为进一步探究电穿孔理论机制,通过COMSOL建立单细胞电穿孔二维轴对称模型,该模型同时纳入表征微孔密度的电穿孔渐进方程和表征微孔动态演变过程的孔径变化方程,且模型的轴对称性使穿孔面积的计算更为准确,从而得到微孔的时空分布特性,...为进一步探究电穿孔理论机制,通过COMSOL建立单细胞电穿孔二维轴对称模型,该模型同时纳入表征微孔密度的电穿孔渐进方程和表征微孔动态演变过程的孔径变化方程,且模型的轴对称性使穿孔面积的计算更为准确,从而得到微孔的时空分布特性,并在此基础上探讨场强和脉宽对该特性的影响。结果表明:脉宽100μs、场强2 k V/cm的脉冲作用下,产生微孔7862个,穿孔面积达细胞表面积的6.3%,电穿孔各参量的时空分布规律与文献结果一致,从而可验证所建模型的有效性;在1~5 k V/cm范围内增大脉冲场强,微孔数与场强成正比,孔径则与场强成反比,孔面积与细胞面积之比从1.3%增至12.9%;对两组能量相同的纳秒脉冲和微秒脉冲进行比较,发现脉冲结束时前者产生的微孔数是后者的353.1倍,而在细胞膜上最靠近电极的点,后者的孔径是前者的19.3倍,说明纳秒脉冲有利于微孔数增加,而微秒脉冲有利于孔径扩大。仿真结果表明,微孔特性决定电穿孔的发生和发展过程,微孔特性的精确计算是阐释电穿孔效应的关键所在。展开更多
A two-dimensional axisymmetric model,with 8700 and 7500 quadrilateral elements for the fluid and substrate zone separately,was developed to simulate the impacting and flattening process. The volume of fluid technique ...A two-dimensional axisymmetric model,with 8700 and 7500 quadrilateral elements for the fluid and substrate zone separately,was developed to simulate the impacting and flattening process. The volume of fluid technique was employed to track the interface between the air and droplet. The relationships between the droplet pre-impact parameters and the flattening time as well as the flattening ratio were investigated by altering one of the parameters while remaining the others unchanged. The results show that the droplet height reaches its minimum value at approximately half of the spreading time,which also indicates the finish of vertical fluid flow at that time. The flattening ratio increases with the increase of the three pre-impact parameters-droplet diameter,temperature and velocity,even though the flattening time decreases when the droplet velocity increase.展开更多
文摘为进一步探究电穿孔理论机制,通过COMSOL建立单细胞电穿孔二维轴对称模型,该模型同时纳入表征微孔密度的电穿孔渐进方程和表征微孔动态演变过程的孔径变化方程,且模型的轴对称性使穿孔面积的计算更为准确,从而得到微孔的时空分布特性,并在此基础上探讨场强和脉宽对该特性的影响。结果表明:脉宽100μs、场强2 k V/cm的脉冲作用下,产生微孔7862个,穿孔面积达细胞表面积的6.3%,电穿孔各参量的时空分布规律与文献结果一致,从而可验证所建模型的有效性;在1~5 k V/cm范围内增大脉冲场强,微孔数与场强成正比,孔径则与场强成反比,孔面积与细胞面积之比从1.3%增至12.9%;对两组能量相同的纳秒脉冲和微秒脉冲进行比较,发现脉冲结束时前者产生的微孔数是后者的353.1倍,而在细胞膜上最靠近电极的点,后者的孔径是前者的19.3倍,说明纳秒脉冲有利于微孔数增加,而微秒脉冲有利于孔径扩大。仿真结果表明,微孔特性决定电穿孔的发生和发展过程,微孔特性的精确计算是阐释电穿孔效应的关键所在。
基金Project (50675072) supported by the National Natural Science Foundation of ChinaProject (E0610018) supported by the Natural Science Foundation of Fujian Province, ChinaProject (20062178) supported by the Natural Science Foundation of Liaoning Province, China
文摘A two-dimensional axisymmetric model,with 8700 and 7500 quadrilateral elements for the fluid and substrate zone separately,was developed to simulate the impacting and flattening process. The volume of fluid technique was employed to track the interface between the air and droplet. The relationships between the droplet pre-impact parameters and the flattening time as well as the flattening ratio were investigated by altering one of the parameters while remaining the others unchanged. The results show that the droplet height reaches its minimum value at approximately half of the spreading time,which also indicates the finish of vertical fluid flow at that time. The flattening ratio increases with the increase of the three pre-impact parameters-droplet diameter,temperature and velocity,even though the flattening time decreases when the droplet velocity increase.