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Headspace sampling is a type of sample introduction technique for gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). For headspace techniques, the gas layer, or the headspace above the sample in a vial, is analyzed as opposed to withdrawing a volume from within the sample layer (Figure 1).
Headspaces discussions at Cetie. It is a fact of life that, with a few exceptions, substances expand when the temperature rises. Moreover, as a general rule, liquids expand much more than solids for the same rise in the temperature.
Ullage or headspace is the unfilled space in a container, particularly with a liquid. [1] Etymology. The word ullage comes from the Latin word oculus, used by the Romans to refer to a barrel cork hole. This word was, in turn, taken in medieval French as oeil, from which a verb ouiller was created, meaning to fill a barrel to full capacity.
Headspace vial caps are available in a variety of materials including aluminum, bimetal, and steel; headspace vial cap septa are available in PTFE/silicone, molded PTFE/butyl, and high-temperature varieties. Our headspace vial caps come in either 11 mm, 18 mm, 20 mm or 22 mm sizes.
At filling, oxygen concentration in bottle headspace can range from 1.5 to 2.5 mg/L. 1 The oxygen concentration depends on three factors: wine volume, headspace volume and oxygen concentration in the headspace.
Headspace Calculator for Bottling Operations. Most bottle manufacturers will provide a drawing showing suggested fill heights. In addition to this information, it is important to consider wine temperature at bottling. The Calculator for Bottling Operation provides recommendations for ullage volume, internal bottle pressure, and fill height ...
Headspace gas chromatography uses headspace gas—from the top or "head" of a sealed container containing a liquid or solid brought to equilibrium [1] —injected directly onto a gas chromatographic column for separation and analysis. In this process, only the most volatile (most readily existing as a vapor) substances make it to the column. [2] .
