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<font size="5" face="Garamond">Hi Kevin,</font> </p>
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<font size="5" face="Garamond"> Thanks for taking care of the centerpiece issue. I have not seen your post to the listserve, so it is likely it did not go through. Maybe try making PDF versions of the screen shots to make them smaller.</font> </p>
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<font size="5" face="Garamond">Michael</font><br><br>>>> <rasmb-request@list.rasmb.org> 5/4/2017 09:39 AM >>><br>Send RASMB mailing list submissions to<br>rasmb@list.rasmb.org<br><br>To subscribe or unsubscribe via the World Wide Web, visit<br><a href="http://list.rasmb.org/listinfo.cgi/rasmb-rasmb.org">http://list.rasmb.org/listinfo.cgi/rasmb-rasmb.org</a><br>or, via email, send a message with subject or body 'help' to<br>rasmb-request@list.rasmb.org<br><br>You can reach the person managing the list at<br>rasmb-owner@list.rasmb.org<br><br>When replying, please edit your Subject line so it is more specific<br>than "Re: Contents of RASMB digest..."<br><br><br>Today's Topics:<br><br> 1. question on wavelength calibration of AUC<br> (Jan =?UTF-8?Q?Kom=C3=A1rek?=)<br><br><br>----------------------------------------------------------------------<br><br>Message: 1<br>Date: Thu, 04 May 2017 15:39:25 +0200<br>From: "Jan =?UTF-8?Q?Kom=C3=A1rek?=" <honzakomarek@mail.muni.cz><br>To: rasmb@list.rasmb.org<br>Cc: Michaela Wimmerov? <michaw@chemi.muni.cz><br>Subject: [RASMB] question on wavelength calibration of AUC<br>Message-ID: <1493905164-175127-582.570291826986-54178@mail.muni.cz><br>Content-Type: text/plain; charset="utf-8"<br><br>Dear RASMB members,<br>I have a question related to wavelength calibration/accuracy of ABS optics.<br>There is suspicion that the calibration on our XL-I may be few nm out.<br><br>When looking at the peaks in wavelenght scan (emission spectrum of the lamp),<br>position of the 229 and 529 nm peaks are fine and within the specifications.<br>But when I use certified OD check solution (potassium nitrate), I can see the<br>maximum at 297 nm (instead of declared 302 nm). Also, when I perform the<br>wavelength scan of the protein sample, the maximum is not 280 nm, but 274-275<br>nm (and therefore I get lower signal for protein samples than I would<br>expect).<br><br>We did some other tests after discussions with Beckman technicians. The<br>reproducibility of the monochromator seems to be good (deviations within 1 nm<br>between several wavelength scans performed in a row) and the stray light check<br>was also OK. The details are enclosed. Unfortunatelly we don?t have holmium<br>oxide cell to independently verify the wavelengths.<br>I am aware of the limitations in wavelength accuracy on XL-A/I and know that<br>the wavelenghts will never be perfect, but I would expect that both<br>wavelenght/intensity check and OD check should give the same results...<br><br>Has anybody seen something similar or is anybody able to explain the<br>discrepancy? Any suggestion/comment would be appreciated. Thank you very much<br>and have a nice day :)<br><br>With kind regards<br>Jan Komarek<br><br><br><br><br>--<br>Jan Komarek<br>Central European Institute of Technology (CEITEC)<br>Masaryk University<br>Kamenice 5, A4/3.13<br>625 00 Brno, Czech Republic<br>-------------- next part --------------<br>A non-text attachment was scrubbed...<br>Name: wavelength_issues.docx<br>Type: application/vnd.openxmlformats-officedocument.wordprocessingml.document<br>Size: 73483 bytes<br>Desc: not available<br>URL: <<a href="http://list.rasmb.org/pipermail/rasmb-rasmb.org/attachments/20170504/6a4b123d/attachment.docx">http://list.rasmb.org/pipermail/rasmb-rasmb.org/attachments/20170504/6a4b123d/attachment.docx</a>><br><br>------------------------------<br><br>Subject: Digest Footer<br><br>_______________________________________________<br>RASMB mailing list<br>RASMB@list.rasmb.org<br><a href="http://list.rasmb.org/listinfo.cgi/rasmb-rasmb.org">http://list.rasmb.org/listinfo.cgi/rasmb-rasmb.org</a><br><br><br>------------------------------<br><br>End of RASMB Digest, Vol 52, Issue 1<br>************************************<br>
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