Sökning: "X-ray free-electron lasers"

Visar resultat 16 - 20 av 36 avhandlingar innehållade orden X-ray free-electron lasers.

  1. 16. Flash Diffractive Imaging in Three Dimensions

    Författare :Tomas Ekeberg; Janos Hajdu; Keith Nugent; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; X-ray; diffraction; mimivirus; three dimensional; phase retrieval; EMC; manifold embedding; CXI; FEL; free-electron laser; single particle; Physics with specialization in Biophysics; Fysik med inriktning mot biofysik;

    Sammanfattning : During the last years we have seen the birth of free-electron lasers, a new type of light source ten billion times brighter than syncrotrons and able to produce pulses only a few femtoseconds long. One of the main motivations for building these multi-million dollar machines was the prospect of imaging biological samples such as proteins and viruses in 3D without the need for crystallization or staining. LÄS MER

  3. 17. Structural studies of small viruses using an X-ray Free Electron Laser

    Författare :Anna Munke; Marvin Seibert; Dirk Hasse; Inger Andersson; Carl Caleman; Maria Selmer; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics with specialization in Biophysics; Fysik med inriktning mot biofysik;

    Sammanfattning : X-ray crystallography has since its introduction been the most successful technique for solving protein structures. Viruses however, often possess structural components such as fibrils, tails and envelopes that make them difficult or impossible to crystallize. LÄS MER

  4. 18. Toward Creating a Coherent, Next-Generation Light Source with special emphasis on nonlinear harmonic generation in single-pass, high-gain free-electron lasers

    Författare :Sandra G. Biedron; Lunds universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Visible and Ultraviolet Sources; Intense Particle Beams and Radiation Sources; Frequency Conversion; Free-Electron Lasers; Harmonic Generation; Physics; Fysik;

    Sammanfattning : There is a strong desire for short wavelength (~1 Å), short pulsewidth (.... LÄS MER

  5. 19. Towards Fast and Robust Algorithms in Flash X-ray single-particle Imaging

    Författare :Jing Liu; Stefan Engblom; Filipe Maia; Janos Hajdu; Helmut Grubmüller; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; X-ray Free Electron lasers XFELs ; 3D electron density determination; Machine learning; Image processing; High-performance computing; GPUs; Uncertainty quantification; X-ray single-particle Imaging; Flash X-ray single-particle diffraction Imaging FXI ; ; Physics with specialization in Biophysics; Fysik med inriktning mot biofysik;

    Sammanfattning : Modern X-ray Free Electron Laser (XFEL) technology provides the possibility to acquire a large number of diffraction patterns from individual biological nano-particles, including proteins, viruses, and DNA. Ideally, the collected data frames are high-quality single-particle diffraction patterns. LÄS MER

  7. 20. The Role of Molecular Heterogeneity in the Structural Dynamics of Aqueous Solutions

    Författare :Sharon Berkowicz; Fivos Perakis; Giulio Monaco; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Water; Aqueous solutions; X-ray scattering; X-ray photon correlation spectroscopy; Dynamic light scattering; kemisk fysik; Chemical Physics;

    Sammanfattning : The liquid-liquid critical point hypothesis suggests that liquid water exists in two liquid states with different local structures, so-called high- and low-density liquid (HDL, LDL). At ambient pressure water locally fluctuates between these two states, with the fluctuations becoming more pronounced as the liquid is supercooled. LÄS MER