Synthetic and naturally occurring calcium and magnesium carbonate minerals are widely used in a range of industrial and environmental applications where the mineral quality and purity is often critical for their intended use. Hence accurate characterisation of the mineral assemblages is essential. Equally important is an understanding of the chemical and physical pathways leading to mineral formation and their roles in carbon sequestration from greenhouse gases. This study investigates the application of Raman and infrared spectroscopies to Ca-Mg carbonate analysis. A full quantitative calibration has been achieved for quaternary mixtures by Raman spectroscopy (RS) employing monovariable and multivariable methods. The method was validated by X-ray powder diffraction (XRD). The lowest error on component values was obtained by Principal Component Regression with application of Standard Normal Variate. The quantifications show that RS is comparable to XRD. The effect of particle size on the fundamental vibrations of the [CO32-] anion in calcite is investigated by mid-infrared and RS. While the effect of particle size on the infrared signature of internal modes of the [CO32-] anion is well documented, this thesis documents associated changes in Raman spectra as a function of particle size. With decreasing size spectral contrast diminishes and changes in the relative ratios of the internal modes occur. For RS the turnaround from optically thick to thin material occurs in the 42-59 μm size range with further changes occurring at ≤ 5 μm. RS was also utilized to monitor carbonate reaction kinetics after dissolution of [Mg(OH)2] by CO2 sparging in the presence of calcium salts at 35 °C, 30 days duration. Four experiments employing different calcium salts, Ca:Mg ratios and effect of hydromagnesite [Mg5(CO3)4(OH)2.xH2O] seeding were examined utilizing vibrational spectroscopies, XRD and SEM. Results suggest that carbonate mineral paragenesis is driven by geochemical feedback between a range of calcium and magnesium carbonate dissolution-precipitation events where decomposition of nesquehonite [Mg(HCO3,OH)∙2H2O] leads to formation of magnesium carbonate hydrates [Mg5(CO3)4(OH)2.xH2O]. XRD confirmed that these hydrated phases contain 8 and/or 5 molecules of crystalline water. However, RS cannot distinguish these phases. Traces of barringtonite [Mg(CO3)∙2H2O] found at the end of experiments were interpreted as an indicator of incongruent dissolution of nesquehonite. Findings suggest that the Raman active ν1 mode of barringtonite is situated at ca. 1094-1095 cm-1. The limitations of Raman analysis in the context of mineral assemblage quantification, short range ordering and particle size effects are discussed in the context of these findings.

A systematic series of high-silica fluoride MFI zeolites were efficiently synthesised using a variety of shape and size structure directing agents. The effects of these structure directing agents on the zeolite synthesised have been studied by the complementary use of X-ray diffraction and solid state NMR. These 14N, 13C and 29Si NMR experiments yield information about the orientation of the structure directing agent within zeolite pores. They also identify covalently bonded fluoride in the form of pentacoordinated silicon whereby the first case of static and dynamic ordering of fluoride in the same zeolite is discovered by changing the structure directing agent. A two-dimensional solid state NMR experiment has also been used to study 13C isotopically labelled silicalite-1 synthesised using n-methyltributylammonium iodide. The double cross polarisation (DCP) experiment allows the distance to be determined between the structure directing agent and silicon framework for the first time in a zeolite system using NMR. This experiment has the potential to be replicated for silicalite-1 zeolites synthesised using alternate structure directing agents or for other zeolites systems.

The hydrothermal syntheses of new complex pyrochlore and perovskite oxide materials have been explored. Disorder is prevalent in these materials, so their structures and properties were investigated using a wide range of techniques. New pyrochlore oxides with compositions (Na0:60Bi1:40)(Fe1:06Mn0:17Bi0:77)O6:87 and (K0:24Bi1:51)(Fe1:07Mn0:15Bi0:78)O6:86 were hydrothermally produced in solutions of NaOH or KOH, respectively, at 200oC for 6 hours. These pyrochlores are metastable, decomposing at ca 400oC, suggesting their formation would be impossible through conventional solid state synthesis. Their average structures were studied and are described by Fd3m symmetry, with considerable disorder present in the A2O0 network. Investigation of their local structures through total scattering confirms the extent of disorder within these materials, showing significant deviation from the average structure. RMC was used to model accurately this disorder; resulting in interesting atomic arrangements for the A and O0 sites. The presence of Fe3+ and Mn4+ within these disordered structures leads to spin-glass type magnetic behaviour, with no observed long-range ordering interactions, typical of geometrically frustrated pyrochlores. A new mixed rare-earth chromite LaxSm1{xCrO3 perovskite solid solution (x = 0.0, 0.25, 0.5, 0.625, 0.75, 0.875, and 1.0) was prepared by single-step hydrothermal reaction at 370oC for 6 hours. The distorted perovskite structures are described by orthorhombic space group Pnma, whilst XRD and Raman scattering confirms the increasing structural distortion towards SmCrO3. The hydrothermal treatment results in dendritic-type crystallites, shown by STEM, offering greater homogeneity of particle size over solid state methods. Magnetometry reveals the onset of antiferromagnetic ordering of Cr3+ spins below room temperature, with magnetic interactions below these temperatures greatly dependent upon the structural distortion and samarium content. Spin-phonon coupling effects and switchable polarisations were observed at temperatures corresponding to magnetic events, suggesting these phenomena are spontaneously induced by magnetic interactions. A study of A site cation size variance effects in mixed rare-earth orthochromites was performed on Y0:5Ho0:5CrO3, La0:5Sm0:5CrO3, and La0:5Tb0:5CrO3 solid solutions, prepared through both hydrothermal and solid state methods. Increased variance in the La-Tb system resulted in separation of the two rare-earths in local layers, observed by atomically-resolved EELS, whilst attempts to make La-Ho solid solutions were not possible as the A site radius variance was too great. Separate rare-earth regions were observed in the solid state sample on the nano-scale, showing that greater homogeneity was achieved through hydrothermal synthesis. The homogeneity of rare-earth cation mixing also in uenced the magnetic properties of these materials, with dramatic changes being observed upon annealing the layered hydrothermal material.

The Hsü Kao Seng Chuan [Chinese characters omitted] biography of Chi Tsang [Chinese characters omitted] (Taishō 2060, T.50.513c-5l5a) is translated. It is preceded by a discussion of Chi Tsang's place in the history of Chinese Buddhism - he was a prominent exegete of the San Lun school, the Chinese counterpart to the Indian Mādhyamika School. The place of the Mādhyamika school in Indian Buddhism is discussed, as well as the history of its introduction into China. This is followed by a discussion of the nature of the sources for Chi Tsang's life - principally the Hsü Kao Seng Chuan notice - and the general unreliability and lack of depth of such accounts is discussed. The outstanding features of Chi Tsang's life are then discussed. He studied with Pa Lang, great re-vivifier of San Lun. He wrote abundantly and was renowned as a great lecturer. His interest encompassed the numerous Buddhist activities of his time, and his writings on the San Lun are the best we possess; on the Lotus sūtra, among the very best. He wrote commentaries to at least fifteen sutras. He disciples transmitted his teaching into the T'ang and to Japan, and he is reckoned the founder of the San Lun school. He was born in 549 and died in 623, and enjoyed the patronage of the Ch'en, Sui and T'ang ruling houses.̈̈ / Arts, Faculty of / Asian Studies, Department of / Graduate

Loulo is a world-class orogenic gold district in SW Mali. The mininig district is comprised of two major operational mines at Yalea (6.5 Moz at 4.7 g/t) and Gara (3.7 Moz at 4.1 g/t), plus numerous satellite deposits and other prospective targets, which takes Loulo's overall resource to 14.4 Moz. Two distinct types of ore deposit are recognised. Gara-style deposits are Fe-rich and characterised by a Fe-Cu-REE-Au-Ni-W-As ± Co-Ag-Pd metal association. Yalea-style, As-rich, deposits exhibit more typical orogenic gold features with a metal signature consisting of Fe-As-Cu-W-Au-Pb-Sb-Ag. Investigations into the source and composition of the auriferous fluids indicate two styles of ore fluid were responsible for mineralisation: (1) a 'Gara-style' oxidised (FM-buffered), high temperature (>400 °C), hypersaline (35-55 wt.% NaCl equiv.), Na-Fe-Cl-B-bearing magmatic fluid; and (2) a 'Yalea-style' reduced (QFM-buffered), lower temperature (300-350 °C), low-salinity (<10 wt.% NaCl equiv.) C0[sub]2-N[sub]2-H[sub]2S-rich metamorphic fluid. The identification of hypersaline Na-Fe chloride-rich fluid inclusions questions the metamorphic fluid paradigm for orogenic gold deposits. Field, petrographic and isotopic studies also provide convincing evidence that magmatic fluids played an integral role in gold mineralisation. These include: (1) the presence of a significant boron anomaly along the length of the Senegal-Mali Shear Zone (which hosts Loulo and other large gold deposits such as Sadiola), typified in Loulo by the presence of large volumes of replacive epigenetic tourmaline; (2) widespread pink sodic alteration; (3) the spatial association with iron oxide-copper-gold (IOCG) deposits in the adjacent Falémé district in Senegal; (4) the presence of Ni-Co sulphides and abundant REE-W minerals in the ore paragenetic assemblage; and (5) carbon isotopes overlapping the magmatic field (e.g. Gara vein ankerites show [delta][sup]13C compositions from -14.4 to -4.5%). Both metamorphic and magmatic fluids were capable of carrying gold as either bi-sulphide complexes or oxidised chloride complexes, respectively. In the Gara-style orebodies, mineralisation was controlled by the mixing of these two fluids, which resulted in changes in temperature, pH and f0[sub]2, and caused retrograde boiling ofthe CO[sub]2 component. This style of Loulo orebody contains distinct mineralogical and fluid inclusion characteristics, and it is therefore proposed that Gara-style orebodies represent a new sub-class of orogenic gold deposit, with evidence suggesting possible links with IOCG/skarn mineralisation. In the Yalea-style orebodies, mineralisation is confined to metamorphic fluids with the principal mineralisation trap linked to fluid immiscibility during fluctuations in pressure and/or temperature, and fluid-rock interactions with reduced host sediments. Chemisorption processes may also have played a role in gold deposition to account for the high levels of refractory gold in arsenopyrite.

Vermiculite is a clay mineral that is generally used for a wide range of applications such as in agricultural, horticultural and construction industries. This is due to its various properties which include high porosity, lightweight, thermo-insulating, non-toxic and good absorption capacity when exfoliated. The objective of this research was to critically evaluate the fundamental interaction of electromagnetic waves with vermiculite from different source locations and to understand the mechanism of exfoliation in an applied microwave field. When vermiculite minerals are placed under the influence of high electric fields, they expand due to the rapid heating of their interlayer water, which subsequently builds up pressure that pushes apart the silicate structure. The degree of exfoliation is directly related to the intensity of the applied electric field. The principal areas covered in this thesis include: a detailed review of the fundamentals of microwave processing and issues surrounding scale up; a critical literature review of vermiculite mineralogy, and previous methods of vermiculite processing and their limitations; understanding the interaction of microwave energy with vermiculite by carrying out mineralogical and dielectric characterisation; microwave exfoliation tests of vermiculite minerals from different source locations and a comparative energy and life cycle analysis of microwave and conventional exfoliation of vermiculite. A detailed review of the literature revealed that conventional exfoliation of vermiculite by gas or oil fuelled furnaces has significant limitations such as emissions of greenhouse gases, high-energy requirements (greater than 1 GJ/t), health and safety issues and poor process control. All work reported so far on microwave exfoliation of vermiculite has been limited to laboratory scale using domestic microwave ovens (2.45 GHz, power below 1200 W) and the route to scale up the process to industrial capacity has not given due consideration. Mineralogical characterisation of vermiculite from different geographical locations (Australia, Brazil, China and South Africa) revealed that only the sample from Brazil is a pure form of vermiculite while the other samples are predominantly hydrobiotite. All the samples have varying degrees of hydration with the Brazilian sample having the highest total water content. The presence of water in any form in a material influences its dielectric response and ultimately the microwave absorbing properties. The dielectric characterisation carried out on the different vermiculite samples shows that the vermiculite mineral structure is effectively transparent to microwave energy, but it is possible to selectively heat microwave absorber, which is the interlayer water in the vermiculite structure. The continuous microwave exfoliation tests carried out at both pilot scale at 53-126 kg/h and the scaled up system at 300-860 kg/h demonstrated that microwave energy can be used for the industrial exfoliation of vermiculite at high throughputs and is able to produce products below the specified product bulk densities standard required by The Vermiculite Association (TVA). The degree of vermiculite exfoliation depends on factors such as power density, feedstock throughput, energy input, interlayer water content, particle size of the feedstock, and vermiculite mineralogy. The highest degree of exfoliation was recorded for the Brazilian sample, which also had the highest water content. Life cycle analysis (LCA) frameworks by the International Organisation for Standardisation (The ISO 14040: principles and framework and ISO 14044: Requirements and guidelines) and British standards institution (PAS2050) were used to carry out comparative life cycle analysis of vermiculite exfoliation using microwave heating and conventional (industrial and Torbed) heating systems. The results showed that the microwave system potentially can give an energy saving of about 80 % and 75 % over industrial and Torbed Exfoliators respectively, and a carbon footprint saving potential of about 66 % and 65 %. It can be concluded that the reduced dust emission and noise from the microwave system would improve the working conditions, health and safety. Furthermore, the methodology discussed in this project can be used to understand the fundamental of microwave interaction with perlite and expanded clay, which are minerals with similar physical and chemical compositions as vermiculite.

Michele Mae Covell. / Also issued as Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1989. / Includes bibliographical references (p. 253-256). / Supported in part by the Defense Advanced Research Projects Agency and monitored by the Office of Naval Research. N00014-89-J-1489 Supported in part by the National Science Foundation. MIP 87-14969 Supported in part by Sanders Associates, Incorporated.

S'ha realitzat un estudi sistemàtic dels llibres sagramentals de naixements i defuncions de l'arxiu de la Parròquia de Sant Salvador del Vendrell del segle XIX, amb tres objectius: estudi de la mortalitat, estudi de les causes documentades de mort i estudi del personal sanitari. S'han buidat 33.150 partides, 18.547 baptismes i 14.603 defuncions. La mortalitat global ha estat d'un 78,7%, amb un predomini dels albats (52,4%) respecte els adults (47,5%). Per sexes, destaca la mortalitat dels nens (52,2%) respecte les nenes (45,7%), i en els adults la dels homes (51,1%) respecte les dones (48,8%). Destaquen dos períodes de gran mortalitat: els anys 1808-11 amb la Guerra del "Francès", on predomina la mortalitat adulta, i el període 1854-58 amb l'epidèmia del còlera morbo, on predomina la mortalitat infantil. Només estan documentades les causes de mort en 658 registres (4,51% dels òbits), classificades com: violenta (12,48%), (12,48%), i per malaltia (75,19%). Han aparegut 63 sanitaris, en 176 partides (0,53%), on destaquen 14 metges, 12 farmacèutics i 8 llevadores. / We performed a systematic study of sacramental books of births and deaths of the file of the Parish of Sant Salvador del Vendrell in the nineteenth century, with three objectives: study of mortality, study of the documented causes of death and study of personnel healthcare.We have obtained 33,150 records 18,547 baptisms and 14,603 deaths. The overall mortality was a 78.7% with a predominance of children (52.4%) than adults (47.5%). For gender, highlights the mortality of children (52.2%) than girls (45.7%), and in the adult men (51.1%) than women (48.8%). There were two periods of high mortality: in the years 1808-11 by the War "French", where adult mortality prevails, and the period 1854-58 with the cholera epidemic, dominated by infant mortality. Only causes of death are documented in 658 records (4.51% of detahs), classified as violent (12.48%), accident (12.48%) and disease (75.19%). 63 Physicians have appeared in 176 records (0.53%), which include 14 doctors, 12 pharmacists and eight midwives.

The Lumwana Cu±Co deposits Malundwe and Chimiwungo are examples of pre-Katangan mineralized basement that are located in the Domes Region of the Lufilian Arc, an arcuate North neo-Proterozoic fold belt, which hosts the Zambian and Congolese deposits that make up the Central African Copperbelt. The Lumwana deposits are situated within the Mwombezhi Dome; a Mesoproterozoic basement inlier consisting of highly sheared amphibolite grade schist to gneiss units that host the Cu±Co mineralization. Kinematic indicators such as s-c fabrics and pressure shadows on porphyroblasts suggest a top to the North shear sense. Peak metamorphism of 750ºC ± 25ºC and 13 ± 1 Kb indicated by whiteschist assemblages occurred during the Lufilian Orogeny at ~530Ma, with burial depths of ~50km. A major decollement separates the high pressure mineral assemblages of the basement from the lower pressure mineral assemblages of the overlying Katangan Supergroup. The age range and lithologies of the pre-Katangan basement of the Domes Region is similar to the pre-Katangan basement of the Kafue Anticline, which underlies the neo-Proterozoic Zambian Copperbelt deposits situated 220km to the SW. The origin of the protolith to the mineralization is ambiguous at Lumwana with transitional contacts from unmineralized quartz-feldspar±phlogopite basement gneiss to Cu±Co mineralized quartz-phlogopite-muscovite-kyanite-sulphide Ore Schist. The transitional contacts and structural controls on mineralization has led to the hypothesis that these deposits represent metasomatically altered, mineralized and sheared basement, rather than mineralized neo-Proterozoic sediments with amphibolite grade metamorphism. This hypothesis is supported by petrographic analysis, stable isotope analysis (δ34S), whole rock geochemistry, and electron microprobe analysis of ore and host rock assemblages. The transitional contacts observed at Lumwana are due to an alteration event associated with mineralization that removed feldspar from ore horizons resulting in depleted Na and Ca and relatively higher Al components. Sulphides are deformed by the S1 fabric and overprinted by kyanite which formed at peak metamorphism. This indicates that copper was introduced to the basement either syn or pre-peak metamorphism. Post S1 metamorphism with associated quartz-muscovite alteration has remobilized sulphides into low strain zones and pressure shadows around porphyroblasts. δ34SSULPHIDES give values of +2.3 to +18.5‰ that fall within the range of values observed in the Copperbelt of -17 to +23‰. The mechanism of ore formation at Lumwana was dominated by thermochemical sulphate reduction (TSR), indicated by the relatively heavy δ34S values and the absence of the light bacteriogenic δ34S values observed in the Copperbelt. Electron microprobe data of muscovite, phlogopite and chlorite show little variation between early and late mineral phases indicating that metamorphic homogenization of silicate assemblages occurred. The Lumwana deposits are large mineralized shear zones within the pre-Katangan basement. Various styles of basement mineralization are also observed in the Kafue Anticline and the structural controls on mineralization and lithological similarities to the Lumwana deposits suggests that pre-Katangan basement is a viable source for the Cu-Co budget of the Central African Copperbelt and that basement structures had a key role in its formation.

The doped perovskite manganite La1-xCaxMnO3 (0<x<1) has been extensively studied due to the interactions between the electronic, magnetic and crystal lattices, and the wide range of phases that can coexist. The region of greatest interest in the bulk material is around x~0.5, where there is often mesoscopic phase coexistence between a ferromagnetic metal (FM) and an antiferromagnetic insulator (AF). The first part of the dissertation describes a systematic study on a series of La1-xCaxMnO3 films deposited onto SrTiO3 (001) by pulsed laser deposition with compositions in the range 0.40<x<0.45. From electrical transport and magnetisation measurements, the limit of metallic behaviour was found to be x=0.41 whereas ferromagnetism was seen up to x=0.45. Although the transition temperatures of 150-200 K were comparable with the bulk material, the saturation moment at 20 K was about 40% of the fully spin-aligned value, which suggests the possibility of a phase separated mixture of FM and AF regions. The deviation from the bulk behaviour is thought to be due to substrate-induced strain altering the crystal symmetry and making the cubic ferromagnetic state less favourable. In the remainder of this work, the nature of phase separation in 60 nm La0.59Ca0.41MnO3 and La0.60Ca0.40MnO3 films is investigated. The effect of an external magnetic field is studied. A high-field magnetoresistance (Δρ/ρB=0) of 41% in fields of 400 mT was observed for a La0.60Ca0.40MnO3 film, which, while not as large as the values previously reported in the literature, is still significant. The magnetic history of the films was found to be very significant, with the zero-field resistivity depending on the highest field applied. The isothermal time dependence of the resistivity was found to be exponential, with a time constant in the range 100-1000 s. Possible mechanisms for the MR effect and the dependence on magnetic history are discussed.