Sökning: "thermal ageing"

Visar resultat 6 - 10 av 62 avhandlingar innehållade orden thermal ageing.

1. 6. Thermal Isomerization of Azobenzene Side Chain Copolymers

   Författare :Viktoria Skeppstedt; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; free volume; thermal isomerization; positron annihilation lifetime spectroscopy; physical ageing; phthalate; methyl methacrylate polymer; azo polymers; plasticization;

   Sammanfattning : Irradiation of azobenzene induces isomerization between its trans- and cis forms. By introduction of azobenzene chromophores in polymers, it is possible to optically control a variety of polymer properties. The isomerization of azobenzene can be used to influence conformational, optical or surface properties of the poly mer material. LÄS MER

3. 7. Modeling framework for ageing of low alloy steel

   Författare :Magnus Boåsen; Pål Efsing; Jonas Faleskog; Carl F. O. Dahlberg; Christian Niordson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Low alloy steel; length scale effects; size effects; plasticity; cleavage fracture; brittle fracture; weakest link; ageing; weld metal; Hållfasthetslära; Solid Mechanics;

   Sammanfattning : Ageing of low alloy steel in nuclear applications commonly takes the form as a hardening and an embrittlement of the material. This is due to the evolution of the microstructure during irradiation and at purely thermal conditions, as a combination or separate. LÄS MER

4. 8. Long-term performance of polymeric materials in nuclear power plants

   Författare :Payam Pourmand; Ulf W. Gedde; Sue Burnay; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; EPDM; thermal ageing; radiation ageing; portable NMR spectroscopy; modulus profiling; condition monitoring; plasticizer migration; Kemi; Chemistry;

   Sammanfattning : Access to energy is crucial for modern societies to function sustainably. In addition, nuclear power has for a long time been considered a reliable source of energy. However, the majority of nuclear power plants are reaching the end of their service lifetimes, and it is crucial to verify that every component can withstand the added service time. LÄS MER

5. 9. Flow-induced Surface Defects and Ageing Behaviour of Injection-moulded Polymers

   Författare :Giovanna Iannuzzi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; PP; surface defects; flow marks tiger stripes ; ageing; Injection moulding; ABS; rheological properties; degradation; surface topography; discolouration;

   Sammanfattning : Injection moulding is one of the most commonly used manufacturing methods for the production of polymer-based components such as car bumpers and other automotive details. The surface appearance of these products is of great importance since it is directly connected to the perceived quality. LÄS MER

7. 10. Optical Efficiency of Low-Concentrating Solar Energy Systems with Parabolic Reflectors

   Författare :Maria Brogren; Arne Roos; Björn Karlsson; Andreas Häberle; Uppsala universitet; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER