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De-Icing with Electricity, Not Heat
danspalding writes: "The New York Times has this article about using eletricity against ice. Turns out ice creates a reverse charge in whatever it binds to, and that that charge can be neutralized. Battery-powered ice cream scoopers can't be far behind."
H+ = a proton
Only the H+ ion has to move, not an entire atom.
Games Workshop Petition
Another difficult problem with ice is not only with tires and airplane wings -- it is with the roads one walks on. Having skidded my way to classes more than once (walking on paved pathways) I would be very interested if they could develop this technology as a "film." The relative cost savings for both car windshields, and snow plows would be insane. You probably could also charge people fees to watch "popcorn snow." Imagine the snow/ice bouncing off your driveway, visibly. This would definetly be something I would like to see.
University of Illinois has a very good article (with pictures!) about Proton conduction, proton channels, proton wells on water.
This page about Victor Petrenko, a little more technical than Slashdot's article
This one is brief, but says: "PROTONIC CHIPS NEVER FORGET Researchers at the University of New Mexico and Sandia National Laboratories are investigating the use of protonic memory for making cheap forget-me-not computer chips. In 1995, they noticed during experiments on silicon wafers that protons deep within the wafers were responding to electrical signals on the surface. "Nobody had seen these moving protons before," says one scientist. Further research showed the protons can be precisely controlled with standard microcircuits -- and are thus able to store data. Protonic chips won't need the fancy processing used in "flash" and other so-called nonvolatile memory chips, and can operate at very low power levels, thus prolonging battery life in laptops. Protonic chips currently are being tested at Texas Instruments.
This PDFexplains the Mechanism of proton diffusion in the solid state protonic conductor Rb3H(SeO4)2, wich I assume is somewhat equivalent to the ice (haven't read the whole article yet) This
Using the electric heater, you end up getting water running down the windscreen, and it takes an age - plus as soon as you stop heating the windscreen, all that water that still exists as a film on the screen will re-freeze. Using this method, the ice just jumps off the screen almost instantaneously, without melting, and leaving your windscreen (relatively) dry, and so it will not refreeze.
"Also, when the H2 and O2 ignite, wont the explosion send shards of ice flying?"
Since the layer of gas is very thin, it should only be enough to "pop" the ice off the glass due to the expansion of the ignited gas. I don't think there would be any explosion - the shedding effect would be due to the gas expanding, not igniting. Watching it happen would be like the ice just falling off the screen, as the bonds between the two surfaces are broken.
Games Workshop Petition
There's a detailed description and diagrams here. The process is referred to as the Grotthuss "hop-turn" mechanism.
Kind of like the old-style ski turns, though I think those are called stem-christies. (OK, it makes more sense if you've read the article and looked at their little sidebar image...)
The amount of gas produced would be very small.
Let's say there is 1 gram of ice on the windshield of your car. Given water is 18 grams/mole, that would be 0.056 moles of water on it.
Now, since for every 1 mole of water, you will get 1 mole of hydrogen and half a mole of oxygen, you will get 0.056 mole of hydrogen and 0.028 mole of oxygen.
Given gas occupies about 22.4 L at 1 atm, 0 degrees Celcius, about 124 mL of hydrogen and 62 mL of oxygen will be produced out of 1 g of water.
While that may seem a lot to be produced, all of that will be formed on relatively large area, about 1 or so square meters. Therefore, they will be dissipated into the air very very quickly (less than a second).