88 points
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I’d like to take this opportunity to highlight a recent discovery that I think should be shouted from every major news outlet. The implications are big, but they’re rather technical and non obvious.

https://www.youtube.com/watch?v=B1PbNTYU0GQ

In short, it turns out water evaporates much faster from to light than heat. Green light with a certain polarization hitting the water surface at a 45 degree angle seems to do best. From the research slides, the effects of polarization and angle might be small. That means green LEDs (which are cheap and very efficient, but wouldn’t be polarized on their own) can evaporate lots of water. Something like 4 times the amount we would get from using the same amount of energy to heat it up. This is being called the photomolecular effect.

This fills in a big gap in our climate models. There have been measurements done on clouds that show water was evaporating much faster than theory would predict. I’m not clear on if it would make the results more pessimistic or not. My guess is that more clouds in the model increase the albedo of the Earth, thus reflecting more light back into space, and the resulting temperature should be lower. But I’ll hold off on strong opinions until the models get updated.

The other big thing is desalination. Most desalination plants don’t use thermal evaporation because it’s too energy intensive. They use reverse osmosis. The photomolecular effect brings up the possibility of an even more efficient solution to drinking water problems.

I haven’t seen academic research into this yet, but I also wonder about the implications for lithium extraction from sea water (and pretty much any other sources, really). Lithium is basically one of the salts you remove during the desalination process, so the photomolecular effect potentially makes sea water extraction cheaper. Lithium from sea water is an indefinite resource–there’s more there than we would know what to do with.

Edit: actually, scratch the desalination aspects.

So thermal distillation is almost an order of magnitude behind, and the 4 fold improvement doesn’t fully close that gap. In fact, it’s worse than that. The multi-stage plant works by recovering heat when the distilled water is recondensed. Merely heating water to do this would take 626 kWh per m3. That’s more than two orders of magnitude, and since we can’t benefit from a multistage setup to recover heat when using the photomolecular effect, it’s going to be a 4 fold improvement over that very high number.

Still, very big news for improving our climate models.

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7 points

You can accelerate evaporation 1000s of times by aerosilizing/spraying water.

No lazers needed.

https://www.youtube.com/watch?v=xGi_JetNWWs&t=3

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7 points

You’re not desalinating aerosilized water. All the salt comes with.

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5 points

Yeah, you can buy humidifiers that work by aerosolizing water, and they’re very energy efficient, but the problem is any bacteria that grows in it will just get spread all over your house if you don’t clean it frequently.

The ones that operate by boiling water are definitely a lot better for health reasons, but it’s a trade-off.

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3 points

Thanks for taking the time to explain that so clearly! It’s really interesting.

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55 points

If this type of basic science research interests you, in the US there is a federal agency dedicated to this pursuit; the National Science Foundation (www.nsf.gov)

95% of its annual budget goes out the door in the form of research grants to colleges, small businesses and individuals. Most of the research has no immediate application but has lead to some very exciting discoveries. The biggest in the recent past was that orange donut picture of a black hole that was everywhere. ( https://new.nsf.gov/blackholes/how-are-black-holes-studied#eht)

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22 points

NSF pays my salary. They are goated with the sauce

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11 points

Fun fact, the NSF was founded after WWII to fund basic science just in case it found something with applications.

Unfortunately, the driving force behind it was the DOD, whose idea was that if even 1% of the work funded eventually became relevant to weapons research, then it would be “worth it”. But hey, at least basic science got funded.

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4 points

Now NSF funds all branches of science excluding defense and most medical. Those are DOD and NIH for the most part.

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3 points

Yeah, and in the last couple decades the NIH and NSF have become more applications-focused. If you can’t show a commercial application for your basic research. It’s less likely to get funded. Now, the DOD is the easiest way to get true basic research funded, which isn’t ideal; only basic research which the DOD thinks is important will get funded.

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43 points

Also a ton of discoveries and inventions are on accident while looking for completely different things.

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14 points
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One of my favourite stories is the accidental discovery of synthetic purple dye. IIRC there was a chemist researching something completely unrelated and when he disposed some assorted chemicals down a sink he noticed they turned purple.

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15 points
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This is basically the reason we have artificial sweeteners, too.

Some dude was trying to make/do something, and labs were sort of “lol everything is safe” back then so he like… had a sandwich… and noticed it was sweet… so he just sort of tasted all the stuff he was working with and found aspartame. (I believe it was aspartame)

I believe the same is true for fabreeze, the underlying chemical mechanism was an accidental discovery because the researcher’s wife noticed he didn’t smell of cigarettes. It never caught on tho because it, naturally, has no smell, and you become blind to smells you are constantly exposed to, so until they added perfumes (fabreeze as we know it today), even tho it worked, nobody cared to use it. I wish I could actually find it unscented… the scented shit stinks and gives me headaches.

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0 points

It’s Febreeze. I know I’m being a stupid spelling nazi but I swear everyone spells it wrong and for some reason it drives me crazy. I have similar feelings about Scünci from my youth, but that battle has long been lost.

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4 points

Also, I believe the rubber was discovered by a scientist accidentally dropping a mixture of a bunch of materials like resin onto a burner, which made it volcanize (man I hope I got the word right) into a layer of rubber in the middle

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6 points

Vulcanize, haha. All good, though!

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33 points

Those discoveries benefit all of us in turn. Microwave ovens, digital cameras, water filters, freeze drying, memory foam, and many other inventions we use daily were created by funding scientists to collaboratively solve problems unique to space.

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9 points
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And literally all of modern electronics works in no small part because of our understanding of calculus, which, in turn, wouldn’t exist if we didn’t ponder the concepts of infinities in mathematics. Which might seem like one of the most removed from reality ideas, but here we are

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25 points
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Thank you. As a layman, I don’t always see the bigger picture. I cannot recall the specifics right meow, but there was some sciency stuff I read about the other day and I was questioning why they would spend money on that, when there are other things to figure out. Maybe one day their results will help with something else.

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8 points

I read this post and my first thought was “oh, it’s like how fans post videos of fun glitches in video games and then speedrunners sometimes end up finding a use for them in order to beat the game faster.”

Scientific progress is just glitch-hunting and speed/challenge-running.

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