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Feb 19, 2009 | 1
In addition to being the traditional token of marital intent, the diamond has long provided the—ahem—gold standard for super-hard materials. But physicists at Shanghai Jiao Tong University and at the University of Nevada, Las Vegas, say that two lesser-known materials, wurtzite boron nitride and lonsdaleite, are even harder.
Wurtzite boron nitride, the researchers calculate, resists indentation with 18 percent more fortitude than its glittering counterpart, whereas lonsdaleite, a hexagonal lattice of carbon atoms also known as hexagonal diamond, boasts indentation strength a whopping 58 percent greater than that of diamond. That would be a new record for hardness, the team claims in the study, published this month in the journal Physical Review Letters.
Jan 15, 2009 | 1
Look out, Harry Potter: researchers have advanced the study of cloaking—rendering objects invisible by forcing light waves to act as if the objects weren't there.
In a paper published in this week's Science, a team from Duke University and Southeast University in Nanjing, China, reports a new and improved cloak that can conceal a bump—and anything hidden beneath—on a flat surface. Both the surface and the bump (visible at the far left in the photo) must be reflective, however. The new setup is upgraded to function for a relatively broad spectrum of light, whereas previous models had very narrow operational regimes.
This cloak, like its predecessors from the group of David Smith, an electrical and computer engineering professor at Duke, is built from metamaterials—novel composite structures designed to make light work in unusual ways.
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SteveMirsky @philipyam @dcastelvecchi @akuchment This incident must have taken place at the Sam Houston Institute of Technology
kahoakes Anyone seen/made any super cool science websites recently? Last chance to make it into my @sciencefocus column next month... kahoakes NASA Records an Explosion on the Moon So Bright You Could Have Seen It With Your Bare Eyes http://t.co/J4NwMajI4J
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This is a Reduction-to-Practice Challenge that requires written documentation and&
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The Geoffrey Beene Foundation Alzheimer’s Initiative (GBFAI) is launching the 2013 Geoffrey Beene Global NeuroDiscovery Challenge whose
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