基于微波透射技术的整包中药材含水率测量模型研究

Moisture content measurement model of whole package of Chinese medicinal materials based on microwave transmission technology

针对人工抽样检测整体代表性较低,烘箱检测含水率耗时长延误后续生产工期等问题,该文提出利用微波透射技术对中药材进行快速水分定量检测方案,并以8种不同类型的中药材为例,分析了该方案对中药材整包药材含水率检测结果的可行性和可靠性。在实验中,对每种药材分别利用最小二乘法对其微波吸收率-含水率建立测量模型。测试结果显示,微波透射测量含水率的技术可以实现五味子、酸枣仁、茯苓、地龙、百合、黄芩和炒鸡内金药材含水率的高精度测量,其中酸枣仁测量模型准确度最高,验证集的R^(2)和误差均方根分别为0.951 5和0.15%。同时,该研究发现地龙和炒鸡内金这2种动物药与五味子等植物药相比,动物药的微波吸收强度要弱得多,但是微波吸收率与含水率之间也有较好的线性关系,这也证明了该方法的普适性。而黄柏由于药材包装含有铁丝,不适合采用此方法。对于密度均匀、内部不含金属的药包,微波透射测量含水率的技术可以用于整包药材的水分检测,是一种有效的药材含水率检测的替代方法。

In view of the relatively low representativeness of manual sampling inspection, and long time-consuming in oven detection of moisture content, which delayed the subsequent production period, this paper proposed a scheme for rapid moisture quantitative detection for Chinese medicinal materials by microwave transmission technology, and took 8 different types of Chinese medicinal mate-rials as examples to analyze the feasibility and reliability of the scheme for the detection results of moisture content of the whole package of Chinese medicine. In the experiment, the least square method was used to establish the measurement model of microwave absorption rate-moisture content for each kind of medicinal material. The results showed that the microwave transmission measurement of moisture content achieved high-precision measurement of the moisture content of Schisandrae Chinensis Fructus, Ziziphi Spinosae Semen, Poria, Pheretima, Lilii Bulbus, Scutellariae Radix, and Galli Gigerii Endothelium Corneum. The measurement model of Ziziphi Spinosae Semen had the highest accuracy, and the R^(2) and root mean square error of the validation set were 0.951 5 and 0.15%, respectively. At the same time, this study found that the microwave absorption intensity of animal medicines including Pheretima and Galli Gigerii Endothelium Corneum was much weaker than that of plant medicines such as Schisandrae Chinensis Fructus, but there was also a good linear relationship between microwave absorption and moisture content, which proved the universality of this method. However, this method was not suitable for Phellodendri Chinensis Cortex because its package contained iron wire. For the whole package of medicinal materials with uniform density and no metal inside, the microwave transmission technology for moisture content measurement can be used to detect the moisture content, which is an effective alternative method to detect the moisture content of medicinal materials.