Thesis (B.S.)--University of Wisconsin -- La Crosse, 2008. / Also available online. Includes bibliographical references (leaves 29-31).

<p> Promoted and supported catalysts were studied with an electron probe microanalyzer. Investigations we re made on promoted fused iron ammonia synthesis catalysts regardirlg the general morphology of the catalysts, the distribution of promoters, and the reduction and poisoning processes . The effect of the promoters on the reduction process , the effect of the impurity silica on the promoter distributions and the nature of the poisoning are discussed. Supported catalysts were prepared by impregnating porous y-alumina spheres with solutions of chromium and/or copper compounds. Concentration profiles for chromium and/or copper , i.e., concentration as a function of distance from the center, were determined on sectioned spheres. Different distributions of these elements on the alumina support were obtained by varying the chemical used, the concentration and the amount of the solution impregnated. Explanations are given for the physical and chemical processes involved during the impregnation . The amount of chromium or copper impregnated is compared with the amount present in each particle. </p> / Thesis / Doctor of Philosophy (PhD)

第22回名古屋大学年代測定総合研究センターシンポジウム平成21(2009)年度報告

Zircon from the zircon concentrate of Richards Bay Minerals was investigated with a view to understanding the morphology and provenance. The obsevations were applied to the reduction of uranium, thorium and other trace elements in the heavy mineral placer deposits. It is evident from differences in morphology, optical characteristics, cathodoluminescence, inclusion types and trace element analyses that the zircon is derived from numerous parent rocks. Rare earth element modelling reveals several possible parent rocks including rhyolites, granites, syenites, pegmatites and carbonatites. Fission track U mapping of individual zircons indicated an enrichment of U in the rims and grain terminations. The U maps were used to devise and test several methods, including abrasion and partial dissolution, to reduce the combined U and Th concentration from 450-563ppm to below 400ppm. The effect of magnetic cleaning, density separation and size classification of the zircon concentrate on the U +Th concentration was found to be negligible. Air abrasion and HF acid dissolution successfully reduced the U +Th concentrations to between 332 and 383ppm. The contribution of trace elements from inclusions, surface pit fillings and coatings, and foreign minerals within the zircon concentrate were evaluated by by scanning electron microscope identification. / Thesis (M.Sc.)-University of Natal, Durban, 1992.

Evidence of mineral disequilibrium is presented for the Merensky Reef at Winnaarshoek in the eastern Bushveld Complex. Petrographic disequilibrium textures, disequilibrium in orthopyroxene, plagioclase and clinopyroxene mineral compositions as well as disequilibrium in Sm-Nd isotopic compositions of whole rock samples and coexisting plagioclase and orthopyroxene are presented. Disequilibrium textures presented include clinopyroxene exsolution lamellae in orthopyroxene; resorbed plagioclase in orthopyroxene or relict plagioclase; various inclusions such as orthopyroxene, plagioclase or clinopyroxene in larger oikocrysts of clinopyroxene or orthopyroxene; discontinuous rims of clinopyroxene surrounding orthopyroxene; resorbed orthopyroxene in clinopyroxene; and corona textures associated with olivine. These textures were used to derive a possible mineral crystallization sequence. At least two sequences of crystallization took place, both of which crystallized plagioclase first. One sequence then crystallized olivine which was then consumed to produce orthopyroxene which crystallized prior to late clinopyroxene. The other sequence indicates orthopyroxene crystallization after plagioclase crystallization, followed by crystallization of clinopyroxene. These sequences indicate at least two magmas were responsible for the genesis of the Merensky Reef and its hanging wall and footwall units. Compositionally, disequilibrium is evident in the range of compositions found in coexisting orthopyroxene, plagioclase and clinopyroxene with stratigraphic height, with particular reference to the change in mineral composition in each of the hanging wall, Reef and footwall units. Orthopyroxene compositions range in Mg numbers between 74.6 and 82.9 (77.4) in the hanging wall, 78.5 and 87.0 (avg. 81.1) in the Reef, and 77.9 and 84.1 (avg. 81.3) in the footwall. Plagioclase compositions range in An content between An64.9 and An82.3 (avg. An75.1) in the hanging wall, An56.8 to An70.8 (avg. An62.7) in the Reef, and An54.2 to An86.3 (avg. An73.2) in the footwall. In terms of Sm-Nd isotopic compositions, disequilibrium is evident between both whole rock samples and coexisting plagioclase and orthopyroxenes. Bulk rock Sm-Nd isotopic compositions show a range in ԐNd values between ԐNd (2.06 Ga) = -4.8 to -6.4 in the hangingwall, ԐNd (2.06 Ga) = -6.3 to -8.5 in the Reef, and ԐNd (2.06 Ga) = -4.5 to -6.3 in the footwall. Similar ԐNd values are present in the hanging wall and footwall units, with a clear “spike” in the Merensky Reef. ԐNd values in plagioclase are between ԐNd (2.06 Ga) = -5.8 and -7.8, while orthopyroxene isotopic Sm-Nd values are between ԐNd (2.06 Ga = -7.1 and -9.1. The mineral disequilibrium features presented within this study help elucidate the crystallization sequence of the magma as well as to constrain the contamination of the magma upon ascension and emplacement of the Merensky Reef. The results of this study favour a model where a mantle plume resulted in the ascent of a new magma which was contaminated by the assimilation of old, lower crust. Contamination took place prior to the possible lateral emplacement of the Merensky reef as a density current. 5-10% contamination of depleted mantle or a B2-“like” source by Archaean TTGs is modeled to achieve the contamination “spike” of ԐNd = -8.5 in the Merensky Reef.

The samples of garnets used in this study come from clastic sediments from the drillcores Tř-1 and T-31, selected localities of the České středohoří Mountains and garnet-bearing ultramafic rocks sampled by the drillcore T-7. The contents of the major and some minor elements were determined by an electron probe microanalyzer. The garnets from the sediments were divided into 3 groups according to the contents of the end-members: 1) pyrope-, 2) almandine - pyrope- and 3) grosular - almandine-rich. Garnets from the drillcore T-7 were classified according to individual rock types in which they occurred: lherzolite, hazburgite, pyroxenite, eclogite and granulite. Chemical analyzes of garnets displayed the presence of positive correlations Cr vs. Ca vs. Ti Mn in pyrope grains. The contents of trace elements in garnets were studied by an LA-ICP-MS. After normalization to the CI-reservoir, garnets most often show lherzolite profiles of rare earth elements. Garnets of intense red and purple colors show slightly sinusoidal REE profiles. Inclusions enclosed in garnets were studied by a scanning electron microscope. If their dimensions allowed, the major and minor elements were determined by electron microanalysis for inclusions. Inclusions of amphiboles in association with spinel group minerals, carbonates and...

The samples of garnets used in this study come from clastic sediments from the drillcores Tř-1 and T-31, selected localities of the České středohoří Mountains and garnet-bearing ultramafic rocks sampled by the drillcore T-7. The contents of the major and some minor elements were determined by an electron probe microanalyzer. The garnets from the sediments were divided into 3 groups according to the contents of the end-members: 1) pyrope-, 2) almandine - pyrope- and 3) grosular - almandine-rich. Garnets from the drillcore T-7 were classified according to individual rock types in which they occurred: lherzolite, hazburgite, pyroxenite, eclogite and granulite. Chemical analyzes of garnets displayed the presence of positive correlations Cr vs. Ca vs. Ti Mn in pyrope grains. The contents of trace elements in garnets were studied by an LA-ICP-MS. After normalization to the CI-reservoir, garnets most often show lherzolite profiles of rare earth elements. Garnets of intense red and purple colors show slightly sinusoidal REE profiles. Inclusions enclosed in garnets were studied by a scanning electron microscope. If their dimensions allowed, the major and minor elements were determined by electron microanalysis for inclusions. Inclusions of amphiboles in association with spinel group minerals, carbonates and...

Inconel 718 is a high nickel content superalloy possessing high strength at elevated temperatures and resistance to oxidation and corrosion. The non-traditional manufacturing process of wire-electrical discharge machining (EDM) possesses many advantages over traditional machining during the manufacture of Inconel 718 parts. However, certain detrimental effects are also present. The top layer of the machined surface is melted and resolidified to form what is known as the recast layer. This layer demonstrates microstructural differences from the bulk workpiece, resulting in altered material properties. An experimental investigation was conducted to determine the main machining parameters which contribute to recast layer formation in wire-EDM of Inconel 718. It was found that average recast layer thickness increased with energy per spark, peak discharge current, current pulse duration, and open-voltage time and decreased with sparking frequency and table feed rate. Over the range of parameters tested, the recast layer was observed to be between 5 and 10 μm in average thickness, although highly variable in nature. Surface roughness of the cut parts showed an increase with energy per spark. Electron Probe Microanalysis (EPMA) revealed the recast layer to be alloyed with elements from the wire electrode. X-ray diffraction testing showed the residual tensile stresses evident near the cut surface to decrease with energy per spark. Additionally, nano-indentation hardness testing indicated that the recast layer is reduced in hardness and elastic modulus compared to the bulk material. Vibratory tumbling was found to be a moderately effective post-processing tool for recast layer removal when using pre-formed ceramic abrasive media or fine grained aluminum oxide.

Abstract This study utilized normal and defective epithelial cell cultures and epidermal skin samples to examine intra- and intercellular calcium signaling. The main interests of this thesis were Hailey-Hailey disease (HHD), Darier disease (DD), neurofibromatosis 1 (NF1) and transitional cell carcinoma (TCC). HHD and DD diseases are rare autosomal dominant skin disorders characterized by dissociation of epidermal keratinocytes (acantholysis) at the suprabasal layer of the epidermis. HHD and DD diseases are caused by mutations in the genes encoding the calcium pumps in the Golgi apparatus (hSPCA1) and endoplasmic reticulum (SERCA2b), respectively. Due to these mutations calcium uptake into the Golgi apparatus or ER is diminished, which is believed to cause abnormal cell junction protein processing and dissociation of keratinocytes. This study utilized electron probe microanalysis (EPMA) and demonstrated for the first time that lesional areas of HHD and DD and non-lesional areas of DD epidermis display abnormally low calcium content in the basal cell layer. Furthermore, ATP mediated calcium signaling was impaired in cultured HHD and DD keratinocytes and epidermal ATP receptor localization was disrupted. In conclusion, these results suggest that the low calcium content in the basal cell layer is the reason for suprabasal ruptures in HHD but not necessarily in DD lesions, and that abnormal ATP receptor localization contributes to the calcium signaling defects. NF1 deficient keratinocytes display abnormally low resting cytosolic calcium levels and it has been suggested that the calcium concentration in the lumen of the endoplasmic reticulum is decreased. This study demonstrated that NF1 keratinocytes rely mostly on ATP mediated calcium signaling while normal keratinocytes rely mostly on gap junctional intercellular communication (GJIC). Studies with TCC cells have demonstrated that gap junctions participate in intercellular calcium wave propagation. This thesis demonstrated that the ATP mediated pathway was also operational in calcium wave propagation in normal uroepithelial and TCC cell cultures. Furthermore, impaired calcium wave propagation in the TCC cell culture could be improved through PKC α/βI –isoenzyme inhibition with Gö6976. Gö6976 treatment increased connexin 26 clustering at plasma membrane but did not alter expression level of the protein. This thesis contains a wide repertoire of calcium detection techniques including a new cutting-edge technology for elemental calcium detection of epidermal samples. These techniques can be used for molecular specific analysis of calcium signaling in epithelial cells.

The escalating demand for metals driven by advancements in renewable energy technologies and hightech products has underscored the significance of understanding and characterizing ore deposits. This study focuses on the Ertelien Ni-Cu deposit in Norway, a region rich in nickel, cobalt, and copper resources—essential components for the transition to a sustainable energy future. The deposit, located within the Kongsberg belt, holds substantial economic potential due to its Ni-Cu-Co sulfide mineral enrichment. Previous assay results from drill cores, optical microscopy, and electron probe micro-analysis were employed to characterize the mineralogy and based on this interpreter the formation mechanisms, and enrichment processes that formed the deposit.  The Ertelien deposit represents an igneous origin with significant Ni-Cu-Co content estimated at 2.7 million metric tons, with grades of 0.83%, 0.69%, and 0.06%, respectively, within a gabbronorite intrusive body. Optical microscopy and electron probe micro-analysis revealed a complex mineral assemblage including common silicates such as plagioclase, pyroxene, amphibole, mica, olivine, and others, as well as sulfides such as pyrite, chalcopyrite, pyrrhotite, pentlandite.  The primary objective of this study is to conduct an in-depth examination of the geological, mineralogical, and enrichment aspects of the Ertelien deposit. Specifically, primary magmatic and assimilation processes involved in the formation of Ni-Cu-deposits were be evaluated, as well as any potential metal redistribution resulting from secondary processes. Mineralogical studies, facilitated by combining optical microscopy and electron microprobe analysis provided important information on the mechanisms contributing to metal enrichment in or deposits. Optical microscopy and electron probe microanalysis revealed a complex mineral assemblage including common silicates such as plagioclase, pyroxene, amphibole, mica, olivine, and others, as well as sulfides such as pyrite, chalcopyrite, pyrrhotite, pentlandite.  The analyzed rock suite spans a range of compositions from gabbroic to tonalite, with MgO concentrations varying from 0.38 to 22.96 wt.%. Overall, there is a discernible trend of sulfur enrichment in or near samples characterized by low MgO and high Na2O and CaO contents, suggesting that sulfide saturation is likely associated with the assimilation of S-bearing gneisses into which the Ertelien gabbronorites intruded. Ni concentrations exhibit an increasing trend with depth. The nickel-to-cobalt ratio (Ni/Co) displays a discernible pattern that correlates with sulfide crystallization during the process of magmatic fractionation. Notable distinctions observed among groups characterized by differing Ni/Co contents in chalcopyrite, pentlandite, pyrrhotite, and pyrite reveal distinct trends in Ni concentrations. In conjunction with the presence of sphalerite and Ag-pentlandite, which are indicative of lower temperature origin compared to magmatic activity, all these observations provide compelling indications of diverse potential sources, including variations in magma compositions and the influence of hydrothermal processes.  Investigating ore formation conditions enhances the mining sector's ability to identify high-potential mineralization areas, vital for ensuring a stable supply of metals essential for renewable energy systems, electric vehicles, and advanced electronics. / Den eskalerande efterfrågan på metaller som drivs av framsteg inom förnybar energiteknik och högteknologiska produkter har understrukit betydelsen av att förstå och karakterisera malmfyndigheter. Denna studie fokuserar på Ertelien Ni-Cu-fyndigheten i Norge, en region rik på nickel-, kobolt- och kopparresurser – väsentliga komponenter för övergången till en hållbar energiframtid. Fyndigheten, som ligger inom Kongsbergsbältet, har en betydande ekonomisk potential på grund av dess Ni-Cu-Cosulfidmineralanrikning. Tidigare analysresultat från borrkärnor, optisk mikroskopi och elektronsondsmikroanalys användes för att karakterisera mineralogin och baserat på denna tolk för bildningsmekanismerna och anrikningsprocesserna som bildade fyndigheten.  Ertelien-avlagringen representerar ett magmatiskt ursprung med betydande Ni-Cu-Co-innehåll uppskattat till 2.7 miljoner ton, med halter på 0.83%, 0.69% respektive 0.06% inom en gabbronorit-intrusiv kropp. Optisk mikroskopi och elektronsondsmikroanalys avslöjade en komplex mineralsammansättning inklusive vanliga silikater som plagioklas, pyroxen, amfibol, glimmer, olivin och andra, såväl som sulfider som pyrit, kolopirit, pyrrotit, pentlandit.  Det primära syftet med denna studie är att genomföra en djupgående undersökning av de geologiska, mineralogiska och anrikningsaspekterna av Ertelienfyndigheten. Specifikt utvärderades primära magmatiska och assimileringsprocesser involverade i bildandet av Ni-Cu-avlagringar, såväl som eventuell metallomfördelning till följd av sekundära processer. Mineralogiska studier, underlättade genom att kombinera optisk mikroskopi och elektronmikrosondanalys gav viktig information om de mekanismer som bidrar till metallanrikning i eller avlagringar. Optisk mikroskopi och elektronsondsmikroanalys avslöjade en komplex mineralsammansättning inklusive vanliga silikater som plagioklas, pyroxen, amfibol, glimmer, olivin och andra, såväl som sulfider som pyrit, kolopirit, pyrrotit, pentlandit.  Den analyserade bergsviten sträcker sig över en rad kompositioner från gabbroic till tonalit, med MgOkoncentrationer som varierar från 0.38 till 22.96 viktprocent. Sammantaget finns det en urskiljbar trend av svavelanrikning i eller nära prover som kännetecknas av lågt MgO och högt Na2O- och CaO-innehåll, vilket tyder på att sulfidmättnad sannolikt är associerad med assimileringen av S-bärande gnejser i vilka Ertelien-gabbronoriterna inträngde. Ni-koncentrationer uppvisar en ökande trend med djupet. Förhållandet nickel till kobolt (Ni/Co) visar ett urskiljbart mönster som korrelerar med sulfidkristallisation under processen för magmatisk fraktionering. Anmärkningsvärda skillnader som observerats bland grupper som kännetecknas av olika Ni/Co-halter i karbonat, pentlandit, pyrrotit och pyrit avslöjar distinkta trender i Nikoncentrationer. I samband med närvaron av sfalerit och Ag-pentlandit, som indikerar lägre temperaturursprung jämfört med magmatisk aktivitet, ger alla dessa observationer övertygande indikationer på olika potentiella källor, inklusive variationer i magmasammansättningar och påverkan av hydrotermiska processer.  Att undersöka malmbildningsförhållanden förbättrar gruvsektorns förmåga att identifiera mineraliseringsområden med hög potential, avgörande för att säkerställa en stabil tillgång på metaller som är nödvändiga för förnybara energisystem, elfordon och avancerad elektronik.