Methods of Chromatography

In most analytical applications of GC the mobile phase is continuously passed through the column and the sample is fed (or injected) into the system as a finite plug. This process is known as elution chromatography. If the conditions for the analysis are optimized the sample components can be separated completely from each other. If the sample is fed continuously onto the column with no added mobile phase, the process is known as frontal analysis. Only the first component to emerge from the column may be obtained pure, the other components being contaminated with earlier emerging components. A third technique, used occasionally in liquid chromatogra-phy (LC) but rarely in GC, is displacement development, which uses a strongly sorbed mobile phase to push (or displace) the components off the column. Each component can be obtained pure, but there is overlap between adjacent components placing a detector at the end of the column, which responds to some property of the sample molecules, produces a trace (the chromatogram) that is a plot of detector response against time.

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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