Shah Adil, Laurent Olivier, Broquet Grégoire, Kumar Pramod, Ciais Philippe
Laboratoire des Sciences du Climat et de l'Environnement (CEA-CNRS-UVSQ), Institut Pierre-Simon Laplace, Université Paris-Saclay, Site de l'Orme des Merisiers, Gif-sur-Yvette 91191, France.
ACS Omega. 2024 Nov 25;9(49):48323-48335. doi: 10.1021/acsomega.4c06397. eCollection 2024 Dec 10.
The resistance of the Figaro Taguchi Gas Sensor (TGS) decreases when exposed to reducing gas enhancements. TGS gas response can be characterized by comparing measured resistance to a reference resistance, representative of sampling in identical environmental conditions but with no reducing gas enhancement. Thus, this resistance ratio (RR) allows for characterization of reducing gas response, independent of other environmental effects. This work presents controlled laboratory experiments, measurements, and modeling for an analysis on the effect of reducing gas cross-sensitivities on RR. The methane mole fraction ([CH]) was raised to approximately 9 ppm from a 0.492 ppm reference level, and carbon monoxide mole fraction ([CO]) was raised to approximately 4 ppm from a 0 ppm reference level, through multiple simultaneous steps. The independent effect of each gas on RR was directly multiplied, resulting in an inferior RR compared with measurements, implying an interdependence effect. For example, for one TGS unit, when deriving [CH] from RR, a 6 ppm [CH] measurement would be underestimated by 6% at 1 ppm [CO], but only by 1.6% at 0.1 ppm [CO]. A key implication of residual interdependence effects is that any gas characterization must be conducted with the same reference levels of each other reducing gas expected during field deployment, even if measuring a single gas. A first-order interdependence correction is proposed to account for such interdependence effects. Yet, each TGS behaves differently, and interdependence testing takes time. Therefore, the TGS best serves to detect single reducing gases, assuming all other reducing gases to remain constant at their reference levels.
费加罗田口气体传感器（TGS）在暴露于还原性气体增强时电阻会降低。TGS气体响应可以通过将测量电阻与参考电阻进行比较来表征，该参考电阻代表在相同环境条件下但无还原性气体增强时的采样情况。因此，这种电阻比（RR）能够表征还原性气体响应，而不受其他环境影响。本文介绍了用于分析还原性气体交叉敏感性对RR影响的受控实验室实验、测量和建模。通过多个同步步骤，将甲烷摩尔分数（[CH]）从0.492 ppm的参考水平提高到约9 ppm，将一氧化碳摩尔分数（[CO]）从0 ppm的参考水平提高到约4 ppm。每种气体对RR的独立影响直接相乘，导致与测量结果相比RR较低，这意味着存在相互依赖效应。例如，对于一个TGS单元，当从RR推导[CH]时，在1 ppm [CO]时，6 ppm [CH]的测量值会被低估6%，但在0.1 ppm [CO]时仅被低估1.6%。残余相互依赖效应的一个关键影响是，即使测量单一气体，任何气体表征都必须在现场部署期间预期的其他还原性气体的相同参考水平下进行。本文提出了一种一阶相互依赖校正来考虑这种相互依赖效应。然而，每个TGS的行为都不同，并且相互依赖测试需要时间。因此，假设所有其他还原性气体在其参考水平保持不变，TGS最适合用于检测单一还原性气体。
