Cucchiella Rodolfo, Falini Giuseppe, Ferri Massimo, Stracquadanio Milena, Trombini Claudio
Dipartimento di Matematica--Università di Bologna, Piazza di Porta S. Donato 5, 40126, Bologna, Italy.
J Environ Monit. 2009 Jan;11(1):181-6. doi: 10.1039/b806940a. Epub 2008 Nov 7.
Mathematical morphology is a tool for extracting image components that are useful for representation and description. The technique consists of a set-theoretic method of image analysis providing a quantitative description of geometrical structures. A simple application of mathematical morphology to a bi-dimensional processing of TEM images of airborne particles allows us to distinguish between particles grown and/or transported in atmosphere under dry conditions or in rainy days by a simple comparison of the corresponding image form factors. The form factors range in the 0.385-0.031 interval in the case of particles sampled in rainy days, and in the 0.103-0.006 interval in the case of non-rainy conditions. The same classification criterion was applied to filters collected under dry conditions and plunged in water. The results demonstrate that a morphological change may be artificially induced to the particle structure. The artificially wet particles, indeed, display an apparent contraction of their structures evidenced by a two-fold increase of the average values of their form factors. The last experiment roughly simulates the impact of particles on membranes of the respiratory tract.
数学形态学是一种用于提取对图像表示和描述有用的图像成分的工具。该技术由一种图像分析的集合论方法组成，可对几何结构进行定量描述。将数学形态学简单应用于空气中颗粒物透射电子显微镜图像的二维处理，通过简单比较相应的图像形状因子，我们就能区分在干燥条件下或雨天在大气中生长和/或传输的颗粒物。对于在雨天采样的颗粒物，形状因子在0.385 - 0.031区间，而在非雨天条件下则在0.103 - 0.006区间。同样的分类标准应用于在干燥条件下收集并浸入水中的过滤器。结果表明，颗粒物结构可能会被人为诱导发生形态变化。实际上，人工湿润的颗粒物显示出其结构明显收缩，这通过其形状因子平均值增加两倍得以证明。最后一个实验大致模拟了颗粒物对呼吸道膜的影响。
