Introduction to Modern Liquid Chromatography, Third Edition part 89 pdf

... chromatogram have changed by different proportions, the detector settings may be at fault. Check the detector wavelength (UV detector, Section 4.4), interface adjustments (evaporative detectors, Sections ... can lead to the introduction of air bubbles into the HPLC system. Bubbles trapped in the pump head(s) can also cause baseline disturbances as the pressure fluctuates from one piston st...

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... rules, 583–584 structure vs. chromatography, 583–584 Proteomics, multidimensional liquid chromatography, 616–618 Protocol; see Validation, protocol Pseudocritical chromatography, 654 Pump(s), 104–113 active ... U-HPLC High-pressure liquid chromatography, 8 High-priced liquid chromatography; see U-HPLC High-speed liquid chromatography, 8 HILIC, see Hydrophilic interaction chr...

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... Hybrid Systems, 111 INTRODUCTION TO MODERN LIQUID CHROMATOGRAPHY Third Edition LLOYD R. SNYDER LC Resources, Inc. Orinda, CA JOSEPH J. KIRKLAND Advanced Materials Technology Wilmington, DE JOHN W. ... Lloyd R. Introduction to modern liquid chromatography / Lloyd R. Snyder, Joseph J. Kirkland. – 3rd ed. / John W. Dolan. p. cm. Includes index. ISBN 978-0-470-16754-0 (cloth)...

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... interaction chromatography HILIC hydrophilic interaction chromatography i.d. column or tubing inner diameter (mm) IEC ion-exchange chromatography IPC ion-pair chromatography k retention factor (same ... retention factor (same as capacity factor k  ); equal to (t R /t 0 ) − 1 k ∗ gradient retention factor; Equation (9.5) L column length (mm) LC-MS liquid chromatography–mass spectrometry L...

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... Accumulator-Piston Pumps An alternative design for the dual-piston pump is the accumulator-piston, or tandem-piston design shown in Figure 3.13d. In this case, one piston feeds into the other piston ... with either the dual-piston or accumulator-piston design. 3.5.1.3 Active Check Valve A final refinement in design can be applied to both the dual-piston and accumulator-piston pump designs. Th...

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... cycle time to just a few seconds. Three common autosampler designs are in common use: • pull -to- fill • push -to- fill • needle-in-loop 3.6.2.1 Pull -to- Fill Autosamplers The pull -to- fill autosampler ... detector. One way to avoid this is to use a switching valve to divert to waste the portion of the column effluent that contains most of the protein—usually the early portion of the...

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... operator’s manual, replacement of the needle seal every six months will help to avoid problems. The autosampler is the component of the HPLC system that is most likely to leak; it is wise to inspect ... proportioning-manifold replacement, injector rotor, detector lamp, tubing and fittings Factory-trained Proportioning-manifold repair, electronics, repairs involving module subassemblies,...

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... magnetic resonance Radioactivity Conductivity Chemiluminescent nitrogen Chiral 4.3 INTRODUCTION TO INDIVIDUAL DETECTORS The remainder of this chapter (Sections 4.4–4.16) provides a discussion of most HPLC detectors in use today. In Table 4.4, detectors are grouped ... selectivity, as well as the ability to change wavelengths during a chromatographic run. The most widely used detector in...

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... the interface between the stationary and mobile phases. Partition (Fig. 6.4c) considers the stationary phase to be similar to a liquid phase, into which the solute molecule dissolves. Notice that ... back onto or into the stationary phase—rather than extending into the mobile phase as shown. Presumably there is a decreased interaction with the column for solute molecules that are too lo...

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... software that facilitates method development. In this chapter we will Introduction to Modern Liquid Chromatography, Third Edition, by Lloyd R. Snyder, Joseph J. Kirkland, and John W. Dolan Copyright ... and L. R. Snyder, J. Chromatogr., 459 (1 989) 63. 17. B. F. D. Ghrist and L. R. Snyder, J. Chromatogr., 459 (1 989) 25. 18. V. Concha-Herrera, G. Viv ´ o-Truyols, J. R. Torres-Lap...

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