库尔勒香梨粗皮果振动频谱特性的研究

为了实现库尔勒香梨粗皮果的无损判别与检测,采用脉冲激励法测试了香梨正常果和粗皮果的振动频谱特性,分析了两种品质香梨响应主频率的差异显著性,并通过对两品质香梨石细胞含量的统计测量以及对果皮和果肉显微结构观察,探讨了粗皮果与正常果的响应主频率产生差异的本质原因。结果表明,正常果和粗皮果的响应主频率分别为(687.5±13.1)Hz和(775±19.4)Hz,存在显著差异(p<0.05)。粗皮果具有较高的响应主频率,其本质原因是其果表皮层致密、木质化细胞数量较多、含水率较低且其果肉中有大量分布的石细胞(团)和较多的木质纤维。 

Characteristics of the vibration spectral response of rough peel pear among Korla pear

The vibration spectrum characteristics of normal pear and rough peel pear were tested by pulse excitation,which were to realize the identification of rough peel pear among the normal pears. The difference significance of response dominant frequency between the normal and the rough peel ones was analyzed. The statistics of content of stone cells were analyzed. The microstructures of peel and flesh tissue of two kinds of pear were observed. The results showed that the dynamic signals were stable and reliable at the same detection point. Also,the responses of dynamic spectrum were consistent at different excitation points on the cheek and the line of equator with single excitation and detection. Response dominant frequency of the rough peel and the normal pear were(687.5±13.1) Hz and(775±19.4) Hz,respectively and there was significant(p <0.05) difference of dominant response frequency. Main reasons of the rough peel pear with the bigger response dominant frequency were that there were compact epidermis,lots of bonny cell,lower water content(wet base),a number of stone cell(mass) and lignocellulose widely distributed in flesh of the rough peel pear.