Nanotech Motors, Biotransistors, DNA Fractals

FleaPlus writes "The American Institute of Physics has a news bulletin describing a couple of interesting nanotech advances. The first is the smallest electric motor in the world, made by Alex Zettl's group at UC Berkeley. The second is a single-protein wet biotransistor. Additionally, Technology Research News reports on algorithmic self-assembly of DNA Sierpinski triangles, by Erik Winfree's group at Caltech."

Comments

Eventually...

[A Sea and Cake]

The first is the smallest electric motor in the world, made by Alex Zettl's group at UC Berkeley. Eventually, this will go into the world's smallest electric planer, which will be used, in part, to create the world's smallest violin. Tragically, this wonder of design will be crushed between the fingers of Steve Buscemi.

Re:Eventually...

[karvind]

At Cornell we already made the Nanoguitar and Nano saxophone. Yes we were working on the nanodrums these days. No applications for auditions, we use very fast pulse lasers only :)

Nanoelectromechanical relaxation oscillator

[katana]

Okay, I'm not a scientist, but why would you want a *smaller* vibrating dildo?

Re:Coral Cache

[Capt'n Hector]

Berkeley has a 4xOC48 line last I heard. NYU will go down before Berkeley does...

How does it work ?

[karvind]

The peak pulsed power is 20 microwatts. Considering that the device is less than 200 nm on a side, the power density works out to about 100 million times that of the 225 hp V6 engine in a Toyota Camry.

I am not sure if I understand the power density claims. Here is a simple calculation. 20 microwatts in cube of 200nm x 200nm x 200nm will be 20 microwatts in 8 x 10^(-15) cm^3 volume. That will be a power density of 2.5 x 10^9 Watts/cm^3.

Sun's fusion power density is only ~ 2.5x10^(-4) Watts/cm^3 with core temperature around 15.7 x 10^6 K. I can understand that we wouldn't be generating the heat at peak density, but if we generate that high power desnity in nanomechanical system for even any reasonable time - wouldn't it just evaporate unless we find a very fast way of removing the power efficiently ?

definition of "nano-"

[bcrowell]

Nanotechnology has gotten a reputation for being a flaky area of research. Part of the problem is that the word "nanotech" sounds cool, so people tend to use it without defining what they mean. Eric Drexler originally defined it in terms of machines that worked at the molecular level, i.e., on scales of a few nanometers. The problem is that there are fundamental reasons why it's extremely difficult to construct machines on that scale, and in the 20 years since he published Engines of Creation, basically nothing has happened to realize his original vision. Meanwhile, people have been making smaller and smaller machines via techniques that would never be able to scale down to the scales Drexler had in mind. The wikipedia article distinguishes between "nanotechnology" and "molecular nanotechnology." The Berkeley group's motor, for instance, is clearly on a scale (hundreds of nm) that is not molecular nanotechnology.

The DNA trick is particularly disappointing

[Artifakt]

At first, I thought the DNA assembly-Sierpinski Triangle story was particularly interesting, as a link between real world information storage and the usually unworldly area of fractal geometry. On following the story, it turns out that the error rate is simply enormous (1 to 10%). DNA, in normal use, works about a billion times more reliably than it does here.
You could probably coax DNA to assemble into face centered cubic crystals with a much lower error rate than that. Hell, you might be able to get little figures of Snoopy and Garfield more reliably than these Sierpinski Triangles. This is like proving you could workably rebuild the Golden Gate bridge from Mayonaise and save the tax-payers a fortune, for sufficiently low values of "workable","fortune", and probably "Mayo".

Re:The DNA trick is particularly disappointing

[xEndymionx]

the error rate is actually rather low, the high number reported comes from error propagation. if you get a single site error, the next generation of cells below it will be computed using that error, and will thus also be erroneous. the actual number of genuine errors is rather small. winfree also has done work in error-correcting self assembly of wang tiles (which is what this really is). the key point to his generating the sierpinski gasket is that it proves that one can computer elemetary cellular automata with this dna blocks, and that includes eca rule 110, which has been proven to be universal by matthew cook. dr. winfree gave a talk about all these findings early last semester at my university.