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hormsfield favorited a video
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hormsfield favorited a video
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Noted scientist Stephen Wolfram shares his perspective of how the unexpected results of simple computer experiments have forced him to consider a w...
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Noted scientist Stephen Wolfram shares his perspective of how the unexpected results of simple computer experiments have forced him to consider a whole new way of looking at processes in our universe. Series: "Frontiers of Knowledge" [4/2003] [Science] [Show ID: 7153]
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hormsfield favorited a video
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Sequencia Musical Toccata and Fugue in D Minor do Filme Fantasia.
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hormsfield favorited a video
(3 weeks ago)
This movie produced with Berkeley Lab's TEAM 0.5 microscope shows the growth of a hole and the atomic edge reconstruction in a graphene sheet. An e...
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This movie produced with Berkeley Lab's TEAM 0.5 microscope shows the growth of a hole and the atomic edge reconstruction in a graphene sheet. An electron beam focused to a spot on the sheet blows out the exposed carbon atoms to make the hole. The carbon atoms then reposition themselves to find a stable configuration
http://newscenter.lbl.gov/press-relea...
BERKELEY, CA — Science fiction fans still have another two months of waiting for the new Star Trek movie, but fans of actual science can feast their eyes now on the first movie ever of carbon atoms moving along the edge of a graphene crystal. Given that graphene single-layered sheets of carbon atoms arranged like chicken wire may hold the key to the future of the electronics industry, the audience for this new science movie might also reach blockbuster proportions.
Researchers with the U.S. Department of Energys Lawrence Berkeley National Laboratory (Berkeley Lab), working with TEAM 0.5, the worlds most powerful transmission electron microscope, have made a movie that shows in real-time carbon atoms repositioning themselves around the edge of a hole that was punched into a graphene sheet. Viewers can observe how chemical bonds break and form as the suddenly volatile atoms are driven to find a stable configuration. This is the first ever live recording of the dynamics of carbon atoms in graphene.
The atom-by-atom growth or shrinking of crystals is one of the most fundamental problems of solid state physics, but is especially critical for nanoscale systems where the addition or subtraction of even a single atom can have dramatic consequences for mechanical, optical, electronic, thermal and magnetic properties of the material, said physicist Alex Zettl who led this research. The ability to see individual atoms move around in real time and to see how the atomic configuration evolves and influences system properties is somewhat akin to a biologist being able to watch as cells divide and a higher order structure with complex functionality evolves.
Zettl holds joint appointments with Berkeley Labs Materials Sciences Division (MSD) and the Physics Department at the University of California (UC) Berkeley, where he is the director of the Center of Integrated Nanomechanical Systems. He is the principal author of a paper describing this work which appears in the March 27, 2009 issue of the journal Science. The paper is entitled, Graphene at the Edge: Stability and Dynamics. Co-authoring this paper with Zettl were Çağlar Girit, Jannik Meyer, Rolf Erni, Marta Rossell, Christian Kisielowski, Li Yang, Cheol-Hwan Park, Michael Crommie, Marvin Cohen and Steven Louie.
This Quick Time movie produced with the TEAM 0.5 microscope shows the growth of a hole and the atomic edge reconstruction in a graphene sheet. An electron beam focused to a spot on the sheet blows out the exposed carbon atoms to make the hole. The carbon atoms then reposition themselves to find a stable configuration.
In their paper, the authors credit the unique capabilities of TEAM 0.5 for making their movie possible. TEAM stands for Transmission Electron Aberration-corrected Microscope. The newest instrument at Berkeley Labs National Center for Electron Microscopy (NCEM) - a DOE national user facility and the countrys premier center for electron microscopy and microcharacterization - TEAM 0.5 is capable of producing images with half angstrom resolution, which is less than the diameter of a single hydrogen atom.
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hormsfield favorited a video
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Scientists in Sweden film the sub-atomic particle, the electron, for the first time. An electron is approximately 1867 times smaller than a proton ...
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Scientists in Sweden film the sub-atomic particle, the electron, for the first time. An electron is approximately 1867 times smaller than a proton and is constantly moving.
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