Karl J. Bombaugh

A new gradient elution chromatograph

Abstract The differential refractometer, a highly sensitive and virtually universal detector for liquid chromatography, has been considered inoperable with gradient elution chromatography. However, with proper attention to solvent selection and instrument design, the versatile refractometer can be used with solvent programming. Therefore, a new general purpose gradient elution liquid chromatograph has been developed using dual columns with both a differential refractometer and an ultra-violet photometer as detectors.

Fast Gel Permeation Chroma tog raphy

Abstract A systematic study of the major factors influencing fast analysis by gel permeation chromatography is presented. The study included the effects of (a) solvent flow rate [1–35 ml/min], (b) sample concentration [0.05–0.5%], (c) sample molecular weight [41–411,000 mol wt] and (d) particle size of column packing [10–42μ]. The effect of the operating temperature at the high flow rates was also investigated.

Influence of support modificants on substrate selectivity in gas chromatography

Abstract It has been shown that solid support modificants as phosphoric acid and sodium hydroxide may do more than suppress peak tailing. They may alter substrate properties significantly. As binary or ternary mixtures with other substrates, they may provide a new dimension to substrate selectivity. Benefits may be achieved through the ability to alter substrate selectivity and through reduced analysis time.