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Hi all-<br>
We, too, routinely use the Beckman charcoal-filled epon centerpieces at
60k without trouble unless there is a leak that empties only one
sector. If a leak like that happens, the centerpiece will be ruined
either because of a broken or a warped septum. The septum of the
Beckman centerpieces will remain intact and unwarped at 44k, which is
why they are rated for that speed. Peter's suggestion to check for
leaks is a good one. <br>
By using a different epoxy, thicker septum and a contoured bottom, the
SedVel60k centerpieces are rated for use at 60k. The thicker septum
places a premium on timing the lamp flash, which may be the cause of
the problem that Jack is having. They work well with the new
fluroescence and absorbance systems, where timing is taken care of in
software, and we have had no problems using them with the XLI
absorbance or interference systems on our instruments, but that is a
small sample size. I would be very interested in hearing the
experiences of others with them. <br>
Best wishes,<br>
Tom<br>
<br>
Allen H Pekar wrote:
<blockquote
cite="midOFD8B0BE7C.DA66D091-ON05257067.00630A1C-05257067.0063A00F@EliLilly.lilly.com"
type="cite"><br>
<font face="sans-serif" size="2">RASMB members: We had a cell leak
today where all the liquid leaked from one sector but little leaked
from
the other sector. As a result of spinning at 60,000rpm, the plastic
between the two sectors was bent. When the cell was taken apart,
the plastic returned to its original shape. Has anyone had this happen
and if so, is it safe to use the centerpiece? We mostly do velocity
runs at 60,000rpm. Thanks, Allen Pekar (Eli Lilly and Company)</font>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Department of Biochemistry and Molecular Biology
University of New Hampshire
Rudman Hall 379
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Durham, NH 03824-3544
Phone: 603-862-2459
FAX: 603-862-0031
<a class="moz-txt-link-abbreviated" href="http://www.camis.unh.edu">www.camis.unh.edu</a>
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</pre>
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