[identity profile] ersatz-read.livejournal.com posting in [community profile] 1word1day
dewar (ˈdü-ər) noun

A glass or metal container, with a vacuum-like space between two walls to prevent heat transfer, often used for storing liquefied gases.  Also called a Dewar flask.

The thermos that keeps your coffee hot is a commercial version of the same thing:  a container inside another container, with an evacuated area in between as insulation.  It isn't a total vacuum - the walls of the container probably couldn't stand up to that.

In an MRI machine, the solenoid generating the magnetic field is inside a dewar of liquid helium.

I have a soft spot for dewars:  I used to set up physics lab classes for a living, and one of my first tasks was to fill dewars with liquid nitrogen (for the demos of freezing things and then shattering them).  That was a cool job with lots of toys; I would have stayed longer if it weren't for the mercury spills, rusty cans of benzene, misplaced radioactive sources, and sexual harrassment.  I didn't mind the iguana that sometimes ran loose in the hall.

Etymology:  Late 1800s, named after Sir James Dewar.
Except for similar pronunciation, it has nothing to do with Scotch.

(no subject)

Date: 2015-02-24 02:46 pm (UTC)
From: [identity profile] prettygoodword.livejournal.com
mercury spills, rusty cans of benzene, misplaced radioactive sources, and sexual harrassment ... the iguana that sometimes ran loose in the hall

Sounds like a physics lab, yup.

---L.

(no subject)

Date: 2015-03-02 11:50 pm (UTC)
From: [identity profile] elizamac212.livejournal.com
We use them in theatre quite a lot for fog and other special effects.
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