Several people now have pointed me to the "special glass" capillaries
available from Hampton, Charles Supper, and apparently manufactured by
Hilgenberg.
http://hamptonresearch.com/product_detail.aspx?cid=19&sid=110&pid=323
http://www.charles-supper.com/en/page/product.cfm?idProduct=15
http://www.hilgenberg-gmbh.com/en/products/mark-tubes/?0=
The last web page mentions that their glass type 0140 is "Lindemann
glass".
However, Richard Gillilan was erudite enough to find the composition of
"Lindemann glass" in the "Glass Engineering Handbook" (E. B. Shand):
82.1% B2O3, 15.3% LiO2, and 2.6% BeO.
And by my calculations the attenuation coefficient of this stuff should
be 21.8 and 2.4 cm^-1 at Cu K-alpha and Mo K-alpha (respectively)
assuming it has the density of B2O3 (~2.5). This is a lot lower than
the values quoted for Hilgenberg's "0140" glass on their website: 97.4
and 10.5 cm^-1, which could only be explained if the glass density was
~11 g/cm^3 (about that of metallic lead).
So, I think either the data on the glass are misquoted or the stuff
Hilgenberg is selling is not actually the "Lindemann glass" that Richard
found.
I inquired with one glass manufacturer if they could make it, but they
came back that they didn't want to touch anything with "Be" in it, even
at 2.6%. Not sure how they feel about emeralds....
Nevertheless, it looks like "true" Lindemann glass is relatively soluble
in water, so it will not make for the good x-ray transparent, optically
transparent and water-tight window I had hoped.
-James Holton
MAD Scientist
James Holton wrote:
Does anyone know the formula or supplier of what was once called
"Lindemann glass"? It is a silicon-free high-boron glass that has no
elements in it heavier than oxygen. Used to be used to make clear
x-ray windows, but now I can't find anyone who sells it.
-James Holton
MAD Scientist
