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Chromatographic peak resolution is given by = + where t R is the retention time and w b is the peak width at baseline. The bigger the time-difference and/or the smaller the bandwidths, the better the resolution of the compounds.
In liquid chromatography, the mobile phase velocity is taken as the exit velocity, that is, the ratio of the flow rate in ml/second to the cross-sectional area of the ‘column-exit flow path.’ For a packed column, the cross-sectional area of the column exit flow path is usually taken as 0.6 times the cross-sectional area of the column.
Reversed-phase liquid chromatography (RP-LC) is a mode of liquid chromatography in which non-polar stationary phase and polar mobile phases are used for the separation of organic compounds. [ 1 ] [ 2 ] [ 3 ] The vast majority of separations and analyses using high-performance liquid chromatography (HPLC) in recent years are done using the ...
The second separation is rapid, allowing the introduction of subsequent fractions from the first column without mutual interference. Dallüge et al. [28] reviewed the principles, advantages and main characteristics of this technique. One of the main advantages is the very high separation power, making the technique ideal for unravelling the ...
A sample whose compounds concentrations are known is used to calibrate the TCD: concentrations are affected to peak areas through a calibration curve. The TCD is a good general purpose detector for initial investigations with an unknown sample compared to the FID that will react only to combustible compounds (Ex: hydrocarbons). Moreover, the ...
A high value for resolution corresponding to good separation of peaks is similar to the convention used with chromatography separations, [13] although it is important to note that the definitions are not the same. [14] High resolution indicating better peak separation is also used in ion mobility spectrometry. [15]
where is the number of theoretical plates (also called the "plate count"), H is the total bed height and HETP is the height equivalent to a theoretical plate. The material in packed beds can either be random dumped packing (1-3" wide) such as Raschig rings or structured sheet metal .
Chromatography software is called also Chromatography Data System. [1] It is located in the data station of the modern liquid, gas or supercritical fluid chromatographic systems. This is a dedicated software connected to an hardware interface within the chromatographic system, which serves as a central hub for collecting, analyzing, and ...