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Igure, Requency, Hange vs – INFICON RQCM - Quartz Crystal Microbalance Research System User Manual

Page 59: Lycerol, Figure 14 an

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RQCM – RESEARCH QUARTZ CRYSTAL MICROBALANCE

THEORY OF OPERATION

5-7

illustrated by Figure 14 and Figure 15, respectively. Note that some of the discrepancy in the

resistance curve could arise from an error in estimating the active electrode area.
The RQCM utilizes the PLO technology which allows the sensor crystal to operate under heavy

viscous loading. INFICON Crystal Holders support operation in gas and liquid environments and

provide single-electrode exposure to liquids as required for compatibility with electrochemical

QCM measurements. The RQCM will maintain oscillation up to a series resonance resistance of

about 5 kΩ. It will support crystal operation in highly viscous solutions up to 88% weight

percentage of glycerol

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. The RQCM computer software provides a friendly interface for setting

up the RQCM to log and graph data collected from the sensor crystal such as frequency change,

resistance change, mass, etc.

Frequency Change vs. Wt % Glycerol

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Wt % Glycerol

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a Frequency (

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Theory
RQCM

Figure 14 Frequency Change vs. Wt % Glycerol