I am using Acetanilide for a C/N weight percentage check standard on our 
new Costech EA coupled to a Delta V Plus.  I am interested as to whether 
there is a consensus as to its value for d15N and d13C.  I have run it 
alongside and calibrated it relative to IAEA and USGS standards, but I am 
finding that my Acetanilide values are different from one lab's data report 
that I had the opportunity to look over.  I'd be interested in knowing what 
values other labs are getting.  Or, if it is a moot point and Acetanilide 
isn't deemed a reliable isotopic standard, despite the reproducible results 
we obtain.  Thanks for any insight, and off list replies are welcome.



Lora L. Wingate
University of Michigan
Department of Geological Sciences
Stable Isotope Laboratory
1100 North University
1013 C.C. Little Building
Ann Arbor, MI 48109-1005