Methods of humidity determination Part II: Determination of material humidity

Abstract

Part II covers the most common methods of measuring the humidity of solid material. State of water near solid surfaces, gravimetric measurement of material humidity, measurement of water sorption isotherms, chemical methods for determination of water content, measurement of material humidity via the gas phase, standardisation, cosmonautical observations are reviewed.

Early History of Adsorption Measurements

“…The peculiar characteristic of the water molecule facilitates its identification and allows for the application of very different methods to determine humidity. Many of these methods originating from the 19th/20th century are standardized in industrial states (Rübner et al 2008).…”

“…However, weighing in liquids was not successful until quartz resonators became available (Mecea et al 1996). In 1957, Sauerbrey invented the oscillating quartz crystal balance (Sauerbrey 1957(Sauerbrey , 1959.…”

Low Humidity Characteristics of Polymer-Based Capacitive Humidity Sensors

“…gases [8]), detection of a trace moisture content in natural gas pipelines, drying of solid materials, in meteorology [9] at high altitudes (climate change studies), or in cosmonautical observations [10,11], the measurement of low humidity is essential. Some companies meet that need with sensors dedicated to low humidity (e.g.…”