Search for dissertations about: "isotopes"

Showing result 1 - 5 of 298 swedish dissertations containing the word isotopes.

  1. 1. Crustal evolution of the Arabian–Nubian Shield : Insights from zircon geochronology and Nd–Hf–O isotopes

    Author : Fitsum Girum Yeshanew; Victoria Pease; Martin J. Whitehouse; Robert J. Stern; Stockholms universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; Gondwana; Arabian–Nubian Shield; Azania; zircon U–Pb–O–Hf isotopes; Nd isotopes; Cambrian Sandstones; juvenile; pre–Neoproterozoic; reworking; Geology; geologi;

    Abstract : The Arabian–Nubian Shield (ANS) represents a major site of juvenile Neoproterozoic crustal addition on Earth and documents Neoproterozoic tectonics bracketed by two supercontinent cycles, namely the fragmentation of Rodinia and the amalgamation of Gondwana. There is general consensus that the ANS formed by juvenile magmatic arc accretion and subsequent shield–wide post–tectonic magmatism. READ MORE

  2. 2. Isotopes as Mechanism Spies : Nucleophilic Bimolecular Substitution and Monoamine Oxidase B Catalysed Amine Oxidation Probed with Heavy Atom Kinetic Isotope Effects

    Author : Susanna MacMillar; Olle Matsson; Anita Hussénius; Daniel M. Quinn; Uppsala universitet; []
    Keywords : Organic chemistry; nucleophilic bimolecular substitution SN2; kinetic isotope effects; precision conductometry; monoamine oxidase B MAO B; reaction mechanism; carbon 11C 14C kinetic isotope effect; ion pairing triple-ion formation; para-substituted benzyl chlorides; tetrabytylammonium cyanide; Organisk kemi;

    Abstract : This thesis concerns the study of reaction mechanisms by means of kinetic isotope effects (KIEs). Studies of the nucleophilic bimolecular substitution (SN2) reaction had the dual purpose of improving our fundamental understanding of molecular reactivity and assessing the ability of kinetic isotope effects to serve as mechanistic tools. READ MORE

  3. 3. Our Bones, who art contaminated : Glues, strontium isotopes, and mobility in early Swedish Christians

    Author : Crista Adelle Wathen; Kerstin Lidén; Sven Isaksson; Christophe Snoeck; Stockholms universitet; []
    Keywords : HUMANITIES; HUMANIORA; HUMANIORA; HUMANITIES; Strontium isotopes; contamination; conservation; glues; Christianity; mobility; early Christians; Sweden; Varnhem; Västerhus; bones; teeth; Scientific Archaeology; arkeologi med inriktning mot laborativ arkeologi;

    Abstract : This thesis aims to build upon previous research into contamination and its effects on isotopes by focusing on the strontium isotopic ratio (87Sr/86Sr), which is used in mobility studies to study the movements of past humans and animals and to build past economic trading networks. Contamination is a broad topic, and in the scope of this thesis, it concerns the introduction of contaminants from the soil after interment and the post-excavation preservation efforts. READ MORE

  4. 4. Iron isotopes in aquatic systems

    Author : Sarah Conrad; Johan Ingri; Michael Bau; Luleå tekniska universitet; []

    Abstract : The cycling of iron (Fe) is a key component for understanding water quality and biogeochemical processes. It serves as mediator during biotic and abiotic processes, as electron acceptor during the degradation of organic matter, as surface for trace element and organic matter adsorption, and is necessary for primary production processes. READ MORE

  5. 5. Perspectives from a human-centred archaeology : Iron Age people and society on Öland

    Author : Helene Wilhelmson; begravning och social identitet Gravarkeologiska forskargruppen – Död; []
    Keywords : HUMANIORA; HUMANITIES; HUMANIORA; HUMANITIES; Osteology; bioarchaeology; Iron Age; Scandinavia; 3D; digital; Image Based Modeling; GIS; isotopes; Oxygen; Strontium; Carbon; Nitrogen; trophic level effect; fractionation; chronology; network; Virtual Taphonomy; human-centred archaeology; mortographies; dietary shift; integration; immigration; diet; migration; violence; burial; Viking Age; Öland; island;

    Abstract : The objective of this study was to develop, test and evaluate a specifically defined interdisciplinary approach—the human-centred approach—as applied to a case study, Iron Age Öland. Four themes were selected to highlight different aspects of particular interest in Öland: taphonomy, diet, migration, and social organization. READ MORE