Here is one to check out-

Verardo, D.J, P.N. Froelich, and A. McIntyre, 1990, Determination of
organic carbon and nitrogen in marine sediments using the Carlo Erba
NA-1500 Analyzer, Deep Sea Research, Vol. 37, No.1, 157-165.

I have used various methods involving phosphoric and hydrochloric acid with
mixed results. This method originally proposed using aluminum capsules, but
this was a bad idea, to do the in-situ acidifications with sulfurous acid
(not sulfuric acid). You will need to use silver capsules. I have used it
for some time now with good results for carbon and nitrogen concentrations
and carbon isotopes (using Delta+/NA1500). Nitrogen isotopes work well too,
but I have had some problems with the nitrogen isotopes when org N conc are
below 0.1% and with samples that are recent (e.g. sediment trap samples up
to 18 months).

Others might have other successful ways to get the same or better results.

Cheers,

Dave

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David A. Mucciarone
Stanford University
Dept. Geological & Environmental Sciences
Building 320, Room 118
Stanford, CA 94305-2115
650-723-0817 (office)
650-725-2199 (fax)
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