Sökning: "x-rays"

Visar resultat 6 - 10 av 191 avhandlingar innehållade ordet x-rays.

  1. 6. 3D nano-tomography using coherent X-rays

    Författare :Maik Kahnt; Lunds universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ptychography; Tomography; Phase reconstruction; X-ray microscopy;

    Sammanfattning : X-rays allow to non-destructively investigate biological, chemical or physical processes at the nano-scale. Their high penetration depth in matter allows to investigate samples even inside sample environments, which would be difficult with complementary methods such as transmission electron microscopy (TEM). LÄS MER

  2. 7. Magnetism and Structure of Thin 3d Transition Metal Films : XMCD and EXAFS using Polarized Soft X-Rays

    Författare :Anders Hahlin; Dimitri Arvanitis; Olof Karis; Claus Schneider; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; thin film; xmcd; exafs; anisotropy; coherence; circular polarization; magnetism; Fe; Co; Ag; Fysik; Physics; Fysik; Fysik; Physics;

    Sammanfattning : In this Thesis the magnetic and structural properties of thin epitaxial Fe, Co, and Ni films are discussed. Some of the in-situ prepared samples were used to characterize the degree of circular polarization of the newly installed beamline D1011 at MAX-lab. LÄS MER

  3. 8. Core-hole Clock Spectroscopy Using Hard X-rays : Exciting States in Condensed Matter

    Författare :Fredrik Johansson; Andreas Lindblad; Carla Puglia; Tomas Edvinsson; Marc Simon; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; core-hole clock; resonant Auger; XPS; black phosphorous; TMDC; perovskite; graphene; coincidences spectroscopy; synchrotron radiation; HAXPES;

    Sammanfattning : This thesis is about how electrons move from one place to another, that is charge transfer dynamics. Charge transfer dynamics is an important property governing chemical and physical changes that form the base for many applications such as electronics, optoelectronics and catalysis. LÄS MER

  4. 9. A multi-prism lens for hard X-Rays

    Författare :Björn Cederström; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; x-ray; optics; refractive; lens; mammography; synchrotron; Physics; Fysik;

    Sammanfattning : This thesis describes a new type of refractive lens for hardx-rays. It is shown that a linear array of prisms, slightlyinclined with respect to the optical axis, will form a linefocus at a certain distance from the lens. Hence, the namemulti-prism lens. LÄS MER

  5. 10. Effective use of X rays in diagnostic radiology : Guidance for the optimisation of image quality and absorbed dose in the patient by use of a Monte Carlo computational model of the imaging chain

    Författare :Michael Sandborg; Heang-Ping Chan; Linköpings universitet; []
    Nyckelord :MEDICINE; MEDICIN;

    Sammanfattning : The primary objective of this thesis is to give guidance for the reduction of absorbed dose in the patient and the improvement of image quality by the optimisation of the various parameters which control the performance of the radiological imaging system. The optimisation means that image quality (contrast in screen-film imaging and signal-to-noise ratio in digital imaging) is kept constant and combinations of operating parameters which yields the lowest mean absorbed dose in the patient is determined. LÄS MER