Gas Chromatographic Separation of Some Permanent Gases on Silica Gel at Reduced Temperatures

Abstract

Average of four readings for each run; exposure time, 2 minutes.Î o = 81.2 = 2.7 r per minute. It was measured from time to time. Value given is average of eight measurements; exposure time, 2 minutes.

Reducing contamination parameters for clumped isotope analysis: The effect of lowering Porapak™ Q trap temperature to below –50°C

“…Decreasing the temperature for gas chromatographic applications of some permanent gases results in an increase in the separation factor between contaminant gases and CO 2 . Our application is in principle similar to those of gas chromatography.…”

NMR Stability Assay for Amyl Nitrite Ampuls

“…The decomposition of amyl nitrite does not alter the number of methyl groups present, but it does reduce the number of -CHr O N 0 groups (14)(15)(16)(17)(18). This allows the degradation of the compound to be followed by determining the ratio of the number of -CHZ-ON0 groups to the number of methyl groups.…”

“…N20, NO, CO, COz, and at least 12 liquid components including water, amyl alcohol, isovaleric acid, isovaleraldehyde, amyl isovalerate, and amyl nitrate (14)(15)(16)(17)(18). In this paper, an NMR stability assay which is very rapid and which avoids most of the difficulties associated with previous methods is reported.…”

Weak-Link Versus Active Carbon Degradation Routes in the Oxidation of Aromatic Heterocyclic Systems. III

“…The retention times were identical to those of standard samples of the gases treated in an identical manner. Since this procedure was known to be useful in the separation of several gases [12], i.e., oxygen, nitrogen, carbon monoxide, carbon dioxide, nitrous oxide, nitric oxide, andmethane, it was concluded that no materials other than the carbon oxides were present in the gas phase degradation products.…”

“…It was identified by a comparison of its retention time in the gas chromatograph as well as its infrared spectrum [12] pyrolyzed, odichlorobenzene, the recrystallization solvent, was detected in the trapping system in minor amounts.…”