Hello All,

I was wondering if anyone out there has used the packed tubes to
pre-concentrate and a thermal desorption unit to measure carbon isotopes of
atmospheric hydrocarbons by GC-C-IRMS. If so, could you tell me the make of
the equipment used, if you found any isotopic fractionation from
pre-concentrating and/or desorption, and any references to published data
from the method.



Brian Jones

Assistant Research Scientist

& Lab Manager

Stable Isotope Ecology Laboratory

Dept. of Oceanography

Texas A&M University

College Station Tx. 77843

(979) 845-8916