Re: "Dry" Dewars ?

[Johan Turkenburg <jpt@yorvic.york.ac.uk>]

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Hi,

We use Biotrek 3 (Statebourne Cryogenics) and Jencons CP100
dewars. The former holds four canes, with 4 xtals each, the latter
about 14 canes. Both seem to stay cold for very long (weeks).
Travelling with them is an adventure. Most airports etc. insist
on scanning them through their Xray machine. We put the dewars
through on their side (make sure it is really empty, drops of
LN2 make security people very unhappy). We always carry letters
on official paper stating the purpose of the trip and that all
samples are harmless (in our case this is true). We also contact
airports (both the operator and security) before we go, and
allow for extra check-in time. Putting the dewar in an old rug
sack makes it less obvious (people stare at you if you
carry a large metal cylinder). Once on the plane, the crew
sometimes puts the dewar in their wardrobe/cupboard, or allow
you to put it in front of you. This depends very much on the
crew, it seems. We have made a number of trips to Hamburg,
Trieste, Lund, Paris and Grenoble, and we have not been refused
travel yet.

Last time we flew with Lufthansa from Heathrow I got the
dangerous goods department to fax me a letter saying they
were all right with me carrying the dewar onto the plane.
Perhaps this is helpful when dealing with difficult crews.

I should add that we have not lost crystals until now, and
it certainly is a huge step forward from carrying trays with
crystals! It also makes use of synchrotron time a lot more
efficient.

Johan



-- 
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Dr. Johan P. Turkenburg
Protein Structure Research Group	 Phone (+) 44 1904 432596
University of York			 Fax   (+) 44 1904 410519
York YO1 5DD   UK			 Email: jpt@yorvic.york.ac.uk
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