Publications by authors named "Richard Nauber"

Unlabelled: Micro-and nanorobots have the potential to perform non-invasive drug delivery, sensing, and surgery in living organisms, with the aid of diverse medical imaging techniques. To perform such actions, microrobots require high spatiotemporal resolution tracking with real-time closed-loop feedback. To that end,  photoacoustic imaging has appeared as a promising technique for imaging microrobots in deep tissue with higher molecular specificity and contrast.

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Biohybrid micromotors are active microscopic agents consisting of biological and synthetic components that are being developed as novel tools for biomedical applications. By capturing motile sperm cells within engineered microstructures, they can be controlled remotely while being propelled forward by the flagellar beat. This makes them an interesting tool for reproductive medicine that can enable minimally invasive sperm cell delivery to the oocyte in vivo, as a treatment for infertility.

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Medical microrobotics is an emerging field that aims at non-invasive diagnosis and therapy inside the human body through miniaturized sensors and actuators. Such microrobots can be tethered (e.g.

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Zinc-air flow batteries provide a scalable and cost-efficient energy storage solution. However, the achieved power density depends on the local flow conditions of the zinc particle suspension in the electrochemical cell. Numerical modeling is challenging due to the complex multiphase fluid and the interaction of flow and electrochemistry.

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Flow batteries using suspension electrodes, e.g., zinc-air flow batteries (ZABs), have recently gained renewed interest as potential candidates for grid energy storage or mobile applications.

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The flow field of moving foams is relevant for basic research and for the optimization of industrial processes such as froth flotation. However, no adequate measurement technique exists for the local velocity distribution inside the foam bulk. We have investigated the ultrasound Doppler velocimetry (UDV), providing the first two-dimensional, non-invasive velocity measurement technique with an adequate spatial (10mm) and temporal resolution (2.

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Ultrasonic guided waves enable flow measurements under harsh conditions, which are important, for instance, to monitor and optimize industrial solidification processes. The usage of single mode waveguides overcomes the problem of overheating the transducers, but requires a mechanical scanning for imaging. A multimode waveguide can carry the information of an image, but a scrambling of the signals occurs due to multiple reflections at the waveguide's boundaries.

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Controllable magnetic fields can be used to optimize flows in technical and industrial processes involving liquid metals in order to improve quality and yield. However, experimental studies in magnetohydrodynamics often involve complex, turbulent flows and require planar, two-component (2c) velocity measurements through only one acoustical access. We present the phased array ultrasound Doppler velocimeter as a modular research platform for flow mapping in liquid metals.

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A high energy conversion and cost efficiency are keys for the transition to renewable energy sources, e.g., solar cells.

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