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Lab Book 2014_05_12 Sample Frame Design and Missing Liquid Nitrogen

Lab Book 2014_05_12     Hamilton Carter

To Do this week in no particular order:
1.       Leak detect the glass and fiberglass Dewars
2.       Check on the availability of the can crusher
3.       Make drawings for sample stage
4.       Check for existing materials that might be used for the sample stage
5.       Find 240 V 3 phase outlet for the magnet power supply
6.       Get the power cord for the magnet supply
7.       Modify lab table
8.       Move magnet
9.       Continue review of the Nikolic paper concentrating on equations 8 - 11
10.   Continue work on the Thomas precession paper
11.   Check on replacement filters for the leak detector
12.   Move and test NaI detector
13.   Characterize source in Dewar with NaI detector
14.   Magnet test YBCO sample
15.   Find a source for x-ray film and developing

Done Today
Reseated the top and bottom seals on the fiberglass Dewar.  Spent some time brainstorming how to mount the sample in the fiberglass Dewar.

Dewar Design Decision:
The Dewar will not be cut or modified to house a larger sample than can be inserted through the neck.  The sample will be situated in the tail of the Dewar.

Brainstorming sketching.  The coil will be oriented with its axis of rotation directed horizontally.  The coil will be built into a curved fiberglass sample holder that will both reinforce the bottom of the coil and hold the sample.

Dewar Filling
Filled the liquid nitrogen storage Dewar. Empty it weighs 76 pounds and full it weighs in at 173 pounds.  Strangely, I’m unable to figure out how to get the liquid nitrogen to exit the Dewar today.  Opening the liquid or the vent valves produces no results, (haven’t tried both yet).  The pressure gauge reads 0 psi.  The Dewar is still slightly cold to the touch though and feels still feels heavier.


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