Sökning: "hydrogen and oxygen diffusion"
Visar resultat 1 - 5 av 38 avhandlingar innehållade orden hydrogen and oxygen diffusion.
1. Modified oxygen and hydrogen transport in Zr-based oxides
Sammanfattning : Most metals and alloys in the presence of oxygen and moisture will instantaneously react and form a thin (2-5 nm) surface oxide layer. For further reaction to occur, oxygen ions and/or metal cations often diffuse through the already formed oxide layer. LÄS MER
2. Alternative methods for analysing moisture transport in buildings : Utilisation of tracer gas and natural stable isotopes
Sammanfattning : New methods, based on tracer gas measurements and isotopicanalysis can be used to evaluate the moisture properties ofbuilding materials and provide the means for forensic analysisof the origins and history of excessive water in buildings, theimmediate practical consequences of which will be the abilityto improve the moisture performance of constructions. It is shown, in theory and through measurements how thewater vapour permeability of porous building materials can witha good degree of accuracy be estimated with tracer gasmeasurements that provide an efficient alternative to the cupmethod. LÄS MER
3. Nitrogen and Water in High Temperature Corrosion - Insights from First Principle Calculations
Sammanfattning : Service life-time of alloys used in high temperature applications is often limited by corrosion. FeCrAl(Re) alloys are partially designed to form a protective α-alumina oxide scale at elevated temperatures in order to mitigate further oxidation. LÄS MER
4. Escape to space or return to venus : ion flows measured by venus express
Sammanfattning : The present-day Venusian atmosphere is crushingly dense, extremely hot and arid. Yet, in its early history, Venus presumably had a massive amount of water, which, if spread evenly over the surface, provided a water depth of 10s to 100s of meters. Therefore, over the course of the atmospheric evolution, the water must have been removed from Venus. LÄS MER
5. Studies of transport in oxides on Zr-based materials
Sammanfattning : Zr-based materials have found their main application in the nuclear field having high corrosion resistance and low neutron absorption cross-section. The oxide layer that is formed on the surface of these alloys is meant to be the barrier between the metal and the corrosive environment. LÄS MER
