Search Results
Perspectives on the future of ice nucleation research: Research needs and Unanswered questions identified from two international workshops
2017, Coluzza, Ivan, Creamean, Jessie, Rossi, Michel J., Wex, Heike, Alpert, Peter Aaron, Bianco, Valentino, Boose, Yvonne, Dellago, Christoph, Felgitsch, Laura, Fröhlich-Nowoisky, Janine, Herrmann, Hartmut, Jungblut, Swetlana, Kanji, Zamin A., Menzl, Georg, Moffett, Bruce, Moritz, Clemens, Mutzel, Anke, Pöschl, Ulrich, Schauperl, Michael, Scheel, Jan, Stopelli, Emiliano, Stratmann, Frank, Grothe, Hinrich, Schmale, David G.
There has been increasing interest in ice nucleation research in the last decade. To identify important gaps in our knowledge of ice nucleation processes and their impacts, two international workshops on ice nucleation were held in Vienna, Austria in 2015 and 2016. Experts from these workshops identified the following research needs: (1) uncovering the molecular identity of active sites for ice nucleation; (2) the importance of modeling for the understanding of heterogeneous ice nucleation; (3) identifying and quantifying contributions of biological ice nuclei from natural and managed environments; (4) examining the role of aging in ice nuclei; (5) conducting targeted sampling campaigns in clouds; and (6) designing lab and field experiments to increase our understanding of the role of ice-nucleating particles in the atmosphere. Interdisciplinary teams of scientists should work together to establish and maintain a common, unified language for ice nucleation research. A number of commercial applications benefit from ice nucleation research, including the production of artificial snow, the freezing and preservation of water-containing food products, and the potential modulation of weather. Additional work is needed to increase our understanding of ice nucleation processes and potential impacts on precipitation, water availability, climate change, crop health, and feedback cycles.
Experimental Hall electron mobility of bulk single crystals of transparent semiconducting oxides
2021, Galazka, Zbigniew, Irmscher, Klaus, Pietsch, Mike, Ganschow, Steffen, Schulz, Detlev, Klimm, Detlef, Hanke, Isabelle M., Schroeder, Thomas, Bickermann, Matthias
We provide a comparative study of basic electrical properties of bulk single crystals of transparent semiconducting oxides (TSOs) obtained directly from the melt (9 compounds) and from the gas phase (1 compound), including binary (β-Ga2O3, In2O3, ZnO, SnO2), ternary (ZnSnO3, BaSnO3, MgGa2O4, ZnGa2O4), and quaternary (Zn1−xMgxGa2O4, InGaZnO4) systems. Experimental outcome, covering over 200 samples measured at room temperature, revealed n-type conductivity of all TSOs with free electron concentrations (ne) between 5 × 1015 and 5 × 1020 cm−3 and Hall electron mobilities (μH) up to 240 cm2 V−1 s−1. The widest range of ne values was achieved for β-Ga2O3 and In2O3. The most electrically conducting bulk crystals are InGaZnO4 and ZnSnO3 with ne > 1020 cm−3 and μH > 100 cm2 V−1 s−1. The highest μH values > 200 cm2 V−1 s−1 were measured for SnO2, followed by BaSnO3 and In2O3 single crystals. In2O3, ZnO, ZnSnO3, and InGaZnO4 crystals were always conducting, while others could be turned into electrical insulators.