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Visar resultat 1 - 5 av 144 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Thin-film ultraviolet light-emitting diodes realized by electrochemical etching of AlGaN

    Författare :Michael Alexander Bergmann; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; thin-film flip-chip; light-emitting diodes; UVB; AlGaN; thermocompression bonding; substrate removal; ultraviolet light; electrochemical etching; heterogeneous integration; LEDs;

    Sammanfattning : Ultraviolet (UV) light sources have a direct impact on everyone’s life. They are used to sterilize surfaces as well as for water purification. In addition, they are used in green houses to enhance health-promoting substances in plants, for phototherapy to treat skin diseases, for sensing and material curing. LÄS MER

  2. 2. Control of Coherent Extreme Ultraviolet Light and Light Sources

    Författare :Neven Ibrakovic; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ultrafast lasers; XUV optics; high-order harmonic generation; quantum path interference; opto-optical modulation; free electron lasers; nitrogen lasing; Fysicumarkivet A:2019:Ibrakovic;

    Sammanfattning : Coherent extreme ultraviolet (XUV) light sources are necessary for the investigation of physical processes in the natural length and time scales of atoms. These experiments require a high degree of control of the coherent XUV light. LÄS MER

  3. 3. Year-round production of forest seedlings under LED lamps : Biological and energetic implications of indoor cultivation

    Författare :Marco Hernandez Velasco; Uwe Zimmermann; Anders Mattsson; Frank Fiedler; Johanna Riikonen; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Picea abies; Pinus sylvestris; year-round cultivation; forest seedlings; LED lamps; light quality; light quantity; daily light integral; adaptive lighting control; greenhouse integrated photovoltaics; agrivoltaics; seedling growth performance; short-day treatments; cold hardiness; light shock stress; Engineering Science; Teknisk fysik;

    Sammanfattning : Year-round cultivation of forest seedlings under light emitting diodes (LED) is a technology receiving increased attention from nurseries in the boreal forest regions. In these areas, the climate is characterized by strong seasonal fluctuations, resulting in short vegetation periods with narrow time windows for seedling transplanting and outdoor growth. LÄS MER

  4. 4. Ultraviolet radiation cataract

    Författare :Konstantin Galichanin; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :lens;

    Sammanfattning : Cataract is the leading cause of blindness in the world. Epidemiological and experimental evidence supports a link between mid-range ultraviolet radiation (UVR-B) exposure and the development of cataract. LÄS MER

  5. 5. Towards Novel AlGaN-Based Light Emitters

    Författare :Martin Stattin; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; AlGaN; light emitting diode; deep ultraviolet; III-Nitrides; near infrared; quantum cascade laser;

    Sammanfattning : The unique properties of the AlGaN semiconductors make them a suitable choice for optoelectronic devices at both short and long wavelengths, based on interband and intersubband transitions, respectively. What sets AlGaN apart from other wide-bandgap semiconductors is the possibility to obtain both p- and n-type conductivity as well as the direct bandgap. LÄS MER