Category Physics

This schematic illustrates the novel nanosheet with three parallel segments created by the researchers, each supporting laser action in one of three elementary colors. The device is capable of lasing in any visible color, completely tunable from red, green to blue, or any color in between. When the total field is collected, a white color emerges. Credit: ASU/Nature Nanotechnology

More luminous, energy efficient than LEDs, white lasers look to be the future in lighting and Li-Fi, light-based wireless communication. Arizona State Uni researchers proved semiconductor lasers can emit over the full visible color spectrum: necessary to produce a white laser.

They created a novel nanosheet – thin layer of semiconductor ~1/5 of the thickness of human hair in size -with 3 parallel segments, eac...

This image, at left, shows a previously unknown type of metal deformation — sinuous flow — in which metal is deformed into folds while it is being cut. New research findings, in graph at right, reveal the cutting force can be reduced 50 percent simply by painting metal with a standard marking ink, suggesting that not only can energy consumption be reduced by 50 percent but also that machining metals can be achieved faster and more efficiently, and with improved surface quality. Credit: Purdue University image/ Ho Yeung and Koushik Viswanathan

Previously unknown type of metal deformation – sinuous flow – and a method to suppress could lead to more efficient machining and other manufacturing advances by reducing the force and energy required to process metals.

Purdue team discovered the ph...

Hierarchical structure of wood fibers and the characteristic of cellulose fibrils. Note the rich interchain hydrogen bonds among neighboring cellulose molecular chains.

Paper made of cellulose fibers is tougher and stronger the smaller the fibers get. For a long time, engineers have sought a material that is both strong (resistant to non-recoverable deformation) and tough (tolerant of damage). “Strength and toughness are often exclusive to each other,” said Teng Li, associate professor of mechanical engineering at UMD. “For example, a stronger material tends to be brittle, like cast iron or diamond.”

The UMD team pursued the development of a strong and tough material by exploring the mechanical properties of cellulose, the most abundant renewable bio-resource on Earth...

It contained blasts in a series of controlled explosions in the luggage hold of a Boeing 747 and an Airbus 321. The Fly-Bag, which lines an aircraft’s luggage hold with multiple layers of novel fabrics and composites, was tested under increasing explosive charges on disused planes at Cotswolds Airport, near Cirencester, this week. After the tests, explosives were placed in the aircraft without the lining to show the damage that could be caused.

>>Disasters such as the Lockerbie bombing in 1988 drove the need for this kind of invention, as well as the incident in which a printer cartridge bomb was found on-board a cargo plane at East Midlands Airport in 2010.
Fundamental to the design of the bag is a combination of fabrics which have high strength and impact and heat resistance...