Sökning: "Helium"
Visar resultat 11 - 15 av 124 avhandlingar innehållade ordet Helium.
11. Hyperpolarized 3He-diffusion MRI in evaluation of lung structure in emphysema. Validation and development of the method
Sammanfattning : Abstract COPD is a major cause of chronic morbidity and mortality throughout the world. It is a preventable and treatable disease. Smoking is the most commonly encountered risk factor for COPD and the habit now unfortunately starts at earlier ages than before. LÄS MER
12. Molecular Beam Studies of Ice Surface Properties
Sammanfattning : .... LÄS MER
13. Ergonomics of Breathing Apparatus, with Special Reference to Work of Breathing, Dead Space and Breathing Resistance
Sammanfattning : A breathing apparatus is a very useful device. It allows people to breathe relatively freely while entering environments that otherwise would be impenetrable such as extreme altitudes, smoke filled buildings, ocean depths and the surface of the moon. However, a breathing apparatus does have some disadvantages. LÄS MER
14. Towards a relativistically covariant many-body perturbation theory - With numerical implementation to helium-like ions
Sammanfattning : The experimental results for simple atomic systems have become more and more accurate and in order to keep up with the experimental achievements the theoretical procedures have to be refined. Recent accurate experimental results obtained for helium-like ions in the low- and moderate-Z regions proclaim the importance of theoretical calculations that combines relativistic, QED and electron correlation effects. LÄS MER
15. Helium in CERMET fuel - binding energies and diffusion
Sammanfattning : This thesis presents a first principle approach to model helium diffusionand retention in molybdenum. Results from electron structure calculations within the framework of density functional theory are used to assess parameters in a rate theory model. LÄS MER