Technology Bulletin

My Bonnie lies over the ocean, but fiber may bring her back

With the speed and number of wavelengths that a new undersea fiber can provide, network providers will be able to bring back more than just Bonnie. TrueWave^® Submarine Reduced Slope (RS) from Lucent Technologies (Atlanta, GA) offers a reduced dispersion slope which enables network providers to increase the number of channels and transmission speeds of their networks, while providing a future-proof solution for emerging transmission technologies such as dense wavelength division multiplexing. According to Lucent, service providers can deliver higher bandwidth to customers because the TrueWave fiber supports up to 10 gigabits per second over 21 wavelengths in a single fiber. By comparison, trans-oceanic networks installed as little as a year ago operated at 5 gigabits per second over 8 channels. E-mail: mcabee@lucent.com.   

Say Cheese! A sensor that takes pictures in clouds, rain, or fog

A fine resolution, real-time synthetic-aperture radar (SAR) system, developed by the Department of Energy's Sandia National Laboratory (Albuquerque, NM) and General Atomics (San Diego), takes photograph-like images in rain or fog, through clouds, and in day or night conditions. Lynx, the 115-pound all-weather sensor, can be mounted on both manned aircraft and unmanned aerial vehicles and operate at a range of 85 km. Flying at an altitude of 25,000 ft, the Lynx SAR produces one-foot resolution imagery at standoff distances of up to 55 km. At a resolution of four inches, the radar can make images of scenes 25 km away. The radar forms an image that is larger than that displayed, storing it in cache memory. This allows the operator to pan around within the total scene in order to concentrate on a particular area of interest. The sensor can detect small surface penetrations such as footprints in a soft terrain. The device picks up the slightest change in a scene using a technique called coherent change detection. Not only can the Lynx detect moving targets, but future versions will be able to image seaborne targets, cue other sensors, and take 3D images. E-mail: whhensl@sandia.gov.   

Polymer coating combines flexibility with environmental properties

A new coating material that emits virtually no volatile organic compounds (VOCs) during application could replace conventional solvent-based paints and anti-corrosion coatings in a wide range of uses. Based on a durable polyester material, the coating can be tailored to provide the specific properties required by different applications. Developed by a research team at the Georgia Institute of Technology, the patented ultra-low VOC coating would meet new environment regulations expected to severely limit VOC emission from paints and other coatings. Conventional polyester coatings are cross-linked and cured in a process that involves removing a small volatile molecule and evaporating an organic solvent. The small molecule and solvent usually evaporate into the atmosphere, becoming pollutants. But the Georgia Tech process removes and captures that small molecule during the manufacturing process and does not require a solvent. In the process, cyclic polyester oligomer molecules are polymerized using an organo-tin or organo-titanate catalyst to form a material that can be either a powder or liquid at room temperature. Once applied to a surface, the coating is cured using heat or ultraviolet light to rearrange the cyclic polymer to a linear and cross-link structure. "The fundamental science, the construction of the cyclic oligomers, their physical and chemical properties, and the polymers that are produced on surfaces are all fairly well characterized," says Charles Liotta, professor in the School of Chemistry and Biochemistry. "But for this to be commercially viable, we need to produce thousands of tons per year. We are still exploring how to do that." E-mail Charles Eckert at cae@che.gatech.edu. 

Powder metal parts perfected in a microwave oven

Anyone who uses a microwave knows that, generally, metals, such as aluminum foil, should not be placed in these ovens. However, a team of Pennsylvania State University material scientists is microwaving a wide range of powder metals--and producing machine components with improved properties. "Solid metal causes problems in microwaves because they reflect, rather than absorb, the microwave radiation," explains Dinesh K. Agrawal, director of Penn State's Microwave Processing and Engineering Center. "Powder metals do absorb microwave radiation and can be heated and sintered using microwaves." A solid, dense material forms after the microwave treatment. The key to microwave sintering of the powder metals is the specialized, insulated sintering chambers. In conventional thermal sintering, the sintering oven is heated and this heat is transferred to the greenware. But microwaving does not heat the chamber, just the greenware. Without insulation, the heat generated in the greenware would be lost to the inside of the microwave cavity and take an enormous span of time to reach the required temperatures. "Our findings indicate that virtually any powder-metal green body can be sintered in 10 to 30 minutes in an appropriate microwave sintering apparatus," the researchers report. Commercialization of continuous-processing equipment for microwave sintering is currently underway. E-mail: dxa4@psu.edu.   

Technology takes gas-assist molding to higher level

Ferromatick Milacron (Cincinnati, OH) has developed a comprehensive patented technology that it claims takes gas-assisted injection molding to higher levels of capability and quality. Milacron received U.S. patents on both the apparatus and the process for applying the gas assist, according to Bruce Kozak, managing director, Integrated Processing Systems. The process, called Airpress III, delivers high repeatability with uniform quality to overcome common gas-assist defects, such as surface finish marred by flow or sink marks and wall thinning or breakthrough, Kozak explains. It achieves uniform quality by fully filling the cavity with plasticized material, waiting for the melt to cool against mold walls, then strategically applying gas assist to force out some of the plasticized material and create internal cavities. More traditional approaches to gas assist inject only enough plasticized material to achieve the final shape, then use gas-injection to force the melt against the mold wall. Fluid dynamics under these conditions often cause undesirable flow marks or wall thinning. Visit Ferromatik-Milacron's home page at www.ferromatik.com for more details.

Interactive DVD players to debut

Ever want to see the movie script and storyboard of High Noon? Or maybe the in-depth cast biography? Even if you didn't, you may soon be able to view scripts and incidental tidbits on your favorite stars via your television. NUON, VM Labs' next generation DVD technology transforms DVD players into multimedia centers that support interactive content, enhanced DVD movies, games, and other applications. With its embedded high-speed media processor, associated firmware and operating system, NUON provides a platform to bring dynamic interactive features to your living room. Along with a browser such as Spyglass Device Mosaic, DVD users can view interactive content written in HTML that is designed by Hollywood's entertainment systems to complement digital movies. Toshiba will include NUON in future digital consumer products. E-mail: eleborgne@spyglass.com. 

Butterfly wings and optics

The beautiful color that we enjoy in butterfly and moth wings is not always produced by pigmentation. Instead, their striking appearance comes from interference effects from micro-structures located on their wing scales. These structures have inspired the work of Johan Brink in South Africa where he and his colleagues are studying various types of insects indigenous to the continent in the hopes of developing new devices for solar cells, telecommunications, and data storage. A mango moth has wings covered with a stack of layered thin films similar to the anti-reflect- ion coating on camera lenses. The color changes from green to yellow to orange and purple by simply varying the spacing of the layers and the angle of view. By changing the surface design, a highly reflective surface becomes non-reflective. This could have applications as light collectors for solar cells. E-mail: biojab@vopi.agric.za. 

Parks go wild for metalizing

Companies that want to achieve the look of metal, without the expense and inconvenience of relying on a forged metal process, have a new choice--LuminOre. Recently patented, the cold-spray, cold-cast or hand-applied process uses standard spray equipment and metal polishing tools. The resulting composites contain up to 95% metal, provide a seamless application, conduct heat, and are validated not to conduct electricity, according to LuminOre's Tom Valente Jr. Players in the motion-picture and theme-park industries are already using the composite metals for film sets and props, Valente reports. He adds that the material also can provide computer and computer-component manufacturers with an electrical insulation capability "equal to that of ceramics, but with two or three times the heat diffusion." Visit www.LuminOre.com. 

Moleculars "motor" between cells

Coupling the organic and inorganic, biological engineers at Cornell University (Ithaca, NY) demonstrated the feasibility of small, self-propelled bionic motors that do their builders' bidding in plant, animal, or human cells. Such machines could travel through the body, functioning as mobile pharmacies dispensing precise doses of chemotherapy drugs exclusively to cancer cells, for example. The device, the result of integrating a living molecular motor with a fabricated device at the "nano" scale, is a few billionths of a meter in size. The first integrated motor, a molecule of the enzyme ATPase coupled to a metallic substrate with a genetically engineered "handle," ran for 40 minutes at three to four revolutions per second, Carlo Montemagno and George Bachand report in the September issue of the journal Nanotechnology. The "handle" for attaching the ATPase motor to the nanofabricated metallic substrates is a synthetic peptide composed of histidine and other amino acids. The histidine peptide allows the molecular motors to adhere to gold, copper or nickel--the three standard contact materials in integrated circuits. The patterned metal substrates were created by evaporative deposition at the Cornell Nanofabrication Facility. Although the device will have more brawn than brains until the molecular motors are attached to more advanced devices that can provide instructions, Montemagno says this is a significant step toward the seamless integration of nanoscale technologies into living systems. E-mail: hrs2@cornell.edu.