It’s a matchup worthy of a late-night cable movie: put a school of starving piranha and a 300-pound fish together, and who comes out the winner? The surprising answer—given the notorious guillotine-like bite of the piranha—is Brazil’s massive Arapaima fish. The secret to Arapaima’s success lie in its intricately designed scales, which could provide “bioinspiration” for engineers looking to develop flexible ceramics.
The inspiration for this study came from an expedition in the Amazon basin that Marc Meyers, a professor at the Jacobs School of Engineering at UC San Diego, took years ago. The mechanical and aerospace engineering professor wondered at the Arapaima's armor-like protective scales. How could it live in piranha-infested lakes, where no other animals could survive?
Meyers and colleagues set up a lab experiment that pits piranha against Arapaima by using a machine that resembles an industrial-strength hole punch. Piranha teeth were attached to the top “punch,” which was pressed down into Arapaima scales embedded in a soft rubber surface (which mimics the soft underlying muscle on the fish) on the lower “punch.” The teeth can partially penetrate the scale, but crack before they can puncture the muscle. In the case of Arapaima, the ingeniously designed scales serve as peace through strength, allowing them to coexist with piranha when the two are crowded into Amazon basin lakes during the region’s dry season.
The combination of hard and soft materials, the researchers note, give the scales several ways to repel the bite. The scales overlap like shingles on the fish, and each scale has a “very hefty mineralized layer on top of it. People living in the Amazon sometimes use the ridged Arapaimas scales (which can be nearly four inches in length) as nail files. The corrugated surface keeps the scales’ thick mineralized surface intact while the fish flexes as it swims. Ceramic surfaces of constant thickness are strained when forced to follow a curved surface, but the corrugations allow the scales to be bent more easily without cracking.
The “miracle material” graphene is the world’s thinnest known coating for protecting metals against corrosion. In the study, Dhiraj Prasai and colleagues point out that rusting and other corrosion of metals is a serious global problem, and intense efforts are underway to find new ways to slow or prevent it. Corrosion results from contact of the metal’s surface with air, water or other substances. One major approach involves coating metals with materials that shield the metal surface, but currently used materials have limitations. The scientists decided to evaluate graphene as a new coating. Graphene is a single layer of carbon atoms, many layers of which are in lead pencils and charcoal, and is the thinnest, strongest known material. That’s why it is called the miracle material. In graphene, the carbon atoms are arranged like a chicken-wire fence in a layer so thin that is transparent, and an ounce would cover 28 football fields.
The old saw that a watched pot never boils may not apply to pots given an ultra-thin layer of aluminum oxide, which researchers have reported can double the heat transfer from a hot surface to a liquid.
TI-Automotive va commercialiser des composants en acier cuivré pour les applications antibactériennes dans les environnements HVAC. Il a fait à appel Sirris pour mettre au point la qualité de l'acier cuivré.
ITM Awards 2012 Best Patented Innovation : Vergokan a développé et breveté des chemins de câbles électriques uniques par leur forme trapézoïdale, par leurs possibilités d’empilage et par la simplicité de leur montage par enclipsage.
ITM Awards 2012 Best Patented Innovation: CNH ontwikkelde en patenteerde een systeem dat ervoor zorgt dat aan het eind van een werkopdracht alleen de volledige baal wordt uitgeworpen en het begin van de volgende baal in de kamer wordt gehouden voor de volgende opdracht.
The pitcher plant is an insect-munching vine found lurking in some Asian forests. The plant has modified leaves that grow into bulbous jugs with a slippery mouth, leading to a pool of juices at the base.