Ben,

Try

Fischer Analysen Instrumente GmbH
Braherstrasse 25-27
D-04347 Leipzig
Germany

E-mail: [log in to unmask]


They are interested to expand their instruments to ecological
applications. It sounds promising.

Al the best
Rolf


On 21.10.2004, at 22:22, Ben Ellert wrote:

> I would appreciate feedback (sources, costs, utility) of infrared gas
> analyzers (IRGA) that might work for continuously monitoring CO2
> concentration
> and ideally atom% 13C in a plant growth labeling chamber.  With our
> conventional IRGAs it seems that CO2 moves out of the absorption
> window as 13C
> enrichment increases (perhaps up to 50 atom%).  Ideally we could
> continuously
> circulate chamber air through the IRGA so we could adjust the CO2
> input (and
> 13C enrichment) in concert with photosynthetic uptake.  Apparently
> IRGA's are
> widely used to measure 13CO2 in discrete breath samples for H. pylori
> testing,
> but I'm interested in uncomplicated and afforadable IRGA's for lower
> resolution work.
>
> Thanks much,
> Ben Ellert - Agriculture & Agri-food Canada, Lethbridge
>
__________________________________
Dr. Rolf Siegwolf
Lab for Atmospheric Chemistry
Stable Isotopes and Ecosystem Fluxes
Paul Scherrer Institut
CH-5232 Villigen PSI
Switzerland

e-mail: [log in to unmask]
Phone: +41 56 310 2786
Fax     : +41 56 310 4525

http://lac.web.psi.ch/
http://sibaebasin.web.psi.ch/
__________________________________