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TECHNOLOGYSPOTLIGHT
Advances in technology across industry
Sustainable concrete mixtures for Lab on a chip the 3D printing of breakwater units A
IN
the swiftly evolving area of 3D concrete printing, a new research project has been set up by Ghent University, construction company BESIX, start-up ResourceFull and engineering company Witteveen+Bos. The research will focus on developing sustainable concrete mixtures suitable for the printing of breakwater units. As the major construction cost of a breakwater unit is related to the logistic resources needed to move the breakwater units from the yard to the construction site, the possibility to print it in situ, possibly even below the water level, would be very advantageous. Moreover, 3D printing would make it possible to define a tailor-made model breakwater unit, with
more complex and optimised shapes in line with local wave patterns and sea currents. In addition, the layered surface, produced by 3D printing, would allow for additional energy dissipation. However, printing such massive units is a real challenge as the high binder contents currently used in printable mixtures would cause thermal cracking in addition to the drying shrinkage cracks which are related to this automated production technique. To guarantee the durability of the unit in a marine environment, the research partners want to develop a printable mixture which answers all requirements to print the contour or both the contour and the infill pattern of the breakwater unit. Visit: www.ugent.be
team from KTH Royal Institute of Technology in Stockholm has created a device that precisely dispenses and stores liquids that can be used on a range of diagnostic lab-on-a-chip platforms, at an estimated manufacturing cost of $2 to $6. The technology, which could also be scaled up in size for use in packaging food, cosmetics and chemicals, was reported in Nature Communications. Lab-on-a-chip technology promises to transform expensive health care laboratories into small, affordable and portable chips that can perform various tests automatically at points of care. Simpler examples of LOC, such as home pregnancy tests, have already begun this transition to a degree. Just as all laboratories rely on storage and dispensing devices, LOC too relies on being able to efficiently store and then release different liquids on a chip. The simplified dispenser comprises a tube with an aperture that is covered by an elastic membrane. It’s activated when the internal pressure becomes greater than the force required to stretch the membrane. Pressure can be exerted by pushing with a finger or from the artificial gravity a centrifuge creates. When the internal pressure reaches the critical level, the membrane stretches and provides a path for the liquid to discharge. Visit: www.kth.se
New material to push the boundaries of silicon-based electronics
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he electronics market is growing constantly and so is the demand for increasingly compact and efficient power electronic systems. The predominant electronic components based on silicon will in the foreseeable future no longer be able to meet increasing industrial requirements. This is why scientists from the University of Freiburg, the
Sustainability Center Freiburg and the FraunhoferGesellschaft have joined forces in order to explore a new material structure that may be better suited for future power electronics. The recently launched project ‘Research of Functional Semiconductor Structures for Energy Efficient Power Electronics’ (in short ‘Power Electronics 2020+’) is researching the novel semiconductor material scandium aluminum nitride (ScAlN). ScAlN is a piezoelectric semiconductor material with a high dielectric strength which is largely unexplored worldwide with regard to its usability in microelectronic applications. “The fact that scandium aluminum nitride is especially well suited for power electronic components, due to its physical properties, has already been proven,” explains Dr Ing. Michael Mikulla, project manager on the part of Fraunhofer IAF. The aim of the project is to
grow lattice-matched ScAlN on a GaN layer and to use the resulting heterostructures to process transistors with high current carrying capacity. “Functional semiconductor structures based on materials with a large bandgap, such as scandium aluminum nitride and gallium nitride, allow for transistors with very high voltages and currents. These devices reach a higher power density per chip surface as well as higher switching speeds and higher operating temperatures. This is synonymous with lower switching losses, higher energy efficiency and more compact systems,” adds Prof. Dr Oliver Ambacher, director of Fraunhofer IAF. “By combining both materials, GaN and ScAlN, we want to double the maximal possible output power of our devices while at the same time significantly lowering the energy demand,” says Dr Mikulla. Visit: www.iaf.fraunhofer.de Industry Europe 23
