Sökning: "neutron imaging"
Visar resultat 1 - 5 av 24 avhandlingar innehållade orden neutron imaging.
1. X-ray and neutron μCT of biomedical samples: from image acquisition to quantification
Sammanfattning : Even though the validity of x-ray computed tomography in the analysis of biomedical samples is nowadays undisputed, the more recent imaging techniques and more advanced instruments (such as synchrotrons) are still relatively unknown to many medical doctors that could benefit from them.The doctoral work presented in this thesis joins a collective effort from the imaging community to demonstrate potential applications of advanced x-ray and neutron imaging methods to preclinical medical research, with the hope of contributing to reach a “critical mass” in the medical community and in the public opinion as well. LÄS MER
2. Dosimetry and radiation quality in fast-neutron radiation therapy : A study of radiation quality and basic dosimetric properties of fast-neutrons for external beam radiotherapy and problems associated with corrections of measured charged particle cross-sections
Sammanfattning : The dosimetric properties of fast-neutron beams with energies ≤80 MeV were explored using Monte Carlo techniques. Taking into account transport of all relevant types of released charged particles (electrons, protons, deuterons, tritons, 3He and α particles) pencil-beam dose distributions were derived and used to calculate absorbed dose distributions. LÄS MER
3. Investigation on the self-healing capabilties of asphaltic materials using neutron imaging
Sammanfattning : Bitumen acts as a binding agent in asphalt mixtures where it binds the aggregates together. It is known for its potential to heal small cracks and recover its mechanical properties under the right conditions. Though this self-healing property is known, there is currently a lack of knowledge about the mechanisms that drive the process. LÄS MER
4. Bone structure characterisation using neutron scattering techniques
Sammanfattning : Bones have unique mechanical properties that originate from their main constituents: mineral, in the form of hydroxyapatite (HAp) crystals, and collagen type-I. The stiffness of the HAp mineral combined with the flexibility of collagen, and their intricate hierarchical arrangement from the smallest individual building blocks to the organ level, result in a composite tissue with a remarkable ability to withstand complex loading scenarios. LÄS MER
5. Dosimetry Studies of Different Radiotherapy Applications using Monte Carlo Radiation Transport Calculations
Sammanfattning : Developing radiation delivery systems for optimisation of absorbed dose to the target without normal tissue toxicity requires advanced calculations for transport of radiation. In this thesis absorbed dose and fluence in different radiotherapy applications were calculated by using Monte Carlo (MC) simulations. LÄS MER