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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Johan Afzelius, professor i kemi i Uppsala : En biografi

Lindsjö, Svante January 2009 (has links)
<p>Johan Afzelius held the chair in chemistry at Uppsala University 1784-1820. His predecessor was the reputable Torbern Bergman, one of Afzelius’ students the famous Jacob Berzelius. The published scientific production of Afzelius is very limited. Afzelius has been described as with no interest of chemistry, reluctant to scientific innovations and as an opponent to the new "antiflogistic" chemistry. Also, he is believed to have given Jacob Berzelius hard times when Berzelius studied in Uppsala.</p><p>The study suggests that the judgement of Johan Afzelius should be revised. It appears that the above description of Afzelius is to be regarded as an artefact. So, Afzelius, besides being devoted to mineralogy, was keen at chemistry, interested in scientific innovations, and from 1799 on no opponent to the new chemistry.</p>
2

Johan Afzelius, professor i kemi i Uppsala : En biografi

Lindsjö, Svante January 2009 (has links)
Johan Afzelius held the chair in chemistry at Uppsala University 1784-1820. His predecessor was the reputable Torbern Bergman, one of Afzelius’ students the famous Jacob Berzelius. The published scientific production of Afzelius is very limited. Afzelius has been described as with no interest of chemistry, reluctant to scientific innovations and as an opponent to the new "antiflogistic" chemistry. Also, he is believed to have given Jacob Berzelius hard times when Berzelius studied in Uppsala. The study suggests that the judgement of Johan Afzelius should be revised. It appears that the above description of Afzelius is to be regarded as an artefact. So, Afzelius, besides being devoted to mineralogy, was keen at chemistry, interested in scientific innovations, and from 1799 on no opponent to the new chemistry.
3

Critical Assessment of the Mineralogical Collections at Uppsala University using Raman Spectroscopy / Kritisk studie av de mineralogiska samlingarna vid Uppsala universitet med hjälp av Ramanspektroskopi

Zhuk, Yuliya January 2017 (has links)
The technique of Raman spectroscopy was applied in order to identify and characterize the number of minerals in the mineralogical collection at the Department of Earth Sciences. The collection was broadened with five rare carbonates borrowed from the collection of the Swedish Museum of Natural History in Stockholm. In total, 66 specimens were examined.The characteristics of interest included possible presence and nature of defects and impurities, degree of crystallinity, residual stresses, possible treatment by natural heat sources (e.g. radionuclides) or chemicals (e.g. polishing agents), and fluorescence.Raman spectroscopy was chosen as examination method because of its distinctive advantage over traditional techniques – a non-destructive probing of pristine materials and minimum or no preparation. Besides, Raman spectroscopy performs very well in collecting the needed characteristics, in terms of its sensitivity, as well ability to probe miniature grains in a matrix with a high spatial resolution.A portable system was used to identify the presence of impurities and the fingerprint of the host rock in the majority of the examined carbonates. The rare carbonate burbankite showed distinct fluorescence bands, which likely can be explained by its complicated chemical composition.The Raman system was used for gemmological purposes and helped to identify the purity of the gems. Diamond and two rubies showed to be free from impurities, but red corundum showed a broad peak, which may represent traces of natural heat treatment, which in turn could be caused by regional metamorphism or even by a radiation source. Furthermore, the correlation between the signal intensity of the fluorites’ bands and the chemical composition of the minerals were studied. The experiment showed that blue fluorite fully misses the peak T2g while purple and grey fluorites showed a well-developed and easily recognizable peak at this location. Thus, it was discovered that the presence and intensity of this peak is directly dependent on the fluorite’s colour, i.e. on the host species, which are incorporated in the crystal structure, such as metals, rare earth elements (REE) or even organic substances. Moreover, residual tensile stress was identified in colourless quartz. The tensile stress was estimated to be in the interval between 0.23 and 1.0 GPa.The Raman system was used to identify different end-members of the garnet family. Raman spectroscopy showed to have high analytical power and helped to estimate the ratio between the end-members in eight garnet samples. In one case, fluorescence was linked to the presence of REEs in the structure of almandine. One sample of calcite showed to be incorrectly placed in the collection. This work will now form a solid foundation for the mineral characteristics handbook. / Ramanspektroskopitekniken applicerades för att identifiera och karakterisera antalet mineraler i den mineralogiska samlingen vid Institutionen för geovetenskaper. Samlingen breddades med fem sällsynta karbonater som lånades från Naturhistoriska riksmuseets samling i Stockholm. Sammanlagt analyserades 66 prover. Egenskaperna av intresse inkluderade eventuell förekomst av och karaktären hos defekter och föroreningar, graden av kristallinitet, restspänningar, eventuella spår av naturlig värmebehandling (till exempel radionuklider) eller kemisk behandling (till exempel polermedel), och fluorescens. Ramanspektroskopi valdes som undersökningsmetod på grund av dess tydliga fördel över traditionella metoder – en icke-förstörande undersökning av rena material och minimal eller ingen förberedelse. Därutöver fungerar Ramanspektroskopi väldigt bra för undersökning av de efterfrågade egenskaperna, vad gäller dess känslighet och kapacitet vid sondering av miniatyrkorn i matriser med hög spatial upplösning. Ett portabelt system användes för att identifiera föroreningar och fingeravtryck av den omslutande bergarten i de flesta undersökta karbonatprov. Den sällsynta karbonaten burbankit visade på distinkta fluorescensband, som sannolikt kan tillskrivas dess komplicerade kemiska sammansättning. Ramansystemet användes i gemmologiskt syfte och kunde identifiera ädelstenarnas renhet. Diamant och två rubiner visade sig sakna föroreningar, men den röda korunden visade en bred topp, som kan indikera på spår av naturlig värmebehandling, som i sin tur kan ha orsakats av regional metamorfos eller till och med en strålningskälla. Därutöver studerades sambandet mellan signalstyrkan hos fluoriters band och mineralers kemiska sammansättning. Experimentet visade att blå fluorit fullständigt saknar toppen från T2g, medan de lila och grå fluoriterna hade välutvecklade och lättigenkännliga toppar vid denna position. Således upptäcktes att denna topps närvaro och intensitet är direkt beroende av fluroritens färg, det vill säga av elementen som är inkorporerade i kristallstrukturen, så som metaller, sällsynta jordartsmetaller eller till och med organiska substanser. Därutöver identifierades restdragspänning i den färglösa kvartsen. Spänningen uppskattades ligga i intervallet 0.23 – 1.0 GPa. Ramansystemet användes för att identifiera olika ändelement i granatfamiljen. Ramanspektroskopin hade hög analytisk förmåga och hjälpte till att estimera förhållandet mellan ändelementen i åtta granatprover. I ett fall kunde fluorescens bindas till förekomsten av sällsynta jordartsmetaller i almandinets struktur. Ett kalcitprov visade sig vara felaktigt placerat i samlingen. Detta arbete kommer nu utgöra en god grund för den mineralogiska samlingens handbok.
4

Mutual Favours : the social and scientific practice of eighteenth-century Swedish chemistry /

Fors, Hjalmar, January 2003 (has links)
Diss. Uppsala : Univ., 2003.
5

A Petrological Investigation of the Host Rocks for the Kuj-Kiirunavaara Ore / En Petrologisk Studie av Värdberget för Kuj-Kiirunavaara-Malmen

Sandberg, Holger January 2018 (has links)
The Kiirunavaara mine hosts one of the world’s largest apatite-iron ore mineralisations. This ore body has been subject to large amounts of research as well as extensive mining. The ore body is situated between the syenitic foot wall and the rhyodacitic hanging wall, of which consists of differing mineralogy and characteristics. Both these rock masses contain intrusive porphyry dykes, with distinct characteristics of it own. The aim of this study was to analyse 31 samples, mainly in the form of thin sections, and determine the mineralogy and identify eventual microstructures. This was done through the use of optical mineralogy as well as EDS/WDS analysis at the National Microprobe Lab at Uppsala University. The foot wall consists of syenite-porphyry and is dominated by feldspar in both groundmass as well as phenocrysts. Characteristic for the syenite-porphyry is the rounded nodules containing actinolite, titanite, magnetite and chlorite. The hanging wall is defined as quartz-bearing porphyry. It is a rhyodacitic rock with large amounts of feldspar along with green silicates, quartz, titanite and calcite. The intrusive porphyry dyke-rocks share many similarities with the quartz-bearing porphyry, but contain a finer groundmass with larger amounts of clinopyroxene, as well as lower amounts of quartz, magnetite and titanite. Hydrothermal alteration is prevalent in all the types of rock. Alteration minerals such as actinolite, biotite and chlorite are very common within the Kiirunavaara-rocks. The quartz-bearing porphyry displays the most extensive exposure to hydrothermal fluids. The hydrothermal fluids have penetrated several samples, replacing minerals and leaving very few remnant, older minerals. The quartz-bearing porphyry contains the most prominent deformation structures, of varying extent and magnitude. Magmatic flow structures can be seen in the groundmass, as parallel alignment of feldspar and silicate grains. Evidence of solid-state deformation most commonly occurs as pressure shadows around feldspar phenocrysts. / Kiirunavaara-gruvan är belägen vid en av världens största mineraliseringar av apatit-järnmalm. Denna malmkropp har stått i fokus för både omfattande gruvdrift samt genomgripande forskning. Malmkroppen är belägen mellan den syenitiska liggväggen och den ryodacitiska hängväggen, som består av varierande mineralogi och karaktär. Båda av dessa bergmassor innehåller intrusiv gångporfyr med distinkt karaktär. Målet med denna studie var att analysera 31 prover, främst i form av tunnsliper, och bestämma dess mineralogi samt att identifiera eventuella mikrostrukturer. Detta genomfördes genom användning av optisk mineralogi och EDS/WDS-analys vid det nationella mikrosondslaboratioriet vid Uppsala Universitet. Liggväggen består av syenitporfyr och domineras av fältspat i både mellanmassa och som fenokrister. Karaktäristiskt för syenitporfyren är de rundade nodulerna, innehållandes aktinolit, titanit, magnetit och klorit. Hängväggen definieras som kvartsförande porfyr. Det är en ryodacitisk bergart med stora mängder fältspat, gröna silikater, kvarts, titanit och kalcit. Gångporfyren delar många likheter med den kvartsförande porfyren, men består av en finare mellanmassa med större mängd klinopyroxen, samt innehåller mindre mängder kvarts, magnetit och titanit. Hydrotermal omvandling är allmänt förekommande i alla bergarter i Kiirunavaara. Omvandlingsmineral så som aktinolit, biotit och klorit är väldigt vanliga hos Kiirunavaara-bergarterna. Den kvartsförande porfyren uppvisar den mest omfattande exponeringen av hydrotermala vätskor. De hydrotermala vätskorna har penetrerat ett antal prover och därigenom omvandlat mineral, med liten mängd äldre mineral kvar. Den kvartsförande porfyren innehåller de mest prominenta deformationsstrukturer, av olika omfattning och magnitud. Magmatiska flytstrukturer kan observeras i mellanmassan som parallell orientering av fältspat- och silikatkorn. Tecken av fastfasdeformation förekommer främst i form av tryckskuggor runt fältspatsfenokrister.
6

The Tanzanian Minjingu phosphate rock : possibilities and limitations for direct application /

Szilas, Casper. January 2002 (has links) (PDF)
Ph.d.-afhandling. Den Kongelige Veterinær- og Landbohøjskole, 2002. / Haves også i trykt udg.
7

Samband mellan geologiska och bergmekaniska egenskaper i bergmaterial som bärlager till riksväg 51 : Riksväg 51 sträckan Svennevad - Kvarntorpskorset

Landeman, Philip January 2018 (has links)
This thesis was created to ensure the quality of the rock which would be crushed to base layer construction material, in a road cut at Swedish highway 51, and to find a possible link between the rock's abrasion resistance and its mineralogy. Rock samples were collected, and among other things, several ball mill tests were carried out. The design of the road project was carried out by Loxia Group AB with NCC Group as contractor.A total of 18 rock samples and 2 base layer samples were taken in the area and they were all tested in a ball mill. The results showed that of the 18 rock samples, 2 samples had a ball mill value of less than 16 on the scale, 10 samples had values from 16 to 20, in addition to this, 3 samples had values from 20 to 21 and 3 samples had values in excess of 21 on the Swedish ball mill scale.Of the 3 samples with a ball mill value higher than 21, all contained a larger amount of biotite. Biotite did not appear to the same extent among the samples that ended up further down the ball mill scale. This link was so clear that a conclusion was subsequently drawn from this. The samples taken on the prefabricated base layer both had a ball mill value between 16 and 20. Overall, both the base layer and the rock material passed the Swedish Government’s Transport Administration’s requirements according to "TRVKB 10, Obundna lager". The rock type that was on the south part of the rock cut, adjacent to a deformation zone, had way too poor quality to undergo a ball mill test and therefore there are no values taken from that area.The conclusion of the work is that the rock material overall meets the Swedish Government’s Transport Administration’s requirements for base layer construction materials according to "TRVKB 10 Obundna lager", that a clear link between the proportion of biotite in a rock material and its abrasion resistance exists, and that the broken rock in the south should not be used as construction materials since the rock has insufficient mechanic capacity.

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