Word: coolant
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...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. Also, the & ceramics may be able...
...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...
...Percy's answer threatens, for a time, to stop The Thanatos Syndrome dead in its tracks. Tom, aided by his young, distant and potentially kissing cousin Lucy Lipscomb, herself a doctor and an epidemiologist, discovers that the local water supply is being laced with heavy sodium from the coolant of a nearby nuclear power plant. Whodunit? Not, it turns out, the National Institutes of Health or the Nuclear Regulatory Commission. The villains are a couple of doctors, both known to Tom, who have contrived on their own to salvage the "American social fabric" by doping the local populace...
...long as a coolant (water in most reactors) keeps flowing around the reactor core, it carries heat away, and the temperature stays under control. If the coolant is lost, the core begins to overheat, like a car with a broken radiator. The chain reaction promptly ceases because rising temperatures cause the fuel to expand, which increases the distances between individual atoms and makes it less likely that the neutrons emitted by one will hit the nucleus of another. But the spontaneous radioactive decay of nuclei goes on. The uncooled reactor core could eventually get hot enough to melt through...
...EXAMPLE of this negligence, according to the former project manager of the NRC, Robert Pollard, is the plan for new vents in reactor cooling systems. If a reactor overheats, hydrogen bubbles or steam form in the cooling system and prevent the coolant from flowing to the core. This happened...