Showing papers by "Joachim Schulz published in 2016"
Technical University of Berlin1, SLAC National Accelerator Laboratory2, Max Planck Society3, European XFEL4, Aarhus University5, Lund University6, National Science Foundation7, Fundamental Research on Matter Institute for Atomic and Molecular Physics8, German National Metrology Institute9, University of Hamburg10, Folkwang University of the Arts11, Kansas State University12
TL;DR: In this article, single Xe clusters are superheated using an intense optical laser pulse and the structural evolution is imaged with a single X-ray pulse, and the surface softening on the nanometre scale is resolved within 100 fs at the vacuum/sample interface.
Abstract: Single Xe clusters are superheated using an intense optical laser pulse and the structural evolution is imaged with a single X-ray pulse. Ultrafast surface softening on the nanometre scale is resolved within 100 fs at the vacuum/sample interface.
105 citations
TL;DR: First imaging results using a 2×2 stitched analyzer grating in a Talbot-Lau interferometer have been generated using a conventional polychromatic X-ray source, and the image quality and analysis confirm the high potential of the stitching method to increase the field of view considerably.
Abstract: Grating based X-ray differential phase contrast imaging (DPCI) allows for high contrast imaging of materials with similar absorption characteristics. In the last years' publications, small animals or parts of the human body like breast, hand, joints or blood vessels have been studied. Larger objects could not be investigated due to the restricted field of view limited by the available grating area. In this paper, we report on a new stitching method to increase the grating area significantly: individual gratings are merged on a carrier substrate. Whereas the grating fabrication process is based on the LIGA technology (X-ray lithography and electroplating) different cutting and joining methods have been evaluated. First imaging results using a 2×2 stitched analyzer grating in a Talbot-Lau interferometer have been generated using a conventional polychromatic X-ray source. The image quality and analysis confirm the high potential of the stitching method to increase the field of view considerably.
25 citations
TL;DR: This paper presents how a two-grating interferometer is incorporated into a commercially available nanotom m (GE Sensing and Inspection Technologies GmbH) μCT system to extend its capabilities toward phase contrast and intends to demonstrate superior contrast in spiders and Xysticus erraticus as well as the simultaneous visualisation of hard and soft tissues.
Abstract: X-ray imaging in the absorption contrast mode is an established method of visualising calcified tissues such as bone and teeth. Physically soft tissues such as brain or muscle are often imaged using magnetic resonance imaging (MRI). However, the spatial resolution of MRI is insufficient for identifying individual biological cells within three-dimensional tissue. X-ray grating interferometry (XGI) has advantages for the investigation of soft tissues or the simultaneous three-dimensional visualisation of soft and hard tissues. Since laboratory microtomography (μCT) systems have better accessibility than tomography set-ups at synchrotron radiation facilities, a great deal of effort has been invested in optimising XGI set-ups for conventional μCT systems. In this conference proceeding, we present how a two-grating interferometer is incorporated into a commercially available nanotom m (GE Sensing and Inspection Technologies GmbH) μCT system to extend its capabilities toward phase contrast. We intend to demonstrate superior contrast in spiders (Hogna radiata (Fam. Lycosidae) and Xysticus erraticus (Fam. Thomisidae)), as well as the simultaneous visualisation of hard and soft tissues. XGI is an imaging modality that provides quantitative data, and visualisation is an important part of biomimetics; consequently, hard X-ray imaging provides a sound basis for bioinspiration, bioreplication and biomimetics and allows for the quantitative comparison of biofabricated products with their natural counterparts.
10 citations
Uppsala University1, SLAC National Accelerator Laboratory2, European XFEL3, Arizona State University4, University of Rome Tor Vergata5, University of Hamburg6, Academy of Sciences of the Czech Republic7, Jožef Stefan Institute8, University of Melbourne9, Technical University of Berlin10, Max Planck Society11, National University of Singapore12
TL;DR: This paper presents two data sets from micron-sized cyanobacteria obtained at the Linac Coherent Light Source, containing a total of 199,000 diffraction patterns, requiring the development of new analysis methods and algorithms for studying structure and structural variability in large populations of cells and to create abstract models.
Abstract: Structural studies on living cells by conventional methods are limited to low resolution because radiation damage kills cells long before the necessary dose for high resolution can be delivered. X-ray free-electron lasers circumvent this problem by outrunning key damage processes with an ultra-short and extremely bright coherent X-ray pulse. Diffraction-before-destruction experiments provide high-resolution data from cells that are alive when the femtosecond X-ray pulse traverses the sample. This paper presents two data sets from micron-sized cyanobacteria obtained at the Linac Coherent Light Source, containing a total of 199,000 diffraction patterns. Utilizing this type of diffraction data will require the development of new analysis methods and algorithms for studying structure and structural variability in large populations of cells and to create abstract models. Such studies will allow us to understand living cells and populations of cells in new ways. New X-ray lasers, like the European XFEL, will produce billions of pulses per day, and could open new areas in structural sciences.
7 citations
TL;DR: A new method to acoustically inject samples for serial femtosecond crystallography into the focus of free-electron lasers can drastically reduce the sample consumption of this method.
1 citations