Scientific Highlights

Detailed characterization of the tooth and jaw structure and development among shark ancestors by synchrotron based X-ray tomographic microscopy at TOMCAT led an international team of researchers from the Naturalis Biodiversity Center in Leiden and the University of Bristol to the discovery that while teeth evolved once, complex dentitions have been gained and lost many times in evolutionary history.

The compounds known as ‘pyrazinacenes’ are simple, stable compounds that consist of a series of connected nitrogen-containing carbon rings. They are suitable for applications in electrochemistry or synthesis, as the researchers describe in the science journal Communications Chemistry. They were first designed, synthesized and chemically characterized in solution by the Hill team and carefully investigated by Scanning Tunneling Microscopy and Surface Chemical Analysis. The compounds have been shown to reversibly release and accept electrons and arrange themselves differently depending on the oxidation state. Interestingly, the oxidation and reduction reactions of the pyrazinacenes are not only affected by a chemical impulse, but can also be stimulated by light so they can be considered photo-redox active.

High-resolution XRF imaging of the specific metal distribution within wool fibers at the PHOENIX beamline gives insights into traditional oriental dyeing procedures.

During the past decade, scientists have put high effort to achieve sub-10 nm resolution in X-ray microscopy. Recent developments in high-resolution lithography-based diffractive optics, combined with the extreme stability and precision of the PolLux and HERMES scanning X-ray microscopes, resulted now in a so far unreached resolution of seven nanometers in scanning soft X-ray microscopy. Utilizing this highly precise microscopy technique with the X-ray magnetic circular dichroism effect, dimensionality effects in an ensemble of interacting magnetic nanoparticles can be revealed.