Photo-Pyroelectric Spectrometry and its Application to Flow Analysis

研究了以He-Ne激光器为激发源、PZT热释电陶瓷片为探头的光热释电光谱分析方法。用经典的热传导理论可以解释阶跃函数模式或调制模式的激光辐照所产生的信号。在纳皮尔吸收系数中，检测限确定为1.6 x 10^<-4>cm^-。在杂多蓝法和靛酚法的基础上，将PPES用于天然水中磷酸盐和氨的分批比色测定。检出限为2.7ppb（PO_4^+-P）和2.1ppb（NH_4^+-N）。此外，通过使用PPES测试流动分析。检测限为0.97 × 10 ~（-1）<-4>cm ~<-1>（-1），略优于分批法。这表明PPES可用于流量分析中的检测器。采用流动注射分析技术，对磷酸盐和硅酸盐进行了分析。为了实际使用PPES，期望使用具有高功率的激光二极管以及改进流动池和PZT传感器探针。

Photo-pyroelectric spectrometry (PPES) with a compact sensor probe including a PZT pyroelectric ceramic piece and a He-Ne laser as an excitation source was studied. The signal induced by the laser irradiation in a mode of step function or in a modulated mode could be explained by a classic theory on heat conduction. The detection limit was determined as 1.6 x 10^<-4> cm^- in the Napierian absorption coefficient. The PPES was applied to batchwise colorimetric determination of phosphate and ammonia in natural water on the basis of the heteropoly blue method and the indophenol method, respectively. The detection limit was 2.7 ppb for PO_4^+-P and 2.1 ppb for NH_4^+-N. Further, flow analysis was tested by using the PPES. The detection limit was 0.97 x 10^<-4> cm^<-1>, which was slightly better than that of the batchwise method. This shows that the PPES is available for a detector in the flow analysis. The flow injection analysis for phosphate and silicate was performed by using the PPES. In order to use the PPES practically, the use of a laser diode with high power and improvement of the flow cell and the PZT sensor probe are desired.