Sökning: "isotope shift"

Visar resultat 1 - 5 av 35 avhandlingar innehållade orden isotope shift.

  1. 1. Atomic Electrons as Sensitive Probes of Nuclear Properties and Astrophysical Plasma Environments : A Computational Approach

    Författare :Asimina Papoulia; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysicumarkivet A:2021:Papoulia; Computational atomic structure; Relativistic atomic theory; Transition probabilities; Abundance analysis; Landé g­-factors; Hyperfine structure; Nuclear quadrupole moments; Isotope shift; Field shift; Nuclear deformation;

    Sammanfattning : This thesis deals with the relativistic modeling of atoms and ions. To interpret the stellar spectra and gain more insight from astrophysical observations, the underlying processes that generate the spectra need to be well understood and described. LÄS MER

  3. 2. Holocene climate and atmospheric circulation changes in northern Fennoscandia : Interpretations from lacustrine oxygen isotope records

    Författare :Christina E. Jonsson; Gunhild Rosqvist; Jan Seibert; Philip Barker; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oxygen isotope; diatom silica; lake sediment; atmospheric circulation; North Atlantic Oscillation; northern Fennoscandia; The Holocene; Little Ice Age; Physical geography; Naturgeografi; Physical Geography; naturgeografi;

    Sammanfattning : This thesis investigates how variations in the oxygen isotopic composition of lake waters in northern Fennoscandia are recorded in lake sediment archives, especially diatoms, and how these variations can be used to infer past changes in climate and atmospheric circulation. Results from analyses of the oxygen isotopic composition of lake water samples (δ18Olakew) collected between 2001 and 2006 show that δ18O of northern Fennoscandian lakes is mainly controlled by the isotopic composition of the precipitation (δ18Op). LÄS MER

  4. 3. Compound-specific stable chlorine isotope analysis : A versatile tool for investigating biochemical and geochemical processes of organochlorine substances

    Författare :Henry Holmstrand; Per Andersson; Örjan Gustafsson; Neil Sturchio; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; compound-specific chlorine isotope analysis; chlorinated organic compounds; Environmental chemistry; Miljökemi;

    Sammanfattning : Chlorinated organic compounds (OCls) from anthropogenic sources are generally considered to be a class of chemicals with high potential for ecotoxicity, including infamous substances such as polychlorinated biphenyls (PCB), dichloro-dibenzo-trichloroethane (DDT) and polychlorinated dibenzo-p-dioxins (PCDD). OCls are also produced naturally, sometimes at the same order of magnitude as anthropogenic compounds. LÄS MER

  5. 4. Laboratory and Stellar Spectra in High Resolution: Studies of Fe, Pt and Tl in Peculiar Stars

    Författare :Gabriele Kalus; Fysiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; high-resolution spectroscopy; hyperfine structure; peculiar stars; iron; platinum; lead; upsilon Sagittarii; HR7775; chi Lupi; isotope shift; Atomic and molecular physics; Atom- och molekylärfysik; Fysicumarkivet A:1997:Kalus;

    Sammanfattning : The near-infrared spectrum of upsilon Sagittarii has been registered using the SOFIN high resolution spectrometer on the Nordic Optic Telescope, La Palma. For the first time 4f-5g transitions of Fe II in any astrophysical spectrum have been identified. LÄS MER

  7. 5. Migration in Prehistory : DNA and stable isotope analyses of Swedish skeletal material

    Författare :Anna Linderholm; Kerstin Lidén; Oliver Craig; Stockholms universitet; []
    Nyckelord :HUMANIORA; HUMANITIES; Migration; ancient DNA; stable isotopes; δ13C; δ15N; δ34S; mtDNA; lactose tolerance; Neolithic; Pitted Ware culture; Funnel Beaker culture; Vikings; Öland; Rössberga; Birka; Björned; Archaeology; Arkeologi; Archaeological Science; laborativ arkeologi;

    Sammanfattning : The main aim of this thesis is to show how scientific methods may be used to look at migration in prehistory on the basis of archaeological material. The individuals examined represent the period 4 000 BC to 1 000 AD and have their geographical origins in various parts of Sweden.Ancient DNA analysis is employed in three cases. LÄS MER