食管黏膜组织在轴向延伸下的摩擦特性研究

对食管黏膜组织沿轴向分别以不同的延伸率进行延伸,再通过往复摩擦试验近似模拟内镜前端进入食管的过程,研究了食管黏膜组织在不同轴向延伸率伸长下的摩擦性能变化.结果表明:从轴向无延伸到延伸率达到80%时,内镜前端与食管黏膜组织间的摩擦运行行为从食管黏膜组织只发生弹性变形的黏着状态变化到黏着和滑移的混合状态,摩擦阻力和能耗增大,摩擦系数增加.食管黏膜组织的摩擦学性能与其表面结构和力学性能密切相关.在沿轴向延伸率逐渐增加的延伸状态下,食管黏膜表面的皱褶被拉平,维持黏液润滑的特性变差;随着食管黏膜组织轴向延伸率的增加,黏膜组织的弹性模量增加,抵抗摩擦变形的能力增强,摩擦阻力增大.研究结果为临床胃镜诊疗的安全操作提供了理论依据.

Tribological Properties of Esophageal Mucosa under Axial Extension

In this study, the esophageal mucosa tissues were extended along their axial direction with different elongation rates, respectively. Subsequently, the tribological properties of esophageal mucosa tissue were investigated under these different elongation rates by using reciprocating friction tests to simulate the process of the front-end of endoscope passing into the gastrointestinal tract. The results show that the friction behavior between the front-end of endoscope and esophageal mucosa tissues changed from the sticking regime of elastic deformation of mucosa tissues to the intermediate regime of stick-slip when the axial elongation rate was from 0% to 80%, and the frictional resistance and energy consumption all increased, which led to the increase of friction coefficient. The tribological properties of esophageal mucosa are closely relevant to its surface structure and mechanical properties. When the elongation rate along the axial direction increased gradually, the ruffles on the surface of mucosa became flat and their ability to maintain the lubrication characteristics reduced. With the increasing axial elongation rate, the elastic modulus of mucosa tissue increased, and its ability to resist the deformation and the friction resistance enhanced. The results can provide the theoretical basis for safe operation in clinical diagnosis and treatment of gastroscope.