Congratulations to Anahita Keshmiri on the Successful Defense of the Doctoral Thesis

On June 17, 2025, M.Sc. Anahita Keshmiri successfully defended her dissertation entitled "Sorption Behavior of Surfactants, Proteins, and Particles on Single-Bubble Interfaces in Ultrasonic Standing Waves."

The dissertation investigates the impact of low-intensity, low-frequency ultrasound on sorption processes at the interface of single gas bubbles. The aim is to bridge the gap between microscale fundamental phenomena and large-scale industrial applications. Surfactants, proteins, and particles are systematically analyzed in a standing ultrasonic field to understand the effects of mild, non-cavitating ultrasound on adsorption and attachment kinetics.

Using profile analysis tensiometry, image analysis, and micro-Particle Image Velocimetry, both local and global effects are examined in detail. While surfactants such as Triton X-100 show little response to ultrasound due to their rapid adsorption kinetics, proteins with slower adsorption behavior exhibit significant improvements under ultrasonic-induced microscale flows. In particle-laden systems, enhanced attachment efficiency was observed, attributed to targeted acoustic forces.

The findings demonstrate that low-intensity ultrasound can be effectively employed in systems with kinetic barriers, such as protein adsorption or particle attachment in flotation processes. These insights provide a solid foundation for the development of energy-efficient, sustainable technologies in areas such as water purification, biotechnology, and mineral processing.