Melting Away Ice Hazards

RadioheadKid writes "Dartmouth College Professor Victor F. Petrenko is getting a grip on ice. He and his colleagues have found ways to take advantage of the "protonic" semiconductor properties of frozen water. They see many applications of this discovery from melting ice on power lines to electronic speed control for skis and snowboards. I guess those Petrenkos just love the ice."

Fascinating stuff

[The Tyro]

Protons carrying the charge, hmmm? I suppose any charged particle could theoretically carry a current, but I must admit I never thought of "proton flow" as a way to do it...

Water really is an interesting material.

Universal solvent (polar solvent, for you organic chemistry nitpickers)

Has its greatest density BEFORE it reaches its solid state of matter (ice). If you ever wondered why ponds and rivers don't freeze from the bottom up, that's the reason. Someone correct me, but I think the temperature of greatest density is 39F.

That's really quite a discovery... can't wait to see if they can make something useful out of it.

The article mentions...

[Jace of Fuse!]

The article mentions the possibility of making car tires that get 90% better grip in icy conditions, yet this article cares more about skiers.

For some reason, I'm thinking someone's vision on the uses for technology is a little out of focus here.

Re:The article mentions...

[uptownguy]

The article mentions the possibility of making car tires that get 90% better grip in icy conditions, yet this article cares more about skiers.

For some reason, I'm thinking someone's vision on the uses for technology is a little out of focus here.

...Or maybe they don't live in shockingly cold places like many of the rest of us (Minneapolis, MN here -- hi everyone) where they need to DRIVE in conditions like that constantly for 5-7 months of the year. It is one thing to live in Southern California and take a drive to the mountains to ski every once in a while -- it is something else completely to have to drive 20 miles to work on a frozen freeway...

How skis work

[squidgyhead]

The article talks about how their discovery can be applied to skiing, and, analogously, driving and a bunch of other stuff, by melting ice and making it more or less slippery, depending on the interval between meltings. Small interval => more water, less freezing, large interval => more freezing, less slippery water. You get the idea.

I imagine that most of you know the ideal gas law, ie that pressure and temperature are (almost) linearly related. So, if you increase the pressure, you should be able to melt snow or ice, right? If it gets colder, you just squeeze harder. This means that warm snow should be slipperier, since you can melt more snow, which will lubricate better, right?

Unfortunately, below 30 degrees Celsius or so, there is no way to get water, no matter what pressure you apply. Look at the following ice/water/vapour [sbu.ac.uk]
diagram. You will notice that vapour and liquids don't take up much of it, it's ice almost everywhere. And all ice below 240K (=-33C) or so.

So how could we possibly ski at below -33C? The answer is that we just slide on the snow. Occam's razor, ya?

Re:Great...

[mattcasters]

Actually, the record is 248.105km/h or 154mph. A man named Harry Egger did it.

WorldRecord 1999 [speedski.com]

I've seen them ski in Les Arcs (France) in 1999 and although the view was very impressive, since then I'm convinced that these people are completely nuts or incredibly brave. :-)

Furthermore, I think that reducing ski-resistance is not going to help these people. I think it's wind resistance that's holding them back.

Cheers, Matt

piezoelectric roads?

[sporkboy]

The low power requirements of a system like this remind me of an idea that I had a while back. High-ice surfaces such as bridges (freeze first) could be equipped with a system like this to melt the ice, and the power for the system could be generated by the pressure generated by the weight of passing vehicles. Some sort of storage mechanism would be needed, at least small scale, to keep the ice off when traffic isn't passing.

Of course IANAEE (I am not an electrical engineer) so I could be speaking from the wrong end here. Not sure on costs of such a system either but it seems like it could have benefit, especially considering how expensive bridges are to begin with.

solar power

[roman_mir]

"Many properties are completely different, but there are similarities between ice and the usual semiconductors," he says. For instance, he discovered that ice crystals can exhibit protonic photoconductivity. "It would be possible to create an ice solar cell," albeit one with substantially lower efficiency than silicon. Field effect transistors made of ice have also been developed that "work the same way as silicon."

Ok, who right away thought of turning north and south poles into electricity generating power plants?

Wireless skis

[isdnip]

I like his adjustable skis. But how do you set the speed? It's not practical to bend over and tweak a knob on top while going down a hill; at least, it would not be good style.

But if the control circuit used, say, Bluetooth, and the control buttons were in, say, the pole handles, then the skier would have good control while staying in motion. This could be quite nice.

(If somebody tries to patent the idea with a later date than today, remember, you heard it first on Slashdot, making it potentially Prior Art.)