Talk:Nuclear transmutation

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Distinction between alchemy and nuclear reaction[edit]

I suspect this article would be clearer with an explicit distinction between alchemy and nuclear reaction. Indeed the second could be there rather than here. --Henrygb 15:57, 28 Nov 2004 (UTC)

Long-lived fission products[edit]

Medium-lived FPs per 106 thermal 235U
Nuclide Halflife Yield
Eu-155 4.76 <330
Kr-85 10.76 2717
Cd-113m 14.1 <3
Sr-90 28.9 57518
Cs-137 30.23 60899
Sn-121m 43.9 0.3
Sm-151 90 <4203
Long-lived FPs per 106 thermal 235U
Nuclide Halflife Yield
Tc-99 211,000 60507
Sn-126 230,000 236
Se-79 295,000 508
Zr-93 1.53 my 62956
Cs-135 2.3 my 63333
Pd-107 6.5 my 1629
I-129 15.7 my 6576

This text needs checking.. "Isotopes of plutonium and other actinides tend to be long-lived with half-lifes of many thousands of years, whereas radioactive fission products tend to be shorter-lived (most with half-lifes of 30 years or less)." I thought that isotopes with short long half-lives could occur just about anywhere on the periodic table. -- 14:32, 19 July 2005 (UTC)

in fact most radioactive isotopes (actinides or otherwise) have short half-lives ( < 1 day) and there are plenty of long-life isotopes among non-actinides. source: [1] partial list of isotopes with long half life (> 1 year)
10Be 1.5 e+6 y
22Na 2.6019 y
26Al 7.17e+5 y
32Si 150 y
36Cl 3.01e+5 y
39Ar 269 yhfhfhuyfhi
42Ar 32.9 y
40 K 1.277e+9 y
41Ca 1.03e+5 y
48Ca 6e+18 y

Not a single one of them is formed in nuclear fission.

The point is in the "tend to". It is true that both minor actinides and fission products contain both long- and short-lived nuclides, but in spent nuclear fuel, the proportion of long-lived isotopes in the fission products is negligible, while minor actinides consist mostly of long-lived isotopes. --Philipum 08:36, 2 August 2005 (UTC)

I've added a table of the seven long-lived fission products at right, and medium-lived FP at left. The isotopes cited by the poster above are all below the mass range for fission products.--JWB 22:28, 9 June 2007 (UTC)

Fission products tend to have many extra neutrons, giving them short half lifes. That is, they are relatively far from stable nuclides. Pu-239 comes from U-238. Additional neutrons without fission will generate Pu-240, Pu-241, and Pu-242, not so far off, and longer half life. Gah4 (talk) 08:50, 13 October 2016 (UTC)

Don't confuse atomic physics with alchemy[edit]

I added a bit about gold and lead, since the matter is open to misunderstanding.

I don't think alchemists even recognised gold as an element - they mostly subscribed to the Greek theory of the Four Elements, Earth, Fire, Air and Water. On that basis you could get gold just by changing the mix, but this was wrong.

--GwydionM 17:28, 15 January 2006 (UTC)

Hmm not exactly, Alchemists rely on duality more than on the four elements. In some sense they are near of modern chemistry (Acid/base, Reduction/Oxidation, etc)

Note that the chain from gold to lead in the main section induces to error, because while the whole balance is exotermic, some of the intermediate products are not. Particularly compare 201 Hg with 197 Au. In fact, it is energetically better to transmute Hg to a mix of Au and Pt, see for the detailed balance. Arivero 15:03, 28 June 2006 (UTC)

Accelerated radioactive decay[edit]

Googling this with "magnetic field" brings up only creationists who use it as an excuse for why radioactive decay rates seem to suggest an Earth too old for creationism. Is there any genuine scientific reference to this? Ken Arromdee 18:04, 16 June 2006 (UTC)

This article cites the Spallation Neutron Source as a Photoneutron example. It does not use photons, but rather PROTONS which are accelerated and used to bombard the samples to induce the nuclear reaction generating the neutrons. This needs to be changed. It is not a good example of the use of photon energy or gamma rays for the purpose of inducing transmutation

Transmutation with Brown's gas[edit]

What do you think of this paper? Completely bogus? They speak about Kervran as if he was onto something... — Omegatron 17:43, 9 June 2007 (UTC)

Although Omegatron is not any longer active in Wikipedia, I will respond to this question, maybe it's interesting for others:
For me, the paper looks like bogus. At least I found a document [2] that states that "A. Michrowski (Planetary Clean Energy Association) presented 'Advanced Transmutation Processes,' in which he attempted a survey of cold transmutations" on a conference at the Texas A&M University. (My English language skills are not good enougth to decide whether "attempted" is a bit deprecatory or not.) Also, the paper itself does not cite very reliable sources. And Kervran is as labeled as "Nobel Nominee", although the nominees of the Nobel prize are never published nor they are told that they are being considered for the prize. So, this seems to be a lie. Instead, he received an Ig Nobel Prize.
--Cyfal (talk) 12:22, 4 February 2016 (UTC)

That part about lead turning into gold[edit]

looks ugly —Preceding unsigned comment added by (talk) 08:04, 9 May 2008 (UTC)

Not only that, but the (common, denigrating, uninformed) assertion that a major goal of alchemy was Pb->Au is simply incorrect. One way to discover this is to read Carl Jung's studies of alchemists. Like science, alchemy had its pretenders/charlatans/quacks ... and the assertion no doubt had some nudge-nudge value in applying for alchemy research grants.
However they individually viewed their real efforts (shrouded in deep code), their efforts were more like experimental chemistry than usury. It's more than a little notable that a mind like Newton's was swept in *after* he'd done the heavy math/physics lifting. I view them as transitional figures in the shadowy interregnum between unverified beliefs and verifying observation (lost since the Greeks). Twang (talk) 19:46, 1 December 2008 (UTC)

I removed the half life listed for Pb-204 because the number given is a lower bound. It has never been observed to decay. Xit vono (talk) 00:38, 29 December 2015 (UTC) says > 1.4e17 years, and alpha decay. That should be a reliable source. If there is a nuclide with the appropriate energy, the decay can be predicted. I don't know if that is what they did, though. Gah4 (talk) 08:58, 13 October 2016 (UTC)

The quote[edit]

After reading the article I noticed this page needs quite a few citations. I would like to use that quote for an assignment however teachers for some reason or other despise wikipedia. So i ask can proper citations be given for this article it would be greatly appreciated.—Preceding unsigned comment added by (talk) 05:18, 9 March 2009 (UTC)