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Hi Matt, Brian and others,

In the case of non site-specific analyses, another option is the  
reduction of N2O to N2 (and O2) on gold at 800-900°C. We routinely  
use a gold tube (ID .5mm, 50cm long) at a He flow rate of 1-2 mL/min  
and this converts it all.

see e.g. Kaiser et al., Anal. Chem., 2007, 79(2); 599-607.  DOI:  
10.1021/ac061022s for details (this method was then used for triple  
oxygen analysis of bacteria-made N2O out of nitrate, but we now also  
use it for nitrogen isotopes without any problem).

Samuel


On Nov 30, 2007, at 8:49 PM, Matt Black wrote:

> Hi Brian,
>
> I am dealing with this issue now as well. If site specificity is not a
> concern, see  Wrage et al. 2004. Distinguishing sources of N2O in  
> European
> grasslands by stable isotope analysis. Rapid Commun. Mass Spectrom.  
> 18,
> 1201-1207.
>
> They reduced N2O to N2 over Ni at 1150C, then used IAEA standards  
> for N2.
> I've been trying to do this using copper but cannot achieve complete
> reduction - however I only had a chance to try it at 650C. At the next
> opportunity I will increase the temperature and see if there is an
> improvement. Any suggestions?
>
> Matt
>
>



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