The University of Shanghai for Science and Technology (USST), the Coburg University of Applied Sciences and Arts (CUASA) and the OTH Regensburg, University of Applied Sciences (OTHR) established an English taught international cooperative bachelor program in the area of Engineering Physics/Optoelectronics. Students from China study their first four semesters at USST. They continue their studies in Germany for the last three semesters, including an internship and a bachelor thesis, graduating with a Chinese and a German bachelor degree. Students from Germany study their third and fourth semester at USST to gain international experience. While the first cohort of Chinese students is currently in Germany, the second cohort of German students is in Shanghai. Up to now the feedback regarding this study program is completely positive, thus it is planned to develop it further.
With an acoustic levitator small particles can be aggregated near the nodes of a standing pressure field. Furthermore it is possible to atomize liquids on a vibrating surface. We used a combination of both mechanisms and atomized several liquids simultaneously, consecutively and emulsified in the ultrasonic field. Using a high-speed camera we observed the coagulation of the spray droplets into single large levitated droplets resolved in space and time. In case of subsequent atomization of two components the spray droplets of the second component were deposited on the surface of the previously coagulated droplet of the first component without mixing.
The kinetics of electrochemical reactions is controlled by diffusion processes of charge carriers across a boundary layer
between the electrode and the electrolyte, which result in a shielding of the electric field inside the electrolyte and a
concentration gradient across this boundary layer. In accumulators the diffusion rate determines the rather long time
needed for charging, which is a major drawback for electric mobility. This diffusion boundary can be removed by
acoustic streaming in the electrolyte induced by surface acoustic waves propagating of the electrode, which results in an
increase of the charging current and thus in a reduction of the time needed for charging.
For a quantitative study of the influence of acoustic streaming on the charge transport an electropolishing cell with
vertically oriented copper electrodes and diluted H<sub>3</sub>PO<sub>4</sub>-Propanol electrolytes were used. Lamb waves with various
excitation frequencies were exited on the anode with different piezoelectric transducers, which induced acoustic
streaming in the overlaying electrolytic liquid. An increase of the polishing current of up to approximately 100 % has
been obtained with such a set-up.