Sökning: "Conductivity jump"
Visar resultat 1 - 5 av 7 avhandlingar innehållade orden Conductivity jump.
1. Two Problems in non-linear PDE’s with Phase Transitions
Sammanfattning : This thesis is in the field of non-linear partial differential equations (PDE), focusing on problems which show some type of phase-transition. A single phase Hele-Shaw flow models a Newtoninan fluid which is being injected in the space between two narrowly separated parallel planes. LÄS MER
2. Neutron spectroscopy and computational studies of hydride-ion dynamics in oxide- and nitride-hydride materials
Sammanfattning : This thesis presents studies of the hydride-ion dynamics in the nitride- and oxidehydride materials Ca3CrN3H and BaTiO3-xHx (with x < 0.2). LÄS MER
3. Intermediate Temperature Solid Ionic Conductors and Fuel Cells
Sammanfattning : Novel solid proton conductors based on oxyacid salts and salt-ceramic composites and intermediate temperature fuel cells have been developed in this thesis work. The discovery of proton conduction in these materials introduces a new concept of proton conductors and starts a new research field - Intermediate Temperature Solid Proton Conductors and Fuel Cells. LÄS MER
4. Hydrogen in oxides: a density-functional study of thermodynamic and kinetic aspects
Sammanfattning : Many solid oxides, especially those possessing a perovskite structure, exhibit significant proton conductivity when being acceptor doped and placed in hydrogen-containing atmospheres. Consequently, they have attracted attention foruse as solid membranes in electrochemical devices such as gas sensors, steam electrolyzers and fuel cells. LÄS MER
5. Dynamical properties of metal halide and oxyhydride perovskites
Sammanfattning : This thesis concerns investigations on the dynamical properties of two classes of energy-relevant materials, namely metal halide and oxyhydride perovskites, using neutron scattering techniques. These two classes of materials share the same aspect of a perovskite-type crystal structure but are different in terms of their functional properties and concomitant promise for various technological applications. LÄS MER