Talk:Protactinium/Archive 1

Structure
I think that α-Pa a tetragonal structure I4/mmm not orthorhombic, see e.g. http://cst-www.nrl.navy.mil/lattice/struk/a_a.html. --Axiosaurus (talk) 18:42, 24 February 2008 (UTC)

is there a mistake in the isotope decay data
Look closely. It says Pa-234 metastable has two decay modes, one to U234 directly which releases 2.29 MeV of energy, and one isometric transition to Pa-234 which releases 0.0694 MeV of energy, while regular Pa-234 always decays to U-234 with 0.23 MeV of energy. Note, however, that 0.23+0.0694 is NOT 2.29. Not even close. Perhaps the Pa-234 decay to U-234 should in fact be 2.23 MeV and not 0.23? Unless perhaps one pathway involves the release of two neutrinos (that's one energetic damn neutrino to take away 2 MeV!) or some other particle not accounted for, the total energy in either pathway to U-234 should add up to the same thing by the laws of thermodynamics.

174.25.84.93 (talk) 23:12, 20 April 2010 (UTC)
 * Data seem Ok, and this might answer your comment (different final 234U states). Materialscientist (talk) 04:20, 21 April 2010 (UTC)

atomic mass units not adding up
in the section:

Protactinium-233 is formed upon neutron capture by 232Th. It further either decays to uranium-233 or captures another neutron and becomes uranium-235. Whereas both products are useful for the breeding process, and are the desired nuclear fuel, their production from protactinium-233 is rather inefficient: 233Pa has a relatively long for the process half-life of 27 days and high cross section for neutron capture (the so-called "neutron poison"). Thus instead of rapidly decaying to the useful 233U, a significant fraction of 233Pa atoms absorb more neutrons, converting into undesirable higher actinides. In this process, they consume neutrons from 232Th, degrading the reactor efficiency.

it would seem that 233U gains *one* neutron, and is converted to 235U rather than the 234U that one might expect. I'll admit that I never got around to taking a college level nuclear physics course, but I was under the impression that protons and neutrons were worth one AMU each. I suspect that there was some confusion, as the normal decay path is for 238U to emit an alpha particle in decaying to 234Th, which then emits a beta particle to decay into 234Pa, which then captures a neutron to become 235Pa, which can then emit another beta particle to become 235U.

Anyone out there with a better background who can confirm this?

ck DocKrin (talk) 22:30, 16 March 2011 (UTC)
 * It seems the description was correct, but had a typo of 235U instead of 234U. Corrected that, with a reference. Thanks. Materialscientist (talk) 04:00, 17 March 2011 (UTC)

Image appears false
The image of Protactinium on this page appears to be a CGI image of some white powder - it is not a real photograph. Please remove 137.205.26.238 (talk) 22:33, 22 November 2008 (UTC)
 * I've removed the image. --Itub (talk) 11:57, 24 November 2008 (UTC)


 * rsc.orgis the source of the Protactinium image. So where is the copy right for that image?


 * It's fake! Lanthanum-138 (talk) 11:26, 28 April 2011 (UTC)

Decay modes
This section is so full of errors I suspect it is intentional. Check out alpha and beta error under isotopes if you need any convincing. It is totally back the front.

Johnpaterson1234 (talk) 03:45, 26 October 2012 (UTC)
 * Thanks. The infobox was wrong for years and nobody bothered to check. I've adjusted the modes and values per CRC Handbook (92nd edition) and http://www.nndc.bnl.gov/chart (they are close to CRC, but I suppose they have more accurate values). I took only the major decay mode - for all the listed isotopes it accounted for >90% of intensity. Materialscientist (talk) 04:32, 26 October 2012 (UTC)

External links modified
Hello fellow Wikipedians,

I have just modified 3 external links on Protactinium. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
 * Corrected formatting/usage for http://periodic.lanl.gov/91.shtml
 * Added archive https://web.archive.org/web/20080923135135/http://www.nndc.bnl.gov/amdc/nubase/Nubase2003.pdf to http://www.nndc.bnl.gov/amdc/nubase/Nubase2003.pdf
 * Added archive https://web.archive.org/web/20080307023843/http://www.ead.anl.gov/pub/doc/protactinium.pdf to http://www.ead.anl.gov/pub/doc/protactinium.pdf

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

Cheers.— InternetArchiveBot  (Report bug) 20:21, 14 September 2017 (UTC)

Untitled
Article changed over to new WikiProject Elements format by schnee. Elementbox converted 10:47, 17 July 2005 by Femto (previous revision was that of 20:28, 13 July 2005). 13 July 2005

Information Sources
Data for the table was obtained from the sources listed on the subject page and WikiProject Elements but was reformatted and converted into SI units.