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Analys av röda missfärgningar i Gåsgruvans marmor / Analysis of red discolouration found in crystalline limestone in Gåsgruvan quarryHesser, Sarina January 2020 (has links)
Detta arbetes mål har varit att hjälpa företaget SMA Mineral att utreda de rödamissfärgningar som allt oftare påträffats i deras marmor. Rapporten är högst visuellpå mikroskopisk nivå, och avhandlar vad missfärgningarna beror på. Provmaterialhar undersökts och karakteriserats mineralogiskt och geokemiskt, och typer avmissfärgningen har identifierats. Även en förklaring över de geologiska processersom ger upphov till missfärgningarna har formats. De metoder som använts underarbetet är egna undersökningar med komplement av en litteraturstudie påavhandlingar som handlar om just missfärgningar i marmor. Provmaterial harinhämtats från tre olika platser i gruvan, dessa har sågats och tvättats och några haräven slipats och polerats. Detta material har sedan använts genom hela arbetet.Optiska observationer med hjälp av binokulär har dokumenterats digitalt, detta gavinformation om att missfärgningen ligger mellan karbonatkristallerna, och sannolikthar varit av en mer löslig karaktär i ett tidigare skede. Utifrån detta kategoriserasmissfärgningen till två olika typer. Typ A förekommer som asymmetriska,koncentrerade fläckar på och mellan kristaller men till synes oregelbundet, medantyp B följer mikrofina sprickor och kan ses i bandade regelbundna formationer imaterialet. Järnrika kristaller upptäcktes i missfärgningarnas omedelbara närhet ochhär skapades hypotesen om att det är järnoxider som orsakat föroreningarna. ÄvenSEM-analyser har gjorts för att kunna identifiera den geokemiska sammansättningenav missfärgningarna. Resultaten från SEM- och XRF-analyserna bekräftade tesen, dåjärn förekom i varierande grad i samtliga analyser utom en. Dessutom hittadeshematit som i sig lämnar röda spår, samt ren rost i form av goetit. Ävenlitteraturstudien bekräftade att förekomster av järnrika mineral i marmor förr ellersenare kommer att orsaka missfärgningar. / The goal of this project has been to assist SMA mineral, a limestone producer, tofind the source of red discolourations found in their crystalline limestone. Thediscolouration has appeared on a more regular basis than before and is starting tobecome a problem for the company.This is a highly visual report focused on a microscopical level, that follows thestudy and finding of the origin of the red discolourations. Specimens from threedifferent locations in the quarry have been collected, then cut to proper sizes to fitthe needs for the scans and examinations suited for the project. Some of the sampleswere polished to fit the requirements of SEM. The material has been opticallyanalysed through a binocular microscope and documented with high resolutionimages. This was the first major breakthrough, since the discolouration showed tobe placed between the carbonate crystals, and appeared to have been more of asolution-like substance at some point. Based on the findings, the discolourationcould be categorised inte two types, type A appears as an irregular spotting oncrystal surfaces with a deeper red colour, whilst type B can be found in fine cracksin the material and follows a more regular pattern. Lots of minerals rich in ironwere also found in close proximity to the discolourations, which led to a hypothesisthat iron oxides might be the source of the problem. The thesis was confirmed bySEM- and XRF analyses of the material. Iron in different weight-percentages wasfound in all of the analyses except for one.The mineralogical and geochemical properties of the discolouration has beendefined, and the geological process that leads to the discolouration is explained.
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Oral helse i Gamle Lödöse : En osteologisk undersøkelse av det humane materialeWehmer, Kathrine January 2020 (has links)
This Master ́s thesis focused on the oral health of people who lived in Old Lödöse, Sweden during the Middle Ages. Old Lödöse is approximately 4 miles northeast of Gothenburg. The town existed between 1100 and 1646, and within it you can find St. Peder ́s church, St. Olov ́s church and a monastery. The analyzed material was from these three places and consisted of 58 individuals affected by various oral pathology. From St. Peder ́s church there were 33 individuals, from St. Olov ́s there were 4 individuals and from the monastery there were 19 individuals. They were mostly young adults (20 – 35 year) and middle age adults (35 – 50 year), and there were more men (22) than women (14) in the material. Even though there were more individuals at St. Peder ́s church, the monastery’s individuals were more severely affected by various oral pathologies, furthermore the men were more severely affected with oral pathology than the women. In addition, there were two interesting discoveries. Seven individuals, three of them women, had black discoloring on their teeth, and there were six individuals, four of them men, that had special dental wear that may reflect “teeth as tools”, some in the form of grooves. Summarized, the oral health at Old Lödöse was poor.
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