Category Chemistry/Nanotechnology

Computers aid discovery of new, inexpensive material to make LEDs with high color quality

Under UV light, the SLAO phosphor emits either green-yellow or blue light depending on the chemical activator mixed in. Credit: David Baillot/UC San Diego Jacobs School of Engineering

Under UV light, the SLAO phosphor emits either green-yellow or blue light depending on the chemical activator mixed in. Credit: David Baillot/UC San Diego Jacobs School of Engineering

A team led by engineers at the University of California San Diego has used data mining and computational tools to discover a new phosphor material for white LEDs that is inexpensive and easy to make. Researchers built prototype white LED light bulbs using the new phosphor. The prototypes exhibited better color quality than many commercial LEDs currently on the market.

Phosphors, which are substances that emit light, are one of the key ingredients to make white LEDs. They are crystalline powders that absorb energy from blue or near-UV light and emit light in the visible spectrum...

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New Tech for commercial Lithium-ion Batteries finds they can be charged 5X fast

This is a lithium battery temperature sensor. Credit: WMG, University of Warwick

This is a lithium battery temperature sensor. Credit: WMG, University of Warwick

Researchers at WMG at the University of Warwick have developed a new direct, precise test of Lithium-ion batteries’ internal temperatures and their electrodes potentials and found that the batteries can be safely charged up to five times faster than the current recommended charging limits.

The new technology works in-situ during a battery’s normal operation without impeding its performance and it has been tested on standard commercially available batteries...

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Suiker’s Equations prevent 3D-printed Walls from Collapsing or Falling over

These are rectangular shapes printed at the TU Eindhoven 3-D-concrete printer. Suiker elaborated his equations for rectangular layouts like these. Credit: Rob Wolfs/Eindhoven University of Technology

These are rectangular shapes printed at the TU Eindhoven 3-D-concrete printer. Suiker elaborated his equations for rectangular layouts like these. Credit: Rob Wolfs/Eindhoven University of Technology

3D-printed materials commonly are soft and flexible during printing, leaving printed walls susceptible to collapse or falling over. Akke Suiker, professor in Applied Mechanics at Eindhoven University of Technology, had a Eureka moment and saw the solution to this structural problem. He developed a model with which engineers can now easily determine the dimensions and printing speeds for which printed wall structures remain stable. His formulae are so elementary that they can become commonplace in the fast growing field of 3D printing.

Conventional concrete deposited in formwork typically is al...

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Engineers develop Smart Material that Changes Stiffness when Twisted or Bent

Examples of the new smart material, left to right: A flexible strip; a flexible strip that stiffened when twisted; a flexible strip transformed into a hard composite that can hold up a weight. Credit: Christopher Gannon/Iowa State University

Examples of the new smart material, left to right: A flexible strip; a flexible strip that stiffened when twisted; a flexible strip transformed into a hard composite that can hold up a weight. Credit: Christopher Gannon/Iowa State University

Scientists have developed a rubbery material that transforms itself into a hard composite when bent, twisted or squeezed. The new material could be used in medicine to support delicate tissues or in industry to protect valuable sensors. Stress a muscle and it gets stronger. Mechanically stress the rubbery material – say with a twist or a bend – and the material automatically stiffens by up to 300%, the engineers said...

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