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During the measurement campaign FROST (FReezing Of duST), LACIS (Leipzig Aerosol Cloud Interaction Simulator) was used to investigate the immersion freezing behavior of size selected, coated and uncoated Ari-zona Test Dust (ATD) particles with a mobility diameter of 300 nm. Particles were coated with succinic acid (C 4 H 6 O 4), sulfuric acid (H 2 SO 4) and(More)
Seven different instruments and measurement methods were used to examine the immersion freezing of bacterial ice nuclei from Snomax ® (hereafter Snomax), a product containing ice-active protein complexes from non-viable Pseudomonas syringae bacteria. The experimental conditions were kept as similar as possible for the different measurements. Of the(More)
Kaolinite particles from two different sources (Fluka and Clay Minerals Society (CMS)) were examined with respect to their ability to act as ice nuclei (IN). This was done in the water-subsaturated regime where often de-position ice nucleation is assumed to occur, and for water-supersaturated conditions, i.e., in the immersion freezing mode. Measurements(More)
IGBT power modules used in traction applications undergo large load variations. Thermo-mechanically induced stress then leads to material fatigue which limits the module's lifetime. In this paper a method is presented for non-destructively quantifying the chip solder degradation during a power cycling experiment. The method is based on measuring the cooling(More)
Increasing operating voltages of insulated gate bipolar transistor (IGBT) modules results in higher demands on electrical insulation capabilities as well as partial discharge resistance. This paper discusses the insulation failure modes observed in high voltage power modules; most critical are water trees, partial discharge (PD) and electrical trees.(More)
To enable smaller and more cost efficient inverter designs, new power modules are designed for low losses, reliable operation at high temperature, high current and high switching frequencies. The IGBT module design presented in this paper features large silicon active area for low on-state losses, good internal temperature distribution, high current(More)