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Dear Bethany,

Your email prompted me to revisit an old paper by Malcolm Dole, who, among
other things, studied oxygen isotopes in atmospheric oxygen.

This paper describes the early pain in measuring isotopes in gases that
arenąt carbon dioxide.

Malcolm Dole, G.A. Lane, D.P. Rudd, D.A. Zaukelies,
Isotopic composition of atmospheric oxygen and nitrogen,
Geochimica et Cosmochimica Acta,
Volume 6, Issues 2­3,
1954,
Pages 65-78,
ISSN 0016-7037,
https://doi.org/10.1016/0016-7037(54)90016-2.

Other considerations: air is full of nitrogen and oxygen, so any small
vacuum leak contaminates your sample. Hydrogen isotopes require converting
to H2 gas‹either with awful chemicals or very high temperatures.

Marilyn 



Check out my new blog at https://isotopequeen.blogspot.com/

Dr. Marilyn L. Fogel,
Distinguished Professor and Wilbur W. Mayhew Professor of Geo-Ecology
Director of the Environmental Dynamics and Geo-Ecology Institute
(http://edge.ucr.edu/)
Dept. of Earth and Planetary Sciences
University of California Riverside
900 University Ave.
Riverside, CA 92521
[log in to unmask]
Phone: 209-205-6743

From:  Stable Isotope Geochemistry <[log in to unmask]> on behalf of
"Theiling, Bethany" <[log in to unmask]>
Reply-To:  Stable Isotope Geochemistry <[log in to unmask]>
Date:  Friday, September 6, 2019 at 8:36 AM
To:  <[log in to unmask]>
Subject:  Re: [ISOGEOCHEM] The commonality of CO2 analyses

Thanks for the responses (and the toilet seat history!).

These are great references, Gerry. I agree: CO2 is just fantastic to work
with, and is both important (geologically and environmentally) and readily
available. I had wondered if CO2 was particularly easy to deal with in terms
of ionization, so it was good to see your confirmation.
I suppose there is not really a point in trying to cite all of the early
work with CO2 just to state it's importance in a manuscript, and just accept
(and appreciate) it's long reign. Though I may try to dig up some of the
early papers on ionization...

As always, thanks all,
Bethany

Bethany Theiling, Ph.D.

Research Scientist
Planetary Environments Laboratory, Code 699
NASA Goddard Space Flight Center
Greenbelt, MD 20771


From: Stable Isotope Geochemistry <[log in to unmask]> on behalf of
gerard olack <[log in to unmask]>
Sent: Wednesday, September 4, 2019 6:42 PM
To: [log in to unmask] <[log in to unmask]>
Subject: Re: [ISOGEOCHEM] The commonality of CO2 analyses
 
HI Bethany--



For pre-Nier mass spectrometry, see the review by Bleakney (1936):

http://scitation.aip.org/content/aapt/journal/ajp/4/1/10.1119/1.1999047
<https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fscitation.
aip.org%2Fcontent%2Faapt%2Fjournal%2Fajp%2F4%2F1%2F10.1119%2F1.1999047&data=
02%7C01%7Cbethany-theiling%40UTULSA.EDU%7C5cb614d9b1d74012405b08d73191a62d%7
Cd4ff013c62b74167924f5bd93e8202d3%7C0%7C1%7C637032373967243380&sdata=er%2FBC
U0PKSe3uyTxkZiF%2Fnr4rP3QA%2FEj9Kp1Zpqrl38%3D&reserved=0>



Friedman and O'Neil (USGS 440-KK) have a brief history of standards and
fractionation factors:

https://pubs.er.usgs.gov/publication/pp440KK
<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpubs.er.u
sgs.gov%2Fpublication%2Fpp440KK&data=02%7C01%7Cbethany-theiling%40UTULSA.EDU
%7C5cb614d9b1d74012405b08d73191a62d%7Cd4ff013c62b74167924f5bd93e8202d3%7C0%7
C1%7C637032373967253371&sdata=rielDUsJYyLV0VsUW7RLupcbfk8Y%2FHFPEfXqDwbZLFk%
3D&reserved=0> 



Gonfiantini has a nice write up of reference materials (and yes, it was a
toilet seat) and early days of CO2 isotopic measurements:

http://www-naweb.iaea.org/napc/ih/documents/Newsletter/issue_25.pdf
<https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww-naweb.
iaea.org%2Fnapc%2Fih%2Fdocuments%2FNewsletter%2Fissue_25.pdf&data=02%7C01%7C
bethany-theiling%40UTULSA.EDU%7C5cb614d9b1d74012405b08d73191a62d%7Cd4ff013c6
2b74167924f5bd93e8202d3%7C0%7C1%7C637032373967253371&sdata=D%2F72XHkzrOnqUvg
Ixz9wZm6NmzHUE6JRa2UOXW%2BPLr8%3D&reserved=0>



CO2 is used because it is easy to work with--but I don't have a good
reference off the top of my head.  It can be frozen down using LN2, and
cleaned up cyrogenically, i.e. pump away residual air.  You do not need a
Toepler pump, though mercury pistons were used for pressure balancing.  And
since it can be introduced directly as a gas into the mass spectrometer, you
can use electron ionization.  A number of early papers dealt with ionization
in the source and source tuning--especially important in stable isotope
analyses since consistent signal strength was needed to compare amounts.

Dewar flasks were invented in 1892.  Commercial scale liquid air (liquid N2)
plants were starting to be built in the 1930's.  Electronics were well
enough developed to build stable stable isotope mass spectrometers, so all
the pieces were in place.



CO2 is also readily available from geological samples--just react carbonates
with acid (phosphoric).  And it can be equilibrated with water, so it can be
used to determine the 18O composition of the water.



good luck...



take care,

gerry




On 9/4/2019 10:18 AM, Theiling, Bethany wrote:
> Hi everyone,
> 
> I've been reading up on the history of mass spectrometry (fascinating!),
> especially with regards to the technological advancements and scientific
> discoveries made by Alfred Nier. It seems that many of us stable isotope
> (geo)chemists consider measurement of CO2 isotopologues and specifically d13C
> measurements to be the 'easiest' (or perhaps the most common?), new
> instruments seem to be first developed for CO2 measurements (and then tested
> for the other systems), and d13C measurements typically have the highest
> precision. Indeed, Nier and Gulbransen laid the foundation for carbon isotope
> measurements (published) in 1939. There are lots of great scientific reasons
> for measuring CO2 isotopologues and/or d13C of some material.
> 
> My question is, from a philosophical, scientific, or technological standpoint,
> where does this (historical) proclivity for d13C and/or CO2 measurements come
> from? 
> 
> I look forward to your thoughts!
> 
> Bethany
> 
> 
> Bethany Theiling, Ph.D.
> Research Scientist
> Planetary Environments Laboratory, Code 699
> NASA Goddard Space Flight Center
> Greenbelt, MD 20771
>