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Aluminum foil (2021)

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Re: Aluminum foil (2021)

#91

Post by manwe150 »

Perz1val wrote: post #64
jacobgold wrote: post #56

Earlier quoted context omitted.

You shouldn't use aluminum foil with tomato/lemon/vinegar/brined foods or as "grilling packets" (direct fire/high heat) because of leaching risk. There's no concern with using aluminum in most cases (with dry/non-acidic foods) but leaching is a real problem with acidic/salty/wet/high eat.

I put aluminium foil over a bowl of pizza dough, as it grew the top touched the foil and in a few spots tiny holes appeared in the foil. I wonder if it was carbonic acid or what

It probably formed a weak battery electrode with the bowl and electro-deposited it on the substrate (pizza). Happens often with tomato sauces, like lasagnas.

Re: Aluminum foil (2021)

#92

Post by AnIrishDuck »

HPsquared wrote: post #76
upofadown wrote: post #73

>...and conductive, rivaling copper. That isn't true for either thermal or electrical conductivity. So I don't know what is meant here.

Aluminium is usually "good enough" relative to copper on both types of conductivity, and it soundly beats copper in terms of conductivity per unit weight (which is the metric of interest in many applications) and presumably in terms of material cost too. Copper is better if you want minimum physical size, though. (EDIT: Copper does have some durability advantages though which is another reason it's often favoured)

It is indeed the conductor of choice at utility scale. It was even briefly used in place of copper wire in construction [1], though that usage was halted when safety issues emerged (differential expansion when mated with legacy copper pulled apart joints and created major fire hazards)

1. https://en.wikipedia.org/wiki/Aluminum_building_wiring

Re: Aluminum foil (2021)

#93

Post by Bender »

kragen wrote: post #75
jacobgold wrote: post #56

Earlier quoted context omitted.

You shouldn't use aluminum foil with tomato/lemon/vinegar/brined foods or as "grilling packets" (direct fire/high heat) because of leaching risk. There's no concern with using aluminum in most cases (with dry/non-acidic foods) but leaching is a real problem with acidic/salty/wet/high eat.

Let's see if this is a quantitatively plausible concern. https://en.wikipedia.org/wiki/Aluminium_chloride says orl-rat LD₅₀ of AlCl₃ is 380mg/kg, which is 20.2% aluminum by weight, so that's 77mg/kg of soluble aluminum ions. If this toxicity is due to soluble aluminum ions (rather than, say, acidity), and rats and humans are about equally sensitive to aluminum toxicity, you'd need about 3.8g of aluminum to kill a 50k…

How long does it take to leave the body?

Re: Aluminum foil (2021)

#94

Post by js2 »

penguin_booze wrote: post #90

The name of the metal is Aluminium. Of course, America had to introduce yet another typo.

Maybe you're just taking the piss from over the pond, but the differing names/spellings aren't just a typo by us dumb, arrogant Americans:

https://en.wikipedia.org/wiki/Aluminium#Naming_and_spelling_...

Cheers. :-)

Re: Aluminum foil (2021)

#95

Post by cineticdaffodil »

aradaelli wrote: post #33
whilenot-dev wrote: post #19

Earlier quoted context omitted.

I made an artwork in 2013-ish, where I attached an aluminum foil to a good DC motor. I mounted it from the ceiling with 2 stepper motors to control height and one orthogonal axis. The motor would unwind the foil by accelerating quickly in either direction (CW/CCW). By changing directions it would also create folds and stabilize the emerging shape: https://imgur.com/a/gaRKGtQ I always imagined an additional stepper mo…

Imgur is not working anymore in UK :(

United Korea is best korea!

Re: Aluminum foil (2021)

#97

Post by kragen »

manwe150 wrote: post #91
Perz1val wrote: post #64

Earlier quoted context omitted.

I put aluminium foil over a bowl of pizza dough, as it grew the top touched the foil and in a few spots tiny holes appeared in the foil. I wonder if it was carbonic acid or what

It probably formed a weak battery electrode with the bowl and electro-deposited it on the substrate (pizza). Happens often with tomato sauces, like lasagnas.

Oh, thanks! You are surely correct; I was puzzled about how something as relatively inert as pizza dough could corrode aluminum at multiple microns per hour, but electrolysis can definitely do that.

Re: Aluminum foil (2021)

#98

Post by manwe150 »

badc0ffee wrote: post #29

It's non-toxic and food safe, and yet a significant number of people on the internet still act like it's poison that will give you Alzheimer's. I wonder how many of those people touch their lips to the lid of an aluminum beverage can. Or how they might bake a lasagna at home.

That aluminum beverage can (and also tin cans) is lined with a kind of plastic, so you and food aren’t in contact with the actual aluminum in that case

Re: Aluminum foil (2021)

#99

Post by badc0ffee »

manwe150 wrote: post #98
badc0ffee wrote: post #29

It's non-toxic and food safe, and yet a significant number of people on the internet still act like it's poison that will give you Alzheimer's. I wonder how many of those people touch their lips to the lid of an aluminum beverage can. Or how they might bake a lasagna at home.

That aluminum beverage can (and also tin cans) is lined with a kind of plastic, so you and food aren’t in contact with the actual aluminum in that case

But the top of the lid is unlined, I think.

Re: Aluminum foil (2021)

#100

Post by hatthew »

jstanley wrote: post #83
cdu1 wrote: post #30

Earlier quoted context omitted.

I think the implication is you can use it to reflect additional light onto your photocell, improving the power output for a smaller cost than purchasing an additional cell.

Why aren't photo cells already manufactured to be like 90% mirrors then?

Some guesses:

- A lot more direction-dependent.

- More maintenance related to keeping the right direction, maintaining more moving parts, etc.

- Less convenient form factor, more susceptible to wind, more unsightly.

- Less space-efficient, which matters for some applications like house rooftop installations.

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