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Hard rain

点击量:   时间:2019-03-07 10:07:03

DIAMONDS rain onto the cores of Uranus and Neptune, say chemists who simulated conditions under their clouds. Robin Benedetti of the University of California at Berkeley and her colleagues squeezed mixtures of methane, ammonia and water to pressures of between 10 and 50 gigapascals and heated them to between 2000 and 3000 kelvin. The methane formed larger hydrocarbons, amorphous carbon and tiny diamond crystals (Science, vol 286, p 100). Like sand suspended in water, Benedetti says,