gmelancon Posted December 3, 2014 Posted December 3, 2014 I am an engineering student, but I would like to perform some experiments unrelated to my studies. I originally thought that getting liquid nitrogen would require a license, but a relative who works in the liquid air industry said that was not the case. So now that I can get my hands on liquid nitrogen fairly inexpensively, I just need the wire material. I would like something flexible enough to shape when room temperature, that only needs liquid nitrogen to become superconducting. My search has only led me to wires that need liquid helium. Any help, like a particular material to look for or a company to look at, would be appreciated. Thanks in advance
mathematic Posted December 4, 2014 Posted December 4, 2014 http://hyperphysics.phy-astr.gsu.edu/hbase/solids/hitc.html You could start here. Also Google "superconducting materials".
Enthalpy Posted December 5, 2014 Posted December 5, 2014 I can't tell for your country, but liquid nitrogen is easy to get here in old Europe. If the supplier doesn't want to deliver a litre, just go to the next lab (chemistry, microelectronics, and so on) with a container made of polystyrene foam and kindly ask to fill it. High-temp superconductors are still uncommon presently, worse in the form of wires, and even worse as womewhat malleable material. This is one big hurdle to their banal use. You might try your luck at the producers ( www.suptech.com , Bruker HTS GmbH , and several more). Though, it may be difficult. Somewhat easier would be a superconducting thin film, rather than wires. At liquid helium temperature, many metals superconduct. Liquid He is a bit expensive, and if improperly stored or used, is quickly lost. Though, if you really need wires, this may be an easier route. CERN has published online an excellent introduction to superconductivity by Sonneman within a "quench analysis" document but apparently it's gone. You might read other courses online.
haram Posted March 20, 2016 Posted March 20, 2016 (edited) This guy claims that he reached above 150C/300F. Although he looks very seriously, I didn't find any peer-review opinion on his work. Could that be correct, or somewere is a huge glitch? http://www.superconductors.org/158C155C.htm http://www.superconductors.org/ Edited March 20, 2016 by haram
imatfaal Posted March 22, 2016 Posted March 22, 2016 He seems to be testing and claiming results for lots of the side issues related to superconductivity rather than the real deal. And unfortunately anything that starts with a screed against established science, has bad graphics, says how long the author has been doing this etc scores very high on the crackpot bingo card
haram Posted March 27, 2016 Posted March 27, 2016 He seems to be testing and claiming results for lots of the side issues related to superconductivity rather than the real deal. And unfortunately anything that starts with a screed against established science, has bad graphics, says how long the author has been doing this etc scores very high on the crackpot bingo card Agreed on that generally, but meanwhile I found that he is getting some affirmations: http://nextbigfuture.com/2011/12/joe-eck-at-superconductorsorg-claims.html http://nextbigfuture.com/2009/10/confirmation-of-ultra-ycbo.html Also is interesting comment in first link: "It's because he looks at comparatively tiny glitches in resistance vs. temperature traces and magnetization vs temperature traces, and claims that these are due to superconductivity. There are many other transitions (structural and magnetic) that can produce such glitches, besides superconductivity. It's a *big* step with no supporting evidence to claim that a fraction of a percent change in total resistance is *really* caused by some amount of material going down to zero resistance. *If* his attribution is correct (and that's a big "if"), it means that some tiny volume fraction of his material, of unknown composition (certainly not the nominal total composition), is doing something. People would be much more interested in this work if he could actually make a macroscopic amount (in this case, even few mg would be nice) of single-phase material with well defined composition." ... and this one too: In theory, if he is producing a material with small domains of superconductivity, he should be able to take his pellets, grind them finely, and perform a magnetic separation on them in order to produce a fraction highly enriched in superconducting domains. Perhaps it's time for him to do that. Is that indicating that Ecke could be on traces of SC nevertheless?
imatfaal Posted March 29, 2016 Posted March 29, 2016 Agreed on that generally, but meanwhile I found that he is getting some affirmations: http://nextbigfuture.com/2011/12/joe-eck-at-superconductorsorg-claims.html http://nextbigfuture.com/2009/10/confirmation-of-ultra-ycbo.html Also is interesting comment in first link: "It's because he looks at comparatively tiny glitches in resistance vs. temperature traces and magnetization vs temperature traces, and claims that these are due to superconductivity. There are many other transitions (structural and magnetic) that can produce such glitches, besides superconductivity. It's a *big* step with no supporting evidence to claim that a fraction of a percent change in total resistance is *really* caused by some amount of material going down to zero resistance. *If* his attribution is correct (and that's a big "if"), it means that some tiny volume fraction of his material, of unknown composition (certainly not the nominal total composition), is doing something. People would be much more interested in this work if he could actually make a macroscopic amount (in this case, even few mg would be nice) of single-phase material with well defined composition." ... and this one too: In theory, if he is producing a material with small domains of superconductivity, he should be able to take his pellets, grind them finely, and perform a magnetic separation on them in order to produce a fraction highly enriched in superconducting domains. Perhaps it's time for him to do that. Is that indicating that Ecke could be on traces of SC nevertheless? Not really no. They are both saying quite politely that the evidence provided is sorely lacking and that testing transitions is all very well but superconductors have two stand out and very testable properties - no resistance and the expulsion of the magnetic field; both posts suggest that some evidence of this, which would be obtainable if (and it is a big if) the substance is superconducting, is completely essential to any claim.
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