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The most official water costs $120k a gallon

signoregalilei.com

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Re: The most official water costs $120k a gallon

#151

Post by cozzyd »

ameliaquining wrote: post #104
thayne wrote: post #39

Earlier quoted context omitted.

At the very least that has the advantage that it's possible to make more of it, so you aren't dependent on a limited sample of standard water.

The article doesn't mention this, but they actually did make more. Or rather, they put together a new sample, VSMOW2, in 1999. It's exactly the same as VSMOW, to within measurement error. Like the original, you can buy it from the USGS. Documentation (including how it was prepared): https://nucleus.iaea.org/sites/AnalyticalReferenceMaterials/... This actually goes both ways; VSMOW itself was carefully made (by mixing…

Just wait for the new reflecting pool standard of official water.

Re: The most official water costs $120k a gallon

#152

Post by cozzyd »

sgerenser wrote: post #148
eimrine wrote: post #144

Earlier quoted context omitted.

why do you consider the cubic inches will be useful to the rest of the world (world who does not use galons)?

Yeah, they should have stopped at hogsheads, which is a well understood quantity worldwide.

Without cubic furlongs I don't have a good intuition for the amount

Re: The most official water costs $120k a gallon

#153

Post by NooneAtAll3 »

artisinal wrote: post #5

This is why we should ditch Celsius for Kelvin. I never liked how we coupled 0 and 100 to where water freezes and boils under certain conditions. Kelvin doesn't rely on non-invariant reference points.

kelvin still has reference points - absolute zero and tripple point of water

good luck choosing which water, tho

Re: The most official water costs $120k a gallon

#154

Post by NooneAtAll3 »

chermi wrote: post #13
xgulfie wrote: post #12

Earlier quoted context omitted.

Kelvin does still rely on each degree being 1% of the way between freezing and boiling so it kinda does rely on a variant reference point

The reference point is the triple point, and invariant.

tripple point of what tho?

which water?

Re: The most official water costs $120k a gallon

#155

Post by fredoralive »

a3w wrote: post #77
spullara wrote: post #8

A US gallon of deuterium water costs roughly $2,600 to $3,800, while a gallon of pure tritium water (super-heavy water) would cost about $44 million.

How much volume is that for the rest of the world? Really unscientific article.

1 gallon is 0.832674 gallons. Or 1 gallon is 1.20095 gallons.

Re: The most official water costs $120k a gallon

#156

Post by kergonath »

cyral wrote: post #50
kccqzy wrote: post #45

Earlier quoted context omitted.

That’s a biased view that leads to a scale only convenient for people living in particular latitudes. Now talk to someone living near the equator like Singapore, and 0F is unimaginably cold (even 40F is basically unheard of), and 100F is very hot but not extraordinarily so. Then you talk to someone living close to the arctic and the converse is true. All this talk about 0F to 100F being frequently encountered probabl…

Now I'm imagining some kind of timezone-like temperature unit that varies around the world, and a "100 things programmers should know about ___" post about all the intricacies and special cases.

I cannot wait for leap degrees.

Re: The most official water costs $120k a gallon

#157

Post by kergonath »

al_borland wrote: post #27
warmdarksea wrote: post #18

Earlier quoted context omitted.

this is actually why i like fahrenheit the most... 0F is "really cold" and 100F is "really hot", whereas in celsius 0C is "kind of cold" and 100C is "uninhabitable". it makes sense for the 0-100 range to be reserved for temperatures frequently encountered in our habitat as humans i think...

This has always been my primary argument in favor of Fahrenheit. It makes sense for humans, which is all a majority of the population really cares about. In addition, it's more granular. Sometimes turning the thermostat up or down by 1C could be too much, where 1F is just right. In science and math, I can see where having round numbers for commonly used temperatures would be useful, but if 0C and 100C are the only pl…

> It makes sense for humans, which is all a majority of the population really cares about.

The Celsius scale makes perfect sense to me and the vast majority of humans in the world. Much more so than the Fahrenheit scale, which I absolutely never use. That’s not really a strong argument.

Re: The most official water costs $120k a gallon

#158

Post by kergonath »

tdeck wrote: post #107
Timpanzee wrote: post #56

Earlier quoted context omitted.

You only think it makes sense for humans because it makes sense for you, where you live the same way you feel changing a thermostat by 1F is perfect but 1C is too much: that’s true for you, not universally. Fahrenheit functionally requires you to be biased in order for it to seem like a good system.

> you feel changing a thermostat by 1F is perfect but 1C is too much: that’s true for you, not universally. I've noticed that here in Japan all the AC units seem to be adjusted by half a degree Celsius at a time, so I do think 1C is a bit much even for people who never used fahrenheit.

The good thing is that there is nothing preventing anyone from adjusting their thermostat with a decikelvin precision. Or hell, even centikelvin if they’re pushing it.

Re: The most official water costs $120k a gallon

#159

Post by bell-cot »

rwmj wrote: post #17

Interesting article but left me wondering why they don't use ¹H₂¹⁶O as the "standard water"? Surely you can make that (relatively) easily in a centrifuge by spinning out the lightest fraction of water.

Not an expert, but...

The use case for this water is calibrating ultra-precision instruments. The use case for those instruments is measuring water with normal-ish isotope ratios.

Calibrating your ultra-precision instruments to a point far away from their normal use case is asking for trouble.

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