What about the concern of what the H2SO4 will do to the mass spec?  Does the
CF of He sufficiently sweep the acid away to the pumps and prevent any
corrosive reactions from occurring?   Or does the acid not make it past the
combustion tube?

Cyndi

**************************************************************
Cyndi Kester
U.S. Geological Survey
Denver Federal Center, Bldg. 21, MS 963
Denver, Colorado 80225

office:  303-236-0278
lab:     303-236-7694
fax:     303-236-4930
email:   [log in to unmask]


----------
>From: Bill Showers <[log in to unmask]>
>To: [log in to unmask]
>Subject: Atm Deposition Samples
>Date: Thu, Sep 23, 1999, 7:37 AM
>

> Dear Listmembers,
>
> I am trying to analyze some atm NH4 samples for N-15 that were collected in
> denuders and washed out of the collector with sulfuric acid.  NH4 samples
> in HCl freeze-dry nicely, can be rehydraded with a drop of RO water and
> placed on chemsorb particles for analysis in a EA-CFIRMS.  Does anyone have
> a technique for analyzing NH4 samples trapped in sulfuric acid?  What
> happens if you inject conc sulfuric acid into the EA combustion column?
>
> Thanks for any help.
>
> Bill Showers
> ----------------------------------------------------------
> William J. Showers
> Associate Professor
> Dept. of Marine, Earth, & Atm Sciences
> North Carolina State University
>
> (919) 515-7143 - voice
> (919) 515-7802 - fax
> [log in to unmask] - email