Electronic nose of using sensor of acoustic surface wave and partitioning column of gas chromatography jointly, and detection method

A gas chromatographic separation and surface acoustic wave technology, which is applied in the field of electronic noses, can solve the problems of poor sensor measurement signal stability and repeatability, less sensitivity than surface acoustic wave sensors, and limit the practical application of gas-sensitive sensors. The effect of good repeatability and high Q value

Inactive Publication Date: 2011-05-04
ZHEJIANG UNIV
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Both metal oxide sensors and conductive polymer sensors are conductivity-type sensors, which are not as sensitive as surface acoustic wave sensors, and both have poor selectivity. Although electrochemical methods have good selectivity, they are mainly used to detect NO2, SO2, H2S and other electrochemically active gases, while VOCs are generally not oxidized, so they cannot be measured electrochemically
At present, the "broad spectrum" of metal oxide semiconductor sensors, conductive polymer sensors and surface acoustic wave sensors makes it difficult for gas sensors to selectively identify mixed gases. The detection system of gas sensor arrays combined with pattern recognition methods is the electronic nose [H.T. Nagle, S. Schiffman, R. Guitierrez-Osuna, The how and why of electronic noses, IEEE Spectrum, 1998.9, p22-23], in the face of a wide variety of unknown gas mixtures with complex components, there is nothing they can do
In addition, because the above-mentioned gas sensor is limited by the performance of the sensitive film coating material, the stability and repeatability of the sensor measurement signal are poor, and the sensitivity is not high enough, which also limits the practical application of the gas sensor for measuring trace VOCs mixed gases.

Method used

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  • Electronic nose of using sensor of acoustic surface wave and partitioning column of gas chromatography jointly, and detection method
  • Electronic nose of using sensor of acoustic surface wave and partitioning column of gas chromatography jointly, and detection method
  • Electronic nose of using sensor of acoustic surface wave and partitioning column of gas chromatography jointly, and detection method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] Select the mixed gas of benzene, toluene, ethylbenzene and xylene as the mixed gas to be tested, first control and adjust the heating device 6 provided on the periphery of the gas chromatographic separation column 5, and keep the gas chromatographic separation column 5 at 40°C for 2 to 3 minutes, Then the gas chromatographic separation column 5 is heated at a heating rate of 10°C / s until it rises to 150°C, and the flow rate of the carrier gas is 1.5ml / min, so that the mixed gas to be measured is separated from the gas chromatographic separation column 5 successively, and in one analysis Before the discharged gas flows through the micronozzle 7, a positive voltage is applied to the semiconductor refrigeration chip 10 to cool the base of the surface acoustic wave sensor 8 at a temperature of 10°C, so that the hot gas decomposed from the gas chromatography separation column 5 passes through the micronozzle 7 Spray onto the surface of the surface acoustic wave sensor 8 to ca...

Embodiment 2

[0024]With the mixed gas of acetone, ethanol, methyl alcohol, isoprene, acetic acid, propionic acid as the mixed gas to be measured, at first control and adjust the heating device 6 that the gas chromatographic separation column 5 periphery is provided with, make the gas chromatographic separation column 5 in 35 Keep at ℃ for 2 minutes, then heat the gas chromatographic separation column 5 at a heating rate of 8 ℃ / s until it rises to 140 ℃, and the flow rate of the carrier gas is 0.8ml / min, so that the mixed gas to be measured is desorbed successively from the gas chromatographic separation column 5 , before a decomposed gas flows through the micronozzle 7, a forward voltage is applied to the semiconductor refrigeration chip 10 to cool the substrate of the surface acoustic wave sensor 8 at a temperature of 5°C, so that the heat decomposed from the gas chromatography separation column 5 The gas flow is sprayed onto the surface of the surface acoustic wave sensor 8 through the mi...

Embodiment 3

[0026] The mixed gas of butanone, pentane, chloroform, dimethylamine, butanol, amyl alcohol, and trichloroethylene is used as the mixed gas to be measured. The separation column 5 is kept at 38° C. for 2 to 3 minutes, and then the gas chromatographic separation column 5 is heated at a heating rate of 9° C. / s until it rises to 145° C., and the flow rate of the carrier gas is 1.2 ml / min, so that the mixed gas to be measured is transferred from the gas chromatograph The separation column 5 successively resolves, and before a kind of resolved gas flows through the micronozzle 7, a positive voltage is applied to the semiconductor refrigeration chip 10, and the substrate of the surface acoustic wave sensor 8 is refrigerated, and the temperature is 7° C. The hot gas analyzed by the separation column 5 is sprayed onto the surface of the surface acoustic wave sensor 8 through the micro nozzle 7, and condensation and adsorption occur. The frequency detector 9 is used to detect the drift ...

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Abstract

An electronic nose applying both sound surface wave transducer and gas-phase chromatograph separation column is prepared for connecting six-way valve separately to sample feeding-in opening, absorption tube, gas-phase chromatograph separation column, gas-carrying bottle and air pump; connecting said separation column to micro-nozzle; setting sound surface wave transducer under micro-nozzle; arranging said transducer on semiconductor refrigeration plate and connecting said transducer to frequency detector. Its detecting method is also disclosed.

Description

technical field [0001] The invention relates to an electronic nose, in particular to an electronic nose combined with a surface acoustic wave sensor and a gas chromatography separation column and a detection method. Background technique [0002] With the development of the economy, people's living standards are getting higher and higher, but the air pollution problems caused by the subsequent industries and high-tech industries are becoming more and more serious, such as petrochemical industry emissions, toxic gases in room decoration, semiconductor industry and spraying, Pollution gases produced by packaging and tanning and footwear industries, etc., these toxic and harmful gases have exacerbated the deterioration of air quality. Air pollution has become one of the important sources of exposure for people in today's society, which seriously threatens human health. [0003] Therefore, it is necessary to develop toxic and harmful pollution gas detection technology and instru...

Claims

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Application Information

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Patent Type & Authority Patents(China)
IPC IPC(8): G01N33/00
Inventor 郭希山王立人
Owner ZHEJIANG UNIV
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