Device and method for measuring liquid density and viscosity on basis of quartz crystal microbalance

Abstract

The invention discloses a device and method for measuring liquid density and viscosity on the basis of a quartz crystal microbalance. The device comprises a sine driving unit, a QCM (Quartz Crystal Monitor) sensing unit, a synchronous detection unit, an analog-digital converter, a digital signal processor and a computer, wherein the sine driving unit is used for generating a sine frequency scanning signal; the QCM sensing unit is driven by the sine frequency scanning signal and used for sensing and testing a liquid; the density and the viscosity of the liquid are converted into alternative-current voltage signals; the synchronous detection unit is used for converting alternative-current voltage signals output from the QCM sensing unit into direct-current voltage signals corresponding to conductive variation of a QCM; the analog-digital converter is used for performing analog-digital conversion on the direct-current voltage signals; the digital signal processor is used for extracting anelectric conductivity peak of a digital signal and a serial connection resonant frequency of the peak; the computer is used for calculating the output of the digital signal processor to obtain the density and the viscosity of the liquid. The device disclosed by the invention is small in size, high in integration degree, simple in measurement process and accurate in measurement result.

Description

technical field [0001] The invention relates to the field of sensor detection, in particular to a measuring device and method for liquid density and viscosity based on a quartz crystal microbalance. Background technique [0002] Density and viscosity are the two most basic physical properties of liquids, which are of great significance in the fields of analytical chemistry, biomedicine, and environmental engineering. Quartz crystal microbalance (QCM) can be used to measure the physical properties of liquids, such as the density and viscosity of liquids, and it can convert the physical properties of the liquid to be measured into measurable frequency signals or conductance signals. [0003] At present, analytical instruments based on QCM sensors are widely used in the fields of biomolecular interaction, polymer material adsorption, germ detection, electrochemical precipitation analysis, and air hygiene quality detection, but there are still few applications in the field of li...

AI Technical Summary

Problems solved by technology

Due to the approximate equivalent of the frequency contributions of two QCM sensors with different structures, the measurement error is relatively large, and the test process is also relatively complicated

In 2011, Itoh et al. proposed a method to measure the density and viscosity of liquids using a single QCM sensor combined with admittance analysis. However, a lot of data needs to be measured, and the data analysis process is very difficult. At the same time, the volume of the network analyzer used in the measurement process Huge, expensive, not conducive to the application in actual production

Images