Sökning: "xenon"

Visar resultat 1 - 5 av 47 avhandlingar innehållade ordet xenon.

  1. 1. Predicting Xenon Oscillations in PWRs using Intrusive Reduced Order Modelling

    Författare :Kristoffer Pedersen; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Reduced Order Modeling; Modal Decomposition; Multi-Group Diffusion Theory; Xenon Oscillations;

    Sammanfattning : The increasing presence of intermittent energy sources in the Swedish electricity grid necessitates a transition of Swedish nuclear reactors from constant base load operation to load-following mode. However, such changes in power can induce xenon oscillations, a phenomenon that poses operational challenges and the risk of fuel damage. LÄS MER

  3. 2. Photoelectron Spectroscopy on Atoms, Molecules and Clusters : The Geometric and Electronic Structure Studied by Synchrotron Radiation and Lasers

    Författare :Torbjörn Rander; Olle Björneholm; Gunnar Öhrwall; Maxim Tchaplyguine; Matthias Neeb; Uppsala universitet; []
    Nyckelord :Atomic and molecular physics; Free clusters; Electron spectroscopy; Doped clusters; Laser excitation; Alkali metals; Electronic structure; Geometric structure; X-ray photoelectron spectroscopy XPS ; Resonant Auger spectroscopy RAS ; Near-threshold x-ray absorption fine structure NEXAFS ; Ultraviolet photoelectron spectroscopy UPS ; Detuning; Ultra-fast dissociation UFD ; Sodium; Potassium; Oxygen; Bromomethane; Argon; Xenon; Krypton; Molecular field splitting; Core hole lifetime; Core excitation; Atom- och molekylfysik;

    Sammanfattning : Atoms, molecules and clusters all constitute building blocks of macroscopic matter. Therefore, understanding the electronic and geometrical properties of such systems is the key to understanding the properties of solid state objects. LÄS MER

  4. 3. Single-photon multiple ionisation of atoms and molecules investigated by coincidence spectroscopy : Site-specific effects in acetaldehyde and carbon dioxide

    Författare :Sergey Zagorodskikh; Raimund Feifel; Vitali Zhaunerchyk; Melanie Mucke; Maria Novella Piancastelli; Tom Field; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; acetaldehyde; carbon dioxide; xenon; electron correlation; double ionisation; triple ionisation; core-valence ionisation; site-specific Auger decay; multiple Auger decay; branching ratios; site-specific photodissociation; molecular rearrangement; time-of-flight multi-electron-ion coincidence spectroscopy; synchrotron radiation; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this thesis, multiple ionisation processes of free atoms and molecules upon single photon absorption are studied by means of a versatile multi-electron-ion coincidence spectroscopy method based on a magnetic bottle, primarily in combination with synchrotron radiation. The latter offered the possibility to access not only valence but also core levels, revealing processes, which promote the target systems into different charge states. LÄS MER

  5. 4. Ventilation of the Paranasal Sinuses. A study using the 133-Xenon Washout Technique

    Författare :Bo Paulsson; Lund Institutionen för kliniska vetenskaper; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; auditive system and speech; single photon emission computed tomography; paranasal sinuses; ventilation; 133-xenon; chronic sinusitis; nose-sinus model; endoscopic sinus surgery; oxymetazoline; Otorhinolaryngology; Otorinolaryngologi; audiologi; hörsel- och talorganen; audiology;

    Sammanfattning : A noninvasive 133-xenon washout technique was used to evaluate the ventilation of the paranasal sinuses in healthy subjects and in patients with sinus disease. A mixture of air and 133-xenon is insufflated into the nasal cavities and passage into the sinuses is facilitated by a pressure increase created by letting the subjects inflate a balloon. LÄS MER

  7. 5. High-sensitivity Radioactive Xenon Monitoring and High-accuracy Neutron-proton Scattering Measurements

    Författare :Cecilia Johansson; Jan Blomgren; Nils Olsson; Allena Opper; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; Monte Carlo simulations; MCNP; xenon detection; detector response; neutron detection; elastic scattering; differential cross section; Kärnfysik; Nuclear physics; Kärnfysik;

    Sammanfattning : Two aspects of applied nuclear physics have been studied in this thesis; Monte Carlo simulations for high-sensitivity monitoring of radioactive xenon and high-accuracy neutron-proton scattering measurements for neutron physics applications and fundamental physics. The Monte Carlo simulations have been performed for two systems for detection of radioactive xenon, using the MCNP code. LÄS MER