Desorption Of Analytes Research Articles

Desorption of organic analytes from activated carbon I: Factors affecting the process

A statistical analysis of the effects of loading, desorption volume at constant weight of solute, and the presence of other compounds on desorption efficiency was performed. For non-polar compounds and for a mixture of a polar and a non-polar compound, there was no effect of the presence of any one compound in the mixture on the desorption efficiency of the others. For polar compounds there was a dependency on the presence of other compounds. The implications of these findings and an explanation based on equilibrium considerations are advanced.

Desorption of organic analytes from activated charcoal II: Dealing with the problems

The previous paper in this series(1) dealt with the factors affecting the desorption efficiency. This paper continues by attempting to deal with the problems arising from the factors and interactions demonstrated. In particular, a mathematical treatment for linearizing the desorption efficiency-loading relationship is derived. The method successfully linearizes experimental data for 2-ethoxyethyl acetate and data in the literature for acetone. Data for the dependency of the desorption efficiency on desorption volume at constant loading for biphenyl is shown to fit the theoretical equation quite well. Finally, a method is described which eliminates the dependence of the desorption efficiency on the presence of other compounds for mixtures of polar compounds.

The field ionization properties of electrochemically produced Ni- and Co-emitters

The emission properties of Ni- and Co-emitters of the type recently introduced in analytical field ionization and field desorption mass spectrometry have been investigated. It was discovered that these properties are principally controlled by the bulk structure of the microneedles. After preparation the microneedles are insulators or poor conductors at room temperature since they are composed mainly of the oxide of nickel or cobalt respectively. The “activation” of these emitters by a heat treatment leads to the formation of electrically conducting microneedles.