Word: carbons
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Dates: during 1940-1949
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...almost invisible speck of radioactive carbon-a millicurie*- became the first byproduct of atom-bomb-making to be released for medical research. Last week's buyer (at $367 plus handling charges and deposit on the bottle): the Barnard Skin and Cancer Hospital of St. Louis, which will use it only in research. It will not cure cancer...
Radioactive carbon is not new; "C-14" has been made in cyclotrons for seven years but in even more minute quantities and at far greater cost. Other elements can also be made radioactive, but C14 is the most useful for cancer research because 1) it remains radioactive for thousands of years, can be recovered and used again, 2) carbon is the key element in all body chemistry. Barnard's researchers will use it as a tracer (it signals its presence by shooting off radiation) to study the metabolism of cancerous cells which must be understood before the disease...
...typical pile is a 20-foot block of graphite (pure carbon) interlarded with lumps of fissionable uranium. The chain begins with the capture of a neutron by a uranium atom. When the atom "fishes" (splits by fission), neutrons released by the reaction fly off at more than 6,000 miles a second. To give the neutrons a maximum chance of being captured by other uranium atoms, they are slowed to "thermal" speed-roughly 3 m.p.s. Normally a neutron slows down to that speed after about 110 collisions with carbon atoms...
Most crying need for them is in medicine, not to cure disease (though the isotopes may do this too), but to probe basic biological processes. Radioactive carbon 14, for example, may be fed to human beings or laboratory animals. Though present only in sub-microscopic quantities, it will announce its presence to sensitive instruments. Physiologists can follow it through the body, even into individual cells...
...exercising options, only the capital gains tax on resale.) The ruling was based on a Supreme Court decision handed down, effective Feb. 25, 1945, on that date. Up till then, stock option plans had been a popular way of getting around heavy taxes. Said Union Carbide & Carbon's Board Chairman Benjamin O'Shea, after catching up with the times: "The Treasury statement has given us cause to pause. We'll have to figure out a more efficient plan...