Introduction to Modern Liquid Chromatography, Third Edition part 22 potx

... directed to a photodetector, where it is monitored and converted to an electronic signal for data processing. Because fluorescence is emitted in all directions, it is common to monitor the emitted ... DETECTORS 169 lamp filter or monochromator photocell sample in sample out Figure 4.14 Schematic of a fluorescence detector. Dashed lines show optical path. expensive fluorometers use filters...

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... 158 4.3 Introduction to Individual Detectors, 160 4.4 UV-Visible Detectors, 160 4.4.1 Fixed-Wavelength Detectors, 163 4.4.2 Variable-Wavelength Detectors, 164 4.4.3 Diode-Array Detectors, 165 4.4.4 ... 113 3.6 Autosamplers, 113 3.6.1 Six-Port Injection Valves, 114 3.6.1.1 Filled-Loop Injection, 114 3.6.1.2 Partial-Loop Injection, 115 3.6.2 Autosampler Designs, 116 3.6.2.1 Pull -to- Fill A...

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... reasons: • to avoid an undesirable change in separation due to a sample size that is too large • to increase detection sensitivity for trace analysis, by using the largest possible sample size • to maximize ... Figure 2 .22 (assumes no mass overload). As sample volume increases from injections 1 to 4, the peak begins to widen and then develops a flat top. For Equation (2.27) and t...

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... pack- ing particles. To prevent particle aggregation, the interaction of the particle with the slurry liquid should be stronger than interactions between particles. For example, C 8 -orC 18 -modified particles ... as illustrated by the cartoon of Figure 5.25a, the liquid may be acceptable. However, if the particles tend to aggregate as in Figure 5.25b, the liquid is likely a poor cho...

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... METHOD ADJUSTMENT OR METHOD MODIFICATION, 561 12.8.1 pH Adjustments, 563 Introduction to Modern Liquid Chromatography, Third Edition, by Lloyd R. Snyder, Joseph J. Kirkland, and John W. Dolan Copyright ... UK, 1998. 2. L. R. Snyder and J. J. Kirkland, Introduction to Modern Liquid Chromatography, 2nd ed., Wiley, New York, 1974. 3. V. R. Meyer, J. Chromatogr. Sci., 33 (1...

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... poly-dimethylsiloxane or a polyacrylate [32, 33]. The fiber is dipped into the solution to be analyzed, and analytes diffuse to and partition into the coating as a function of their distribution coefficients. ... or embedded into individual disks. The plate is analogous to a 8 × 12 array of miniaturized SPE cartridges. The plates can be handled by robotic instrumentation to completely a...

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... way to flush particulate matter from the top of the inlet frit and restore normal peak shapes. After reversing the column, flow 20 to 30 mL of solvent through the column to waste (not the detector), ... stream due to partially blocked column-inlet frit. (c) Distortion of sample stream due to void at head of column. 042681210 Time (min) (a) (b) Figure 17.19 Split peaks attributed to...

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... ‘‘vertical’’ polymerization, 219 220 monomeric, 218–219, 232–234 phenyl, 226 polymeric, 218–219, 221 222 , 232–234 preparation, 218 225 selectivity; see Column selectivity stability, 220 222 steric protected, 220 221 synthesis; ... U-HPLC High-pressure liquid chromatography, 8 High-priced liquid chromatography; see U-HPLC High-speed liquid chromatography, 8 HILIC, see Hydro...

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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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... 651 13.10.3 Liquid- Chromatography Modes for Polymer Analysis, 653 13.10.3.1 Size-Exclusion Chromatography, 653 13.10.3.2 Interactive Liquid Chromatography, 653 13.10.3.3 Liquid Chromatography under Critical ... RPC- 5 Chromatography, 623 13.5.3 Hydrophobic Interaction Chromatography, 624 13.6 Separation of Carbohydrates, 625 13.6.1 Hydrophilic Interaction Chromatography, 625 1...

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