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The first room-temperature ambient-pressure superconductor?

arxiv.org

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Re: The first room-temperature ambient-pressure superconductor?

#411

Post by mildchalupa »

scarmig wrote: post #187
amluto wrote: post #145

Earlier quoted context omitted.

The actual picture of (poor) levitation in the paper you linked is pretty compelling. This isn’t a complex, noisy measurement showing something that’s related to superconductivity — this is a magnet and a supposed superconductor repelling each other. As far as I know, that’s possible with permanent magnets (and it would be weird, but not impossible, if the group instead synthesized a novel ferromagnet and didn’t noti…

Their other data doesn't line up with ferromagnetism, though. It's either the real thing or a big fraud. Guess we'll find out soon enough. ETA: the video referenced is apparently available at https://www.youtube.com/watch?v=EtVjGWpbE7k . Interestingly, posted on Feb 26, 2023.

Electromagnetic solenoid designer here...

Copper and a magnet can certainly interact. Drop a magnet through a copper pipe and the eddy currents will induce a field that's opposed to the magnet causing a damping effect. Maybe something like this is going on where movement of the magnetic field is inducing an opposed magnetic field in the copper, and thus interacting.

Anyhow it will be interesting. if It can generate a field of 1.5-2 Tesla you could have more efficient solenoids and probably motors.

Re: The first room-temperature ambient-pressure superconductor?

#412

Post by floxy »

XorNot wrote: post #246
swagmoney1606 wrote: post #207

Earlier quoted context omitted.

Video: https://www.youtube.com/watch?v=EtVjGWpbE7k I really need someone to bring me down a notch. This is too exciting!

That video isn't very convincing. The usual test is that the material can float above the magnet.

This is the better video:

https://sciencecast.org/casts/suc384jly50n

Re: The first room-temperature ambient-pressure superconductor?

#413

Post by skykooler »

marcosdumay wrote: post #245
alexb_ wrote: post #231

Earlier quoted context omitted.

Just give it to me straight - when will the levitation give us hoverboards?

As long as you only want them to hover over a magnet...

I wonder how big of a superconductor you'd need to use Earth's magnetic field.

Re: The first room-temperature ambient-pressure superconductor?

#414

Post by xsmasher »

allenrb wrote: post #4

If this were true, I would’ve expected to see it on the front page of the New York Times, not hiding in a scientific journal. Color me skeptical, with a hint of optimism.

Isn't that what Pons and Fleischmann did, calling a press conference? Going through review and publication first seems more prudent.

Re: The first room-temperature ambient-pressure superconductor?

#415

Post by MisterTea »

foxhill wrote: post #6

big if true. far from a chemistry expert here, but synthesis looks basically trivial (if you consider 10e-5 torr vacuum to be trivial), and the materials are readily available. hell, from the instructions alone i could probably make it at home. i mean the search space is unfathomably large, so i suppose it’s possible that something like this exists, but the paper quality itself doesn’t.. spark joy? :) i’ll maintain a…

> if you consider 10e-5 torr vacuum to be trivial

Its not hard to achieve at all. Electron beam welders at work have 10E-6/10E-7 in the E-gun chamber all day long held by a little turbo or diffusion pump. The chambers aren't made from anything exotic just stainless steel and/or aluminum with viton o-rings.

Re: The first room-temperature ambient-pressure superconductor?

#416

Post by gus_massa »

floxy wrote: post #127
lokl wrote: post #19

Will they invite a wide range of experts to publicly test their material?

Let's hope so. The easiest way to convince the world that you have a room temperature superconductor is to make up a big batch of samples and offer to distribute them to national labs for testing. First test, does it levitate a small permanent magnet, demonstrating diamagnetism?

They wrote the recipe. It looks like it's easier (for people that has a similar lab) to make your own instead of filling all the import reports to get one.

Some superconductors get destroyed by humidity, so it may be difficult to ship them.

If nobody can reproduce them, then they can send samples or travel the word making samples on site, or receive researches to train them.

The good part of publishing the recipe, is that other people can make small variations. If this is true, there is just now a big race to get a higher record temperature.

Re: The first room-temperature ambient-pressure superconductor?

#417

Post by p1mrx »

JumpCrisscross wrote: post #354
post-it wrote: post #345

Earlier quoted context omitted.

They could only cause problems solvable by more superconducting railguns, so they're a net zero at worst.

> could only cause problems solvable by more superconducting railguns If the projectile is ferromagnetic, or potentially even just diamagnetic, a defense system involving shaped ultra-high intensity magnetic fields becomes conceivable.

When you activate the city shield, all your buildings become projectiles.

Re: The first room-temperature ambient-pressure superconductor?

#418

Post by jacquesm »

marcosdumay wrote: post #406
jacquesm wrote: post #318

Earlier quoted context omitted.

This isn't even wrong. A voltage can be present without a current flowing. Touch any live wire to get an instant demonstration that there indeed was a voltage present even if no current was flowing. Not because the wire is an insulator but because it wasn't at that point in time conducting any current. Your finger (also not an insulator) closing the circuit however and then allowed current to flow.

Ouch, you need to take another look at that. The definition of an insulator is a material that holds (up to some amount of) voltage without electrical currents appearing. Your example needs two wires. And the wires themselves don't have any voltage. All of the voltage is between them, and is only there because they are insulated from each other.

No, the definition of an insulator is a material that doesn't have the ability to carry current because it has no free electrons.

You are conflating 'insulated' and 'insulator'.

Re: The first room-temperature ambient-pressure superconductor?

#419

Post by floxy »

pengaru wrote: post #359
swamp40 wrote: post #357

Earlier quoted context omitted.

The video text says: "The sample was thermally deposited on a copper plate." The video headline says: "Magnetic Property Test of LK-99 Film". That's how copper acts with a moving super magnet[0], so the video doesn't really show anything. [0] https://youtu.be/KrH3t1H6fOc?t=50

The video shows that this is all bollocks

This is the better video:

https://sciencecast.org/casts/suc384jly50n

Re: The first room-temperature ambient-pressure superconductor?

#420

Post by MisterTea »

foxhill wrote: post #6

big if true. far from a chemistry expert here, but synthesis looks basically trivial (if you consider 10e-5 torr vacuum to be trivial), and the materials are readily available. hell, from the instructions alone i could probably make it at home. i mean the search space is unfathomably large, so i suppose it’s possible that something like this exists, but the paper quality itself doesn’t.. spark joy? :) i’ll maintain a…

> if you consider 10e-5 torr vacuum to be trivial

Its not hard to achieve at all. Electron beam welders at work have 1E-6/1E-7 in the E-gun chamber all day long held by a little turbo or diffusion pump. The chambers aren't made from anything exotic just stainless steel and/or aluminum with viton o-rings.

My little e-gun experiments are all done with a Alcatel Pascal 2008 and I can achieve ~3E-3 with just that pump. I'm building a bigger system with a VHS4 diffusion pump w/cold trap that should get me into -6 territory easily.

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