Sökning: "Temperature effect"

Visar resultat 21 - 25 av 2118 avhandlingar innehållade orden Temperature effect.

1. 21. Temperature effects on UV-B induced DNA damage and repair in plants and a lichen

   Författare :Markus Paulsson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Tobacco Nicotiana tabacum ; Temperature; Subarctic; Plants; Photoreactivation; Photolyase; Lichen; DNA damage; Cyclobutane pyrimidine dimers CPD ; 6-4 Photoproducts; Cladonia arbuscula ssp. mitis; Ultraviolet radiation; UV-B; Vaccinium vitis-idaea; Plant genetics; Växtgenetik;

   Sammanfattning : All living organisms have DNA and since DNA is essential to life it must be repaired when damaged. UV radiation is one of the major DNA damaging agents, which photosynthetic organisms cannot avoid. LÄS MER

3. 22. High-Temperature Corrosion-Fatigue of Cast Alloys for Exhaust Manifolds

   Författare :Shengmei Xiang; Joakim Odqvist; Baohua Zhu; Johan Ahlström; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High temperature; corrosion fatigue; low-cycle fatigue; cast alloys; high-temperature oxidation; intermetallic phase; Teknisk materialvetenskap; Materials Science and Engineering;

   Sammanfattning : The introduction of gas-driven Otto engine and the corresponding usage of bio-fuels in heavy-duty engines will render the exhaust atmosphere more corrosive and bring a higher working temperature to exhaust manifolds. The current service material, a ferritic ductile cast iron called SiMo51, will soon meet its upper temperature limit set by the ferrite-austenite transformation at 860ºC. LÄS MER

4. 23. Hydronic Heating Systems The Effect of Design on System Sensitivity

   Författare :Anders Trüschel; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; shunt group; controllability; district heating; room temperature; air heater; heating coil; thermal power output; deviations; water return temperature; valve group; hydronic heating; radiator system; P-band;

   Sammanfattning : This thesis starts from the recognition that a hydronic heating system can be optimised, but can never be totally perfect. Sooner or later, in practice, deviations - caused by one or more components having slightly different characteristics or settings than they are assumed or supposed to have - arise. LÄS MER

5. 24. Modelling and experimental testing of truck tyre rolling resistance

   Författare :Jukka Hyttinen; Lars Drugge; Jenny Jerrelind; James Busfield; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Truck tyre; PRF; filler-reinforced rubber; ambient temperature; rubber testing; constitutive modelling; parametrisation; rolling resistance; load cell; Fletcher-Gent effect; Payne effect; Lastbilsdäck; PRF; förstärkande fyllmedel; gummi; omgivningstemperatur; gummiprovning; konstitutiv modellering; parametrisering; rullmotstånd; lastcell; Fletcher-Gent effekt; Payne effekt; Teknisk mekanik; Engineering Mechanics;

   Sammanfattning : Truck transport offers a versatile way to ship goods in regional, long haulage and urban applications. However, the heavy truck sector accounts for 6 % of total greenhouse gas emissions in the European Union. Therefore, there is a need for a substantial reduction of these emissions to secure the sustainability of Earth for future generations. LÄS MER

7. 25. Low Temperature Waste Heat Recovery in Internal Combustion Engines

   Författare :Vikram Singh; Förbränningsmotorer; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Low Temperature Waste Heat Recovery; Rankine cycle; Coolant Temperature; Working Fluids;

   Sammanfattning : Over the past few decades, the automotive industry has increasingly looked towards increasing the efficiency of the internal combustion engine to meet more stringent emission norms and as a measure to meet demands for improved air quality in cities. One method to improve the internal combustion engine efficiency is to recover some of the energy lost to the coolant and the exhaust using a secondary thermodynamic cycle such as an Organic Rankine Cycle. LÄS MER