摘要
目的应用Low -Shear40流变仪对手术后恢复期病人痰的粘弹性、触变性等指标进行测定与分析 ,确定测量方法 ,得到痰的滞后环和应力衰减曲线。方法以湿法测定为主 ,测定前尽量除去标本中的唾液、血液和气泡等。切变率在12s内从0线性增大到10S-1 再线性降低到0,记录此过程的扭矩变化。应力衰减曲线采用突加一个10S -1的切变率 ,测量随后120s时间内的扭矩变化。粘弹性采用简谐振荡的频率扫描法 ,频率扫描由0.01Hz～5Hz,叠加切变率为1S-1。相应的角频率为0.0615S-1～31.42S-1,振荡角为0.9849°。结果痰的屈服应力很大 ,约为8.94Pa,应力变化呈单纯的指数衰减 ,但衰减很慢 ,120s后应力仅衰减了约50%。剪切模量在0.01Hz～0.5Hz范围内有四个局部峰值和三个局部谷值。应力与应变的相位差随频率的变化与剪切模量相对应。结论探讨了痰标本的粘弹性、触变性测定方法 ,得到了痰的滞后环。
Objective With the Low Shear-40 rheometer the methods of measuring viscoelasticity and thixotropy of sputum were confirmed and the viscoelasticity, thixotropy, hysteresis loops and torque-decay curve in cancer patients were measured. Methods With the wet methods, saliva, blood and air bladder were removed carefully from sputum. When measuring hysteresis loop, shear rate increased from 0 to 10s-1 within 6s and decreased form 10s-1 to 0 within another 6s. Torque-decay curve was measured within 120s by a sudden adding shear rate of 10s-1. Viscoelasticity was measured with frequency scanning method. The frequency was scanned from 0.01 Hz to 5Hz with shear rate of 1s-1,relevant angular frequency was 0.0615s-1 to 31.42s-1, surge angular was 0.9849°. Results The yield stress of sputum was about 8.94Pa. When a sudden shear stress affects the sputum, the change of stress was a slow simple exponential attenuation. The shear modulus and phase difference reached local maximum value at four sequencies. Conclusion Our results explore the methods of measuring sputum viscoelasticity and thixotropy and obtained shear modulus and rheograms with cancer.
出处
《中国微循环》
2000年第2期97-100,共4页
Journal of Chinese Microcirculation
基金
"九五"军队医药卫生科研基金!(NO :98M143)
关键词
痰
流变学
粘弹性
触变性
癌症
Sputum Rheology Viscoelasticity Thixotropy
