Ⅰ、引言热导检测器由于其结构可靠、操作简单和几乎无选择的响应,而常常在气相色谱法中采用。新近,由A.B.Richmond做了文献评论[1]。通常,卡他计由构成惠斯登电桥的四个电阻组成。当载气流过一个或二个被桥电流加热的热丝敏感元件时,电桥平衡。当组分和载气的混合物通过热丝时,出现电桥不平衡电压,这不平衡电压就作为检测信号。不平衡信号是由于敏感元件温度的变化而改变其电阻值和通 I. INTRODUCTION Thermal conductivity detectors are often used in gas chromatography due to their robust construction, simple operation and almost no selective response. Recently, A.B.Richmond made a literature review [1]. Often, the kartar consists of four resistors that make up a Wheatstone bridge. The bridge balances when the carrier gas flows through one or two of the heated wire sensing elements heated by the bridge current. When the mixture of component and carrier gas passes through the hot filament, a bridge imbalance voltage appears, which is the detection signal. Unbalanced signal is due to changes in the temperature sensor components and change its resistance value