[time-nuts] OT, looking for a good science forum

[Graham / KE9H]

On 1/26/2013 1:29 PM, Paul Amaranth wrote:
>> Message: 4
>> Date: Sat, 26 Jan 2013 16:28:19 +0100
>> From: Fabio Eboli <FabioEb at quipo.it>
>> To: Discussion of precise time and frequency measurement
>> 	<time-nuts at febo.com>
>> Subject: Re: [time-nuts] OT, looking for a good science forum
>> Message-ID: <5ef3f142b075fcab38182666a4e5073b at quipo.it>
>> Content-Type: text/plain; charset=UTF-8; format=flowed
>>
>> Il 2013-01-26 14:58 Bob Camp ha scritto:
>>> Hi
>>>
>>> Platinum RTD's are a pretty good bet for -80C, they hold up well down
>>> there. For calibration, ammonia and acetylene both have triple points
>>> in the vicinity. I'd probably try ammonia first, but not for any good
>> Doesn't acetylene have a bad habit of dissociate when pure liquid?
>>
>> Fabio.
>>
> Yes, it's normally stored disolved in acetone.  It also spontaneously dissociates
> if pressures exceed 15 psig or 30 psi absolute.  That could put a real damper on your day.
>
>
Just pure acetone works well at dry ice temperatures.  We used crushed 
dry ice
in acetone as an alternative when the liquid nitrogen truck was late 
making its delivery
for the cryro lab.

--- Graham / KE9H

==