2DmX[LeffXLtotMV 2D

Thus the maximum column efficiency in CE is proportional to the mobility and voltage, while inversely proportional to the diffusion coefficient. Considering that mobilities of ions range between 10 "4 and 10 "3 cm2 V "1 s"\ diffusion coefficients from 10-7 to 10~5cm2s_1, and an applied voltage up to 104 V, the attainable theoretical plate number would be in the order of 105-106, which is much higher than any conventional HPLC approach. Eqn [8] also suggests that in principle CE should be well suited for the separation of high-mass charged particles such as biopolymers, since their diffusion coefficients are extremely low. This has been demonstrated in the most successful resolution of DNA fragments and proteins where plate numbers of 106 have been reached. It should be emphasized m that eqn [8] is only valid under the precondition that longitudinal diffusion plays a predominant role among the various band broadening mechanisms. In other words, to achieve the maximum column efficiency, the electrophoretic separation should be carried out in such a way that all the other potential band dispersions are curbed well below the magnitude of the longitudinal diffusion effect.

Injection related volume overload During sample injection, a finite volume of sample is placed onto the capillary. The length of this starting plug will contribute directly to the final band width. Treating the original band as rectangular in shape, the variance of this plug can be expressed by:

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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