Talk:Erbium
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Article changed over to new Wikipedia:WikiProject Elements format by mav 09:24, 15 Dec 2003 (UTC). Elementbox converted 11:51, 10 July 2005 by Femto (previous revision was that of 13:44, 9 July 2005).
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[edit] Information Sources
Some of the text in this entry was rewritten from Los Alamos National Laboratory - Erbium. 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] Factual Inaccuracies?
Los Alamos lists the Melting Point as 1529? degrees Celsius. The Wikipedia Erbium page lists it as 1497 Degrees Celsius, no question mark. Why the difference? Phoenix Song 15:48, 28 September 2005 (UTC)
- The rubber bible says 1529°C also. WebElements says 1497°C. Hard to know which is right when references disagree. -- Bob Mellish 15:56, 28 September 2005 (UTC)
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- Technically, they all could be right with the appropriate uncertainty. It's a shame that even publications like the CRC commonly omit those. The melting points in the articles are referenced by melting points of the elements (data page). I chose the WebElements number as recommended value, for the simple reason that it already included converted units. The number from CRC might be more 'correct' because they further refer to a specialized reference in one place (Gschneidner). On the other hand, the CRC sometimes even doesn't agree with itself, for example whether terbium melts at 1356 °C or 1359 °C. So at this point I think neither value appears to be sufficiently better than the other to actually change the number in the infobox. Femto 17:43, 28 September 2005 (UTC)
- I'll try checking the Gmelin book for erbium, they are usually very good with references for this sort of thing. -- Bob Mellish 17:59, 28 September 2005 (UTC)
- The Gmelin rare earths handbook lists 1522°C and 1550°C as two melting points given in the literature. The most recent reference I can find (Handbook on the chemistry and physics of rare earths, vol.12 (1989) lists the 1529 figure. -- Bob Mellish 00:13, 29 September 2005 (UTC)
- I checked the World Book encyclopedia from 2002, and it lists 1529 as well. Phoenix Song 00:50, 29 September 2005 (UTC)
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- That should do it. Updated the data page and changed the article to 1529 °C. I don't have access to Gmelin. It would be great if you could find some spare time to also check and expand some of the other chemical elements data references. Femto 11:55, 29 September 2005 (UTC)
[edit] Reverse Velocity Light and Faster than Light Application
Robert Boyd of Rochester University in New York led a team that used an optical fiber laced with the element erbium to generate two discoveries related to light. The first discovery was that the line cloned the peak of the light wave at the exiting end before the peak finished entering the original end of the line. This process allowed the light to exit the line at a speed faster than the known current speed of light. The cloned peak also generated a light wave travelling at negative velocity, which travelled back along the optical fiber to cancel out the original light wave before it exited the optical line. This process was repeated by the lab using varying lengths of optical fiber to isolate and verify the process, and an independent experiment at the Universität Karlsruhe in Germany found a very similiar effect using an unknown material.
Source is the Discovery Channel webpage at http://dsc.discovery.com/news/briefs/20060522/weirdlight_spa.html?source=rss
I am not skilled at the appropriate research and verification necessary to introduce this into the Wiki, and would appreciate it if someone else were to do the necessary steps to write this in. —The preceding unsigned comment was added by 66.196.227.130 (talk • contribs) .
- The typical oversimplified popular science style of the linked article is too vague to tell anything, I'm afraid. http://www.sciencemag.org/cgi/content/abstract/312/5775/895 looks like another instance of the known apparently faster-than-light phenomena based on phase velocity and group velocity. Interesting perpaps, but not at all related to erbium, beyond the already mentioned use as fiber optic dopant. Femto 14:51, 26 May 2006 (UTC)
