Wikipedia talk:Requests for arbitration/Depleted uranium/Evidence

message: I think that if the DU page is redone then a section devoted to the non radiological toxicity should be included. The work which you cited using Pu-244, and the work of Mary Neu should be included. I think that this proposal should be communicated to the other users who are debating the case.Cadmium 21:44, 10 March 2006 (UTC)
thread_title:  Actinide antidotes 

message: Back to my original point about sources, how are we going to choose which sources are NPOV and which are not? Cadmium 21:44, 10 March 2006 (UTC)
replies: text: I'm inclined to disregard any source with an economic stake in a controversial topic in which large sums of money are involved, and even peer-reviewed research which is too old to take into account, e.g., recent sharp uptrends in the congenital malformation rates in the children of the exposed.  I sure hope those level off, but if they don't, I'm not going to hesitate to say I told you so. --James S. 19:17, 15 March 2006 (UTC)
thread_title:  Sources 

message: James S. has recently indicated he will only provide diffs if the assertion is challenged. I should note that the burden of proof in arbitration cases here lies on the person making the assertion, and not the other way round. The assertion will almost certainly not be considered by the arbcom unless there is evidence (almost always in the form of diffs) provided. Johnleemk | Talk 16:09, 12 March 2006 (UTC)
replies: text: Thank you for pointing that out; you are correct.  However, the abundance of examples to choose from and the mere tangential nature of those premises to the case leave me ambivalent.  If I have time I will select diffs.  If the relevant assertions are challenged, then I will be more likely to do so.  I am not entirely sure whether I will or not, or just delete them as only vaguely relevant since very similar support was subsequently found in policy and guideline text.  An arbitrator asked for a longer evidence phase than my previous request, which would have closed things today.  I am comfortable with the case. --James S. 17:04, 12 March 2006 (UTC)

text: Removed as too tangental; the text from the WP:NLT policy is far stronger. --James S. 19:10, 15 March 2006 (UTC)
thread_title:  Regarding "Jimbo Wales has indicated that warnings of copyright violations are approved by the Foundation legal staff" 

message: Please leave these calculations alone, if you want to comment please do so in the sub section marked comments. I am making a point of doing the calculations in plain sight.
For the conversion of uranium metal to the monoatomic gas at STP, DeltaH = 533.0 +- 8.0 KJ mol-1
If we assume the reaction 2U + 3O2 to make 2UO3 then we can assume that the oxygen atoms (arrnaged in molecules are already in the gas phase. So no heat is required to form the oxygen gas.
Using Hess's Law, as the Delta H of formation of UO3 gas (from metallic U) is listed at -799.2 KJ mol-1, we can assume that the energy for the conversion of the monoatomic gas to the UO3 gas is 1332.2 KJ mol-1. This has allowed us to get to the point where we can draw a simple Born Haber cycle. This is rather mundane.
The next step is more interesting, assume that a uranium fire occurs in air (20% O2 and 80% N2). For the purposes of the calculation assume that the uranium oxide product is in the form of a gas.
2U + 3 O2 + 12 N2 --> 2 UO3 + 12 N2
We can expect that the reaction will generate 799.2 KJ mol-1
If we assume that no heat is transfered (adiabatic) system the it is possible to eastimate the flame temperture. I hope to goodness that this does not start a flame war, dire pun
The molar heat capacity of UO3 gas listed in my fav. source is 64.5 (plus minus 2) J K-1 mol-1
 states that the molar heat capacity of nitrogen is 20.8 J K-1 mol-1
So the heat capacity of 2 UO3 + 12 N2 will be (2 x 64.5) + (12 x 20.8) J K-1 mol-1
Which is 189.3 J K-1 mol-1 for each mole of uranium which burns. Call this Cx
Each mole of uranium which burns to make the gas, will give out 799.2 KJ (Delta H)
T = 298 K + (Delta H/Cx) = 298 + 4222 K = 4520 K
This is going to be very hot, and could cause uranium oxide gas to form for a moment. As the mixture is cooled by mixing with more air, the uranium oxide will then condense. The calculation which I have done is for a rare case of uranium being vapourised and then oxidised, this would happen in reactive spluttering where in an argon/oxygen gas at low preasure uranium atoms are spalled off of a surface by plasma discharge. So I think that it is reasonable to assume that uranium trioxide gas can be formed (for a moment) by burning uranium under a set of idealised conditions, but I expect that it will rapidly condense onto a surface.
Anyone who wants to is welcome to check my maths:) Cadmium
=== Comments on the Born Harber cycle ===
Flame temperature data. --James S. 20:14, 17 March 2006 (UTC)
thread_title:  Born Harber cycle 

message: Flame temperature data. --James S. 20:14, 17 March 2006 (UTC)
thread_title:  Comments on the Born Harber cycle