Sökning: "ppm"

Visar resultat 36 - 40 av 210 uppsatser innehållade ordet ppm.

  1. 36. Detection of nitrous oxide through IR-DFWM in gas flows with future application in ammonia flames

    Master-uppsats, Lunds universitet/Förbränningsfysik; Lunds universitet/Fysiska institutionen

    Författare :Martin Passad; [2021]
    Nyckelord :Physics; Optics; Lasers; Environment; Hydrogen; Hydrogen Energy; Ammonia Energy; DFWM; Ammonia; Nitrous Oxide; Ammonia Flame; Ammonia Combustion; Physics and Astronomy;

    Sammanfattning : This thesis report on an investigation into the applicability of mid-infrared degenerate four-wave mixing (IR-DWFM) as a method to detect N\(_2\)O in ammonia flames. DFWM has previously been used for concentration measurements on other molecules, but has never, to the author's knowledge, been applied to measure N\(_2\)O in ammonia flames before. LÄS MER

  3. 37. Statliga eller Privata PPM-fonder? En komparativ studie om att aktivt välja fonder eller passivt vara kvar i statens förvalsalternativ.

    Kandidat-uppsats, Göteborgs universitet/Institutionen för nationalekonomi med statistik

    Författare :Gustav Johannesson; Karl Nordenlöw; [2020-06-30]
    Nyckelord :;

    Sammanfattning : This paper examines the two investment strategies available within the Swedish Premium Pension System with the aim of illuminating whether it is more beneficial to actively select funds or to remain with the default portfolio option (AP7 Såfa). In order to answer this question, this paper splits the portfolio AP7 Såfa into its two component government funds, AP7 Aktiefond and AP7 Räntefond. LÄS MER

  4. 38. Resolving temporal links between the Högberget granite and the Wigström tungsten skarn deposit in Bergslagen (Sweden) using trace elements and U-Pb LA-ICPMS on complex zircons

    Master-uppsats, Lunds universitet/Geologiska institutionen

    Författare :Anders Plan; [2020]
    Nyckelord :Bergslagen; Wigström; Högberget; geochronology; geochemistry; U-Pb; REE; trace element; zircon; hydrothermal zircon; LA-ICPMS; SEM; skarn; tungsten; wolfram; scheelite; deposit; ore; critical raw material; Earth and Environmental Sciences;

    Sammanfattning : Combined U-Pb and REE trace element LA-ICPMS analyses were performed on zircons, from the scheelite-bearing Wigström skarn, associated micro-granitic dykes and the highly evolved parental Högberget (sensu stricto) granite. Combined systematic of zircon typology and microtextures, trace elements and isotopic chemistry suggest the presence of several diverse zircon types, spanning from early- to late- magmatic stage into a hydrothermal stage. LÄS MER

  5. 39. A model for heterogenic catalytic conversion of carbon dioxide to methanol

    Kandidat-uppsats, Linköpings universitet/Institutionen för fysik, kemi och biologi

    Författare :Elin Johannesson; [2020]
    Nyckelord :Carbon dioxide; methanol; heterogeneous catalysis; zinc oxide; computational chemistry; density functional theory;

    Sammanfattning : Since our society became industrialised, the levels of carbon dioxide in our atmosphere have been steadily rising, to the point where it in early 2020 at is 413 ppm. The high concentration is causing several troubling effects worldwide because of the increase in mean temperature that it creates, which causes longer draughts, more severe floods, and rising seawater levels to name a few. LÄS MER

  7. 40. CO2-emissions from rivers and streams : Seasonal variation of pCO2-levels and CO2-fluxes

    Master-uppsats, Mittuniversitetet/Institutionen för ekoteknik- och hållbart byggande

    Författare :Emile Vandeburie; [2020]
    Nyckelord :Eddy Covariance; CO2-flux; air-water gas exchange;

    Sammanfattning : Since the industrial evolution, the CO2-levels have been increasing in a way that’s never seen in the history of the earth. To mitigate and adapt to the happening climate change it is really important to understand the global carbon cycle and each component that plays a role in it. LÄS MER