【摘要】 研究了一种快速检测和识别农药敌百虫、乙酰甲胺磷和乐果气体的新方法 ,即动态检测方法。这种方法利用单个SnO2 气体传感器而非阵列在方波温度调制的状态下可实现 3种农药气体的快速检测。实验结果表明 :在 0 .0 2Hz的调制频率和 2 5 0～ 3 0 0℃的温度调制范围 ,传感器表现出高的选择性和稳定性 ;利用FFT频谱和极坐标构建完成对敌百虫、乙酰甲胺磷和乐果的定性和定量检测。更多还原

【Abstract】 A new rapid detecting method (called dynamic measurements) was reported to detect and distinguish organophosphorus pesticide residues such as acephate, trichlorphon and dimethoate in the ambient atmosphere . The method employed only a single SnO 2-based gas sensor in a rectangular temperature mode to perform the qualitative analysis of pure pesticide gas and a binary gas mixture (acephate and trichlorphon) in air. Experimental results showed that high selectivity of the sensor achieved in the range of 250～300℃ and modulating frequency of 0.02 Hz, The quantitative analysis between the pure pesticide gas and mixture was performed by fast Fourier transform (FFT). The higher harmonics of the FFT characterized the nonlinear properties of the response at the sensor surface. The amplitudes of the higher harmonics exhibited characteristic changes which depended on the concentration and the kinetics of gas species on the sensor surface.更多还原