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Janus Particles as Body Submarines?
Roland Piquepaille writes "Janus particles, which take their name from a Roman god with two faces, are microscopic 'two-faced' spheres whose halves are physically or chemically different. Now, U.S. researchers have shown that some of these Janus microparticles can move like stealthy submarines when an alternating electrical field is applied to liquid surrounding them. This could lead to new kinds of self-propelling microsensors or means of targeted drug delivery."
From the article:
The application of ac electric fields in aqueous suspensions of anisotropic particles leads to unbalanced liquid flows and nonlinear, induced-charge electrophoretic motion.
Well, duh. Everyone *already* knew that!
Two faced particles that stealthy move in a liquid. Pick up any government, and you can make the same observation. I wonder if the findings of the research team are applicable to macroscopic solutions?
But will pilots have to use revealing clothing? After all, that's what turns a mediocre journey into an amaaaazzzing journey.
Ginga no Rekshiya Mata Each page.
I can see these particles having uses outside of the medical world, such as a motor with no moving parts that can be scaled down. I cannot however see these having use in medicine, since humans are great big electrical conductors who are also very sensitive to electricity being pumped through them.
Soap molecules are not spherical, really. They are more of like a match, with a lipophobic head and a lipophile body. Now, when they help dissolve fat in water, a number of molecules tend to form spheres, leaving the fat inside, This phenomenon has been exploited for ages to, ehm, wash dishes and the like. Also, a more sophisticated version of this idea has also been around for quite some time: liposomes.
The idea behind TFA is using spheres with two halves. Sort of a dipole that may move around under the effect of an electric field (if I got it right).What galls me is how they "water-down" even the simplest of details, such as what range of frequencies were used to drive the particles. And I fail to understand what that frequency has anything to do with the 50/60 Hz that comes from your wall socket. Maybe I am missing something here. It would be far more informative to see the range -- in exact numbers -- of frequencies used and where they saw the peak performance, where the performance drops off, etc.
But then, that's my general pet peeve whenever a non-scientist attempts to report on a matter of science. Details are dropped out or distored all over the place. Just to get at even the minimal details I'll have to go to the actual scientifc publications, which, BTW, Eurekalert fails to provide any references or links to.
So, a bit of lousy reporting if you ask me, on something otherwise truly interesting.
Ruby Neural Evolution of Augmenting Topologies
"Body Submarines"? That doesn't mean some drug, it means a nanothin film I can wear on my body that lets me dive to thousands of meters under the sea!
AC current flows across the surface of human skin without chemically or physically affecting the human, if cycled at the proper frequencies. Let's see them gin up some hydrophilic/phobic janus particles that can lock together with titanium strength, but contour their shape to the body surface as defined by the AC flows across the skin. Modulating the AC flow pattern to expand out and contract again as we breathe from an air tank. We wouldn't even need special diving NOx mixes, because we wouldn't be pressured anymore into the bends.
And since the diameter of the "hull" would be only something like a half meter or so, instead of the several meters of submarine ships, we might keep structural integrity to really vast depths at which the relatively cavernous submarine ships would be crushed without internal support, given their surface:volume ratio. It all depends on the physics of the janus particle made for this app.
And given a thin dynamic surface modulated with AC across the dynamics of our flexible skin, we could even preserve our sense of touch, and even let our noncompressible hairs stick out, so we can feel the water and whatever we touch in it. Though we could selectively armor areas into gloves or other protected areas, again by modulating the AC.
On land, these sheaths could be invisible body shields, that weigh practically nothing, but redistribute force of incoming blows.
Science is cool. Science fiction, given the good science, is fun!
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make install -not war