Feb 19, 2009
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.
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Conventional washing machines cause excessive damage and wrinkling to clothes primarily during the water removal step. With the introduc
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The Dow Chemical Company is the leading producer of polyalkylene glycols (PAGs) used in synthetic fluids and lubricants where petroleum,
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