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INNOV Emerg Tech.Qxp INNOVATIONS IN MATERIALS TECHNOLOGY EMERGING TECHNOLOGY Nanoscience computational tools developed for Internet BRIEFS A five-year, $18.25 million grant from the National Carl Zeiss SMT Science Foundation to support the U.S. National announces that Nanotechnology Initiative with expanded capabili- Harvard University’s ties and services for computer simulations on the In- Faculty for Arts and Sciences has selected ternet has been received by the Purdue University eight Zeiss scanning and Network for Computational Nanotechnology, West transmission electron Lafayette, Ind. microscopes, focused- “With the help of our five partner universities, we ion-beam analytical are growing beyond our roots in nanoelectronics to systems, and one of the new areas such as nanofluidics, nanomedicine, world’s first helium ion nanophotonics and applications of nanoscience to the microscopes for its environment, energy, the life sciences, and homeland Center for Nanoscale security,” says network director Mark Lundstrom. Systems. www.zeiss.smt.com The gateway for this global network is the nanoHUB, a free Internet-based science gateway This image of a quantum dot was produced by a simulation via the nanoHUB. This image shows the The Center for used by more than 3000 national and international computed second excited electron state of a quantum Nanoscale Materials researchers and educators every month. In addition dot nanodevice in which electrons resonate and emit at the Department of to online simulation services, the site’s menu includes pure bright light. (Image by Wei Qiao, David Ebert, Energy’s Argonne courses, tutorials, seminars, podcasts, and reviews Makerk Korkusinski, Gerhard Klimeck) National Laboratory of tools and content. is now fully operational. For more information: Gerhard Klimeck, Purdue University, West Lafayette, IN 47907; tel: The recent completion of the hard X-ray nano- 765/494-9212; [email protected]; www.purdue.edu. probe beamline and the installation of a Beowulf- Novel nanomaterials built on large scale by soft lithography class supercomputer An innovative and inexpensive way of making nanomaterials on a large scale has been devel- array with 12 teraflop oped at Northwestern University, Evanston, Ill., and funded by the National Science Founda- capacity will enable tion, Arlington, Va. The technique, known advanced R&D. Tungsten may provide durable as soft interference lithography (SIL), www.anl.gov wall material for fusion tokamak combines bottom-up and top-down ap- NASA researchers have A fusion containment wall completely clad with tungsten would proaches, merging chemistry with ma- designed and built a new provide advantageous thermal properties, low sputtering caused terials fabrication. Simple nanofabrica- circuit chip that can take by hydrogen, and no long-term accumulation of tritium, say tion techniques control the alignment, extreme heat. The silicon researchers at Max Planck Institute of Plasma Physics (IPP) in size, shape, and periodicity of nanopat- carbide chip exceeded Garching, Germany. Only a few hundred thousandths of a percent terns; and chemical methods control ma- 1700 hours of contin- of the tungsten would penetrate to the core of the plasma, with terials properties and crystallinity. SIL of- uous operation at 500°C fers many significant advantages over (930°F), a breakthrough little effect on fusion yield. that represents a 100-fold existing techniques, including the ability Tungsten experiments at IPP included applying tungsten to increase in what has special areas of the wall otherwise completely clad with carbon to scale up the manufacturing process to previously been achieved. tiles. The positive result prompted a further reduction of carbon. produce devices in large quantities. www.nasa.gov The aim was to check how this affected the plasma and its With the new nanomanufacturing tech- interaction with the tungsten components. In order not to nique, Prof. Teri Odom and co-workers jeopardize other research objectives, the tungsten surface was have succeeded in making gold films with only successively enlarged. Once the necessary measuring virtually infinite arrays of perforations methods were developed, it was found that even an extensive as small as 100 nanometers. On a mag- tungsten surface does not unduly affect the plasma. nified scale, these perforated gold films For more information: Isabella Milch, Max-Planck-Institut fuer look like Swiss cheese, except the perfo- rations are well-ordered and can spread Plasmaphysik, Germany; tel.:(0)89 3299-1288; over macroscale distances. The ability [email protected]; www. www.ipp.mpg.de. to make these optical metamaterials ADVANCED MATERIALS & PROCESSES/DECEMBER 2007 15 BRIEFS Rice University and Nan- inexpensively and on large wafers or sheets sets this work apart from other techniques. yang Technological Uni- For more information: Prof. Teri Wang Odom, Northwestern University, Evanston , IL versity announce the forma- 60208; tel: 847/491-7674; [email protected]; www.northwestern.edu; www.nsf.gov. tion of a $2.6 million Institute for Sustainable Nanoelec- tronics, which aims to slash Solid-state photo-electrochemical the design and production costs cells provide higher efficiency for embedded microchips. Solid-state photo-electrochemical cells for converting solar radiation to electricity with www.rice.edu higher efficiency than possible today have been proposed by researchers at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. The proposed cells could be fabricated by layering Semiconductor Research nanocomposites of active particles with organic binders on flexible polymer substrates. Each Corp. has formed a partner- ship with the National Insti- cell would contain a dye-sensitized semiconductor electrode, a proton-conducting solid tute of Standards and electrolyte, and a solid-state proton-intercalation counter electrode. Technology to develop a rad- By designing the cells to rely on protons as the charge carriers, it should be possible to ical yet practical successor to enable the cells to sustain rates of transport and concentrations of charge carriers greater CMOS, the basic electronic than those of state-of-the-art photo-electrochemical cells designed to rely on hole conduc- building block in today’s com- tion and organic semiconductors. The proposed cell configuration is expected to minimize puters, and to demonstrate its the incidence of recombination of holes and electrons, thereby minimizing the associated feasibility in computer circuits energy losses and contributing to greater energy-conversion efficiencies. during the next five to ten years. www.src.org For more information: Sri R. Narayan, NASA Jet Propulsion Laboratory, Pasadena, CA 91109-8099; tel: 818/354-2240; www.jpl.nasa.gov. For more information, download the Technical Thermo Fisher Scientific Support Package at www.techbriefs.com/tsp under the Electronics/ Computers category. Inc. announces the availability of a new online demonstration Steelmaking challenge enables designed to enable current and prospective customers to dis- simulating production online cover the features, benefits, and The Virtual Steelmaking Challenge is an annual competition for students and steel in- mode of operation of Thermo dustry employees, sponsored by the International Iron and Steel Institute, Brussels, Bel- Scientific S Series atomic ab- gium. Steelmaking simulations enable competitors to develop and produce a particular sorption spectrometers. www. grade of steel at the lowest cost. thermo.com/aa The competition challenges entrants to develop and produce a particular grade of steel at the lowest cost. For the 2007 contest, participants will refine and cast ‘virtual steel’ using the The University of Dela- secondary steelmaking and continuous casting simulations. The specific grade to be processed ware has won a competitive is announced just before the Challenge starts. Multiple attempts are allowed during the 24 award of more than $7 million over five years from the hour period. IISI will award two prizes, one for the best industry entry and the other for the National Institute of Stan- best university entry. Other local prizes may also be awarded. dards and Technology, to Go to steeluniversity.org for more information, and to register to participate. www.world- develop the next generation of steel.org; http://www.steeluniversity.org/ neutron scattering instruments through the creation of a Center Magnesium nanoblades grown for Neutron Science. www. udel.edu via angle vapor deposition Magnesium nanoblades that are extremely thin, with very large surface areas, have re- portedly been grown by researchers at Rensselaer Polytechnic Institute, Troy, N.Y. The sharp nanometer-scale surface is quite different from any other nanomaterial that has been grown via oblique angle deposition, according to Prof. Gwo-Ching Wang. To create the nanoblades, the researchers vaporized magnesium, allowing the vaporized atoms to deposit onto a surface at an angle. As the magnesium deposition angle was in- creased, the structures first tilted away from the magnesium vapor source instead of the ex- pected inclination toward the source. The blades then quickly curved upward to form nearly vertical structures resembling nanoscale razorblades. At a 75-degree angle, the nanoblades had a thickness of as little as 15 nanometers and a width of a few hundred nanometers. The nearly two-dimensional structure changes the traditional understanding of oblique angle deposition, which was previously thought to always build cylindrical structures such as nanorods or nanosprings. They also are surprisingly spread out for a uniform nano- material, with one to two micrometers between each blade. The vast surface area of each nanoblade, coupled with the large spaces between each blade, could make them ideal for hydrogen storage. For more information: Gwo-Ching Wang, Rensselaer Polytechnic Institute, Troy, NY 12180; tel: 518/276-8387; [email protected]; www.rpi.edu. 16 ADVANCED MATERIALS & PROCESSES/DECEMBER 2007.
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