Electrical Current Monitoring Methods

There are three commonly used methods to measure the zeta potential, which involves pressure-driven flow, electrophoresis, and electroosmotic-driven flow, respectively. For the measurement of the specific surface conductivity, there are primarily two methods involving pressure-driven flow and electroosmotic-driven flow. In this entry, we will focus on the electrical current monitoring methods which can be used to measure the zeta potential, specific surface conductivity, volumetric flow rate, and electroosmotic mobility by employing electroosmotic flow with a solution displacement process. 

Electrical Current Monitoring Methods, Fig. 1 A typical current-time relationship measured for a 1 x TAE buffer solution replacing a 95 % 1 x TAE buffer solution in a 10 cm length of 100 pm i.d. capillary, under an applied electrical field of 7.5 kV/m... 

In the electrical current monitoring methods, a microchannel filled with mie electrolyte solution is brought into contact with two reservoirs, one of which has the same concentration as that in the microchannel and the other has a higher concentration. The electrical field is set up simultaneously so that the more concentrated mie will gradually replace the less concentrated one in the... 

Electrical Current Monitoring Methods, Fig. 3 Illustration of the velocity vaiiatirai in a parallel plate microchannel... 

Bubble Dynamics in Microchannels Electrical Current Monitoring Methods... 

Electrical Current Monitoring Methods, Figure 4 Schematic diagram illustrating the experimental set-up for measuring the current variation and the complete displacement time of a two-concentration system... 

Electrical Current Monitoring Methods, Figure 5 Comparison of the model-predicted average velocity with the experimentally determined average velocity by Eq. (2) and by Eq. (30) for a 1 x10 M KCI solution in a 10 cm length of 100 pm i. d. capillary... 

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