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By carefully analyzing the vibrational spectra of water with different proportions of hydrogen and deuterium, the scientists ...
WE have recently been investigating the far ultra-violet absorption spectra of a number of organic compounds of the type R 1 COOR 2; R being an alkyl group or a hydrogen atom. It has been found ...
Studying the line spectra produced by hot gases and absorbed by cooler gases allows us to identify the elements in stars. When a gas is very hot, it doesn’t emit all wavelengths of light.