sciencehabit (1205606) writes "The Boston marathon bombers Tamerlan and Dzhokhar Tsarnaev reportedly purchased several pounds of black powder explosive before the bombing. Used in fireworks and bullets, the explosive substance is both deadly and widely available. It's also very hard to detect. Now, researchers have modified one bomb-sniffing device to accurately spot very small amounts of black powder, an advance that could make us safer from future attacks."
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