The magic of water or we still do not even understand water!
Just two days ago, I blogged here about "Direct evidence emerges for the existence of two forms of liquid water"
Quick reminder: We don't yet even understand water fully, but Western societies are inundated on a daily basis with the pseudoscience and pretense of knowledge of Global Warming and Climate Change!
"‘Quantum friction’ – a component of friction not present in classical physics, has been postulated by researchers in France to explain anomalies in the behaviour of water at carbon-based surfaces like graphite, graphene and carbon nanotubes. The phenomenon’s generality is not yet known, but it could potentially be useful in fields such as desalination that require selectively permeable membranes. ...
However, this fails to explain some odd experimental observations: notably, water flows through microfluidic channels in graphene much faster than in bulk graphite. More bizarrely, ... found that, when multi-walled carbon nanotubes become narrower, water actually flows through them faster. ...
describe these collective charge fluctuations in flowing water as quantised excitations called ‘hydrons’. These hydrons cannot dissipate significant amounts of energy into graphene, the researchers calculate, so only classical friction is important. When water flows past bulk graphite, however, hydrons resonantly excite quantised electron density fluctuations called plasmons, thereby slowing down the water. ‘Graphite has this very peculiar surface plasmon that has precisely the right energy and momentum to talk to the hydrons,’ ... ‘Water friction is not anomalously low on graphene, but instead it is anomalously high on graphite,’ the researchers write. In this case, the quantum friction can be about 10 times as large as the classical friction. ..."
However, this fails to explain some odd experimental observations: notably, water flows through microfluidic channels in graphene much faster than in bulk graphite. More bizarrely, ... found that, when multi-walled carbon nanotubes become narrower, water actually flows through them faster. ...
describe these collective charge fluctuations in flowing water as quantised excitations called ‘hydrons’. These hydrons cannot dissipate significant amounts of energy into graphene, the researchers calculate, so only classical friction is important. When water flows past bulk graphite, however, hydrons resonantly excite quantised electron density fluctuations called plasmons, thereby slowing down the water. ‘Graphite has this very peculiar surface plasmon that has precisely the right energy and momentum to talk to the hydrons,’ ... ‘Water friction is not anomalously low on graphene, but instead it is anomalously high on graphite,’ the researchers write. In this case, the quantum friction can be about 10 times as large as the classical friction. ..."
From the abstract:
"... Here we develop a quantum theory of the solid–liquid interface, which reveals a new contribution to friction, due to the coupling of charge fluctuations in the liquid to electronic excitations in the solid. We expect that this quantum friction, which is absent in Born–Oppenheimer molecular dynamics, is the dominant friction mechanism for water on carbon-based materials. As a key result, we demonstrate a marked difference in quantum friction between the water–graphene and water–graphite interface, due to the coupling of water Debye collective modes with a thermally excited plasmon specific to graphite. ..."
Fluctuation-induced quantum friction in nanoscale water flows (no public access)
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