单基发射药生产过程中驱水棉水分含量的快速检测方法?

由于驱水棉的水分含量对单基发射药成型工艺有着较大的影响,采用近红外光谱分析技术对驱水棉水分含量进行快速检测。通过对比分析纯水、硝化棉(NC)、乙醇以及驱水棉的光谱图,确定了水分含量检测建模区域为5 015.6~5 224.8 cm~(-1)和6 525.9~7 008.7 cm~(-1)。比较不同光谱预处理方法,发现标准正态变量校正(SNV)、一阶导数和平滑的组合方法对驱水棉的光谱进行预处理效果最好。采用偏最小二乘法对水分含量建立定量校正模型,并对预测集样本进行预测和对模型进行重复性验证。试验结果表明:校正集和交互验证相关系数R2分别为0.995 4和0.994 4,预测均方根误差RMSEP值为0.039 0,对预测集的药料样本预测的平均相对误差为0.997%,模型的重复性良好,检测时间小于20 s,能满足单基发射药连续自动化生产工艺的要求。

Quick Measurement of Water Content of Dehydrated NC during the Manufacture of Single Base Propellant

Water content of dehydrated nitrocellulose(NC) has a great influence on the molding process of single base propellant. Near infrared diffuse reflectance ( NIR) analysis was used in the online detection of water content of single base propellant after driving water. Spectral region 5 015. 6-5 224. 8 cm-1 and 6 525. 9-7 008. 7cm-1 were selected to con-struct the model by analyzing the spectra of pure water NC, alcohol and single base propellant samples. The pretreatment method of SNV + 1st derivative + smooth was chosen by comparing different spectral preprocessing methods. Partial Least-Squares ( PLS) method was applied to set up linear mathematical model of water content, predict the predictive sets and verify the model. Results indicate that R2 of calibration set and prediction set are 0. 995 4 and 0. 994 4 respectively. RMSEP is 0. 0390. What’s more, the average analytical error is 0. 997% and the time for detection is less than 20 s. It can meet the needs of the continuous automatic production for single base propellant.