Talk:Cobalt
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Article changed over to new Wikipedia:WikiProject Elements format by Dwmyers 16:31 Feb 20, 2003 (UTC). Elementbox converted 14:57, 2 July 2005 by Femto (previous revision was that of 00:39, 15 May 2005).
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[edit] Information Sources
Some of the text in this entry was rewritten from Los Alamos National Laboratory - Cobalt. Additional text was taken directly from USGS Cobalt Statistics and Information, from the Elements database 20001107 (via dict.org), Webster's Revised Unabridged Dictionary (1913) (via dict.org) and WordNet (r) 1.7 (via dict.org). Data for the table was obtained from the sources listed on the subject page and Wikipedia:WikiProject Elements but was reformatted and converted into SI units. —The preceding unsigned comment was added by Dwmyers (talk • contribs) 16:31, 20 February 2003 (UTC)
K.H.J. BUSCHOW (ed.), Handbook of magnetic materials, volume 12, 1999 Elsevier page 126 for the hcp->fcc transition. —The preceding unsigned comment was added by Marc Tobias Wenzel (talk • contribs) 17:01, 20 May 2003 (UTC)
[edit] Cobalt bomb?
Wasn't there some fear back in the '50s (on up to the '70s, as I recall it mentioned on The Bionic Woman of all things) that a Cobalt bomb could destroy the atmostphere of the earth? Would be interesting to see some discussion of that here. A brief search on Google turns up nothing. (now that I spelled it right (habit from correcting people who spell COBOL cobolt!) I found several references: Leo Szilard called the cobalt bomb a "doomsday" device since it was capable of wiping out life on earth.)-justfred —The preceding comment was added on 16:24, 20 December 2001.
See wikipedia's hydrogen bomb or nuclear weapon - "Another variant uses Cobalt in the shell, and the neutrons convert the Cobalt into Cobalt 60, a powerful long-term emitter of Gamma rays. The primary purpose of this weapon is to create extremely radioactive fallout to permanently deny a region to an advancing army, a sort of wind-deployed mine-field. It was actually tested by the British in Central Australia, in areas that remain uninhabitable to this day." The fears over destroying the atmosphere were applied to the first atomic tests. —The preceding unsigned comment was added by 62.253.64.xxx (talk • contribs) 16:34, 20 December 2001 (UTC)
MSM: actually the cobalt-salted bomb became the ultimate terror weapon, and its qualities continued to change and grow more fearsom with every telling. After Szilard foolishly referred to it as a "doomsday device" it was all downhill from there.
Basically he was trying to demonstrate that there are particular effects of bombs that could render an area useless to humans, and the several-year-deadly fallout from a cobalt bomb was the perfect example. What needs to be clear is the amount required though, the Earth is a VERY big place! If you consider a 10ft radius bomb containing powder, you'll see the problem.
However once it was out, it was out. Soon you had all sorts of stories of a single bomb going off and wiping out the entire planet forever. But that wasn't enough, and new and more interesting effects were then invented for it, including what you note above. —The preceding unsigned comment was added by Maury Markowitz (talk • contribs) 18:06, 6 September 2002 (UTC)
CMB: Along with "nuclear winter," part of the repertoire of public stone age superstition about nuclear war. Cobalt weapons produce longer lived by-products and would require longer stays in shelter. To achieve the science fantasy consequences of ON THE BEACH, it would be necessary to detonate a bomb with a cobalt warhead about the size of the moon, so it seems it might be easier to just drag the moon into the earth if you wanted a maximum result in fatalities.
A lot of this stuff, once registered in the feeble collective unconscious of mankind, is there to stay and common sense doesn't stand a chance of dislodging it. —The preceding unsigned comment was added by 211.27.131.67 (talk • contribs) 01:36, 9 October 2004 (UTC)
MV: I have seen in some websites that the cobalt could not be placed in the shell as in order to absorb the biggest amount of neutrons, it would have to be in the tamper. And t is claimed that 33.6 tons would be enough to cover all the earth's landmasses. Is there some validity to that? --151.198.130.79 03:23, 17 January 2006 (UTC)
Correct. Szilard's idea was that the tamper would contain the cobalt where a more "traditional" bomb would contain additional fissionable materials. Most radioactive fallout will precipitate out of the atmosphere in a matter of days, but the fallout created by a so-called cobalt bomb remains suspended in atmospheric gases, so that it remains radioactive until it decays into a non-radioactive form. Sziland further proposed that the bomb itself should work by hydrogen fusion rather than the famomiliar fission method, hence the term "hydrogen-cobalt bomb". Given the greater power of hydrogen fusion as opposed to fission, Szilard estimated that 500 "hydrogen-cobalt bombs" could destroy the population of the world. Notice he says COULD, not WOULD. And when he says that, he optimizes the spacing of the detonations relative to one another. Nonetheless, he's right. You could indeed create a situation in which global wind patterns would carry the fallout around the globe and create enough fallout that the entire atmosphere of the earth would become lethally contaminated in two or three years, and we'd all die of radiation poisoning. Szilard suggests that the cobalt would decay to a harmless isotope thereof in about twenty years, so presumably if you could shelter yourself underground for that long you could survive. More recent studies, however, suggest that it might take several times that long for the decay to take place, and that you might have to shelter yourself for fifty, a hundred or several hundred years. That part is disputed. The earth, as a correspondent has stated above, is a big place, but the power of hydrogen fusion is also big. The bottom line is that it's a question of amount. "The size of the moon" is a strange estimate, given the power of fusion. Tom 129.93.17.115 03:20, 6 December 2006 (UTC)
[edit] Covert Iron into Cobalt?
~~MV~~
I think there has been a little mistake in the article. The way is written gives the impression that any iron (and therefore steel) would turn in great part or totally in Cobalt 60. I think it would be better to clarify that cobalt 59 turns into cobalt 60 by the emission of neutrons, not any iron or steel, (there is a mention in the article of natural cobalt being able to be converted even in large quantities by exposing cobalt to neutrons, not iron or steel). Many nuclear weapons tested used steel cases and they did not all turn into cobalt 60 (Ivy Mike, for example). Some cobalt 60 results as part of the fission products and due to the use of cobalt in some alloys, but it is not all or in great part cobalt 60. The mention of iron turning into cobalt 60 can be kept, but it could probably be stressed that it would be a small amount, like other fission products. That also could point out as the next sentence intends that some nuclear weapon designs could increase the amount of cobalt 60 by using cobalt 59, rather than steel or other casing which would not produce much cobalt 60. I think that change could be made. --Mike Velasquez 01:20, 23 February 2006 (UTC)
- This appears to have already been fixed. If you feel there's still a problem, please indicate where it is, because the section discussing cobalt bombs indicates that the source of cobalt 60 is cobalt 59. By the way, you might want to consider creating a user account; it will give you a user page to put any personal information you desire, and a user talk page where others can get ahold of you. --Christopher Thomas 07:26, 25 February 2006 (UTC)
Thanks for the advice, I will consider creating an account. Don't worry, There is no problem , just thought that the mention of iron turning into cobalt should not have been changed completely for Cobalt 59, only specified that the amount of cobalt 60 would be very small with iron (and wouldn't be a more significant risk than other fission products), and then contrast it with the risk of cobalt 59 being used in a bomb. --68.162.16.204 18:44, 25 February 2006 (UTC)
[edit] kobalos
My entry from Lidell and Scott:
Κόβαλος, m, an impudent rogue, arrant knave, Ar.: -Κόβαλοι were mischievous goblins, invoked by rogues, Id. II. as adj Κόβαλα, knavish tricks, rogueries, Id. (Deriv. uncertain)
I don't in the slightest dispute that Κόβαλος is the fons of goblin, kobold, kobalt, cobalt, etc, but can someone show me a source for Κόβαλος meaning "mine"? For mine, I find this and these [1].--Josh Rocchio 01:00, 5 June 2006 (UTC)
- The/one source appears to be http://www.vanderkrogt.net/elements/elem/co.html. No idea how, or if, this holds up to your cites. You appear to know what you're talking about, do what's necessary to the article. Femto 11:28, 5 June 2006 (UTC)
[edit] c/a-ratio
I miss the c/a-ratio of hcp-cobalt. Does anybody know? SietskeEN 08:26, 22 July 2006 (UTC)
- Never mind, I already found it: the lattice constants a and c are 2.5071 and 4.0695 Å, therefore c/a is 1.623. SietskeEN 08:30, 22 July 2006 (UTC)
[edit] Decay energy of 57Co
The article states that the decay energy of Co57 is 0.833 MeV. However, I use it all the time and know that the 272-day decay produces a 122 KeV photon (and a 133 KeV with much lower probability). This is also the result of the nice applet at: http://www.nndc.bnl.gov/nudat2/indx_dec.jsp. Is the value currently printed here (0.833) a typo?
Answer to my own question: The value stated here in the decay energy (he kinetic energy available for all the decay products. This value is indeed much greater than the energy of the emitted gamma. Apparently, most of the energy for this decay is carried off by a neutrino.--PloniAlmoni 09:43, 16 November 2006 (UTC)
[edit] Image of cobalt metal
Is the image of cobalt metal included in this article really cobalt? I looked online for more images of Cobalt metal and all the other pictures I have seen look much more silvery and much less golden.
Hey Guys
In medical uses of cobalt you should mention its use as an Implant material. Its used as for dental implants when alloyed with chromium and molybdenum, refered to as "CoCrMo" in scientific journals or "Vitalium" as a tradename
cheers
Chris
