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  1. 10 Aug '10 16:46 / 1 edit
    I have been off the net for a year and I would think this might have been already mentioned on a past thread on this science forum but I have searched and couldn’t find it in this forum and I thought this is such a significant breakthrough in superconductor research that it would be worth mentioning here just in case it hasn’t already been mentioned:

    http://www.superconductors.org/254K.htm

    A -19C superconductor is certainly news to me but, as I have said, I have been off the net for a year.

    I have also been searching the net for other news on high-temperature superconductors and my general impression from websites such as:

    http://www.physorg.com/news134828104.html

    -is that, although we still don’t fully understand the phenomenon, real progress is being made in understanding how it may be possible to make it work at room temperature.

    -could it be that we would soon have room-temperature superconductors? if so, how soon –I wonder.
    Would anyone here dare make a prediction?
    And do any of you suspect, like some scientist think, room-temperature superconductor is actually physically impossible!?
  2. 10 Aug '10 17:05
    If this -19C superconductor is real, then room temperature superconductors are not far away, especially considering we don't really understand high-Tc-superconductivity yet so it would be very unlikely we are near the theoretical limit.
  3. Standard member sonhouse
    Fast and Curious
    10 Aug '10 23:48 / 2 edits
    Originally posted by KazetNagorra
    If this -19C superconductor is real, then room temperature superconductors are not far away, especially considering we don't really understand high-Tc-superconductivity yet so it would be very unlikely we are near the theoretical limit.
    First I heard of it and I look at the journals all the time. I hope it proves out. We need room temp supers for sure but what would be more useful would be supers that work at 200 degrees C! Of course I'll take RT supers for sure!

    First thing I want to do is to characterize dipole antennas using them. I thought they would lead to super hi Q antennas and super hi Q filters and such leading to maybe a 40 DB gain in receiver sensitivity for use by hams, radioastronomers and such, radar also.

    One report I recently read says otherwise. I thought the Q of a filter or antenna was the ratio of the impedence over the ohmic restistance, so as the ohms go to zero, the Q goes to infinity.

    Of course an infinite Q would be rediculous, as useful as tits on a boar hog but Q's in the thousands should really help.

    One paper I read about says it doesn't change the Q much over a standard copper or silver wire.

    I hope to prove that false. I tried to get American Superconductor to sell me a length of high temp wire (superconductive in LN2) but they thought my project worthless or trivial and refused to do business with me. I don't think such a project to be trivial. If the Q really does go up if you use a superconductor it would help many aspects of communications electronics.

    It wasn't as if I was asking for a freebie, they refused to SELL me some. I am dying to get my hands on some, even ten feet of wire would help. 70 feet would be incredible! That is the length of a 40 meter band amateur antenna. Sigh.
  4. Standard member sonhouse
    Fast and Curious
    11 Aug '10 00:01
    Originally posted by Andrew Hamilton
    I have been off the net for a year and I would think this might have been already mentioned on a past thread on this science forum but I have searched and couldn’t find it in this forum and I thought this is such a significant breakthrough in superconductor research that it would be worth mentioning here just in case it hasn’t already been mentioned: ...[text shortened]... , like some scientist think, room-temperature superconductor is actually physically impossible!?
    One thing I noticed about this group, Superconductor.org, in its list of articles is this one on gravitomagnetism with spinning superconductors:

    http://www.sciencedaily.com/releases/2006/03/060325232140.htm

    I think this one was proven to be totally wrong if not a hoax.
  5. 11 Aug '10 09:41 / 1 edit
    Originally posted by sonhouse
    One thing I noticed about this group, Superconductor.org, in its list of articles is this one on gravitomagnetism with spinning superconductors:

    http://www.sciencedaily.com/releases/2006/03/060325232140.htm

    I think this one was proven to be totally wrong if not a hoax.
    When somebody talks about an “anti-gravity effect”, I think one should always be suspicious.
    But what they are suggesting doesn’t seem too extraordinary to me. I mean, it isn’t as if they are claiming/implying it is possible to make a practical anti-gravity machine that can launch us into space!
    Are you sure this one was proven to be wrong?
  6. Standard member sonhouse
    Fast and Curious
    11 Aug '10 13:25 / 1 edit
    Originally posted by Andrew Hamilton
    When somebody talks about an “anti-gravity effect”, I think one should always be suspicious.
    But what they are suggesting doesn’t seem too extraordinary to me. I mean, it isn’t as if they are claiming/implying it is possible to make a practical anti-gravity machine that can launch us into space!
    Are you sure this one was proven to be wrong?
    I'll see if I can find links, but I am pretty sure other researchers found no such effect.
    If such an effect existed, why would it have to be a superconducting piece? There should be an analogous effect even with copper or silver, at least IMO.

    Personally I would love for that effect to be real. If real, it could lead to a real space drive. Maybe not strong enough to get you off the ground and into space but once there, almost any thrust gets you anywhere in the solar system.

    I just think the effect isn't real.

    I found this Wiki about the subject:

    http://en.wikipedia.org/wiki/Gravitomagnetism

    There are experiments to detect GM using the Gravity B probe, I think still in orbit and producing data.

    Note the end of this article basically poo-poo's the antigravity idea.
  7. Standard member sonhouse
    Fast and Curious
    11 Aug '10 18:15
    I found Johan Prins' email address, and am corresponding now. Will see what he says about superconductivity. He claims to have room temp + superconductors made on electronic grade semiconductor substrates. I would like to see that verified, he claims he is being shunned by the physics community, prevented from publishing and the like. My son in law is a statistical physicist, I will show him the site, maybe he can tell if its a hoax. Wouldn't it be a blast if he actually is the one who cracks room temp superconductivity? Why would the physics community shun something like that? Here is the link to his company: He retired from the University of Pretoria now has his own website:

    Dear Don,



    As you can see Johan Malherbe graciously forwarded you e-mail to me. I am now retired and working for myself. You can contact me anytime at this e-mail address. If you are interested my website on superconduction is at www.cathodixx.com
  8. 12 Aug '10 06:44
    Originally posted by sonhouse
    If you are interested my website on superconduction is at www.cathodixx.com
    I looked up the site and my web filtering software labels it "Alternative Spirituality / Occult"

    So here we have someone claiming to have a major breakthrough, yet is being shut out of the physics community, and instead of selling his superconducting products, chooses to write books about "the physics delusion".
  9. Standard member sonhouse
    Fast and Curious
    12 Aug '10 08:11
    Originally posted by twhitehead
    I looked up the site and my web filtering software labels it "Alternative Spirituality / Occult"

    So here we have someone claiming to have a major breakthrough, yet is being shut out of the physics community, and instead of selling his superconducting products, chooses to write books about "the physics delusion".
    That's pretty much what I was trying to point out. I wanted to see if this guy would respond. If he had a true room temp SC, the world would be set back on its ear and there would be newshounds at his door 24/7 and the Nobel prize would have him on a short list.

    Writing about delusions and such does not seem to me the best way to go about proving a breakthrough. A news conference would be the way to go, assuming he really has been shut out of the scientific community.

    People have been shunned for sure. One in particular that ticked me off, was the shunning of Carl Sagan. He was a real scientist who predicted the runaway greenhouse effect on Venus and predicted temperatures close to a thousand degrees on the surface. In spite of that, and because of his publication of lay books and his Cosmos show and movie, he was denied membership in the science associations he always wanted. I thought that was a shameful affair. He was dismissed as a 'mere populist'.
  10. 14 Aug '10 09:44
    I found a claim that “Inexplicable Superconductor Fractals Hint at Higher Universal Laws”:

    http://www.wired.com/wiredscience/2010/08/superconductor-fractals/

    But I am having doubts with the credence of this claim –doubts made worse by the annoying observation that the article only refers to temperatures using the obsolete and rather dated Fahrenheit scale and never in centigrade! Why would a credible modern science article do that? –I have no idea.
  11. Standard member sonhouse
    Fast and Curious
    14 Aug '10 23:41 / 3 edits
    Originally posted by Andrew Hamilton
    I found a claim that “Inexplicable Superconductor Fractals Hint at Higher Universal Laws”:

    http://www.wired.com/wiredscience/2010/08/superconductor-fractals/

    But I am having doubts with the credence of this claim –doubts made worse by the annoying observation that the article only refers to temperatures using the obsolete and rather dated Fahr ...[text shortened]... and never in centigrade! Why would a credible modern science article do that? –I have no idea.
    A bit suspicious for sure but not the nail in the coffin. Can you hear that coffin sound?
    The Johan Prins thing, I just got a more detailed email from him, I'll post it for you.
    My questions are in quotes, his answers are not:


    "So with this superconductivity you have worked out, can you make wires?"

    No, only wafers

    " It sounds like you are using CVD or sputtering machines to get your product. My field is Ion Implanters and sputtering machines, my last company was Inplane Photonics, we built a cleanroom from a bare concrete floor ...."

    You have experience with the techniques I am using,

    " Anyway, one project I have had in the back of my mind is making RF circuitry"

    A material cannot superconduct when you have an ac-current. It is a dielectric and such a current will always vibrate dipoles and emit EM-radiation.

    " I don't know if you use semiconductor foundries or if you have your own cleanroom (we really benefitted from having our own cleanroom at Inplane Photonics for research) but if you do, I am available, I would love to get the hell out of the US again."

    I do not have these facilities and cannot afford them.


    I hope this is of help,


    Regards,

    Johan


    PS: I left an answer on my website forum.



    (I found a forum on his website and asked some hardware specific questions, he mentions you have to have ''High Tech" multimeter to see the measurements he is talking about)

    He is basically talking about what, if true, amounts to a form of superconductivity but only on wafers of a specific type. It has to do with a current between two layers that seem to generate some kind of current flow but with no voltage between the layers based on some kind of quantum effect.

    I don't pretend to know the details but I am pretty sure if he says you need a 'high tech' multimeter, he may be misunderstanding the rules of engagement of such instruments. He may be only thinking he is seeing a no voltage situation when in fact it is due to using the wrong instrumentation.

    He may need to do some other form of sensor rather than that multimeter, an instrument I am fully familiar with, the 'high tech' ones, not the radio shack style 30 dollar meters you see good for 3 digits of accuracy.

    He is probably referring to the more advanced ones that feature 8 digits or more of accuracy and basing his whole schtick on misunderstood instrumentation. Without seeing the exact setup, that is the most likely explanation I see, Occam's razor:
    "Entia non sunt multiplicanda praeter necessitatum" William of Ockham Ca 1325.

    Even if true, as he admits in his email to me, it can only be applied to semiconductors and of those only diamond, a special brand of semiconductor that is a pain in the asss to dope to conductivity.

    So even if true, it has no bearing on the real world, such as superconductive power transmission, but he is basing his whole rather precarious scientific credibility on this one measurement. I also don't hear of other labs reproducing his result, maybe because it can't be verified. Not totally sure of that but that is what I suspect. He claims it is because he has been blackballed.
  12. 15 Aug '10 07:49
    Originally posted by sonhouse
    A bit suspicious for sure but not the nail in the coffin. Can you hear that coffin sound?
    The Johan Prins thing, I just got a more detailed email from him, I'll post it for you.
    My questions are in quotes, his answers are not:


    "So with this superconductivity you have worked out, can you make wires?"

    No, only wafers

    " It sounds like you are u ...[text shortened]... that is what I suspect. He claims it is because he has been blackballed.
    “…A material cannot superconduct when you have an ac-current. It is a dielectric and such a current will always vibrate dipoles and emit EM-radiation….”

    Obviously I am no expert on this but I have never heard of superconductors not being able to have ac-current and don’t understand his explanation.
    If a superconductor really could not handle ac-current then surely it would also not be able to handle square-wave pulse-current? –if so, then it would be useless for sending digital signals and thus useless for digital electronics.
    So, why all the talk about superconductors making ultra-efficient computers!?
  13. 15 Aug '10 12:00
    Originally posted by Andrew Hamilton
    “…A material cannot superconduct when you have an ac-current. It is a dielectric and such a current will always vibrate dipoles and emit EM-radiation….”

    Obviously I am no expert on this but I have never heard of superconductors not being able to have ac-current and don’t understand his explanation.
    If a superconductor really could not handle ac ...[text shortened]... tal electronics.
    So, why all the talk about superconductors making ultra-efficient computers!?
    “…square-wave pulse-current…”

    Sorry, my mistake; that doesn’t make a whole lot of sense.
    That should be “…square-wave pulse-voltage…” and not “…square-wave pulse-current…”
  14. Standard member sonhouse
    Fast and Curious
    16 Aug '10 04:13 / 2 edits
    Originally posted by Andrew Hamilton
    “…A material cannot superconduct when you have an ac-current. It is a dielectric and such a current will always vibrate dipoles and emit EM-radiation….”

    Obviously I am no expert on this but I have never heard of superconductors not being able to have ac-current and don’t understand his explanation.
    If a superconductor really could not handle ac ...[text shortened]... tal electronics.
    So, why all the talk about superconductors making ultra-efficient computers!?
    He is talking nonsense. He is referring to the fact that a diode only conducts in one direction and calls that 'dielectric'.

    A dielectric is the insulating layer between capacitors, you have to have an insulator with as high a dielectric constant as possible to make both high voltage and high capacitance. If you have two plates X distance apart, you get Y amount of capacitance measured in Farads or Microfarads or Picofarads.

    If you introduce a insulator with a dielectric constant of 2 and the spacing and the area of the capacitor plates are the same, you will double the resulting capacitance. The dielectric strength is the maximum voltage it will take per unit thickness. Here is a wiki about this issue:

    http://en.wikipedia.org/wiki/Dielectric_strength

    You notice in this entire article there is no mention of diode action, one way flow of electricity.

    You can for sure transmit AC down a superconductive line, it is already being done but on a small scale.

    Vibrating dipoles. I think he is referring to the fact you can make AC turn into radio waves of the same frequency if you have a dipole antenna, where the length of the dipole is half the wavelength.

    For a hypothetical signal of one hertz, which would be a wavelength by definition of 186,000 miles or 299,000 Kilometers so a dipole of half that length or 93,000 miles or 150,000 kilometers would be a fairly efficient radiator of one hertz AC.

    So what we use in the US, 60 Hz, divide 90,000 by 60 and a dipole would have to be 1,500 miles long to radiate 60 Hz into space. Most long distance lines are way shorter than that deliberately, they can be tuned so it is antiradiative with proper filtering and such.

    If it is 750 miles long, it would be 1/4 wave long and not a very efficient radiator, and 500 miles, even less radiative. So theoretically he is right, AC will radiate but only if you have extremely long wires.

    Also, if you have two wires close together, not close enough to arc but a bit past that distance, in a long haul, you have one wire be the + and the other the - to use DC terminology, that further reduces the radiation of energy by turning the power lines into what are called feedlines.

    You may know them as the TV twinlead wires going from an external antenna, two wires held a certain distance apart, they inhibit radiation and feed the power at whatever frequency they are interested in down that line THEN it goes to an antenna which efficiently radiates that energy into space, like in cell phone towers.

    Every one of those antennas have feedlines, probably coaxial, which is like tv cable wiring, a conductive tube with an inner insulating layer and a wire in the center, does the same job as two wires side by side in suppressing radiation, you don't want transmission lines to radiate, you want them to conduct the energy to the antenna and IT radiates because it is designed to.

    So his statement "A material cannot superconduct when you have an AC current' is false. It is maybe only valid in his world where his supposed diamond transistors superconduct and only in one direction because a transistor is basically a diode with a controlling element.

    Superconductive wires conduct AC just fine and without radiation for the most part. You can't get away from SOME radiation even from an AC wire, a single wire, say 50 feet long but the percentage of the energy turning into radiation, say at 60 hertz is very small indeed. Enough to screw up a radio if you drive under a high tension line but it does die down as you travel away from them.

    Us hams hate the dam things, we will not knowingly buy property within a few miles of them for that reason, they do radiate but a small amount but enough sometimes to add ac hum to a received signal which has to be filtered out.

    One note on capacitors, two plates with a dielectric insulator in between, could even be air, but whatever it is, a capacitor conducts ac across it just fine, it's like a resistor reacting to DC, a bit more complex but capacitors are like shorts sometimes to RF but holds back DC.

    They can be used therefore to transmit energy across the glass of a windshield to have an antenna that does not need to have a hole cut in the roof or a cable sticking out a window. One plate about 3 cm square on one side of the glass and a matching one on the other side and RF gets through quite efficiently.

    At the point of making this an essay but here is a link to dielectric material:

    http://en.wikipedia.org/wiki/Dielectric
  15. 16 Aug '10 07:41
    Originally posted by sonhouse
    He is talking nonsense. He is referring to the fact that a diode only conducts in one direction and calls that 'dielectric'.

    A dielectric is the insulating layer between capacitors, you have to have an insulator with as high a dielectric constant as possible to make both high voltage and high capacitance. If you have two plates X distance apart, you get ...[text shortened]... say but here is a link to dielectric material:

    http://en.wikipedia.org/wiki/Dielectric
    Thanks for that

    I was rather hoping that it wasn’t true that a material cannot superconduct when you have an AC current because that would be a bit of a pity if it was true I think.