|This article is of interest to the following WikiProjects:|
Formation of transuranic elements
"All of the elements with higher atomic numbers, however, have been first discovered artificially, and other than plutonium and neptunium, none occur naturally on earth. They are all radioactive, with a half-life much shorter than the age of the Earth, so any atoms of these elements, if they ever were present at the earth's formation, have long since decayed."
Surely this is wrong? For example, if an element has a half life which is a quarter of the age of the earth, one would expect a sixteenth of the original number of atoms to be currently present. I think this needs rewording. [ManInStone]
- The problem is the phrase "shorter than the age of the Earth". That information is a necessary part of the discussion, but is perhaps not the best qualifier for "half-life" given that the half-lives of elements from 100 to 118 range from 101 days to 0.89ms (see ). Calling such short times "much shorter than the age of the Earth" doesn't really provide the reader with the appropriate sense of scale. 188.8.131.52 (talk) 11:24, 25 January 2009 (UTC)
Presumably at least some transuranic elements are formed in supernovae (see for example http://books.google.com/books?id=MfAGpVq8gpQC&pg=PA119&dq=transuranic+elements+supernova). 184.108.40.206 (talk) 03:01, 24 April 2012 (UTC)
Island of stability
Would this need some discussion on the speculative "Island of Stability" of transuranic elements? Even if this was thoroughly discredited it'd be nice for the reader to find out that this was so (I have no clue). -- MartijnFaassen
The assertion that the Dubna results have been discredited is not reflected in the Element naming controversy entry, where it is treated merely as a claim made by one side in the controversy. For consistency, either beef it up there or water it down here :) Joestynes 09:01, 25 Aug 2004 (UTC)
- A group at the Joint Institute for Nuclear Research in Dubna in Russia (then the Soviet Union) who claimed to have produced:
- 104, which they named kurchatovium after the Soviet chemist Igor Kurchatov.
- 105. Although their claim is disputed, the name dubnium is now official for this element, named after the city where they worked. They originally proposed nielsbohrium for this element.
- 106. now known as seaborgium
- 107. bohrium
I removed the above section from the article as I couldnt find any confirmation that these claims had been discredited. RIP-Acer 19:30, 15 May 2007 (UTC)
Def: Super-heavy element?
I think Super-heavy atoms/elements aren't defined to be elements with Z > 104. I think there is no formal definition, but the term SHE/Super-heavy element began to occur in the same context as the island of stability around originally 114 and later around a hypothetical local stability maximum around there. If we hypothetically assume that we ourselves defined a Super-heavy element, it would be in a Z/N diagram where the stability derivative sloope down towards that hypothetical local stability maximum. I think the text shall not define 104 as the defining criterion for a SHE. ... said: Rursus (bork²) 14:40, 22 February 2009 (UTC)
What does "Discovered artificially" really mean? You can produce an element "artificially" in a laboratory, and you can discover something you have produced artficially, if the product was not created consciously and on purpose, but how can you discover artificially anything?
- Poor phrasing. Changed to "discovered in the laboratory", which is also somewhat unclear though, but hopefully the text around that sentence will help. Materialscientist (talk) 10:45, 9 October 2009 (UTC)
Are transuranium elements significant?
I suppose so (since there is a nobel price), but I do not find an application or hint about its significance in this article. —Preceding unsigned comment added by 220.127.116.11 (talk) 13:58, 12 October 2009 (UTC)
How much do these cost?
It would interesting to know how much it costs to produce these. Where can we find information on the budgets these researchers have? Shouldn't the Guinness Book of World Records list these as the world's most expensive substances? —Preceding unsigned comment added by 18.104.22.168 (talk) 02:23, 23 October 2009 (UTC)