Efficiency and Resolution

The factors generally affecting column efficiency in other forms of liquid chromatography also apply to SEC, and column efficiency is calculated and expressed in the normal manner. The efficiency as calculated for a specific low molecular weight compound (e.g. an added solvent) will normally be higher than for a truly monodisperse polymer and the efficiency is normally reported for a solvent peak.

The resolution of two given monodisperse components can be sensibly expressed in a similar manner as for other forms of liquid chromatography but in SEC it is also possible to define a 'specific resolution' which relates to the theoretical resolution of two monodisperse polymers having one decade difference in molecular weight. The specific resolution will be dependent upon the gradient of the calibration (as expressed by log molecular weight versus elution volume). If the calibration is linear (on the log molecular weight scale) then the specific resolution will be constant across the molecular weight range.

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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