Talk:Selenium

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Article changed over to new Wikipedia:WikiProject Elements format by Dwmyers, Maveric149 and Malcolm Farmer. Elementbox converted 13:54, 1 July 2005 by Femto (previous revision was that of 02:42, 18 June 2005).

Contents

[edit] Information Sources

Some of the text in this entry was rewritten from Los Alamos National Laboratory - Selenium. Additional text was taken directly from USGS Selenium Statistics and Information, USGS Periodic Table - Selenium, 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.

[edit] Talk

[edit] Nonmetal vs Metalloid

Is Selenium a nonmetal (as per this article) or a metalloid (as per Chalcogen)? Ian Cairns 01:16, 6 Mar 2005 (UTC)

Hi. I also have noticed a discrepancy:

http://simple.wikipedia.org/wiki/Metalloid

so, if you have came to some conclusions, could you share them?

[edit] Possibly a featured article?

I find this article pretty comprehensive and think would make a good candidate for a featured article. However, it seems to be lacking in a few things which I can't quite pin-point. Leftist 14:56, 21 March 2006 (UTC)

Maybe a hint of garlic? SBHarris 19:40, 7 September 2006 (UTC)
I'd like to see a list of foods in which selenium is naturally occurring. / LNelson, 27 Aug 2007 —Preceding unsigned comment added by 76.237.171.91 (talk) 12:55, August 27, 2007 (UTC)

[edit] Typography

I don't have strong opinions about this, and I can understand why most people would never think of representing mu the way I originally did, but I think 100μg is rather clearer than 100μg . I think it must be the lack of curved lines on the standard μ . Elroch 16:47, 10 April 2006 (UTC)

The <math> markup is altogether undefined with respect to the standard browser fonts; 100 μg looks horrible on my system. The micro sign µ is typographically unambiguos. It's a different beast from the character entity &mu; (in any coding) for the Greek language letter μ, which should not be used as a substitute for the micro prefix for this reason. Femto 18:51, 10 April 2006 (UTC)
The mu I used, μ, just looks like a more curvy mu in Internet Explorer 6.0 and Firefox 1.5: presumably you are using a different browser. I was not aware there was a separate symbol for "micro". I thought the use of a lower case Greek letter was standard - did you not use the letter from the Greek alphabet at the bottom of the editor window? Elroch 20:31, 10 April 2006 (UTC)
No I don't have JavaScript enabled. Around here, I can enter the ISO 8859-1 code $B5 directly from my keyboard (Want some € too? :). You can always substitute with the HTML entity &micro; (µ). Theoretically, the lower case Greek mu &mu; (μ) is standard; it should also appear typographically consistent with the ordinary text for everybody, though for historical coding reasons the separate micro is kept for the units. Femto 21:17, 10 April 2006 (UTC)
It certainly looks exactly the same on my two browsers. Whether it would on all others is another matter. Elroch 00:41, 11 April 2006 (UTC)

[edit] Selenium and Mercury

Should information that selenium counteracts the negative effects of mercury be added?

MSTCrow 12:11, 17 June 2006 (UTC)

[edit] HIV/AIDS

While it's true that people have existed in sub-Saharan Africa for longer than the AIDS epidemic, it does not follow that they have had selenium deficiency since before the AIDS epidemic. Furthermore, assuming that they did, it does not follow that they should have had AIDS then; the HIV virus is a necessary condition for AIDS and lacking (or predating) its existence, the contributory selenium factor (assuming it exists) is rendered moot.

The "fact" that copper-mining produces selenium as a by-product (source? I find it implausible that the existence of one raw element necessarily requires the existence of another) doesn't imply that said by-product is sufficiently present in agricultural soil and therefore in food. Therefore, nothing about copper-mining necessarily has any effect on selenium deficiency in areas in which it exists.

The lack of a published standard of what is subjectively considered "low" has no bearing on the fact that selenium, as a physical and measurable element, can be objetively found to be lower or higher in the diets of some regions. This is all that is needed to establish a negative correlation between dietary selenium and severity of the AIDS epidemic. 140.247.248.52 12:09, 7 September 2006 (UTC)

Actually, a study was just published about the effects of Selenium on the HIV virus [1]. I'm not sure if it's totally accurate, as the server that hosts the study is down for an hour or so, but it would certainly be worth looking into.Ahudson 18:13, 23 January 2007 (UTC)
It's all over Google News, so it can at least be referenced in a preliminary fashion from journalistic sources. Elijahmeeks 06:40, 24 January 2007 (UTC)

[edit] Need this info

Whats the cost per gram??? and the number of electrons at solid state??? i needed this for project and couldn't find it —The preceding unsigned comment was added by 70.18.122.163 (talk • contribs) 23:41, 3 December 2006 (UTC).

Prices are usually not given for elements, since they vary greatly according to purity and form. And change with time and supplier. I don't understand your question on electrons. What does solid state have to do with it? Generally the number of electrons her atom for isolated elements is the same as the atomic number. SBHarris 01:11, 4 December 2006 (UTC)


[edit] Early reference to photovoltaic effects

I was doing some research in The Times of 1921, and on 24 September 1921 pages 6 and 8 there are articles on the use of selenium in an early "talkie" (film + phonograph recording). Jackiespeel 18:14, 12 February 2007 (UTC)

[edit] Fact tag to Isotope section

Hi there,

I have just been dealing with some vandalism at Badminton where I noticed the only other contribution of the anon IP was some time ago on this article see [2]. Basically I have added fact tag because the information on the number of isotopes and how many are stable needs referencing and of course the edit by the anon IP may have added incorrect information, and need verification.

Cheers Lethaniol 15:39, 15 February 2007 (UTC)

Gave the section an overhaul, reference is isotopes of selenium. Femto 16:14, 15 February 2007 (UTC)


[edit] Allotropes

Is the red form really an allotrope, or an oxide?--THobern 10:24, 23 April 2008 (UTC)

[edit] Reference to Evolution_(film)

I added the reference to the movie Evolution as i felt that selenium was such a key component and the 'savior of the day'. I hope this doesn't need a spoiler warning! Megatonman (talk) 18:46, 14 May 2008 (UTC)