Sökning: "elevated temperature"

Visar resultat 11 - 15 av 414 avhandlingar innehållade orden elevated temperature.

1. 11. High Temperature Wear Processes

   Författare :Sinuhe Hernandez; Bojan Podgornik; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinelement; Machine Elements;

   Sammanfattning : Moving machine assemblies are increasingly exposed to extreme operating conditions involving high temperatures owing to demands on higher power densities, high performance/efficiency and extreme environments. The changes in surface and near surface properties of contacting surfaces caused by exposure to high temperature and deformation govern the occurrence of friction, wear and material transfer of the tribological system. LÄS MER

3. 12. Tribology of polymer composites for elevated temperature applications

   Författare :Jonna Lind; Åsa Kassman Rudolphi; Stefan Silverbåge; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; tribology; polymer composite; friction; wear; Teknisk fysik med inriktning mot tribomaterial; Engineering Science with specialization in Tribo Materials;

   Sammanfattning : Polymers as construction material are common in the industry. Although more recently the use of polymer composites in more demanding applications has increased, requiring more of them mechanically, tribologically and thermally. To enhance the properties various fillers are used, from common glass fibers to more advanced nanoparticles. LÄS MER

4. 13. Environment Related Surface Phenomena and their Influence on Properties of Ti-6Al-4V and Ti-6Al-2Sn-4Zr-2Mo : Oxidation at Elevated Temperature and Corrosion During Chemical Treatment

   Författare :Birhan Sefer; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materialteknik; Engineering Materials;

   Sammanfattning : This doctoral thesis covers investigation of the surface phenomena of Ti-6Al-4V and Ti-6Al-2Sn-4Zr-2Mo alloys related with oxidation at elevated temperature and corrosion duringchemical treatment in hydrofluoric-nitric acid (HF/HNO3) solutions. The explored phenomenaare related to manufacturing and service conditions of aero-engine components. LÄS MER

5. 14. Lineshape in Quantum Cascade Lasers - Temperature, Screening and Broadening

   Författare :Rikard Nelander; Matematisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum Cascade Lasers; quantum wells; spectral lineshape; Non-Equilibrium Green s Functions; screening; temperature dependence;

   Sammanfattning : This dissertation deals with the optical properties of Quantum Cascade Lasers (QCLs). Studies are performed using transport calculations employing the theory of Non-Equilibrium Green's Functions, and screening is studied within the Random Phase Approximation. Focus is put on the temperature dependent effects in THz QCLs. LÄS MER

7. 15. Insights into Marine Fish Physiology in a Changing World

   Författare :Karine Bresolin de Souza; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ocean acidification; carbon dioxide; temperature; global warming; Hippoglossus hippoglossus; Gasterosteus aculeatus; immune system; energy metabolism enzymes; oxidative stress; proteomics; behaviour;

   Sammanfattning : Ocean acidification and global warming are largely caused by increased levels of atmospheric CO2, and marine fish are exposed to both these stressors simultaneously. Although the effects of temperature on fish have been investigated over the last century, the effects of moderate CO2 exposure and the combination of both stressors are not well-understood, especially long-term effects. LÄS MER