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Wilson and Ackerman never state any combustion products because they have done no combustion. So citing them for combustion is not OK. The Ackerman is only researching Oxides in general and the transformation. They state that there is no UO3 vapor present due to the calculations mentioned above. Sublimation from UO3 nor from U3O8 will ever occure at temperatures below 500°C which is OK with the calculations for the partial pressur of UO3.
You said someone should claim Ackemann wrong! He is right! He does chemical transport reaction from U3O8 nothing more and nothing less. Wilson is also right for Uraniumoxide interconversion. But they all give low vapour pressure for the oxide.
The condensation of the product is described by the gas law and the mass law. The calculationes done from me and others indicate that at standart conditions no UO3 gas is present. So why mention it at all. This is the poinz of the whole thing molecular UO3 is not woth mentioning! Because the vapour pressure of it is so close to zero that even if you assume its toxic nobody will ever take up more than a few molecules. So if you state that condensation is nearly 100% with only a few molecules in gasphase the whole UO3 mythe (flying around for weeks and gasous UO3 major product of combustion) can go!-- Stone 10:05, 29 March 2006 (UTC)
There is no statement that U03 is formed as main combustion product. Ackerman, Willson, Chatillon, Nakajma, Capone, Capone, Arai, Guido all start from different oxides and so the sublimation or transport reaction mentioned for the Ackermann paper fit to the problem and again we get nothing else as no UO3 vapor present due to the calculations mentioned above. Sublimation from UO3 nor from U3O8 will ever occure at temperatures below 500°C which is OK.
To give back the compliment you made: The rest is shown as object fraud, because your plasma burning uranium oxide is a nice try but the exact paper giving the plasma burning experiment of uranium and the composition of the gas phase is no where given. So who is doing the object fraud?
Back to the point:To give back the compliment you made: The rest is shown as object fraud, because your plasma burning uranium oxide is a nice try but the exact paper giving the plasma burning experiment of uranium and the composition of the gas phase is no where given.-- Stone 09:04, 29 March 2006 (UTC)
Another point why should be the most exothermic product be the one favoured at high temperatures? My chemistry knowledge says: high temperatures favour the less exothermic or endothermic reactions. Example: Burning coal: (Boudouard-Equilibrium)
400°C 99/1 600°C 77/23 800°C 10/90 1000°C 1/99
With this numbers UO would be the main compustionproduct.
So where is the literature indicating that this law of reactions is not true for the uranium oxides.
Stating that the uranium trioxide reacts different if it is created by plasma or sublimation simply shows a lack of chemical knowledge and is a point no chemist will ever accept.
Born Haber cycle is easy to understand and as simple as going up 2 flours with elevator and than 7 by the stairs or rocket up to the 12 flour and than 3 down with the fire ladder you end up in the same flour.
Everything else would give nosense. So first oxidising than sublimation than condensation makes no difference to sublimation of uranium than oxidation and than condensation.
The condensation from gas phase follows the rules of mass law. The air is oversaturated with uranium trioxide and the molecules have to follow the law and condense. This condensation is absolutely independent from which source the uranium trioxide molecules come from. How should the information stick to each molecule when to condense? -- Stone 09:29, 28 March 2006 (UTC)
Note: Please sign your comments with --~~~~ or at least four tildes. -- James S. 03:16, 29 March 2006 (UTC)
The point is and will always be why should a molecule with a low vapour pressure be a gas at normal conditions? A source for a example of this kind of behaviour would be good-- Stone
The micro particles flying around nobody will deny, the caesium-137 or so from the spain steel factory and the atomic tests is also flying around, but as particles or condensed to dust particles.
The dust particles go into the lung if they have certain diamater, this is shown in many studies. Germany has problems with microparticle dust from diesel motors. Studies show that this particles and up in the lung.-- Stone 07:04, 29 March 2006 (UTC)
Problem finding UO3 infrequently ignored in Gmelin 8 1977 Uranium C1 page 98 can you state if this is the right page number?-- Stone 07:13, 29 March 2006 (UTC)
Lets start wit the equation it self: can be found in [1]
log p= (((1.821 ± 0.075)· 104)/T) + 6.84 ± 0.58 log p= (((1.856 ± 0.016)· 104)/T) + 6.928 ± 0.103
I choose the first equation because it gives the higher pressure for UO3 gas.
log p= (((1.821 ± 0.075)· 104)/T) + 6.84 ± 0.58
Lets state 300K as the temperature (26°C or so)
putting in the numbers gives:
log p = -53.86
put both sides in the power over ten (native speaker needed)
p = 10-53.86 atm
p = 1.38 · 10-54 atm
convert from atm to Pa (1 atm = 101325 Pa)
p = 1.3985 · 10-49 Pa (N/m2)
Assuming that the laws of ideal gas are good for this problem
(which they are not, because the the condensation and the interaction between the molecules give even lower pressure for real gas at lower temperature than expected by the ideal gas euqaution)
p V= n R T
n = (p · V) / (R · T)
n =(1.3985 · 10-49 N/m2 · 1 m3)/ (8.314472 J · K-1 · mol-1 · 300 K)
n = 5.57 · 10-53 mol
so this is the number of mol per cubic meter of uranium trioxide.
1 mol = 6.023 · 1023 particles
So to get the number of particles in one cubic meter simpl multipie the numbers.
6.023 · 1023 5.57 · 10-53 = 3.35 · 10-29 particle per m3
Other way to point this numer is you need 2.98 · 1028 m3 to find on single atom of UO3.
Volume of earth 1.0832×1012 km3 = 1.0832×1021 m3 so even if the whole earth would be atmosphere there would be no molecule founnd in it. 600 times earth volume and you find your UO3.
The equations are right and the condensation follows this patter. Where am I wrong? This leads to no molecules in the gas phase after cooling at all.-- Stone 10:32, 29 March 2006 (UTC)
Does Cotton give UO3 or simnply uranyl than it has to go!-- Stone 11:10, 29 March 2006 (UTC)
Lets sat it the way it is:
Burning DU gives U3O8 UO3 UO2 in changing quantities. (Acording to differt literature) The condensed particle from this are small and do not settle qickly. The elevated radiation from UK during GW2 shows this clearly. Small particles get into the lung and due tue the fact that Uranyl compunds like UO3 dissolve quicker than U3O8 the toxicity of them is severe. This is absolutly OK.
My oppinion is, that DU is chemical warfare and only because its cheper than tungsten to poisen Irak and Yugoslavia with it is crimainal. The other nations use tungsten for ammunition and they know why! Is DU ammunition used in traing grounds in the US? I think they would not dare to do so, because theay get lawyers crawling around everywhere. -- Stone 11:27, 29 March 2006 (UTC)
The only thing to do is to get the first sentence to a state which makes clear that both cited references do not do the research indicated in the sentence bevor.
Which is critical in my point of few.-- Stone 11:33, 29 March 2006 (UTC)
The transport reaction was OK I think. This is a example for UO3 molecules and could stay. The matrix experiments with single UO3 molecules where also resonable. -- Stone 16:51, 29 March 2006 (UTC)
The references section is almost as long as the article itself, and a fair number of the articles cited there seem not to be used. 129.215.195.81 14:57, 30 March 2006 (UTC)
Given the recent phenomina of fresh anons reverting away source-supported statements, and apparently planning to delete sources, above, as their only edits here, I propose partial protection of the recent dispute-tagged version for a short while. Are there any objections? -- James S. 22:55, 30 March 2006 (UTC)
Does anyone care to defend this? -- James S. 22:32, 31 March 2006 (UTC)
From a realy good article about: Volatilization of urania under strongly oxidizing conditions Journal of Nuclear Materials 346 (2005) 312–318 C.A. Alexander
If the oxygen partial pressure is held constant and the temperature raised, then the composition will shift to a lower value of the O/U ratio. Since the higher oxidation state at a specific temperature will have a more negative free energy,
This states higher temperature makes substances with more free energy unstable! -- Stone 08:07, 31 March 2006 (UTC)
Ther should be headlines for
like in most other articles. This article is and will be a mess! I will try to build up a new one User:Stone/Uraniumtrioxide leaving out
Which can be but in from somebody else!-- Stone 08:18, 31 March 2006 (UTC)
is more accurate, taller, has many fewer characters than the graphic, and so it takes less time to load. -- James S. 19:51, 31 March 2006 (UTC)
Urine tests for isotope ratios are worthless, because the isotopes translocate at different rates. Anything less than chromosome analysis after one year is worthless. -- James S. 19:58, 31 March 2006 (UTC)
{{ fact}}?? The isotope effect for U-235 and U-238 is minimal, this isn't hydrogen and deuterium we are talking about. 82.41.26.244 20:25, 31 March 2006 (UTC)
There is an currently edit war going on if the gas phase structure should be placed above or below the solid-state structure. We also now have a pretty graphic of the molecule in the gas phase.
My take on the matter:
I have examined the work cited by James S. which was by C. Busby. After reading it I have come to the conclusion that it is less trustworthy than papers printed in more traditional chemical, physics or biological journals.
The paper is Busby, C. and S. Morgan (2006) "Did the use of Uranium weapons in Gulf War 2 result in contamination of Europe?" European Biology and Bioelectromagnetics, 1(5), 650-668.
Why would the molecule be T shaped ? I know that a matrix isolation study has been cited, but in a condensed phase packing effects could distort the molecule from the shape found in the gas phase. Valence Shell Electron Pair Repulsion theory ( VSEPR) which is one of the best predictive tools for simple molecules would predict a C3 trigonal shape like that of BF3. Cadmium 17:27, 1 April 2006 (UTC)
Filling the article up with solid polymorph forms, while removing the source-supported statements about gas production is such obvious bias. This bias is made all the more obvious with the lung solubility reference to "elimination" -- a pharmokinetic term meaning excretion, urination, or perspiration, from the Morrow (1972) reference to lung fluid solubility -- certainly a much larger, plainly factual error than removing the reference to the controversial Busby article. It is so sad that so many people want to participate in supressing information about the gas phase. Why not just remove all references to water vapor from articles involving boiling water? -- James S. 20:52, 2 April 2006 (UTC)
And another thing, Cadmium, why are your oxygen diameters so tiny? Your diagrams are seriously misleading. -- James S. 20:58, 2 April 2006 (UTC)
Cadmium: I have these further questions about your recent reversion which is just a copy of others' reverts:
The Uranium trioxid GAS also found its way into the uranium page! As combustion product!-- Stone 09:11, 5 April 2006 (UTC)
I found no indication that there is no source for Uranium trioxide as primary combustion product. So I will delet the unsourced citations.-- Stone 13:49, 5 April 2006 (UTC)
I think that each polymorph does need its own subsection, I intend to add more on each one. For some forms more than one diagram is needed. James has compressed the solid state chemistry into too small a space for it to be clear. I agree that under some comditions that UO3 gas can exist, but the solid state is more important as the vast majoirty of the chemistry of UO3 is of the solid. Cadmium
As there is only the combination of wilsom and ackermann this is simply not enough to claim combustion product. The found combustion product in kuwait tank fire is probably UO3 which is als not enough to claim UO3 combustion product.-- Stone 08:10, 6 April 2006 (UTC)
Ther is no combustion mentioned! Cotton states uranyl compounds nothing else! If I state they rise from the quantum vacuum, this would also be possibel but also unreferenced!-- Stone 07:31, 7 April 2006 (UTC)
Are you afraide to have a opponent with high level experience of Chemical warfare? The G. Schrader working group was always my favorit for phosphor chemistry and the Labwork of Haber and Grignard on sulfide chemistry are also a highlight of french and german chemistry!-- Stone 08:02, 11 April 2006 (UTC)
Let's also mention that the vapor pressure of UO3 at 980 °C is 10 nanobars or to. Someone who breathes in the gas has other things to worry about that gaseous combustion products of uranium.
To mention pot in a long section is a little bit more than necesarry. The whole article will benedit from som tidy up.-- Stone 08:10, 6 April 2006 (UTC)
After redoing all the literature and adding use and Production I think the structures of the delta and the beta form could have their place on the supplementary page? These pictures are good, but they take a lot of space and load.-- Stone 10:29, 6 April 2006 (UTC)
The links to the scanned and downloaded pdfs of www.bovik.org have a questionable legal status here in Europe, and I do not know what the rights owners would think if they find them linked to this article. We know them an most of us red them so why keep them on the front page? Put them to the talk page or so than anybody interested in the little uraniumoxide controversy can download them from there.-- Stone
If you realy want I write a letter to elsevier, that you use their articles on this page. -- Stone 07:29, 7 April 2006 (UTC)
Still have the feeling that the structures take mor place than necesarry-- Stone 07:33, 7 April 2006 (UTC)
I realize this is a big edit war (in which I have no desire to get involved), but I condensed the production section and removed the other two times it is brought up.
Here are my suggestions for the article. It would be preferable for this to follow the WikiChemicals template, but if I were to ignore that for a second:
Right now this article is a big mess. Olin
However, having said that, I don't understand Cadmium's latest structure calculations, so I'm going to move them here to the talk page. -- James S. 07:58, 9 April 2006 (UTC)
It is possible by bond valence calculations [2] it is possible to estimate how great a contribution a given oxygen atom is making to the assumed valence of uranium. Zachariasen, J. Less Common Met., 1978, 62, 1-7. Lists the parameters to allow such calculations to be done for many of the actinides.
The formula to use is
For uranium binding to oxygen the constants Ro and B are tabulated in the table below. For each oxidation state use the parameters from the table shown below.
Oxidation state | Ro | B |
---|---|---|
U(VI) | 2.08Å | 0.35 |
U(V) | 2.10Å | 0.35 |
U(IV) | 2.13Å | 0.35 |
It is possible to do these calculations on a scrap of paper (old skool method) or software which does it can be obtained free of charge. [3] [4]
Using a 6Å x 6Å x 6Å box with the uranium atom in the centre the bond valence calculation was performed for both U1 and U2 in the delta phase of uranium trioxide. It was found using the parameters for U(VI) that the calculated oxidation states for U1 and U2 are 6.78 and 6.13.
R is the distance from the oxygen to the uranium atom s is the contribution to the oxidation state of the uranium atom made by that bond, the total of all the s values gives the oxidation state. Ro and B are constants which have been worked out by looking at lots of crystal lattices. So the parameters are derived from experimental results. Cadmium
Regarding these edits,
Just as I suspected, simply providing the fully source-supported facts which directly imply that UO3(g) is a combustion product results in just as much vandalistic deletionism as the fact which follows from them. The true color of censorship has never been so obvious. -- James S. 15:40, 10 April 2006 (UTC)
I have serious doubts about Image:UO3.jpg, the image that is continually being re-inserted by James to illustrate structure of the UO3 molecule in the gas phase. Caption: "Diagram of a uranyl oxide molecule. The formation of two short U=O bonds in the uranyl ion prevents the closer approach of the third oxygen " James has kindly provided the context here.
The paragraph the image is taken from talks about structure and bonding in UO22+, the uranyl cation.
Anyone got any thoughts on the suitability? If unsuitable, please remove! Dr Zak 19:09, 10 April 2006 (UTC)
I would vote for the removal of the pencil like drawing that you are talking about, I have read the whole of the source which James cited (Cotton) and it is not stating that it is the gas phase strucutre. Cadmium
I would concur that the diagram has nothing to do with gases UO3. Olin 23:22, 10 April 2006 (UTC)
Why?!? If it's a uranyl ion, what is the third oxygen doing in it? -- James S. 05:44, 11 April 2006 (UTC)
The third oxygen is a place holder for any ion trying to get close to the uranium, this is described by cotton.-- Stone 07:56, 11 April 2006 (UTC)
And we must not forget that the uranyl cation is most frequently encountered in aqueous solutions, where oxygen (from water) would be a ligand. Dr Zak 14:05, 11 April 2006 (UTC)
Quote from above:Do you drink coffee, or tea? Have you noticed that steam stays in the air as a vapor before it condenses? Why should it?!? Steam has missleading use. Vapor sometimes too. Gas or gas phase are the only with clear use. The vapor of water is a gas, steam should also consist of nothing than free molecules. But it is used as steam which you can see as white cloude,than it is no vapor or steam anymore but fine droplets of water in air. Two phase system which has already the condensation done. Vapor above a tee cup forms a cloude or fog or what ever you would call it. Drink a cup of tee at -20°C and you would see that all the water formes small dropps which freeze. The same will be in the case of Uraniumtrioxide. So you have small particles no vapor, gas or steam anymore. -- Stone 07:56, 11 April 2006 (UTC)
The equilibrium arrow doesn't come up right on my computer. I use:
⇌
which is a unicode thingy. I'll put it in. I'm glad we're treating two equations that are the microscopic reverse of each other as an equilibrium, since that is appropriate. Olin 15:07, 11 April 2006 (UTC)
⇌ looks like a small square on my one.-- Stone 20:04, 11 April 2006 (UTC)
Volatile is defined as "Evaporating readily at normal temperatures and pressures." or "That can be readily vaporized." [5] A few mbar of pressure high temperatures does not qualify as volatile, in my book, so I'd like to see if others agree thw word volatile should be stricken from the page. (Also, volatility is an innate property of a substance. "Volatile by oxidation" seems incorrect to me.) Olin 15:42, 12 April 2006 (UTC)
It's not my term, it's Alexander (2005)'s; in particular, Table 6 from which the figures were taken, is entitled "Total volatility...." How about "is volatilized in air"? -- James S. 18:06, 12 April 2006 (UTC)
You can have high volatility or low volatity, but only a compound with high volatility can be described with volatile the adjective. Volatize, the verb, does mean go to a gas, but still does not implay that a compound is volatile. Olin 18:58, 12 April 2006 (UTC)
We are discussing the second paragraph of the introduction, the one that begins At temperatures below the burning temperature of uranium in air .., right? Well, that whole section is a collection of non-sequiturs and what information is in there should go elsewhere. To elaborate:
Comments are appreciated. I would like to drop the paragraph altogether, for the reasons stated above. Dr Zak 19:42, 12 April 2006 (UTC)
I was more focussed the word "volatile"; I just don't think it's an accurate term. "Appreciable" or "nonnegligible vapor pressure at high temperatures" I can deal with, just not volatile. I do appreciate your comments about enthalpy (see the discussion above). Olin 22:55, 12 April 2006 (UTC)
The lithium salts sold have the same problem (most of it ends up in hydrogenbombs). Also the carbon from organic sources differ from that of inorganic sources. Is the effect big enough to mention in the table?-- Stone 06:48, 13 April 2006 (UTC)
(Gabelnick, Reedy, Chasanov, 1970) they published a lot 1970-1973 I think its from 1972 or 1973.-- Stone 11:58, 13 April 2006 (UTC)
Gabelnic SD, Reedy GT, Chasanov MG (1974). "Infrared-Spectra and Structure of some Matrix-Isolated Lanthanide and Actinide Oxides". Journal Chemical Physics. 60: 1167–1171.{{
cite journal}}
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link)
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link){{
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link)-- Stone 16:51, 13 April 2006 (UTC)
It's paper 2 in the series. My mistake. The citation in the References section is correct. Dr Zak 17:42, 13 April 2006 (UTC)
The introduction states that
Further down it says that
That sounds really inconsistent. If there is only one report stating that the compound is present then the text should read "most have suggested that UO3 is not a combustion product". Also, what exactly does that 1978 report say exactly about the composition of the oxide species that result from uranium combustion? What are the missing 25 %? When UO3 is not present (or present only in trace amounts) I do question the value of either statement in an article on uranium trioxide. The more suitable place is the article on uranium. Dr Zak 17:10, 13 April 2006 (UTC)
Hah. That UO2 makes up the rest of the dust from DU firings is what one's chemical intuition tells one and what Le Châtelier's principle predicts. At higher temperatures endothermic processes (e.g. oxygen loss) are favored. Gmelin mentions the fact in passing, here where it states that "U3O8 shows in its equilibrium state a noticeable oxygen deficiency already at 500 to 700 °C, which persists even after slow cooling in air". (Emphasis mine.) If no great amount of UO3 is formed during uranium combustion then it shouldn't be mentioned. Also, if U3O8 is more soluble than UO2 it would be taken up by cells preferentially, and don't forget that in the presence of water and air the uranyl ion is very stable. The report that you cite does not mention gas at all, only very fine particulate matter that enters deep into the lungs.
Nothing of what you cite supports the notion that UO3 is formted in any mount during uranium combustion, and that's why the article on uranium trioxide should not mention it as a combustion product. Dr Zak 20:45, 13 April 2006 (UTC)
I just browsed through the Salbu paper. It gives as products from DU projectiles UO2, U3O8 and uranyl carbonate (presumably from weathering of freshly formed particles). Nowhere is Uranium trioxide conclusively detected. Dr Zak 21:00, 13 April 2006 (UTC)
In Fig. 4 in the Salbu paper the powder diffraction patterns of UO3 and of some DU dust particles are compared. Note how the distinctive peak near d=3.4 of UO3 is absent in the DU samples. Salbu notes that herself, saying "the fit to UO3 ... data suffers from uncertainties". Also note the conclusions, where only U2O5 and uranyl salts are mentioned, not UO3. Dr Zak 14:18, 14 April 2006 (UTC)
The experimental section gives the spectra which is less specific than the conclusion!-- Stone 18:22, 14 April 2006 (UTC)
To answer your questions:
The XANES spectra aren't really diagnostic here - they at most tell the oxidation state and the interpretation is often doubtful. My very respected thesis advisor has described the method as "occupational therapy for physicists". On the other hand, the powder diffraction pattern of a compound is really diagnostic and powder patterns are excellent for fingerprinting. If a compound is present is will show ALL lines, all of them. If just one is missing and the rest fits the compound is not there. So the data in the Selbu paper do not support the assertion that UO3 is present in the combustion products.
Please stop sidetracking the issue. If you want uranium combustion mentioned in the article on UO3 give reliable sources that support the assertion that UO3 is a combustion product. Otherwise it has to go per WP:V. Dr Zak 19:22, 14 April 2006 (UTC)
SALBU:In a few particles, U showed a pattern similar to U2O5 (Fig. 4b), while most of the investigated particles originated from the fire could be attributed to solid uranyl compounds (e.g., UO2(CO3)), although the fit to UO3 literature XRD data suffers from uncertainties (Fig. 4c). Makes clear what you can think of the clear and undoubted finding of uranium trioxide. The author is at best not sure at worst wrong.-- Stone 22:35, 14 April 2006 (UTC)
WHERE IS UO3 IN THE COMBUSTION? I CANT FIND IT!!!!!!!!!!!!!!!-- Stone 22:35, 14 April 2006 (UTC)
Featuring a picture of the infamous T-shaped UO3 highlights a species that is at best of controversial and more likely simply unimportant. Otherwise, should we be depicting the structures of all species generated by vaporization of solid oxides, solid halides, solid sulfides.... In other words, depicting such a species violates the NPOV in a scientific sense, since it suggests significance where there is none. One solution would be to create a "gaseous UO3" article that could become the locus for the controversy and allow those that just want to understand this poor ole oxide to discuss its solid-state properties. Smokefoot 22:17, 18 April 2006 (UTC)
I recently sent the message below to Dr. Carl Alexander, who has been active in uranium physical chemistry for almost half a century, and is a famous scientist in other fields, participating in the Voyager space probe program and currently working on missile defense systems. He replied thusly:
-------- Forwarded Message -------- Subject: RE: uranium combustion produces how much UO3(g)? Date: Thu, 20 Apr 2006 16:31:15 -0400 From: Alexander, Carl A (alexandc at BATTELLE dot ORG) To: James Salsman (james at bovik dot org) I would expect that gaseous UO3 would be the major product of such “burning” in air. I consulted and reviewed Wendell Wilson’s paper prior to publication so I am familiar with it although I haven’t seen it in a good many years. I don’t know the health hazard of gaseous UO3 but chemically it behaves a lot like WO3 and WO3 is certainly a bad actor. Gaseous UO3 is quite stable and you are correct that upon condensing it would likely become U3O8. -----Original Message----- From: James Salsman Sent: Thursday, April 20, 2006 4:11 PM To: Alexander, Carl A Subject: uranium combustion produces how much UO3(g)? Dear Dr. Alexander: Thank you for publishing your paper, "Volatilization of urania under strongly oxidizing conditions," which I recently read with great interest. I have been trying to determine the amount of UO3(g) produced from combustion of uranium. I have recently been corresponding with the famous coordination chemist Prof. Simon Cotton, who suggested that I contact you with my question. Depleted uranium munitions such as those used for 20-30 mm and larger antitank ordnance are incendiary due to the pyrophoric nature of uranium. More than 30% of such bullets' uranium metal burns in air when they are fired against hard targets. It seems that the burning temperature should usually be above 2500 Kelvin, because the bullets are described as fragmenting into a spray of tiny particles as they pass through armor. (Mouradian and Baker (1963) "Burning Temperatures of Uranium and Zirconium in Air," Nuclear Science and Engineering, vol. 15, pp. 388-394.) Inhalation of uranium combustion fumes is suspected in major illnesses reported in veterans and civilians of the February, 1991 Gulf War. However, none of the people responsible for determining the health hazards has yet reported measurements of the gas vapors produced, only the particulate aerosol fumes, which are described as 25% UO2 and 75% U3O8 (Gilchrist R.L., et al. (1979) "Characterization of Airborne Uranium from Test Firings of XM774 Ammunition," Technical report no. PNL-2944 Richland, WA: Battelle Pacific Northwest Laboratory.) Based on the thermodynamic formation energy data I have been able to find (H. Wanner and I. Forest, eds. (2004) Chemical Thermodynamics of Uranium (Paris: OECD and French Nuclear Energy Agency) http://www.nea.fr/html/dbtdb/pubs/uranium.pdf -- see table V.4 on p. 98) it seems like production of UO3 would be much more likely than UO2 or U3O8. Moreover, condensation and subsequent decomposition of UO3(g) can explain the U3O8(s) product: see Wilson, W.B. (1961) "High-Pressure High-Temperature Investigation of the Uranium-Oxygen System," Journal of Inorganic Nuclear Chemistry, vol. 19, pp. 212-222, at the bottom of p. 213. If there are substantial amounts of UO3(g) produced in uranium fires, that could explain discrepancies in both troop exposure patterns and the solubility and resulting pharmokinetics of those exposed. Most people have been assuming that only the particulate aerosols present any exposure risk. But those settle out of the atmosphere much more quickly than gas, which is absorbed immediately if inhaled in contrast to the great length of time which it takes for UO2 and U3O8 particles to dissolve in the lungs. Urine tests intended to determine exposure which measure the ratio of uranium 238 and 235 isotopes assume that only particulate aerosols and not quickly absorbed and dissolving gas have been encountered. Those urine tests have been negative for exposure in patients who have the symptoms of uranyl poisoning. Can you please help shed any light on the amount of UO3(g) produced when uranium burns in air? Thank you. Sincerely, James Salsman
So, is it fair to say that "Uranium chemist Dr. Carl Alexander expects that gaseous UO3 would be the major product of uranium combustion in air"? -- James S. 16:47, 22 April 2006 (UTC)
It's a genuinely irrelevant statement. Everyone knows that U3O8(s) is in equilibrium with UO3(g). If you wish to use this to back up your pet theory of "UO3(g) from DU ammo hangs around and causes ill health" you would have to find something that supports that assertion. Dr Zak 03:02, 23 April 2006 (UTC)
Also note that Dr Alexander doesn't say a word about UO3 gas in the atmosphere in his reply. I guess he is just being polite. Dr Zak 03:04, 23 April 2006 (UTC)
POV dispute templates should not be removed unless both sides of the dispute agree that it is resolved. -- James S. 16:31, 27 April 2006 (UTC)
What kind of "extrapolation" is Nrcprm2026 being accused of here? The unreverted portion of the article already supports a T-shaped gas molecule. The other statements about depleted uranium weapons and gas from them are in the sources, not extrapolated from them. Why are people so sensitive about this issue? 12.178.40.29 20:51, 29 April 2006 (UTC)
This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 | Archive 2 | Archive 3 | Archive 4 |
Wilson and Ackerman never state any combustion products because they have done no combustion. So citing them for combustion is not OK. The Ackerman is only researching Oxides in general and the transformation. They state that there is no UO3 vapor present due to the calculations mentioned above. Sublimation from UO3 nor from U3O8 will ever occure at temperatures below 500°C which is OK with the calculations for the partial pressur of UO3.
You said someone should claim Ackemann wrong! He is right! He does chemical transport reaction from U3O8 nothing more and nothing less. Wilson is also right for Uraniumoxide interconversion. But they all give low vapour pressure for the oxide.
The condensation of the product is described by the gas law and the mass law. The calculationes done from me and others indicate that at standart conditions no UO3 gas is present. So why mention it at all. This is the poinz of the whole thing molecular UO3 is not woth mentioning! Because the vapour pressure of it is so close to zero that even if you assume its toxic nobody will ever take up more than a few molecules. So if you state that condensation is nearly 100% with only a few molecules in gasphase the whole UO3 mythe (flying around for weeks and gasous UO3 major product of combustion) can go!-- Stone 10:05, 29 March 2006 (UTC)
There is no statement that U03 is formed as main combustion product. Ackerman, Willson, Chatillon, Nakajma, Capone, Capone, Arai, Guido all start from different oxides and so the sublimation or transport reaction mentioned for the Ackermann paper fit to the problem and again we get nothing else as no UO3 vapor present due to the calculations mentioned above. Sublimation from UO3 nor from U3O8 will ever occure at temperatures below 500°C which is OK.
To give back the compliment you made: The rest is shown as object fraud, because your plasma burning uranium oxide is a nice try but the exact paper giving the plasma burning experiment of uranium and the composition of the gas phase is no where given. So who is doing the object fraud?
Back to the point:To give back the compliment you made: The rest is shown as object fraud, because your plasma burning uranium oxide is a nice try but the exact paper giving the plasma burning experiment of uranium and the composition of the gas phase is no where given.-- Stone 09:04, 29 March 2006 (UTC)
Another point why should be the most exothermic product be the one favoured at high temperatures? My chemistry knowledge says: high temperatures favour the less exothermic or endothermic reactions. Example: Burning coal: (Boudouard-Equilibrium)
400°C 99/1 600°C 77/23 800°C 10/90 1000°C 1/99
With this numbers UO would be the main compustionproduct.
So where is the literature indicating that this law of reactions is not true for the uranium oxides.
Stating that the uranium trioxide reacts different if it is created by plasma or sublimation simply shows a lack of chemical knowledge and is a point no chemist will ever accept.
Born Haber cycle is easy to understand and as simple as going up 2 flours with elevator and than 7 by the stairs or rocket up to the 12 flour and than 3 down with the fire ladder you end up in the same flour.
Everything else would give nosense. So first oxidising than sublimation than condensation makes no difference to sublimation of uranium than oxidation and than condensation.
The condensation from gas phase follows the rules of mass law. The air is oversaturated with uranium trioxide and the molecules have to follow the law and condense. This condensation is absolutely independent from which source the uranium trioxide molecules come from. How should the information stick to each molecule when to condense? -- Stone 09:29, 28 March 2006 (UTC)
Note: Please sign your comments with --~~~~ or at least four tildes. -- James S. 03:16, 29 March 2006 (UTC)
The point is and will always be why should a molecule with a low vapour pressure be a gas at normal conditions? A source for a example of this kind of behaviour would be good-- Stone
The micro particles flying around nobody will deny, the caesium-137 or so from the spain steel factory and the atomic tests is also flying around, but as particles or condensed to dust particles.
The dust particles go into the lung if they have certain diamater, this is shown in many studies. Germany has problems with microparticle dust from diesel motors. Studies show that this particles and up in the lung.-- Stone 07:04, 29 March 2006 (UTC)
Problem finding UO3 infrequently ignored in Gmelin 8 1977 Uranium C1 page 98 can you state if this is the right page number?-- Stone 07:13, 29 March 2006 (UTC)
Lets start wit the equation it self: can be found in [1]
log p= (((1.821 ± 0.075)· 104)/T) + 6.84 ± 0.58 log p= (((1.856 ± 0.016)· 104)/T) + 6.928 ± 0.103
I choose the first equation because it gives the higher pressure for UO3 gas.
log p= (((1.821 ± 0.075)· 104)/T) + 6.84 ± 0.58
Lets state 300K as the temperature (26°C or so)
putting in the numbers gives:
log p = -53.86
put both sides in the power over ten (native speaker needed)
p = 10-53.86 atm
p = 1.38 · 10-54 atm
convert from atm to Pa (1 atm = 101325 Pa)
p = 1.3985 · 10-49 Pa (N/m2)
Assuming that the laws of ideal gas are good for this problem
(which they are not, because the the condensation and the interaction between the molecules give even lower pressure for real gas at lower temperature than expected by the ideal gas euqaution)
p V= n R T
n = (p · V) / (R · T)
n =(1.3985 · 10-49 N/m2 · 1 m3)/ (8.314472 J · K-1 · mol-1 · 300 K)
n = 5.57 · 10-53 mol
so this is the number of mol per cubic meter of uranium trioxide.
1 mol = 6.023 · 1023 particles
So to get the number of particles in one cubic meter simpl multipie the numbers.
6.023 · 1023 5.57 · 10-53 = 3.35 · 10-29 particle per m3
Other way to point this numer is you need 2.98 · 1028 m3 to find on single atom of UO3.
Volume of earth 1.0832×1012 km3 = 1.0832×1021 m3 so even if the whole earth would be atmosphere there would be no molecule founnd in it. 600 times earth volume and you find your UO3.
The equations are right and the condensation follows this patter. Where am I wrong? This leads to no molecules in the gas phase after cooling at all.-- Stone 10:32, 29 March 2006 (UTC)
Does Cotton give UO3 or simnply uranyl than it has to go!-- Stone 11:10, 29 March 2006 (UTC)
Lets sat it the way it is:
Burning DU gives U3O8 UO3 UO2 in changing quantities. (Acording to differt literature) The condensed particle from this are small and do not settle qickly. The elevated radiation from UK during GW2 shows this clearly. Small particles get into the lung and due tue the fact that Uranyl compunds like UO3 dissolve quicker than U3O8 the toxicity of them is severe. This is absolutly OK.
My oppinion is, that DU is chemical warfare and only because its cheper than tungsten to poisen Irak and Yugoslavia with it is crimainal. The other nations use tungsten for ammunition and they know why! Is DU ammunition used in traing grounds in the US? I think they would not dare to do so, because theay get lawyers crawling around everywhere. -- Stone 11:27, 29 March 2006 (UTC)
The only thing to do is to get the first sentence to a state which makes clear that both cited references do not do the research indicated in the sentence bevor.
Which is critical in my point of few.-- Stone 11:33, 29 March 2006 (UTC)
The transport reaction was OK I think. This is a example for UO3 molecules and could stay. The matrix experiments with single UO3 molecules where also resonable. -- Stone 16:51, 29 March 2006 (UTC)
The references section is almost as long as the article itself, and a fair number of the articles cited there seem not to be used. 129.215.195.81 14:57, 30 March 2006 (UTC)
Given the recent phenomina of fresh anons reverting away source-supported statements, and apparently planning to delete sources, above, as their only edits here, I propose partial protection of the recent dispute-tagged version for a short while. Are there any objections? -- James S. 22:55, 30 March 2006 (UTC)
Does anyone care to defend this? -- James S. 22:32, 31 March 2006 (UTC)
From a realy good article about: Volatilization of urania under strongly oxidizing conditions Journal of Nuclear Materials 346 (2005) 312–318 C.A. Alexander
If the oxygen partial pressure is held constant and the temperature raised, then the composition will shift to a lower value of the O/U ratio. Since the higher oxidation state at a specific temperature will have a more negative free energy,
This states higher temperature makes substances with more free energy unstable! -- Stone 08:07, 31 March 2006 (UTC)
Ther should be headlines for
like in most other articles. This article is and will be a mess! I will try to build up a new one User:Stone/Uraniumtrioxide leaving out
Which can be but in from somebody else!-- Stone 08:18, 31 March 2006 (UTC)
is more accurate, taller, has many fewer characters than the graphic, and so it takes less time to load. -- James S. 19:51, 31 March 2006 (UTC)
Urine tests for isotope ratios are worthless, because the isotopes translocate at different rates. Anything less than chromosome analysis after one year is worthless. -- James S. 19:58, 31 March 2006 (UTC)
{{ fact}}?? The isotope effect for U-235 and U-238 is minimal, this isn't hydrogen and deuterium we are talking about. 82.41.26.244 20:25, 31 March 2006 (UTC)
There is an currently edit war going on if the gas phase structure should be placed above or below the solid-state structure. We also now have a pretty graphic of the molecule in the gas phase.
My take on the matter:
I have examined the work cited by James S. which was by C. Busby. After reading it I have come to the conclusion that it is less trustworthy than papers printed in more traditional chemical, physics or biological journals.
The paper is Busby, C. and S. Morgan (2006) "Did the use of Uranium weapons in Gulf War 2 result in contamination of Europe?" European Biology and Bioelectromagnetics, 1(5), 650-668.
Why would the molecule be T shaped ? I know that a matrix isolation study has been cited, but in a condensed phase packing effects could distort the molecule from the shape found in the gas phase. Valence Shell Electron Pair Repulsion theory ( VSEPR) which is one of the best predictive tools for simple molecules would predict a C3 trigonal shape like that of BF3. Cadmium 17:27, 1 April 2006 (UTC)
Filling the article up with solid polymorph forms, while removing the source-supported statements about gas production is such obvious bias. This bias is made all the more obvious with the lung solubility reference to "elimination" -- a pharmokinetic term meaning excretion, urination, or perspiration, from the Morrow (1972) reference to lung fluid solubility -- certainly a much larger, plainly factual error than removing the reference to the controversial Busby article. It is so sad that so many people want to participate in supressing information about the gas phase. Why not just remove all references to water vapor from articles involving boiling water? -- James S. 20:52, 2 April 2006 (UTC)
And another thing, Cadmium, why are your oxygen diameters so tiny? Your diagrams are seriously misleading. -- James S. 20:58, 2 April 2006 (UTC)
Cadmium: I have these further questions about your recent reversion which is just a copy of others' reverts:
The Uranium trioxid GAS also found its way into the uranium page! As combustion product!-- Stone 09:11, 5 April 2006 (UTC)
I found no indication that there is no source for Uranium trioxide as primary combustion product. So I will delet the unsourced citations.-- Stone 13:49, 5 April 2006 (UTC)
I think that each polymorph does need its own subsection, I intend to add more on each one. For some forms more than one diagram is needed. James has compressed the solid state chemistry into too small a space for it to be clear. I agree that under some comditions that UO3 gas can exist, but the solid state is more important as the vast majoirty of the chemistry of UO3 is of the solid. Cadmium
As there is only the combination of wilsom and ackermann this is simply not enough to claim combustion product. The found combustion product in kuwait tank fire is probably UO3 which is als not enough to claim UO3 combustion product.-- Stone 08:10, 6 April 2006 (UTC)
Ther is no combustion mentioned! Cotton states uranyl compounds nothing else! If I state they rise from the quantum vacuum, this would also be possibel but also unreferenced!-- Stone 07:31, 7 April 2006 (UTC)
Are you afraide to have a opponent with high level experience of Chemical warfare? The G. Schrader working group was always my favorit for phosphor chemistry and the Labwork of Haber and Grignard on sulfide chemistry are also a highlight of french and german chemistry!-- Stone 08:02, 11 April 2006 (UTC)
Let's also mention that the vapor pressure of UO3 at 980 °C is 10 nanobars or to. Someone who breathes in the gas has other things to worry about that gaseous combustion products of uranium.
To mention pot in a long section is a little bit more than necesarry. The whole article will benedit from som tidy up.-- Stone 08:10, 6 April 2006 (UTC)
After redoing all the literature and adding use and Production I think the structures of the delta and the beta form could have their place on the supplementary page? These pictures are good, but they take a lot of space and load.-- Stone 10:29, 6 April 2006 (UTC)
The links to the scanned and downloaded pdfs of www.bovik.org have a questionable legal status here in Europe, and I do not know what the rights owners would think if they find them linked to this article. We know them an most of us red them so why keep them on the front page? Put them to the talk page or so than anybody interested in the little uraniumoxide controversy can download them from there.-- Stone
If you realy want I write a letter to elsevier, that you use their articles on this page. -- Stone 07:29, 7 April 2006 (UTC)
Still have the feeling that the structures take mor place than necesarry-- Stone 07:33, 7 April 2006 (UTC)
I realize this is a big edit war (in which I have no desire to get involved), but I condensed the production section and removed the other two times it is brought up.
Here are my suggestions for the article. It would be preferable for this to follow the WikiChemicals template, but if I were to ignore that for a second:
Right now this article is a big mess. Olin
However, having said that, I don't understand Cadmium's latest structure calculations, so I'm going to move them here to the talk page. -- James S. 07:58, 9 April 2006 (UTC)
It is possible by bond valence calculations [2] it is possible to estimate how great a contribution a given oxygen atom is making to the assumed valence of uranium. Zachariasen, J. Less Common Met., 1978, 62, 1-7. Lists the parameters to allow such calculations to be done for many of the actinides.
The formula to use is
For uranium binding to oxygen the constants Ro and B are tabulated in the table below. For each oxidation state use the parameters from the table shown below.
Oxidation state | Ro | B |
---|---|---|
U(VI) | 2.08Å | 0.35 |
U(V) | 2.10Å | 0.35 |
U(IV) | 2.13Å | 0.35 |
It is possible to do these calculations on a scrap of paper (old skool method) or software which does it can be obtained free of charge. [3] [4]
Using a 6Å x 6Å x 6Å box with the uranium atom in the centre the bond valence calculation was performed for both U1 and U2 in the delta phase of uranium trioxide. It was found using the parameters for U(VI) that the calculated oxidation states for U1 and U2 are 6.78 and 6.13.
R is the distance from the oxygen to the uranium atom s is the contribution to the oxidation state of the uranium atom made by that bond, the total of all the s values gives the oxidation state. Ro and B are constants which have been worked out by looking at lots of crystal lattices. So the parameters are derived from experimental results. Cadmium
Regarding these edits,
Just as I suspected, simply providing the fully source-supported facts which directly imply that UO3(g) is a combustion product results in just as much vandalistic deletionism as the fact which follows from them. The true color of censorship has never been so obvious. -- James S. 15:40, 10 April 2006 (UTC)
I have serious doubts about Image:UO3.jpg, the image that is continually being re-inserted by James to illustrate structure of the UO3 molecule in the gas phase. Caption: "Diagram of a uranyl oxide molecule. The formation of two short U=O bonds in the uranyl ion prevents the closer approach of the third oxygen " James has kindly provided the context here.
The paragraph the image is taken from talks about structure and bonding in UO22+, the uranyl cation.
Anyone got any thoughts on the suitability? If unsuitable, please remove! Dr Zak 19:09, 10 April 2006 (UTC)
I would vote for the removal of the pencil like drawing that you are talking about, I have read the whole of the source which James cited (Cotton) and it is not stating that it is the gas phase strucutre. Cadmium
I would concur that the diagram has nothing to do with gases UO3. Olin 23:22, 10 April 2006 (UTC)
Why?!? If it's a uranyl ion, what is the third oxygen doing in it? -- James S. 05:44, 11 April 2006 (UTC)
The third oxygen is a place holder for any ion trying to get close to the uranium, this is described by cotton.-- Stone 07:56, 11 April 2006 (UTC)
And we must not forget that the uranyl cation is most frequently encountered in aqueous solutions, where oxygen (from water) would be a ligand. Dr Zak 14:05, 11 April 2006 (UTC)
Quote from above:Do you drink coffee, or tea? Have you noticed that steam stays in the air as a vapor before it condenses? Why should it?!? Steam has missleading use. Vapor sometimes too. Gas or gas phase are the only with clear use. The vapor of water is a gas, steam should also consist of nothing than free molecules. But it is used as steam which you can see as white cloude,than it is no vapor or steam anymore but fine droplets of water in air. Two phase system which has already the condensation done. Vapor above a tee cup forms a cloude or fog or what ever you would call it. Drink a cup of tee at -20°C and you would see that all the water formes small dropps which freeze. The same will be in the case of Uraniumtrioxide. So you have small particles no vapor, gas or steam anymore. -- Stone 07:56, 11 April 2006 (UTC)
The equilibrium arrow doesn't come up right on my computer. I use:
⇌
which is a unicode thingy. I'll put it in. I'm glad we're treating two equations that are the microscopic reverse of each other as an equilibrium, since that is appropriate. Olin 15:07, 11 April 2006 (UTC)
⇌ looks like a small square on my one.-- Stone 20:04, 11 April 2006 (UTC)
Volatile is defined as "Evaporating readily at normal temperatures and pressures." or "That can be readily vaporized." [5] A few mbar of pressure high temperatures does not qualify as volatile, in my book, so I'd like to see if others agree thw word volatile should be stricken from the page. (Also, volatility is an innate property of a substance. "Volatile by oxidation" seems incorrect to me.) Olin 15:42, 12 April 2006 (UTC)
It's not my term, it's Alexander (2005)'s; in particular, Table 6 from which the figures were taken, is entitled "Total volatility...." How about "is volatilized in air"? -- James S. 18:06, 12 April 2006 (UTC)
You can have high volatility or low volatity, but only a compound with high volatility can be described with volatile the adjective. Volatize, the verb, does mean go to a gas, but still does not implay that a compound is volatile. Olin 18:58, 12 April 2006 (UTC)
We are discussing the second paragraph of the introduction, the one that begins At temperatures below the burning temperature of uranium in air .., right? Well, that whole section is a collection of non-sequiturs and what information is in there should go elsewhere. To elaborate:
Comments are appreciated. I would like to drop the paragraph altogether, for the reasons stated above. Dr Zak 19:42, 12 April 2006 (UTC)
I was more focussed the word "volatile"; I just don't think it's an accurate term. "Appreciable" or "nonnegligible vapor pressure at high temperatures" I can deal with, just not volatile. I do appreciate your comments about enthalpy (see the discussion above). Olin 22:55, 12 April 2006 (UTC)
The lithium salts sold have the same problem (most of it ends up in hydrogenbombs). Also the carbon from organic sources differ from that of inorganic sources. Is the effect big enough to mention in the table?-- Stone 06:48, 13 April 2006 (UTC)
(Gabelnick, Reedy, Chasanov, 1970) they published a lot 1970-1973 I think its from 1972 or 1973.-- Stone 11:58, 13 April 2006 (UTC)
Gabelnic SD, Reedy GT, Chasanov MG (1974). "Infrared-Spectra and Structure of some Matrix-Isolated Lanthanide and Actinide Oxides". Journal Chemical Physics. 60: 1167–1171.{{
cite journal}}
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link)
{{
cite journal}}
: CS1 maint: multiple names: authors list (
link){{
cite journal}}
: CS1 maint: multiple names: authors list (
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link)-- Stone 16:51, 13 April 2006 (UTC)
It's paper 2 in the series. My mistake. The citation in the References section is correct. Dr Zak 17:42, 13 April 2006 (UTC)
The introduction states that
Further down it says that
That sounds really inconsistent. If there is only one report stating that the compound is present then the text should read "most have suggested that UO3 is not a combustion product". Also, what exactly does that 1978 report say exactly about the composition of the oxide species that result from uranium combustion? What are the missing 25 %? When UO3 is not present (or present only in trace amounts) I do question the value of either statement in an article on uranium trioxide. The more suitable place is the article on uranium. Dr Zak 17:10, 13 April 2006 (UTC)
Hah. That UO2 makes up the rest of the dust from DU firings is what one's chemical intuition tells one and what Le Châtelier's principle predicts. At higher temperatures endothermic processes (e.g. oxygen loss) are favored. Gmelin mentions the fact in passing, here where it states that "U3O8 shows in its equilibrium state a noticeable oxygen deficiency already at 500 to 700 °C, which persists even after slow cooling in air". (Emphasis mine.) If no great amount of UO3 is formed during uranium combustion then it shouldn't be mentioned. Also, if U3O8 is more soluble than UO2 it would be taken up by cells preferentially, and don't forget that in the presence of water and air the uranyl ion is very stable. The report that you cite does not mention gas at all, only very fine particulate matter that enters deep into the lungs.
Nothing of what you cite supports the notion that UO3 is formted in any mount during uranium combustion, and that's why the article on uranium trioxide should not mention it as a combustion product. Dr Zak 20:45, 13 April 2006 (UTC)
I just browsed through the Salbu paper. It gives as products from DU projectiles UO2, U3O8 and uranyl carbonate (presumably from weathering of freshly formed particles). Nowhere is Uranium trioxide conclusively detected. Dr Zak 21:00, 13 April 2006 (UTC)
In Fig. 4 in the Salbu paper the powder diffraction patterns of UO3 and of some DU dust particles are compared. Note how the distinctive peak near d=3.4 of UO3 is absent in the DU samples. Salbu notes that herself, saying "the fit to UO3 ... data suffers from uncertainties". Also note the conclusions, where only U2O5 and uranyl salts are mentioned, not UO3. Dr Zak 14:18, 14 April 2006 (UTC)
The experimental section gives the spectra which is less specific than the conclusion!-- Stone 18:22, 14 April 2006 (UTC)
To answer your questions:
The XANES spectra aren't really diagnostic here - they at most tell the oxidation state and the interpretation is often doubtful. My very respected thesis advisor has described the method as "occupational therapy for physicists". On the other hand, the powder diffraction pattern of a compound is really diagnostic and powder patterns are excellent for fingerprinting. If a compound is present is will show ALL lines, all of them. If just one is missing and the rest fits the compound is not there. So the data in the Selbu paper do not support the assertion that UO3 is present in the combustion products.
Please stop sidetracking the issue. If you want uranium combustion mentioned in the article on UO3 give reliable sources that support the assertion that UO3 is a combustion product. Otherwise it has to go per WP:V. Dr Zak 19:22, 14 April 2006 (UTC)
SALBU:In a few particles, U showed a pattern similar to U2O5 (Fig. 4b), while most of the investigated particles originated from the fire could be attributed to solid uranyl compounds (e.g., UO2(CO3)), although the fit to UO3 literature XRD data suffers from uncertainties (Fig. 4c). Makes clear what you can think of the clear and undoubted finding of uranium trioxide. The author is at best not sure at worst wrong.-- Stone 22:35, 14 April 2006 (UTC)
WHERE IS UO3 IN THE COMBUSTION? I CANT FIND IT!!!!!!!!!!!!!!!-- Stone 22:35, 14 April 2006 (UTC)
Featuring a picture of the infamous T-shaped UO3 highlights a species that is at best of controversial and more likely simply unimportant. Otherwise, should we be depicting the structures of all species generated by vaporization of solid oxides, solid halides, solid sulfides.... In other words, depicting such a species violates the NPOV in a scientific sense, since it suggests significance where there is none. One solution would be to create a "gaseous UO3" article that could become the locus for the controversy and allow those that just want to understand this poor ole oxide to discuss its solid-state properties. Smokefoot 22:17, 18 April 2006 (UTC)
I recently sent the message below to Dr. Carl Alexander, who has been active in uranium physical chemistry for almost half a century, and is a famous scientist in other fields, participating in the Voyager space probe program and currently working on missile defense systems. He replied thusly:
-------- Forwarded Message -------- Subject: RE: uranium combustion produces how much UO3(g)? Date: Thu, 20 Apr 2006 16:31:15 -0400 From: Alexander, Carl A (alexandc at BATTELLE dot ORG) To: James Salsman (james at bovik dot org) I would expect that gaseous UO3 would be the major product of such “burning” in air. I consulted and reviewed Wendell Wilson’s paper prior to publication so I am familiar with it although I haven’t seen it in a good many years. I don’t know the health hazard of gaseous UO3 but chemically it behaves a lot like WO3 and WO3 is certainly a bad actor. Gaseous UO3 is quite stable and you are correct that upon condensing it would likely become U3O8. -----Original Message----- From: James Salsman Sent: Thursday, April 20, 2006 4:11 PM To: Alexander, Carl A Subject: uranium combustion produces how much UO3(g)? Dear Dr. Alexander: Thank you for publishing your paper, "Volatilization of urania under strongly oxidizing conditions," which I recently read with great interest. I have been trying to determine the amount of UO3(g) produced from combustion of uranium. I have recently been corresponding with the famous coordination chemist Prof. Simon Cotton, who suggested that I contact you with my question. Depleted uranium munitions such as those used for 20-30 mm and larger antitank ordnance are incendiary due to the pyrophoric nature of uranium. More than 30% of such bullets' uranium metal burns in air when they are fired against hard targets. It seems that the burning temperature should usually be above 2500 Kelvin, because the bullets are described as fragmenting into a spray of tiny particles as they pass through armor. (Mouradian and Baker (1963) "Burning Temperatures of Uranium and Zirconium in Air," Nuclear Science and Engineering, vol. 15, pp. 388-394.) Inhalation of uranium combustion fumes is suspected in major illnesses reported in veterans and civilians of the February, 1991 Gulf War. However, none of the people responsible for determining the health hazards has yet reported measurements of the gas vapors produced, only the particulate aerosol fumes, which are described as 25% UO2 and 75% U3O8 (Gilchrist R.L., et al. (1979) "Characterization of Airborne Uranium from Test Firings of XM774 Ammunition," Technical report no. PNL-2944 Richland, WA: Battelle Pacific Northwest Laboratory.) Based on the thermodynamic formation energy data I have been able to find (H. Wanner and I. Forest, eds. (2004) Chemical Thermodynamics of Uranium (Paris: OECD and French Nuclear Energy Agency) http://www.nea.fr/html/dbtdb/pubs/uranium.pdf -- see table V.4 on p. 98) it seems like production of UO3 would be much more likely than UO2 or U3O8. Moreover, condensation and subsequent decomposition of UO3(g) can explain the U3O8(s) product: see Wilson, W.B. (1961) "High-Pressure High-Temperature Investigation of the Uranium-Oxygen System," Journal of Inorganic Nuclear Chemistry, vol. 19, pp. 212-222, at the bottom of p. 213. If there are substantial amounts of UO3(g) produced in uranium fires, that could explain discrepancies in both troop exposure patterns and the solubility and resulting pharmokinetics of those exposed. Most people have been assuming that only the particulate aerosols present any exposure risk. But those settle out of the atmosphere much more quickly than gas, which is absorbed immediately if inhaled in contrast to the great length of time which it takes for UO2 and U3O8 particles to dissolve in the lungs. Urine tests intended to determine exposure which measure the ratio of uranium 238 and 235 isotopes assume that only particulate aerosols and not quickly absorbed and dissolving gas have been encountered. Those urine tests have been negative for exposure in patients who have the symptoms of uranyl poisoning. Can you please help shed any light on the amount of UO3(g) produced when uranium burns in air? Thank you. Sincerely, James Salsman
So, is it fair to say that "Uranium chemist Dr. Carl Alexander expects that gaseous UO3 would be the major product of uranium combustion in air"? -- James S. 16:47, 22 April 2006 (UTC)
It's a genuinely irrelevant statement. Everyone knows that U3O8(s) is in equilibrium with UO3(g). If you wish to use this to back up your pet theory of "UO3(g) from DU ammo hangs around and causes ill health" you would have to find something that supports that assertion. Dr Zak 03:02, 23 April 2006 (UTC)
Also note that Dr Alexander doesn't say a word about UO3 gas in the atmosphere in his reply. I guess he is just being polite. Dr Zak 03:04, 23 April 2006 (UTC)
POV dispute templates should not be removed unless both sides of the dispute agree that it is resolved. -- James S. 16:31, 27 April 2006 (UTC)
What kind of "extrapolation" is Nrcprm2026 being accused of here? The unreverted portion of the article already supports a T-shaped gas molecule. The other statements about depleted uranium weapons and gas from them are in the sources, not extrapolated from them. Why are people so sensitive about this issue? 12.178.40.29 20:51, 29 April 2006 (UTC)