Today I Learned

  • Thread starter Greg Bernhardt
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In summary: Today I learned that Lagrange was Italian and that he lamented the execution of Lavoisier in France during the French Revolution with the quote:"It took them only an instant to cut off this head and a hundred years might not suffice to reproduce it's...brains."
  • #2,836
TIL that Switzerland has a real good law: What once is forest, has to stay forest!
 
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  • #2,837
In Oregon, its more like:
what was once forest, if now it is made not forest,
replant it to make it forest again (for a while).

Not so good for the larger/older trees.
 
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BillTre said:
In Oregon, its more like:
what was once forest, if now it is made not forest,
replant it to make it forest again (for a while).

Not so good for the larger/older trees.
The swiss don't do it for nature alone. The fact is, they master elementary arithmetic!

They save more than 4 billion CHF per year: less avalanches, mud slides, floods, etc.
 
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fresh_42 said:
They save more than 4 billion CHF per year: less avalanches, mud slides, floods, etc.
Trees prevent Congestive Heart Failure ?
 
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  • #2,840
fresh_42 said:
TIL that Switzerland has a real good law: What once is forest, has to stay forest!
The problem with that is in some places trees grow really fast, and places that weren't forest, become forest and can't be cut back.. I know this from the Ticin, where there are a lot of little cottages on acreages that got abandoned
 
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In an effort to "Go Green" South Korea cut down 4400 hectare of forest (2 million trees) to make way for solar farms
 
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  • #2,842
Today I learned that South Korea probably looks pretty green.

2019.07.28.S.Korea.solar.vs.forest.png

South Korea land use[ref: wiki, of course]
Arable land: 15.3%​
Permanent crops: 2.2%​
Permanent pasture: 0.6%​
Forest: 63.9%​
Other: 18.0%​
 
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  • #2,843
TIL to experience several levels and flavors of sadness; some quite sweet.
 
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Klystron said:
TIL to experience several levels and flavors of sadness; some quite sweet.

I don't like sadness. :frown:
 
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  • #2,845
Klystron said:
TIL to experience several levels and flavors of sadness; some quite sweet.
Drakkith said:
I don't like sadness. :frown:
Correction: Bitter sweet. 🤐 Dark chocolate bitter. Yet sweet, like birdsong. 🐥
 
  • #2,846
Klystron said:
Correction: Bitter sweet. 🤐 Dark chocolate bitter. Yet sweet, like birdsong. 🐥
Dark chocolate is healthier than the milky types, e.g. it is has a mild anti depression effect. Even when it comes to sweets like chocolate, what tastes better is worse. I would be first at the vegetable shelves if they only tasted like steaks :biggrin:
 
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Rx7man said:
The problem with that is in some places trees grow really fast, and places that weren't forest, become forest and can't be cut back.. I know this from the Ticin, where there are a lot of little cottages on acreages that got abandoned
Switzerland has a high population density, especially if we subtract the places so high that they don't support either population or forest. It's not like there would be large areas no one cares about.
 
  • #2,848
Appaget said:
Today I taught differentials and integrals
Good for you. What did you LEARN today?

Or do you mean you taught them to yourself?
 
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  • #2,849
phinds said:
Good for you. What did you LEARN today?
The best way to learn something is to teach it. But I learned that a long time ago. While teaching.
 
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  • #2,850
jbriggs444 said:
The best way to learn something is to teach it. But I learned that a long time ago. While teaching.
Yep. It is a mean trick. One has to convince oneself first!
I wished some politicians would try this.
 
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  • #2,851
jbriggs444 said:
The best way to learn something is to teach it. But I learned that a long time ago. While teaching.
If you can't explain it to someone else then you don't understand it. Feynman?
Edit, No it was Einstein and it was, 'If you can't explain it simply...'
 
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  • #2,852
fresh_42 said:
TIL that Switzerland has a real good law: What once is forest, has to stay forest!
BillTre said:
In Oregon, its more like:
what was once forest, if now it is made not forest,
replant it to make it forest again (for a while).
I've also seen the logic 'burn forests to expand cities!' ... Too bad, I tell you that.
 
  • #2,853
Today I learned more about salt water pools and water quality.

Our Fair City, famous in song and story for scams and corruption that would cause a Vampire to blush, has issued new health regulations on allowable levels of cyanuric acid (CYA) in swimming pools forcing pool owners to change the water ~once a week. In the desert.

CYA is added as a component of the "approved" chlorine tablets added to ensure water quality, delaying UV effects on free chlorine in swimming pools. The only information on the new regulations I can find so far is written by swimming pool maintenance companies who profit greatly from the new regulations. The City health regulations remain impenetrable.

I am trying to educate local home owners on the benefits of salt water pools with a simple ionizer to dissociate the sodium and chlorine from table salt disolved in the water. The chlorine and salt are almost unnoticeable while the sodium "softens" the water and feels silky smooth.
 
  • #2,854
That cyanuric acid limit seems to apply to public pools (including HOA maintained ones), not private pools. See:

http://www.southernnevadahealthdist.../Regualtions/20180705-Aquatic-Regulations.pdf
This site states that automated Chlorine feeder systems are available, for up to $9000.
https://www.reviewjournal.com/homes...district-implements-pool-regulations-1819109/
There is an informative two page fact sheet from the city of Sacramento, CA at:
http://www.emd.saccounty.net/EH/Documents/CYANURIC ACID FACT SHEET - 2015.pdf
Also note The World Health Organization has established an upper limit of 100ppm in swimming pools; at least according to pgs17-18, comment 5.7.3.2.1.2.1 of:
https://www.cdc.gov/healthywater/pd...nfection-and-water-quality-code-and-annex.pdf
Sounds like your Fair City is trying to put teeth into enforcement.

Edit: references found with:
https://www.google.com/search?&q=las+vegas+health+code,+swimming+pool,+cyanuric+acidCheers,
Tom
 
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  • #2,855
Thanks for the wider perspective, Tom.

Our Fair City, where all sins are forgiven even as they occur, where time stands still while you have money to spend, an open cesspool of sun drenched ... wait, I forgot what I was going to ask. :cool:

I am baffled why the HOA pool maintenance contractor uses so much CYA? I used to add chlorine and "pH down" to my private pool, testing for correct levels then a spritz of CYA to help preserve the chlorine. Then I switched to salt water and an ionizer that kept the chlorine levels spot on. Less costly than the $9k USD insertion system with many other benefits. I found some videos to show the HOA board about salt water pools.
 
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  • #2,856
Klystron said:
I am baffled why the HOA pool maintenance contractor uses so much CYA?
Because he can earn more profit that way? It's easier than testing for the acid?

I know only what I read in the references I supplied, but apparently the acid accumulates in the water and even clings to the pool walls upon emptying. Don't know if it stays active re the Chlorine but might be worth investigating.

BTW my references were found with:
https://www.google.com/search?&q=las+vegas+health+code,+swimming+pool,+cyanuric+acid
Cheers,
Tom

p.s. the 'CYA' abbreviation works in context but was initially interpreted as 'Cover Your A**'! o_O
 
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  • #2,857
mfb said:
It is based on trophy points, the increasing levels are in increasing mass and size (until it goes into the speculative region).
Yes, the increasing PF levels are in increasing both mass and size.
But there are some exceptions; e.g. Quarks are -at least 4 times- more massive than Electrons. In this case, only their size is notable. (Electrons are larger than Quarks; so 0≤Quark<10<Electron)
pinball1970 said:
I noticed that I am a pf molecule the other day and I thought it was very sweet
I've just found a relation between trophy levels: (numbers are trophy points)

0Quark<10<Electron<30<Atom<50<Molecule<100<Cell<150<Organism<200<Mountain
200<Mountain<300<Ocean<400<Asteroid<500<Moon<600<Planet<700<Star<800<Galaxy
800<Galaxy<900<SuperCluster<1000<Universe<1100<Multiverse<1200<Singularity<1300

(The only member that has reached singularity is fresh_42, so the next level is Unknown at present.)
By my relation, you can find out the correct order of these levels and calculate how many trophies you need to reach next achievements.
Hope that it will be helpful for members not so familiar with PF.:smile:
A M
 
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  • #2,858
Mountain and galaxy are there twice.

Both quarks and electrons are expected to be point-like, but the wave function of quarks is typically confined to a smaller space than electrons.
 
  • #2,859
mfb said:
Mountain and galaxy are there twice.
I think that would make it easier to analyze. (To avoid little confusion due to multiple lines.)
mfb said:
but the wave function of quarks is typically confined to a smaller space than electrons.
And that's why: 0≤Quark<10<Electron :smile:
 
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  • #2,860
Klystron said:
I am trying to educate local home owners on the benefits of salt water pools with a simple ionizer to dissociate the sodium and chlorine from table salt disolved in the water. The chlorine and salt are almost unnoticeable while the sodium "softens" the water and feels silky smooth.

Sounds relaxing, your worries dissolve, Then so do you?
 
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  • #2,861
Today I learned that nearly all the bananas in the world are practically a clone, that reproduces asexually, so cannot easily adapt nor do breeders have a great resources to combat a new menace of a fungal infection which after having devastated in Asia and Africa is turning up also in Columbia.

I didn't wish to know that.
 
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  • #2,862
epenguin said:
Today I learned that nearly all the bananas in the world are practically a clone, that reproduces asexually, so cannot easily adapt nor do breeders have a great resources to combat a new menace of a fungal infection which after having devastated in Asia and Africa is turning up also in Columbia.

I didn't wish to know that.
I read an article some time back that said all the bananas we eat today are an inferior species that was all that could be recovered and re-populated from a massive banana blight in the (I think it was) early part of the 1900's and that if another such blight occurs it will likely again totally wipe out the current banana species.

Where I've said "species" it's possible I should have said "hybrid". Not sure.
 
  • #2,864
epenguin said:
Today I learned that nearly all the bananas in the world are practically a clone, that reproduces asexually, so cannot easily adapt nor do breeders have a great resources to combat a new menace of a fungal infection which after having devastated in Asia and Africa is turning up also in Columbia.

I didn't wish to know that.
As a child in the 1960's I remember eating bananas or plantains from a private garden planted circa 1868 in Santa Barbara CA. Do not remember colors but they were shorter wider flatter than Dole store-bought, bittersweet with small soft seeds. The plants were tall enough to shade upper floors; like bamboo with yummy fruit.

They were gone a few years later when I lived at the college. "Attracted rats." said Brother Caretaker.

[Edit: Brother Simon, a man of few words, actually said "Ratten" in German. The other kids thought he said "rotten" as in spoiled fruit. We spent that afternoon clearing overgrown prickly pear cactus. I learned a new word glochid.]
 
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  • #2,865
Klystron said:
As a child in the 1960's I remember eating bananas or plantains from a private garden planted circa 1868 in Santa Barbara CA. Do not remember colors but they were shorter wider flatter than Dole store-bought, bitter and had small soft seeds. The plants were tall enough to shade upper floors; like bamboo with yummy fruit.

They were gone a few years later when I lived at the college. "Attracted rats." said Brother Caretaker.
I hope these wild types are all in botany labs around the world. We never know when we may need to reintroduce them.
 
  • #2,866
Today I learned that the bond formed by red oak and Titebond III is over twice as strong as that formed by any other domestic (US) wood and any other glue tested: a traditional yellow glue (PVA), a Type I waterproof PVA [Titebond III], a liquid hide glue, a hot hide glue, a slow-set epoxy, and a polyurethane. (Case Western Reserve 2007).
 
  • #2,867
Maybe not today... but a few days ago I learned:

A library that I frequent has an (online) institutional subscription to the journal _Nature_.

Not only does this solve a paywall problem, but I now have an all new time-sync.

diogenesNY
 
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  • #2,868
diogenesNY said:
Not only does this solve a paywall problem, but I now have an all new time-sync.

Did you mean a 'time-sink', or are you syncing your reference frames? :wink:
 
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  • #2,869
My dear Mr. Lexicop... while I was almost inclined to plead fully and totally guilty to the former... I think I will just claim the latter on the basis of: "well, if _Nature_ isn't a sufficiently authoritative source, well, then to the devil with all of it!" and why the hell not? :)

diogenesNY
 
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  • #2,870
TIL that pink Himalayan salt, when escaping from an open container that your girlfriend's daughter just tossed into the air while dancing in the kitchen, looks oddly similar to what happens when two galaxies interact with each other. A beautiful arc of pink color, like the arc of gas, dust, and stars following the interaction.
 
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