scientific american - 2001 03 - sculpting the earth from inside out
scientific american - 2001 03 - sculpting the earth from inside out
... material hotter than the surround- ing rock of the earth s mantle pushes to- ward the surface in a concentrated stream. The funnel ends below the earth s outer crust, where the plume material spreads and ... tastes. Contents Sculpting the Earth from Inside Out 32 Michael Gurnis Powerful motions deep inside the planet do not merely shove fragments of the rocky s...
Ngày tải lên: 12/05/2014, 16:08
scientific american - 2001 05 - get the idea (tomorrow's web will)
... of Doñana, in southwest Spain near Seville, Francisco Palomares outlines the glaring difference between the two habitats that run on either side. To the southeast is open pas- tureland; closer to the fences ... poachers drawn to the reserve in search of easy pick- ings. In fact, in some places there are fewer badgers on the inside of the fenced-in park than on adjacent areas o...
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scientific american - 2001 10 - beyond the zone
... produce therapeutic pro- teins. McCormick thinks that the single-chain anti- bodies can be adapted easily to one-size-fits-all thera- pies, perhaps against cancers of the pancreas, colon and other ... human ingenuity as the human sling- shot, the toe puppet, the braille slot ma- chine, the jet-powered surfboard, the pneu- matic shoe-lacing apparatus and a per- sonal enclosure for...
Ngày tải lên: 12/05/2014, 16:10
scientific american - 1993 03 - black holes and the centrifugal force paradox
... together can determine the thick- ness of the ice and the nature of the underlying rock. With Robin E. Bell of the Lamont-Doherty Geological Obser- vatory, the co-leader of ALICE, Blanken- ship ... largest block of problem states is not in the Òrust beltÓ of the North, nor in the high-traÛc re- gions of the Northeast and Southwest, but rather in the southeastern U.S. [se...
Ngày tải lên: 12/05/2014, 14:49
scientific american - 1994 03 - visiting yourself in the past
... sublima- tion) and then analyze everything that comes out. Their results look quite a bit diÝerent from those of their col- leagues. A 35,000-year-old ice sample from the Greenland Ice-Sheet ... the northern section of the Mid-Atlantic Ridge. Along the south- ern wall, mantle peridotites were found to outcrop in the lower part of the slope. Above them were gabbros, rocks crea...
Ngày tải lên: 12/05/2014, 14:54
scientific american - 1997 03 - the rising seas - how much of a threat
... the way from the sun’s in- terior to the earth and out to the farthest reaches of the solar wind. Some of its in- struments are now poised to resolve sev- eral other mysteries. Two of them, the GOLF ... persists through the convection zone. Further- more, the rotation speed becomes uni- form from pole to pole about a third of the way down. Thus, the rotation ve- lo...
Ngày tải lên: 12/05/2014, 15:21
scientific american - 2000 03 - what computers are learning from them
... continued from page 22 ANTI GRAVITY C-A-T-T-T-T-T-T-T-T T he fog comes on little cat feet,” wrote Carl Sandburg. The great poet and historian may merely have been attempting to animate water va- por, ... deviat- ing from established formulas, he talks about the profits his projects have earned and about the desire in a grow- ing number of communities to stop de- velopment altogether....
Ngày tải lên: 12/05/2014, 16:01
scientific american - 2001 06 - the paradox of the sun's hot corona
... grow the same way that planets do: from the agglomeration of smaller units. The layering of the Milky Way bears that out. On the other hand, cold-dark-matter theories have trouble explaining the ... inaccessible from the ground, while ground-based telescopes can gather reams of da- ta unrestricted by the bandwidth of orbit-to -Earth ra- dio links. The findings may be cr...
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scientific american - 2001 12 - india, pakistan and the bomb
... Scientific American, Inc. 36 SCIENTIFIC AMERICAN DECEMBER 2001 BETTMANN/CORBIS Profile of the most-talked-about environmental issues of the 20th century. The year before her 1986 walk in the cold, Sol- omon ... Copyright 2001 Scientific American, Inc.Copyright 2001 Scientific American, Inc. or Life By Rakesh K. Jain and Peter F. Carmeliet Copyright 2001 Scientifi...
Ngày tải lên: 12/05/2014, 16:11
scientific american - 1993 04 - controlling the quantum jitters of atoms
... gigahertz). In the Garching mi- cromaser the atoms all had nearly the same velocity, so they spent the same time inside the cavity. This apparatus is simply another re- alization of the atom-cavity ... carry them well away from the main asteroid belt between Mars and Jupiter along paths that pass close to the orbit of the earth. Their passage by the earth does not...
Ngày tải lên: 12/05/2014, 14:49