helium
has definitions from the field of chemistry
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[ noun ] (chemistry) a very light colorless element that is one of the six inert gasses; the most difficult gas to liquefy; occurs in economically extractable amounts in certain natural gases (as those found in Texas and Kansas)
Synonyms Used in print (1961 Research Highlights of the National Bureau of...)The efforts and accomplishments fall_into three main categories : absolute thermometry based upon the velocity of sound in helium gas , secondary thermometry involving principally studies of the behavior of germanium resistors , and helium 4 vapor-pressure measurements ( see p. 144 ) . The efforts and accomplishments fall_into three main categories : absolute thermometry based upon the velocity of sound in helium gas , secondary thermometry involving principally studies of the behavior of germanium resistors , and helium 4 vapor-pressure measurements ( see p. 144 ) . An acoustical interferometer has been constructed and used , with helium gas as the thermometric fluid , to measure temperatures near 4.2 and 2.1 * * f . When values of temperature derived with this instrument were compared with the accepted values associated with liquid helium 4 vapor_pressures , differences of about 10 and 7 millidegrees respectively were found . Carbon resistors and impurity doped germanium resistors have been investigated for use as precision secondary thermometers in the liquid helium temperature region . Related terms |
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