Introduction to Modern Liquid Chromatography, Third Edition part 81 doc

... Modern Methods for Extracting Solids, 793 16.9 COLUMN-SWITCHING, 796 Introduction to Modern Liquid Chromatography, Third Edition, by Lloyd R. Snyder, Joseph J. Kirkland, and John W. Dolan Copyright ... removal but also to remove particulates. 16.4 SAMPLE PREPARATION FOR LIQUID SAMPLES Table 16.2 provides an introduction to sample preparation methods for liquid sam- pl...

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... into sample retention as a function of the solute, column, and mobile phase; it also represents more information than is usually required in practice. The reader may therefore prefer to skip to ... instant of time (as in Fig 2.8a), and this will cause the electrons in adjacent atom X to move as shown (due to coulombic repulsion). The result is an instantaneous dipole moment for both S...

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... meaning that pressure is required to force water into the pores. If the pressure P is insufficient to force a highly aqueous mobile phase into all the pores of the particle, solute molecules will ... is recommended to store the column with 100% acetonitrile as fill solvent. If the mobile phase is then changed to a lower value of %B while maintaining the column pressure, de-wetting is le...

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... 5.22b), the ligands are further apart, so as to allow access of both narrow and wide molecules (i and j) to the stationary phase. When a molecule has access to the stationary phase, steric exclusion ... surface area of the particle. 5.4.1.2 Shape Selectivity The following, minor digression examines two distinct forms of steric exclusion; for now, the reader may prefer to skip to Sec...

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... solutes 1 to 5 increases in proceeding from the Inertsil to the Symmetry to the Discovery column (note the retention ranges for peaks 1–5 in Fig. 7.9b, indicated at the top of each chromatogram ... C 18 column (5-μm particles); mobile phase, 13% acetonitrile-buffer (buffer is citrate plus phosphate); 2.0 mL/min; 35 ◦ C. Peaks for basic compounds 5 to 7 are shaded. Chromatograms based...

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... CONSIDERATIONS, 715 14.7.1 Thermodynamics of Solute-Selector Association, 715 Introduction to Modern Liquid Chromatography, Third Edition, by Lloyd R. Snyder, Joseph J. Kirkland, and John W. Dolan Copyright ... Reversed-Phase High Performance Liquid Chromatography,Aca- demic Press, New York, 1984. 169. A. M Striegel, W. W Yau, J. J Kirkland, and D. D Bly, Modern Size-Exclusio...

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... coworkers led in 1 981 to the first commercialized CSP with a DNB-phenylglycine derivative immobilized ionicly onto silica. Later this synthetic chiral selector was grafted onto silica via a covalent amide ... donor-acceptor phases have also proved to be valuable tools for SFC enantiomer separation [150, 151]. 14.6.8 Chiral Ion-Exchangers Chiral ion-exchangers utilize ionizable selectors...

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... Development for Gradient Prep-LC, 753 15.6 PRODUCTION-SCALE SEPARATION, 754 Introduction to Modern Liquid Chromatography, Third Edition, by Lloyd R. Snyder, Joseph J. Kirkland, and John W. Dolan Copyright ... Chromatogr. A, 906 (2001) 379. 62. P. Franco, A. Senso, L. Oliveros, and C. Minguill ´ on, J. Chromatogr. A, 906 (2001) 155. 63. T. Ikai, C. Yamamoto, M. Kamigaito, and Y. O...

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... leakage Damaged rotor seal Clean, replace rotor seal; may require stator replacement. External leaks not at fittings Worn rotor seal Clean, replace rotor seal Insufficient rotor -to- seal pressure Adjust Seal-pack ... replace Non-UV detector See Chapter 4 and operator’s manuals Table 17.4 Pressure Problems (Section 17.4.2): Symptoms and Sources Symptom Location/Symptom Possible Source Solution...

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... detector, see Detectors, MS Troubleshooting; see also Troubleshooting symptoms adsorption of sample, 818 819 air, removing from pump, 814 baseline drift, 817 best practices, 814 819 blockages, 814 bubbles, ... isolation, 819 –821 problem prevention, 811 819 problem symptoms; see Troubleshooting, symptoms quick fix, 812 813 records, 813 814 retention-time, changes, 836–838 siph...

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