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8/21/2006: Close-up of the world's sharpest man-made item
axlrosen finds it here and I think it was boing boingd as well.
Looks huge to us in this image, but this is a tungsten needle: so sharp that the individual round globe-like things you see there are individual tungsten atoms. From the article linked at the source,
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The Sharpest object yet made is a tungsten needle tapering down to about the thickness of single atom. The needle, made by postdoc Moh'd Rezeq in the group of Robert Wolkow at the University of Alberta and the National Institute for Nanotechnology, starts out much blunter. Exposed to a pure nitrogen atmosphere, however, a rapid slimming begins. To start with the tungsten is chemically very reactive and the nitrogen roughens the tungsten surface. But at the tip, where the electric field created by applying a voltage to the tungsten is at its maximum, N2 molecules are driven away. This process reaches an equilibrium condition in which the point is very sharp. |
It all seems very impressive, but I don't have a good physics background. All I know is, the next time somebody calls me "needle dick", I'll have a really good comeback: tungsten needle dick.
(Oh please, a dick joke is always appropriate. I'm uncouth, or something.)
Bullitt Monday Aug 21 01:27 PM
an electric tungtsen needle dick for that matter
AureliusVin Monday Aug 21 01:44 PM
I wonder, you would even feel the needle if it were to penetrate your skin?
axlrosen Monday Aug 21 02:06 PM
Look out - it's Nano-Snakes on a Plane!!
Elspode Monday Aug 21 05:59 PM
Okay, I'll bite. If atoms are whirling fields of nuclear particles...and they are...then how can we "see" an individual atom?
The 42 Monday Aug 21 06:31 PM
| Okay, I'll bite. If atoms are whirling fields of nuclear particles...and they are...then how can we "see" an individual atom? |
Think about it this way: Of course we have to be able to see atoms- if you can't see atoms you can't see anything, and obviously there is such a thing as sight, so we must be able to see atoms.
xant Monday Aug 21 06:48 PM
It's all probability. You're seeing where matter probably is, most of the time (it was there at some point, or it wouldn't have been imaged). That's all you *ever* see, it's just that it's easier to grasp the probabilities involved when you're looking at a single atom.
capnhowdy Monday Aug 21 07:30 PM
I think it's a jelly monster.
pdaoust Monday Aug 21 07:49 PM
lumpies
I think the reason we see them as lumps is that this photo was probably taken with a scanning tunneling microscope. It can resolve to the atomic level, each atom appearing as a foggy gray dot (I believe the image is created by measuring the density of electrons, which of course is greater around an atom). I'm guessing that they took the STM image and applied a few Photoshop filters to make it look way more wickeder.
capnhowdy Monday Aug 21 08:26 PM
heehee... more wickeder. Catchy!
xoxoxoBruce Monday Aug 21 09:17 PM
Ah-ha, so that's what the needles are used for.
According to Bob Wolkow, up in The Great White North(Alberta), quoted in The American Institute of Physics publication, Physics News Update;
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The probe tips used in scanning tunneling microscopes (STMs), even though they produce atomic-resolution pictures of atoms sitting on the top layer of a solid material, are not themselves atomically thin. Rather their radius of curvature at the bottom is typically 10 nm or more. Wolkow (rwolkow@ualberta.ca) says that although a narrower tip will be useful in the construction of STM arrays (you can pack more tips into a small area; and a wide array might even permit movies of atomic motions) the spatial resolution won't improve thereby. The real benefit of the sharp tungsten tips, he believes, will be as superb electron emitters. Being so slender, they would emit electrons in a bright, narrow, stable stream. |
busterb Monday Aug 21 09:45 PM
"The real benefit of the sharp tungsten tips, he believes, will be as superb electron emitters. Being so slender, they would emit electrons in a bright, narrow, stable stream."
Know nothing about atoms, but any TIG welder will tell ya the Tungsten needs to be sharp. Most times they use a grinder. In the field I've seen a few sharp hands use a torch and blow a nice tip. FWIW
richlevy Monday Aug 21 11:56 PM
Can you imagine bundling a million of them into a shotgun shell and firing them at a target? As flechettes would they obliterate the target or leave it looking unscathed?
Griff Tuesday Aug 22 07:48 AM
I was thinking how easily you could run a spit (skewer) through a...
onetrack Tuesday Aug 22 10:32 AM
So .. if someone says to you .. "you're about as sharp as a tungsten needle under a microscope! .. " .... would that be the ultimate put-down of the 21st century?? 
The 42 Tuesday Aug 22 04:29 PM
No, that would be "You're as big as a tungsten needle!..." 
footfootfoot Friday Aug 25 10:15 PM
I've seen the needle and the damage done
was rather minor
footfootfoot Friday Aug 25 10:15 PM
I'm waiting for a nitrogen sharpening stone to be able to put a molecular edge on my tools.
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