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New High-Speed Nano Imaging Device
Roland Piquepaille writes "Researchers at the Georgia Institute of Technology have built a new nano imaging device which is 100 times faster than current technology. Not only is the 'FIRAT' (Force sensing Integrated Readout and Active Tip) much faster than the current 'AFM' (atomic force microscopy), it also is able to take movies and to simultaneously capture several physical properties of nanostructures, such as stiffness, elasticity or viscosity. In fact, the FIRAT probe, which works like a microphone, could one day replace AFM. One of the researchers commented that 'We've multiplied each of the old capabilities by at least 10, and it has lots of new applications.'"
The major innovation you get by using sound is that your detector can be smaller (i.e. faster) and less reliant on precise optics. This is the double whammy Grail of nano-imaging. From TFA: "For a regular AFM to detect the features of the object, the actuator must be large enough to move the cantilever up and down. The inertia of this large actuator limits the scanning speed of the current AFM. But FIRAT solves this problem by combining the actuator and the probe..." But there seems to be some discrepancy in the article. "Georgia Tech researchers have been able to use FIRAT with a commercial AFM system to produce clear scans of nanoscale features at speeds as high as 60 Hertz (or 60 lines per second)." Is this what they mean by a "movie" which they claim has never been done with AFMs? It's true that commercial AFMs do not achieve this speed, but http://hansmalab.physics.ucsb.edu/index.html/ for example custom builds AFMs to that spec since 2002. The second part that seems misinformed is that FIRAT is not unique in it's use of surface properties and a cantilever-type system. Current AFMs "bounce" off the surface in the same way, interacting well before actual contact (insofar as contact has meaning in the quantum mechanical sense).
I don't see why this is so much different to classical AFM's. First of all, it still is an AFM, only the force detection method is different. Secondly, not all AFM's use cantilevers and optics. There are in fact quite a few alternatives (e.g. tuning forks, piezo resistive cantilevers). And still, even with classical cantilever and optics systems you can achieve much more than 60 lines per second (I first thought it supposed to be 60 frames per second). I worked with such a classical system, and it could scan at a rate of about 300 lines per second. This system was not specifically designed for high speed and was already considered outdated at that time (that was 1999). It is true, that commercial systems are generally much slower than that. But it would surprise me, if one could not find a commercial system which can do 60 lines per second these days. $.
Video-rate AFMs have existed for quite some time. Several exist as commercial products, e.g. http://www.infinitesima.com/VideoAFM/index.html VideoAFM from Infinitesima.
For those with access, anyway. Recent peer-reviewed papers from the group mentioned in the press release Onaran et al, Degertekin et al
First "Drug Screening" most likely be for purposes other than detecting illegal drug usage. It's more likely to be used to detect the effects of various new drugs on various tissue samples.
Many narcotics are highly potent and lethal in small amount
Like caffeine? The LD-50 is only 10 grams.
We can't even control drunk driving, what makes you think that "public" is going to be responsible enough to use marijuana
Because Marijuana is a different drug than alchohol, with much milder effects?
without screaming civil right violation?
Yes, the drug war has resulted in many violations of people's rights.
Alcohol itself is a drug and stupid, making that as some kind of holy grail example to legalize narcotics is nothing but sad and idiotic.
Nah, it shows that legalization, regulation. and taxation works. Heck, it shows that the banning of drugs lead to the formation and prominence of criminal gangs. Alchohol prohibition created the Mob, which lost much of it's power when alchohol was legalized. It also showed that when banned, people tended to drink heavier liquers that were easier to smuggle than safer(relativly) beer and wine. For that matter, drinking went up during prohibition, and went down when it ended.
And I'm sure many cancer patients and HIV infected people are going to cry foul and I do sympathize by supporting State Law to legalize it as prescription medicine
The states can't do much but bluster until the Federal Government moves it out of Schedule 1(no medical use). They say that the medical version is Marinol, but studies have shown it to be both about a thousand times more expensive per dose and not as effective.
Unless you are a Native Indian, please don't even use the word "We" as in "We have been using it as recreational purpose for centries."
How about almost four centuries? Columbus came over in 1492. Marijuana was banned in 1937. That's 445 years. I'll give it over 40 years to spread.
I don't read AC A human right
I work with an AFM, and it's a very tempermental machine. The tips are SO delicate, if you look at them wrong, they break and are useless ($10 down the drain). They can only be used once.
It's a slow process finding the resonance frequency, using the slow piezos to move the tip to the near field, and slowly scanning the area. One of the advantages of AFM is that it can be done on completely wet samples.
There's another technology called NSOM. that does much the same thing. Many NSOMs are custom made. We use a Scanning Electron Microscope to check the tips we make to see if they are suitable. Tips are made by slowly stretching a glass wire inder high temperature until the break, giving you 2 NSOM tips.
Neat stuff.
This is what happens when we continue to trust press releases over actual science.
This may be a great new technique, but there are so many problems with that little blurb, it's amazing. I'm sitting at an AFM right now doing a lot of what they say I shouldn't be able to. Incorporating the Z-actuator on the tip is nothing new, and people are already selling high speed AFMs, and have been for quite some time now.
The cool part is that current systems rely on a one dimensional oscillator to sense forces, while this relies on a two dimensional oscillator, and that seems to be better. The bad part is that it seems to require touching the surface (which is a big problem if you want to incorporate electric forces into your measurement).