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Science

Non-Wet Water 30

Posted by michael from the believe-it-or-not dept.
Symul writes: "ABCNews has posted a story today about water that, when mixed with a powder derived from the spores of cub moss, behaves much as liquids do in a weightless environment, with the properties of a sponge-like solid. The powder "coats" the droplets of water, adhering to its surface and little else, including itself. Suggested applications have been leak-free water transportation, and small scale lubrication."
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Non-Wet Water More

Non-Wet Water

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  • This effect has been used in magic tricks for a long time.


    OpenSourcerers [opensourcerers.com]
  • Yep...saw it there too!

    I remember back in high school chemistry calculating how many molecules of licapodium existed on the surface of the water b/c they spread out to approx. one molecule thick if you do it just right. That was just some very cool stuff...we estimated fairly close to what the "real" figure was...still neat playing with the stuff!
    ---
  • aaaaaaaaaahhhhhhhhhh... ok. :)

    Most nifty!
    ---

  • Fermat (Score:1)

    by bmo ( 77928 )
    I was using a cop-out like Fermat did when he wrote that line.

    I knew I was right, but I didn't feel like working it out; neither did he.

    Apropos, no? I propose a new html tag for "I Know I'm Right But It's Too Much Work To Prove", called the Fermat tag.

    Do you think that he actually had a proof or do you think he was bluffing? Note, I'm not putting the guy down; I wish that I could, when I die, leave people scratching their heads as much as he did.

    To expound for the people who are curious:

    Fermat's Last Theorem states that x^n + y^n = z^n has no non-zero integer solutions for x, y and z when n > 2.

    Well of course! You say. It's common sense!

    Try proving it.

    It took until 1993 (from when Fermat wrote his claim in 1630) for a brit named Andrew Wiles to nail it down.

    http://www-groups.dcs.st-andrews.ac.uk/~history/Hi stTopics/Fermat's_last_theorem.html

    Wiles' proof is still under scrutiny, as the last bit of the article says:

    "No proof of the complexity of this can easily be guaranteed to be correct, so a very small doubt will remain for some time. However when Taylor lectured at the British Mathematical Colloquium in Edinburgh in April 1995 he gave the impression that no real doubts remained over Fermat's Last Theorem."

    It's an interesting story, to say the least.

  • YOU should lay off the crack pipe...

    He's right. If you decrease the volume, the RATIO of surface area to volume goes UP.

    <Fermat>
    I have a proof for this, but it's too large to write in this margin.
    </Fermat>

    :-P

    This has real world implications, especially for biology. A shrew has problems keeping its body temp up because it radiates too much heat for its body size (see ratio above) so it has to eat, practically continuously, to be able to expend the energy to merely *heat its body*.

    Compare this to larger mammals which have less of a problem with temperature regulation.

  • Been there, done that.
    See also: ice plus and ice minus. FDA-banned, too. Fun!
  • Back in the day, maybe a decade or more ago. He had someone coat the surface of a water tank in the stuff, put their hand in and grab a nut from the bottom of the tank, they pulled their hand out and it wasn't wet. I forget what he called it though, Licapodium maybe.
  • No mod points, so I'll have to say this with a comment.

    Nice one! ;)
  • Tell me about it but it ain't the scientists. It's the damn reporter: 2 m/s is around 45 miles per hour and 1 cm is about a 0,4 inch. God, it's a wonder some people manage to be so dumb!
    Um, maybe you should check your math? 2 m/s is about 4.5 mph. 2 m/s == about 6.5 ft/s. For reference, 60 mph is 88 ft/s.

    They did screw up the cm->in conversion, though.

    Milalwi
  • This is why that NASA Mars probe ended up up in a million little bits...
  • We've had this for years. Just melt dry ice.
    ~
  • I'd thought of this too, but I thought one comment was enough for the day...
  • What the article doesn't mention is what the actual size of this water bead is. Everyone knows that the smaller the diametre of the bead, the larger the surface area for any given volume. So if they're big beads, then less powder is needed to form a bead, and presumably, less work is required to recollect the water, say, at the end of the pipe. But if the bead is very small, the there might be a reason for getting into the business of farming club moss!
  • that is a truly tweaked idea - but actually could be effective!!!
  • How's that?

    Surface Area = 4*pi*r^2 for a sphere, Since the diameter = 2*r and A ~ r^2, a smaller diameter means a smaller surface area.
  • No need for the Fermat bit...
    Surface area varies with the square of the radius, volume varies with the cube of the radius. So, as you increase radius, the ratio of surface area to volume decreases, and vice versa.
  • Boy guys check again. Its meters per sec not hours. 2m/s *3600s=7200m/h 7200m/h / 1000=7.2Km/h 1.0 Km = roughly 0.6 Mph so 7.2 Km/h * 0.6= 4.32 mph roughly.
  • I'm sure you did, I'm sure you did.

    In fact, why did you think I registered?

    Anyway, thanks for your reply. It makes me feel, wanted...
  • Heh, The only things I remember about Mr. Wizzard was that thing, and someone eating an apple standing on thier head.. :P
  • Of course they got it wrong, it's ABC News for heaven's sake...
  • Pesticide? I think HERBICIDE would be more appropriate... come to think of it, yeast infections tend to provide interesting secretions... maybe I should do a little mixing in the lab with water and "Candida albicans"....
  • Uhh, before you start getting all excited, what about the "little" problem of getting that darned moss out of your water on the other end of the pipe? If the stuff sticks so well to water, how are you going to do it? Filter? You'd have to change it all the time since it would get clogged fairly quickly, no? Distillation? I can imagine the cost; maybe plugging leaks wasn't such a bad idea... Yeah yeah I'm a party-pooper :)
  • Gives a whole new perspective on Steven Wright's comment, "I bought some powdered water, but I don't know what to add to it."
  • Tell me about it but it ain't the scientists. It's the damn reporter: 2 m/s is around 45 miles per hour and 1 cm is about a 0,4 inch. God, it's a wonder some people manage to be so dumb!



    --
    All browsers' default homepage should read: Don't Panic...
  • In tests now, the beads can reach rolling speeds of 2 meters per second (or about 4.5 miles per hour) without breaking and a coated water droplet can fall 1 centimeter (about one-fifth inch) without leaking. The water beads also resist merging -- in tests no two water beads have joined when in contact with each other.

    Since when did 1cm = 0.2in ?

  • LOL!!! :-)

    Nice to see that there are people just as sick as me!

    So do these spores reproduce? If you used it in conjunction with a condom, would she end up with a moss infection? What kind of pesticide would you need to combat it? I can see the commercial now:

    "Some days I don't feel as fresh, you know?"
    "When I have those days, I rely on Personal Agent Orange."
    "Thanks, Mom!"

  • There was a scheme about 20 years ago for mixing water with long-chain polymers, resulting in a liquid you could pour, but had to cut with scissors. Never heard of any applications, though.
  • Powder a condom well with the stuff, and the various bodily fluids wouldn't be able to touch, even in the event of breakage. The question then becomes the toxicity of the spores.

    "No ma'am, it's not a yeast infection...

  • Old News (Score:3)

    by MichielB ( 463280 ) on Thursday June 28, 2001 @07:25AM (#123237)
    I'm sorry, but this is old news. Sciam already posted this a week ago.
    http://www.sciam.com/news/062101/1.html

    Hi everybody by the way. I've been lurking in the science section for quite a while now, and decided to register just now.

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