Paulus, Michael
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Publication Access status: Metadata only , (Sub-)Picosecond Surface Correlations of Femtosecond Laser Excited Al-Coated Multilayers Observed by Grazing-Incidence X-ray Scattering(2024); ; ; ; Bußmann, MichaelFemtosecond high-intensity laser pulses at intensities surpassing 1014 W/cm2 can generate a diverse range of functional surface nanostructures. Achieving precise control over the production of these functional structures necessitates a thorough understanding of the surface morphology dynamics with nanometer-scale spatial resolution and picosecond-scale temporal resolution. In this study, we show that single XFEL pulses can elucidate structural changes on surfaces induced by laser-generated plasmas using grazing-incidence small-angle X-ray scattering (GISAXS). Using aluminium-coated multilayer samples we distinguish between sub-picosecond (ps) surface morphology dynamics and subsequent multi-ps subsurface density dynamics with nanometer-depth sensitivity. The observed subsurface density dynamics serve to validate advanced simulation models representing matter under extreme conditions. Our findings promise to open new avenues for laser material-nanoprocessing and high-energy-density science.Source Type:Article2 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Metadata only , Salt induced slowdown of kinetics and dynamics during thermal gelation of egg-yolk(2024); ; We investigated the effect of the NaCl concentration (0.3–2M) on the structure and dynamics of hen egg yolk at room temperature and during thermal gelation at temperatures in the range of 66–90 °C utilizing low-dose x-ray photon correlation spectroscopy in ultra-small angle x-ray scattering geometry. With an increase in the salt concentration, we observe progressive structural and dynamic changes at room temperature, indicating the disruption of yolk components such as yolk-granules and yolk-plasma proteins. Temperature- and salt-dependent structural and dynamic investigations suggest a delay in the gel formation and aggregation of yolk low-density lipoproteins with increasing ionic strength. However, the time–temperature superposition relationship observed in all samples suggests an identical mechanism underlying protein aggregation–gelation with a temperature-dependent reaction rate. The sol–gel transition time extracted from kinetic and dynamic information follows Arrhenius’s behavior, and the activation energy (460 kJ/mol) is found to be independent of the salt concentration.Source Type:Article3 - Some of the metrics are blocked by yourconsent settings
Publication Access status: Metadata only , X-ray driven and intrinsic dynamics in protein gels(2023); ; ; Source Type:Article1
