Word: zero
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Dates: during 1930-1939
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Studies of the vastness of the universe and the invisible smallness of the atom are remote from the things of everyday life. Scientists also go far from familiar things in the study of low temperatures. Hydrogen liquefies at 252.7° below zero Centigrade and helium liquefies at - 268.9°. Compared to such temperatures, the inside of an ice-cream freezer is a seething furnace. The utmost cold, absolute zero (zero on the Kelvin scale), comes out at - 273.13° on the arbitrary Centigrade scale (zero for the freezing point of water, 100 for the boiling point). Scientists have not quite...
...centres of world research in cryogenics are: the University of Leyden in Holland, Oxford University in England, the University of California in the U. S. In California the work is directed by handsome, dapper William Francis Giauque, who first devised the method of cooling magnetic salts closer to absolute zero than had previously been done. His method makes use of the principle that magnetization heats matter, demagnetization chills it. After preliminary cooling with liquid helium, the salt is magnetized, the heat thus generated drawn off into a jacket filled with helium vapor; then demagnetization pushes the substance down one notch...
...researchers work with magnetic fields up to 27,600 gauss (magnetic units), whereas Dr. Giauque must get along with 8,000 gauss until his university finds the money to string bigger power lines into his lab oratory. Another reason is that Giauque does not regard the pursuit of absolute zero as a competitive stunt, but as a means of studying entropy, and for this purpose the region within a degree of the zero is cold enough. Such study is a great chemical timesaver. For all chemical reactions must obey the laws of thermodynamics. In the absolute zero region information...
...Physical Review last week, Dr. Giauque published a report on the viscosity of liquid helium in the absolute zero region. Viscosity is "fluid friction" or degree of stickiness. Even pure water has some viscosity. But about 2° above absolute zero, liquid helium has so little stickiness that - as several cryogenic experimenters have found - "rather phenomenal surface films" will spread over any surface brought in contact with it. These films will, in fact, climb right out of the liquid and ascend to considerable heights against gravity...
...Giauque measured the capillary flow of liquid helium through a channel only one-ten-thousandth of one centimetre wide. He obtained such a low value for the viscosity at one degree above that he concluded there would be no fluid friction whatever at the utter cold of absolute zero...