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Fall 2008 Seminar Schedule September 11 Nanoscience: when small is big - Gary DeBoer , LeTourneau University 25 Liquid crystals: when rocks are as hard as water Michael Korn and students, LeTourneau University October
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Fall 2008 Seminar Schedule • September • 11 Nanoscience: when small is big • - Gary DeBoer, LeTourneau University • 25 Liquid crystals: when rocks are as hard as water • Michael Korn and students, LeTourneau University • October • 2 Three Major Challenges in Cosmology and Particle Physics, and Their Possible Solutions in String/M-Theory • - Anzhong Wang, Baylor University, Department of Physics • 16 Beauty and the Clot: A Paradigm for Elegance in Design • - Pierre Neuenschwander, University of Texas Health Center, Tyler, TX • 30 LEGS • - Karen Rispin and students, LeTourneau University, Department of Biology • November • 6 TBA • - T. Howard Stone, J.D. LL.M, University of Texas Health Center, Tyler, TX • 13 Of Mice and Matricins • - Andrew Baggett, LeTourneau University, Department of Chemistry and Physics • 20 Ever Consider Graduate School? (6:00 - 7:00 pm) • - Caroline Gattic, graduate school representative • December • 4 History of the elements • -Jim Marshall, University of North Texas • Opinions expressed by the speakers are their own and should not be identified with an official position of LeTourneau University.
Nanotechnology BIG when small is Presented by: Gary DeBoer September 11, 2008 Glaske C101 11:00 am
Some definitions • Quantum wells, 1 D < 100 nm, • surfaces, semi conductors • Quantum wires, 2 D < 100 nm, • carbon nanotubes • Quantum dots, 3 D < 100 nm, • bucky balls • Nanocrystals
I like to point out that this Armchair Quantum Wire endeavor is a "Faith-Based Research Project". It is based on the faith that when God made the universe he wired into the laws of physics and chemistry a path to make this Armchair Quantum Wire, and to do it with great cleanliness and efficiency. If so, then all I have to do is go find that path that God put there in the beginning. With the vast knowledge we have assembled over the years of physics and chemistry, and the sensational new instruments that are now available, we ought to be able to find that path pretty quickly. My short two years at Hope starting as a freshman in 1961 were immensely important to me. I went to chapel, studied religion, and attended church more than I had ever done before, and was with people who took to these issues seriously. I valued that greatly back then. Recently I have gone back to church regularly with a new focus to understand as best I can what it is that makes Christianity so vital and powerful in the lives of billions of people today, even though almost 2000 years have passed since the death and resurrection of Christ. Although I suspect I will never fully understand, I now think the answer is very simple: it's true. God did create the universe about 13.7 billion years ago, and of necessity has involved Himself with His creation ever since. The purpose of this universe is something that only God knows for sure, but it is increasingly clear to modern science that the universe was exquisitely fine-tuned to enable human life. We are somehow critically involved in His purpose. Our job is to sense that purpose as best we can, love one another, and help Him get that job done. http://www.hope.edu/pr/pressreleases/content/view/full/7309 Nanotechnology, when small is the BIG thing Quantum mechanical properties of nano dimensioned things Rick Smalley
Household The most prominent application of nanotechnology in the household is self-cleaning or “easy-to-clean” surfaces on ceramics or glasses. Nanoceramic particles have improved the smoothness and heat resistance of common household equipment such as the flat iron. Optics The first sunglasses using protective and antireflective ultrathin polymer coatings are on the market. For optics, nanotechnology also offers scratch resistant surface coatings based on nanocomposites. Nano-optics could allow for an increase in precision of pupil repair and other types of laser eye surgery. Textiles The use of engineered nanofibers already makes clothes water- and stain-repellent or wrinkle-free. Textiles with a nanotechnological finish can be washed less frequently and at lower temperatures. Nanotechnology has been used to integrate tiny carbon particles membrane and guarantee full-surface protection from electrostatic charges for the wearer. Many other applications have been developed by research institutions such as the Textiles Nanotechnology Laboratory at Cornell University Cosmetics One field of application is in sunscreens. The traditional chemical UV protection approach suffers from its poor long-term stability. A sunscreen based on mineral nanoparticles such as titanium dioxide offer several advantages. Titanium oxide nanoparticles have a comparable UV protection property as the bulk material, but lose the cosmetically undesirable whitening as the particle size is decreased. http://www.nanotech-now.com/current-uses.htm
A plastic nanocomposite is being used for "step assists" in the GM Safari and Astro Vans. It is scratch-resistant, light-weight, and rust-proof, and generates improvements in strength and reductions in weight, which lead to fuel savings and increased longevity. And in 2001, Toyota started using nanocomposites in a bumper that makes it 60% lighter and twice as resistant to denting and scratching. http://www.nanotech-now.com/current-uses.htm
Wilson Double Core tennis balls have a nanocomposite coating that keeps it bouncing twice as long as an old-style ball. Made by InMat LLC, this nanocomposite is a mix of butyl rubber, intermingled with nanoclay particles, giving the ball substantially longer shelf life. Thus far, the only company among the big boys to convert research into tangible products is Wilson, which offers three drivers, a fairway wood, four balls and even a golf bag made using nano-materials. http://www.nanotech-now.com/current-uses.htm
Microfuel cell cell phones using nanotech in the membrane of the fuel cell for better fuel cell performance
The new Chevy Volt, using nanophosphate electrode technologies for faster recharge with lithium ion batteries.
SERS Nanowire Antenna ArraysO.J. Glembocki, Code 6880, Naval Research Laboratory Highly directional Raman Scattering • MAIN ACHIEVEMENT: • Use theoretical EM simulations to determine the best configuration of nanowires geometries and array parameters to produce coherent SERS. • Develop nanowire fabrication techniques that will enable coherent SERS. • Determine the limitations of coherent SERS in relation to directionality • HOW IT WORKS: • ASSUMPTIONS AND LIMITATIONS: • Limitations are that the SERS antenna arrays will be limited to very specific wavelengths. • We can achieve design parameters that will extend from UV to IR wavelengths • Assumption that reproducible nanowires arrays can be fabricated with appropriate geometries and metal coverages. laser STATUS QUO QUANTITATIVE IMPACT laser Raman or fluorescence fingerprint The status quo: Surface enhanced Raman scattering • incoherent process • light scatters in all directions Raman finger print A vehicle for inducing coherency and directionality in SERS and fluorescence. • Theory predicts that closely spaced parallel nanowires exhibit highly directional plasmonic coupling. Arrayed nanowires will produce coherency and high directionality. • Nanowire arrays, with precise spacing control, defined by e-beam lithography and grown by VLS vapor growth will be produced to maximize the effect of plasmonic coupling and light channeling to produce coherent SERS. Nanowire hot spots Coherent SERS Nanowire based antenna arrays that combine plasmonics and photonics NEW INSIGHTS END-OF-PHASE GOAL • Phased arrays result in coherent and highly directional radiation … • Coupled nanowires have highly directional SERS hot spots reducing 4 p scattering. • Arrayed nanowires can act just like phased array antennas. Nanowires arrays that induce coherency and directionality in light scattering processes such as SERS and fluorescence Understanding of SERS based arrays will advance future capabilities in standoff sensor technologies.
SEM 100nm InAs NWs semiconductor atoms from vapor HRTEM nanowire metal-droplet catalyst 20nm S. Prokes (NRL) Au tip R~4nm R. Bass (NRL) VLS Growth • Semiconductor atoms supplied by vapor • Metal droplet (patterned dots) act as catalyst • forms liquid-eutectic with semiconductor atoms • Super-saturation is reached atoms ppt out NW growth begins
Diameter of the nanowire is related to the size of the gold catalyst put down on the silicon. Larger particles of gold begin to behave like films of gold.
Perpendicular nanowires can be grown in arrays Need to coat the wires with Au, Ag, or Ni
Shady Sharka Brilliant Harvard graduate Dog lover No patience for fools
Lovely Lena Postdoc Originally from Russia
Mama Mahdu George Mason graduate student Originally from India
Chucky Charles Faculty Fellow from Howard University Originally from Trinidad
Dashing and Daring DeBoer LeTourneau University Professor Originally from Iowa
Nanotechnology, when small is the BIG thing Manipulation at the nanolevel Drexler Quantum mechanical properties of nano dimensioned things Rick Smalley
Nano = 10-9 Rick Smalley won Noble prize in 1985 Nanotechnology takes advantage of quantum mechanical phenomena The NRL is in Washington DC Mama Mahdu disappeared Lovely Lena was a KGB-CIA intelligence agent Shady Sharka was misappropriating federal funds Nanobots could turn the world to gray goo? LeTourneau has a nanoscience/technology class? TRUE FALSE