sample injector in chromatography, in analytical chemistry

https://dx.doi.org/10.1351/goldbook.S05458
A device by which a liquid or gaseous sample is introduced into the apparatus. The sample can be introduced directly into the carrier-gas stream, or into a chamber temporarily isolated from the system by values which can be changed so as to make an instantaneous switch of the gas stream through the chamber. The latter is a by-pass injector.
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