Scientific Highlights
Discovery of new chemistry on aerosol surfaces
In a study published in Science, ambient-pressure X-ray photoelectron spectroscopy reveals spontaneous redox chemistry at solvating particle surfaces.
What you see is what you get: Automated particle detection without the false positives
A new algorithm by PSI researchers enables fast and reliable detection of spherical objects in images with a complex background.
PUBLISHED IN SCIENCE: A surface-promoted redox reaction occurs spontaneously on solvating inorganic aerosol surfaces
Ammonium sulfate has been used as a probe for aerosol particles and investigated in situ by means of ambient pressure X-ray photoelectron spectroscopy. Unexpectedly, when the particles start to absorb water, a spontaneous redox reaction leading to nitrogen and elemental sulfur takes place.
Neurodegenerative disease studied by cryogenic X-ray nanotomography
Hard X-ray cryo-tomography scanning of retina from healthy and inherited blindness specimen paves the way for correlative analysis after imaging at the cSAXS beamline.
Vastly Different Morphologies Dependent on the Growth Temperature
Lithium fluoride is an important material which is technologically exploited in spintronics and organic light emitting devices. It turns out that there is a vast difference between the morphologies of ultrathin lithium fluoride grown on the (100) facet of a silver single crystal. At room temperature dendrites are obtained while at elevated temperature lithium fluoride forms square islands. The system is an interesting model to study the crossover between diffusion limited aggregates and island growth.
Diamond gratings for XFEL amplitude-splitting delay line
A split-and-delay line for XFEL pulses has been built and successfully tested by a team of researchers at the Linac Coherent Light Source. Key X-ray optical elements are two diamond diffraction gratings made at the Paul Scherrer Institut that are used to split and later recombine the intense ultrashort X-ray laser pulses for time-resolved measurements.
Coexistence of structural and magnetic phases in van der Waals magnet CrI3
CrI3 has raised as an important system to the emergent field of two-dimensional van der Waals magnetic materials. However, it is still unclear why CrI3 which has a ferromagnetic rhombohedral structure in bulk, changed to anti-ferromagnetic monoclinic at thin layers. Here we show that this behaviour is due to the coexistence of both monoclinic and rhombohedral crystal phases followed by three magnetic transitions at TC1 = 61 K, TC2 = 50 K and TC3 = 25 K.
Take a deep breath. But how clean was the air?
The EU project, RI-URBANS, aims to improve air quality monitoring across Europe
Overview of SwissFEL dual-photocathode laser capabilities and perspectives for exotic FEL modes
SwissFEL is a compact, high-brilliance, soft and hard X-ray Free Electron Laser (FEL) facility laser composed of two parallel beam lines seeded by a common linear accelerator (LINAC), and a two-bunch photo-injector. For the injector, an innovative dual-photocathode laser scheme has been developed based on state-of-the-art Ytterbium femtosecond laser systems. We just published an overview of the the SwissFEL Photo Cathode Drive Lasers (PCDL) performance, pulse shaping capabilities as well as the versatility of the systems, which allow many different modes of operation of SwissFEL [1]. The full control over the SwissFEL electron bunch properties via the unique architecture of the PCDL will enable in the future the advent of more advanced FEL modes; these modes are, but not restricted to, the generation of single or trains of sub-fs FEL pulses, multi-color FEL and finally the generation of fully coherent X-ray pulses via laser-based seeding.
Glycation of collagen: Quantifying rates
Collagen is abundant in the connective tissue of human beings, e.g. in tendons, ligament and cornea. Glycation of collagen distorts its structure, renders the extracellular matrix stiff and brittle and at the same time lowers the degradation susceptibility thereby preventing renewal. Based on models and with parameters determined from experimental data, we describe the glycation of type 1 collagen in bovine pericardium derived bio-tissues upon incubation in glucose and ribose. We hope that this contributes to a better quantitative understanding of the effects of diabetes on collagen.