为了进一步提高激光诱导击穿光谱(LIBS)技术快速测量粉煤灰未燃碳的性能,分别将Na2SiO3和KNO3作为粉煤灰未燃碳测量的粘合剂,以改善所测粉煤灰样品的可压性。对比分析两种粘合剂条件下未燃碳定标曲线的拟合度、灵敏度、定量分析精确度和检测限,以及Si251.61nm和Si288.16nm分别作为C247.86nm的内标线对未燃碳测量的影响。研究结果表明,利用Na2SiO3作为粉煤灰的粘合剂时,未燃碳的定标曲线拟合度、灵敏度、定量分析精确度和检测限均优于KNO3作为粘合剂时的情况。而以Si251.61nm作为C247.86nm的内标线时,未燃碳测量的灵敏度更高。
In order to further improve the performance of quick measurement of unburned carbon in fly ash by laser- induced breakdown spectroscopy (LIBS), Na2SiO3 and KNO3 are employed as binders to improve the compressibility of the fly ash powder. The fitting coefficient of calibration curve, sensitivity, measuremental accuracy, precision and limit of detection are compared between the two binders, and the performances of Si 251.61 nm and Si 288.16 nm used as the internal standards for C 247.86 nm individually are also investigated. The experimental results show that the fitting coefficient of calibration curve, measuremental accuracy, precision and limit of detection of fly ash mixed with Na2Si03 are better than that of fly ash mixed with KN03, and Si 251. 61 nm as the internal standard for C 247.86 nm can improve the measuremental sensitivitv of unburned carbon in fly ash.