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A D V A N C E D M A T E R I A L S & P R O C E S S E S | O C T O B E R 2 0 1 9 7 TREKKY GAME TACKLES GRAPHENE A research team led by Toma Susi at the University of Vienna is using an advanced electron microscope called the UltraSTEM to manipulate strong- ly bound materials with atomic pre- cision. Because the instruments are fully computerized, simulation can show how researchers actually work with them. A simulation game on display at the Vienna Technical Muse- um in a special exhibit called “Work & Production; thinking_forward_” is now available online, together with the latest research on silicon impurity manipulation in single-walled carbon nanotubes. The game, called Atom Tractor Beam, is named after the science fiction concept of an attrac- tive beam of energy popularized by Star Trek. The Nion UltraSTEM allows 50,000,000x magnification. Image con- trast depends on how much the elec- trons are scattered at each location, making it possible to see precisely where impurities are located. In ad- dition to imaging, the microscope’s focused electron beam can be used to move the atoms. The beam scans across a graphene sample line by line, revealing the locations of car- bon atoms that make up the lattice OMG! OUTRAGEOUS MATERIALS GOODNESS as well as the bright- er silicon impurities. Because these are confined one-dimen- sional structures, this advance may enable new kinds of tunable electronic devices. www. univie.ac.at. DRAGONFISH INSPIRE TRANSPARENT CERAMICS Researchers led by the Univer- sity of California, San Diego recent- ly learned why the teeth of deep- sea dragonfish are transparent. This unique feature helps camouflage dragonfish from prey and is a result of their teeth having an unusual- ly crystalline nanostructure mixed with amorphous regions. The enam- el-like layer consists of hydroxyapa- tite nanocrystals structured in a way that prevents light from scattering or reflecting off the surface of the teeth. The dentin layer is also structured in its own particular way: It lacks mi- croscopic channels called dentin tu- bules, which give the teeth of humans and other animals their color. The absence of tubules is also responsible for making dragonfish teeth transpar- ent. The findings could provide bioin- spiration for scientists aiming to de- velop transparent ceramics. ucsd.edu . An electron beam focused on a carbon atom can make it jump to where the beamwas placed. Courtesy of Toma Susi. Only 7% of plastic water bottles are recycled, with the rest ending up in landfills or the ocean. Deep-sea dragonfish with transparent teeth. Courtesy of David Baillot/UCSD. FROM PLASTIC BOTTLES TO PROSTHETIC LIMBS It is estimated that more than 100 million people worldwide have had a limb amputated. Meanwhile, roughly one million plastic water bottles are bought every minute, yet only 7% are recycled—with the rest entering landfills or the ocean. Karthikeyan Kandan, senior lectur- er in mechanical engineering at De Montfort University Leicester (DMU), U.K., recently produced a prosthetic limb socket made of recycled plastic bottles. Kandan found he could grind the bottles down and use the granu- lated material to spin polyester yarns, which can then be heated to form a solid lightweight material that can be molded into prosthetic limbs. The cost of producing a prosthetic socket this way is just $12 compared to the industry average of around $6200. The project was paid for by Global Challenges Research Funding (GCRF), which supports research that addresses challenges faced by devel- oping countries. Kandan now plans to conduct a larger study with peo- ple from different parts of the world so that his design can be adapted to meet individual needs. www.dmu. ac.uk.