Xcience Newsletter Feb 2017


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Image Credit: NanoFlowCell

Reinventing the Wheel?

At the recent Geneva International Motor Show, Goodyear launched a new spherical tyre concept, aimed at autonomous vehicles. Named the Urban 360, it is produced by 3D printing, and can adapt to the surface it is travelling on. The ‘bionic skin’ contains sensors and a foam-like core which can expand and contract under the control of AI. The result is to produce a ‘dimpled’ surface for wet conditions, and smooth for dry surfaces.

Cool Film

Researchers at University of Colorado have published a paper in Science describing production of a glass/polymer hybrid metamaterial film. When applied to a building, it is claimed that the film has the combined effect of reflecting solar radiation, as well as allowing thermal radiation from the substrate, resulting in enhanced passive cooling of a building or structure.  

According to Xiaobo Yin, co-director of the research, ‘We feel that this low-cost manufacturing process will be transformative for real-world applications of this radiative cooling technology,’ said published in Science.

Gang Tan, an associate professor in the University of Wyoming's Department of Civil and Architectural Engineering and a co-author of the paper commented: ‘Just 10 to 20 square meters of this material on the rooftop could nicely cool down a single-family house in summer,’

As well as cooling buildings and power plants, the material could also help improve the efficiency and lifetime of solar panels, which can overheat to temperatures that hamper their ability to convert solar rays into electricity. [1]

Human Drone

Sitting in a traffic jam on the M25 (other jams are available), we have all, I am sure, wished we could take off and fly. Well, that idea is nearer reality with the latest human-carrying drone vehicle from China, the eHang 184. Carrying a passenger up to 100kg, it can travel for 30 minutes at up to 100mph on a single battery charge. Already tested in Nevada, it is due to run regular operations in Dubai from July 2017. The ‘pilot’ uses a touchscreen to select a destination and the drone is operated by remote auto-pilot from a command centre [2].

Space News

If the above drone flight isn’t enough of an adrenalin rush for you, Blue Origin, run by Jeff Bezos, are progressing with their rocket to take fare-paying passengers into space. The ‘New Shepherd’ sub-orbital rocket has already been tested and work is now underway on the BE-4 propulsion unit being developed for the ‘New Glenn’ orbital rocket. Using four engines, the rocket will be powerful enough to take passengers into orbit around the earth.  

 Satellites

Meanwhile, the European Space Agency has launched the second Sentinel 2 earth observation satellite on board a Vega rocket. As part of the Copernicus programme to monitor the health of the earth, the satellite will become part of a cluster of Sentinel satellites. Currently, Sentinel 2A has been launched in opposite orbit, and provides an open resource of the earth which will be updated very 5 days [3].

Li-ion Battery Anodes

Bringing down the cost of manufacturing Li-ion batteries is an important target. Researchers at Tohoku University have used recycled waste silicon sawdust to produce lower-cost battery anodes. In silicon wafer production, 50% of Si is discarded as industrial waste in the final cutting process, producing about 90 thousand tons a year worldwide.

The team found that pulverising the Si sawdust into Si nanoflakes (~16 nm in thickness) and then coating in a layer of carbon was suitable for use in high capacity and LI-ion batteries. Results to date indicate that a test half-cell can achieve a constant capacity of 1200 mAh/g over 800 cycles. This capacity is 3.3 times as large as that of conventional graphite (ca. 360 mAh/g) [4]

New Properties of Graphene

A research initiative led by Dr Jason Robinson at the University of Cambridge has coupled graphene with a superconducting material - praseodymium cerium copper oxide (PCCO) and found that the graphene exhibited superconductivity. Superconductivity has been produced by other methods such as intercalation of elements such as calcium, but switching on the ‘intrinsic’ superconductivity which graphene should theoretically exhibit has not been previously achieved[5].

Other research at the Univeristy of Cambridge has developed a graphene-based pyroelectric bolometer that detects infrared (IR) radiation to measure temperature with an ultrahigh level of accuracy. The work, published in Nature Communications, demonstrates the highest reported temperature sensitivity for graphene-based uncooled thermal detectors, capable of resolving temperature changes down to a few tens of µK from a few nano-Watts of IR radiation power [6]. 

Cars Powered by Salt Water?

Flow cell energy storage technology has traditionally been limited to large, static installations. NanoFlowCell have developed a mobile electric drive unit which they have demonstrated in the Quantino sports car (see image). In contrast to conventional batteries, the nanoFlowcell® is provided with energy in the form of liquid electrolytes (bi-ION). The positively and negatively charged electrolyte liquids are stored separately in two tanks and are pumped through a converter cell in separate circuits. A permeable membrane allows ion exchange which generates a current. A novel feature is the low voltage of the system (48V). The used electrolyte is filtered to remove salts and expelled, with liquid refueling similar to a conventional IC engine, and the main emission is water.

More info…

  1. http://www.iom3.org/materials-world-magazine/news/2017/feb/13/glasspolymer-hybrid-cools-sun
  2. http://www.bbc.co.uk/news/technology-38967235
  3. http://www.esa.int/spaceinimages/Missions/Sentinel-2
  4. http://www.nature.com/articles/srep42734
  5. http://www.graphene.cam.ac.uk/news/graphene2019s-sleeping-superconductivity-awakens
  6. http://www.graphene.cam.ac.uk/news/ultrahigh-sensitivity-graphene-infrared-detectors-for-imaging-and-spectroscopy-1
  7. https://www.nanoflowcell.com