Word: nitric
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Dates: during 1960-1969
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...overtakes Cambridge this time of year will be attributed once again to a subtle combination of Spring and hour exams. But the real reason for that feeling of being "unaccountably pooped," says Dr. John T. Middleton, a leading expert on air pollution, is a common air pollutant known as nitric oxide...
Reacting with sunlight and other common air contaminants, nitric oxide forms ozone, a chemical which closes part of the lungs and forces an animal to use more energy to get enough oxygen. Middleton showed other experts at a two-day conference at the New York University School of Medicine last week how ozone "in the quantities you commonly find in New York city air" slows down rats and mice when they exercise on a treadmill...
...crucial time of the final semester approaches, the administration should take effective measures to eliminate this pernicious deterrent to serious study. Harvard scarcely deserves to criticize the Commonwealth if it cannot maintain the purity of its own air. The movement to eradicate Nitric Oxide must begin at home...
...Agena's problems began 368 seconds after launch. At that moment, precisely on schedule, fuming nitric acid fuel began spraying into the rocket's thrust chamber, followed a few milliseconds later by the oxidizer, unsymmetrical dimethylhydrazine. Somehow, too much fuel entered the chamber ahead of the oxidizer. The result was a "hard start" of the Agena's engine, similar to the backfire that occurs when gasoline and air ignite prematurely in an automobile engine...
...eight Discoverer satellites into polar orbits. The Agena is designed to ignite when high in the vacuum of space. This is not easy because few fuels will ignite in a vacuum. Bell gets around the problem by using hypergolic fuels (unsymmetrical dime-thylhydrazine and inhibited red fuming nitric acid) that ignite spontaneously as soon as they come in contact. After the first stage burns out, a small charge of solid propellant flares up and generates gas that runs a turbine and pumps the liquid fuels into the Agena's combustion chamber. They start burning immediately, giving...