Intro -- Vorwort -- List of figures -- List of tables -- Nomenclature -- Abstract -- Zusammenfassung -- Chapter 1 Introduction -- Chapter 2 State of the art and basic knowledge -- 2.1 Definition and fundamentals of fine bubbles -- 2.2 Hydrodynamics and mass transfer in bubbly flows -- 2.3 Suitable reactor systems and generation principles forfine bubble aeration -- Chapter 3 Experimental setups and procedure -- 3.1 Proof of stability for ultrafine bubbles in aqueousliquids -- 3.2 Three reactor setups to evaluate the performance usingfine bubble aeration -- 3.3 Setups for investigating local mass transfer effects atmicroscale bubbles -- Chapter 4 Measurement techniques -- 4.1 Nanoparticle Tracking Analysis -- 4.2 Laser induced fluorescence -- 4.3 Confocal laser scanning microscopy -- 4.4 Determination of the gas hold-up from endoscopicmeasurements -- Chapter 5 Experimental results and discussion -- 5.1 Proof of stability for ultrafine bubbles in aqueousliquids -- 5.2 Evaluation and comparison of fine bubble aeratedreactor concepts -- 5.3 Characterization of the membrane aerated stirredtank reactor concept -- 5.4 Fundamental mass transfer characteristics ofmicroscale bubbles -- Chapter 6 Conclusion -- References -- Appendix A -- Appendix B -- Appendix C.