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X-ray diffraction techniques were used to determine thicknesses, and strains in sputtered polycrystalline thin films of molybdenum and titanium on silicon single crystal substrates. The thickness determination method used was an extension of a previous method wherein the orientation function determined from experimental data obtained in only a part of the angular range in chi could be fitted with Legendre polynomials and extrapolated to chi=90°. The fitted orientation functions were then used to accurately calculate the thickness of the thin films. The method proved to be theoretically consistent. The residual strain measurements completed on the thin films were determined using the sin²x method of analysis. Strains were determined from x-ray peak shifts and then plotted against sin²x. Tensile stresses were found to be present in the titanium sample while compressive stresses were present in the molybdenum sample. Lattice expansions were recorded in both film samples (as received condition). These expansions were correlated to the presence of argon as reported by previous authors. Other effects which could have produced additional residual strains were also noted (i.e., thermally induced dislocations, etc.). / Master of Science

Particulate reinforced Al alloy composites (AlMCs) are recognized as important structural materials due to their lightweight, high modulus and strength and high wear resistance. In order to understand the effect of matrix, reinforcement and secondary processing techniques on the microstructure development and mechanical properties of AlMCs produced by powder metallurgy routes, Al alloy composites reinforced with three types of reinforcements by different secondary processing techniques have been produced and examined. Fabrication of Al or 6061Al alloy based composites reinforced with nano-sized SiC particles (~500nm), micro-sized (<25µm) quasicrystalline alloy particles (hereinafter referred to as “NQX”) and micro-sized Nb particles (~130µm) has been carried out by powder metallurgy routes followed by extrusion or cold rolling. After extrusion, a homogeneous distribution of secondary particles has been obtained with rare interfacial reaction products. The 6061Al/SiC composites exhibit superior mechanical properties than either monolithic alloys or composites reinforced with micro-sized particles with retained ductility while the 6061Al/NQX and 6061Al/Nb composites show limited improvement in tensile strength mainly due to their reinforcement size and poor interfacial bonding. After cold rolling, the evolution in microstructure, texture and strength has been analysed. A typical near β fibre texture with highest intensities near Copper and Brass orientations has been developed for 6061Al/NQX and 6061Al/Nb composites. For 6061Al/SiC composites, a randomized texture with very small grains has achieved due to the presence of the non-deformable SiC particles. Mechanical property tests including microhardness, three-point bending tests and tensile tests have been carried out on cold rolled samples and the results exhibit some level of improvement when compared with as-extruded samples due to work hardening. Finally, the work moves on to the general discussion based on the previous result chapters. The microstructural development related to reinforcement, matrix and interfacial areas during extrusion and cold rolling has been summarised and the correlation between microstructure and mechanical properties has been discussed. The thesis provides a thorough understanding of AlMCs produced by powder metallurgy routes in terms of matrix, reinforcement and processing techniques. It can provide reference to the future development of AlMCs for high strength applications.

The Palmer Zone of Transpression (PZoT) in the Bronson Hill zone of central Massachusetts is an expression of late Paleozoic oblique convergence between Avalonia and Laurentia. The steeply W-dipping, N-S trending PZoT is defined by bounding high strain zones (Mt. Dumplin on west, Central Maine and Conant Brook on east) of opposing shear sense enclosing the Monson orthogneiss. Research was designed to establish the timing of deformation to test the hypothesis that strain in transpressional systems occurs contemporaneously. An understanding of the timing of deformation in this zone could elucidate the mechanisms that formed the zone and contribute to a greater overall understanding of fabric evolution in transpressional systems. U-Pb SIMS ages of zircon in deformed pegmatites in Monson orthogneiss and Paxton and Rangeley paragneisses are 369 to 364 Ma. Plutons that contain all fabrics associated with progressive transpression – lineations ranging from subhorizontal (initial) to steeply-plunging parallel to dip (final) – mark the maximum age of deformation. Ages range from 360-355 Ma in the Hardwick tonalite, Wachusett tonalite, West Warren diorite, Walker Mountain orthogneiss, and Nichewaug diorite, and indicate transpression in the PZoT initiated after ca. 355 Ma. Monazite from Rangeley paragneisses and schists selected in the context of petrofabrics and syn-deformational mineral assemblages yield U-Th-Pb EPMA chemical ages that indicate dextral transpression occurred continuously from 355 to 315 Ma. Monazite chemical ages also indicate that sinistral lateral displacement in the west-bounding Mt. Dumplin high strain zone initiated ca. 325 Ma and lasted for roughly 45 m.y., ending around 280 Ma. The data for the Central Maine zone, Conant Brook shear zone, and Greenwich syncline support the idea of contemporaneous deformation across the compartmentalized zones of a transpressive system (355-315 Ma), while the ages for the Mt. Dumplin high strain zone indicate sinistral lateral displacement overlapped dextral transpression by about 10 m.y. but generally continued later in time (325-280 Ma).

Semiconductor nanostructures have attracted great interest owing to their unique physical properties and potential applications in nanoscale functional devices. The enhancement of the physical properties of semiconductor nanostructures and their performance in devices requires a deeper understanding of their fundamental microstructural properties. Thus this thesis is focused on the experimental and theoretical studies of the microstructural properties of two important semiconductor nanostructures: axial heterostructured silicon nanowires with varying doping and indium nitride colloidal nanoparticles. In this thesis, axial heterostructured silicon nanowires with varying doping were synthesized on an oxide-removed Si{111} substrate using a vapour-liquid-solid approach. Their fundamental microstructural properties, including the crystalline structure, wire growth direction and morphologies, were studied using various characterization techniques. It is found that a very small fraction of the silicon nanowires crystallize in a hexagonal (wurtzite) phase, which is thermodynamically unstable in bulk silicon under ambient conditions, while a large majority of the synthesized silicon nanowires exhibit the expected diamond cubic crystalline structure. About 75% of the diamond cubic silicon nanowires synthesized grow in a single <111> direction, while the rest contain growth-related kinks, where the nanowire switches to another direction during the growth. The ~109° silicon nanowire kinks are the most commonly observed, and the growth direction before and after such ~109° kink are both <111>. The sidewalls of silicon nanowires do not change abruptly at the ~109° kink, but exhibit an elbow-shaped structure. It is also found that the nanowire sidewalls exhibit periodic nanofaceting, which is strongly doping-dependent. The nanofaceting is found to occur during the enhanced sidewall growth that arises when the diborane dopant gas is introduced. A thermodynamic model predicting the dependence of nanofacet period on the wire diameter is developed. Another semiconductor nanostructure studied in this thesis is indium nitride colloidal nanoparticles, which were grown using a solution-phase chemical method. The formation of such indium nitride colloidal nanoparticles is confirmed by studying their compositions, crystalline structures and shape using various electron microscopy techniques. The size of the indium nitride colloidal nanoparticles was controlled by varying the time of solution-phase reactions. The most probable size of the colloidal nanoparticles increases and the size distribution broadens with the increase of reaction time. The crystalline structures of the indium nitride colloidal nanoparticles are found to be particle size dependent. The observed dependence of the band gap blueshift of the indium nitride colloidal nanoparticles on the reaction time (hence the particle size) is explained by the quantum-size effect.

O Complexo Morro Redondo, com cerca de 250 Km2, é uma das ocorrências mais importantes de granitos de tipo-A da Província Graciosa, uma importante província póscolisional neoproterozóica (ca. 580 Ma) na região sul-sudeste do Brasil. O Complexo aflora nas proximidades de Tijucas do Sul (PR) e Garuva (SC). É formado pelos Plútons Papanduva e Quiriri, em que afloram, respectivamente, rochas graníticas das associações alcalina e aluminosa de granitos de tipo-A, respectivamente; e por rochas vulcânicas ácidas e básico-intermediárias contemporâneas. O Plúton Papanduva, objeto deste trabalho, aflora na porção norte do Complexo, estendendo-se por uma área de cerca de 100 Km2. Constitui-se essencialmente de álcalifeldspato granitos hipersolvus leucocráticos a hololeucocráticos, de granulação média a fina. De acordo com suas estrutruras, texturas e mineralogia, foram individualizadas quatro unidades distintas, denominadas informalmente de A, B, C e D. As Unidades A e B afloram junto às bordas NE e N do plúton, e nas proximidades de zonas de cisalhamento mais importantes. São caracterizadas por teores modais moderados a altos de quartzo (50-60 % modal) e por texturas deformacionais desde cataclásticas (Unidade B) até protomiloníticas (Unidade A), resultantes de eventos deformacionais tardi a pós-magmáticos. A Unidade C apresenta a maior expressão geográfica, aflorando nas zonas centrais e SW do plúton. Agrupa rochas de estrutura essencialmente maciça, com teores de quartzo mais baixos (próximos de 20% modal). A Unidade D compreende diques centimétricos a decamétricos de álcali-feldspato microgranitos interpretados como o último evento magmático. O feldspato alcalino varia de mesopertítico a pertítico, sendo relativamente mais potássico nas rochas mais deformadas das Unidades A e B. Laths de albita quase pura ocorrem em interscrescimentos com anfibólio e clinopiroxênios sódicos e alguns minerais acessórios, sugerindo coprecipitação em estágios tardi(?) ? a pós-magmáticos. As paragêneses máficas compreendem anfibólios magmáticos e clinopiroxênios tardi- a pósmagmáticos, variando desde tipos sódico-cálcicos (Fe-richterita e egirina-augita) até sódicos (arfvedsonita/riebeckita e egirina). Iniciam sua cristalização posteriormente às fases félsicas, o que caracteriza uma ?seqüência agpaítica de cristalização?. A variação composicional dos anfibólios acompanha, aproximadamente, o aumento da abundância modal de quartzo e/ou a presença de feições indicativas de deformação (cataclasitos) com os termos mais cálcicos aparecendo nas amostras com menores teores de quartzo e estruturas maciças (Unidade C). Na arfvedsonita e egirina as trajetórias evolutivas são marcadas pelo aumento de Na e Fe3+ paralelo à diminuição de Ca, Fe2+ e Ti em direção às bordas cristalinas, indicando condições progressivamente mais alcalinas e oxidantes. Riebeckita é pós-magmática, aparecendo tipicamente em amostras com indícios de alteração hidrotermal das Unidades B e D. Ilmenita ocorre ocasionalmente nas Unidades B, C e D, enquanto magnetita é rara, tipicamente pós-magmática, resultando em valores muito baixos de susceptibilidade magnética (< 1,0 x 10-3 SI). Zircão, chevkinita e astrofilita são os acessórios mais típicos nas Unidades B, C. Por outro lado, uma variedade de minerais acessórios raros, de cristalização tardi ? a pósmagmática, típicos de rochas peralcalinas, como narsarsukita, neptunita (portadores de Ti); britholita e nacareniobsita (portadores de ETR); além de zirconossilicatos de (Na, K), turkestanita e bastnäsita ocorre tipicamente em amostras mais deformadas da Unidade A. A associação aparentemente contemporânea das rochas graníticas com um vulcanismo de caráter bi-modal, a observação de cavidades miarolíticas, bolsões pegmatíticos e texturas gráficas e semi-gráficas no Plúton Papanduva indica condições crustais relativamente rasas para a colocação do magmatismo granítico. Com base nos equilíbrios minerais observados e na presença/ausência de certas fases minerais, pode-se estimar trajetórias evolutivas de T e ?O2 durante a seqüência de cristalização do Plúton Papanduva. As trajetórias são governadas, durante os estágios magmáticos, pela diminuição de T (ca. 750 ? 500o C), em condições progressivamente mais oxidantes, com ?O2 variando desde valores equivalentes ao tampão WM (magnetita ? wüstita) até valores próximos àqueles definidos pelo tampão HM (hematita ? magnetita). A concentração de álcalis, voláteis, HFSE (Zr, Ti, Nb, ETR) e ocasionalmente Ca nos líquidos residuais decorrentes da evolução dos magmas peralcalinos e, em parte, devido à entrada de fluidos externos (Ca e H2O) permitiu a cristalização de minerais acessórios raros. A presença desses acessórios nas rochas tipicamente deformadas sugere que a deformação teve um papel importante na remobilização e circulação desses elementos nos estágios tardi- a pósmagmáticos. / The Morro Redondo Complex, covering an area of about 250 km2, is one of the most expressive occurrences of granites and associated bimodal volcanic rocks from the Neoproterozoic (ca. 580 Ma), post-collisional, A-type Graciosa Province in south-southeast Brazil. The Complex outcrops near Tijucas do Sul (PR) and Garuva (SC) townships, and consists of two main intrusive units: the Papanduva and Quiriri Plutons, both comprising granitic rocks from the alkaline and aluminous petrographic associations of A-type granites. The Papanduva Pluton, which is the main subject of this work, comprises the northern portion of the Morro Redondo Complex, covering an area of about 100 Km2. It is made up of leucocratic to hololeucocratic, coarse- to fine-grained hypersolvus alkali-feldspar granites. Based on their structures, textures and mineralogy, four distinct units were recognized and informally named A, B, C and D. Units A and B outcrops near the NE and N borders of the pluton, and close to major shear zones. They are characterized by high modal quartz contents (50-60 %) and deformational textures varying from cataclastic (Unit B) to protomylonitic (Unit A), as the result of late- to post-magmatic tectonic stress. Unit C, the largest in extent, occurs in the central and SW parts of the pluton. It consists of massive granitic rocks, with lower modal quartz content (ca. 20%). Unit D comprises alkali-feldspar microgranites interpreted as formed by the latest magmatic event. Alkali feldspar varies from mesoperthic to perthitic, being relatively more potassic in the deformed rocks from Units A and B. In some rocks idiomorphic laths of almost pure albite are found in intergrowths with interstitial pyroxene, amphiboles, and accessory minerals; suggesting co-precipitation in the late(?)- to post-magmatic stage. The mafic paragenesis includes magmatic amphiboles and late- to post-magmatic clinopyroxenes, varying from sodic-calcic (Fe-richterite and aegirine-augite) to sodic varieties (arfvedsonite/riebeckite and aegirine). The crystallization history of mafic minerals starts after the felsic phases, in a typical ?agpaitic crystallization sequence?. The amphibole and clinopyroxene compositional variations follow the increase in quartz modal content and/or the presence of deformational textures, with the more calcic varieties crystallizing in rocks with low modal quartz contents and massive structure (Unit C). For arfvedsonite and aegirine, the evolutional trends are marked by enrichment in Na and Fe3+ and depletion in Ca, Fe2+ and Ti towards crystal rims, suggesting progressively more oxidizing and alkaline conditions. Riebeckite is in a post-magmatic phase in hydrothermally altered rocks from Units B and D. Ilmenite appears occasionally in Units B, C and D, while magnetite is a rare phase, typically post-magmatic; thus, the magnetic susceptibility values are very low for most rocks (< 1.0 x 10-3 SI). Zircon, chevkinite and astrophyllite are the most typical accessories in Units B and C. On the other hand, a variety of late- to post-magmatic rare accessory minerals, typical of peralkaline rocks, such as narsarsukite, astrophyllite and neptunite (Ti-bearing); britholite and nacareniobsite (REE-bearing); as well as ( Na, K) zirconosilicates, turkestanite and bastnäsite, appears in the more deformed samples from Unit A. The apparently contemporary association of granitic and bi-modal volcanic rocks, the presence of miarolitic cavities, pegmatitic veins and graphic and semigraphic textures in the Papanduva Pluton indicate emplacement at a relatively high crustal level. Based on the observed mineral equilibria and the presence or absence of some mineral phases it was possible to establish evolutional trends in T-?O2 space during the crystallization sequence of rocks from Papanduva Pluton. The trajectories are governed, during the magmatic stages, by falling temperature (ca. 750 ? 500o C) in progressively more oxidizing environments, with ?O2 varying from MW (magnetite-wüstite) to HM (hematite-magnetite) buffer conditions. The concentration of alkalis, volatiles , HFSE (Zr, Ti, Nb, REE) and occasionally Ca in the residual liquids, as a consequence of peralkaline magma evolution, or, in part, due to external fluids (Ca and H2O) led to the crystallization of rare accessory mineral phases. The presence of these accessory minerals in typically deformed rocks suggests that deformational events played an important role in the remobilization and circulation of these elements in the late- to post-magmatic stages.

O Complexo Morro Redondo, com cerca de 250 Km2, é uma das ocorrências mais importantes de granitos de tipo-A da Província Graciosa, uma importante província póscolisional neoproterozóica (ca. 580 Ma) na região sul-sudeste do Brasil. O Complexo aflora nas proximidades de Tijucas do Sul (PR) e Garuva (SC). É formado pelos Plútons Papanduva e Quiriri, em que afloram, respectivamente, rochas graníticas das associações alcalina e aluminosa de granitos de tipo-A, respectivamente; e por rochas vulcânicas ácidas e básico-intermediárias contemporâneas. O Plúton Papanduva, objeto deste trabalho, aflora na porção norte do Complexo, estendendo-se por uma área de cerca de 100 Km2. Constitui-se essencialmente de álcalifeldspato granitos hipersolvus leucocráticos a hololeucocráticos, de granulação média a fina. De acordo com suas estrutruras, texturas e mineralogia, foram individualizadas quatro unidades distintas, denominadas informalmente de A, B, C e D. As Unidades A e B afloram junto às bordas NE e N do plúton, e nas proximidades de zonas de cisalhamento mais importantes. São caracterizadas por teores modais moderados a altos de quartzo (50-60 % modal) e por texturas deformacionais desde cataclásticas (Unidade B) até protomiloníticas (Unidade A), resultantes de eventos deformacionais tardi a pós-magmáticos. A Unidade C apresenta a maior expressão geográfica, aflorando nas zonas centrais e SW do plúton. Agrupa rochas de estrutura essencialmente maciça, com teores de quartzo mais baixos (próximos de 20% modal). A Unidade D compreende diques centimétricos a decamétricos de álcali-feldspato microgranitos interpretados como o último evento magmático. O feldspato alcalino varia de mesopertítico a pertítico, sendo relativamente mais potássico nas rochas mais deformadas das Unidades A e B. Laths de albita quase pura ocorrem em interscrescimentos com anfibólio e clinopiroxênios sódicos e alguns minerais acessórios, sugerindo coprecipitação em estágios tardi(?) ? a pós-magmáticos. As paragêneses máficas compreendem anfibólios magmáticos e clinopiroxênios tardi- a pósmagmáticos, variando desde tipos sódico-cálcicos (Fe-richterita e egirina-augita) até sódicos (arfvedsonita/riebeckita e egirina). Iniciam sua cristalização posteriormente às fases félsicas, o que caracteriza uma ?seqüência agpaítica de cristalização?. A variação composicional dos anfibólios acompanha, aproximadamente, o aumento da abundância modal de quartzo e/ou a presença de feições indicativas de deformação (cataclasitos) com os termos mais cálcicos aparecendo nas amostras com menores teores de quartzo e estruturas maciças (Unidade C). Na arfvedsonita e egirina as trajetórias evolutivas são marcadas pelo aumento de Na e Fe3+ paralelo à diminuição de Ca, Fe2+ e Ti em direção às bordas cristalinas, indicando condições progressivamente mais alcalinas e oxidantes. Riebeckita é pós-magmática, aparecendo tipicamente em amostras com indícios de alteração hidrotermal das Unidades B e D. Ilmenita ocorre ocasionalmente nas Unidades B, C e D, enquanto magnetita é rara, tipicamente pós-magmática, resultando em valores muito baixos de susceptibilidade magnética (< 1,0 x 10-3 SI). Zircão, chevkinita e astrofilita são os acessórios mais típicos nas Unidades B, C. Por outro lado, uma variedade de minerais acessórios raros, de cristalização tardi ? a pósmagmática, típicos de rochas peralcalinas, como narsarsukita, neptunita (portadores de Ti); britholita e nacareniobsita (portadores de ETR); além de zirconossilicatos de (Na, K), turkestanita e bastnäsita ocorre tipicamente em amostras mais deformadas da Unidade A. A associação aparentemente contemporânea das rochas graníticas com um vulcanismo de caráter bi-modal, a observação de cavidades miarolíticas, bolsões pegmatíticos e texturas gráficas e semi-gráficas no Plúton Papanduva indica condições crustais relativamente rasas para a colocação do magmatismo granítico. Com base nos equilíbrios minerais observados e na presença/ausência de certas fases minerais, pode-se estimar trajetórias evolutivas de T e ?O2 durante a seqüência de cristalização do Plúton Papanduva. As trajetórias são governadas, durante os estágios magmáticos, pela diminuição de T (ca. 750 ? 500o C), em condições progressivamente mais oxidantes, com ?O2 variando desde valores equivalentes ao tampão WM (magnetita ? wüstita) até valores próximos àqueles definidos pelo tampão HM (hematita ? magnetita). A concentração de álcalis, voláteis, HFSE (Zr, Ti, Nb, ETR) e ocasionalmente Ca nos líquidos residuais decorrentes da evolução dos magmas peralcalinos e, em parte, devido à entrada de fluidos externos (Ca e H2O) permitiu a cristalização de minerais acessórios raros. A presença desses acessórios nas rochas tipicamente deformadas sugere que a deformação teve um papel importante na remobilização e circulação desses elementos nos estágios tardi- a pósmagmáticos. / The Morro Redondo Complex, covering an area of about 250 km2, is one of the most expressive occurrences of granites and associated bimodal volcanic rocks from the Neoproterozoic (ca. 580 Ma), post-collisional, A-type Graciosa Province in south-southeast Brazil. The Complex outcrops near Tijucas do Sul (PR) and Garuva (SC) townships, and consists of two main intrusive units: the Papanduva and Quiriri Plutons, both comprising granitic rocks from the alkaline and aluminous petrographic associations of A-type granites. The Papanduva Pluton, which is the main subject of this work, comprises the northern portion of the Morro Redondo Complex, covering an area of about 100 Km2. It is made up of leucocratic to hololeucocratic, coarse- to fine-grained hypersolvus alkali-feldspar granites. Based on their structures, textures and mineralogy, four distinct units were recognized and informally named A, B, C and D. Units A and B outcrops near the NE and N borders of the pluton, and close to major shear zones. They are characterized by high modal quartz contents (50-60 %) and deformational textures varying from cataclastic (Unit B) to protomylonitic (Unit A), as the result of late- to post-magmatic tectonic stress. Unit C, the largest in extent, occurs in the central and SW parts of the pluton. It consists of massive granitic rocks, with lower modal quartz content (ca. 20%). Unit D comprises alkali-feldspar microgranites interpreted as formed by the latest magmatic event. Alkali feldspar varies from mesoperthic to perthitic, being relatively more potassic in the deformed rocks from Units A and B. In some rocks idiomorphic laths of almost pure albite are found in intergrowths with interstitial pyroxene, amphiboles, and accessory minerals; suggesting co-precipitation in the late(?)- to post-magmatic stage. The mafic paragenesis includes magmatic amphiboles and late- to post-magmatic clinopyroxenes, varying from sodic-calcic (Fe-richterite and aegirine-augite) to sodic varieties (arfvedsonite/riebeckite and aegirine). The crystallization history of mafic minerals starts after the felsic phases, in a typical ?agpaitic crystallization sequence?. The amphibole and clinopyroxene compositional variations follow the increase in quartz modal content and/or the presence of deformational textures, with the more calcic varieties crystallizing in rocks with low modal quartz contents and massive structure (Unit C). For arfvedsonite and aegirine, the evolutional trends are marked by enrichment in Na and Fe3+ and depletion in Ca, Fe2+ and Ti towards crystal rims, suggesting progressively more oxidizing and alkaline conditions. Riebeckite is in a post-magmatic phase in hydrothermally altered rocks from Units B and D. Ilmenite appears occasionally in Units B, C and D, while magnetite is a rare phase, typically post-magmatic; thus, the magnetic susceptibility values are very low for most rocks (< 1.0 x 10-3 SI). Zircon, chevkinite and astrophyllite are the most typical accessories in Units B and C. On the other hand, a variety of late- to post-magmatic rare accessory minerals, typical of peralkaline rocks, such as narsarsukite, astrophyllite and neptunite (Ti-bearing); britholite and nacareniobsite (REE-bearing); as well as ( Na, K) zirconosilicates, turkestanite and bastnäsite, appears in the more deformed samples from Unit A. The apparently contemporary association of granitic and bi-modal volcanic rocks, the presence of miarolitic cavities, pegmatitic veins and graphic and semigraphic textures in the Papanduva Pluton indicate emplacement at a relatively high crustal level. Based on the observed mineral equilibria and the presence or absence of some mineral phases it was possible to establish evolutional trends in T-?O2 space during the crystallization sequence of rocks from Papanduva Pluton. The trajectories are governed, during the magmatic stages, by falling temperature (ca. 750 ? 500o C) in progressively more oxidizing environments, with ?O2 varying from MW (magnetite-wüstite) to HM (hematite-magnetite) buffer conditions. The concentration of alkalis, volatiles , HFSE (Zr, Ti, Nb, REE) and occasionally Ca in the residual liquids, as a consequence of peralkaline magma evolution, or, in part, due to external fluids (Ca and H2O) led to the crystallization of rare accessory mineral phases. The presence of these accessory minerals in typically deformed rocks suggests that deformational events played an important role in the remobilization and circulation of these elements in the late- to post-magmatic stages.

The Coeur d'Alene district in northern Idaho is a world class Pb-Ag mesothermal vein system that has produced about 360 million ounces of silver, lead, and zinc since the 1880s. Despite the long history of exploration and production, the district does not have a predictive model for exploration based on a sound understanding of structural controls on the silver ore deposits; this is certainly the case for the Sunshine Mine and surrounding area. Fault kinematic history in the district shows a regional scale fault system reactivated over time with dextral, sinistral, and dip-slip displacement. The fault system is superimposed on regional deformation fabrics that were examined for this study in the Sunshine Mine area. Cleavage sets observed in the Sunshine mine area, distinguished by orientation and superposition relationships, are consistent with the findings of Smith (2004) which defined cleavage sets referred to as S1, S2, and S3. Two additional deformation fabrics that appear spatially tied to fault zones formed between development of cleavages S2 and S3. The multiple cleavages, fault zones, and their intersections are interpreted to act as pathways for hydrothermal fluids associated with vein formation and silver ore deposition. Thin section kinematic analysis of vein and shear zone samples defined a dip-slip sense of shear associated with the Sterling vein. Electron Backscatter Diffraction (EBSD) analysis of vein and shear zone samples failed to define a lattice preferred crystallographic orientation that defined shear sense. Similarly, cathodoluminescence (CL) analysis of thin section textures failed to define a dominant shear sense and fault kinematics. Nevertheless, additional study using these techniques is warranted. Both field observation and thin section analysis demonstrate a direct relationship between shear zones, veins, and mineralization potential, clarifying the need for detailed fault maps for the Sunshine Mine area and Coeur d'Alene district.

One taphonomic problem plaguing archaeologists and physical anthropologists, whether their research is in North American cultures or hominid sites in Africa, is the difficulty in distinguishing bone altered by burning and heating from bone altered by soil processes. Archaeologists working to understand the recent prehistory of the Southern Oregon Coast face the same challenge. Two relatively new tools were investigated to determine their usefulness to resolving this problem. These are scanning electron microscopy (SEM) and X-ray diffraction (XRD). SEM has been well-tested in African sites and experimental studies to identify hominid-created cut marks on bone and to reconstruct heating temperatures of burnt bone. However, SEM and its ability to sample chemistry, as well as XRD's ability to detect diagentic alteration in bone minerals, have not been tested on material from coastal Oregon. The purpose of this research was: (1) to test these methods to see whether they could distinguish between burning and soil alteration, using cervid bone from site 35CS43 near Bandon, Ore., as a test sample, and (2) to see whether the result, paired with archaeological, ethnographic, taphonomic and faunal evidence, could be used to understand how the Coquille were procuring, processing and cooking cervids as insights into their adaptation. The outcome suggests that SEM and XRD, without use of other evidence, are unable to distinguish between burning and soil alteration because the similarities between the two lie not only in changes to the bone's macrostructure (discoloration) but also in bone chemistry, where it was hoped differences could be found. However, these techniques, when paired with the other lines of evidence, did provide insights in understanding the taphonomy and the Coquille's use of cervids - the interaction of bone and soil; the extent of mimicry between burning and soil alteration; and ultimately that discoloration of cervid bone at 35CS43 was likely due to soil alteration, that burning as the result of fire roasting was most likely not occurring at the site, and that the Coquille employed other methods of cooking. / Graduation date: 2003

Cystic fibrosis (CF) is an inherited disease with symptoms mainly in the respiratory tract. The airway epithelium is covered with a thin layer of fluid, the airway surface liquid (ASL). The volume and composition of ASL are important in the pathogenesis of cystic fibrosis. The composition of ASL was determined. Firstly, pig airways were analyzed by X-ray microanalysis in the frozen-hydrated state. Secondly, small Sephadex beads were left to absorb the ASL in situ and were analyzed by X-ray microanalysis. The Na and Cl concentrations in the ASL of the pig were close to those of these ions in serum. Rat tracheal ASL was hypotonic. However, rat nasal fluid was hypertonic with an extremely high concentration of K. The composition of the ASL could be influenced by pharmacological stimulation. The development of transgenic mouse models for CF may help to develop therapies for the disease. The composition of mouse ASL was investigated using different collection techniques. (1) beads mounted on filter paper, (2) beads randomly spread over the airway epithelium, and (3) beads spread over the epithelium with a syringe. No significant difference could be detected between these techniques, and mouse ASL was hypotonic. Calibration curves had to be made for each element of interest. Nasal fluid from healthy human volunteers was collected with: (1) a pipette, (2) filter paper, (3) cotton wool, or (4) Sephadex beads. Collection on filter paper and equilibration with Sephadex beads gave reliable results. The Na and Cl concentrations in nasal fluid of control subjects were about the same as in serum, but the K concentration was higher. Rhinitis or primary ciliary dyskinesia patients and CF heterozygotes had abnormally high concentrations of Na and Cl in their nasal fluid (probably due to inflammation of the nasal epithelium), and CF homozygotes had even higher concentrations of Na and Cl.