People like you finding it interesting is literally the definition of what should be posted on HN.
That said, I would love it if the OP game some additional context on why they submitted it - is this a response to something? Was there a new advance here? Just something cool they saw?
I wish here was a good way to include context with a bare link. In this case, I just learned the rat in The Abyss was actually submerged in breathing fluid, a substance I thought was fictitious. This blew my mind, so I shared.
Although I am wearing a scifi hat, not reality, assuming they don't need to breathe in hibernation, the full fluid immersion is probably a good way to regulate internal body temperature.
I seem to remember this being in the book "The Sphere", though I might be wrong. I actually always thought that it was something rarely-used-but-possible.
The overlap between close-to-current sci-fi and real life in my brain is occasionally saddening/shameful.
This is why I posted the link. I never realized the liquid was real and that the scene was shot using it. After watching the scene I thought, did they drown that rat? Effects were good, but not that good!
The critical bit for many interesting practical applications is this:
A significant problem, however, arises from the high
viscosity of the liquid and the corresponding reduction
in its ability to remove CO2.[3][20] All uses of liquid
breathing for diving must involve total liquid
ventilation (see above). Total liquid ventilation,
however, has difficulty moving enough liquid to carry
away CO2, because no matter how great the total pressure
is, the amount of partial CO2 gas pressure available to
dissolve CO2 into the breathing liquid can never be much
more than the pressure at which CO2 exists in the blood
(about 40 mm of mercury (Torr)).[20]
This has been a known issue since the 50's and shows no sign of going away. The paragraph is a bit muddled--it's the diffusion coefficient, not the viscosity, that is relevant--but the inability of oxygenated liquids to carry away CO2 has so far been the major impediment to doing any of the really cool things this technology has promised for so long.
The critical bit for many interesting practical applications is this:
A significant problem, however, arises from the high viscosity of the liquid and the corresponding reduction in its ability to remove CO2.[3][20] All uses of liquid breathing for diving must involve total liquid ventilation (see above). Total liquid ventilation, however, has difficulty moving enough liquid to carry away CO2, because no matter how great the total pressure is, the amount of partial CO2 gas pressure available to dissolve CO2 into the breathing liquid can never be much more than the pressure at which CO2 exists in the blood (about 40 mm of mercury (Torr)).[20]
At these pressures, most fluorocarbon liquids require about 70 mL/kg minute-ventilation volumes of liquid (about 5 L/min for a 70 kg adult) to remove enough CO2 for normal resting metabolism.[21] This is a great deal of fluid to move, particularly as liquids are generally more viscous than gases, (for example water is about 850 times the viscosity of air[22]). Any increase in the diver's metabolic activity also increases CO2 production and the breathing rate, which is already at the limits of realistic flow rates in liquid breathing.[3][23][24] It seems unlikely that a person would move 10 liters/min of fluorocarbon liquid without assistance from a mechanical ventilator, so "free breathing" may be unlikely.
In babies, I would guess that some of the amniotic fluid is also absorbed into the blood stream. Both that and evaporation seem much less likely to work with perfluorocarbons.
Forgive me for being a bit too simple on this subject - wouldn't having a liquid in your lungs, throat and mouth really make it difficult or impossible to talk?
Not sure using it for diving or space travel is a great plan if that's the case. Sure you could have a text or flashing lights method of talking but there's no communication method faster than yelling "HELP!" into your radio that I can think of
See, there is an air intake in your mouth - and trying to talk under water does not exactly result in the noises you expect when you're talking into air.
The sign used by divers to alert others is banging your knife against the air tank. There are actual hand signs for 'I'm in trouble' or 'I'm out of air'.
Fair enough, like I say I'm not familiar with the subject but curious. I was more picturing the masks that look a bit like gas masks that have radios in them. My extent of diving knowledge is limited to movies and Mythbusters, I'll admit.
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[ 4.1 ms ] story [ 72.0 ms ] threadThat said, I would love it if the OP game some additional context on why they submitted it - is this a response to something? Was there a new advance here? Just something cool they saw?
The overlap between close-to-current sci-fi and real life in my brain is occasionally saddening/shameful.
Not sure using it for diving or space travel is a great plan if that's the case. Sure you could have a text or flashing lights method of talking but there's no communication method faster than yelling "HELP!" into your radio that I can think of
See, there is an air intake in your mouth - and trying to talk under water does not exactly result in the noises you expect when you're talking into air.
The sign used by divers to alert others is banging your knife against the air tank. There are actual hand signs for 'I'm in trouble' or 'I'm out of air'.
Thanks for that information :)