Gas chromatography

Abstract

review surveys developments in the field of gas chromatography since publication of the last review in this series (496) and covers the years 1970-71. Gas chromatography continues to be one of the most active areas in analytical chemistry. A recent report by the American Chemical Society ( 791) is based on the employment specialty choices of 84,925 chemists and chemical engineers who reported to the 1970 National Register of Scientific and Technical Personnel, an activity of

Gas chromatographic degradation of several drugs and their metabolites

“…In this paper, we report the results of a detailed study on the changes in the chromatographic parameters such as separation factors, HETP curves, and thermodynamic functions, induced by modifying the adsorbtive surface of Sterling FT with various amounts of different liquid phases. The choice of Sterling FT among the large variety of graphitized carbon blacks has been made by the considerations: (1) surface area (15 m1 2 34567/g) is good for reliable coatings at <1, where is the ratio between covered and uncovered surface, but still allows the elution of rather high-boiling compounds; (2) good mechanical resistance to ensure reproducibility of columns made with the same mesh range.…”

The Effect Analysis of Carrier Gas Flow Rate on the Rapid Gas Chromatographic Separation System

“…Two repeated injection tests were performed to determine the retention time and peak width of the mixture, and the mean value was calculated. Separation of the mixture is mainly achieved by using the separation of the system; the relative physical and chemical properties such as the boiling point, polarity, and adsorption and desorption of each component are fixed [ 12 ]. After separation and detection of dimethyl sulfide and toluene mixture, data processing was performed using the software of the upper computer to calculate the retention time and peak width of dimethyl sulfide and toluene at different flow rates, and the separation was calculated according to equation ( 3 ).…”

Kinematic contraction and expansion of chromatographic bands

“…Recalling that 5rp/5t and bfq/bt (when &t -* 0) represent the instantaneous velocities of the rear of component p and the front of component q, to be denoted by Upr and Uq{, respectively, expression Id can be written in the form (* -urP+1)x,ip> + -Vg+1)x/"-?,=o (2) p-i 9=0…”

“…These coupled with the requirement of plug injection are not only regarded as the necessary but also sufficient conditions to ensure resolution of the mixture into sharp rectangular bands, each having the same width as that of the initial unseparated "mixed-band." Apart from practical realization of these conditions, there are conceptual difficulties, especially the very existence of equilibrium in a flow system, the departure from which has been quantitatively discussed previously by one of the authors (2,3).…”