Interaction of Impact Liquid Drop With Splat in Spray Cooling

This study investigates the interaction between an impacting liquid drop and a splat generated on a solid prior to impact, focusing mainly on the wave production and propagation on the splat with low impact velocity. Using high-speed video, the wave generation concerning the effects of Weber number is observed and analyzed, including the first wave caused by drop kinematic energy, the secondary and tertiary capillary waves subjected to surface tension. Also, the wave propagation magnitude is discussed, the purpose of which is to provide a suitable method for predicting the wave diameter. Results show that the increasing of Weber number is slightly against the wave propagation, but this effect weakens gradually. The kinematic discontinuity theory devised for crown propagation can be applied to predict the wave propagation magnitude with an excellent agreement, for both the kinematic wave and the capillary wave. In addition, the propagation speed of the wave during the drop-splat interaction is also analyzed.

Continuity of European Languages from the Point of View of DNA Genealogy

The combination of linguistic and DNA Genealogy data indicates that the aboriginal Europeans, the Y Chromosome haplogroup I people were the Proto-Indo-Europeans and the Proto-Slavic speakers. In contact with newcomers of other language groups mixing took place. Either the newcomers were absorbed into the autochthonous Proto-Slavic community, or the native Proto-Slavic population was so effected by the immigrants that they lost their Slavic identity and formed a language, which remained Indo-European but no longer recognizable as specifically Slavic. The Kurgan Theory and the Pontic Steppe Theory of the Indo-European origin failed completely. The Neolithic Discontinuity Theory theory gives only a part of the necessary explanation. The Paleolithic Continuity Paradigm is superior to them, but it has to be adapted to the data presented by the DNA Genealogy about the timeframe and probable localities of past events.