Sökning: "Conductivity"
Visar resultat 6 - 10 av 893 avhandlingar innehållade ordet Conductivity.
6. On Thermal Conductivity and Strength in Compacted Graphite Irons : Influence of Temperature and Microstructure
Sammanfattning : Thermal conductivity, hardness and strength are all highly important material properties, affecting the performance and life expectancy of components operating at elevated temperatures. The main purpose of this work has been to increase the knowledge and understanding concerning how mechanical and physical properties are affected by temperature and microstructure in compacted graphite irons. LÄS MER
7. Thermal conductivity of wide and ultra-wide bandgap semiconductors
Sammanfattning : This PhD thesis presents experimental and theoretical studies of the thermal conductivity of wide and ultra-wide bandgap semiconductors including GaN, AlN, β-Ga2O3 binary compounds, and AlxGa1−xN, ScxAl1−xN, YxAl1−xN ternary alloys. Thermal conductivity measurements are conducted using the transient thermoreflectance (TTR) technique and the results are interpreted using analytical models based on the solution of the Boltzmann transport equation (BTE) within the relaxation time approximation (RTA). LÄS MER
8. Thermal Conductivity of Materials under Conditions of Planetary Interiors
Sammanfattning : The presented thesis focuses on study of transport and thermoelastic properties of materials under conditions of planetary interiors by means of high-pressure experimental tools and finite element modeling, and their role in the dynamics and states of cores of terrestrial planets. Experiments in laser-heated diamond anvil cell (LHDAC) in combination with numerical simulations of heat transfer in DAC are shown to yield information on thermal conductivity of a pressurized sample. LÄS MER
9. Thermal Conductivity of Hygroscopic Foams Based on Cellulose Nanomaterials
Sammanfattning : Biobased super-insulating materials could mitigate climate change by minimizing the use of petroleum-based materials, creating artificial carbon sinks and minimizing the energy needed to maintain pleasant interior conditions. Cellulose nanomaterials (CNM) produced from abundantly available cellulose sources constitute versatile, highly anisotropic raw materials with tunable surface chemistry and high strength. LÄS MER
10. Proton conductivity in acceptor-doped lanthanide based pyrochlore oxides
Sammanfattning : A high interest in developing new materials for SOFC applications in the temperature range of approximately 200–500 C has been growing lately. The lower activation energies for proton (H+) mobility can give higher conductivity in this temperature range. LÄS MER