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The article should follow the Article structure guidelines of the Wikipedia:WikiProject Elements. Also done in Berylium page wich is th combustion product of F1 race cars.--[[User:Stone|Stone]] 11:11, 5 April 2006 (UTC)
The article should follow the Article structure guidelines of the Wikipedia:WikiProject Elements. Also done in Berylium page wich is th combustion product of F1 race cars.--[[User:Stone|Stone]] 11:11, 5 April 2006 (UTC)

:I understand what Stone is implying here: he is saying the combustion products should not be so "high" in the article. I think the section is important, but since the oxides are under compounds anyway, the compounds section might be a more appropriate spot for that material. [[User:Olin|Olin]] 21:49, 5 April 2006 (UTC)

Revision as of 21:49, 5 April 2006

Article changed over to new WikiProject Elements format by contributors to /Temp and mav 11:18, 9 Jan 2004 (UTC). Elementbox converted 10:57, 17 July 2005 by Femto (previous revision was that of 02:00, 15 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.


Caution needs to be exercised in using the words fissile and fissionable.

U-238 is fissionable, and fast fission of U-238 delivers much of the power in three-stage fission-fusion-fission weapons. But it is not fissile, and contributes little to the power of a thermal or near-thermal power reactor (the PWR and BWR are not fully thermalised, owing to the competing need to reduce neutron losses).

U-235 and U-233 are fissile. Andrewa 17:01 20 Jun 2003 (UTC)


Shouldn't the atomic weight (somewhere around 210-250 or so) be mentioned in the article? Ilyanep 22:03, 2 Sep 2003 (UTC)

In the table now. --mav 11:18, 9 Jan 2004 (UTC)

Question: The text says "Because uranium has such a long radioactive half-life (4.47x109 years for U-238), the total amount of it on Earth stays almost the same." However, this isn't strictly true -- the half-life implies that there's only about half the amount of uranium left of what existed when the Earth was created. --Guan 19:38, 29 Nov 2004 (UTC)

Hmm, yeah, that doesn't make much sense, I don't think. I've removed it -- better to omit something like that than to have it be wrong, I think. If someone knows better, please re-insert it. --Fastfission 04:59, 10 Apr 2005 (UTC)

This article should probably link to the articles on radiomentirc dating since there are a few radiometric dating methods than measure uranium isotopes--nixie 01:23, 10 Apr 2005 (UTC)

I added a small line about it to the "applications" section. --Fastfission 04:59, 10 Apr 2005 (UTC)

anl.gov is down right now, so I can't check Fastfission's statement about the hazards of the decay products. However, U238 is an alpha emitter, the next two decay products are beta emitters, leaving U234. The alpha emitters are far more dangerous than beta's because alphas are typically very high energy, and for a given energy they are more damaging. U234 is an alpha, but the next decay product, Th230 has a half life of 80,000 years, so very little of it builds up in human timescales. As for U235, an alpha emitter, the next daughter is a beta emitter, and the next is Th 231 with a half life of 32,500 years, so it doesn't have time to build up. To summarize, the radiation of the parent uranium isotopes are far more hazardous than the daughters. pstudier 02:15, 2005 Apr 15 (UTC)

From ANL.gov:
Uranium is not considered a chemical carcinogen. A second concern is for uranium deposited in bone, which can lead to bone cancer as a result of the ionizing radiation associated with the radioactive decay products. Uranium has caused reproductive problems in laboratory animals and developmental problems in young animals, but it is not known if these problems exist for humans.
Additionally, the decay series of uranium-238 is not trivial; it is what is responsible for radon gas and its own hazardous daughter products. As I understand it. (I'm not trying to trump up its danger, I'm just trying to get it right). --Fastfission 16:21, 15 Apr 2005 (UTC)
What I tried to say is that in a time scale of less than a few thousand years, the radioactivity of the daughters is insignificant because they don't have time to build up. You won't get significant radon from a piece of uranium in our lifetime. pstudier 21:28, 2005 Apr 15 (UTC)
So how does that accord with the information from Argonne and the fact that significant amounts of radon gas are emitted by uranium deposits? --Fastfission 22:33, 15 Apr 2005 (UTC)
Simple: pure, refined uranium is no significant radiation hazard, because it needs time to decay into dangerous daughter products. Natural uranium exists in equilibrium with its daughter products, and therefore poses a slight, but still significant radiation hazard.
The Argonne information conflicts with what the Uranium Information Centre Ltd [1] and others have claimed. My guess is that it is only a minor hazard from the ionizing radiation of uranium. On the other hand, uranium deposits are generally much older than the few hundred thousand years it takes for the daughters to build up to equilibrium. Most obnoxious is radon because it is a gas that travels, and it deposits radioactive daughters Pb214 and Bi214 inside peoples lungs. Back before computer monitors were antistatic coated, one could wipe off the dust and detect Pb214 and the Bi214 with a Geiger counter, and watch it decay away. See Nuclear Electricity for a nice chart of the decay chains for U238 and U235. pstudier 22:58, 2005 Apr 15 (UTC)
So who do we go with? Argonne National Lab, or an organization which is funded by uranium miners and whose articles seem to be bent on portraying uranium as harmless? A google search for "uranium bone ionizing radiation site:.gov" seems to imply that there are quite a lot of US government sites out there which report that uranium deposits itself into bone and can be cancer causing.

From ANL.GOV Depleted Uranium, we find that 30mg of uranium will cause Potential irreversible adverse effects. The specific activity of natural uranium is 6.77E-7 Ci/gram. So this 30mg is about 20,000 pCi. From ANL.GOV Uranium, we find that the lifetime cancer risk for ingesting U238 is 7.5E-11 /pCi. I use U238 as the numbers are just a bit less for the other isotopes. So if we eat 30mg of uranium we will get sick but have a lifetime risk of cancer of 1.5E-6, or 1.5 in a million. I would say that the risk of getting cancer by ingesting uranium is insignificant compared to getting sick by chemical poisoning. pstudier 00:54, 2005 Apr 16 (UTC)

I agree completely with that, but I think stating forcefully that it is not a carcinogen is simply incorrect, whether or not it is a very potent one. I'm aware, of course, that nearly every substance is a carcinogen to some degree, but I believe I once read (I can look this up) that the FDA defines (or maybe just defined) a chemical as a carcinogenic risk if it would cause cancer in 1 out of a million people, so 1.5 would be well within that. Anyway though, I can look that up. I don't remember the exact specification or whether it was in the past tense or not. In any event, I am again not trying to overstate the radioactive dangers of uranium (and I'm aware it is part of a more contentious debate over DU) because it is clear to me anyway that its toxicity dangers are far more likely to have an effect (and, in the case of DU weapons or nuclear weapons, the intended death-causing mechanisms are going to be much more effective than this sort of thing!), but I don't want to under-state it either.--Fastfission 03:08, 16 Apr 2005 (UTC)
How about Uranium is a very weak carcinogen. Chemical toxicity, especially to the kidneys, is a greater health risk than radiological effects. Applies even more so to depleted uranium because it is about half as radioactive. pstudier 23:16, 2005 Apr 16 (UTC)

A leading encyclopedia has articles on the following four topics

  1. Uranium Processing
  2. Uranium Series
  3. Uranium-234-Uranium-238 Dating
  4. Uranium-Thorium-Lead Dating

It would be good if we can show we have the same coverage (by able to redirect this titles to pages containing the same sort of information. Any ideas? Pcb21| Pete 3 July 2005 10:08 (UTC)

Melting Point Discrepancy

The info box lists the melting point of uranium as 1405 kelvin or 2912 farenheight. These are rather different temperatures. Even if you try using the value given for kelvin as a celcius figure it's still off. Which one is correct? Icelight 20:10, July 14, 2005 (UTC)

[2] says 1405.3 K and 2070 F, I guess the fahrenheit one is incorrect. --kudz75 01:38, 15 July 2005 (UTC)[reply]

What's a "ton"?

What are the "tons" for U.S. production? I'd guess metric tons, but maybe short tons? Or even long tons, which until at least a few decades ago were used for some mining such as iron ore production in the U.S. Gene Nygaard 03:30, 5 August 2005 (UTC)[reply]

Cameco

I made a few corrections about the reference to Cameco Corporation. Cameco mines uranium in the Athabasca Basin, not the "Athabaska." In Saskatchewan, it has two operating uranium mines (Rabbit Lake and McArthur River), one mine in development (Cigar Lake), and one mill (Key Lake). jamin24601 07:24, 7 November 2005 (UTC)[reply]

1841?

What is the standard for "isolation" of a metal?

As a metal from ore, wouldn't it date to antiquated iron-age smelting, for early contact with, say, a 50% refined element -- 1500s? What is the chance that early ore-seekers would come upon rich enough deposits? Nrcprm2026 19:35, 22 December 2005 (UTC)[reply]

Isotopes

The last two paragraphs of this section look strange. The first is:

Given that the half life of 235U is considerably shorter than 238U, the "depleted" uranium is still significantly radioactive, as is the natural uranium after refining.

This reads as a non sequitur. The actual activity of DU will depend on how much 235U is present, and the relative activities of 235U and 238U. Is that what the original author was trying to say, or something else?

The last paragraph begins:

Another way to look at this is as follows: Pressurised Heavy Water Reactors (PHWR) use natural uranium (0.71% fissile material) [...]

This sounds like someone is trying to persuade the reader, or (worse) the author of the preceeding paragraph, as opposed to just laying down the facts.

I recommend they be removed, and perhaps the details on enrichment be left as a simple wikilink. mdf 20:03, 8 March 2006 (UTC)[reply]

Combustion products - refs

Please add full reference information for the sources given in this new section. Vsmith 14:29, 25 March 2006 (UTC)[reply]

The section was copied from Uranium trioxide which has full references; I have included it as the main article for the section. --James S. 14:54, 25 March 2006 (UTC)[reply]
Which, as the talk page shows, seems to be highly contested. Only James S. seems to be pushing this line. I don't know enough about the topic to know the state of the literature but the fact that it is one person against about three or four makes me very suspicious that it is original research, especially since James seems to be personally involved in trying to petition about these issues in his real life. --Fastfission 16:06, 25 March 2006 (UTC)[reply]
There are other editors supporting my efforts; the controversy was apparent long before I got here. I'm the only one who bothers to go to the library on a regular basis to check facts -- with which there are serious problems on both sides of the debate. Some people are far more anti-DU than I am, believing it is equivalent to the use of nuclear weapons. My edits, which are well-supported with sources from the peer-reviewed and scholarly medical and scientific literature, represent the truth as best as I can determine it. I admit that I am opposed to DU weapons, but I was not in 2004 before I started looking at the question. --James S. 19:46, 25 March 2006 (UTC)[reply]
I'm not getting into the dispute one way or another, I'm just pointing out that there is one, and that you seem to be the primary person pushing a particular approach, one clearly linked with a personal agenda, claiming to be pursuing the "truth" (rather than a reflection of the current literature, which is what Wikipedia aspires for itself), which raises my eyebrow a bit as the standard habit of POV-pushers. But I do not claim competency in the subject matter so I'm not arguing one way or another; just pointing out that I'm fairly suspicious. --Fastfission 19:58, 25 March 2006 (UTC)[reply]
The combustion products are verisitiel and strongly depend on the conditions. The main dispute on the UO3 page is not which comustion products occure, but which state they are in. Solid or vapour at standart conditions. --Stone 11:43, 27 March 2006 (UTC)[reply]

Question about the 236U half life

The article says that 236U is "very short lived", yet the half life listed for it is 23 million years. What is going on here? Sjakkalle (Check!) 14:52, 28 March 2006 (UTC)[reply]

Decorporation therapies

How about the top five? ... Decorporation therapies are already acknoledged by several authorities as essential for exposure victims, and the correct toxicological response to exposure to the highly-soluble uranyl-laden forms such as UO3(g) and to a lesser extent U3O8(s), is a notable aspect of health and safety concerns. --James S. 01:30, 1 April 2006 (UTC)[reply]

I'll start:

  1. 3,4,3-LIHOPO --James S. 05:30, 1 April 2006 (UTC)[reply]

Mitigation therapies

Is anyone interested in substances which decrease lipid oxidation by stimulating cellular production of enzymes such superoxide dismutase and catalase? --James S. 05:07, 1 April 2006 (UTC)[reply]

Spill cleanup

We need a list of the top five plants. [3] [4] [5] [6] [7] [8]

The bacteria (e.g. deinococcus radiodurans more) mutate so quickly I'm amazed that the plants can even hold on to their chlorophyll patterns, but apparently there are a few of them which are now very good at it. --James S. 20:01, 31 March 2006 (UTC)[reply]

How are spills cordoned off? --James S. 05:07, 1 April 2006 (UTC)[reply]

Largest Exporter

In spite of Australia's huge reserves, Canada remains the largest exporter of uranium ore with mines located in Athabasca basin in northern Saskatchewan. Cameco, the world’s largest, low-cost uranium producer accounting for 18% of the world’s uranium production, operates 3 mines in the area.

I believe that has to be updated now, in light of the deal signed between Australia and China, it (according to the news segment) makes Australia the worlds largest exporter, if i can find a news link that says this and outlines the %'s exported, i will update it, unless someone else can first--Nirvana- 07:20, 3 April 2006 (UTC)[reply]

Article structure guidelines

The article should follow the Article structure guidelines of the Wikipedia:WikiProject Elements. Also done in Berylium page wich is th combustion product of F1 race cars.--Stone 11:11, 5 April 2006 (UTC)[reply]

I understand what Stone is implying here: he is saying the combustion products should not be so "high" in the article. I think the section is important, but since the oxides are under compounds anyway, the compounds section might be a more appropriate spot for that material. Olin 21:49, 5 April 2006 (UTC)[reply]

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