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A Study of Equilibrium in Argon Arcs
1Institute for Basic Standards, National Bureau of Standards, Washington, D.C. 20234.
Abstract:
The intensities of the 7147 Å Ar i and 4806 Å Ar ii lines obtained from wall-stabilized arcs at pressures of 0.2 to 5 atm are presented in an Olsen-Richter diagram. Departures from equilibrium are evident at electron densities below 5 × 1016 cm-3. The assumption of equilibrium at higher electron densities leads to transition probabilities in fair agreement with lifetime measurements.
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Noble Gases
The elements in group 18 are noble gases (helium, neon, argon, krypton, xenon, and radon). They earned the name “noble” because they were assumed to be nonreactive since they have filled valence shells. In 1962, Dr. Neil Bartlett at the University of British Columbia proved this assumption to be false.
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