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How The Nano “Revolution†Happened. 0.000000001. Kasetsart University November, 2004. But first, what is nano?. 1 nm = 1 × 10 -9 m 500 nm  Visible Light ( blue-green ) 1 Å = 1 × 10 -10 m  typical chemical bond (1.5 Å) 1 Å = 0.1 nm. 1.09 Å. 0.154 nm. C. 1.54 Å. H. C. H. C.
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How The Nano “Revolution” Happened 0.000000001 Kasetsart University November, 2004
But first, what is nano? 1 nm = 1 × 10-9 m 500 nm Visible Light (blue-green) 1 Å = 1 × 10-10 m typical chemical bond (1.5 Å) 1 Å = 0.1 nm 1.09 Å 0.154 nm C 1.54 Å H C H C C 0.109 nm
Does the Language of Units Matter? Body temperature 100oF 37oC = “hot” 1 foot = about the size of your foot! No such simple, physiological reference for the meter (about the length of your leg?) 1000 mL = a lot easier for chemists to imagine than 1 dm3 1 atm = a lot easier to imagine than 101,325 Pa The discipline of Chemistry often loses the battle of language. The nano revolution is yet another such case, because the natural “unit” of Chemistry is the Angstrom.
More Syllables Angstrom = 2 syllables Nanometer = 4 syllables So….old people, who have learned that no one listens anyway, prefer Angstrom to Nanometers.
Example: CdSeZnS quantum dots Absorption & emission of 5 different sizes Dispersed in toluene. These particles have many advantages over conventional fluorophores—not easily bleached, broad excitation spectrum, narrow & tunable emission, long fluorescence lifetimes. http://smb.chem.ucla.edu/research/nc.htm
Gold particles made by alfalfa, a forage crop http://www-ssrl.slac.stanford.edu/research/highlights_archive/alfalfa.html Gardea-Torresdey UTEP
Richard P. Feynman http://www.feynmanonline.com/ The Feynman Lectures on Physics • “There is plenty of room at the bottom.” • December, 1959, exposition of just how much might • be achieved by focusing on the enormous gap between • the nano world and the big world. • This talk was a social function—an after dinner talk. • Replication of machines, each smaller than parent. • Information on head of pin and in head of pin. Who knows the word “pin”?
1/16”=1.5875 mm = 1,587,500 nm =15,875,000 Å 1/32”=0.79375 mm =793,750 nm =7,937,500 Å Pin head volume: 1.6 × 1018 Å3 Age of universe in seconds: ~3 x 1017
Miniaturization at the dawn of the space age is not as we now imagine. Miniaturization was on everybody’s mind, following Sputnik – small guidance systems, radios, control systems. “That’s nothing. That’s the most primitive, halting step in the direction I intend to discuss.” “Why cannot we write the entire 24 volumes of the Encyclopedia Brittanica on the head of a pin?”
Visual approach: simply shrink the text. This requires the text to be reduced by 25,000 times. Each letter then would then be several tens of atoms large. “…there is no question that there is enough room on the head of a pin to put all of the Encyclopedia Britannica.”
Coded approach: dots and dashes, e.g. let A -Also: the pin has a finite thickness; we can use that, too. Voxel = 3-D pixel 125 atoms All information in all the world’s 24 million books (in 1959) will now fit into the head of a pin.
A billion tiny lathes Feynman raised the idea that a machine could make a replica of itself, only smaller. Then, the smaller machine could make a replica of itself. And so on and so on… Feynman allowed that such machines might one day manipulate just small number of atoms, and he didn’t worry much about thermal vibration—the kT problem.
The Two Feynman Prizes The first was for reducing information on a page by 25,000 times, so it could be read by an electron microscope. “And I want to offer another prize…of (a thousand dollars) to the first guy who makes an operating electric motor – a rotating electric motor which can be controlled from the outside and, not counting the lead-in wires, is only 1/64th inch cube.” 1/64th inch = 0.4 mm = 400 m = 400,000 nm
William McClellan’s award-winning motor…but it broke no new ground. It is just a conventional motor, made very small using galvanometer wire and assembled under a microscope.
K. Eric Drexler, “author, theoretical researcher, and policy advocate focused on emerging technologies and their consequences for the future.” -- The Foresight Institute http://www.foresight.org/FI/Drexler.html
About Drexler • Almost my age. • Spent part of his youth in Denver, my home town. • Obviously, having a career of higher impact! • I do not know how much science he has actually done. He clearly thinks about science a lot. • Maybe compare to Leo Szilard of a previous generation? (Szilard thought about nuclear weapons and their social implications.)
Anyway, the point is… • Drexler was interested in space colonization during his MIT years (1970’s). • Began to think of ways to make machines that manipulate matter – e.g., why not a nanomachine that converts grass to meat to replace this “machine” in the “big world”? • In the 1970’s the best manipulators of molecules were the biotech people, so why not imagine proteins—maybe synthetic—that would follow codes—maybe like DNA—to do what we want? • Drexler’s ideas were independent of Feynman, whose 1959 banquet speech was, by that time, largely forgotten.
Proc. Natl. Acad. Sci. USA Vol. 78, No. 9, pp. 5275-5278, September 1981Chemistry section Molecular engineering: An approach to the development of general capabilities for molecular manipulation KEY WORDS: molecular machinery/protein design/synthetic chemistry/computation/tissue characterization K. Eric Drexler Space Systems Laboratory, Massachusetts Institute of Technology,Cambridge, Massachusetts 02139Communicated by Arthur Kantrowitz, June 4, 1981 ABSTRACT: Development of the ability to design protein molecules will open a path to the fabrication of devices to complex atomic specifications, thus sidestepping obstacles facing conventional microtechnology . This path will involve construction of molecular machinery able to position reactive groups to atomic precision. It could lead to great advances in computational devices and in the ability to manipulate biological materials. The existence of this path has implications for the present. “it seems difficult to maintain that nonprotein machine components cannot be built and assembled”
What did Feynman think of Drexler? “That’s simple stuff. It’s obvious. Why doesn’t he work on something difficult?” *according to author Ed Regis, Feynman was a guest at a Drexler party, and was asked what he thought by another guest, who was unaware that he was that Richard Feynman.
US Government Studies 1995 It is unclear which fabrication method will best succeed… Areas that are important…include: • Macromolecular design and folding • Self-assembly methods • Catalysis • Dendrimers, fullerenes and other novel structures • Bioenergetics, nanobatteries, and ultrasound-driven chemistry • Semiconductoro-organic/biological interfaces • Miniaturization and massive parallelization of (surface force microscopy) • Molecular modeling tools
1995 • “Demonstration of assembly, control of chemistry and practical component and integration are important.” • Produce material parts at nanoscale • Process the parts into components • Order the components and interconnect • Control massive collection of miniature parts and systems • Provide power How to coordinate such an effort among NSF, NIH, DARPA, NIST, Industry?
Dangers • Lethal and specific poisons • Potent drugs/new forms of drug abuse • Uncontrollable viruses • Sabotage by miniature robotic attackers • Competition with superior artificial intelligence
2001 Report: A broader technology report, with a more realistic, limited approach with benefits in the short term • Clothes that respond to weather, interface with information systems, monitor health and deliver medicines, protect wounds. • Personal identification & security. • Buildings and cars that adjust to weather. • Integration of chemical, fluidic, optical and mechanical systems with biological functions and computer logic. • Artificial tissue growth for heart, blood vessels. • Functional materials—e.g., polypeptides.
2001 – broader impacts • Accelerating pace of technology—lifelong learning. • Increasing interdisciplinarity. • Competition—e.g., with EU (in 1995, the concern seemed to be Japan). • Reduced privacy. • Too much knowledge: if nanosensors of brain function teach us how we form false memories, will we have to know the mental state of a witness in a murder trial? • Nanorobots--”…it seems unlikely that macro-scale objects could be constructed using molecular manufacturing within the 2015 timeframe.”
Nanowires from electrodeless reduction of Ag onto DNA. The wires get thicker with each exposure to the AgNO3 solution.
Top-down, lithography, epitaxy, etc. Bottom-up, chemical assembly We’re a long way from self-replicating, reducing machines.
Should it win a Feynman Prize ? IBM spelled out using 35 atoms of Xe
Nanotechnology viewpoints • Nanoscience may viewed in many ways. • Some people think it is all hype! • Some people think it distracts from the fundamental studies that got us this far. • Some people don’t care—just want a job!
I am still not sure! My provisional viewpoint • Some of Nano is definitely hype. • So what? Take the money and have fun! • Science has always oscillated between opportunistic exploration and fundamental studies. That the pendulum has swung towards exploration and away from basics science is no cause for alarm. • Students should still learn fundamentals so they can be ready for the next trend (and not make idiots of themselves during this trend cycle). • The emergence of Nano probably is a symptom of the aging of Chemistry—or maybe Chemistry remaking itself.
Chemistry as we know it Needs periodic table!
ATGC TACG Many new Nano alphabets? • Dendrimer generations • Fullerenes: C60, C70, etc. • Even silica particles of different sizes??? • Various nano-rods • DNA parts with complementary “glue”
We Hobbits can ride the great shoulders of the ents. While it is helpful to know as much as possible of the past, perhaps the immediate future belongs to visionaries who know how to put together capabilities. This is a new approach. It seems to underlie much of nanotechnology—application of old facts, with rather less attention paid to fundamentals. Treebeard http://fan.theonering.net/middleearthtours/ents.html
Ruska, Binnig, Rohrer Origins Onsager Svedberg We can thank colloid chemists and polymer chemists, like these Nobel prize winners, for establishing some of the language and methods for studying material on the nanometer scale. Often it has been macromolecular greatness that contributes to nanotech. Rayleigh Flory De Gennes Staudinger Debye Langmuir Merrifield Heeger, Shirakawa, McDiarmid
Confession and Caveat I am a physically-inclined macromolecular scientist, not a nanotechnologist. Already the nano field is very large, so even the most best nano expert would not be able to cover all of it. Let’s just have fun with some of the nano possibilities.
Nano Centers UCLA/UCSB: CNSI http://www.cnsi.ucla.edu/news.html Institute for Nanosoldier Technologies Rice CBM2
References Nano, by E. Regis. Little, Brown & Co. Boston, 1995 (T174.7 R44) Nanocosm, by W.I. Atkinson, Amacom, New York, 2003 (T174.7 A88) The Global Technology Revolution, Bio/Nano/Materials Trends and their Synergies with Information Technology by 2015, prepared for the National Intelligence Council, by P. S. Anton, R. Silberglitt, J. Schneider, Rand Corporation, National Defense Research Institute, Santa Monica, 2001 (T173.8 A58) The Potential of Nanotechnology for Molecular Manufacturing, by M. Nelson, C. Shipbaugh, Rand Corporation, Santa Monica, 1995 (T174.7 N45)