To Miguel and others,

Since Tim Heaton referred to our work on collagen, I should say that this
is not very relevant here, although the principles noted in that paper
(the effect of exchangeable H on delta-D values) is spelled out there.

The "correct" solution would seem to be that of Yapp and Epstein, and
other students of Sam who learned to replace the exchangable H's with
nitrate. These are to be found in such papers as

Epstein S., Yapp C.J., and Hall J.H. 1976. The determination of the D/H
ratio of non-exchangeable hydrogen in cellulose extracted from aquatic and
land plants. Earth Planet. Sci. Lett. 30:241-251.

The methods described there are applicable to cellulose only, not to whole
plants.

                                                Henry






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Prof. Henry Schwarcz, FRSC                              Tel: (905)525 9140
x24186
University Professor Emeritus
School of Geography and Geology                         Fax: (905)522 3141
McMaster University
Hamilton, Ontario, L8S 4M1                      email: [log in to unmask]
Canada

http://www.science.mcmaster.ca/geo/faculty/emeriti/schwarcz/index.html
http://socserv2.socsci.mcmaster.ca/~anthro/faculty/schwarcz.htm
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