Search for dissertations about: "arne roos"

Showing result 1 - 5 of 12 swedish dissertations containing the words arne roos.

2. 1. Optical selectivity of some metal oxides for solar energy applications

   Author : Arne Roos; Uppsala universitet; []
   Keywords : NATURAL SCIENCES; NATURVETENSKAP;

   Abstract : .... READ MORE

4. 2. Alternative Stable States in Size-Structured Communities : Patterns, Processes, and Mechanisms

   Author : Arne Schröder; Lennart Persson; André M. de Roos; Tim Benton; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; biomass overcompensation; Chaoborus; emergent Allee effect; Heterandria formosa; juvenile recruitment bottlenecks; ontogenetic niche shifts; Poecilia reticulata; Biology; Biologi;

   Abstract : Alternative stable states have been, based on theoretical findings, predicted to be common in ecological systems. Empirical data from a number of laboratory and natural studies strongly suggest that alternative stable states also occur in real populations, communities and ecosystems. READ MORE

5. 3. Preparation and Characterisation of Sputtered Titanium- and Zirconium Nitride Optical Films

   Author : Kent Andersson; Arne Roos; M. Georgson; Uppsala University Department of Technology Solid State Physics Group; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : Multilayered interference coatings based on titanium- and zirconium nitride and designed for solar control have been prepared using reactive d c magnetron sputtering. Preparation effects and degradation mechanisms were investigated. It was shown that the quality of the nitride strongly depends on the degree of crystallinity in the underlying oxide. READ MORE

6. 4. Optical Efficiency of Low-Concentrating Solar Energy Systems with Parabolic Reflectors

   Author : Maria Brogren; Arne Roos; Björn Karlsson; Andreas Häberle; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering physics; Photovoltaic cells; Photovoltaic-thermal systems; Parabolic reflectors; Optical properties; Reflector materials; Optical efficiency; Accelerated ageing; Outdoor ageing; Building-integrated photovoltaics; Teknisk fysik; Engineering physics; Teknisk fysik;

   Abstract : Solar electricity is a promising energy technology for the future, and by using reflectors for concentrating solar radiation onto photovoltaic cells, the cost per produced kWh can be significantly reduced. The optical efficiency of a concentrating system determines the fraction of the incident energy that is transferred to the cells and depends on the optical properties of the system components. READ MORE

7. 5. Preparation and Characterization of Sputter Deposited Spectrally Selective Solar Absorbers

   Author : Kristina Gelin; Ewa Wäckelgård; Arne Roos; Björn Karlsson; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering physics; spectrally selective solar absorber; thermal emittance; solar absorptance; sputter deposition; infrared reflectance; Teknisk fysik; Engineering physics; Teknisk fysik;

   Abstract : The optical efficiency of a commercially available sputter deposited spectrally selective solar absorber was improved. The main purposes were to decrease the thermal emittance, increase the solar absorbtance of the absorber and to protect the substrate from degradation due to environmental influence. READ MORE