Sökning: "light"

Visar resultat 16 - 20 av 5652 avhandlingar innehållade ordet light.

1. 16. Single-cycle undulator light

   Författare :Georgii Shamuilov; Vitaliy Goryashko; Gianluca Geloni; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; terahertz technology; light sources; electron beams; space charge; waveform control; optical magnetic lens; Fysik; Physics;

   Sammanfattning : The past decade has witnessed a sharp rise of interest in coherent terahertz (THz) light sources for applications in condensed-matter physics. These sources are a powerful tool for studying collective excitations in solid-state systems: THz light can directly couple to low-energy excitations on the meV-scale such as the collective excitations of spins and phonons. LÄS MER

3. 17. Light, stress and herbivory : from photoprotection to trophic interactions using Arabidopsis thaliana as a model organism

   Författare :Martin Frenkel; Jon Moen; Stefan Jansson; Don Cipollini; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arabidopsis thaliana; photoprotection; herbivory; light-stress; jasmonate; fitness; FDE; dual-choice; Biology; Biologi;

   Sammanfattning : Photosynthesis is the most important process for nearly all life on earth. Photosynthetic organisms capture and transfer light energy from the sun into chemical energy which in turn provides a resource base for heterotrophic organisms. Natural light regimes are irregular and vary over magnitudes. LÄS MER

4. 18. 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

5. 19. Form, rörelse, ljus : en studie över Johannes Olivegrens kyrkoarkitektur

   Författare :Anders Björkman; Umeå universitet; []
   Nyckelord :HUMANIORA; HUMANITIES; Johannes Olivegren; post-war church architecture; Neo-Expressionism; Olivegren; Johannes; 1926-1989; Kyrkor-- Arkitektur -- Sverige -- 1900-talet;

   Sammanfattning : The present study examines the church architecture of Johannes Olivegren (1926-89). Winning a contest on small-church design in 1953 proved to be the prelude to a career in architecture which by 1975 had resulted in the raising of a total of eighteen churches. LÄS MER

7. 20. Molecules and Light : A Journey into the World of Theoretical Spectroscopy

   Författare :Iulia Emilia Brumboiu; Barbara Brena; Heather Kulik; Uppsala universitet; []
   Nyckelord :Theoretical spectroscopy; XPS; NEXAFS; PCBM; Metal phthalocyanine; Organic solar cells; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik; Physics with spec. in Atomic; Molecular and Condensed Matter Physics;

   Sammanfattning : Two of the main technological challenges of the century are the production of clean energy, on the one hand, and the development of new materials for electronic and spintronic applications that could increase the speed and the storage capacity of regular electronic devices, on the other hand. Organic materials, including fullerenes, organic polymers and organic molecules with metal centres are promising candidates for low-cost, flexible and clean technologies that can address these challenges. LÄS MER