Word: geigers
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Dates: during 1940-1949
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...M.I.T. have announced that when a sample of rock is bombarded with neutrons (heavy nuclear particles) from the cyclotron, some elements in the ore become radioactive and give off particles which can be detected either 1) on a photographic film in contact with the ore, or 2) with a Geiger counter, an instrument which clicks or marks a tape as each particle shoots through it. Since each element has a unique rate of radioactive decay (e.g., radioactivity of manganese declines by one-half every 2.5 hours, of gold every 2.5 days), the identity and quantity of the hidden elements...
...detection of an element by its radioactivity is up to one million times as sensitive as by chemical analysis. The radioactivity can be detected by killing an animal after it has eaten radioelements, then assaying the radioactivity of its various tissues. It can also be detected by placing a Geiger counter, a device which measures radioactivity, over a part of the body where the tracer elements are suspected so that the metabolic ebb & flow of the tagged substance can thus be observed while the subject is alive. Or the detection can be accomplished by taking paper-thin slices of plant...
...Francisco, where many hospital staff members fell sick. Health Officer Jacob Casson Geiger asked for a $7,500 appropriation to hire substitutes, ordered postponement of all operations except for emergencies...