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Successful room temperature ambient-pressure magnetic levitation of LK-99

arxiv.org

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Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#741

Post by fellowmartian »

ricardobeat wrote: post #734
fellowmartian wrote: post #679

Earlier quoted context omitted.

Full body MRI scans are only expensive in the West, outside the west you can get one done for $250. This is a labor and regulatory capture problem and not a technology problem and will not be affected in any meaningful way by better superconductors.

$250 is a ton of money outside ”the west” (I assume you mean US/Europe/Aus). It’s roughly the minimum wage in Brazil.

I know, but my point is that the price doesn’t scale with machine and helium costs, but with labor costs and the level of insurance racket a particular country has. Obviously it’d be great if we didn’t require helium supply chains to make medical scans, but unfortunately we can’t fix everything with technology alone.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#742

Post by elfbargpt »

EDIT: This is probably fake. The account was just created and can't find any info online. Also the pellet returns to its starting position for some reason.

Just saw another unconfirmed replication here: https://twitter.com/instsondaw/status/1687433935012139008?s=...

Found their process really fascinating, apparently they create L-99 powder, sort it by meissner effect, then press the "high meissner effect" powder together

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#743

Post by [deleted] »

mk_stjames wrote: post #735

This is obviously a quickly produced paper to get the finding out but.... I find there to be so much missing and so many things poorly worded or posed about their process that would have taken zero time to expound upon, it's infuriating. "All the reactions are carried out under 10^-2 Pa" OK, I know they mean 10^-2 of vacuum. But why not say that? "10^-2 Pa" isn't enough. Was this a full vacuum oven? Done in sealed qu…

[deleted]

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#744

Post by soligern »

elfbargpt wrote: post #742

EDIT: This is probably fake. The account was just created and can't find any info online. Also the pellet returns to its starting position for some reason. Just saw another unconfirmed replication here: https://twitter.com/instsondaw/status/1687433935012139008?s=... Found their process really fascinating, apparently they create L-99 powder, sort it by meissner effect, then press the "high meissner effect" powder toge…

Interesting. So this doesn’t exhibit flux pinning then.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#745

Post by dmitrybrant »

Can I ask why we're using a special definition of "levitation" that doesn't really mean levitation? I'm finding it very annoying to click headlines that say "Levitation of LK-99!", and... ohh it's still standing on one end.

I'm sure this is a promising discovery and everything, but saying "levitation" at this stage is very forward-looking, and for me - a bit cynicism-inducing.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#746

Post by appplication »

drtgh wrote: post #610
appplication wrote: post #205

Earlier quoted context omitted.

Do you mean replacement of chemical batteries for superconducting ones?

if he means that, I do not see it happening so easily, Energy storage in a superconductor is done in the form of magnetic field, a superconducting induction coil (SMES), whose density of energy storage per kilogram is highly inferior to a capacitor and a supercapacitor, which stores energy in the form electric fields, and whose density of energy storage per Kg in turn is very inferior to chemical batteries. The magne…

This is consistent with my understanding as well. I don’t see instant battery charge being something that this enables. Current battery charge rates are limited by battery structure degrading more rapidly at high charge/discharge rates, so this wouldn’t really have any direct effect.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#747

Post by Workaccount2 »

XorNot wrote: post #408
hwillis wrote: post #383

Earlier quoted context omitted.

You can't get CT scans very often, because they hit you with large doses of ionizing radiation. Ultrasounds are low-resolution spotlights; you shine them at a particular spot to diagnose something specific. With this you could get an MRI at your annual checkup. You could diagnose all number of diseases like that, not to mention 95% of cancers. Each year your scan is automatically compared to the previous year, and an…

> We might eventually transition away from AC power entirely. This is actually a really good point I hadn't fully considered, but it's right: the primary reason we use high voltage anywhere is because it minimizes resistive losses (and the reason we use AC is because it's easy to transform between voltages). But most of the stuff in my home doesn't need high voltage - it's all running at 5V or 12V. Or it's a motor wh…

We use AC because changing voltage levels with it is extremely simple and efficient compared to DC.

In fact the only (practical) way to convert DC voltage levels is to convert to AC, do the level conversion, then convert back to DC.

Believe it or not, DC already is more efficient for energy transfer and why there are already DC high voltage transmission lines. You don't have to deal with reactive parasitics.

But again the killer is that AC voltages are so easy to switch and can by done with >99% efficiency.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#749

Post by John23832 »

dmitrybrant wrote: post #745

Can I ask why we're using a special definition of "levitation" that doesn't really mean levitation? I'm finding it very annoying to click headlines that say "Levitation of LK-99!", and... ohh it's still standing on one end. I'm sure this is a promising discovery and everything, but saying "levitation" at this stage is very forward-looking, and for me - a bit cynicism-inducing.

I would assume that this is because of the lack of purification of the samples.

A fully pure sample would probably fully levitate. Given the rush to recreate and lack of purity, if a portion levitates (causing standing on one end) you could assume a pure sample would fully levitate.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#750

Post by aqme28 »

hwillis wrote: post #383
nocoder wrote: post #139

I get the idea of superconductivity at room temperature in theory. But I don't have enough knowledge to understand in real terms, how will the world change if this is true?

You can't get CT scans very often, because they hit you with large doses of ionizing radiation. Ultrasounds are low-resolution spotlights; you shine them at a particular spot to diagnose something specific. With this you could get an MRI at your annual checkup. You could diagnose all number of diseases like that, not to mention 95% of cancers. Each year your scan is automatically compared to the previous year, and an…

> Fires, particularly house fires would become less common as wires simply stop conducting when they are overloaded.

I don't know enough about how this material behaves, but a superconductor "quench"* can be pretty catastrophic. I could see a room temperature superconductor battery causing fires from a quench.

*: https://en.wikipedia.org/wiki/Superconducting_magnet#Magnet_...

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