Sökning: "Hydrogen effect"

Visar resultat 11 - 15 av 439 avhandlingar innehållade orden Hydrogen effect.

1. 11. Hydrogen, an Energy Carrier of the Future

   Författare :Christian Hulteberg; Avdelningen för kemiteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical technology and engineering; Catalysts; Aerosols; Gasification; Hydrogen; Systems; Kemiteknik och kemisk teknologi;

   Sammanfattning : The climate is changing, something that many scientists correlate to increased emissions of greenhouse gases. The effluent that is considered to have the highest impact on global warming is carbon dioxide, when effect and quantity are taken into account. LÄS MER

3. 12. Small-Scale Production of Fuel-Cell Hydrogen

   Författare :Christian Hulteberg; Avdelningen för kemiteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hydrogen; Chemical Engineering; Catalysis; Small-Scale;

   Sammanfattning : The work presented here aims at producing hydrogen for proton-exchange fuel-cell applications from hydrocarbons. This thesis describes an integrated catalytic converter comprising a steam-reforming reactor (heat of reaction supplied by catalytic combustion), a water-gas shift reactor and a preferential oxidation of carbon monoxide reactor, and the work performed on the fuel processing catalysts therein. LÄS MER

4. 13. The rule of hydrogen and rare earth metals in the formation of protective metal-oxides

   Författare :Bent N. Tveten; KTH; []
   Nyckelord :chromium; high-temperature corrosion; oxide growth; scale adherence; hydrogen; yttria; REM; reactive element effect; gas phase analysis;

   Sammanfattning : The effects of hydrogen and rare earth metal (REM) additionson the oxidation behavior of metals and alloys that formchromia, alumina and zirconia in 20 mbar O2and/or H2O have been investigated at elevated temperatures.The metal-gas reactions were studied by the use of isotopicallylabeled gas in combination with mass spectrometry and bymeasuring changes in the total pressure in a closed reactionchamber. LÄS MER

5. 14. Effect of water contamination on the diffused content of hydrogen under stress in AISI-52100 bearing steel

   Författare :Tajammal Imran; Maskinelement; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vacuum technology; hydraulics; Mechanical engineering; materialteknik; Materiallära; Material technology; Hydrogen Diffusion; Rolling Element; Machine Elements; Tribology; Hydrogen Embrittlement; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

   Sammanfattning : Abstract Hydrogen embrittlement is a degradation process of mechanical/tribological properties (toughness, wear etc.) of mating steel surfaces. This is caused by the presence and interaction of hydrogen with applied stresses. Therefore, it is important to quantify the hydrogen content which could be dissolved under applied stresses in steel. LÄS MER

7. 15. Effect of boron and hydrogen on microstructure and mechanical properties of cast Ti-6Al-4V

   Författare :Raghuveer Gaddam; Magnus Hörnqvist; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Titanium alloy; Metallography; Fractography; Castings; Low cycle fatigue; Hydrogen; Boron; Materialteknik; Engineering Materials;

   Sammanfattning : Titanium and its alloys are widely used in applications ranging from aeroengines and offshore equipment to biomedical implants and sporting goods, owing to their high ratio of strength to density, excellent corrosion resistance, and biomedical compatibility. Among the titanium alloys used in aerospace, Ti-6Al-4V (an α+β alloy) is the most widely used, in applications in which the temperature may reach 350°C, at which point it retains good fatigue and fracture properties as well as moderate tensile strength and ductility. LÄS MER