Sökning: "zone plates"

Visar resultat 1 - 5 av 35 avhandlingar innehållade orden zone plates.

  1. 1. Zone Plates for Hard X-Ray Free-Electron Lasers

    Författare :Daniel Nilsson; Ulrich Vogt; Thomas Tschentscher; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; X-ray optics; Zone plates; XFEL; x-rays; free-electron laser; heat transfer;

    Sammanfattning : Hard x-ray free-electron lasers are novel sources of coherent x-rays with unprecedented brightness and very short pulses. The radiation from these sources enables a wide range of new experiments that were not possible with previous x-ray sources. Many of these experiments require the possibility to focus the intense x-ray beam onto small samples. LÄS MER

  3. 2. Nanofabrication of Zone Plates for Hard X-Ray Free-Electron Lasers

    Författare :Fredrik Uhlén; Ulrich Vogt; Thomas Wilhein; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; X-ray optics; Zone plates; Nanofabrication; X-ray free-electron lasers; Fysik; Physics;

    Sammanfattning : This Thesis describes the development of hard X-ray zone plates intended for focusing radiation at X-ray free-electron lasers (XFELs). XFELs provide unprecedented brightness and zone plates which are put in the intense X-ray beam are at risk of being damaged. LÄS MER

  4. 3. Separation of Proteins with Capillary Electrophoresis in Coated Capillaries with and without Electroosmosis : Studies on Zone Broadening and Analytical Performances

    Författare :Sheila Mohabbati; Douglas Westerlund; Bo Karlberg; Uppsala universitet; []
    Nyckelord :Pharmaceutical chemistry; Capillary electrophoresis; capillary coatings; proteins; zone broadening; zone sharpening; efficiency; resolution; protein-surface adsorption; protein-buffer interaction; analytical performance; Farmaceutisk kemi;

    Sammanfattning : Proteins have such structural features that they may interact with different types of surfaces by all possible forces, i.e., electrostatic, hydrogen bonding, hydrophobic. In this thesis two different types of coatings for fused silica capillaries aimed to eliminate such interactions have been studied. LÄS MER

  5. 4. High-Aspect Ratio Nanofabrication for Hard X-Ray Zone Plates

    Författare :Karolis Parfeniukas; Ulrich Vogt; Hans Hertz; Anne Sakdinawat; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nanofabrication; x-ray optics; zone plate; tungsten; silicon; reactive ion etching; metal-assisted chemical etching; Ronchi test; Fysik; Physics;

    Sammanfattning : Hard x-ray nanoimaging enables structural investigations of new materials for many applications. For high-resolution experiments, zone plate x-ray optics are commonly chosen.Two methods of zone plate nanofabrication are presented in this thesis.Zone plates are circular diffraction gratings with radially decreasing grating period. LÄS MER

  7. 5. Metal-assisted chemical etching for nanofabrication of hard X-ray zone plates

    Författare :Rabia Akan; Ulrich Vogt; Muhammet Toprak; Carmen Vogt; Lucia Romano; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; metal-assisted chemical etching; zone plate; high-aspect ratio; silicon; nanostructures; Material and Nano Physics; Material- och nanofysik; Optik och fotonik; Optics and Photonics;

    Sammanfattning : Hard X-ray scanning microscopes, or nanoprobes, make it possible to image samples and probe their chemical, elemental and structural properties at nanoscale resolution. This is enabled by the use of nanofocusing optics. Commonly used optics in nanoprobes for high resolution X-ray experiments are zone plates. LÄS MER