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ESA ACT

Giant-Stroke, Superelastic Carbon Nanotube Aerogel Muscles -- Aliev et al. 323 (5921): ... - 0 views

www.sciencemag.org/...1575

BIO NAN actuator materials anisotropic

shared by ESA ACT on 24 Apr 09 - Cached
  • ESA ACT on 24 Apr 09
     
    Looks very interesting: Anisotropic stiffness and tensile strenght, actuation, ...
LeopoldS

Macroscopic invisibility cloaking of visible light : Nature Communications : Nature Pub... - 3 views

www.nature.com/...ncomms1176.html

invisibility PHY science

shared by LeopoldS on 02 Feb 11 - No Cached
  • LeopoldS on 02 Feb 11
     
    and all this without magic metamaterials ...
  • ...1 more comment...
  • Luzi Bergamin on 02 Feb 11
     
    Wellwellwell! I don't know how I have to complain, since I could not yet read the full article, but I'm sure I will :-).
  • Luzi Bergamin on 02 Feb 11
     
    It's funny to see how people get more and more humble in the desperate attempt to save their stupid ideas... At the beginning was the brave and bold aim to cloak something in free space (in a sphere or a cylinder). This requires inhomogeneous, anisotropic, magnetic materials; hopeless!! So one reduces to one polarization, now we have inhomogenous, anisotropic materials; still hopeless! At this point one downgraded the pretension: instead of cloaking in free space, we make a "carpet cloak" and hide an object behind an invisible dent in a mirror. But if that shall be continuous, we still need inhomogeneity and this is very hard. So now instead of a dent we take a cone and then it is claimed to work ... for ONE polarization. But of course the cloak can't work at all incident angles... irony of fate: everything is now made from birefringent media, the antithesis of what the metamaterials dogma was at the beginning!
  • jmlloren on 04 Feb 11
     
    Hi Luzi, can you please send me the paper. We are writing a project based on sulfates and carbonates, and all this BS sounds great for the introduction (The authors used Calcite as birefringent material)
ESA ACT

Surface structure and frictional properties of the skin of the Amazon tree boa Corallus... - 0 views

www.springerlink.com/...7364173l68486347

BIO friction paper locomotion

shared by ESA ACT on 24 Apr 09 - Cached
  • ESA ACT on 24 Apr 09
     
    Anisotropic frictional properties for crawling locomotion.
pandomilla

Bioinspired self-repairing slippery surfaces with pressure-stable omniphobicity : Natur... - 3 views

www.nature.com/...nature10447.html

biomimetics plant self-repairing

shared by pandomilla on 22 Sep 11 - No Cached
LeopoldS liked it
  • a strategy to create self-healing, slippery liquid-infused porous surface(s) (SLIPS) with exceptional liquid- and ice-repellency, pressure stability and enhanced optical transparency. Our approach—inspired by Nepenthes pitcher plants13—is conceptually different from the lotus effect, because we use nano/microstructured substrates to lock in place the infused lubricating fluid. We define the requirements for which the lubricant forms a stable, defect-free and inert ‘slippery’ interface.
  • ts capability to repel various simple and complex liquids (water, hydrocarbons, crude oil and blood),
  • pandomilla on 22 Sep 11
     
    ...This slippery surface was bio-inspired by the carnivorous plant I showed you sometimes ago! I was sure it was a good idea! next time I will be quicker!!
  • ...1 more comment...
  • LeopoldS on 22 Sep 11
     
    Shit. I am sure that there is more to do on this. Let's have a closer look.
  • LeopoldS on 22 Sep 11
     
    And a good lesson that it is important to proceed quickly when you have an idea and don't wait ...
  • pandomilla on 23 Sep 11
     
    Yes, I will see what we could do, but they really did a good job, from the biomimetic of the surface, up to the realization of the material, and the tests...
Luís F. Simões

Pioneer Anomaly Solved By 1970s Computer Graphics Technique - Technology Review - 4 views

www.technologyreview.com/...26589

pioneer anomaly PHY astrophysics

shared by Luís F. Simões on 31 Mar 11 - No Cached
Nicholas Lan liked it
  • Now Frederico Francisco at the Instituto de Plasmas e Fusao Nuclear in Lisbon Portugal, and a few pals, say they've worked out where the thermal calculations went wrong. These guys have redone the calculations using a computer model of not only how the heat is emitted but how it is reflected off the various parts of the spacecraft too. The reflections turn out to be crucial.
  • Ref: arxiv.org/abs/1103.5222: Modelling The Reflective Thermal Contribution To The Acceleration Of The Pioneer Spacecraft
  • santecarloni on 01 Apr 11
     
    This is really cool. I know one of the authors and he is a good guy... the only thing that leaves me unsatisfied is that if the whole issue is related to thermal effects one should have seen the Pioneer effect all the time and not only at about 10 AU... ...or is there some thermal process that kicked in only at this distance?
  • Luís F. Simões on 26 Jul 11
     
    Here's an update on this theory: NASA Releases New Pioneer Anomaly Analysis "The mysterious force acting on the Pioneer spacecraft seems to be falling exponentially. That's a strong clue that on-board heat is to blame, says NASA." Heat emission 'most likely cause' of pioneer anomaly "What's more interesting is that, contrary to the original analysis conducted all those years ago, the deceleration does seem to be decelerating at an exponential rate -- just as one might expect from the radioactive decay of plutonium-238, which powers the two spacecraft. Turyshev concludes, "The most likely cause of the Pioneer anomaly is the anisotropic emission of on-board heat.""
LeopoldS

Phys. Rev. Lett. 107, 126402 (2011): Anisotropic Dirac Fermions in a Bi Square Net of S... - 0 views

prl.aps.org/...e126402

phy science technology NRG

shared by LeopoldS on 13 Oct 11 - No Cached
  • LeopoldS on 13 Oct 11
     
    new wonder material ?
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