Search for dissertations about: "liquid helium"

Showing result 6 - 10 of 27 swedish dissertations containing the words liquid helium.

  2. 6. Applications of Soft X-Ray Spectroscopy

    Author : Conny Såthe; Jan-Erik Rubensson; Joseph Nordgren; Marcus Agåker; Raimund Feifel; Marc Simon; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Abstract : Soft X-ray emission spectroscopy is an old experimental technique that has seen a strong revival since the advent of new high brilliance soft X-ray sources in the shape of synchrotrons.  This thesis covers a range of applications where soft x-ray techniques have been applied. READ MORE

  4. 7. On-scalp MEG using high-Tc SQUIDs: Measuring brain activity with superconducting magnetometers

    Author : Christoph Pfeiffer; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high-Tc SQUID; neuroimaging; magnetoencephalography; localization; on-scalp MEG; sensor array; magnetometer;

    Abstract : This thesis describes work done towards realizing on-scalp magnetoencephalography (MEG) based on high critical temperature (high- T c) superconducting quantum interference device (SQUID) sensors. MEG is a non-invasive neuroimaging modality that records the magnetic fields produced by neural currents with good spatial and high temporal resolution. READ MORE

  5. 8. Protons, other Light Ions, and 60Co Photons : Study of Energy Deposit Clustering via Track Structure Simulations

    Author : Gloria Bäckström; Anders Ahnesjö; Nina Tilly; José M. Fernández-Varea; Niels Bassler; Uppsala universitet; []
    Keywords : Proton; light ion; Co-60 photon; track structure Monte Carlo code; clustering patterns of energy deposit; RBE; Medicinsk radiofysik; Medical Radiophysics;

    Abstract : Radiotherapy aims to sterilize cancer cells through ionization induced damages to their DNA whilst trying to reduce dose burdens to healthy tissues. This can be achieved to a certain extent by optimizing the choice of radiation to treat the patient, i.e. the types of particles and their energy based on their specific interaction patterns. READ MORE

  6. 9. Injection and Combustion of Alternative Fuels in Spark Ignited Direct Injection Engines

    Author : Lars Christian Riis Johansen; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gas fuel; direct injection; E85; stratified combustion; spark ignition; alternative fuels; optical measurements;

    Abstract : Increasingly stringent vehicle emission legislation necessitates increasingly efficient combustion engines. The use of direct injection in spark ignited engines improves engine efficiency and reduces CO2 emissions. READ MORE

  7. 10. Cerium as a quantum state probe for rare-earth qubits in a crystal

    Author : Jenny Karlsson; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Spectroscopy; Quantum Computing; Rare-earth-ion-doped crystals; Microscopy; Fysicumarkivet A:2015:Karlsson;

    Abstract : Rare-earth ions doped into a transparent crystal can have optically excited states with coherence times of milliseconds and hyperfine levels with coherence times of hours when cooled down to liquid helium temperatures. This makes them attractive for developing quantum computing hardware. READ MORE