[RASMB] laser delay jump

[Zhenli_Luo]

Dear RASMBers:
Recently a strange behavior occurred on our XL-I, described as follows:
Whilom, when using interference system in experiment, to obtain clear fringe
display, a laser delay was set to 180˚ for cell I at 3000rpm and adjusted to
about 180.5˚ at maximum speed on a 4-hole rotor, similar for other two cells.
But now it should be set to 180˚ at 3000rpm and about 177˚ at 60k rpm.
This situation began suddenly since an experiment conducted two days ago. A rotor
speed at 60k rpm, 20 degree C, both UV-Vis and interference detectors were used to
collect data at a time interval of 2mins, the data collected were alright at the
first hundred scans, then very curious data appeared, it seemed that there were no
signal since then, only noise was contained in data detected by both detectors, as
shown in attachment. I felt regret that I was absent at that moment so no more
detail can be provided.
I suspected that there may be problem with the overspeed disk, however there is no
crack or evident nick with the rotor and overspeed disk, and it works alright now
under new laser delay. But it may contain hidden risk, so I beg your suggestions.
Any word will be greatly thanked.


Zhenli Luo
29th, Apr.




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This letter is from Zhenli Luo at University of Science & Technology of China, in Hefei, Anhui, P.R. China.
96 Jinzhai Road, Hefei, Anhui 230026, P.R. China
Hefei National Laboratory for Physical Sciences at Microscale, USTC.
Laboratory of Polymer Colloid and Solution 7004
Tel: +86-551-360 6741
Fax: +86-551-360 6743
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