Sökning: "light limitation"

Visar resultat 1 - 5 av 80 avhandlingar innehållade orden light limitation.

  1. 1. Slow and stopped light by light-matter coherence control

    Författare :Jonas Tidström; Lars Thylén; Mauritz Andersson; Jesper Mørk; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; slow light; stored light; stopped light; light-matter coherence; electromagnetically induced transparency; rubidium atoms; Physics; Fysik; Photonics; Fotonik;

    Sammanfattning : In this thesis we study light-matter coherence phenomena related to the interaction of a coherent laser field and the so-called Λ-system, a three-level quantum system (e.g., an atom). We observe electromagnetically induced transparency (EIT), slow and stored light in hot rubidium vapor. LÄS MER

  2. 2. Beyond carbon-limitation : A re-evaluation of the ecological role of photorespiration and direct oxygen photoreduction in seagrasses

    Författare :Pimchanok Buapet; Mats Björk; Ilana Berman-Frank; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Carbon limitation; Chlorophyll fluorescence; Electron transport rate; Irradiance; Mehler reaction; Non-photochemical quenching; Photorespiration; Photosynthetic activity; Plant Physiology; växtfysiologi;

    Sammanfattning : Seagrasses living in shallow coastal waters are regularly subjected to changes in environmental conditions including the two essential factors for photosynthesis: dissolved inorganic carbon (DIC) and irradiance. This thesis focuses on the photosynthetic responses of seagrasses to carbon limitation induced by community metabolism and/or high light intensities. LÄS MER

  3. 3. Effects of temperature and terrestrial carbon on primary production in lake ecosystems

    Författare :Mohammed Hamdan; Jan Karlsson; Pär Byström; Erin R. Hotchkiss; Lars-Anders Hansson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lakes; primary production; benthic; pelagic; carbon dioxide limitation; light limitation; nutrient limitation; browning; warming; allochthonous carbon; grazing; trophic cascades;

    Sammanfattning : Climate warming is predicted to affect northern lake food webs in two ways: (1)directly via changes in water temperature and ice conditions, and (2) indirectlyvia changes in catchment characteristics and processes that influence input ofallochthonous coloured dissolved organic matter (cDOM) and nutrients. Input ofcDOM increases carbon dioxide (CO2) availability, causes brownification andreduced light conditions, and may increase nutrient availability especially forpelagic primary producers. LÄS MER

  4. 4. Angle dependent light scattering of functional nanoparticle composites

    Författare :JunXin Wang; Gunnar Niklasson; Anand Srinivason; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; light scattering; nano particle; absorption; radiative transfer; Solid State Physics; Fasta tillståndets fysik;

    Sammanfattning : Varies functional nanoparticles play crucial roles in energy- and optical- related applications. The incorporation of functional nanoparticles into non-absorbing polymers to form optical absorption and scattering thin films have attracted considerable interest due to a successful selection of particles and matrices, synergistic effects of separation and fixation of particles, and controllable layer thicknesses and structures. LÄS MER

  5. 5. Light Trapping and Alternative Electrodes for Organic Photovoltaic Devices

    Författare :Kristofer Tvingstedt; Olle Inganäs; Peter Peumans; Linköpings universitet; []
    Nyckelord :Light trapping; Organic solar cells; Tandem cells; Polymer solar cells; Plastsolceller; NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : Organic materials, such as conjugated polymers, have emerged as a promising alternative for the production of inexpensive and flexible photovoltaic cells. As conjugated polymers are soluble, liquid based printing techniques enable production on large scale to a price much lower than that for inorganic based solar cells. LÄS MER