Abstract Development of intrinsic electric charges at solid/liquid interfaces is still not fully understood and may generate large industrial damages by electrostatic discharges due to flow electrification. The pressure-wave-propagation (PWP) method is used to study solid/liquid interfaces in still and flowing conditions. Experimental results are shown with aluminum, brass, copper or pressboard in contact with demineralized water, salted water, glycerol or mineral oil. Salted water presents larger charge extent than expected. In still conditions with glycerol, copper gives more charges and pressboard has the largest charge extent. In flowing conditions, signal decrease seems attributed to physico-chemical time constant.

中文翻译：

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用压力波传播法直接观察固/液界面的电荷

摘要 固/液界面处固有电荷的发展仍未完全了解，并且可能由于流动带电而产生的静电放电对工业造成重大损害。压力波传播 (PWP) 方法用于研究静止和流动条件下的固/液界面。实验结果显示为铝、黄铜、铜或纸板与软化水、盐水、甘油或矿物油接触。盐水呈现出比预期更大的充电程度。在使用甘油的静止条件下，铜会产生更多电荷，而纸板的电荷量最大。在流动条件下，信号降低似乎归因于物理化学时间常数。