TY - THES A1 - Kulow, Anicó T1 - Spatial Resolved Dispersive X-Ray Absorption Spectroscopy and Coded Aperture X-Ray Fluorescence Imaging N2 - One aim of this work was the development of a new setup for time- and laterally resolved XAFS measurements, based on the pronciple of dispersive XAFS. This setup is scanning free, stable, inexpensive, and straightforward to adjust for probing different elements. The second part of this work describes the impelemntation of a method for full-field X-ray fluorescence imaging with coded apertures. Expensive and complicated X-ray otpics, that are usually used for full-field imaging, are replaced with a coded aperture that consists of many pinholes drilled in an X-ray opaque material. Coded apertures are inexpensive to fabricate, energy independent and easy to use. The working principle is the same as with a pinhole camera, but the multiple holes allow a higher photon flux compared to a single pinhole or even a polycalippary optic, thus alowwing the reduction of measurement time. KW - X-ray fluorescence imaging KW - Coded Apertures KW - X-ray absorption spectroscopy KW - Synchrotron PY - 2021 SP - 1 EP - 175 CY - Berlin AN - OPUS4-52054 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kulow, Anicó T1 - Full field X-ray fluorescence imaging with coded apertures N2 - Our aim is to develop a simple and inexpensive method for full field X-ray fluorescence imaging.We combine an energy-dispersive array detector with a coded aperture to obtain high resolution images. To obtain the information from the recorded image a reconstruction step is necessary. The reconstruction methods we have developed, were tested on simulated data and then applied to experimental data. The first tests were carried out at the BAMline @ BESSY II. This method enables the simultaneous detection of multiple elements, which is important e.g. in the field of catalysis. T2 - CONEXS 2020 CY - Newcastle, UK DA - 18.02.2020 KW - X-ray fluorescence spectroscopy KW - Coded apertures KW - Imaging KW - Iterative reconstruction PY - 2020 AN - OPUS4-50461 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kulow, Anicó A1 - de Oliveira Guilherme Buzanich, Ana A1 - Reinholz, Uwe A1 - Emmerling, Franziska A1 - Hampel, S. A1 - Fittschen, UEA A1 - Streli, C. A1 - Radtke, Martin T1 - Reconstruction for coded aperture full-field x-ray fluorescence imaging N2 - X-ray fluorescence imaging is a well-established tool in materials characterization. In this work, we present the adaption of coded aperture imaging to full-field X-ray fluorescence imaging at the synchrotron. Coded aperture imaging has its origins in astrophysics, and has several advantages: Coded apertures are relatively easy to fabricate, achromatic, allow a high photon throughput, and high angular acceptance. Coded aperture imaging is a two-step-process, consisting of the measurement process and a reconstruction step. Different programs have been written, for the raytracing/forward projection and the reconstruction. Experiments with coded aperture in combination with a Color X-ray Camera and an energy-dispersive area detector, have been conducted at the BAMline. Measured samples were successfully reconstructed, and gave a 9.1-fold increase in count rate compared to a polycapillary optic. KW - Synchrotron KW - BAMline KW - Coded Aperture PY - 2022 SN - 1097-0002 VL - 65 SP - 57 EP - 70 PB - Cambridge University Press CY - Cambridge AN - OPUS4-56350 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -