I stand corrected.


On Feb 28, 2007, at 2:58 PM, Steve Nelson wrote:

> Remy,
>
> Interesting question.
>
> I only kinda, sorta, know an answer, so I'll foolishly wade in anyway.
>
> We enrich tritium at low temperature by alkaline hydrolysis.  Our 
> system is only about 85% efficient in retaining 3H.  We don't measure 
> dD of the remaining water to calculate our enrichment.  We calibrate 
> our system directly by enriching standards.   But some folks do 
> measure enrichment by measuring dD and the water remaining after 
> reducing, say, 250 ml to 25 ml or so is extremely heavy.
>
> Of course, you are asking about oxygen rather than hydrogen.  But my 
> gut feeling is that unless you quantitatively electrolyze all of the 
> water and quantitatively recover all of the oxygen, the fractionation 
> could be large.
>
> On Feb 28, 2007, at 1:55 PM, Remy Okazaki wrote:
>
>> I would like to isolate oxygen from water for isotopic analysis, so I 
>> can
>> calibrate the oxygen standard in a mass spectrometer.  I was thinking
>> electrolysis to separate H and O, but would any fractionation occur 
>> during this
>> process?
>>
>> Conversely, if anyone knows where/how I can purchase an oxygen gas 
>> standard to
>> calibrate the mass spec, I would appreciate any input.  Thanks,
>> Remy Okazaki
>>
>>
> -- 
> *************************************************************
> Steve Nelson
> Associate Professor
> Dept. of Geological Sciences
> S-389 ESC
> Brigham Young University
> Provo, UT  84602
>
> 801-422-8688
>
> "Guns don't kill people, Dick Cheney kills people."
> George W. Bush:  "Decider in Chief"
> "Iraq burns.  We shop."  Bob Herbert
> **************************************************************
> Disclaimer for the feeble-minded:  It should be painfully obvious, but 
> the identification of my affiliation with Brigham Young University 
> does not imply that the University endorses any political or otherwise 
> partisan content of this message.
>
>
-- 
*************************************************************
Steve Nelson
Associate Professor
Dept. of Geological Sciences
S-389 ESC
Brigham Young University
Provo, UT  84602

801-422-8688

"Guns don't kill people, Dick Cheney kills people."
George W. Bush:  "Decider in Chief"
"Iraq burns.  We shop."  Bob Herbert
**************************************************************
Disclaimer for the feeble-minded:  It should be painfully obvious, but 
the identification of my affiliation with Brigham Young University does 
not imply that the University endorses any political or otherwise 
partisan content of this message.