在肺泡的气-液界面上,存在着表面活性物质(SAM),由于其分子结构的不对称性,在界面上形成以亲水基在液相、疏水基在气相的定向排列的单分子膜,生理上有稳定脑泡和减小呼吸功等作用。肺SAM是多种磷脂、蛋白质和醣等物质的混合物,其中可降低水的表面张力的主要成份是卵磷脂。一些肺部疾病则由于肺SAM的缺乏所致。目前有关的研究工作之一即是寻找外源性治疗药物。一般的卵磷脂是作为研究的原材料,因此,有必要对其力学性质进行测量。 At the gas-liquid interface of the alveolus there is a surface active substance (SAM) which, due to the asymmetry of its molecular structure, forms on the interface a monolayer of hydrophilic molecules oriented in the liquid phase and hydrophobic in the gas phase Physiologically stable brain cells and reduce the role of respiratory work. Lung SAM is a mixture of a variety of phospholipids, proteins and sugars, among which the main ingredient that reduces the surface tension of water is lecithin. Some lung diseases are due to lack of lung SAM. One of the current research work is to find exogenous drugs. General lecithin is used as a raw material for the study, therefore, it is necessary to measure its mechanical properties.