| In Part I of this dissertation, a three-column variant of ion chromatography (IC) called replacement-ion chromatography (RIC) is introduced. The method employs a column that replaces solute ions with another ionic species that can be sensitively detected by a suitable detector. Conceptually, this new approach to IC detection offers several important advantages over conventional IC methods. Ion replacement allows otherwise selective detectors to be used as general detectors for IC. Moreover, if appropriately chosen, these detectors can provide lower detection limits than the conductivity detector. In addition, the integrated detector response is universal.;These potential advantages were first explored for the determination of ions by a cation-replacement method. Here, the replacement ion, Li;The merits of an anion-replacement method were examined with IO;In Part II of this dissertation, a microwave-induced plasma (MIP) produced by a device called a "surfatron" is explored as a detector for nonmetals dissolved in aqueous solutions. Solutions were introduced with a glass-frit nebulizer and a desolvation system. The detection limits of several nonmetals are in the low-ppm range. Good precision (RSD ;The plasma was also explored as an element-selective detector for capillary supercritical fluid chromatography. Optimal plasma conditions are discussed for sulfur emission. In addition, the effects of two mobile phases (CO... |
