Research round-up
Researchers at the University of Bath have created a new material that they say could reduce the noise of aeroplane engines by up to 16 decibels, making the sound of a jet engine taking off no noisier than a hair dryer. The material – a graphene oxide-polyvinyl alcohol aerogel – weighs 2.1 kilograms per cubic metre, making it one of the lightest sound insulators ever manufactured. This low weight, achieved by the aerogel’s meringue-like structure, means it could act as an insulator within aircraft engine nacelles (the complex system that optimises airflows and protects the engine) with almost no increase in overall weight. Michele Meo, a professor of mechanical engineering at Bath, who led the research, said: ‘This is clearly a very exciting material that could be applied in a number of ways – initially in aerospace but potentially in many other fields, such as automotive and marine transport, as well as in building and construction.’
A team of scientists has been taking a closer look at the structure of spiders’ feet, with the aim of creating new nanonstructures with extraordinary adhesive abilities. Focusing on the wandering spider, they found that each foot was made up of close to 2,400 tiny hairs or setae, each 100th of a millimetre thick, which together help the spider scale walls and walk across ceilings. To their surprise, they also discovered that all of the hairs were slightly different to each other and possessed unique adhesive properties. ‘Surprisingly, the adhesion forces largely differed between the individual hairs, for example, one hair adhered best at a low angle with the substrate while the other one performed best close to perpendicular,’ said Clemens Schaber from the University of Kiel, who led the study. Nanostructures based on this complex structure remain very difficult to fabricate, but the future could be bright for spider-inspired stickers. ‘Our findings can further optimise existing models for reversible and residue-free artificial adhesives,’ Schaber said.