During daily wash-downs, the clean-up area feels more like the Amazon basin than the Canadian capital, with relative humidity typically exceeding 90 percent. Ottawa's Carmichael Engineering Ltd. worked with Roswell, Ga.-based Dectron Internationale to design an HVAC system that improves workers' comfort and reduces the plant's hot water bill by thousands of dollars per year.

Canadian hospital cooks toil in greater comfort in this kitchen cooled and dried by a Dectron WaterWise air conditioning system.

Carmichael Engineering installed a humidity sensor manufactured by Honeywell of Apple Valley, Minn., in the plant's wash-down area to maintain 50 percent relative humidity. The device, called a humistat, monitors humidity so that if it reaches the preset value, it will activate the customized Dectron WaterWise air conditioner mounted on the plant roof.

The 10-ton-capacity WaterWise draws moist air out of the wash-down area through specially fabricated aluminum ducting wrapped in 1-inch-thick insulation with an aluminum vapor barrier that prevents premature condensation. The air conditioner sends cooler, drier air through conventional galvanized sheet metal ductwork. This air also keeps plant temperatures between 70° and 76°F, despite the heat generated by four large Europa baking ovens and several commercial stoves.

The WaterWise also reclaims the heat from its compressor and the cooling process, and uses it to heat up to 280 gallons of water per hour of operation. HFS uses this hot water to save about $7,000 per year, meaning the HVAC system can pay for itself in 18 months.

Thanks to trademark protection, a blue screw now proclaims, "Imitators, beware."

Registering blue as a trademark was an important step, according to Max Dorflinger, Nylok's president, because it protects the company's customers from using blue self-locking patches or pellets from other manufacturers that might be of inferior quality. "Nylok is now the only company legally allowed to use the color blue for its nylon self-locking elements," Dorflinger said.

In the Nylok process, self-locking nylon is spray bonded to the threaded portion of a fastener. Once mating threads are engaged, the self-locking element compresses, creating a counterforce. The fastener can be reused without replacing the nylon.

The new compound, Ryton R11-520BL, has a volume resistivity of 104 to 106 ohm-cm, a measure of the material's ability to bleed off any static electrical energy created in manufacturing steps or by friction between two parts. (Common Ryton PPS compounds have a volume resistivity of about 1014 ohm-cm.) The new grade is a "more conductive material to prevent the levels of static buildup that could lead to disastrous discharge when they are grounded," explained Ryton PPS general manager Bill Beaulieu.

Static electricity is created when voltage is applied to the part or when certain materials rub together. For example, a person walking across a carpet on a dry winter day collects static electricity. The potential built up isn't noticed until the person is grounded, when the electricity is released with a noticeable "snap."

In computer or automotive instrument connectors, the shock can destroy delicate instrumentation. ESD materials slowly bleed off potential energy to prevent sudden static discharge damage.

The company said the 40 percent glass-filled compound can be used to produce small, thin-wall parts, such as electrical housings and sensors. Typical electrical applications include business machine parts, hard disk

drive components, electronic packaging, and chip carriers. Automotive applications include sensors and measurement devices, underhood component housings, and fuel line connectors.

The WineMaster climate control system helps delicate vintages preserve their bouquet.

The control unit is wall-mounted directly below the ceiling in modern, impromptu wine cellars that are often set up in the unused space within basements, garages, or under stairwells. The unit is connected to household current. Operators use a built-in thermostat to program the WineMaster to provide the optimum aging temperature. The unit accomplishes this by circulating warmer air during the winter, and cooler air during the summer, to prevent the sudden temperature swings that can damage wine. The homeowner can examine a built-in thermometer to confirm if the proper temperature is being provided.

An additional advantage the WineMaster provides by circulating cellar air is that it prevents the air from becoming stale, and minimizes the temperature between the floor and ceiling.

The Fondis engineers designed the WineMaster to automatically reduce excess humidity and condensation, thereby reducing the growth of mold. The control unit's design muffles its own vibration so as not to disturb the sediment in the bottles because this can also harm the wine. The WineMaster is available in three models to control the environment in spaces ranging from 353 to 1,750 cubic feet, which are capable of holding approximately 1,000 to 3,000 bottles.

In the procedure, researchers cut 1-cm squares of austenitic sheet stainless. Following grinding and polishing the specimens to a 0.25-micrometer finish, the researchers viewed them under X-ray diffraction to verify the presence of austenitic and mar-tensitic structures.

After placing each sample in a sodium nitrite solution, the researchers charged them with a series of electric pulses. The pulses consisted of a repetitive sequence of cathodic and anodic treatments. That is, first the power supply pushed electrons into the metal; then it drew electrons away from the metal, Burstein explained.

Following three hours of repetition, the samples, viewed again through X-ray diffraction, showed a complete lack of the martensitic structure while the austenite remained intact.

The metallurgists were able to achieve the same reduction of martensite without the electrochemical process, but they had to heat the samples above 750°C, Burstein said. Also, they attempted to anneal the samples using anodic or cathodic treatments alone, but martensite remained. The researchers concluded that electrochemical annealing resulted from the combined cathodic and anodic pulses, Burstein said.

Just what mechanism induces the electrochemical annealing is still unclear, according to Burstein. What is known is that electrolysis separates water into oxygen and hydrogen during the cathodic portion of the pulse. The hydrogen atoms enter the metal and strain the lattice to change it at the microstructural level, he explained.

For the anodic portion of the pulse, the metal passivates by oxide film growth, a phenomenon that is well-known in stainless steel, Burstein said.

The crutches are claimed to be 60 percent lighter, 20 percent stronger, and 90 percent quieter than conventional aluminum crutches. "Current crutches are heavy, weighing about 5 pounds per pair," said Steve Donaldson, materials research engineer at the Air Force Research Laboratory. "At the same time, they become terribly noisy."

Composite crutches are 60 percent lighter and 20 percent stronger than aluminum ones.

Conventional crutches have a double, telescoping design that is adjusted to individual height using spring-loaded pins that pop out to the holes in the outer tube, explained Donaldson. "In a short time, these holes elongate, allowing motion between the pin and the hole—and lots of noise." Other disadvantages of current aluminum crutches are that they wear out relatively quickly and have an institutional, medical look, he added.

The new composite crutch has primary load-bearing tubes that are table-rolled from graphite/epoxy prepreg and thermally cured. The reinforcement is a medium modulus carbon fiber that is frequently used in sporting goods applications. In hand rolling, unidirectional carbon-reinforced tape that is impregnated with epoxy resin is manually rolled around a mandrel in a 0- to 90-degree fiber orientation, and then cured in an autoclave. Hand rolling is suitable for prototyping and low-volume production, said Donaldson.

The central intersection fitting, die cast from aluminum, has three protruding tubes over which the composite tubes slide, and to which they are bonded with aerospace grade structural adhesive, said Vernon Bechel, materials research engineer at the laboratory. "This part is designed so that in the rare event the handgrip is overloaded, the aluminum will yield before the composite breaks, clearly indicating to the user that the crutch should be replaced."

Customers will provide two dimensions—the distance between the end of the rubber foot and the handle, and from the handle to the middle of the cuff. The manufacturer will then pull two prefabricated tubes, cut them into three measured pieces, bond the pieces together with adhesive, cure them, and add the last few parts, rubber foot, cuff, and foam grip.

The new crutches will be custom made, and will sell for about $500 per pair, according to Joyce Young, president of Ergonomics Inc. She plans to expand the use of composites into other ambulatory aids and is investigating various production processes, such as pultrusion.

A combined power plant being built in Baku, Azerbaijan, will use two GT8C2 gas turbines manufactured by Alstom of Paris to generate 110 megawatts of electricity and 400 tons per hour of process steam for the Azneftyag oil refinery, a textile factory, and other industrial and residential consumers in Baku. AzerEnerji will operate the power plant, which is scheduled to become fully operational by November 2001.

NEC Corp. of Tokyo and ESI Group of Paris will develop what the companies are calling the first virtual engine factory. The system will simulate the entire engine building process, from design through manufacturing, and will include casting, combustion, dynamic stress, fatigue, and lifetime analyses. The system will run on NEC's SX-5 computer.

The National Highway Traffic Safety Administration and intelligent-vehicle researchers at the National Institute of Standards and Technology are developing tests for lane-departure warning systems. The systems, available already on some trucks, will wake dreaming drivers as they drift from their lanes.

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