Design And Research Of Condensed Surface Acoustic Wave Explosive Sensor

In recent years,terrorists have become increasingly rampant,and international and domestic terrorist attacks have occurred frequently,causing a large number of innocent victims and major economic losses.The main way terrorists conduct terrorist attacks is through bomb attacks through explosives.Usually,terrorists will choose to carry out terrorist attacks in densely populated areas.Because of the high power of the bombs,they will cause mass casualties.Therefore,it is urgent to improve the sensitivity of various explosives detection technologies,respond quickly to explosives in response to different occasions,prevent precautions against explosive terrorist attacks,and effectively avoid casualties and property losses caused by terrorist attacks.The paper mainly includes the following contents:1.The surface acoustic wave sensor is used as the research object of this subject through the investigation of explosives detection technology.This subject mainly studies two kinds of surface acoustic wave gas sensors using surface acoustic wave devices as detectors.Based on the principle of surface acoustic wave gas sensor,the working principle of traditional coated surface acoustic wave gas sensor and condensing SAW gas sensor are analyzed,and the advantages and disadvantages of the two are compared.2.The principle of the condensing SAW explosives sensor was analyzed,and the main modules of the sensor were analyzed and designed.Among them,the enrichment device uses a traditional tube-type enrichment device and uses Carboxen-1000 as an enrichment material.After testing,the sensor response value can reach 6.5 kHz after enriching the 27 ppb 2,4-DNT for 1 min.The air chamber is equipped with a closed air chamber with a height of 9 mm and the air chamber structure is simulated.The simulation results show that the air chamber meets the design requirements.Finally,the above modules are integrated to form a complete explosives detection system,which lays the foundation for subsequent testing and analysis.3.The gas-sensitive characteristics of 2,4-DNT were tested by the condensed SAW explosives sensor test system.The repeatability of the sensor was good,and the test results of different condensation temperatures were fitted to visually show the sensor condensation.The relationship between temperature and response value,finally through the above test analysis,the condensing SAW sensor has the advantages of rapid response,small baseline fluctuation,large response value and good repeatability.4?In this paper,for the traditional coated surface acoustic wave sensor,two sensitive materials,PLF and DKAP,were selected according to the linear solvent equation.The above two materials were synthesized by chemical synthesis method,and the functional group structure of the sensitive material and the sensitive mechanism to 2,4-DNT were analyzed by infrared spectroscopy.The sensitive material is formed on the surface acoustic wave device by a gas spray coating method.The response characteristics and repeatability of 2,4-DNT sensors with two sensitive membranes were tested.Finally,a comprehensive analysis of the condensing SAW sensor is a good method for explosive detection compared to the traditional coated surface acoustic wave sensor.