Ignaz Semmelweis tried to convince the medical establishment that washing hand stop’the spread of disease in hospitals. His colleagues responded that doctors are gentlemen and gentlempdo not have dirty hands. Semmelweis was committed to a mental institution soon after and died from an infection as a result of a beoti’he received from institution workers. A few decades later the four humors school of medicine was replaced with diseases caused by microorganisms.
Imagine living at a time when the germ theory of disease wasn’t widely accepted. You might even need to convince people that microbes exist. If they already know about microbes, they might believe that microbes spawn out of thin air through abiogenesis. Previously that word was used when talking about microbes spoiling food whereas nowadays it’s applied to the early stages of the earth.
I don’t know if anecdotal stories are allowed here, but I grew up in Florida before the rise of A/C (no air conditioner in school until 7th year, no house with central air until I was 25. Didn’t really ever sweat until I was 20, though I can now quite normally.
My ex and husband are both from “up north” and both suffer so much more in the heat and the humidity. I suffer so much more in dry and/or cold environments.
Not completely convinced it’s biology - there is a trick to being really still in the shade that seems to sort of cool off/slow down the body. It could be behavior differences. But does seem like they are built differently, thicker and warmer, I am built more spare and cooler.
It is worth dehumidifying a building always though! It’s not good for the materials. Always fighting mildew in the houses before the central air. Everything is so much easier to maintain with the A/C.
you’re seeing elecrochemical corrosion. if you scratch aluminum in such a way that:
oxide layer is removed, and
finely divided copper is deposited, and
oxide layer can’t reform
you’ll see rapid corrosion of aluminum. normally, alumnium doesn’t corrode because of very tight oxide layer. here, oxide layer is removed first by scratching and this also deposits copper in electrical contact with aluminum. then, citrate can bind aluminum removing some of oxide layer, making aluminum more exposed and so more reactive. if you used gallium as heat transfer compound (sp?) then gallium will also disturb oxide layer and make corrosion of aluminum faster. copper elements are in this case actually protected from corrosion (by dissolving aluminum)
This seems brilliant, I wonder what will be the efficiency of such system, it seems like it could almost power itself as long as you supply it with salt water (and have the Fresh water column outlet lower than the inlet). What am I missing?
Hi, could you expand on your question (or questions) in the main post? The more clear your questions are, the easier it’ll be for someone to address them. Thanks!
It looks like you are using this one: ArctiClean 1
Which seems to be specifically made for this application and supposedly consists of “citrus and soy based solvents”. Aluminium is solved by highly acidic (like sulphuric acid) and highly basic (like sodium hydroxide) solutions. Which it really doesn’t sound like until it somehow broke down in a way it got more potent.
Was it maybe a specific thermal paste with a metal like mercury or gallium inside? Supposedly they can quickly dissolve aluminium. Of course, I don’t know what happened but maybe it was dissolved by the cleaning solution and then rapidly reacted with the Aluminium of the heat sink. If so, that would still make me wonder about the bubbling and foaming when the cleaning solution comes in contact with the left overs.
I would assume that nobody makes thermal paste out of anything terribly reactive, but… That .gif looks like something out of a NileRed video.
IIRC, gallium makes aluminum get super brittle, which might cause it to crumble like that; but the foaming makes me think that the heat sink might have managed to oxidize all the way through, and it’s aluminum oxide reacting with the cleaner.
I can’t get your images to load, but to me, a materials chemist, it definitely sounds like you’ve managed to dissolve the aluminium and copper by using an acidic solution. Presumably, the cleaning solution contains some electrolyte that should help dissolve oxides, but if the solution is corrosive enough to oxidise the aluminium and/or copper the electrolyte will make the reaction more aggressive by rapidly dissolving the protective oxide layer as it is formed, such that the aluminium/copper is further corroded.
To be fair, this is just speculation based on what I’ve read here. I could maybe give a better analysis if you let me know what solution you’ve used, and what the heat sink/paste were made of, and if I can get the pictures of the resulting product (“ash”) to load.
Copper metal "dissolves" in nitric acid (HNO3). Actually, the nitrate ion oxidizes the copper metal to copper (II) ion while itself being transformed to NO2 gas in the process; the copper (II) ion then binds to six water molecules.
Your bladder and kidneys need water to function. Initially, your kidneys slow sending water to your bladder which is why your pee turns dark. Then you start losing water in your blood to keep organs functioning but the decrease in blood volume causes your blood pressure to drop. This makes pumping blood increasingly difficult for your heart so your body will start sending less blood to your organs. This starts damaging all your organs and eventually your kidneys stop filtering your blood. Toxins build up in your brain that’s already not getting enough blood and eventually shuts down and you die.
Salts are absolutely necessary for ordinary nerve- and muscular function. If you’ve ever sweated a lot without eating or drinking some salt solution you would notice your muscles start twitching, vibrating and cramping. After a while you can also notice getting light headed and blurry vision.
Source: Been in situations with plenty of water but no salt, and enormous amounts of sweat. Been in the same situations with access to salt for comparison.
My father once went out to do some yard work on a hot summer day, so he made sure to take plenty of water with him. He still ended up collapsing from heat exhaustion. Only reason he didn't have to go to the hospital is because we were able to figure out what was wrong and he still had just enough energy to eat the salty snacks we gave him.
Scary fucking stuff. Keep your electrolytes up, kids.
That’s a very incorrect statement. NaCl, KCl, and MgCl2 are essential for our bodies to function appropriately. If you are working out for an hour or mowing the lawn on a hot day, you are mostly correct. You can replace the lost salt though a balanced diet. If you have sustained sweating, such as when you run a marathon or play a match of football, it can be deadly to not replace these salts.
In the vast majority of cases, people don’t need salt when they exercise. You just described a fringe case that virtually no one experiences. You high school football coach shouldn’t be giving you salt. That could be dangerous. They should be giving you water.
The coach won’t be giving them salt directly, but will always provide a sports drink which contains salts.
Ever watch any sport and a player falls over with a cramp? They have drunk too much water and not enough electrolytes.
Here’s a study from one hospital in Oslo, Norway. Norway is not considered a hot region of the world. Between 2010 and 2015 they treated 31,000 patients in the ER from a population of 135,000 for electrolyte imbalance. That’s roughly 18 patients a day. This is not some sort of fringe case.
Hi there. I’m interested. I’ve also got a science background (life sciences), it’s my job to communicate well, and I’ve been working remotely on a distributed team for years now, so I know how important communication and coordination are. I’d love to help foster an inclusive and informative community, and I can check Lemmy pretty frequently (multiple times a day). I’m okay using Discord. (I’m already on Slack and Telegram basically 24 hours a day, so it’d be great if that were the tool of choice, but Discord is fine, too.)
As water level decreases, the total amount of sodium stays the same. So, essentially it is increasing in concentration. Too much salt interferes with heart cells’ ability to contract together. So less water = more salt = less heart coordination.
Cardiac arrhythmia due to hypernatremia and hypovolumenia can be fatal. There are many changes that occur, but the effect on the heart will kill ya.
Dehydration can lead to death through mechanisms such as organ failure, blood thickening and reduced blood pressure, electrolyte imbalance, brain swelling, shock, and build-up of cellular waste.
Electrolyte imbalances and upset balance of salts and sugar can cause impaired cellular function, heart problems, neurological issues, kidney damage, and shock, ultimately leading to death.
Let me recommend the books by Greg Egan. Essentially, he takes some basic premise of our universe’s physics, twists it around, and then writes novels exploring what living in such a world would be like. Superb. You can check his website for an idea, but don’t be scared by it. He drops all the physics and math in there, but the novels shy away from that and use metaphors where absolutely needed.
/r/askscience was one of the highlights of Reddit - I’d love to help establish a similar community here in /c/askscience. I especially liked that posts and followup questions were rewarded for being inquisitive, and that off topic/inaccurate responses were removed. Posts on topics I’m familiar with were filled with scientific information, and I learned a lot from posts on topics outside my area of expertise (also the ones in my area of expertise, to be honest).
I have a science background (nuclear physics) and lots of experience communicating with remote collaborators. I’m fairly active on lemmy (on another account, I created this one to be my semi-professional one) and would generally have no problem checking the site at least 3 times a day. And I have no issues with mod coordination over Discord.
I check Lemmy about twice a day, work in and foster a collegial environment, and have a background in science. I can’t say I would be intensely active, but currently there is less than 1 post per day here, so even a little would lighten the load.
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