Josu
Emperor
TIL that first basque mythology book was written by an anglican clergyman
Today I Learned #3: There's a wiki for everything!
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TBH, this is not exactly how I imagine a centrifuge.
Yeah, that is why I thought it worth posting. I guess they are spinning metal tubes full of uranium hexafluoride, with the lightest fraction of one feeding into the next.
Spoiler Diagram :
Somewhat related: TIL:
https://en.wikipedia.org/wiki/Plutonium
Sounds in hindsight obvious, but I never realized.
https://en.wikipedia.org/wiki/Plutonium
Sounds in hindsight obvious, but I never realized.
Yeah, that is why I thought it worth posting. I guess they are spinning metal tubes full of uranium hexafluoride, with the lightest fraction of one feeding into the next.
Spoiler Diagram :
The bottom is heated a little bit to get that convection circulation you see.
I guess:
The heavier U-238HexaFluoride gas going to the sides because of centrifugal forces, but also caught in that slow speed convection circulation going down along the sides, where it is tapped into the waste pipe.
IDK if the U-235 fraction is tapped (at the top outside that convection current) continuously... or intermittent (with the valve of the waste closed).
That Iran has this tech is a big shame for NL
"He was a nice man," says Frits Veerman. In the 1970s he worked as a technician in the underground bunker of Stork's Physical-Dynamic Research Laboratory (FDO) in Amsterdam. "There were about six ultracentrifuges. Test installations. "Veerman liked the fine mechanical work. But into the bunker every day, phew. "Then I was asked if I wanted to build an audiovisual department. I took pictures. "Veerman was in the office of Abdul Qadir Khan. "We sat opposite each other for about a year and a half." The two also played tennis together. Of course, Khan was not known at the time as the father of the Pakistani nuclear bomb. And he had not yet sold his knowledge to North Korea or Iran. He was still busy spying.
tjs282
Stone \ Cold / Fish
You mean the gradient?
The illustration shows the result of two acceleration forces acting at right-angles: the centripetal force (something like 100,000 x g, IIRC) tends to fling the U238 outwards faster than the U235, producing your 'expected' gradient — but there is also a thermal gradient applied which tends to cause the (lower density) U235 to rise vertically (up the centre of the centrifuge, because that's where it's concentrated) due to its marginally greater buoyancy, while the (higher density) U238 sinks down the outside, eventually producing the convection current shown (especially once the takeoffs are opened).
The vertical separative effect would still be minimal compared to the centripetal force applied, which is why (as you noted) multiple centrifuges need to be used in series for effective enrichment to take place: the 'product stream' from the first-stage centrifuge(s) will inevitably still have some level of U238 contamination, but by feeding that stream through several additional centrifugation steps, the proportion of contamination can be reduced by orders of magnitude at each stage.
As shown by the photo you posted, real gas-centrifuges are also a lot taller/thinner than shown in that diagram, so the convection effect has more vertical space to act. But it also makes the things much more rotationally unstable (the cylinder spins so fast that it also gets distorted), which is why the Stuxnet virus was — allegedly! — able to do significant damage to the Iranian uranium-enrichment facility.
EgonSpengler
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Gustav III of Sweden would have hated to read that.
In fact, it appears that "coffee" was the cause of his death in that his assassins loved the stuff and opposed his ban.
Shame they didn't know about the other Kuiper Belt mini-planets at the time when the rest of the post-uranium elements were being named. Try spelling "quaoaronium" right every single time.
TIL that the TUC are holding an online rally for a "Workers Budget". I am sure it is a good cause and all, but I am not at all sure about what an online rally can do. I guess I shall attend, as it does not actually require me to put any effort in.
TIL that you will do well to throw a rock at armed warriors who are born from the ground after you sow a dragon's teeth in it. https://en.wikipedia.org/wiki/Spartoi
Adrian Carton de Wiart was an absolute legend. His exploits in WWI had already made him famous, and was still on active service in WWII. Once, when attempting to escape from Allied capture, he spent eight days disguised as an Italian peasant (he was in northern Italy, could not speak Italian, and was 61 years old, with an eye patch, one empty sleeve and multiple injuries and scars).
TIL that as well as everything else, fesesbook is helping deforest the Amazon:
Parts of Brazil's Amazon rainforest are being illegally sold on Facebook, the BBC has discovered.
The protected areas include national forests and land reserved for indigenous peoples.
Facebook said it was "ready to work with local authorities", but indicated it would not take independent action of its own to halt the trade.
Anyone can find the illegally invaded plots by typing the Portuguese equivalents for search terms like "forest", "native jungle" and "timber" into Facebook Marketplace's search tool, and picking one of the Amazonian states as the location.
Deforestation in the Brazilian Amazon is at a 10-year high, and Facebook's Marketplace has become a go-to site for sellers like Fabricio Guimarães, who was filmed by a hidden camera.
"There's no risk of an inspection by state agents here," he said as he walked through a patch of rainforest he had burnt to the ground.
With the land illegally cleared and ready for farming, he had tripled his initial asking price to $35,000 (£25,000).
Fabricio is not a farmer. He has steady middle-class job in a city, and views the rainforest as being an investment opportunity.
Mr Alves revealed he was working with others to lobby politicians to help them legally own stolen land.
"I'll tell you the truth: if this is not solved with [President] Bolsonaro there, it won't be solved anymore," he said of the current government.
A common strategy is to deforest the land and then plead with politicians to abolish its protected status, on the basis it no longer serves its original purpose.
The land grabbers can then officially buy the plots from the government, thereby legalising their claims.
The protected areas include national forests and land reserved for indigenous peoples.
Facebook said it was "ready to work with local authorities", but indicated it would not take independent action of its own to halt the trade.
Anyone can find the illegally invaded plots by typing the Portuguese equivalents for search terms like "forest", "native jungle" and "timber" into Facebook Marketplace's search tool, and picking one of the Amazonian states as the location.
Deforestation in the Brazilian Amazon is at a 10-year high, and Facebook's Marketplace has become a go-to site for sellers like Fabricio Guimarães, who was filmed by a hidden camera.
"There's no risk of an inspection by state agents here," he said as he walked through a patch of rainforest he had burnt to the ground.
With the land illegally cleared and ready for farming, he had tripled his initial asking price to $35,000 (£25,000).
Fabricio is not a farmer. He has steady middle-class job in a city, and views the rainforest as being an investment opportunity.
Mr Alves revealed he was working with others to lobby politicians to help them legally own stolen land.
"I'll tell you the truth: if this is not solved with [President] Bolsonaro there, it won't be solved anymore," he said of the current government.
A common strategy is to deforest the land and then plead with politicians to abolish its protected status, on the basis it no longer serves its original purpose.
The land grabbers can then officially buy the plots from the government, thereby legalising their claims.
TIL: The Power of The Wandering Mind
THERE’S ONLY ONE way to write: Just do it. But there seem to be a million ways not to write. I sit down to work on my column, write a sentence and—ping!—there’s a text with a video of my new baby grandson. One more sentence and I start ruminating about the latest virus variant, triggering a bout of obsessive Covid worry. Cut it out! I tell myself, and write one more sentence, and then I’m staring blankly out the window, my mind wandering: What was it with that weird movie last night? Should I make chicken pilaf or lamb tagine for dinner?
These different kinds of thinking are the subject of a paper I co-authored recently in the journal PNAS, which has an interesting back story. Zachary Irving is a brilliant young philosopher now at the University of Virginia, well-trained—as philosophers have to be—at thinking about thinking. He is especially interested in the kind of unconstrained thought we have when our mind wanders. Is mind-wandering really distinct from other kinds of thought, like simple distraction or obsessive rumination? And why do we do it so much?
Young children daydream a lot, so Zach came to visit my lab at Berkeley, where we study children’s thinking. Neuroscience has mainly focused on goal-directed, task-oriented thinking, but what is your brain doing when your mind wanders? To answer that question, we worked with Julia Kam, now at the University of Calgary, and Robert Knight to design an experiment that involved giving 45 people a tedious but demanding task: pressing an arrow when a cue appeared on the screen. The participants did this more than 800 times for 40 minutes, and at random intervals we asked them to report what they were thinking. Were they thinking about the task or something else? Were they obsessing about a single topic or were their minds freely wandering?
Meanwhile, the participants’ brain waves were being measured with electroencephalography or EEG. The study found that different types of thinking correspond to different brain wave patterns. Like earlier researchers, we found that brain waves are different when you pay attention to a task and when you get distracted. But we found that different types of distraction also have different brain signatures. We compared what happens when your mind is captured by an internal obsession like worrying about Covid, and what happens when it wanders freely.
When your mind wanders there’s a distinctive increase in a measure called frontal alpha power, which captures a particular type of wave coming from the frontal lobe of the brain. That’s especially interesting because the same brain waves are associated with creative thinking. People show more frontal alpha power when they are solving a task that requires creativity, and more creative people show more of this kind of activation than less creative ones. One study even showed that stimulating frontal alpha led to better performance on a creativity task.
TOMASZ WALENTA
There was also more variability in those frontal alpha waves when thoughts wandered than when they were focused. The brain patterns went up and down more during those thoughts, just like the thoughts themselves. We puritanically tend to value task-related thinking above everything else. But these results suggest that simply letting your mind wander, the way kids do, has merits too. My wandering mind made this column harder to write. But maybe it came out better as a result.
Berzerker
Deity
TIL I'm not really a Stevie Nicks fan... I just watched her 24 karat gold concert on PBS and her voice just doesn't do anything for me. Too monotone and little range.
given the antiquity and uniqueness of the Basques I'd be interested in their mythology
given the antiquity and uniqueness of the Basques I'd be interested in their mythology
Some of my best story ideas come from letting my mind wander. Lines of dialogue and ideas for new plot branches seem to come out of nowhere, brought on by some random thought.
I wonder how many people in that study also had music running through their minds, constantly in the background. I don't mean whole, entire songs, but just music.
Josu
Emperor
We indeed have our peculiarities but almost everything which has arrived to our times is basque details added to a Roman/Greek or western european myth.
Our Tartalo is a Cyclop, we also have Lamias, and our Galtzagorri is a benebolent imp.
Our Basajaun has similarities with Roman Silvanus and some historians claim that our deity Mari is Roman Magna Mater.
Myths have always been stories that explain things that our ancestors could not understood. Basque trandition has been told mainly oral, during middle ages cultured people in basque country were people whose family had enough money to pay a classic education, which included latin and greek. These people read about these myths and told to peasents, who included them in their own stories.
BTW, TIL I learned that Yerushalayim shel zahav's melody is vaguely based in a basque lullaby, this is a popular Israeli song, which I knew from Schidler list's OST
r16
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last weekend or so ... Now , my horizon from the house has a lot of mountains , green , grey , maybe blue all mixing up and you can rarely see the lay of the land , the contours , stuff . Except sunlight in some angle and some clouds create shadows , to let me notice like for the first timd that closest big hill has a flat section and the building there must be the small palace they built for some Ottoman Sultan who had just one tour of Anatolia in mid or late 19th Century and spent just one night there ... Possibly because they didn't have any place fit for a Sultan in the big city .
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