Optical errors in a liquid chromatography absorbance cell

Optical errors in a liquid chromatography absorbance cell.

The shadowgraph method is used to visualize mobile phase flow through a liquid chromatography absorbance cell with "Z" flow geometry. It is shown that mixing is incomplete in the cell. Composition gradients persist throughout the elution of any sample. The gradients systematically change as the sample flows through the cell. Additionally, window wedge angles are measured in several cells. The i...

Absorbance-modulation optical lithography.

We describe a new mode of optical lithography called absorbance-modulation optical lithography (AMOL) in which a thin film of photochromic material is placed on top of a conventional photoresist and illuminated simultaneously by a focal spot of wavelength lambda1 and a ring-shaped illumination of wavelength lambda2. The lambda1 radiation converts the photochromic material from an opaque to a tr...

Liquid chromatography with ultraviolet absorbance detection for the analysis of tetracycline residues in honey.

The separation of tetracyclines (TCs) using reversed-phase liquid chromatography (LC) is proposed. The use of an amide-based stationary phase prevents the interaction of tetracyclines with the residual silanol groups and thus avoids the appearance of tailed peaks. Detection was based on using an UV spectrophotometer and gradient elution with acetonitrile-oxalic acid as mobile phase permitted go...

Ion Exclusion Chromatography: Liquid Chromatography

terials, operated in a pressure-driven mode, plotted as a function of inverse temperature. This Rgure is intended to give some appreciation of the Suxes that are attainable; however, they are not normalized to a given partial pressure gradient or thickness of membrane, and thus the Suxes are not directly comparable. Taking a value of between 10 and 100 L m 2 min 1 as the level of oxygen Sux nee...

Liquid chromatography.