Hi Nick,

Your response to ISOGEOCHEM may be very useful to us. The top of the REF
peak is getting really ragged during the course of a run - but not the
sample peak. It used to deteriorate over the course of 20 or so samples,
but its doing it a lot quicker (we do have the trap up at 490). I did look
back at some of Allens runs from a couple of years back, and the top of
ref peak is not exactly flat then either. If its bad for the ref and not
the sample, it sort of implies its not a source issue - or does it? Do you
base a dirty analyser (flight tube and source) as a ramping of the signals
either side of the minor 1 doing a peak center scan, or by observing what
exactly?

cheers,

linda


> Hi Tim,
>
>   For ceramic parts boil in about 20% nitric acid till they look clean
> then boil 2 or 3 times in DI water, dry in an oven at 60'C or so.
>   For metal parts scrub them clean with Scotchbrite (the brown stuff in
> the sandpaper isle at Home Depot not the green from the grocery store).
> Then rinse in a decent grade of acetone and dry in an oven at 60'C. I'm
> not as familiar with Thermo systems but if you have an IsoPrime/Optima
> clean the repeller with diamond paste NOT Scotchbrite.
>   Cheers
>
>   Nick..
>
> Tim Prokopiuk <[log in to unmask]> wrote:
>   Greetings...
>
> Can anyone suggest a pure, reasonably priced chemical that we can use
> in the final rinsing step when cleaning an ion source to ensure no
> residue?
>
> Thanks in advance...
>
> Tim Prokopiuk
>
> -------------------------------------------------
> Tim Prokopiuk
> B. Sc. Geology/Technician
> Saskatchewan Isotope Laboratory
> Room 241
> Department of Geological Sciences
> University of Saskatchewan
> 114 Science Place
> Saskatoon, Saskatchewan, Canada
> S7N 5E2
> Phone: (306) 966-5712
> Fax: (306) 966-8593
> Email: [log in to unmask]
>
>
>
> Nick Collins
> President of North American Operations
>
> Mass Spec Solutions Inc.
> 305 Lincoln Avenue
> Rockville
> MD 20850
>
> [log in to unmask]
> Tel: (240) 601-5107
> Fax: (301) 294-6236
>
> www.massspecsolutions.com
>
> ---------------------------------
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