Hi, Joy:

The tech support from GVI suggested  using nickel wool in between glassy-C
and Ni-C to support Ni-C from dropping down the tube. It will help to get a
better peak. However, you may get a real fat peak if your carbon liner tube
has a hole in it.

Cheers.

Dachun Zhang
Isotope Lab
Zymax


----- Original Message -----
From: "Joy Davis" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, June 01, 2005 1:17 PM
Subject: [ISOGEOCHEM] Reuse of glassy carbon grit


> We are beginning to run 18-O on solid organics by pyrolysis to CO.  The
> (ceramic) pyrolysis column is packed with glassy carbon grit with ~10%
> nickelized carbon.  After about 150 samples, the peak shape deteriorates
> and the signal drops.  The column packing appears (visually) unchanged
> from the initial packing.  Can the glassy carbon be regenerated/cleaned
> and reused?
>
> Also, Alfa Aesar has two "types" of glassy carbon that differ primarily in
> their "maximum service temperature".  We (by mistake) are currently using
> the lower temperature glassy carbon (1100C).  What does maximum service
> temperature specify and what kind of change in behavior am I likely to see
> with the higher temperature (3000C) grit?
>
> Thanks.
> - Joy Davis
> Old Dominion University
> Norfolk, VA, USA
>