Recent content by Stanley514

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    Massless fermions Klein tunneling

    But they claim created graphene tunneling diode in which quasiparticles(?) tunnel through dielectric barrier (just few atoms thick). How do you explain that? QUOTE: Here we report resonant tunnelling of Dirac fermions through a boron nitride barrier, a few atomic layers thick, sandwiched...
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    Massless fermions Klein tunneling

    So, Klein tunneling (of electrons or charged quasiparticles) through the air is not possible under any practical conditions? This one article mentions Photonic Klein tunneling through a dielectric slab. http://arxiv.org/pdf/1101.3519.pdf And if it would be possible, what distance could we...
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    Can a plane without wings fly?

    True. But helicopters have worse efficiency than planes, don't they?
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    Massless fermions Klein tunneling

    1) Could this quasiparticles carry energy or information while they tunnel? 2) Could you use just an empty air as a dielectric (in principle)? 3) If they Klain-tunneling through a dielectric barrier, what maximal thickness of such barrier could be acheived?
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    Massless fermions Klein tunneling

    So, graphene quasiparticles could tunnel through any kind of electric barrier (electric field?), but through dielectric barrier they tunnel on very small distance only, like regular tunneling particles?
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    Massless fermions Klein tunneling

    They claim they created graphene tunneling diode with very thing layer of dielectric between graphene sheets. http://www.researchgate.net/publication/260520206_High_performance_vertical_tunneling_diodes_using_graphenehexagonal_boron_nitridegraphene_hetero-structure If electrons tunnel through...
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    Massless fermions Klein tunneling

    QUOTE: "In 1929, physicist Oskar Klein[1] obtained a surprising result by applying the Dirac equation to the familiar problem of electron scattering from a potential barrier. In nonrelativistic quantum mechanics, electron tunneling into a barrier is observed, with exponential damping. However...
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    Gases compression at critical point. LNG (Methane) storage.

    What is known about methane solubility in supercritical fluids (SF)? It is claimed SF are excellent as a solvents. Is there some exact data on how many volumes of methane you could solve in a record SF?
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    Gases compression at critical point. LNG (Methane) storage.

    :smile: It could be, but nowdays they find and synthesise more and more substances with really unusual properties...
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    Gases compression at critical point. LNG (Methane) storage.

    I meant some kind of liquid long chaned hydrocarbons similar to polyethilene by molecular mass and carbon chain length. Adsorbents do not provide better energy density than CNG. And adsorbent degrade pretty fast. I meant storing methane in solved rather than adsorbed form. For example if you...
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    Gases compression at critical point. LNG (Methane) storage.

    Well, I mean, if we compress water at 20 C to 100 atm it will rise its boiling point to 309 C. 280 C more up. But if we compress liquid methane at -164 C to 100 atm it will not rise its boiling point to +20 C. Not even to -80C (below its critical temperature). Because if it would we would be...
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    Gases compression at critical point. LNG (Methane) storage.

    To store methane at ambient temperature and pressure in liquid form we need to increase its boiling point up 200 C. If you pressurise water to 100 atm. it will rise its boiling point more than 200 C. Why the same thing doesn't work with methane? Is there some chemical additives which could...
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    Gases compression at critical point. LNG (Methane) storage.

    I thougt that pressurising gas near critical point and pressure relieves you from need to maintain pressure after gas been liquefied. So, for example you compressed methane at -82 and 45 atm. to 1000 atm. and reduced pressure again to 45 atm. You do not need to maintain pressure of 1000 atm...
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    Gases compression at critical point. LNG (Methane) storage.

    There are claims or at least assumptions that: "upon approaching "critical point" pure gases become super compressible. You could compress them many times without pressure increase and store like this if you maintain exact temperature and pressure needed. It opens possibility to superdense gas...
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    Electron-positron pair production

    But if you need no energy to maintain electrostatic field, in principle, and this field creates positrons and electrons from ''nothingless'' and these positrons have real energy and could annihilate with something releasing gamma rays, wouldn't it mean we received energy from physical vacuum?
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