Cyndi, In my experience H2SO4 never gets through the chemical traps on the C/N analyzer. Paul. At 12:14 PM 9/23/99 -0600, you wrote: >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 > > Paul D. Brooks. Dept. ESPM-Ecosystem Sci., 151 Hilgard Hall, MC 3110, UC Berkeley, Ca. 94720-3110. phone (510)642-3155 FAX (510)643-5098 (to Att. Paul Brooks)