The Experts below are selected from a list of 495819 Experts worldwide ranked by ideXlab platform
Günter Marx - One of the best experts on this subject based on the ideXlab platform.
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Analytical X-Ray Microscopy on Psaronius sp. - A Contribution to Permineralization Process Studies
Mikrochimica Acta, 2000Co-Authors: Dagmar Dietrich, Ronny Rößler, Georg Frosch, Günter MarxAbstract:290 Million years old petrifactions from the Lower Permian Rotliegend of Chemnitz were examined by analytical X-Ray Microscopy to determine their chemical composition. Mappings show the inhomogeneous distribution of the involved elements, which may reflect the former plant anatomy, as well as some contemporaneous processes of permineralization (with silica and fluorite) and agate-formation. Most prominent advantages of the analytical X-Ray Microscopy are the low preparation expense of the museum samples, the analysis scanning range and the X-Ray spot diameter suitable with the dimension of the fossil plants.
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Analytical X-Ray Microscopy on Psaronius sp. – A Contribution to Permineralization Process Studies
Microchimica Acta, 2000Co-Authors: Dagmar Dietrich, Ronny Rößler, Georg Frosch, Günter MarxAbstract:290 Million years old petrifactions from the Lower Permian Rotliegend of Chemnitz were examined by analytical X-Ray Microscopy to determine their chemical composition. Mappings show the inhomogeneous distribution of the involved elements, which may reflect the former plant anatomy, as well as some contemporaneous processes of permineralization (with silica and fluorite) and agate-formation. Most prominent advantages of the analytical X-Ray Microscopy are the low preparation expense of the museum samples, the analysis scanning range and the X-Ray spot diameter suitable with the dimension of the fossil plants.
G. Schmahl - One of the best experts on this subject based on the ideXlab platform.
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A monochromator for scanning X-Ray Microscopy beamlines at third-generation synchrotron light sources
Journal of Synchrotron Radiation, 1996Co-Authors: A. Irtel Von Brenndorff, Dietbert Rudolph, B. Niemann, G. SchmahlAbstract:A concept for a plane-grating monochromator for use at scanning X-Ray Microscopy beamlines at third-generation synchrotron light sources is presented. The design of the monochromator is optimized for a scanning transmission X-Ray Microscopy beamline at BESSY II. Ray-tracing calculations are presented which include geometric aberrations of the optics used in the beamline.
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X-Ray Microscopy studies of aqueous colloid systems
Progress in Colloid & Polymer Science, 1Co-Authors: J. Thieme, J. Niemeyer, Peter Guttmann, Thomas Wilhein, Dietbert Rudolph, G. SchmahlAbstract:X-Ray Microscopy is capable of imaging objects with a higher resolution than light Microscopy. The reason is the shorter wavelength of X-Rays compared to visible light. Up to now, the smallest structures that can be visualized are about 30 nm in size. It is possible to image objects directly in their aqueous environment without preparational procedures like drying, staining, etc. In the wavelength range of 2.4 nm ⩽ λ ⩽ 4.5 nm water absorbs x-radiation weakly compared to the absorption of other materials like alumino silicates, iron oxides or organic materials. This yields a natural contrast mechanism for the imaging of structures in their aqueous environment. Studies of aqueous colloidal systems demonstrate the abilities of X-Ray Microscopy. The aggregation of hematite particles under the influence of divalent cations (Ca2+) is investigated. The dependence of the size and the shape of the aggregates on the amount of added Ca2+ is directly visualized.
Martin V. Holt - One of the best experts on this subject based on the ideXlab platform.
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Time-Resolved X-Ray Microscopy for Materials Science
Annual Review of Materials Research, 2019Co-Authors: Haidan Wen, Mathew J. Cherukara, Martin V. HoltAbstract:X-Ray Microscopy has been an indispensable tool to image nanoscale properties for materials research. One of its recent advances is extending microscopic studies to the time domain to visualize the...
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Time-resolved X-Ray Microscopy for materials science.
arXiv: Mesoscale and Nanoscale Physics, 2018Co-Authors: Haidan Wen, Mathew J. Cherukara, Martin V. HoltAbstract:X-Ray Microscopy has been an indispensable tool to image nanoscale properties for materials research. One of its recent advances is to extend microscopic studies to the time domain for visualizing the dynamics of nanoscale phenomena. Large-scale X-Ray facilities have been the powerhouse of time-resolved X-Ray Microscopy. Their upgrades including a significant reduction of the X-Ray emittance at storage rings and fully coherent ultrashort X-Ray pulses at free electron lasers, will lead to new developments in instrumentation and open new scientific opportunities for X-Ray imaging of nanoscale dynamics with the simultaneous attainment of unprecedentedly high spatial and temporal resolutions. This review presents recent progress in and the outlook for time-resolved X-Ray Microscopy in the context of ultrafast nanoscale imaging and its applications to condensed matter physics and materials science.
Dagmar Dietrich - One of the best experts on this subject based on the ideXlab platform.
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Analytical X-Ray Microscopy on Psaronius sp. - A Contribution to Permineralization Process Studies
Mikrochimica Acta, 2000Co-Authors: Dagmar Dietrich, Ronny Rößler, Georg Frosch, Günter MarxAbstract:290 Million years old petrifactions from the Lower Permian Rotliegend of Chemnitz were examined by analytical X-Ray Microscopy to determine their chemical composition. Mappings show the inhomogeneous distribution of the involved elements, which may reflect the former plant anatomy, as well as some contemporaneous processes of permineralization (with silica and fluorite) and agate-formation. Most prominent advantages of the analytical X-Ray Microscopy are the low preparation expense of the museum samples, the analysis scanning range and the X-Ray spot diameter suitable with the dimension of the fossil plants.
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Analytical X-Ray Microscopy on Psaronius sp. – A Contribution to Permineralization Process Studies
Microchimica Acta, 2000Co-Authors: Dagmar Dietrich, Ronny Rößler, Georg Frosch, Günter MarxAbstract:290 Million years old petrifactions from the Lower Permian Rotliegend of Chemnitz were examined by analytical X-Ray Microscopy to determine their chemical composition. Mappings show the inhomogeneous distribution of the involved elements, which may reflect the former plant anatomy, as well as some contemporaneous processes of permineralization (with silica and fluorite) and agate-formation. Most prominent advantages of the analytical X-Ray Microscopy are the low preparation expense of the museum samples, the analysis scanning range and the X-Ray spot diameter suitable with the dimension of the fossil plants.
H.f. Poulsen - One of the best experts on this subject based on the ideXlab platform.
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Multi scale hard X-Ray Microscopy
Current Opinion in Solid State and Materials Science, 2020Co-Authors: H.f. PoulsenAbstract:Abstract The structure of crystalline materials is typically organised hierarchically on several length scales. Hard X-Ray Microscopy is presented as a collection of modalities that allows to zoom into a mm-sized sample to acquire 3D maps of any embedded region and at essentially all relevant length scales. For coarse mapping of grains, their orientations and average stress state diffraction based tomography methods can sample thousands of grains with a resolution of 2 µm. At the 100 nm scale, domains and dislocations and their associated strain fields can be visualised by diffraction Microscopy. Similar to dark field electron Microscopy, diffraction and imaging can be combined in several ways. For the ultimate resolution, a bulk version of coherent diffraction imaging is introduced. Hard X-Ray Microscopy is optimised for acquisition of 3D movies: directly visualising the structural changes during nucleation and growth, deformation or damage. The state of art is provided along with examples of use. I discuss how hard X-Ray Microscopy studies can enable the formulation and validation of improved multiscale models that account for the entire heterogeneity of materials.
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Dark field X-Ray Microscopy for studies of recrystallization
2015Co-Authors: S. R. Ahl, H. Simons, A. C. Jakobsen, Y. B. Zhang, F. Stohr, D. Juul Jensen, H.f. PoulsenAbstract:We present the recently developed technique of Dark Field X-Ray Microscopy that utilizes the diffraction of hard X-Rays from individual grains or subgrains at the (sub)micrometre-scale embedded within mm-sized samples. By magnifying the diffracted signal, 3D mapping of orientations and strains inside the selected grain is performed with an angular resolution of 0.005 and a spatial resolution of 200 nm. Furthermore, the speed of the measurements at high-intensity synchrotron facilities allows for fast non-destructive in situ determination of structural changes induced by annealing or other external influences. The capabilities of Dark Field X-Ray Microscopy are illustrated by examples from an ongoing study of recrystallization of 50% cold-rolled A11050 specimens
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Dark-field X-Ray Microscopy for multiscale structural characterization
Nature Communications, 2015Co-Authors: H. Simons, A. King, Wolfgang Ludwig, C. Detlefs, W. Pantleon, S. Schmidt, I. Snigireva, A. Snigirev, H.f. PoulsenAbstract:Many physical and mechanical properties of crystalline materials depend strongly on their internal structure, which is typically organized into grains and domains on several length scales. Here we present dark-field X-Ray Microscopy; a non-destructive Microscopy technique for the three-dimensional mapping of orientations and stresses on lengths scales from 100 nm to 1mm within embedded sampling volumes. The technique, which allows 'zooming' in and out in both direct and angular space, is demonstrated by an annealing study of plastically deformed aluminium. Facilitating the direct study of the interactions between crystalline elements is a key step towards the formulation and validation of multiscale models that account for the entire heterogeneity of a material. Furthermore, dark-field X-Ray Microscopy is well suited to applied topics, where the structural evolution of internal nanoscale elements (for example, positioned at interfaces) is crucial to the performance and lifetime of macro-scale devices and components thereof
