The two spectrometers will measure the solar wind during Cassini's voyage to Saturn, which began on Oct. 15, 1997. Once it arrives at the planetary system, it will search for beams of ions within the planet's magnetic field and sample the atmosphere of Titan, Saturn's largest moon. Such data will help scientists back on Earth identify the physical processes taking place on the surfaces of the moons and within Saturn's rings.

The IMS is designed to measure the mass and energy of electrically charged plasmas trapped in Saturn's magnetic field. An ion will enter the unit's cylindrical time-of-flight analysis chamber by passing through a carbon foil only a few dozen atoms thick. This will activate a clock that times the ion's flight through the linear electric field permeating the cylinder. The time needed to transit the cylinder yields a highly accurate measurement of the ion's mass.

The IBS, meanwhile, consists of two nested hemispheres of aluminum, each approximately 8 inches in diameter, which will provide a high-resolution energy spectrum of any beamed plasmas that may be encountered by rapidly varying the electric field between the two hemispheres. Three small openings allow ions to enter at the base of the hemispheres. An electrical voltage forces ions of the desired energy to travel a curved route between the hemispheres to a detector on the far side.

Adjusting the voltage enables the IBS to sample ions of different energies or speeds. Timing the arrival of ions will permit scientists to determine the spatial distribution of the incoming ions, especially those that cause phenomena such as auroras both on Saturn and back home on Earth.

"The quantum mechanical transistor is the equivalent of turning on a light bulb without closing a switch," said Jerry Simmons, leader of the Sandia development team. "Electrons tunnel from path to path through a barrier that, according to classical physics, is impenetrable.

"Physicists use the term tunneling to describe an effect in which particles, like electrons, appear in places where they theoretically should not be able to go. In effect, they have tunneled under an energy barrier the same way cars use a tunnel to appear at a new location without having to drive over an impossibly high summit. The atomic-scale effect is explained only by quantum mechanical principles.

"We have demonstrated real circuits that work and are easily fabricated," said Simmons. The double-electron-layer tunneling transistor (DELTT) promises significant improvements in computer speed and sensor accuracy. It could run at 1 trillion operations per second, roughly 10 times the speed of the fastest transistor circuits today. The device also runs at extremely low power—tens of millivolts and microamperes—compared with the few volts and milliamperes needed by transistors now in use.

Sandia, which has applied for a patent on the DELTT, is looking for industrial and academic partners. Meanwhile, researchers are tackling some of the engineering problems that prevent commercial use of the device—such as making it compatible with existing electronics and increasing the maximum operating temperature from its current —196°C. "The rate of improvement indicates that the transistor should be operating at room temperature by next year," Simmons added. "I think we'll have prototypes of useful devices in a year or two."

Engineers in the Vehicle Systems Research Department of the Southwest Research Institute (SWRI) in San Antonio are tackling this problem by using thermal-imaging techniques to rapidly and accurately identify energy-wasting hot spots, unpredictable gradients, and transient behaviors. This project is being cosponsored by the Sacramento (Calif.) Municipal Utility District and the Defense Advanced Research Projects Agency in Washington, D.C.

To simulate driving conditions, SWRI engineers place advanced batteries in climate-controlled chambers and connect them to a personal-computer-programmable testing system that delivers the power being tested into the local grid. Infrared thermal-imaging cameras from Inframetrics Inc. in Billerica, Mass., convert heat radiated by the battery into light to create images indicating areas of varying temperature.

SWRI uses thermal-imaging equipment in place of thermocouples that typically measure temperature distribution on a battery. The drawbacks to placing thermocouples on different points of a battery include high labor costs and interference with measurements. In addition, thermocouples may not register peak temperatures, making it difficult to detect a battery nearing its heat limit.

The first phase of vehicle-battery testing at SWRI has been completed. Engineers have proposed a second phase of tests that will combine infrared thermal imaging and computational fluid dynamics to determine how adjusting the arrangement of the battery pack or providing cooling flow can be used to keep optimum battery temperatures during operation.

CFM International, the General Electric/Snecma consortium, is the current market leader. The new powerplant could enter service in 2002, though P&W has yet to line up any customers.

"The PW8000 geared turbofan is the next leap in engine technology," said P&W president Karl J. Krapek. "This engine, an extension of our PW6000 family, reduces operating costs as much as 10 percent, reduces fuel burn 9 percent, cuts noise levels 30 decibels, and boosts reliability by eliminating more than half the airfoils in the compressor and turbine sections."The new turbofan, which will produce 25,000 to 35,000 pounds of thrust, is the result of more than 10 years of research by the company and an investment of $350 million since the mid-1980s. The 56-inch-diameter engine features an 11:1 bypass ratio and a 40:1 overall pressure ratio.

The PW8000's fan, which produces most of the thrust, is driven through a 3:1 reduction gearbox, rather than being directly connected to the rest of the engine.

In general, fans operate better at slower speeds, while compressors and turbines work better at faster speeds. The engine will have 40 percent fewer stages than a comparable conventional turbofan, and 52 percent fewer compressor and turbine airfoils—lowering operating cost up to 10 percent and maintenance costs nearly 30 percent.

A typical 120- to 180-passenger aircraft using this technology will return about $600,000 in lower costs and improved productivity annually, it was claimed.

According to company spokesmen, extensive development testing coupled with advances in gear design and lubrication systems have resulted in a compact, 32,000-horsepower gearbox with an efficiency of 99.5 percent; and a heat load less than half that originally predicted.

A better understanding of laser applications could lead to the development of a downhole laser drilling machine, laser-assisted drill bits for both conventional and slimhole (coiled-tubing) applications, a laser perforating tool, and side-track and directional laser drilling devices.

GRI will manage the technology-transfer project and the Colorado School of Mines will be the primary contractor. Subcontractors are Solutions Engineering, the Massachusetts Institute of Technology in Cambridge, and Phillips Petroleum Co. in Bartlesville, Okla.

Two high-energy lasers developed under the Strategic Defense Initiative will be used in the testing: The Mid Infrared Advanced Chemical Laser (MIRACL), at the Army's High Energy Laser Systems Testing Facility at the White Sands Missile Range, N.M.; and the Chemical Oxygen-Iodine Laser (COIL), at the Air Force Research Laboratory, Phillips Research Site, at Kirtland Air Force Base, N.M.

AlliedSignal Communications & Sensor Systems in Redmond, Wash., has acquired Tensor Inc. A formerly privately held company based in Austin, Tex., Tensor manufactures orientation tool systems that guide drilling equipment to underground oil and natural-gas deposits. AlliedSignal manufactures inertial sensors, a key enabling technology for measurement-while-drilling tool systems. AlliedSignal's accelerometers and downhole sensors provide information for geo-steering directional drilling to underground deposits.

ABB Industrial Systems Inc. in Rochester, N.Y., has been awarded a $28 million automation contract for a refinery near Cartagena, Colombia, that is owned by Empressa Colombiana de Petroleos (Ecopetrol) in Bogota, Colombia. ABB will provide its Advant open-control system integrated with field instrumentation, analyzers, advanced process control, in-line blending, a refinerywide information system, and engineering and contracting services.

EV Global Motors in Los Angeles, makers of electric-powered bicycles, and Energy Conversion Devices subsidiary Ovonic Battery Co. in Troy, Mich., developers of nickel metal-hydride batteries, are joining forces in an effort to commercialize "light electric vehicles for personal transportation."

National Technical Systems Inc. in Calabasa, Calif., has been selected by the National Institute of Standards and Technology to evaluate current National Institute of Justice standards for the ballistic resistance of police body armor.

The Georgia Institute of Technology's School of Electrical and Computer Engineering in Atlanta has developed a new type of magnetically actuated micro-relay that can be batch produced using established micromachining techniques. The devices, which are smaller than a dime, have set records for their low contact resistance and ability to switch large current loads. Potential applications are in automobile electronics, test equipment, and other areas where low actuation voltagesare required.

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