Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×
Medicine Science

Sticky Tape Found To Emit Terahertz Radiation 96

An anonymous reader writes with this excerpt from New Scientist "'Peeling sticky tape has already been shown to produce X-rays, so Joseph Horvat and Roger Lewis of the University of Wollongong in New South Wales, Australia, tried to see if it could create lower-frequency terahertz radiation. "We were rather pleasantly surprised to obtain a clear signal in our first attempt," says Horvat. Strongly adhesive Scotch Magic 810 tape and weakly adhesive electrical tape both yielded strong terahertz signals, ranging from 0.1 to 10 terahertz, but only about a microwatt of power, too little for practical use (Optics Letters, vol 34, p 2195). Horvat says that refinements should increase the power by orders of magnitude.' It may be old news to Slashdot that [peeling clear tape] had been proved to produce X-rays, but watching the linked video where they use tape to expose X-ray film was pretty amazing."
This discussion has been archived. No new comments can be posted.

Sticky Tape Found To Emit Terahertz Radiation

Comments Filter:
  • by russotto ( 537200 ) on Wednesday August 05, 2009 @03:10PM (#28961531) Journal

    From now on, it's staples for everything.

  • i've been using it to cook my meals for YEARS
  • Duct tape? (Score:3, Funny)

    by jeffshoaf ( 611794 ) * on Wednesday August 05, 2009 @03:18PM (#28961629)
    So, does peeling duct tape emit gamma bursts?
    • Re:Duct tape? (Score:5, Informative)

      by ae1294 ( 1547521 ) on Wednesday August 05, 2009 @03:25PM (#28961721) Journal

      So, does peeling duct tape emit gamma bursts?

      Do you really honestly want to know the answer to that question?

      I, for one, enjoy my duct-tape and don't want a surgeon general's warning and government taxes on it...

      • So, does peeling duct tape emit gamma bursts?

        Do you really honestly want to know the answer to that question?

        HULK WANT ANSWER! WHEN HULK PEEL TAPE, HULK GET STRONGER!

    • So, does peeling duct tape emit gamma bursts?

      Yes! It's how the Fantastic Four got their powers.
      Also,
      WARNING: Do not look into Stick Tape with remaining eye!

  • by swb ( 14022 ) on Wednesday August 05, 2009 @03:19PM (#28961651)

    Is there a practical application for this? Does mechanically peeling tape require less power than producing the same radiation through more conventional means or with simpler materials?

    I can appreciate the gee-whiz nature of it but I can't quite figure out what value it has outside of the sciencey aspect of it.

    • by FooAtWFU ( 699187 ) on Wednesday August 05, 2009 @03:32PM (#28961801) Homepage
      Making X-rays (and terahertzes) currently requires expensive power-hungry inefficient particle accelerators. These advances might lead to cheaper X-ray machines (and terahertz radiation machines, whatever you use that for) which just require a disposable/replaceable tape cartridges. This has implications for medicine and science, particularly in developing countries.
      • Terahertz sources don't require particle accelerators. See my post above ("Terahertz generation is an interesting problem".)
      • by icebike ( 68054 )

        So next visit to a cheat dentist might leave me beardless you say?

      • Or rather, we would more likely see x-ray lasers which increase the horrible power efficiency and production cost. X-ray's right now are generated in all directions and only sent in one direction throuhg basically a pinhole. A lot of expensive equipment is also made to make sure it doesn't overheat and to make sure that you get a sort of clean spectrum.
      • These advances might lead to cheaper X-ray machines (and terahertz radiation machines, whatever you use that for) which just require a disposable/replaceable tape cartridges.

        The machines might become cheaper, but the carts will be the big money maker, if say, Lexmark is making them.

        • Depressingly true. I blame Ford, wasn't it him that said "if I could be the only supplier of gasoline, I'd give my cars away for free"?

          Actually, the real reason I'm replying is to salute the History of the World Part 1 quote in your signature.
          Everything's so GREEEEEEN!
      • by sjames ( 1099 )

        and terahertz radiation machines, whatever you use that for

        That's what the pervs in the TSA want to use to look under your children's clothes.

    • by dissy ( 172727 )

      I can appreciate the gee-whiz nature of it but I can't quite figure out what value it has outside of the sciencey aspect of it.

      At this stage of the game, the only value is the knowledge itself that this effect exists.
      No other value what so ever at the moment.

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      A reusable version of tape that emits X-rays and/or terahertz radiation would be great, actually. A rudimentary prototype could be just a continuous, long loop of tape that runs around a series of non-adhesive pulleys; it then loops around one pulley specifically designed to stick to the tape, then un-adhere without removing or contaminating the adhesive.

      In some ways, radiation-emitting tape reminds me of the spark gap transmitter, except we're going backwards in technology from the X-ray tube, sorta.

    • Generating terahertz radiation, especially coherent Terahertz radiation, is hard because the frequency (around 300GHz - 20THz) is too low for conventional solid-state laser technology and too high for conventional electronic antennas. And it is potentially useful for a range of applications such as nondestructive high-resolution imaging (for e.g. materials, medical, and security applications), spectroscopy, or opening up new communications bandwidths. (Google "terahertz applications" [google.com] and you'll find a lot of links.)

      There are a number of terahertz sources that are becoming available, from optical rectification schemes to free-electron lasers, but they have a tendency to be bulky and inefficient, so a lot of researchers are looking for alternative generation schemes.

      That being said, I suspect that the terahertz radiation produced by sticky tape is incoherent, which would severely limit its utility in practical applications. (Quite apart from the efficiency, which sounds like it is currently very low.) That doesn't mean that it isn't interesting from a basic science perspective, of course.

      • though this does beg the question, what is it about tape that causes this emission? i know _very_ little on the subject but to me it seems there must be some chemical reaction occurring when the adhesive is being forced to lose adhesion, if not a reaction, some sort of molecular stress causing particle loss? again, having no professional background at all this is mere armchair speculation, but the notion of a chemical compound being the cause of this sort of generation is potentially very valuable. In the s

        • Don't take this as a personal criticism, because it's not... For those who want to properly use the phrase "Beg the Question" though, here's a fun explanation:

          http://www.qwantz.com/index.php?comic=693 [qwantz.com]

          • this begs the question, are you a pedantic basement dweller? ;) i thought the question was implicit as he raised the the issue of creating terahertz coherency. so to my (admittedly not infallible) logic this logically begs the question of whether or not this new method of terahertz generation could be harnessed for this application.

            i could be wrong, but hell, whats life without a few grammatical errors and malapropisms?

  • But can it give me super powers!?
    • by ArsonSmith ( 13997 ) on Wednesday August 05, 2009 @03:24PM (#28961715) Journal

      Yes, you will have the power to mend small tears in sheets of paper. The magical ability to control paint to be applied in some areas but not in others along nice sharp lines. The super human ability to stop electricity from shorting between two wires.

      Among other similar powers.

    • by hAckz0r ( 989977 )
      No, but depending on what you are pulling the tape off, or how fast, of you might get some evil nemesis of yours to do exactly what you ask of them.
  • Terahertz radiation (Score:4, Interesting)

    by hAckz0r ( 989977 ) on Wednesday August 05, 2009 @03:21PM (#28961689)
    Doesn't sound odd to me at all. Last time I checked EVERYTHING emanated something in the Terahertz region of the spectrum. Its like infra-red in that its darn hard not to give off a signature of some kind. That's how you can use it in the airports for monitoring for hidden weapons without dousing people with all kinds of xrays. Things that are more dense give off more T-waves. If you peal tape off something it causes a release of energy, and part of that will be thermal, and part T-waves.
    • by IorDMUX ( 870522 ) <mark DOT zimmerman3 AT gmail DOT com> on Wednesday August 05, 2009 @03:50PM (#28962059) Homepage

      Its like infra-red in that its darn hard not to give off a signature of some kind. That's how you can use it in the airports for monitoring for hidden weapons without dousing people with all kinds of xrays.

      Actually, terahertz radiation security monitoring works just like current x-ray monitoring at airports. In other words, they have a source on one side and a receiver on the other, and they look for anything blocking the radiation. THz radiation penetrates fabrics, plastics, and mostly flesh, but is non-ionizing (unlike x-rays), so it is an ideal choice to see what someone is carrying without asking them to strip down, first.

      THz security systems do *not* rely on the natural emissions of objects. The power contained in this band is quite small and difficult to use. Additionally, the power radiated from an object is *not* dependent on density, but, like all thermal radiation, dependent on the heat of the object.

      It is a silhouette based detection--like a photograph or an x-ray--not an emission based detection, such as a Geiger counter detecting radioactive material.

      • by IorDMUX ( 870522 )

        THz radiation penetrates [...] mostly flesh

        My mistake. THz radiation does not penetrate water, so flesh would appear generally opaque.

      • Re: (Score:3, Informative)

        by Anonymous Coward

        Actually, the current detectors appear to be reflective rather than transmissive. Since human flesh is generally opaque to terahertz waves, and human bodies are full of little cavities that don't show up in silhouette, it would be pretty simple to hide something from a transmissive detector.

        X-rays work as transmissive detectors because the majority of the body is mostly transparent to them. It decreases the noise when you are looking for metal objects.

        • by IorDMUX ( 870522 )
          Good catch there... sorry, I was trying to differentiate between active and passive detectors, of which both transmissive and reflective detectors are active detectors, while the OP posited a passive detector.
    • So I can't use it to do a cheap, do-it-yourself CAT-scan?
  • Terminology (Score:5, Funny)

    by 93 Escort Wagon ( 326346 ) on Wednesday August 05, 2009 @03:22PM (#28961697)

    Strongly adhesive Scotch Magic 810 tape and weakly adhesive electrical tape both yielded strong terahertz signals,

    I propose that we add two new fundamental forces to our physics lexicon - "strongly adhesive" and "weakly adhesive".

    • Re: (Score:2, Interesting)

      by pete-classic ( 75983 )

      I've been working on a grand unified theory of adhesion for years. My calculations predicted sticky threads on message boards.

      I'm currently seeking funding for my duct tape accelerator. I don't think the EU is going to be fooled twice, though.

      -Peter

      • I'm currently seeking funding for my duct tape accelerator. I don't think the EU is going to be fooled twice, though.

        -Peter

        What if CERN combined your duct tape accelerator with the LHC? Then we could have one working accelerator!

  • Not to be a troll, but who cares? I read TFA, which was basically just a shallow page to link to the original PDF article, for which they want me to pay $35 to read. There was some vague talk of how it might help "Medical Lasers" (Sharks?), but nothing substantial.
    There's no discussion of application, and no discussion of how the experiment was performed. I suppose that I take it on faith that cows really do fart methane, and I'll have to take it on faith that tape really does fart terahertz radiation.
    • by mcgrew ( 92797 )

      I read TFA

      Ewe muss bee knew hear!

      I suppose that I take it on faith that cows really do fart methane

      You can test this yourself with a mass spectrometer. All farts are methane; that's why you can light 'em. Cow farts, cat farts, people farts, etc. That smell that shit produces is methane and bacteria.

      But thirty five bucks to RTFA? WTF? I just did a google news search on "sticky tape Terahertz Radiation" and got ONE result - TFA.

      • But thirty five bucks to RTFA? WTF? I just did a google news search on "sticky tape Terahertz Radiation" and got ONE result - TFA.

        Yeah. Inside it links to this:
        http://www.opticsinfobase.org/abstract.cfm?URI=ol-34-14-2195 [opticsinfobase.org]
        With words like "tribocharging" and "bremsstrahlung", I'm really on the edge of getting my credit card out right now. Or, second thought, maybe I'll just wander over to youtube and see if I can get confirmation of your "you can light'em" explanation.

        • Well, triboelectricity is generated by rubbing/crushing things like when you chomp down on wintergreen lifesavers and sparks shoot off of them.

          Bremsstrahlung is German for slowing/braking, therefore bremsstrahlung radiation is given off when electrons lose energy while being decelerated.

          At least that's what I remember from Physics 101 25 years ago.

          • by Forbman ( 794277 )

            well, Bremsstrahlung came about due to what happens in a cyclotron - as the electrons are bent around their circular orbit, they of course emit Xrays. There are some cyclotron/synchrotrons that aren't entirely circular for their entire orbit, but more polygonal with rounded corners, and each corner is a testing station where objects can be exposed to the bremsstrahlung radiation. One obvious use is for high-intensity, high-frequency Xray imaging (lower diffraction, finer resolution, etc)...

            • Not quite.

              The radiation that is emitted by the beam being bent around the synchrotron is actually called synchrotron radiation. Bremsstrahlung is a similar process where charged particles emit radiation when decelerated.

              The physics is approximately the same (the acceleration -- transversely in the case of synchrotron radiation, and longitudinally in the case of bremstrahlung -- causes a reorganisation of the field lines of the particle), however they are given different names to distinguish their somewhat

      • Re:So What? (Score:4, Informative)

        by MaskedSlacker ( 911878 ) on Wednesday August 05, 2009 @03:56PM (#28962151)

        You can test this yourself with a mass spectrometer. All farts are methane; that's why you can light 'em. Cow farts, cat farts, people farts, etc. That smell that shit produces is methane and bacteria.

        Methane is odorless, so no. And that is not the only factual error in your post. Methane is uncommon in flatulence (most livestock methane emissions are from belching, not farting). Most flatulence is nitrogen, and carbon dioxide. The smell comes from volatile organic acids and reduced sulfur compounds produced in protein breakdown.

        TLDR version: You're talking out of your ass, and it stinks because you eat too much meat.

  • The blanket on my bed (don't know what it's made of) emits sparks, especially when the air is dry (like winter when I use it). I wonder what other radiation/photons it emits besides visible light?

    Does sticky tape cause cancer?

    • by dissy ( 172727 )

      The blanket on my bed (don't know what it's made of) emits sparks, especially when the air is dry (like winter when I use it). I wonder what other radiation/photons it emits besides visible light?

      The blanket, just like everything else made of matter and involving energy reactions, will mainly emit high frequency radiation such as this, and low frequency radiation known as infrared (or in laymen terms, 'heat')

      Does sticky tape cause cancer?

      In the sense that everything made of matter emits radiation, yes.

      Though at the rate of decay, you would need to be exposed for a couple tens of thousands or millions of years to get a dose roughly 1% of a chest x-ray. Odds are your cells will stop functioning due to other causes long before tha

      • by schon ( 31600 )

        everything made of matter emits radiation

        Eeep!
         
        /me dons tinfoil hat.
        /me realizes tinfoil is matter

        D'oh!

        • Re: (Score:3, Funny)

          Eeep! /me dons tinfoil hat. /me realizes tinfoil is matter

          D'oh!

          I don't know if I should fear or welcome the day conspiracy theorists spontaneously all decide that tinfoil is out to get them.

    • The blanket on my bed (don't know what it's made of) emits sparks, especially when the air is dry (like winter when I use it). I wonder what other radiation/photons it emits besides visible light?

      Does sticky tape cause cancer?

      Since the tape needed to be peeled in a vacuum to produce x-rays rather than visible light, I assume that it needed to again be done in a vacuum to produce "lower-frequency terahertz radiation". I'm guessing that if you are peeling tape in a vacuum, you have more immediate concerns than cancer.

      • by jddj ( 1085169 )

        I've actually tried to peel tape in a vacuum, but I couldn't get the bag to seal around my wrists. Too dusty - cat dander and hairs and stuff. Got all over everything.

    • The blanket on my bed (don't know what it's made of) emits sparks, especially when the air is dry (like winter when I use it)

      Erm... that's static electricity.

      • by mcgrew ( 92797 )

        Yes, but the question is, what frequencies do these tiny lightning bolts emit besides visible light?

  • by IorDMUX ( 870522 ) <mark DOT zimmerman3 AT gmail DOT com> on Wednesday August 05, 2009 @03:31PM (#28961789) Homepage
    If anyone is curious about how this happens, it is due to the very high voltages developed on clear sticky-tape when it is unrolled. The peeling action tends to create a very uneven distribution of charges on the tape surface... the tape itself is a wonderful insulator, and as a result the charges cannot easily snap back to equilibrium states.

    This causes very high voltages and, where the tape is just being unrolled from the roll, extreme electric field as the distance is so small. (Remember, Electric field is measured in V/m!). Charges arc through the air easier than they can travel through the tape, so you get all sorts of emissions from this miniature lightning storm as the voltage drops back to a static level of 'only' about a kV.

    Incidentally, this is why you should always use special ESD-approved tape when working anywhere around electrostatic-discharge-sensitive devices. My company's ESD training class had some quite interesting demonstrations where stuff was destroyed with a single piece of freshly unrolled tape. Unfortunately for me, I had yet to learn that lesson in graduate school, and so I ruined many a sensitive analog ASIC by taping a supposedly protective dust cover over the bare IC* (we were too cheap to pay for the black packaging that most people call a "chip"). :-(

    *Note to all the pedants out there: Yes, a fabricated IC has its own natural shield of silicon dioxide (glass) on top of the deposited layers, however the tens-of-micron-thin wire bonds that connected the IC to my prototyping board were exposed to air, and could easily be broken--or worse, shorted--by errant dust particles.
    • Thank you. You're officially smarter than the article. Unfortunatley, Can't mod this informative, because I've already posted... (See "So What" above)...
    • by IorDMUX ( 870522 ) <mark DOT zimmerman3 AT gmail DOT com> on Wednesday August 05, 2009 @03:36PM (#28961875) Homepage

      you get all sorts of emissions from this miniature lightning storm

      Just to clarify my own post:

      The emissions don't come from the electric field itself, but from the electrons, accelerated to a very high velocity, ramming into things like air molecules and the other strip of tape. The high energies imparted to the electrons on the receiving end of these collisions allows for emission of very low-wavelength photons (terahertz radiation, x-rays) as the electrons drop back to their natural states.

      • by chaim79 ( 898507 )

        From the original article (second link) it says this only works in a vacuum, with air present unrolling tape does not produce any X-Rays. I would suspect that this is because Air is less of an insulator than tape, and can reduce the energy involved to levels below the threshold for creating X-Rays...

        However, that's only a guess...

    • Hmm... speaking of which, I wonder if there might be a practical use of this by combining it with a tesla coil setup. (Instead of a loop, have a series of brushes contacting the smooth side of the sticky tape right at the point where the sticky side of the tape separates from the spool, only done at high speed.

  • by Stu101 ( 1031686 ) on Wednesday August 05, 2009 @03:41PM (#28961937) Homepage

    I can see al qaeda ordering boat loads of it for a mass suicide tape pulling! Does this also mean tape may be declared a weapon of mass destruction ;)

    • Re: (Score:3, Funny)

      by StikyPad ( 445176 )

      Laugh it up, fuzzball! Some of us are worried that *we* might get caught up in this dragnet just because our names sound adhesive..

  • Putting sticky tape on my glasses as we speak.
  • IANANP 'n I'm just ask'n but could this be a solution to Large Hadron Collider Struggling [slashdot.org] ? We all know if it weren't for Einstein running at the speed of light while shaving we wouldn't even have a Special Theory of Relativity. But like I said I'm just throw'n the idea out there.
  • It hurts terribly when you peel off a Band-Aid

  • ...or is it the GREATEST discovery?
  • "...it could create lower-frequency terahertz radiation."
    Isn't tera 10 to the 12th? Would that not be high frequency radiation? It sits between Microwaves and Infrared.

    • by Arimus ( 198136 )

      Err... X-Rays are 3x10^16 to 3x10^19 so terahertz radiation is lower relative to x-rays.

  • I've noticed that if you peel tape in low light, you can see a blue glow as the tape separates (try it for yourself). I wonder though, if this simply a static electrical discharge or evidence of something more going on?

  • which should be obvious to any slashdot reader:

    fusion power from sticky tape!

    (give me funding)

  • Check out this nice article:

    http://pages.towson.edu/ladon/wg/candywww.htm#SciAmer [towson.edu]
    (also see the wikipedia page: http://en.wikipedia.org/wiki/Triboluminescence [wikipedia.org])
    Article says sugar's light emission on crystal breaking is lightning on a small scale, charge separation causing electrons to jump and nitrogen emission. Doesn't describe x-rays or use of vacuum.

    I am wondering:

    - Could an x-ray or terahertz wave guide be included somehow in the adhesive used
    - Would striking rocks against each other, or a cigaret

  • I process my own film and have always noticed, especially with TMAX B&W 120 rolls that - when I finish loading the film into the development spool - as I peel off the tape holding it onto the original film spool, I can see "stars" sparkle as it's peeled. Of course this is done in total darkness (no red light) and after my eyes have fully dilated in the pitch black. Also helps to not look directly at it but slightly to the side because highly sensitive rods in the eye are concentrated around the perimete

    • Fogging of film by peeling the adhesive tape has been well-known for years. I usually cut the end off with scissors rather than peeling.

      Similarly, one should be cautious about rewinding film too quickly in the camera, and in unrolling and reeling film in the darkroom, especially in dry conditions.

      If one can even find film, of course.

      My favorite is using a Breathe Right strip with dark-acclimated vision. Peeling the wrapper open emits light, as does peeling the backing paper off the strip.

      How long

  • A microwatt terahertz radiation would be a great thing. That made me check their paper. In the Optics Letters the authors just write they had " 1 microwatt", which became "about a microwatt of power" in the linked blog. The maximum really measured was just 0.1 nW. Even assuming that they can focus only 1% of the THz radiation on the detector (I didn't find them specifying it) it seems to be *much* less than 1 microwatt.

Love may laugh at locksmiths, but he has a profound respect for money bags. -- Sidney Paternoster, "The Folly of the Wise"

Working...