1 --- IRON --- p.6 / Chapter 2.1.1 --- CHEMISTRY --- p.6 / Chapter 2.1.2 --- METABOLISM --- p.6 / Chapter 2.1.2.1 --- Homeostasis --- p.6 / Chapter 2.1.2.2 --- Absorption --- p.8 / Chapter 2.1.2.3 --- Transportation - Role of transferrin in iron transport --- p.9 / Chapter 2.1.2.4 --- Storage --- p.10 / Ferritin --- p.11 / Haemosiderin --- p.13 / Chapter 2.2 --- IRON OVERLOAD --- p.14 / Chapter 2.2.1 --- AETIOLOGY --- p.14 / Chapter 2.2.2 --- PREVALENCE --- p.15 / Chapter 2.2.3 --- MECHANISM --- p.16 / Chapter 2.2.4 --- PATHOLOGY OF IRON OVERLOAD --- p.17 / Chapter 2.2.4.1 --- Increased absorption of iron from the diet --- p.18 / Chapter 2.2.4.2 --- Parenteral administration of excess iron --- p.21 / Chapter 2.2.4.3 --- Increased iron absorption combined with transfusional overload --- p.22 / Chapter 2.2.4.4 --- Miscellaneous conditions --- p.23 / Chapter 2.2.5 --- CLINICAL PRESENTATION --- p.24 / Chapter 2.2.6 --- EFFECT OF IRON OVERLOAD --- p.25 / Chapter 2.2.6.1 --- Role of iron in lipid peroxidation --- p.25 / Chapter 2.2.6.2 --- Iron and neoplasia --- p.26 / Chapter 2.3 --- ASSESSMENT OF IRON OVERLOAD --- p.26 / Chapter 2.3.1 --- NON-SERUM PARAMETER --- p.26 / Chapter 2.3.1.1 --- Localization of stored iron --- p.27 / Chapter 2.3.1.2 --- Morphometric assessment of hepatic iron in liver biopsy --- p.30 / Chapter 2.3.1.3 --- Hepatic iron concentration --- p.31 / Chapter 2.3.1.4 --- Atomic absorption spectrophotometry --- p.32 / Chapter 2.3.1.5 --- Hepatic imaging studies --- p.33 / Chapter 2.3.2 --- SERUM PARAMETERS --- p.34 / Chapter 2.3.2.1 --- Serum ferritin measurement --- p.34 / Chapter 2.3.2.2 --- Serum iron --- p.36 / Chapter 2.3.2.4 --- Transferrin saturation --- p.37 / Chapter SECTION 3 --- MATERIALS AND METHOD --- p.39 / Chapter 3.1 --- SUBJECTS --- p.39 / Chapter 3.1.1 --- SOURCE OF TISSUE SAMPLES AND CASE SELECTION --- p.39 / Chapter 3.1.1.1 --- The controls --- p.39 / Chapter 3.1.1.2 --- The transfusion group --- p.39 / Chapter 3.1.1.3 --- The non-transfusion group --- p.40 / Chapter 3.1.1.4 --- The total group --- p.40 / Chapter 3.2 --- METHODS --- p.40 / Chapter 3.2.1. --- HISTOLOGICAL METHOD --- p.44 / Chapter 3.2.1.1 --- Haematoxylin and Eosin Stain --- p.47 / Chapter 3.2.1.2 --- Perls' Prussian Blue Method --- p.49 / Chapter 3.2.1.3 --- The Rowe's Method of Iron Deposition --- p.47 / Chapter 3.2.1.4 --- Method 1 --- p.48 / Chapter 3.2.1.5 --- Method2 Estimation and grouping of % area --- p.49 / Chapter 3.2.1.6 --- "Comparison of Rowe's method, and the two histological iron grading methods" --- p.54 / Chapter 3.2.2 --- CHEMICAL MEASUREMENT --- p.55 / Chapter 3.2.2.1 --- Sectioning of paraffin liver blocks for chemical measurement --- p.55 / Chapter 3.2.2.2 --- Paraffin removal --- p.56 / Chapter SECTION 4 --- RESULTS --- p.61 / Chapter 4.1 --- HISTOLOGICAL ASSESSMENT --- p.61 / Chapter 4.1.1 --- HISTOLOGICAL STUDY --- p.61 / Chapter 4.1.2 --- SEX DISTRIBUTION --- p.65 / Chapter 4.1.3 --- AGE DISTRIBUTION --- p.65 / Chapter 4.2 --- CHEMICAL MEASUREMENT --- p.81 / Chapter 4.2.1 --- EVALUATION OF ANALYTICAL PRECISION --- p.84 / Chapter 4.2.2 --- RESULT OF CHEMICAL MEASUREMENTS --- p.81 / Chapter 4.2.3 --- ASSOCIATED CONDITIONS IN PATIENTS WITH LIVER TISSUE IRON > 50 μMOL/G --- p.86 / Chapter 4.3 --- CORRELATION OF HISTOLOGICAL ASSESSMENT WITH CHEMICAL MEASUREMENT --- p.88 / Chapter 4.3.1 --- CORRELATION OF HISTOLOGICAL ASSESSMENT WITH CHEMICAL MEASUREMENT BY METHOD 1 --- p.88 / Chapter 4.3.2 --- CORRELATION OF ASSESSMENT WITH CHEMICAL MEASUREMENT BY METHOD 2 --- p.89 / Chapter 4.3.2.1 --- Percentage area --- p.95 / Chapter 4.3.2.2 --- Score --- p.96 / Chapter 4.4 --- PANCREATIC AND MYOCARDIAC HAEMOSIDEROSIS --- p.100 / Chapter 4.4.1 --- METHOD 2 --- p.100 / Chapter SECTION 5 --- DISCUSSIONS --- p.103 / Chapter SECTION 6 --- CONCLUSIONS --- p.116 / REFERENCES --- p.119 / APPENDIX --- p.134

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The validity of the Homsey method for heme iron, modified Schricker and sodium pyrophosphate extraction methods for nonheme iron and atomic absorption spectrophotometry (AAS) and ferrozine methods for total iron were determined using spikes of hemoglobin, ground beef baked to different degrees of doneness, proportional beef liver:catfish mixtures and National Institute of Science and Technology reference materials. The mean spike recoveries of 0.0lg and 0.02g Hb in raw beef and raw chicken samples were 96.7% of the heme iron for the Homsey method, 97.9% of the total iron for the ferrozine method, and 85.7% of the total iron for the AAS technique. In ground beef patties baked rare, medium and well-done, the nonheme iron values increased with Heme and nonheme iron values were plotted against beef liver concentrations in the beef liver:catfish mixtures, and the correlation coefficients obtained were 0.994 for the Homsey method, 0.991 for the modified Schricker method, and 0.995 for the sodium pyrophosphate method. Heme iron plus nonheme iron equalled total iron for all the mixtures. Student's t test revealed no significant difference between ferrozine total iron values and NIST-certified concentrations, but the AAS total iron values were significantly (p<.05) The Hornsey method was validated for all samples except well-done beef. The two nonheme iron methods were reliable and accurate. While the fenozine technique was consistent, reliable and accurate, the AAS method was able to detect, on an average, only 80-85% of the total iron present. There was no interference of the sample mineral matrix with the detection ability of the AAS method.

Thesis (M. Sc. ( Physics)) -- University of Limpopo, 2020 / In this work, we present first-principles calculation on the structural, thermodynamic, mechanical and electronic stabilities of Fe-Al and FeAl-X (X: Pt, Pd, Ru and Ag) alloys at lower and high temperatures. These systems have recently attracted a lot of attention for both scientific and possible technological application in turbines, Steel-It coating, energy sector, boilers, pipes and automotive parts as a potential replacement of steel due to their excellent resistance to oxidation at high temperatures. However, they suffer limited room temperature ductility and a sharp drop in strength above 873 K. We determined the lattice parameters, heats of formation, elastic constants, bulk to shear moduli, density of states, phonon dispersion curve and X-ray diffraction pattern for binary and ternary system at various concentrations between 0 ≤ x ≤ 10. Furthermore, the lattice expansion, elastic constants, Gibbs free energy, X-ray diffraction pattern and radial distribution function were done on the most stable systems to determine the melting point of FeAl-X ternary systems. A systematic investigation was performed on the stability of the Fe-Al alloys at zero K. We employed CASTEP code to evaluate the thermodynamic, elastic and electronic stability. Virtual crystal approximation was used to determine various atomic concentrations (0 ≤ x ≤ 5) of both Pt and Ru; this allowed more precise predictions on the materials’ behaviour. Further analysis was done on the density of states to describe the behaviour of each phase near the Fermi level; these phases were observed at different percentage compositions. A supercell approach, DMol3 was also used to evaluate these systems at a larger scale (0 ≤ x ≤ 50). VASP and LAMMPS codes were used to determine the stability of these FeAl-X ternary systems at concentrations (0 ≤ x ≤ 10). It was found that the equilibrium lattice parameters of the binary systems are in good agreement to within 2% with the available experimental data. The heats of formation showed that β2 FeAl phase was the most energetically stable system since it displayed the lowest value compared to all other binary systems. This observation accord well with the experimental phase diagram. It was also confirmed from the corresponding electronic DOS behaviour near the Fermi level. Furthermore, the shear modulus (C’) of these Fe-Al binary systems, i.e. FeAl, Fe2Al5, Fe4Al13, Fe5Al8, Fe2Al and FeAl3 were found to be positive fulfilling the condition of stability. The Fe2Al5 system was found to be the second most stable phase, followed by the monoclinic structure Fe4Al13. This observation was confirmed from the total DOS (where the Fermi level falls in the pseudogap, condition of stability). We further employed virtual crystal approximation and supercell approaches to model various atomic compositions at 0 ≤ x ≤1 and 0 ≤ x ≤ 50 for Ag, Pt, Pd and Ru. The heats of formation, density of states and elastic constants were determined to describe the structural, thermodynamic and mechanical stability of these systems. It was found that the addition of Ag, Pt, Pd and Ru enhances the stability at lower atomic percentage composition below 0.5%. Interestingly, the addition of Pt and Ru was found to significantly improve the ductility of the ternary FeAl-X compound for 0.2 and 0.5 at. % compositions. These systems showed that the Fe-sublattice was the preferred doping site with promising improvement in strength on the properties. It was further deduced that Ag and Pd stabilize the FeAl-X system at atomic percentage compositions of 0.5 and 0.7 respectively. Furthermore, a molecular dynamics-based LAMMPS-EAM was employed to model Fe50-XXXAl doped systems with either Ag, Pt or Pd. The lattice site preferences of the dopant were deduced from their energy landscape. More importantly, Ag and Pd doped systems gave comparable transition temperatures to experimental findings of 1273 K and 1073 K, respectively. Their thermodynamic and mechanical stability trends showed promising properties for industrial applications, displaying stability at a high temperature below 1300 K. This was evident for Ag, Pt (0.5 at %) and Pd (0.7 at %) doping as was the most stable systems with respect to Cij, ΔG, and RDF’s which indicated to influence the elastic instability above 1200 K as well as the ductility of these systems. The XRD confirmed that the doped systems preserved the structural symmetry as expected.

The fate of iron complexed by various organic compounds was investigated as a function of both chemical oxidative and coagulation removal methods. Dissolved organic carbon (DOC) utilized in the studies was obtained from a variety of sources and included humic and fulvic acids, tannic acid and oxalic acid. Oxidants evaluated were potassium permanganate, free chlorine, and chlorine dioxide. Both laboratory-scale and field monitoring studies were performed. The relative molecular weight distribution (MWD) of the DOC present was analyzed to evaluate how changes in this parameter affected the efficiency of soluble iron removal by oxidation. In addition, the MWD of selected coagulated samples was evaluated to determine how this parameter affected the fate of complexed iron during the coagulation of dissolved organic matter with alum. A high degree of ferrous iron complexation occurred with the DOC dominated by higher molecular weight organics. This complexation rendered the iron stable against the addition of each of the oxidants evaluated. However, soluble Fe(II) complexed by low molecular weight organics was successfully removed by chemical oxidation. Potassium permanganate was found to be the most effective oxidant of the three oxidants utilized in the study. The results indicated that soluble Fe(II) complexed by high molecular weight DOC can be efficiently removed by alum coagulation. The pH and alum dose utilized to produce effective DOC removal was also found to promote efficient complexed Fe(II) removal. / Master of Science