Die Methodik der Wasserdampf-Sorptionsmessungen

Abstract

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Precision Determination of Adsorption Layers on Stainless Steel Mass Standards by Mass Comparison and Ellipsometry: Part II: Sorption Phenomena in Vacuum

“…Though much research work has been done in the field of microweighing in vacuum or controlled environments [e.g. [16][17][18][19][20][21][22][23][24], it has not yet been possible to determine directly in vacuum the changes of adsorption layers on massive, carefully polished bodies such as precision mass standards with a sufficiently low uncertainty. At normal pressure, the uncertainties of measurement of the adsorbed mass per surface area are approximately 0,l pg .…”

Screening method based on electric hygrometer for obtaining water sorption isotherms

“…The water activity of the sample is determined as the relative humidity above the sample when equilibrium is established. There is a very close correspondence between the water activity and the relative humidity/100 (Gál, 1967).…”

“…Obtaining water sorption isotherms has long been a rather elaborate method for characterizing a material and its relation to water. This is mainly due to the methods available being either expensive, laborious, time-wasting, or not accurate enough (Gál, 1967). The existing methods are based on the determination of the water content, the water activity, or a combination of both.…”