Technology bulletin 594

Explosive-detection portal begins airport tests

Some airline passengers who visited the main security checkpoint at the Albuquerque International Airport recently tried out tomorrow's technology for combating terrorism. The "explosives-detection portal" is under development at Sandia National Laboratories for the Federal Aviation Administration. The detector relies on chemical preconcentrator technology developed by Sandia to protect critical nuclear weapons facilities. It identifies passengers and employees who have recently worked with any of a wide range of explosive chemicals. Although specific information about the portal's capabilities (the types and quantities of explosives it can detect) cannot be disclosed for security reasons, the system can detect very small concentrations of all "explosives of interest" says Kevin Linker, Sandia's lead researcher for the project. Passengers stand inside the portal for a few seconds as the detector passes a quiet, gentle "puff" of air over them. The air sample is collected and passed through a chemical sensor, which recognizes the chemical "signatures" of a variety of explosives. E-mail [email protected].

New microchip could mean improved cars, knees, or mice

A specialized microchip developed at Simon Fraser University (Burnaby, BC, Canada) could improve the way airbags deploy in crashes, calculate the punishment runners inflict on their knees, or even build a better computer mouse. The SFU work, dubbed "Project Hot Air," employs a hot air bubble at the heart of the microchip. Prototype chips have proved to be 1,000 times more sensitive than current devices, according to Albert Leung, SFU's school of engineering director. The researchers have applied for a worldwide patent before publishing their research results. "We hope the technology will be transferred to private industry," Leung adds, "where sufficient research and development budgets can take advantage of the full commercial potential." E-mail [email protected].

Brazed copper-brass radiators head to production line

Universal Auto Radiator Manufacturing Co. (UAR) will begin using the new CuproBraze(R) manufacturing process, developed by the International Copper Association (ICA), to make the first commercially available brazed copper-brass radiators for cars and trucks. "This new technology will make copper-brass radiators the preferred choice of automotive manufacturers worldwide," says Johan Scheel, vice president of ICA. "Besides shortening manufacturing times and lowering manufacturing costs, the process produces a superior product." Scheel adds that the CuproBraze process "offers significant advantages over the Nocolok process used for aluminum radiators, including less energy usage, lower scrap rates, wider temperature margin in the brazing furnace, and substantially greater through-put rates." The no-flux, brazed radiators are said to be 30-40% lower in weight than traditional copper-brass models, can be made smaller than their aluminum counterparts, and can provide 30% lower air-side pressure drop. FAX (212) 251-7245.

Low-temperature catalyst on trial for boiler systems

Pennsylvania State University researchers have tested a low-temperature, nitrogen-oxide reduction catalyst for potential use in small-production boiler systems. "Babcock & Wilcox has a high-temperature process that combines sulfur dioxide, nitrogen oxide, and particulate emission control for coal-fired boilers they call the SOx NOx Rox Box," explains Andre L. Boehman, Penn State assistant professor of fuel science. "We are trying to modify this process to permit combined emissions control at the much lower temperature common in industrial-scale boilers." Under test is a commercially available catalyst supplied by Engelhard Corp. that might eliminate the need for flue gas reheating and expensive high-temperature baghouse bags. A first round of pilot-scale tests used a combustor fired by natural gas; a second round of tests will use a fuel containing sulfur. The researchers have achieved NOx conversion at 95%, but with 50% of the conversion product nitrogen and 45% nitrous oxides. "This system works between 350 to 400F, which is in the range of the baghouse temperature in our demonstration boiler," Boehman adds. E-mail [email protected].

Virtual walls tune older concert halls

A feature that characterizes the acoustic environment required by different types of music focuses on reverberation time. Expressed in seconds, this corresponds to the time taken for sound to diminish by 60 decibels in an auditorium. For instance, a low reverberation time is best for theaters and conference halls, while a relatively higher time rich in low frequencies proves better for symphony-music quality. That's why acoustic engineers at France's Centre Scientifique et Technique du Batiment (CSTB) designed an electro-acoustic system that can modulate the acoustics of an auditorium based on its use. Baptized CARMEN, for Active Control of Reverberation by a Natural Effect Virtual Wall, the system obtains a natural reverberation effect--without modifying the architecture of a building or using microphones on stage. The system consists of 16 to 32 active cells, each containing a microphone, an electronic filtering unit, a power amplifier, and a loudspeaker. Distributed around the walls and ceiling, the cells form virtual walls that are controlled by a computer. FAX Mireille Heros at +(33) 1 40 50 28 56.

Polymeric membranes stretch gas separation applications

A new type of polymeric gas separation membrane able to operate at elevated temperature and withstand harsh chemical environments could help expand the use of industrial separation processes. It also could allow the recovery of large volumes of hydrogen gas now discarded in petrochemical processing, reducing the environmental impact of refining processes. Researchers at the Georgia Institute of Technology produced the new membranes by blending a non-reactive polyimide with a new diacetylene-functionalized polyimide. The blend was dissolved in methylene chloride and formed into a film using conventional techniques. Finally, it was heated to initiate a crosslinking reaction in the diacetylene-containing portion of the polyimide blend. "We believe these new materials retain their gas transport properties because the crosslinkable groups can undergo a solid-state reaction without significantly increasing the density of the material," explains Haskell W. Beckham, an assistant professor in Georgia Tech's School of Textile and Fiber Engineering. E-mail [email protected].

Center for electronics manufacturing formed

The Electric Power Research Institute (EPRI) and SEMATECH have established the EPRI Center of Electronics Manufacturing (CEM). To be based at SEMATECH in Austin, TX, the center will address productivity, environmental, and energy issues in the electronic industry, particularly semiconductor manufacturing. "CEM will open the door to collaboration with the electricity industry to pursue mutually beneficial technical initiatives," reports Frank Squires, senior vice president and chief administrative officer at SEMATECH. "It will not only advance the goals of the National Technology Roadmap for Semiconductors,but provide semiconductor manufacturers with access to innovative technologies developed by EPRI." E-Mail [email protected], [email protected].

Age of complex, 'self-organizing' polymers ushered in

Today, synthetic structures are designed with only one structure-forming process in mind. With complex, self-organizing polymers, molecular-scaled, multilayered devices can be built with each layer designed for a different function, says Christopher K. Ober, associate professor of materials science and engineering at Cornell University's College of Engineering. Ober feels that such self-organizing materials, which include liquid crystal polymers, block copolymers, hydrogen-bonded complexes, and many natural polymers, could hold the key to developing new structures and devices in many advanced technological industries. For example, through spontaneously grown cylinders within a polymer structure, technology could produce wires as small as 100 angstroms in diameter. Cornell University researchers have carried out such explorations through funding provided by the Office of Naval Research Laboratory, the Air Force Office of Sponsored Research, and the National Science Foundation. E-mail [email protected].

Association to explore Internet tools and protocols

The diffuse structure of the Internet is one of its strengths. However, this same competitive environment has made collaboration on operational and engineering improvements difficult. Moreover, the collection of accurate measurements of Internet traffic, routing patterns, and throughput has become virtually impossible. To help address these concerns, the National Science Foundation (NSF) has awarded a seed grant of more than $3 million over three years to the University of California, San Diego. The funds will help establish the Association for Internet Data Analysis (CAIDA). The association's aim: to promote a more robust, scalable Internet infrastructure. Such action, says Tracie Monk, CAIDA director of external affairs, will foster engineering and technical partnerships among Internet vendors and user groups. One result of CAIDA already in beta release for testing is a Mapnet. This Java-based visualization tool to enable researchers to see a representation of the topology and bandwidth of networks that make up the global Internet. E-mail [email protected].

First production model advanced MD Explorer takes flight

The advanced MD Explorer twin-turbine, eight-place helicopter made its maiden flight recently at a Boeing facility in Mesa, AZ. "The new MD Explorer is undoubtedly the best commercial helicopter we've ever built," enthuses Erv Hunter, vice president of Boeing's Light Helicopter Program. The new helicopter incorporates advances in technology, more powerful engines, and improvements in the aircraft's basic design that should result in improved performance and lower direct operating costs, including an 8% increase in range and 4% more endurance. Among the physical changes in the aircraft: improved engine air inlets, new Pratt and Whitney 206E turbine engines, increased thermodynamic ratings, improved NOTAR (a system for anti-torque and directional control that replaces the traditional tail rotor) inlet design, and an improved stabilizer control system. To give the aircraft greater flexibility in its operation, particularly in Europe and other areas with stringent operating requirements, the helicopter will be certified for "Category A" performance. FAX (602) 891-5599.