Jenny等和Coleman等发现,当将参比电极的盐桥插入土壤悬液中时,带电荷的土壤颗粒可以使盐桥中阳离子和阴离子的淌度发生改变,因而在与土壤溶液的接触界面产生一个液接(扩散)电位。这个液接电位受一系列因素的影响。一般认为,这个液接电位与土壤胶体双电层的存在有关。在胶体化学上。普遍的概念是双电层的(有效)厚度为数百至数千埃。 Jenny et al. And Coleman et al. Found that when the salt bridge of a reference electrode is inserted into a soil suspension, the charged soil particles can alter the mobility of the cation and anion in the salt bridge and thus generate at the contact interface with the soil solution A liquid junction (diffusion) potential. This pick-up potential is affected by a number of factors. It is generally believed that this liquid pick-up potential is related to the presence of an electrical double layer of soil colloids. In colloid chemistry. The general concept is that the (effective) thickness of an electric double layer is hundreds to thousands of angstroms.