Word: liquidation
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From the time that Dutch Physicist Heike Kamerlingh Onnes discovered superconductivity in 1911 until the recent rash of breakthroughs, there was only one way to produce the phenomenon: by bathing the appropriate metals -- and later, certain metallic alloys -- in liquid helium. This exotic substance is produced by lowering the temperature of rare and costly helium gas to 4.2 K (-452 degrees F), at which point it liquefies. But the process is expensive and requires considerable energy. Furthermore, unless the liquid helium is tightly sealed in a heavily insulated container, it quickly warms and vaporizes away. Thus the practical...
...past year and a half physicists have stumbled on an unusual class of ceramic compounds that change everything. They too must be cooled to become superconductors, but only to a temperature of 98 K (-283 degrees F). And that suddenly brings superconductivity into the range of the practical; liquid helium can be replaced as a coolant by liquid nitrogen, which makes the transition from a gas at the easily produced temperature of 77 K (-320 degrees F). Moreover, liquid nitrogen is cheaper by the quart than milk and so long- lasting that scientists carry it around in ordinary thermos bottles...
...much promise that Chu filed a patent application on Jan. 12. That promise was soon fulfilled. At the end of the month, after subjecting their creation to a series of heat and chemical treatments, Wu and his assistants began chilling a bit of the compound, by dousing it with liquid nitrogen, and sending an electric current through it. To their amazement, the sample's resistance began to drop sharply at a towering 93 K. Recalls Wu: "We < were so excited and so nervous that our hands were shaking. At first we were suspicious that it was an error...
...return to their previous attitudes, they emit radiation that produces detailed images of the body's soft tissues. MRI machines in use today are enormous (6 ft. by 8 ft. by 10 ft.), largely because of the more than $100,000 worth of bulky insulation required to preserve the liquid helium coolant, which costs an additional $30,000 annually. The improved economics of the new superconductors, says Walter Robb, of General Electric's Research and Development Center, should eventually enable medical institutions to install many more MRI machines, which are invaluable for diagnosing disorders like brain tumors...
Giant particle accelerators are one target for possible upgrading. Currently the most powerful such devices use conventional superconducting electromagnets. If high-temperature superconducting magnets can be developed, millions of dollars could annually be saved in electrical and liquid-helium bills...