Thank you all for sending me tips on H2 working standard. Those are
great help.
I have another question regarding H2 isotope analysis. I found a paper
on new agent for water reduction by Prof. S. Halas in IAEA report
(IAEA-TECDOC-825),entitled," Reference and intercomparison materials
for stable isotopes of light elements". In his article, he recommend
to use Mg-Pt instead of Zn and the agent gives us extraordianry
precision of hydrogen isotope analysis, let's say, better than +/- 0.2
permil. Is somebody tried his method and get similar results?  Are
there any new water reduction technique instead of them?  Thank you
all in advance for your gread advice.

Nori Tanaka
Graduate School of Environmental Earth Sciences
Hokkaido University
Sapporo, Japan