A direct association between amber and dinosaur remains provides paleoecological insights

This work is licensed under a Creative Commons Attribution 4.0 International License.Hadrosaurian dinosaurs were abundant in the Late Cretaceous of North America, but their habitats remain poorly understood. Cretaceous amber is also relatively abundant, yet it is seldom found in direct stratigraphic association with dinosaur remains. Here we describe an unusually large amber specimen attached to a Prosaurolophus jaw, which reveals details of the contemporaneous paleoforest and entomofauna. Fourier-transform Infrared spectroscopy and stable isotope composition (H and C) suggest the amber formed from resins exuded by cupressaceous conifers occupying a coastal plain. An aphid within the amber belongs to Cretamyzidae, a Cretaceous family suggested to bark-feed on conifers. Distinct tooth row impressions on the amber match the hadrosaur’s alveolar bone ridges, providing some insight into the taphonomic processes that brought these remains together

On single bubble mass transfer in a volatile liquid

We consider single bubble mass transfer of an non-condensible gas into a volatile liquid phase in indus- trial conditions, as observed for example in hydrocarbons liquid phase oxidation processes. Instantaneous bubble size, shape and velocity are measured using image processing with a particle tracking method. The mass transfer rate nitrogen into hot and pressurized liquid cyclohexane is deduced from the bubble volume decrease rate and is compared to literature correlations valid under isothermal conditions. Experiments are performed in a pressurized reactor for P = 20 bar, 30° ≤ T ≤ 150°C and bubble Reynolds number Re = O(10—100). The analysis of bubble rise dynamics shows that the gas-liquid system studied can be considered as a clean system. The mass transfer results are found to follow isothermal correlations predictions excepted for ambient temperature for which liquid evaporation in bubbles is shown to be coupled with mass transfer. This phenomena seems to be a consequence of having a high Lewis number