Thursday, December 9, 2010
From Spoiling Chicken to Spoiling Terrorism: A Tour of the National Institute of Standards and Technology
By Dana Scruggs
On a gorgeous autumn day in the Colorado Rockies, an enthusiastic group of translators from around the world gathered in Denver to catch the bus to Boulder for a tour of the National Institute of Standards and Technology (NIST), on October 21, 2010. The tour had been arranged by Karen Tkaczyk as one of the preconference activities of the 51st Annual Conference of the American Translators Association. The 20 or so of us who participated are certainly thankful for her efforts.
Scientific information without end, data that defy imagination, mind-boggling facts, the furthest reaches of physics, chemistry, metallurgy, and electronics, not to mention lasers, clean rooms bathed in yellow light, the mystical atomic clock, superconductors, absolute zero, nanotechnology, quantum voltage, devices and computing – this is merely a sampling of the provocative concepts we found ourselves immersed in during our 2-hour tour of the NIST Boulder laboratories. The facility itself exudes a "way-back" feel, having been dedicated by President Eisenhower in 1954. The stark contrast between the somewhat bleak interior design and the prodigiousness of the work being conducted therein could not have been more pronounced. It is rarefied work being performed in a rarefied atmosphere, figuratively and literally, since Boulder sits at 5430 feet above sea level. Directly behind the facility the iconic Flatirons soar nearly two thousand feet into the sky and runners can be seen traversing the trails that extend along their base.
I will not attempt to list all of the facts and information we learned during our tour since much of it can be found on the Internet (www.nist.gov). I also highly recommend the video "What is NIST?” as a great overview of the impressive mission that defines this agency (http://www.nist.gov/public_affairs/overview_video.cfm).
To paraphrase two statements made in the above-cited video, NIST is a group of "very smart and dedicated engineers and scientists who are making measurements and standards that affect our lives positively every day”. It is a federal research agency – part of the U.S. Commerce Department – that is “working to improve our nation’s economy and quality of life”.
Now that I have toured a NIST facility, I can say that I wholeheartedly concur with these statements. I was very impressed by the depth and variety of talent represented among the relatively small population of only 350 employees of NIST Boulder. The scientists and engineers who work there perform research at the furthest edge of science and engineering to develop applications for use across the entire spectrum of human activity, from the mundane to the abstract. NIST won the Emmy Award in 1980, for instance, for developing closed captioning. At the other end of the developmental spectrum, NIST scientists co-created the Bose-Einstein condensate (in 1995), which is the fifth state of matter and the potential of which is still unknown.
Much of the work underway at NIST assists in homeland security efforts. Specifically we learned that the “puffer machines” (explosives trace detection portal machines) we encounter as we go through airport security were developed by NIST. The materials reliability lab in Boulder tested pieces of steel beams recovered from the fallen World Trade Center to learn how to improve the safety of future buildings. The events of that day have prompted yet another project currently underway at NIST, namely that of synchronizing communication systems for first responders.
Our group met with four specialists in their laboratories, where we learned about the atomic clock, quantum devices, testing hydrogen pipelines for safety, and thermophysical properties testing.
Of the many endeavors underway at NIST Boulder, the atomic clock is certainly one that captured our imagination. It is referred to as NIST-F1 and is the world’s most accurate standard for measuring the length of the second. All U.S. civilian time and frequency are based on this standard.
Exactly how accurate is the atomic clock? Get a load of this: NIST-F1 is off by one second every 80 million years. Drop that factoid at your next cocktail party to liven things up! And, when you send out the invitations to that cocktail party, be sure to invite Steve Jefferts, the overseer of the NIST atomic clock. He is irrepressively exuberant. We were told that he has appeared on NOVA, contributes to the Web site “How Stuff Works”, and that we should simply “Google” his name and enjoy all of the hits we get.
NIST-F1 provides accurate timekeeping for practical use in our everyday world. The NIST server responds to about 3 billion automated requests each day for atomic time, e.g. to update the time on our personal computers.
A key concept we encountered during our visit to the atomic clock lab was the definition of time. The "time" output by the atomic clock is defined by a certain number of cycles of electromagnetic radiation emitted by the cesium atom as it switches between its two lowest energy states. This “certain number of cycles" is about 9 billion.
Every passage of 9 billion cycles is deemed to be one second. Why? Because the “cesium second” is identical in length to the second as it was defined in 1967 when this new (atomic) method was implemented. Dr. Jefferts told us that the second used to be defined as a certain fraction of the time it took for the Earth to make one complete revolution about the sun. I find it fascinating that we have switched our calibration point for the second from one of the largest objects in our immediate universe, the sun, to one of the smallest, the cesium atom.
Heady stuff, this visit to the atomic clock laboratory! Yet the lab, the atomic clock, and Dr. Jefferts were as unpretentious and robust as they could be: the configuration of the atomic clock itself, comprising lasers that cool the cesium atoms to a few millionths of a degree above absolute zero, and the tower in which cesium atoms are bombarded with microwave radiation to change their energy states is protected behind hanging strips of thick, transparent plastic like those that hang in the entrance to a walk-in freezer in a warehouse. We did not have to wear hair nets or protective clothing. The air inflow into the lab has been redirected away from the atomic clock set-up using a cardboard box duct-taped over the vent near the ceiling. Dr. Jefferts joyfully oversees the device that provides accurate time-stamping for billions of dollars of financial transactions every day, among other portentous tasks, in a comfy pair of Birkenstock sandals and may likely use as transportation to and from work one of the myriad of bicycles we saw parked in the bike rack outside the building.
Hyper-accurate timekeeping enabled the development of the global positioning system (GPS). We were told that the accuracy of GPS for civilian use is +/- 10 cm at the range between a satellite and a point on the Earth (such as your car). Military applications of GPS, however, must account for tremendous velocities such as that of a fighter jet or a missile and are much more accurate.
The puffer machine mentioned initially was developed by the thermophysical properties division of NIST. The scientist in that laboratory, a young woman, Dr. Tara Lovestead, described how those machines can detect a single molecule of TNT or C-4 on a person. Her laboratory is developing a technique to detect volatile fire retardants in car interiors, for instance. She showed us a chunk of plastic material that had been taken from a car dashboard. This type of material, which is commonly used in our automobiles, is saturated with a fire retardant for our safety but which ironically may be harmful to our health as it is slowly released inside the car.
Dr. Lovestead also reminded us about the "plastic bottle" scare we experienced a few years ago, when we were told to avoid drinking fluids from bottles made of biphenyls because that chemical was carcinogenic and could leach into the beverage. Her lab tested biphenyls in plastic bottles and determined that they did not pose any danger to our health. We recognized how successfully the media had created an alarming story.
A current project underway in her laboratory involves developing a device for monitoring food spoilage. She demonstrated how this handheld puffer device tests the gas that forms in packages of chicken commonly sold in supermarkets. Meat inspectors may someday use Dr. Lovestead’s invention to monitor the safety of our food supply.
Our next stop took us to the hydrogen pipeline testing facility, where James Fekete showed us a section of a pipeline that had been cut open and etched with a minor crack. He said the next step would be to apply enough force to the crack to break the pipe apart. The objective is to develop a pipeline made of a material that can successfully conduct hydrogen gas and safely withstand earthquakes and other immense forces. Hydrogen is an attractive fuel source because it burns cleanly without carbon emissions and can be derived from domestic sources. But containing it within pipelines poses numerous challenges which this laboratory is attempting to overcome.
Dr. David Rudman, Quantum Devices Group Leader, described his group’s research into superconductors and nanoelectric circuits. A superconductor is a material that conducts current with no resistance, although it must be cooled to extraordinarily low temperatures to do so. He was especially keen on "Josephson junctions" which are composed partially of superconducting material. The written summary of his talk mentions that his group develops complex circuits containing up to 32,000 Josephson junctions. We may not understand what these devices are now, but I suspect they will make an impact on our lives some day, thanks to the work being done at NIST. (Remember: You heard it here first!)
Dr. Rudman also mentioned, as an aside, that their group has developed the capability to examine spent Iranian fuel rods from space and determine if they’d been used for bomb-making or not. Hearing that definitely made my day. Another project his group is working on aims to measure a single photon. A photon is the most fundamental unit – or packet – of light, and we therefore say that a photon is a quantum of light. Examining this definition may help us to better understand the work being done in this laboratory.
“Quantum Voltage” was the descriptor printed on a nameplate hanging by an office in this area. As my mind wrestled with this abstruse concept, we continued our tour and eventually passed by an office belonging to someone with the faux title “Stunt Double”. Levity and good nature abounded throughout the NIST facility and among everyone we met there.
Witnessing our nation’s highest level tinkerers in action at NIST Boulder made me feel quite proud and gave me a sense of well-being. Above the fray of alarmist talk about national security, energy dependence, food safety and other issues, hundreds of dedicated scientists calmly go to work every day and apply science and engineering for altruistic purposes on our behalf.
Special thanks to Dr. Karen Tkaczyk for arranging this tour! We also owe a debt of gratitude to our tour guide, James Burrus, Public Information Officer for NIST Boulder. He did an excellent job of making the mysteries of NIST accessible to all of us.
Dana Scruggs is a German-to-English technical translator who had the good fortune of living in Boulder, CO during her collegiate years at the University of Colorado. Her business Web site is: www.DSTranslations.com