In this paper, frequency dielectric spectroscopy (FDS) and an innovative optical sensor for the detection of 2-furaldehyde (2-FAL) are used to check the degree of ageing of differently processed oil-paper specimens when exposed to thermal stress. The analysis of the trend of moisture content and of 2-FAL concentrations confirms the influence of drying pre-treatment of the specimens on their ageing conditions. FDS elucidated the nature of the drying process of the specimens and the optical sensor correctly assesses a lower 2-FAL production for the vapour phase dried specimens during thermal exposure.

中文翻译：

---

频率介电光谱和用于评估油纸降解的创新光学传感器

在本文中，频率介电光谱 (FDS) 和用于检测 2-呋喃醛 (2-FAL) 的创新光学传感器用于检查不同加工油纸样品在暴露于热应力时的老化程度。水分含量和 2-FAL 浓度趋势的分析证​​实了样品的干燥预处理对其老化条件的影响。FDS 阐明了样品干燥过程的性质，光学传感器正确评估了热暴露期间气相干燥样品的较低 2-FAL 产量。