How to obtain peak capacity

Separations in the normal-phase mode allow to get higher peak capacities at identical pressure or identical capacitites as in this figure at lower pressme due to the lower viscosity of the eluent at 20 °C, hexane has a viscosity of 0.33 mPa s but water has 1 mPa s (Section 5.1). We can also compare the time needed instead of the pressure. Normal-phase separations are faster than the ones on reversed phases if the goal is identical capacity at identical pressure. 

Gradient separations allow to reach much higher peak capacities than shown here with isocratic runs. 

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A new topic is now included Chapter 20 about quahty assurance. Part of it could be found before in chapter 19 but now the subject is presented much broadly and independent of Analytical HPLC . Two chapters in the appendix were updated and expanded by Bruno E. Lendi, namely the ones about the instrument test (now chapter 25) and troubleshooting (now chapter 26). Some new sections were created 1.7, comparison of HPLC with capillary electrophoresis 2.11, how to obtain peak capacity 8.7, van Deemter curves and other coherences 11.3, hydrophilic interaction chromatography 17.2, method transfer 18.4, comprehensive two-dimensional HPLC 23.3, fast separations at 1000 bar 23.5, HPLC with superheated water. In addition, many details were improved and numerous references added. 

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