Word: kelvinator
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...field of research. Superconductivity is the phenomenon in which a conducting material loses its normal resistance to the passage of electricity; since virtually no energy is lost, any electric device becomes far more efficient when built with superconductors. The catch is that superconductivity usually occurs only near 0 K (Kelvin), or -460 degrees F, which means the materials must be cooled by expensive, hard-to-handle liquid helium, thus sharply limiting practical applications...
...last winter, when a burst of research activity rescued superconductors from relative obscurity. The excitement followed a discovery in the spring of 1986 by IBM scientists in Zurich. Their find: a metallic ceramic compound that became a superconductor at a temperature well above the previously achieved record of 23.2 Kelvin, or -418 degrees F. By year's end researchers were developing materials that became superconductors at higher and higher temperatures. At the University of Houston, a team led by Paul C.W. Chu set the currently recognized standard last February, when it produced superconductivity at a balmy 98 K (-283 degrees...
Superconductivity is aptly named. It involves a remarkable transition that occurs in many metals when they are cooled to temperatures within several degrees of absolute zero, or, as scientists prefer to designate it, 0 Kelvin. Absolute zero, equivalent to -460 degrees F or -273 degrees C, represents a total absence of heat; it is the coldest temperature conceivable. As the + metals approach this frigid limit, they suddenly lose all their electrical resistance and become superconductors. This enables them to carry currents without the loss of any energy and in some cases to generate immensely powerful magnetic fields. Scientists have recognized...
DESCRIPTION: Highest known superconducting temperatures for various materials on a scale of absolute zero to over 100 Kelvin for the years 1911 to 1980, with illustration of scientist holding thermometer bounding up steps...
Superconductivity was discovered in 1911, when Dutch Physicist Heike Onnes cooled the element mercury to near absolute zero (0 Kelvin, or -460 degrees F) and discovered that it had lost its resistance to electric current. Since then more than two dozen chemical elements and hundreds of compounds have been found to be superconductors near that temperature extreme. The only practical way to make something that cold is to bathe it in liquid helium, which exists only at temperatures below 4 K. But helium is rare, and expensive to liquefy. Even so, the efficiency of electromagnets wound with superconducting wires...