
Nanorods: water-oozing material could help quench thirst - wallflower
http://www.pnnl.gov/news/release.aspx?id=4282
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ChuckMcM
That is a really fascinating result. It would also explain the mechanism of
graphene sieves. One of the really amazing behaviors of graphene is that you
can pour water on top of it, and pure water pops out of the bottom[1].

[1] [http://phys.org/news/2016-03-revolutionary-graphene-
filter-c...](http://phys.org/news/2016-03-revolutionary-graphene-filter-
crisis.html)

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coolsunglasses
So it deionizes the water too? Wow. If this technology does the same, doesn't
that imply we'd need to supply people using this as a source of water with
electrolytes and minerals for the water?

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MollyR
I often wonder if this matters anymore, since food has a high amount of salt,
and minerals.

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coolsunglasses
The food in developing countries doesn't necessarily.

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Aelinsaar
This is pretty exciting, and the applications are almost unlimited, and many
of them highly marketable. Athletics clothing alone is billions of dollars
around the world, but this a key too:

 _" "But before we can put these nanorods to good use, we need to be able to
control and perfect their size and shape," added Nune, the paper's other
corresponding author."_

It seems to me that could be a long process, along with the challenges of
scaling up manufacturing. Still, at some point, this is going to be a very
useful material.

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CamperBob2
_These papers also noted the process was theorized as early as the 1990s by
scientists examining crystallized proteins. Back then, scientists noticed they
only saw water vapor surrounding hydrophobic sections of protein, while liquid
water would surround other areas. The researchers proposed that there was some
sort of process that enabled the water caught between hydrophobic protein
sections to suddenly vaporize._

This seems reasonably obvious, at least in retrospect. Trap a very small
number of water molecules in a region where they can't combine with others to
form a liquid, and it's reasonable to expect those molecules to simply waft
away. A molecule made from two hydrogen atoms and an oxygen atom weighs much
less than the diatomic oxygen molecules in the air, so why wouldn't they
displace those molecules?

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tener
Could someone with appropriate background explain where does the energy to
evaporate the water come from?

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nsxwolf
Can they work the other way - could you build a solid state dehumidifier with
these?

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derefr
Activated charcoal is already a pretty good dehumidifier; this just seems to
take the adsorptive properties of high-surface-area carbon one step further by
giving the water an easy path "out" once it's adhered and amassed, keeping the
carbon from getting "used up."

I wonder if a similar thing could be done with silicon nanorods, given the
similarity between activated charcoal and silica gel. "Silicon nano rods"
sounds a lot like asbestos—and apparently asbestos _is_ adsorptive, just not
of water—but asbestos is micro-scale at best. Meanwhile, SiO2 nano _tubes_
apparently exist[1], but don't show any particular adsorptive properties.

[1]
[https://en.wikipedia.org/wiki/Silicon_nanotube](https://en.wikipedia.org/wiki/Silicon_nanotube)

