Technology at a Glance is a quarterly newsletter from the National Institute of Standards and Technology reporting on research results, funding programs, and manufacturing extension and technology services. If you have comments or general questions about this newsletter or if you would like to receive the four-page, color newsletter in hard copy, please email your mailing address to Gail Porter, editor, or call (301) 975-3392. About Technology at a Glance.
Modeling Blends Science with Art
Science or art? The question has plagued medicine, meteorology, and other fields since the times of Aristotle. But the two need not be mutually exclusive, as shown by recent NIST research to improve understanding of Bose Einstein condensates.
A Bose Einstein condensate, or BEC, is an unusual form of matter, a collection of about 1 million atoms all at exactly the same energy level, behaving exactly alike. BEC atoms are to a cloud of atoms what a laser is to a light bulb. Since BECs first were observed in 1995 at JILA by NIST and University of Colorado scientists, physicists worldwide have devised experiments to probe their unique properties. One question to be answered: Are BECs a superfluida sort of liquid/gas that flows without friction?
NIST theorists proposed a test of superfluidity of BEC. The NIST test would spin a BEC in an elliptically shaped trap. If BEC behaved as a classic fluid (such as water), it would form a single vortex in the center of the trap as it spins. However, if it were a superfluid (such as liquid helium), it would resist rotating completely until the angles forced on it by the elliptical trap gave rise to an even number of well-organized quantum vortices.
A NIST simulation of the experiment performed through the wonder of mathematical modeling (see graphic above) clearly produced these vortices and, with the help of NIST scientific visualization specialists, serendipitously created an image that is as beautiful as it is informative. What remains is for experimentalists to pick up the gauntlet and test the theory in the laboratory. The JILA team already has produced BEC vortex states under different circumstances.
Contact: Charles Clark, firstname.lastname@example.org, (301) 975-3709.
A Laser Ruler For Paint Films
A new laser-based measurement technology now in final factory trials shows promise as a solution to a long-vexing problem on auto assembly linesmeasuring the thickness of paint layers.
The new instrument, developed by the Autospect Division of Perceptron Corp. with cost-shared funding from the NIST Advanced Technology Program, offers better analysis and control of a complex and essential part of auto production. There are literally dozens of variablestemperature, humidity, paint fluid flow, booth air flows, and many morethat affect the application of paint to auto bodies. But manufacturers can neither tell how important each variable is, nor optimize the process for best results, until they can measure how much paint is actually on the car.
Todays paint thickness measurements are made after several layers of paint have been sprayed and dried. Manufacturers can measure the film thickness on about two cars a dayabout 250 individual measurements per car.
At a typical plant only a fraction of a percent of production can be checked, far too slow to build up enough process-control data. By the time measurements uncover a process problem, it already has affected hundreds of car bodies.
Autospect/Perceptron believes the answer is a non-contact, non-destructive probe using laser ultrasonics. A short, intense burst of light from a probe laser heats a small area of paint, setting up ultrasonic waves in the film. It rings like a bellthe thicker the film, the lower the frequency. A second laser beam is reflected from the paint surface, the frequency of its light subtly shifted by the ultrasonic wave. The technique is amazingly precise. With a typical film thickness of 0.0035 of an inch, the system consistently measures it to a standard deviation of 0.00001 of an inch (0.25 micrometers for dry films). Autospect engineers expect to be able to make 100 measurements per second per 100 cars under production conditions. Bonus feature: since the technique uses light, the beams can be brought to and from the paint chamber using optical fibers, eliminating any sparking hazards in an environment of potentially explosive paint fumes.
The current task is to verify the accuracy of the system not a trivial problem, since there are no current methods for measuring the thickness of wet paint that can be compared to it. Autospect hopes to achieve an accuracy of 0.00005 of an inch (1.27 micrometers.)
Contact: Tim Noppe, email@example.com, (734) 414-4703.
NIST Helps Ensure Good X-ray Vision
When the orbiting Chandra X-Ray Observatory took its first image in August, the worlds astronomers were astounded. Chandra, the largest and most sensitive X-ray telescope ever built, had captured the aftermath of a gigantic stellar explosion with what might be a neutron star or black hole at its center.
Two groups of NIST researchers have reason to share with NASA in the success of the Chandra mission. The first group of microscopy experts helped ensure the accuracy of a key element of Chandras spectrometer, the diffraction gratings. A diffraction grating is an array of finely spaced lines that separates electromagnetic radiation like X-rays into a range of wavelengths, just like a prism separates sunlight into all the colors of the rainbow. The spacing of the lines in a diffraction grating determines the size range of wavelengths it can separate and is critical for accurate spectrometer readings of X-ray frequencies. The Chandra diffraction gratings were measured against a super accurate pitch standard calibrated by the NIST-developed Molecular Measuring Machine (known as M3). This metrology device, nicknamed the worlds ultimate ruler, has a measurement range some 250,000 times greater than most scanning tunneling microscopes.
The second group of NIST physicists designed, built, and tested a double-crystal monochromator that was used preflight by NASA to calibrate Chandras X-ray optics and detectors. The unique NIST device helped define the sensitivity and energy response of the telescope to incoming X-ray photons. Thanks to this calibration, NASA scientists are assured of correctly interpreting Chandras data.
Contact: John Kramar, firstname.lastname@example.org, (301) 975-3447.
Electronic books soon may find a new audience. NIST engineers have developed a Braille reader that can transform the text of e-books into Braille.
NIST researchers developed the Braille prototype as a possible low-cost alternative to conventional electronic Braille readers. NIST spent about $200 on materials for the machine. Braille readers typically carry price tags ranging from $10,000 to $15,000. Much of the cost savings are a result of a new design approach. The NIST reader (see photo above) uses only 12 actuatorsthe mechanical devices that form Braille letters. Commercial Braille readers usually have hundreds of actuators.
The NIST reader employs software to translate text into Braille and features variable speed that allows people to read faster or slower. NIST is now seeking to transfer the technology to the private sector to bring the benefits of e-books to the blind and visually impaired.
During the past year, NIST also has been working with the e-book industry to develop voluntary standards that will facilitate the growth of the industry. A group of publishers, e-book manufacturers, and software developers announced an agreement to adopt the Open Electronic Book 1.0 Specification in September at the second annual Electronic Book Workshop, sponsored by NIST.
Contact: Victor McCrary, email@example.com, (301) 975-4321.
Baldrige Winners Share Quality Tips
The newly named recipients
of the 1999 Malcolm Baldrige National Quality Award STMicroelectronics,
Inc.-Region Americas (Carrollton, Texas); BI (Minneapolis, Minn.); The Ritz-Carlton Hotel
Company L.L.C. (Atlanta, Ga.); and Sunny Fresh Foods (Monticello, Minn.)will present
details of their exceptional business and performance practices at the Quest for
Excellence XII conference, on March 12-15, 2000, in Washington, D.C.
The registration fee for the conference is $845 if submitted by Feb. 11, 2000, or $945 after that date. To register, contact the American Society for Quality and Participation, (800) 733-3310, fax: (513) 381-0070, firstname.lastname@example.org.
Contact: Baldrige National Quality Program, (301) 975-2036 or www.quality.nist.gov.
Meteorite Sports Supernova Dust
Back in the true dark ages, before the solar system was formed, a supernova explodes. Billions of years later, a chunk of rock crash lands in Murchison, Australia. The connection? A collaboration among NIST, NASA, and university researchers has determined that dust grains in the Murchison meteorite may have come from an ancient supernova, arriving there by a light-years-long journey through interstellar space.
They reached this conclusion by mapping the isotopic ratios of elements in the dust. Isotopes are atoms of an element that have different atomic weights depending on the number of neutrons in the atom. All Earth-based silicon, for example, has the same mixture of isotopes. The Murchison research group found that this isotopic mixture is different for silicon and magnesium in some of the meteorites grains. This is a tell-tale marker of a supernova and could not have come from within the solar system.
NIST researchers examined the meteorite grains with a time-of-flight, secondary ion mass spectrometer (TOF-SIMS). A beam of ions was scanned across the sample, knocking charged atoms into a long chamber. Heavier atoms take longer to fly the length of the chamber than lighter ones, allowing the instrument to construct a chemical map of the surface. The NIST instrument can map isotopic ratios with a resolution of about 200 nanometers (billionths of a meter.)
The TOF-SIMS images above show synthetic silicon carbide that was used as a standard material for the study. The image at the top shows the topography of the crystals, while the green areas in the images in the middle and on the bottom show the highest concentrations of silicon and carbon, respectively. Similar images were used to identify silicon carbide grains in the meteorite samples.
Contact: Albert Fahey, email@example.com, (301) 975-2185.
Natural Constants Get New Values
Few things in life are as dependable as the fundamental constants of naturethings like Plancks constant, the gravitational constant, and the charge of the electron. Nevertheless, even the fundamental constants need to be spruced up occasionally.
While the constants themselves dont really change, scientists are continually improving how well we know their values. As a result, an international committee periodically recommends new and improved agreed upon values for the fundamental constants. The international Committee on Data for Science and Technology has blessed an updated set of values for more than 300 fundamental constants. The new values are based on four years of work by NIST physicists to collect and analyze data from researchers worldwide.
The updated values are available at NISTs constants web site: physics.nist.gov/constants.
Contact: Peter Mohr, firstname.lastname@example.org, (301) 975-3217.
Dogs locate drugs or explosives by smell. Their noses are so sensitive they can detect even trace amounts of such substances that have evaporated into the air. Now, a NIST researcher has developed a chemical detector hardly bigger than a dime that may put the best bloodhound to shame. The system uses a new twist on an emerging technique called cavity ring down spectroscopy. The technique takes advantage of the fact that atoms and molecules selectively absorb laser light at very specific frequencies. A laser pulse injected into a cavity will lose intensity faster if theres a chemical in the chamber thats efficiently absorbing the light. The new NIST device replaces the cavity with a translucent cube of ultrapure silica. In normal air, the cube internally reflects a laser light pulse very efficiently, but if even a few molecules of a selected chemical land on the surface of the cube some of the light is absorbed, causing a change in signal by a detector. The laser light can be tuned to a range of frequencies for detecting a variety of chemicals. Patents for the device have been issued.
Contact: Andrew Pipino, (301) 975-2565.
In 1986, Mark Gaalswyk of rural Martin County, Minn., started producing software to help local hog farmers precisely control the mix of corn, soybean meal, barley, and other ingredients in livestock feed. Since then, Gaalswyks company, Easy Systems, has grown to 70 employees with sales of about $10 million. But, says Gaalswyk, If it wasnt for MTI wed still be just a hobby. Over the years, MTIMinnesota Technology Inc., an affiliate of the NIST Manufacturing Extension Partnershiphas helped Gaalswyk grow and manage the business, including getting a patent, setting up a manufacturing facility, and raising capital. Not only has Gaalswyks business grown, but the success of his company has strengthened the economic base of much of this rural area. People who in the past had left for better jobs are returning or staying to work for Easy Systems or to start their own companies, increasing housing demand and property values.
Contact: MTI, Dean Neumann, email@example.com, (612) 373-2900, or MEP, 1-800-MEP-4MFG.
About 100 American firefighters die in the line of duty every year, and another 5,000 or more are seriously burned. The number of deaths and injuries has held steady for two decades despite significant improvements in the protective clothing firefighters wear. Many firefighters report that they do not realize how seriously they are being injured until after they get out of their protective gear. Working in collaboration with manufacturers of protective gear, NIST researchers are investigating this problem with a new device that measures the effects of fire and heat on protective clothing. NIST developed the device after extensive interviews with firefighters. It enables precise measurements of temperature changes that take place in the three layers of protective clothingthe outer shell, moisture barrier, and thermal liner. The thermal test apparatus is believed to be the first of its kind in the world. NIST researchers believe the testing will lead to improved standards for protective gear and better training methods for firefighters.
Contact: Randy Lawson, firstname.lastname@example.org, (301) 975-6877.
At age one month, two orphan polar bear cubs at the Denver Zoo Snow and Klondikedeveloped rickets and bone fractures due to a vitamin D deficiency. Zoo veterinarians quickly modified their diet, and the cubs, who are now full-grown and thriving at Orlandos Sea World, began to heal. But the zoo vets kept working on the vitamin D problem in order to better understand the bears nutritional needs. To help solve this puzzle, the Denver Zoo turned to NISTs National Biomonitoring Specimen Bank. This bank holds tissue specimens from seals, sea lions, and whales collected on Alaska native subsistence hunts by the Alaska Marine Mammal Tissue Archival Project. NIST provided tissue samples from seals, the normal prey of polar bears, to the Denver Zoo for analysis of vitamin D content. The banking of marine mammal tissues, which has been taking place since 1987, will help scientists monitor changing levels of pollutants over time. Helping solve the vitamin D puzzle was an unanticipated benefit of the tissue banking project.
Contact: Paul Becker, (843) 762-8503.
ATP CompetitionThe NIST Advanced Technology Program has announced a new competition to select challenging, high-risk R&D projects that accelerate the development of path-breaking new technologies important to the economy. The program expects to have approximately $50.7 million available in fiscal year 2000 for first-year cost-shared funding of new projects that can run as long as five years. The deadline for full proposals to the competition is 3 p.m. Eastern time on Wednesday, March 8, 2000.
Contact: (800) ATP-FUND or visit the ATP web site at www.atp.nist.gov.
Measurement DatabaseNIST and the International Bureau of Weights and Measures near Sèvres, France, recently unveiled the International Comparisons Database, a new tool for resolving measurement-related questions and disputes. Developed by NIST, the database will allow companies, regulators, and others to evaluate the equivalence of calibrations and other measurement services performed by national metrology institutes in nearly all parts of the globe. This will make it easier for businesses and other organizations to prove compliance with the measurement-related requirements of regulations and standards, which affect an estimated 80 percent of global product trade. The new database is available on NISTs web site at icdb.nist.gov.
Steel EmbrittlementAt a recent conference held at NISTs Boulder, Colo., laboratories, researchers from universities and government laboratories in the United States, Europe, and Japan described programs for developing nondestructive techniques for detecting embrittlement in the steels used for nuclear reactor pressure vessels. Reports at the conference detailed how researchers are using very sophisticated microscopy techniques to determine the mechanisms of embrittlement on the atomic level and lay the foundation for developing nondestructive testing procedures. They hope that such procedures will improve maintenance of existing nuclear power plants and increase safety.
Contact: George Alers, (303) 497-7899.
NIST is an agency of the U.S. Department of Commerce's Technology Administration. NIST promotes US economic growth by working with industry to develop and apply technology, measurements, and standards. Technology at a Glance is produced by Public and Business Affairs, NIST, 100 Bureau Dr., Stop 3460, Gaithersburg, Md. 20899-3460. Any mention of commercial products is for information only; it does not imply recommendation or endorsement by NIST. Technology at a Glance Editor: Gail Porter, (301) 975-3392, email: email@example.com. For patent information, call (301) 975-3084.