> Another tip:  Before running dD with the HDevice, perform all of the 
> d18O analyses first.  This will allow you to place samples with
similar 
> dD values near one another in the sequence, thereby reducing the
memory 
> effect of one sample on the next.

That's what we do with our water samples thanks to your advice.
This helped to reduce the memory to a minimum.
However, difficult to estimate the dD value of solid samples in a TC/EA
system.
I don't have an idea for a proper "forecasst".

Regards,
Robert


-- 
Dr. Robert van Geldern
Section 3: Geochronology and Isotope Hydrology
Leibniz Institute for Applied Geosciences (GGA-Institute)

GEOZENTRUM HANNOVER
Stilleweg 2
30655 Hannover, Germany

Phone: +49-(0)511-643-2313
Fax: +49-(0)511-643-3665
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