Here is a puzzle on a lighter note that I am passing on: I guess
this guy (at Oregon U.) really needs a Rietveld phase analysis, but
that's not the kind of thing we do. Any suggestions ?
>I am on somewhat of a fishing expedition: We have found that jaws,
>claws, stings and other "tools" in a variety of arthropods and annelids
>contain up to 25% Zn by dry mass. I am not aware of any similar
>applications of Zn so we know nothing about the form that the zinc
>may be in. Exafs of specimens from a variety of organisms indicates
>that the coordination number is between 3.8 and 4.6 and that the
>first shell radius is between 1.95 and 2.0. The donors are either all
>O, all N, or N and O. The Debye-Waller factors were rather high
>(0.02) suggesting a heterogeneous coordination environment.
>Elemental analysis has eliminated all elements except C, H, O, and N.
>The zinc concentrations are too high for it to be an organic compound.
Alan H.
Alan Hewat, ILL Grenoble, FRANCE <hewat@ill.fr> tel (33) 4.76.20.72.13
ftp://ftp.ill.fr/pub/dif fax (33) 4.76.48.39.06 http://www.ill.fr/dif/