Sökning: "element concentration"

Visar resultat 1 - 5 av 128 uppsatser innehållade orden element concentration.

  1. 1. If Trees Could Talk - Dendrochemistry, a Promising Method for Understanding Pollution History

    Master-uppsats, Göteborgs universitet/Institutionen för geovetenskaper

    Författare :Jonatan Uusitalo; [2023-08-17]
    Nyckelord :;

    Sammanfattning : Heavy metal pollution presents a significant environmental challenge in the Anthropocene era, and understanding pollution history is crucial to address historical pollution and implementing effective mitigation measures. This study stands among a few comprehensive dendrochemical investigations that utilized an extensive dataset and energy dispersive X-ray fluorescence (EDXRF) technique to reconstruct the contamination history of As, Cd, Cu, Ni, Pb, and Zn, with a focus on Cu. LÄS MER

  3. 2. Coupling between iron and humic substances in a land-sea transitional zone in the northern Baltic Sea

    Kandidat-uppsats, Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

    Författare :Anna Osterman; [2023]
    Nyckelord :Iron; Humic substances; Dissolved organic carbon; Baltic Sea; Rivers;

    Sammanfattning : In marine ecosystems around the world, iron (Fe) is a well-studied and important trace element which has been found to stimulate phytoplankton and cyanobacteria growth, as well as limit nitrogen fixation and being essential for Legionella pneumophila which is known as the main cause of Legionnaires’ disease. Fe also contributes to the brownification of freshwater and has recently been documented to increase in concentration in rivers in Sweden. LÄS MER

  4. 3. Validering av FDS för simulering av mindre vätgasläckage inomhus

    Master-uppsats, Lunds universitet/Avdelningen för Brandteknik

    Författare :Emil Hamnes Alavei; Erik Andersson; [2023]
    Nyckelord :Hydrogen; Helium; Ventilation; CFD; FDS; Technology and Engineering;

    Sammanfattning : The prevailing global climate transition is incentivized to occur in a short period of time. Hydrogen is considered a pivotal element towards a renewable energy system. However, the physical and chemical properties of hydrogen give rise to the risk of fire and explosion. LÄS MER

  5. 4. On linear Reaction-Diffusion systems and Network Controllability

    Kandidat-uppsats, KTH/Skolan för teknikvetenskap (SCI)

    Författare :Rebecka Aulin; Felicia Hage; [2023]
    Nyckelord :Turing s model of morphogenesis; FDM; FEM; Controllability; Minimal Control; Least Energy Control;

    Sammanfattning : In 1952 Alan Turing published his paper "The Chemical Basis of Morphogenesis", which described a model for how naturally occurring patterns, such as the stripes of a zebra and the spots of a leopard, can arise from a spatially homogeneous steady state through diffusion. Turing suggested that the concentration of the substances producing the patterns is determined by the reaction kinetics, how the substances interact, and diffusion. LÄS MER

  7. 5. Aluminum levels in the O-horizon of soils near Sundsvall, Sweden : Are levels of Al elevated due to smelter emission?

    Kandidat-uppsats, Umeå universitet/Institutionen för ekologi, miljö och geovetenskap

    Författare :Mattias Sundin; [2023]
    Nyckelord :Aluminium; Smelter emissions; O-horizon; Al concentration; Scots’ pine needles;

    Sammanfattning : Aluminum (Al) is a potentially toxic element for humans, animals, and plants. Al emitted from smelter plants is one source of Al that may be responsible for increased exposure to humans and the environment. LÄS MER