From the category archives:

Aim points

Nanomachines, Nanomaterials, and Klm

February 20, 2009

Toward Advanced Nanotechnology: Nanomaterials (5)
My previous post in this series, Nanostructures, Nanomaterials, and Lattice-Scaled Stiffness, explains why the lattice-scaled modulus, Klm, is an important figure of merit: For a set of machines made of different materials, but with similar structures (similar numbers and arrangements of lattice cells), the Klm parameter determines the energy required [...]

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Nanostructures, Nanomaterials,
and Lattice-Scaled Stiffness

February 15, 2009

Toward Advanced Nanotechnology: Nanomaterials (4)

The peg aligns with the hole if the hole is large enough, and the fluctuations are small enough.

In a nanofabrication technology that uses nanomachines to assemble products, the stiffness of the machines is important because it limits the amplitude of thermal fluctuations, yet tolerance for fluctuations is important too. When both [...]

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Toward Advanced Nanotechnology:

Nanomaterials (3)

February 8, 2009

Mechanical engineering meets thermal fluctuations
Thermal fluctuations distort nanoscale structures, and this makes them an enemy of nanotechnologies that rely on precise mechanical motion. Indeed, if one were to set aside design and calculation and instead substitute guesses (I’m not naming guilty parties here), one might suppose that this would prevent nanomechanical engineers from designing reliable [...]

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Toward Affordable Structural DNA Nanotechnology

February 4, 2009

Science recently reported a research advance linked to a series of topics I’ve covered:

Self-assembled systems
George Church’s roadmap for radically lowering the cost of DNA
Structural DNA nanotechnology for modular molecular composite nanosystems
Cryo-electron microscopy for visualizing large self-assembled structures

The advance is an improved structural map of the core of the self-assembled protein machinery that some bacteria use [...]

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Toward Advanced Nanotechnology:

Nanomaterials (2)

January 16, 2009

As every mechanical engineer knows, the stiffness of a material — its elastic modulus — is often a critical property; likewise in nanomechanical engineering, though in part for a different reason. I’d like to say a few words about this, then discuss some materials of interest in implementing nanosystems. And there is something I must [...]

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Toward Advanced Nanotechnology:

Nanomaterials (1)

December 27, 2008

The widespread obsession with diamond nanotechnologies is peculiar: How did the idea of molecular manufacturing, a general approach to organizing mechanosynthesis, been become so closely identified with making diamond?

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The Technology Tree

December 18, 2008

When I look around my office, almost everything I see is either a person, a plant, or the product of machines. If you’re facing a computer screen, very likely your surroundings are similar.

The Forge of Vulcan(detail)

Diego Velázquez

But where did these productive machines come from? With varying degrees of human help, they were themselves made by [...]

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3D imaging of biological nanostructures

December 15, 2008

Deep-etch image of cytoskeleton, with origami inset (upper left)

“Three-dimensional reconstruction of the membrane skeleton at the plasma membrane interface by electron tomography” N Morone et al. JCB, 174:6, 851–862 (2006).

(Inset) “Folding DNA to create nanoscale shapes and patterns”
PWK Rothemund,Nature, 440:297–302 (2006). [pdf]

In an earlier post I mentioned that researchers have been hampered by difficulties with [...]

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