On 2005/07/20, at 2:09, Susan Waldron wrote:

> Dear all,
>
> what are the community thoughts on which acid to use to pre-acidify
> water samples planned for DOC extraction: HCl. H2SO4, H3PO4? I have
> seen them all used.  Which is most friendly on the CF-IRMS glassware?
> Also, acidify before or after filtering? To what pH ?  At least if it
> is after filtering  and DOM ppts. (such as humics at pH 2), then it
> can still be recovered as part of the sample.
> Are there concerns about loss of acid-sensitive material from the pool?
> Extracting only the HMW pool will eliminate the need for
> acidification -yes?- but what if you are interested in the whole pool?
>
> Thanks,
> Susan
> --
> *********************************************************
> Dr. Susan Waldron,
> NERC Advanced Research Fellow,
> Centre for Geosciences,
> Dept. of Geography and Geomatics,
> University of Glasgow G12 8QQ,
> Scotland.
>
> Tel: 0141 330 2413
> Fax: 0141 330 4894
> email: [log in to unmask]
> http://www.geog.gla.ac.uk:443/staff/swaldron
> *********************************************************
>
>
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