三基发射药干燥过程总挥含量的快速检测方法

Rapid Detection Method for the Total Volatile Content in Drying Process of Triple-based Gun Propellant

采用近红外光谱法快速测定了三基发射药干燥过程的总挥(醇酮溶剂)含量;通过对比三基发射药药粒样品及总挥的光谱图特点,确定了总挥最佳建模光谱范围;对三基发射药样品的光谱图进行预处理,对比了不同光谱预处理方法的效果,最终确定了最佳光谱预处理方法;采用偏最小二乘法建立了三基发射药样品总挥的校正模型,最终选择总挥建模的最佳主因子数为8,并对模型的预测能力进行了验证。结果表明,确定的最优建模光谱区间为5700~6100cm-1,最佳光谱预处理方法为一阶导数+SNV的组合,总挥含量模型的校正决定系数(RC2)为0.9703,校正均方根误差(RMSEC)为0.1497;预测决定系数(RP2)为0.9628,预测均方根误差(RMSEP)为0.1879;验证集标准偏差与预测标准偏差的比值(RPD)为6.7;将该模型应用到三基发射药干燥过程总挥含量的检测,预测平均偏差为0.025%,建立的总挥模型具有较好的预测性和重复性,在60s内可实现三基发射药干燥过程总挥含量的准确检测。

The total volatile(alcohol and ketone) content of triple-based gun propellant during drying process was quickly determined by near-infrared spectroscopy. By comparing the spectral characteristics of triple-based gun propellant sample and the total volatile, the optimal modeling spectrum of the total volatile was determined. The optimum spectral pretreatment method was finally confirmed, depending on the effect of spectra pretreating methods of triple-based gun propellant. The calibration model of triple-based gun propellant was established by partial least squares method(PLS), and the optimal principal factor of the total volatile model was chosen as 8, and the prediction ability of the model was demonstrated. The results show that the optimal spectral range is 5700-6100 cm-1, and the best spectral pretreating method is the combination of first order derivative and SNV.The determination coefficient of the calibration(RC2) is 0.9703, the root mean square error of calibration(RMSEC) is 0.1497;the determination coefficient of prediction(RP2) is 0.9628, and the root mean square error of prediction(RMSEP) is 0.1879. The ratio of the standard deviation of the validation set to standard error of prediction(RPD) of the total volatile model is 6.7. The model is applied to the detection of the total volatile content in the drying process of triple-based gun propellant, the average deviation of the predicted value is 0.025%. This method exhibited good predictive performance and repeatability, which can realize the accurate detection of the total volatile content during the drying process of triple-based gun propellant in 60 s.