Sökning: "electric conductivity"

Visar resultat 6 - 10 av 57 uppsatser innehållade orden electric conductivity.

  1. 6. Investigating surface spring snow : Changes in the isotopic composition and conductivity along an orographic precipitation gradient in northern Fennoscandia

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

    Författare :Sara Andersson; [2023]
    Nyckelord :stable isotopes; snow; precipitation; hydrology; orography; earth science;

    Sammanfattning : Stable isotopes of oxygen (O18) and hydrogen (H2) are used as proxies of past climates when ice preserved in the polar icecaps. The main assumption when doing paleoclimatic reconstructions using these isotopes is that the isotopic composition of the snow that turned into ice reflect the present temperature of the planet during deposition. LÄS MER

  2. 7. Review and Design of DC Electrical Field Measurement Systems and Related Developments : For Measurements Around HVDC Cable Terminations

    Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Emil Bergvall; [2023]
    Nyckelord :DC Field Probe; Measurement Systems; Electric Fields; Cable Termination; Ion Drift; Conductivity; HVDC; Field Mill; Field Simulations; Positioning System; MEMS; Electro-Optics; DC Fält Prob; Mätsystem; Elektriska Fält; Kabelavslut; Jondrift; Ledningsförmåga; HVDC; Fältkvarn; Fält Simulationer; Positioneringsystem; MEMS; Elektro-Optik;

    Sammanfattning : With power generation and consumption placed further away from each other, with for example increased offshore power production, the need for HVDC transmission systems increases. As voltage levels in the HVDC transmission system are raised, the losses can be decreased, enabling efficient power transfer over longer distances. LÄS MER

  3. 8. Characterisation of Ionic Liquid doped Polybenzimidazole Membranes for Application in High-Temperature Proton Exchange Membrane Fuel Cells

    Master-uppsats, Lunds universitet/Kemiteknik (CI)

    Författare :Adam Jacobsson Trönndal; [2023]
    Nyckelord :Fuel cells; Phosphoric acid; Polybenzimidazole; PA-PBI; Ionic liquid; IL; High temperature proton exchange membrane fuel cell; HT-PEMFC; Electrochemical impedance spectroscopy; EIS; IL-PBI; Chemical engineering; Technology and Engineering;

    Sammanfattning : In this study four membranes were tested and evaluated against each other for use in high-temperature proton exchange membrane fuel cell (HT-PEMFC) applications. A phosphoric acid (PA) doped polybenzimidazole (PBI) membrane, was used as a reference as the current state-of-the-art. LÄS MER

  4. 9. Active dielectrophoretic trapping for deterministic single-cell encapsulation in droplet microfluidics

    Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Prasanna Surana; [2023]
    Nyckelord :negative dielectrophoresis; droplet microfluidics; low conductivity medium; cell viability; COMSOL electric field simulation; joule heating; Rhodamine B temperature measurement; microfluidic chip cleaning; negativ dielektrofores; droppmikrofluidik; medium med låg konduktivitet; cellviabilitet; COMSOL elektrisk fältsimulering; jouleuppvärmning; Rhodamine B temperaturmätning; mikrofluidisk chiprengöring;

    Sammanfattning : The research work focuses on optimizing various parameters for controlling cells using negative dielectrophoresis and entrapping them in droplet microfluidics. This is achieved by developing a conductivity medium, combining CytoRecovery, BSA, and EDTA, to maintain a steady count of single cells with good viability over an extended period. LÄS MER

  5. 10. Investigation of sub-surface ocean induction on Jupiter's icy moon Europa

    Kandidat-uppsats, Uppsala universitet/Institutet för rymdfysik, Uppsalaavdelningen; Uppsala universitet/Rymd- och plasmafysik

    Författare :Cornelia Ekvall; [2022]
    Nyckelord :rymdfysik; Jupiter; Europa; magnetiskdipol; JUICE;

    Sammanfattning : Following previous studies, a theoretical model for the induced magnetic field by Europa, one of Jupiter's icy moons, is presented. The aim of the model is to find evidence for the existence of a sub-surface ocean on the moon. LÄS MER