Streaming potential measurements are performed to determine the zeta potential of flat surfaces, particles, or fibers. Although the zeta potential is a well‐defined property of solid surfaces in a liquid, there are indications that the absolute values of the zeta potential calculated using the Helmholtz‐Smoluchowski equation are affected by surface roughness and—in case of particle or fiber assemblies—their packing density. The study at hand investigates these influences using flat polymer surfaces with different roughness and topography and assemblies of basalt spheres. It was found that increasing roughness of the flat surface and larger size or smaller number of particles in particle assemblies result in flatter slopes of the streaming potential versus pressure and thus lower apparent absolute values of the zeta potential. The interpretation of streaming potential measurements should therefore not focus on absolute zeta potential values but on trends in pH‐ and concentration‐dependent measurements.

中文翻译：

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粗糙度和毛细管尺寸对通过流式电势测量获得的Zeta电势值的影响

进行流电势测量以确定平坦表面，颗粒或纤维的ζ电势。尽管zeta电位是液体中固体表面的明确定义的性质，但有迹象表明，使用Helmholtz-Smoluchowski方程计算的zeta电位的绝对值受表面粗糙度的影响，并且-在颗粒或纤维组件的情况下-它们的堆积密度。手头的研究使用具有不同粗糙度和形貌的玄武岩球体的平面聚合物表面来研究这些影响。已经发现，增加的平坦表面的粗糙度和粒子组件中更大尺寸或更少数量的粒子导致流动电势相对于压力的斜率更平坦，从而降低了ζ电势的表观绝对值。