I'd also be very interested in seeing how vaporizing oxalic might somehow be
more effective than any other application method.
The link in the article goes to the JAR website, which does not seem to have
the issue at issue "up" yet - does anyone have a preprint?

Francis Ratnieks' reputation precedes him, so if this is spurious, it is
solely due to an over-enthusiastic university PR department.
For those unfamiliar with PR departments of all shapes and sizes, and their
treatment of otherwise highly-qualified findings presented with error bars
and everything, see this cartoon, which is only funny because it is the
unvarnished universal truth:

http://languagelog.ldc.upenn.edu/myl/ScienceNewsCycle.gif
http://tinyurl.com/qut4cj

>> the temperature that OA is sublimed at is pretty 
>> important, is there anything in your system to account for that??

> No there is not except for the fuel flow adjustment on the 
> pyropen; what I understand about OA is that it sublimes at 
> 314 degrees and the only way to make it reach a higher 
> temperature is under pressure 

I am pretty certain that no pressure is needed to quickly get OA heated well
above 314F.
I am also pretty certain that it is depressingly easy to do with any of the
vaporizers one can buy.
While the mass of the metal itself can at least slow the temperature rise,
what I have seen, heating coils that directly connect to
motorcycle/lawnmower batteries, there is nothing to stop overshoot or
hysteresis.  Looks like you could light your smoker with those things in a
few mins.

I'm not going to go get a SUMMA can and get the vapors analyzed, but my
notes from the CRC handbook say that when you overheat oxalic acid you get
either carbon dioxide and formic acid, or, at even higher temps, carbon
dioxide, carbon monoxide, and water vapor, so there is "overheating", and
then there is "way overheating".

Many moons ago, I built a precision thermostatically-controlled vaporizer
for oxalic with some left-over transistors, but never used it after Marion
Ellis' articles, papers, and demo and talk at EAS at Kent State, OH (2005?).
Dr. Ellis repeatedly and firmly made the point that safety concerns for the
beekeeper made vaporizing a very risky undertaking, and that there wasn't
any difference in effectiveness between the various methods of applying
oxalic.  

I remember that Medhat also mentioned that the commercially-available units
overheated the oxalic, but I do not remember if his own vaporizer had a
temperature control, or just "dose control" with the fan and the
pre-measured "pills".  Perhaps he will comment.

As for "dose control", one can easily measure powders with very high
accuracy at very low cost.  I do NOT recommend the cheap palm-sized and
paperback-book sized digital scales from China, as one gets what one pays
for when buying electronics.  Far better to trust the laws of physics, and
go with a mechanical scale, like one of these:

http://scaleman.com/calibron-twin-beam.html
http://www.amazon.com/Akurate-Ready-Assembled-Plastic-Balance/dp/B00XB52VBW

Buy one quick, as the supplier who made mine, Calibron, seems to have gone
kaput due to the cheap digital scales, so cheap pocket-sized balance scales
may soon become a collector item. These are very similar to the Calibron
unit I have used for years.  It is perfect for measuring small quantities,
and its accuracy is far better than the digital scales, because it is easy
to calibrate.  You'll need a small level to calibrate the scale - I use a
bullseye level, like this one:

http://www.amazon.com/Camco-25573-Bullseye-Level/dp/B000EDSSDY

There - for $10 you are measuring out oxalic very accurately. But don't use
that scale for anything else.  

And yes, for the record, cocaine sublimates at just a slightly higher
temperature than Oxalic sublimates, and this was called "freebasing" back in
the 1980s, so if you carry this gear around, you might want to keep the
oxalic in the store-bought container that is clearly labeled "oxalic" or
"wood bleach" or whatever.  Baggies might be a mistake.

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