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The way we sample much of the world's oceans, to see what's living down there, is pretty basic: Ask fishermen. Or just stick a net down there, and examine what we catch. Neither method is ideal. Because you basically catch the fish and kill them. Phi
Problems with samples A: John? Can you come over here for a second? B: Certainly, Mr. Emory. What can I do for you? A: I need you to take a look at these samples. I think there are a few problems. B: Sure. Let me look over them and Ill bring them bac
Mars Rover to Begin Taking Soil Samples This Week Jessica Berman NASA engineers say the Mars rover will begin taking its first soil samples as soon as it departs the landing platform . Engineers say t
RANDI KAYE, CNN CORRESPONDENT: We take our shoes off, remove our laptops, and toss our bottled water all in the name of safety. But are we any safer today than we were before 9/11? Not exactly, says Bruce Schneier, author and security technologist. B
[00:01.56]Gunpowder [00:03.47]Gunpowder was invented by the Chinese [00:05.73]in the eighth century AD. [00:08.28]Early Chinese scientists discovered [00:10.64]that they could make an explosive substance [00:12.76]by mixing sulphur,charcoal and saltp
萨拉热窝市中心爆炸,无一人伤亡 SARAJEVO, Feb. 10 (Xinhua) -- A huge explosion was heard in central Sarajevo Monday night, and police said there were no injuries. A local police press officer told Xinhua the explosion occurred at the en