[RASMB] meniscus matching centerpiece

[Ariel Lustig]

Hi Michael Stoner and interested,
I hope I understood  your question !!
When  I worked  with the >> DELTA S' mode<< (differential sedimentation) we srcatched a capillary between the  two sectors , similar to the capillary of a double-sector-syntetic-boundary cell, just on the  lowest possible place. 
To compensate the  air  another  scratch on  top the sectors needed. We used an   Epon-Alum centerpiece.
The size of the capillary  depends on the viscosity  of the solutions you like to match. 
Worthwhile to do it in a workshop  where the operator has some magnification glass and sharp scratcher.
We tested it with  water and sugar water. usualy after few rpm's the miniscii are matched. 
A probleme may be if  no contact  should occur between the two  solutions, then we added first in each sector 20 or more mL of FC-43 ,(Flouro-carbo  fluid )Beckman sells this product= ro about 1.7gr/mL and it does not mix with water , but with  many  organic solvents (I have  a list). Befor  really use we made a lot of pre-runs for test. Sometime 
the capillary bloks  by some  dirt , then we open the centerpiece and rescratch a bit the capillary.
Sure  that on this way you sacrify a good  centerpiece.....ariel
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