Dear Isogeochemists,
        I am trying to build a utility line (offline procedures) for
isotopic analyses of CO2. I would like to be able to obtain and purify CO2
from DIC-seawater, as well as CO2 for d18O analyses of seawater. I am aware
that two different settings may be implicitly involved, but I was wondering
if someone of you has already built any utility line with these things in
mind.  I have two questions in this regard:

1) The reason why I'm interested in combining the two designs (in one
system) is because I would not like to duplicate the costs in expensive
materials such pressure sensors and readout meters, valves, etc. by having
to build two different lines. It would be of great help for me if someone
could provide information about literature material that I can review or any
unpublished designs or sketches made for your own labs

2) While looking for vacuum gauges, I was able to find some in Cole Parmer's
catalog, but turned out to be expensive. The controller (for 3 sensors) is
$1,870 and each thermocouple sensor is $250 (x3=$750). The total for this
set of 3-sensors and controller is about $2,620 USD. Would you be able to
suggest any cheaper option (with different types and brands) with the
specifications needed for these applications?

I will greatly appreciate any help you can provide

Regards,

Jose






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Dr. Jose Carriquiry                                 . USA MAILING ADDRESS:
Instituto de Investigaciones Oceanologicas  . 1125 Loma Ave. #144-E099
Universidad Autonoma de Baja California     . Coronado, CA 92118
Apdo. Postal # 453                          . USA
Ensenada, Baja California, c.p. 22,800      .
Mexico                                      .
Tel (61) 74-46-01, ext 123                  .
Fax (61) 74-53-03                           .
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