Tomoscopy Time Resolved Tomography for Dynamic Processes in Materials

The structure and constitution of opaque materials can be studied with X ray imaging methods such as 3D tomography. To observe the dynamic evolution of their structure and the distribution of constituents, for example, during processing, heating, mechanical loading, etc., 3D imaging has to be fast enough. In this paper, the recent developments of time resolved X ray tomography that have led to what one now calls tomoscopy are briefly reviewed A novel setup is presented and applied that pushes temporal resolution down to just 1 ms, that is, 1000 tomograms per second tps are acquired, while maintaining spatial resolutions of micrometers and running experiments for minutes without interruption. Applications recorded at different acquisition rates ranging from 50 to 1000 tps are presented. The authors observe and quantify the immiscible hypermonotectic reaction of AlBi10 in wt alloy and dendrite evolution in AlGe10 in wt casting alloy during fast solidification. The combustion process and the evolution of the constituents are analyzed in a burning sparkler. Finally, the authors follow the structure and density of two metal foams over a long period of time and derive details of bubble formation and bubble ageing including quantitative analyses of bubble parameters with millisecond temporal resolutio

Large-Range Movements of Neotropical Orchid Bees Observed via Radio Telemetry

Neotropical orchid bees (Euglossini) are often cited as classic examples of trapline-foragers with potentially extensive foraging ranges. If long-distance movements are habitual, rare plants in widely scattered locations may benefit from euglossine pollination services. Here we report the first successful use of micro radio telemetry to track the movement of an insect pollinator in a complex and forested environment. Our results indicate that individual male orchid bees (Exaerete frontalis) habitually use large rainforest areas (at least 42–115 ha) on a daily basis. Aerial telemetry located individuals up to 5 km away from their core areas, and bees were often stationary, for variable periods, between flights to successive localities. These data suggest a higher degree of site fidelity than what may be expected in a free living male bee, and has implications for our understanding of biological activity patterns and the evolution of forest pollinators

Correlation between foam structure and mechanical performance of aluminium foam sandwich panels

Aluminium foam sandwich panels containing aluminium alloy sheets AFS have been made available now in sizes up to a few square metres but an unresolved problem in production is how to cope with non uniformities of the foam and the general lack of mechanical property data of AFS. We investigate large industrial AFS panels and test X ray radiography as a method to identify weak points in the foam core. For samples in which defects are identified, correlation with failure in tensile and bending tests is investigated. The properties of a large number of samples tested in compression, tension and bending are determined and presented in AFS property tables. We find that X ray radiography has the potential to identify flawed and potentially weak AFS panels and can be used to test 100 of an industrial production output. The mechanical data measured for in total 120 samples provides a more reliable data base compared to the hitherto published sparse informatio