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Medicine Science Hardware

Micromotors Race About By Turning Water Into Hydrogen Gas 85

MTorrice writes "Microscopic particles of aluminum and gallium rocket around using water as their fuel. The particles, which are 20 micrometers in diameter, are asymmetric: A chemical reaction on the back side of the particle forms hydrogen gas bubbles that propel the motor forward. Over the past several years, bioengineers have built micro- and nanosized rockets that zip through liquids, fueled by chemical reactions between the materials that make up the rockets and their environments. The engineers hope someday these tiny motors could help deliver cargo, such as drugs, in people. Unfortunately, many of these motors require toxic hydrogen peroxide as fuel source, limiting their use in the body. To overcome that constraint, the new micromotors harness a well-known reaction between aluminum and water to produce hydrogen gas."
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Micromotors Race About By Turning Water Into Hydrogen Gas

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  • by snowraver1 ( 1052510 ) on Monday August 27, 2012 @11:08PM (#41145411)
    I don't know bow it's administered, but I'd rather die...
    • Re:20m in diameter (Score:5, Informative)

      by Unknown Lamer ( 78415 ) Works for Slashdot <.clinton. .at. .unknownlamer.org.> on Monday August 27, 2012 @11:16PM (#41145463) Homepage Journal

      Slashdot's lack of unicode support strikes again! There should have been a mu there, oops.

      • Re:20m in diameter (Score:5, Insightful)

        by mark-t ( 151149 ) <markt AT nerdflat DOT com> on Monday August 27, 2012 @11:35PM (#41145543) Journal
        Which raises an excellent point, really. Why does a technical oriented site such as this *NOT* support unicode?
        • Engineering time and it started life as perl written in 1997 by a college student.

          • by ChatHuant ( 801522 ) on Tuesday August 28, 2012 @01:16AM (#41145855)

            Engineering time and it started life as perl written in 1997 by a college student

            That makes sense - how can anybody complete a new feature with only fifteen years of development?

            • I know, right? I mean, if only the supporting platforms slashcode runs on were compatible with Unicode. Why, then instead of cocking up UI with some new Web 2.0 BS, they could have just modified their code to add the feature. ::sigh:: Once again, blame Micro$oft!
            • I wonder if the Geek.net overlords have implemented unicode support at SourceForge or Think Geek.

            • Engineering time and it started life as perl written in 1997 by a college student

              That makes sense - how can anybody complete a new feature with only fifteen years of development?

              True. That's only about as long as Perl 6 has been in development.

        • by Anonymous Coward

          I actually asked CmdrTaco this, and his stupid excuse was, that you couldn't keep things secure with all those special control characters and stuff.

          Which is bullshit, because
          1. ASCII also has control characters (<0x20)
          2. Unicode specifically has a nice separation of types of characters into different blocks. And there are tons of tables online on which are which. Hell, Regex even has complete Unicode-compatible character classes to make this separation. So one only needs to filter all chars in non-allowe

          • I’ve come to the conclusion, that CmdrTaco just doesn't give a shit. (Guess even he considers the site not worth the effort anymore. :/)

            I don't know Perl beyond the basics, but I'm going with a wild guess that, over the years, there's at least some thoroughly tested, debugged and properly secured Unicode libraries out there able to replace whatever crazy REGEX runs behind /.'s code, probably with minimal effort.

            On the other hand, I can also see how converting the huge text database might make things somewhat more difficult, or at least time consuming, take for instance that time when the number of comments hit the 32-bit limit in the DB's i

          • I’ve come to the conclusion, that CmdrTaco just doesn't give a shit. (Guess even he considers the site not worth the effort anymore. :/)

            Yeah... I heard he hasn't even come to office for the past year....

        • Because it is not fun to rewrite your entire codebase to deal with unicode?
          And it is even less fun to rewrite only a part of your codebase if you can't use typechecking to keep the two "domains" apart.

    • Indeed, crossbow, recurve, compound... just seems unnecessary.

      In other words "Ha ha! You were making fun of a type o and you yourself made a type o!"
  • "The particles, which are 20 m in diameter, are asymmetric..."

    Where I come from, 20 meter diameter anythings would rarely be considered particles!

  • by aapold ( 753705 ) on Monday August 27, 2012 @11:32PM (#41145527) Homepage Journal
    ...just not widely reported
    • by DrEnter ( 600510 ) *
      I know it's ridiculous, but my first thought when I read this was an image of over-inflated hospital patients ballooning into the sky and bursting into flames with cries of "oh, the humanity!" I need to watch less TV.
  • by riverat1 ( 1048260 ) on Monday August 27, 2012 @11:35PM (#41145541)

    is this something that could be used to cheaply make hydrogen for fuel? If you put 6.02 * 10^23 of them in water how much hydrogen would it produce?

    • by Ignacio ( 1465 )

      Not enough to replenish the energy consumed by the aluminum production process.

      • by rossdee ( 243626 )

        Speaking of the laws of physics - the GOP are having their convention right now, have they said that they are going to repeal the laws of thermodynamics?

      • by JSBiff ( 87824 )

        How does this compare, efficiency-wise to other processes for hydrogen production? If you had another source of energy (nuclear, solar, etc), and were interested in converting that energy to hydrogen (perhaps to then synthesize something like ammonia or di-methyl ether), would this be an efficient way to go about it?

    • by GoodNewsJimDotCom ( 2244874 ) on Tuesday August 28, 2012 @12:03AM (#41145623)
      You're better off buying an electolyzer for $150-$1000. Electrolyzer required distilled water. Distillers are pretty cheap too, lets say you can get one for 150$.

      Now the cool thing coming out is Toyota's Hydrogen Car for 50k or so in 2015. In order to store hydrogen in a tank, you must first compress it. Hydrogen is a material that erodes a lot of materials it comes in contact with, so dealing with it is somewhat more challenging than other fuels. Compressors exist for hydrogen, but I couldn't find a price for under $12k. Before I become a hobbyist in this, I need to make sure I can afford it, and $12k for the compressor is what makes working on a personal hydrogen refueling station unfeasible for me.

      I think if hydrogen car economy takes off, everyone will have their own refueling station because the only two inputs required are: Electricity and Water. Then you lose some power converting the electricity into hydrogen but being able to store it in fuel tanks as opposed to expensive batteries that wear out makes it nice. We're looking forward to time where people invest in their own solar panels on their property so they pay less in utilities too.

      I think in the short run of a hydrogen economy, you'll have hydrogen refueling stations, but in the long run, people will be making personal stations too. Besides harmless emissions from hydrogen, the cost of fuel will be extremely low compared to gasoline. Of course if the price of the car is greater than the price of a gas powered car and its lifetime of gasoline, there is only going to be a niche market. But if Toyota can get these things for under $25k and they don't have any serious downsides like the electric car's problem of battery arrays dying.... It could be the future.

      Because of this, I want to become a hobbyist, and maybe own my own refueling station some day, but I don't want to get too involved if I can't afford a hydrogen compressor. Anyone know of a place to get a hydrogen compressor for under $12k?
      • by jenningsthecat ( 1525947 ) on Tuesday August 28, 2012 @03:33AM (#41146371)

        Besides harmless emissions from hydrogen, the cost of fuel will be extremely low compared to gasoline.

        Only if the cost of the electricity used to hydrolyze the water is also extrememly low. For the foreseeable future, the only viably-large source of electricity that is close to carbon neutral will likely be nuclear power - sun and wind likely won't be sufficient for a long time. Also, power from sun, wind, and fission are currently priced artificially higher than power from oil, because with oil we're 'borrowing' from future generations to support our extravagant lifestyle but aren't even calculating the principal, never mind the interest...

        I'm all in favour of building 'hydrogen economy' vehicles and infrastructure right now, even though it's not yet clear exactly how we'll come up with enough clean energy to justify it, unless we go all-out nuclear, the prospect of which scares the sh*t out of me. But let's be VERY clear that in the short term we may in fact be increasing carbon emissions by doing so. There are WAY too many people out there who see zero emissions at the tailpipe and think the problem is solved, when in fact total emissions per mile driven may well be higher than those produced by a gasoline engine. Joe Public needs to be educated about such things, and the makers of various 'environmentally friendly' technologies aren't about to do that if it risks harming their sales. We in the tech and scientific communities have an obligation to start getting the word out that There Ain't No Such Thing As A Free Lunch.

      • by codman1 ( 904493 )
        Using Electrolysis is very energy inefficiently, that why its only worth it in certain places eg. over production in nuclear power plants or on very small scales such as Labs. The gallium is used as a catalyst for the reaction the pure aluminium is used and turned into aluminium oxide which can be recycled using the over production of power in nuclear power plants. The other key component is the water which is probably better to use distilled but not critical as any mineral deposits can be reprocessed durin
      • by Kokuyo ( 549451 )

        Instead of stepping up the hydrogen/fuel cell business (which needs two additional conversions of energy), why not just put more effort into better batteries and do away with all that expensive and probably large equipment and put the electricity to work directly?

        I really don't get hydrogen proponents...

        We need three things from batteries:
        - Longer life
        - Faster recharge
        - More storage

        And in a lot of situations, a bit of organizational talent helps to work around some, if not most, of an all electric car's li

        • by Kokuyo ( 549451 )

          I just googled a random factlet: It says, refining a gallon of gasoline uses between 4 and 7.5kWh.

          So a Model S can go 500 km on 85kWh which means it can go 23.5 km per kWh (assuming refining used 'only' 4kWh) and thus per gallon.

          As a comparison, a 2 litre Audi A6 gets 28 MPG. that's about 48 km per gallon.

          So you might say, hey, the gas engines are actually better! You'd be wrong.

          This means that half the electricity a Model S uses, is used anyway by a gas engine! This means, if we switched over to all electr

          • by Kokuyo ( 549451 )

            D'uh, sorry people, I seem to be not quite all there right now... of course it's not 23.5 km per kWh at all... but the per gallon part should be correct, I hope...

        • by gl4ss ( 559668 )

          you still need cheap energy for the both.

          what good is a hydrogen station when cheapest way to get hydrogen is from gasoline??

          • The easiest way is just use electricity off the grid. I've heard, but not confirmed it is around an order of magnitude cheaper than gasoline to electrolyze hydrogen. This sounds reasonable because the electric cars also have cheap fuel from electric.

            Of course if you have a place for a lot of solar/wind farms, they can pay for themselves in 5-10 years with tax credits just on one's own home. So if you're making hydrogen for a refueling station, you could probably charge 1/3 what a gasoline station charg
      • I think if hydrogen car economy takes off, everyone will have their own refueling station because the only two inputs required are: Electricity and Water. Then you lose some power converting the electricity into hydrogen but being able to store it in fuel tanks as opposed to expensive batteries that wear out makes it nice.

        Problem is hydrogen sucks as a fuel. It's not just the density/compression and corrosive problem you described. H2 molecules are tiny - about the smallest molecule there is (only a few

        • by Ignacio ( 1465 )

          What we need is a cheap and cheesy way to make nitromethane in bulk. No idea how, but that would solve several problems at once.

      • by tchall ( 1146319 )

        I think in the short run of a hydrogen economy, you'll have hydrogen refueling stations, but in the long run, people will be making personal stations too. Besides harmless emissions from hydrogen, the cost of fuel will be extremely low compared to gasoline.

        Aside from the unintended consequences of adding tons of water vapor to the atmosphere it's a great idea

        Increasing concentrations of the most powerful greenhouse gas, increased precipitation over the most populous regions of the world, and local climattic changes like Phoenix AZ's humidity increase that no longer allows the use of cheap evaporation coolers... are ALL easily projected results

        Considering that doing this today will require massive use of fossil fuels, and future expansion will require

    • Re:Hydrogen fuel (Score:5, Informative)

      by Solandri ( 704621 ) on Tuesday August 28, 2012 @06:06AM (#41146953)
      There's no such thing as a free lunch. Any energy you hope to get out of burning hydrogen as a fuel has to have been put into it first. The key concept you're looking for is Gibbs Free Energy [wikipedia.org] - a measure of the chemical energy potential of a mole of molecules. H2 and O2 have fairly high Gibbs free energies, while water is very low. So combining H2 and O2 to make H2O releases a lot of energy. But converting H2O back into H2 and O2 requires just as much energy as was released (more in fact, due to inefficiencies). There's no shortcut, as that would violate conservation of energy.

      The only way to cheaply make H2 for fuel is to use substances which start off with high Gibbs free energies. You're probably familiar with many of them - methane, propane, various petroleum products, as well as alcohols and sugars/wood. Converting these substances to H2 for fuel is pretty much the same as burning them in an internal combustion engine, except with additional intermediate steps and huge storage, transportation,and delivery complications. There's an advantage in that there's no pesky carbon, nitrogen, and sulfur in the second step (hydrogen -> water) so we don't get CO2, nitrous oxides, and sulfides as byproducts. But you still need to deal with those byproducts in the first step (fuel -> hydrogen). So it's questionable whether the tradeoff is worth it.

      Incidentally, this is why many people refer to hydrogen as a battery, not a fuel. Raw hydrogen gas is pretty much non-existent on this planet. So you're not getting free energy from the hydrogen. You're taking energy from other sources (burning coal or petroleum, nuclear, hydro, wind, solar) and storing it by converting something into hydrogen gas, then releasing that energy when you burn the hydrogen (well, releasing what's left after efficiency losses). Any energy calculation of the hydrogen economy has to take into account the efficiency losses due to this multi-step conversion process. It's almost bad enough to knock a hydrogen fuel cell car's efficiency down to the efficiency of an ICE gasoline car. (60% efficient fuel cell * 60% efficient hydrolysis = 36% efficiency. Modern ICEs are close to 30% efficient.)

      In TFA's case, the energy used to convert aluminum oxide into metallic aluminum is used to liberate the H2 from the H2O (the Al being converted to Al2O3 by the extra oxygen in the process). So it's almost certainly wasting more energy than if you just did straight electrolysis on the water. The only benefit is that aluminum is very compact and easy to handle as a fuel source, much more so than hydrogen or storing electricity in a battery.
  • by Cylix ( 55374 ) on Monday August 27, 2012 @11:48PM (#41145577) Homepage Journal

    If you've cut yourself at all in the course of these tests, you may have noticed that your blood is pure hydrogen- that's normal. We've been shooting you with an invisible micromotor that's supposed to turn blood into hydrogen, so all that means is it's working.

    • by redback ( 15527 )

      Notice how nobody panics if everything goes according to plan, even if the plan is horrifying

  • I don't think I'd want a bunch of micro-rockets in my blood stream blowing hydrogen bubbles. What happens when I get cut next to someone smoking or a stove with all that hydrogen in my veins?

  • by hkultala ( 69204 ) on Tuesday August 28, 2012 @12:18AM (#41145687)

    argh, again this kind of misleading headline that makes the people who only read the headline think a perpetual machine is finally invented.

    The energy comes from aluminium, aluminium "burning" into aluminium-oxide.

    Putting the "converting water into hydrogen" into headline is misleading reporting.

    • Yeah "converting water into hydrogen by burning aluminum" is a more appropriate summary.

    • "Putting the "converting water into hydrogen" into headline is misleading reporting."

      Yes, but it's great misleading reporting since it implies the fission of oxygen and the fission products all the way down to hydrogen. That's a somewhat endothermic process (cough, cough). Who needs to read the article with that great title?

  • Hydrogen bubbles in your veins can easily be deadly.

  • That's like saying petrol cars run on air. It's not just water, you also need Aluminium.
  • "The engineers hope someday these tiny motors could help deliver cargo, such as drugs. "

    lol. nano-drug-trade. "BTC received, sending off ten billion bots with the coke tonight, expect bell-curve delivery tommorow around noon"

  • Please stop saying things like, "using water for fuel..."!!!!! Water is not fuel any more than the ashes from a wood fire are fuel.
  • Since the world is running out of Helium supplies, it would be nice if scientists could develop ways of generating helium from micromotors.

  • Hey, couldn't these be used as a catalyst to produce hydrogen for use in fuel cells and/or internal combustion engines?

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