Category Physics

Unexpected, Star-Spangled find may lead to Advanced Electronics

This tiny US flag -- just a few nanometers wide and invisible to the naked eye -- is arguably the world's smallest image of Old Glory, according to its creators at the University of Texas at Dallas. In an experiment, the nanoflag pattern emerged unexpectedly as sheets of the "stripe" material -- molybdenum ditelluride -- were heated to about 450 degrees Celsius, at which point its atoms began to rearrange and form new structures -- the 'stars' in this false-color image. Each star consists of six central atoms of molybdenum surrounded by six atoms of tellurium. Stacked on top of one another, the stars form nanowires that might power advanced electronics. The transformation from stripes to stars is reported in the journal Advanced Materials. Credit: University of Texas at Dalla

This tiny US flag — just a few nanometers wide and invisible to the naked eye — is arguably the world’s smallest image of Old Glory, according to its creators at the University of Texas at Dallas. In an experiment, the nanoflag pattern emerged unexpectedly as sheets of the “stripe” material — molybdenum ditelluride — were heated to about 450 degrees Celsius, at which point its atoms began to rearrange and form new structures — the ‘stars’ in this false-color image. Each star consists of six central atoms of molybdenum surrounded by six atoms of tellurium. Stacked on top of one another, the stars form nanowires that might power advanced electronics. The transformation from stripes to stars is reported in the journal Advanced Materials. Credit: University of Texas at Dalla

For several years,...

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Silk Sensor could speed development of new Infrastructure, Aerospace and Consumer Materials

These are examples of the silk used in experiments to detect damage in composites, shown under black light. (Left) Ordinary fibroin of the Bombyx mori silk worm. The observed fluorescence is the result of molecules already present in the protein structure of the fiber. (Middle) Mechanophore-labeled silk fiber fluoresces in response to damage or stress. (Right) Control sample without the mechanophore. Credit: Chelsea Davis and Jeremiah Woodcock/NIST

These are examples of the silk used in experiments to detect damage in composites, shown under black light. (Left) Ordinary fibroin of the Bombyx mori silk worm. The observed fluorescence is the result of molecules already present in the protein structure of the fiber. (Middle) Mechanophore-labeled silk fiber fluoresces in response to damage or stress. (Right) Control sample without the mechanophore. Credit: Chelsea Davis and Jeremiah Woodcock/NIST

Researchers have found a way to use molecules of dye to see inside some of the new composite materials being tested for bridges, cars and sporting goods. What’s needed are new lightweight, energy-saving composites that won’t crack or break even after prolonged exposure to environmental or structural stress...

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Wi-Fi on rays of light: 100 times faster, and never overloaded

Researchers may have a new solution to your slow wifi. Credit: © wladimir1804 / Fotolia

Researchers may have a new solution to your slow wifi.
Credit: © wladimir1804 / Fotolia

Research team gets a speed of 42.8 Gbit/s with a ray of light in an optical wireless network. Researchers at Eindhoven University of Technology have come up with a surprising solution: a wireless network based on harmless infrared rays. The capacity is not only huge (more than 40Gbit/s per ray) but also there is no need to share since every device gets its own ray of light. This was the subject for which TU/e researcher Joanne Oh received her PhD degree with the ‘cum laude’ distinction last week.

The system is simple and, in principle, cheap to set up...

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Transparent Ceramics make Super-Hard Windows

This is a sample of transparent polycrystalline cubic silicon nitride with a diameter of approximately two millimeters, synthesized at DESY. Credit: Norimasa Nishiyama, DESY/Tokyo Tech

This is a sample of transparent polycrystalline cubic silicon nitride with a diameter of approximately two millimeters, synthesized at DESY. Credit: Norimasa Nishiyama, DESY/Tokyo Tech

Scientists synthesize 1st sample of transparent silicon nitride, ie popular industrial ceramic DESY.The result is a super-hard window made of cubic silicon nitride that can potentially be used under extreme conditions like in engines. Cubic silicon nitride (c-Si3N4) forms under high pressure and is the 2nd hardest transparent nanoceramic after diamond but can withstand substantially higher temperatures.

“Silicon nitride is a very popular ceramic in industry,” explains lead author Dr. Norimasa Nishiyama from DESY, now is an associate professor at Tokyo Institute of Technology...

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