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The first room-temperature ambient-pressure superconductor?

arxiv.org

741–750 of 906 posts

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

#741
post #735

Earlier quoted context omitted.

The reason is pretty obvious and doesn't require any kind of conspiracy. Nuclear can be done safely, we know this, because every single time there has been an accident it's because an operator did something wrong. The problem is that nobody has yet designed a reactor that a sufficiently amoral operator could not make unsafe. Even if you have completely automatic and passive safety features, a bad operator could disab…

> The problem is that nobody has yet designed a reactor that a sufficiently amoral operator could not make unsafe. That's not true. There are many designs (e.g. molten salt reactors) where the operator cannot do anything to cause the reactor to fail. The reason we're stuck with water reactors is mainly politics, and somewhat laziness.

Molten salt reactors manage to be expensive for perfectly normal engineering reasons though. The salt is highly corrosive, meaning you need tons and tons of extremely expensive piping that can withstand extremely high temperatures and extremely corrosive environments.

There's a reason none of _those_ have been built either. No amount of red tape would make them unviably expensive if the end product was cheap enough to run, but it isn't.

Also I should mention, part of what makes them passively safe is there is a plug at the bottom that melts if the reactor overheats. This is easy to bypass, put something over the plug that won't melt.

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

#742

Earlier quoted context omitted.

Yes lead in the ground isn't all that scary. Lead in your body is a concern. So don't blow lead smoke over your neighbors house.

This post is what happens when chemistry sets don't contain anything more hazardous or interesting than marshmallows.

I think it's more that a generation of people grew up with lead paint and that decreased the average IQ so much that you have people suggesting that lead smoke is harmless.

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

#743

Earlier quoted context omitted.

From my understanding it is superconductive up to that temp. So, superconductive at room temp and even further.

That makes me even more sceptical. In recent years confirmed discovery of superconducting materials have gone from working at best up to ~100K below room temperature to at best a few 10s of K below. To jump to a material that claims to exhibit superconductivity as far as >100K above room temperature, at ambient pressure too, is an extraordinary claim and so needs to be presented with extraordinary evidence.

It's not out of line with previous the previous jump: the difference between the originally known superconductors and 'high temperature' superconductors was similarly large. If it is a novel mechanism allowing for it then we would not expect that the threshold would necessarily wind up close to room temperature (TBH, I this makes me think it is less likely to be fraud: I think a fraud would temper expectations by claiming it barely works at room temperature). I do agree it needs backing up, though, it could still be an error or more savvy/brazen fraud.

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

#744
post #377

Earlier quoted context omitted.

Does anyone in the twin cities area want to pair up and try to make this? Might be a fun group project.

I’d be down. Shoot me an email: hn@valine.io

Also down. Will email you

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

#745
post #723

Read this comment thread from SC researchers: https://www.reddit.com/r/worldnews/comments/159g2k4/comment/... Lots of problems with the paper, they claim. It is not up to the standards of current SC research. One of them says Dias's work shows more merit than this.

All valid points but just below that comment someone asked if he/she was reading the new paper (apparently there's an older paper), he/she didn't respond/haven't responded yet.

They did now – https://old.reddit.com/r/worldnews/comments/159g2k4/roomtemp...

Either way we should hear from people trying to replicate it soon.

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

#746

This is an unreviewed preprint coming out of South Korea. If it’s reproducible it would be the biggest scientific discovery of the last hundred years. It will literally reshape the world. However, the most likely thing is they made a mistake and the paper will be withdrawn. But imagine if it’s true.

Scientific discoveries since 1923 include quantum mechanics, just for the first 1920s discovery to come to mind. Still it'd be a prime new part of "living in the sci-fi future" for me.

Also antibiotics, DNA, personal computers

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

#747
post #276

Earlier quoted context omitted.

Reminds of "command line is faster than GUI" folks who get timed doing every task slower. "But it feels faster!"

Every task? If I want to rename all of the .pdf files in the folder to .avi I would just do it in the command line Or would you rather have me google a GUI that lets me "quickly rename" and download a few programs that have this capability? Or do a few hundred files by hand?

There are these things called programming/scripting languages, look it up. python for example. And you end up with very short and simple - and most importantly - human readable programms instead of cryptic Unix two letter commands with bunch of arcane single letter flags and other legacy pdp11 nonsense from 1970ties

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

#748

Guys, even if everything in this paper is true, the material as it is might have limited applications. From what they show, the critical field and critical current seem very low. 2500 Oe is like 0.25 Tesla. Even REBCO at 77K is >1T. And 2500 Oe is not even at critical temperature but much lower. From skimming through the article I couldn't find the sample size of the current measurement to get the critical current de…

You can improve the current density a lot if you can make a single crystal, or at least make your crystal grains larger. Impure superconductor samples often come out as a spongy mixture of superconducting and non-superconducting bits, the critical current is limited because less then 25% of the cross section is actually carrying current. When I was DIYing YBCO this is what happened most of the time. Every now and the…

Are we talking the cool crystal selection spirals like RR et al use to make monocrystaline turbine blades? https://www.americanscientist.org/article/each-blade-a-singl...

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

#749

Earlier quoted context omitted.

How would superconductivity help to reverse climate change? Honest question.

I believe the biggest envisioned possibility is superconducting power lines. Those would allow long-distance power transfer with minimal losses. In the most idealistic scenario, you could imagine a belt of solar power plants around the globe connected by superconducting power lines, providing solar power 24h a day. Of course, there are huge hurdles to such a project even if we did have the superconducting lines, but…

>In the most idealistic scenario, you could imagine a belt of solar power plants around the globe connected by superconducting power lines

There's no technical impairment for doing this with current tech, and it's not clear the new tech is cheaper.

Power lines are already very efficient, especially the long-distance ones. We would save a bit on converting from HVDC to AC but that's also very efficient.

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

#750

Earlier quoted context omitted.

> more about producing toxic waste Compared to refining traditional conductors and recycling/disposing of used electronics? > you still have to use lead-free solder One, fumes. Two, people touch their solder and then grab a cookie. We're premature. The results need to be proven. But the benefits of RTP superconductors is mindblowingly high enough that risks from lead contamination (far from a novel problem, I might a…

> One, fumes. It's trivial to experimentally demonstrate that solder fume contains almost no lead, the quantity is negligible. Claiming the contrary is the electronics equivalent of saying HTML is a programming language. Please don't do that again. The fume is indeed toxic, but it's due to the VOCs from the flux core, not the lead in the alloy. A more solid (no pun intended) argument can be the hazards of debris. Fur…

> Solder paste and a reflow oven are required for prototyping any circuit boards with surface-mount components (SMT) - basically any modern circuit board today.

This is incorrect. You can easily do small scale work with almost all SMT components without solder paste. Solder paste is required for automated assembly processes. But almost anything done by hand can also be done with conventional solder.

Source: I worked as an electronics designer for a few years, and assembled prototypes and small production batches by hand with SMT parts (0603's, TTSOPS, etc) every day.

The one exception is BGA devices, because the solder pads are underneath the device. But doing those by hand requires precise alignment that is difficult enough that few people do it. Also, for smaller BGA devices with fewer pins, skilled operators can still solder them in place with a heat gun by covering the pads with solder and flux and just melting them into place.

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