ON THE COVER

John Bates examines a thin-film lithium battery in the light of the nitrogen glow discharge in the vacuum deposition chamber used to produce microbatteries at ORNL's Solid State Division. The nitrogen gas reacts with lithium orthophosphate to form a new battery electrolyte film discovered at ORNL. See the article on p. 46. Photo by Bill Norris.

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ISSN 0048-1262

Editor Carolyn Krause Associate Editor Jim Pearce Consulting Editor Bill Appleton Designer Vickie Conner Technical Editing Mike Aaron Electronic Publishing Bob Eldridge Photography, Graphic Arts, and Printing and Duplicating departments Volume 25 Number Two, 1992

2 State of the Laboratory-1991: Strengthening R&D Alvin Trivelpiece Organizational changes and enhanced computing capabilities should bolster ORNL's R&D. 28 An Eye on Reactor and Computer Control Jack Schryver and Bill Knee Eye-gaze measurement technology improved by ORNL software may have fascinating uses. 36 Seeking Order in Chaos C. Stuart Daw ORNL is applying chaos theory to engineering problems such as fluidized beds. 46 Thin Films for Advanced Batteries Carolyn Krause ORNL has developed a thin-film lithium microbattery for computer memory chips. 57 Waste R&D at ORNL Diedre Falter ORNL is developing innovative environmental restoration and waste management techniques. 64 New Waste Technologies Jim Pearce 94 License Renewal for Nuclear Power Plants Claud Pugh

SIDEBARS: Aging and Safety in Reactor Pressure Vessels Component Aging Research Environmental and Socioeconomic Impacts

DEPARTMENTS 120 Pick a Number 122 Awards and Appointments 129 User Facilities-Surface Modification and Characterization Collaborative Research Center 131 Educational Activities-ORNL-ORAU partnership in education 134 R&D Updates-Detection of pollutants in fish aided by a Laser; Bioprocessing R&D Center established; snails and stream health; wireless robots in hot cells; insights into wetland management; new batch of isotopes produced; monitor for testing wall stability; optical band absorber 144 Technical Highlights-advance in weld analysis at the HFIR; book on Integrated Forest Study; how superconductor grows shown by Z-contrast imaging; update on Advanced Toroidal Facility; 4 R&D Awards for ORNL technologies 160 Technology Transfer-new CRADAs on toxin in insulating gas, packaging of thin-film batteries, microwave sintering of capacitors, thermal performance of ceiling panels and roof insulation, computer images and geographical data for characterizing environmental conditions, and ceramic components in diesel engines; blood rotor licensed

Oak Ridge NaJional Laboratory is a multiprogram, multipurpose laboratory that conducts research in the physical, chemical, maJerilll and life sciences; infusion, fission, and fossil energy; and in energy conservaJWn and other energy-related technologies. Editor's note: On

February 6, 1992,

ORNL Director

Alvin W. Trivelpiece delivered his third

State of the

Laboratory address In his third State of the at the American Laboratory address, Trivelpiece emphasized the Museum of Science role of organizational chang and Energy in Oak and enhanced computing capabilities in supporting Ridge. The research and development. 1 - following is an updated, edited version of his talk.

2 s I look back on 1991 at Oak strengthen research and development (R&D) at Ridge National Laboratory, some the Laboratory and in this community. A famous quotations come to mind. Many of you remember-some perhaps The first is the ancient Chinese curse, "May you fondly-the U.S. Atomic Energy Commission live in interesting times." The second, from (AEC). This administratively lean and technically Charles Dickens' A Tale ofTwo Cities, is, "It was rich organization employed many scientists and the best of times, it was the worst of times." engineers in key management positions. For some These quotations certainly hit the mark for this of its years, it even had a Nobel Prize-winning past year. chemist, Glenn Seaborg, as its chairman. I suppose that if we had invented a new The AEC had a clear mission to produce Chinese calendar, 1991 would be "the Year of the nuclear weapons, enrich uranium, do fundamental Frog" because of the media attention we received research in physical and life sciences, and when some frogs left a contaminated ORNL pond advance the cause of nuclear power. To meet its and, after being run over by cars, were found to mission, the AEC used industry, universities, and be slightly radioactive. By the same token, 1990 its own facilities. It performed its mission in a was the Year of the Tiger because of the way that seems almost pastoral compared with "Because Department of Energy's Tiger Team assessment today's mode of operation. peace broke to determine whether ORNL was in compliance The AEC had many ups and downs. For out all over with environmental, safety, and health (ES&H) example, a test ban in the late 1950s resulted in a regulations. substantial cutback of activities. However, our the world, Because peace broke out all over the world, stable, reliable enemies in the former Soviet 1991 1991 qualified for a "best-of-times" rating. But I Union began firing off a bunch of weapons at suspect that some of our friends and colleagues in their test site, so the AEC's weapons production qualified for the former Soviet Union may have regarded 1991 activities picked up again. In the late 1960s, the a "best-of­ as the worst of times. The U.S. economy times" doesn't seem to be in a favorable state either. We have rating." a deficit and a foreign trade imbalance, and we certainly have an unemployment rate that is higher than desirable. The U.S. government is now under a great deal of pressure to both control spending and support projects in environmental restoration and waste management that a few years ago wouldn't even have been considered. I want to remind you of some of the events that may be responsible for our current situation. Because these events may color our attitude, we A few dozen frogs that migrated from an ORNL pond were found to should examine them and be radioactive after they were run over by cars. The incidents perhaps even adjust our attracted the attention of the news media, even though the thinking about our situation so radioactive frogs posed no health hazard unless eaten in quantity. that we are prepared to (The crushed frogs were disposed of as radioactive waste.)

Number Two, 1992 3 STATE OF THE LABORATORY-1991: STRENGTHENING R&D

report generally known as the "Ten Billion Exercise." Some of its proposed elements for making the United States energy independent actually were implemented. Bureaucratic Enrichment For the AEC, the chief issue of the day was not the energy crisis. Rather, it was the concern that people had over the AEC's dual role as both promoter and regulator of civilian nuclear power. That concern resulted in considerable pressure to break up the AEC, and, at the beginning of 1976, it was divided into the Enjoying the social hour after the State of the Laboratory address Nuclear Regulatory Commission were, from left, Clyde Hopkins, president of Martin Marietta Energy and the Energy Research and Systems, Inc.; Alvin Trivelpiece, ORNL director and an Energy Systems vice president; Herman Postma, former ORNL director and Development Administration retired senior vice president of Energy Systems; and David Reichle, (ERDA). The creation of two ORNL associate director for the Environmental, Life, and Social agencies from one is important Sciences. because it started a process I call bureaucratic enrichment. Bureaucratic enrichment profoundly affected us all. AEC fusion program enjoyed a burst of activity Suddenly, nonnuclear and other programs began because of the interest in conducting fusion to sprout up everywhere. The weapons experiments on tokamaks (conceived by the laboratories began experiencing severe cutbacks Soviets), and ORNL benefited by being one of the and considerable uncertainty, but the ERDA first laboratories to build and operate a tokamak programs were stable. However, as the political outside the Soviet Union. Those were really winds shifted in Washington, ERDA was exciting, fulfilling times when the employees of replaced by the Department of Energy in 1978. the AEC and its contractors thought their work was James Schlesinger, a former AEC chairman, important to the nation's survival. We had no became the first Secretary of Energy, and doubt, uncertainty, or anxiety about what we were bureaucratic enrichment was probably even doing. accelerated at that time. Whether that's good When I worked for the AEC from 1973 to 1975, news or bad news, I don't know; it's in the eye of Americans began experiencing lines at the gasoline the beholder. Certainly, the energy crisis is still a pumps because of shortages of imported oil-the major concern. so-called energy crisis. Dixy Lee Ray, AEC DOE started programs to build plants for chairman at that time, convened an AEC group and producing synthetic fuels. Some of the national asked it to determine ways to make the United laboratories even bought their first lumps of coal States less dependent on oil imported from for experiments related to liquefying and unstable countries; as a result, the AEC issued a gasifying coal. Americans lowered their

4 Oak Ridge National Laboratory REVIEW l

thermostats and drove 55 miles per hour. As a result of some other political events, it was suggested that DOE be abolished. DOE survived, but changes occurred, such as a reduction in a major program to build coal gasification plants, a rapid growth of weapons production, and a shift away from applied research in favor of basic research. "The 1983 Watershed Events revelation From 1981 through 1987, I served as director of about DOE's Office of Energy Research. In 1983, a woman entered my office and said, "Do you know mercury zn there are 2.4 million pounds of mercury in the the soils and ground at Oak Ridge?" I was really tempted to waters of say, "No, but if you hum a few bars, I'll see if I Fred Hartman, director of ORNL's Biology Division, can pick up the melody," but I didn't. I was chats with Trivelpiece following the State of the OakRidge certain that this was a joke or a mistake and that Laboratory address. was the several of those zeros should be taken off. It couldn't be that bad, I thought, but it turned out to Chernobyl reactor. I got caught up in all the watershed be true that there was a lot of mercury that had department's activities concerning Chernobyl as event that been spilled, although the actual number turned I helped set up new committees and reviewed resulted in a out to be 350,000 pounds. I suspect that day was documents for Congress. It was a frantic period, no better for Joe La Grone, manager of the DOE but it was necessary because of the importance buildup of Oak Ridge Field Office, than it was for me when of preventing a repetition of the Chernobyl pressure we learned about this heavy metal contamination disaster. Direct consequences of that watershed resulting from weapons production at the Oak event were the permanent shutdown of the nationally to Ridge Y-12 Plant. The news resulted in some truly N-Reactor at the Hanford Engineering clean up bad jokes about 6-inch fish that weighed 20 Development Laboratory and the temporary DOE pounds. shutdown of ORNL's High Flux Isotope Reactor The 1983 revelation about mercury in the soils (HFIR). production and waters of Oak Ridge was the watershed event As a result of the Chernobyl accident, ES&H and research that resulted in a buildup of pressure nationally to programs received increased emphasis at DOE clean up DOE production and research sites. facilities. The department began to focus on sites." Before then it was fairly easy for DOE managers identifying the facilities that needed to be to say, "Look, we are making realistic progress at cleaned up first as well as the best methods to a reasonable rate in cleaning up many of the sites remediate them. It was clear that it would be just for which we have responsibility." a matter of time before business changed. After the mercury revelation, ES&H matters Another watershed event was the surprise that received substantially more attention. Some might Admiral James Watkins, the Secretary of say that another watershed event was the 1979 Energy, experienced on Thanksgiving of 1989. nuclear power plant accident at Three Mile Island. A Federal Bureau of Investigation team came to It was serious and clearly had a profound effect on DOE's Rocky Flats Plant in search of criminal the nuclear industry and the management of environmental violations. This investigation led civilian nuclear energy programs. But I think the to the development of comprehensive Three Mile Island accident was insignificant in environmental and safety audits. These are now comparison with the 1986 accident at the called Tiger Team audits, and they are done at

Number Two, 1992 5 STATE OF THE LABORATORY-1991: STRENGTHENING R&D

DOE facilities to ensure that they are complying and DOE field office with environmental laws, rules, and regulations. managers to discuss the Many of us look back with a certain fondness problems of managing the or nostalgia for the good old days of the AEC, but laboratories. I don't think there is any way we can work as we By my recollection, it really did back then. The Laboratory staff has learned to was a unique event in the operate in its present circumstances. The AEC and entire history of any of the ERDA are gone, and the old ways of doing government energy agencies. business are not coming back. Secretary Watkins got The American public is more concerned about intensely involved, rolled up the environment than ever before. Today, the his sleeves, participated with "The public does not trust DOE. Members of the public us, got into the arguments with American want independent verification of the many facts everyone, and, although he public is we generate, and their demand for more audits clearly was the boss, he and oversight will continue. Such audits are certainly behaved in many more intrusive, invasive, and a fact of life. We are respects as an equal and concerned going to have to learn to work in this climate and worked very effectively during compete for scientific and technical programs at that period. As a result of that about the the same time. It is not easy now, and it is not meeting, several working environment likely to get any easier. committees have been set up than ever In early 1991, the on-site Tiger Team to look into new issues, and an assessment at ORNL had just concluded, and we agreement was made to before." prepared an action plan to correct some of the involve the laboratory cited deficiencies. I am pleased to report that we directors in developing and have made really good progress, and I think we writing DOE orders. have some prospects for funding for some The summit meeting may expensive projects. But correcting the deficiencies prove to be one of the really is not going to get easier either. We will important events in the history experience conflicts between the need to clean of the DOE laboratories. The things up to comply with regulations and the Secretary of Energy says he desire to operate scientific programs to serve our will meet with us periodically. customers. The second meeting was held In the Year of the Tiger, we did the right thing. in March 1992, and we By meeting our goal of surviving those difficult discussed a number of the circumstances, we are really better prepared and issues we had no time for at well positioned to work through the tough times the September summit ahead. meeting. The summit meeting focused primarily on roles and DOE Summit Meetings missions and ways to improve our laboratory performance. A watershed event that occurred in 1991 may Already the summit meeting have as much effect on the Laboratory's future as has proven to be a best-of­ any event mentioned thus far. It was the so-called times event. "summit meeting," which took place September One of the ironies is that, 17 and 18 in Leesburg, Virginia. There Secretary over the years, the laboratory Watkins urged the DOE laboratory directors to directors complained bitterly hold off-site meetings with political appointees that DOE paid no attention to

6 To make ORNL's east parking lot safer and brighter, new holophane high-tower lights have been installed, replacing the old lighting system. The new energy­ efficient lights, one of which is shown here, will provide more illumination over a larger area of the parking lot.The lighting system was installed by Allegheny Industrial Electric of Oak Ridge at a cost of $150,000.

7 STATE OF THE LABORATORY-1991: STRENGTHENING R&D

Malcolm Stocks, sitting, and AI Geist discuss computer simulations of materials properties using the multi­ processor Kendall Square system (shown in the photo), which was recently obtained by ORNL's new Center for Computational Science.

them. Well, now the department is paying attention to us laboratory directors, and because such attention creates a lot of work, we are complaining about it. DOE just can't win!

Strengthening R&D: Bureaucratic Changes An event that I hope will have some influence on the future of ORNL is the establishment of the R&D Strategic Planning Committee. The intent of this committee is to respond to a legitimate, longstanding complaint: management isn't paying any attention to the scientific and research programs at the Julie Robinson works at an engineering workstation, which can run Laboratory. Guilty as charged. complex calculations that once could be done only by large The extenuating circumstances mainframe computers. are that ORNL managers had to

8 Oak Ridge National Laboratory REVIEW concentrate on certain activities to ensure that the increasingly powerful computers. Research and Laboratory would survive the Tiger Team audit. development has embraced computers as much as True, we diverted our attention away from the commercial world. In fact, a relatively new research, but our intention now is to return to it. branch in the taxonomy of science is computing This new committee, which includes research science, which complements experimental science associate directors and division directors as well and theoretical science. as some working scientists and engineers, is a One of my concerns when I first became good group. We have met only a few times. We director of the Laboratory was that we were not are still trying to feel our way along, but I think competing very well with our sister institutions in that this approach will improve our ability to computing science, even though the Laboratory compete for funding for research projects that has more than 5000 computers of various sizes. would best use our experience and expertise. Very few individuals in the Laboratory were A new Operations Committee will try to working on problems on which progress could be improve operations at the Laboratory. This made without access to a world-class committee includes representatives from research supercomputer. As a result of this concern, I divisions and operating divisions. Its purpose is to recruited Ed Oliver and appointed him director of find ways for the people who are responsible for the Office of Laboratory Computing. Oliver; Bob operations to be more responsive to their Ward, director of ORNL's Engineering Physics customers. This committee will also look at the and Mathematics Division; AI Geist and Richard management work load and find ways to delegate management responsibilities to various groups through the empowerment of ORNL employees. A related activity is the establishment of new review committees for the operations divisions, similar to the review committees for our scientific programs. In this way, the customers who serve on a committee can evaluate a particular operating division and make recommendations for its improvement. We will also include on these committees some experts from outside laboratories and elsewhere within Energy Systems.

Strengthening R&D: Computing Capability Chuck Scott examines a tapered column of gelatin beads Besides these bureaucratic containing microorganisms that could be used for removing changes, the Laboratory can contaminants or producing chemicals. Scott is director of ORNL's strengthen its R&D by using new Bioprocessing Research and Development Center.

Number Two, 1992 9 STATE OF THE LABORATORY- 1991: STRENGTHENING R&D

Sincovec, both of Ward's division; Malcolm Energy Physics. We encourage high school Stocks of the Metals and Ceramics Division; and students to work on computers in what is turning others drafted a proposal in 1991 requesting out to be a very effective and popular program. funding under the new high-performance computing initiative that had been working Interdisciplinary through the DOE system. The competition was Research Programs very tough, because competitors with whom we were playing had great resource advantages. But, From my experience in teaching physics for because of our growing expertise in parallel about 20 years at several universities, computing, I am pleased that ORNL was one of I learned that universities have a difficult time the two sites selected by DOE to become high­ operating interdisciplinary research programs. It is performance computer research centers. Our goal difficult for two faculty members to do will be to start solving complex scientific collaborative research within one department, let problems, called Grand Challenges, using a alone across departmental lines. ORNL has its parallel supercomputer. We will first focus on share of problems, but one of them is not setting modeling the transport of pollutants in up and managing interdisciplinary research "To achieve groundwater and designing new alloys. We will programs. In 1991, in addition to the Center for receive $120 million over the next five years to Computational Science, we started or became excellence as establish and operate a new Center for involved in several interdisciplinary programs. an Computational Science, and we will recruit a First, we established the Center for Risk institution, director to manage the center. Management, headed by Curtis Travis. It is Let me comment on our success in becoming a important to understand the risks and benefits of we should computer center. It is often assumed that all it various activities, including remediation of strive to takes to win a project is a good proposal. We tend hazardous waste sites. to forget that many dedicated employees at DOE We also established the Bioprocessing Research attract more and other government agencies actually fight hard and Development Center, headed by Chuck Scott. graduate for budget items that are important for our nation. This center will develop bioprocesses that students and Members of Congress and their staffs have also economically produce fuels and chemicals from worked to ensure funding for the high­ fossil materials and renewable feedstocks, postdoctoral performance computing initiative. Many people including recycled waste material such as paper. fellows." deserve our collective thanks for bringing ORNL In addition, it will develop bioprocessing systems this opportunity. We have an obligation to do a to remove and degrade pollutants. Emphasis will good job for them and I am quite confident that be on expanding interactions with academia, other we will do so. national laboratories, and industry and on Engineering workstations are powerful technology transfer. (See "R&D Updates" for intermediate computing tools that are gaining more details.) wide acceptance. They can perform many In addition, ORNL has joined the University of calculations that once were run only on large Tennessee and the Tennessee Valley Authority in mainframe computers. Unfortunately, ORNL has establishing the Joint Institute of Energy and the less than 100 engineering workstations, whereas Environment. It will promote cooperative research some of our competitors have a few thousand. and educational programs involving all three This is one area in which we hope to improve. institutions. In this way, we can help each other Computers are also important tools for provide even better services. educating future scientists. On Saturdays, high In 1991 the HFIR completed its 300th reactor school students come to the Laboratory to attend fuel cycle. To help us celebrate, we were sort of the Saturday Academy of Computing and visited by a president of the United States. Some Mathematics. We patterned this school after the of Zachary Taylor's remains were sent to ORNL Fermi Laboratory's Saturday Academy for High- for neutron activation analysis at the HFIR to

10 Oak Ridge National Laboratory REVIEW determine if he had died of arsenic poisoning as a approved by the Laboratory's Executive historian had theorized. Neutrons were used to Committee. One of the features of the plan is that irradiate samples of his hair, fmgernails, and Oak Ridge Associated Universities will still bones, because various substances irradiated with operate the program but increase the Laboratory's neutrons give off characteristic gamma-ray visibility as the sponsor of these postdoctoral signatures that make possible a determination of fellowships. the elemental composition of the samples. Another way to attract highly capable Analytical chemists Larry Robinson and Frank researchers is through new programs such as the Dyer found that the samples contained virtually no Visiting Distinguished Scientists and Engineers arsenic. And President Bush might be interested to Program. The first Visiting Distinguished know that they had no reason to suspect broccoli Scientist is E. Ward Plummer, the William Smith poisoning as the cause of Zachary Taylor's death, Professor of Physics at the University of either. Pennsylvania and an internationally renowned surface physicist. He is going to collaborate with Recruiting and the Surface Physics and Theory Groups in the "Technology Retaining Staff Solid State Division. Through this program, we can call attention to what we are doing, involve transfer is To achieve excellence as an institution, we some renowned experts in our activities, and give really a should strive to attract more graduate students and them the recognition that they deserve. postdoctoral fellows. Many of these may fit into contact permanent positions at ORNL after they complete Interaction with sport--a way their scientific or technical education here. In this External Groups of getting way, we lower the average age of the scientific and technical staff at the Laboratory, which is We are not an island. The Laboratory staff must people from around 46. It is nice that everybody loves it here interact with people in external organizations to varwus and that we have a good stable population. But the survive. Energy Systems' Office of Technology Laboratory would benefit from having a greater Transfer and ORNL's High Temperature disciplines to number of young researchers to offer us energy, Superconductivity Pilot Center, which has 17 rub enthusiasm, and new ideas. We need a higher active agreements with industrial firms, have done shoulders turnover rate, and we should hire more young fme jobs of bringing people together to help move researchers. Laboratory developments into the marketplace­ and play a How do we go about recruiting and retaining one of DOE's goals. Technology transfer is really game zn staff? One way is to offer fellowships, such as the a contact sport-a way of getting people from nationally competitive Hollaender and various disciplines to rub shoulders and play a which Householder Fellowships. An appropriations bill game in which everybody should be a winner. everybody contains language establishing a High One good example involves a partnership should be a Temperature Materials Laboratory (HTML) between IBM and ORNL in research in high­ . " Fellowship Program, which would make the temperature superconductivity. 1f the new high­ wznner. HTML an educational vehicle for both industrial temperature superconducting materials are placed and university materials researchers. Fellowships in a magnetic field, the magnetic flux will move are a good way to attract prospective scientific under the influence of an electric current, causing staff members. We look each other over, and the material to dissipate energy. But if the some of them will stay. magnetic flux lines can be pinned-say, by some One problem I asked our Corporate Fellows to defects in the materi.al- it will continue to look at was the fact that few people know that conduct without energy loss. Working with IBM ORNL has been sponsoring postdoctoral research researchers, ORNL researchers bombarded programs. They came up with a plan for a new samples of yttrium, barium, and copper oxides ORNL Postdoctoral Program, which was (YBCO) with a beam of high-energy tin ions at

Number Two, 1992 11 STATE OF THE LABORATORY-1991: STRENGTHENING R&D

the Holifield Heavy Ion Research Facility and then placed the samples in a magnetic field at low temperatures for measurements of superconductive properties. They found that the heavy­ ion-induced defects are very effective in pinning the magnetic flux lines, especially when the magnetic field is parallel to the defect tracks. As a result, the material's ability to carry electrical current declines much more slowly in a magnetic field as the density of the defect tracks increases. ORNL and IBM researchers have demonstrated that they can The ORNL researchers were Jim improve a high-temperature superconducting material (oxides Thompson, Dave Christen, Rich of yttrium , barium, and copper, or YB~Cup7 ) by bombarding Kerchner, Brian Sales, Bryan it with heavy ions of tin at the Holifield accelerator. The Chakoumakos, and Lynn Boatner. resulting defects pin the magnetic flux lines. This pinning Such cooperation between ORNL's causes the material's ability to carry electrical current to Solid State Division and IBM helps decline much more slowly in a magnetic field as the density of increase our researchers' basic the defect tracks increases. understanding of superconducting materials and helps move IBM closer to making practical devices using these materials. Phil Childs sprays Through the Roof loose-fill insulation Research Center, a DOE into an attic to user facility at ORNL, our study the role that researchers have helped the convection plays roofmg industry understand in causing heat losses from roofs. which types of attic ORNL's find ings insulation are most effective have led to and why. Some of my changes in the colleagues still don't believe guidelines on that there is roof research in installing attic Oak Ridge. They think the insulation. most recent research on roofs was probably done about 6000 BC in the south of France when people painted the ceilings in their caves. Our researchers can explain why Minnesotans have such high heating bills even after they paid for loose insulation sprayed into their attics. It turns out that spraying some types of

12 Oak Ridge National Laboratory REVIEW loosefill insulation permits air Tyler Jenkins movement within the insulation, adjusts the resulting in natural convection. alignment of a Compared with conduction, natural silicon nitride test specimen in a convection in attic insulation can four-axis grinder. result in the escape of more heat Precise alignment from within a building to the outside. is required to In measuring the effectiveness of ensure proper attic insulation in houses during the machining winter, ORNL researchers led by Jeff tolerances, which Christian have conflffOed that natural are critical for convective heat loss in some loosefill successful tensile fiberglass insulations can be testing. Such testing will be responsible for as much as half of the done in one of the heat loss at very low temperatures. new user centers This particular piece of research at in ORNL's High the Roof Research Center is leading Temperature to changes in the handbooks on Materials installing attic insulation, a major Laboratory. accomplishment for the Laboratory. To increase our interactions with industry, two new user centers were created in the HTML. The Ceramic Specimen Preparation User Center will provide basic facilities for studying the effects of machining and fabricating ceramic specimens for use in evaluating the mechanical performance of structural ceramics. The Residual Stress User Center will seek to better understand the behavior of composites and the effects on materials of grinding, forming, joining, finishing, and thermally treating them. Another way we are helping industry is by providing our expertise on microwave processing, a rapidly growing industrial tool used for sintering ceramics, plasma processing of semiconductor wafers, and accelerating the curing of Huey S. Hsu, former ORNL researcher and a consultant to polymers. Traditionally, such American Superconductor, watches Charlie Dunn, a technician in the Metals and Ceramics Division, extract a thin ribbon of processing has been carried out at lead-doped bismuth superconducting material. This wire is fixed frequencies, which results in produced in the laboratory apparatus by rolling and nonuniform heating of materials. compressing a tube containing powder. Short superconducting Bob Lauf of the Metals and wires have been made at ORNL, and their electrical Ceramics Division and Don Bible of performance has surpassed DOE goals.

Number Two, 1992 13 STATE OF THE LABORATORY-1991: STRENGTHENING R&D

the Instrumentation and Controls Division have developed a variable frequency microwave fun:tace. This unique device, which provides a range of frequencies, uses a wide band traveling wave tube originally developed by Microwave Laboratories, Inc. (MLI), for Gerry Bunick removes the electronic warfare. Through a cover from a cooperative research and development neutron agreement (CRADA), ORNL has diffractometer he transferred the technology to MLI, plans to return to which is now manufacturing complete operation for furnace units. studies of the ORNL researchers have worked structure of with industrial researchers through the biological High Temperature Superconductivity materials at ORNL's High Flux Pilot Center to develop a lead-doped Isotope Reactor. bismuth superconducting material. By developing and using innovative powder-in-tube processing methods adaptable to continuous manufacturing processes, they have made short wires whose electrical performance exceeds the interim DOE goal for super­ conducting wire. Some of our most successful research projects start internally, from the bottom up. Our people propose projects and receive enough internal This is a model of funding to prove their ideas will work. the suggested The really successful projects grow structure of a into programs that receive funding fluorinated from DOE and other outside agencies. buckyball. ORNL and University of A few years ago, DOE started the Tennessee Human Genome program. Six of the researchers have nine human genome projects at ORNL produced were started with support from our fluorinated Laboratory Director's Research and buckyballs Development Fund. Because of the (ranging from merit of these projects, ORNL is now C F to C F ), 60 44 60 48 receiving outside funding from DOE's which may have Human Genome program. This is an applications as lubricants. important area for the Laboratory to be involved in. One current internally funded project that may prove beneficial for human genome studies is the use of

14 Oak Ridge National Laboratory REVIEW neutron diffraction at the HFIR for determining the properties of biological materials (see photograph of Gerry Bunick setting up neutron diffraction equipment at the HFIR). ORNL's Larry Hawk biology R&D will be strengthened by the demonstrates the availability of more experimental equipment at Direct Braille the HFIR for studies of the structure of Slate, a writing biological materials. tool for the blind The Director's Fund was also used to support that he and Joe Turner (left) studies of the formation of negative ions of invented. buckminster fullerenes, or buckyballs, molecules made of 60 carbon atoms that may have uses as lubricants and superconductors. Our research successes should give ORNL a major role in developing applications for buckyballs. Our internal funding is one of our most precious resources. In 1992, we may be allowed up to $10 million for internal support of research. While at DOE, I was always fascinated by the ability of the department's national laboratories to do such original and innovative work with just a few dollars. A fascinating inverse correlation exists between the quantity of dollars spent on this research and the quality of its results. On the other hand, DOE spends substantial programmatic dollars over which it has considerable control and direction, yet these programs don't seem to produce quite the same frequency of hits. There is probably a message there, but I've not figured out how to get it across in a way that would benefit government­ sponsored research. One measure for judging the performance of the Laboratory is by assessing how well others think we are doing. The Laboratory staff continues to receive its fair share of awards and honors. Such successes help establish our expertise, attract funding and personnel, and strengthen our R&D programs. Every year, our staff members continue to be elevated to the rank of fellow in numerous professional societies, such as the American Physical Society, American Chemical Society, Igor Alexeff (left), an ORNL consultant and American Association for the Advancement of professor at the University of Tennessee, and Science, ASM International, and the American David Hobson and Vinod Sikka, both of ORNL, Nuclear Society. In 1991, 32 of our staff invented the electromagnetic liquid metal inclusion members were named fellows of professional removal device.

Number Two, 1"992 15 impurities from conducting liquid metals used to make consumer products such as beverage cans. When consumers buy gasoline for their cars, they like to think they are getting the octane level they paid for. But is it possible to measure octane to determine the Paul Haubenreich quality of the fuel being purchased? Bob Lauf of the M&C Division and Barbara Hoffheins of the Instrumentation and Controls Division have developed a rapid fuel analyzer, which can measure gasoline octane and also identify spilled fuels. Their device, which includes a neural net, received an Michael Wilkinson R&D I 00 Award. Another award that is very important to us is the one given by DOE's Division of Material Science. The Department of Energy has a competition among the projects that it sponsors and, Bob Lauf and Barbara Hoffheins devised a rapid fuel analyzer for over the past three years, the applications such as detecting hazardous chemical spills. Laboratory staff has won eight awards-more than any other Herman Postma laboratory. societies; altogether, ORNL has 212 fellows. DOE Associate Awards were given in 1991 to Nine of our people were elected officers of Paul Haubenreich, a recent ORNL retiree, for his national professional societies. Election to a leadership in the International Large Coil Task; society board is usually a recognition of a Mike Wilkinson, for his neutron research person's scientific and technical accomplishments, his leadership in the Solid State accomplishments and willingness to take on Division, and his service as a member of the some mundane jobs to benefit the society. Advisory Committee for DOE's Basic Energy Among the awards we value highly are the Sciences (BES) Program and of the BES Program Ralph Moon R&D 100 awards given each year by Research & Council on Materials; and Herman Postma, former Development magazine. Perhaps the award­ Energy Systems senior vice president, for his winning innovation of 1991 that will have the leadership as ORNL director from 197 4 through most human impact is the Direct Braille Slate, 1988. In 1991, Energy Systems selected Ralph which allows blind people to write in braille Moon and Tom Shannon as Corporate Fellows and directly on paper. It was invented by Joe Turner Loucas Christophorou as Senior Corporate Fellow. and Larry Hawk, both of ORNL's Applied These individuals richly deserve this recognition. Technology Division. This invention has been nominated for the National Medal of Technology Technical Achievements and President Bush's 1000 Points of Light Thomas Shannon Award. Hawk recently received the Advanced ORNL researchers achieved some outstanding Technology Award from the International Hall of technical feats in 1991. These are summarized here Fame of the Inventors Clubs of America. and in two sidebars. Another R&D 100 Award-winning entry We have made contributions to the development works on the principle that, if a conductor and a of modular high-temperature gas-cooled reactors nonconductor are placed in a magnetic field, the (MHTGCR), which may revitalize the nuclear first will experience a force when moved but the industry. We are addressing safety concerns through second will not. ORNL consultant Igor Alexeff tests done in the furnace of our Core Conduction and David Hobson and Vinod Sikka, both of the Cooldown Test Facility, which was developed to Lou cas Metals and Ceramics (M&C) Division, have heat irradiated particles up to 2000°C for hundreds Christophorou applied this principle to removing nonconducting of hours for studies of the released fission products.

16 Oak Ridge National Laboratory REVIEW The information obtained is used to evaluate MHTGR fuel performance during accident conditions and to develop computer models of fission product releases. A portable, lightweight, accurate system for weighing vehicles in motion was developed by the Applied Technology Division. This system, which is based on fiber-optic technology, is packaged in six portable canvas cases. The system's accuracy has been demonstrated; its measurements of the weights of moving vehicles, ranging from lightweight vans to large cranes, deviated by only 0.5 to 3.0% from the known weights of these vehicles "We have standing still. As a result of a successful series of competitive developed evaluations by the Army Corps of the parallel Engineers, the Defense Nuclear Agency has provided funding for an virtual advanced system (for additional machine, a details, see sidebar on p. 26). network of As part of the research for DOE's proposed Heavy Water Reactor for computers the tritium-producing New throughout Production Reactor project at the Savannah River Site, ORNL's the country Engineering Technology Division that work was asked to determine whether the together on proposed primary piping for carrying Joe Wright adjusts the furnace of the Core Conduction the reactor coolant is safe. Cooldown Test Facility. It will be used to help researchers the same Specifically, we were asked to predict the fission product releases that would result during an complex accident involving the fuel of the proposed modular high­ demonstrate that the primary piping technical cannot break instantaneously and temperature gas-cooled reactor. cause a loss-of-coolant accident, problem, which has been considered a credible possibility. If of what used to be the Fernald Feed Materials doing the job research results show that such a double-ended Production Center in Ohio. The maps of the surface guillotine pipe break (DEGB) is not credible, the topology of the silos, obtained by computer-based of a super­ potential savings are considerable. The first stage of laser imaging techniques, were used to plan the computer." the research is now complete. A pipe was fabricated deposition of a 31-cm · to nuclear industry standards, and a flaw larger than (12-in.) bentonite clay cap over the silos to absorb any seen in piping in service in 60 years was the radon emitted by the stored uranium ore machined into it. ORNL's Pipe Impact Test Facility residue. Because accurate surface maps made was used to apply loads to the pipe 30 times at possible deposition of the bentonite only where it is levels equal to and greater than the impacts of a needed, excess placement of the material (and major earthquake. In addition, the pipe was put removal of it later) was minimized, saving the through some 200,000 fatigue cycles and two Fernald Environmental Management Project crack-tearing overloads to confum fracture approximately $25 million in remedial action costs mechanics theories and demonstrate that a DEGB is (for additional details, see Waste R&D sidebar on not possible. p. 87). An automated surface-mapping system ORNL's expertise in environmental impact developed by ORNL's Robotics and Process assessment has received international visibility. Systems Division as part of a DOE robotics project Scientists in the Environmental Sciences Division was successfully operated in the waste storage silos are assisting the Environmental Protection Agency

Number Two, 1992 17 STATE OF THE LABORATORY-1991: STRENGTHENING R&D

Bruce Poole, left, and Rick Battiste inspect ORNL's Pipe Impact Test Facility for the proposed Heavy Water Reactor for tritium production at the Savannah River Site. ORNL researchers used the facility to prove that an instantaneous break of the primary piping, which would lead to a loss-of­ coolant accident, was not a credible possibility.

in heading a United Nations Task Force on We have shown that a cold source for producing Applications of the Principles of Environmental very slow neutron beams from the Advanced Impact Assessment to Policies, Plans, and Neutron Source (ANS) is feasible. Using a Programs for the European Economic Community. scanning tunneling microscope, we have taken a ORNL also prepared an environmental impact picture of a complete gene-containing DNA statement for the National Science Foundation molecule. We have developed an automated system (NSF) to address the extent to which research for reloading ammunition in armored tanks and, as activities in Antarctica harm its pristine a result, the U.S. Army has cited ORNL as a world­ environment. We are also conducting other class research and development institution. assessments for the NSF to help improve management of the U.S. Antarctic Research Program to minimize its environmental effects. Outlook We have developed the parallel virtual machine, The proposed ANS, which we hope to build at a network of computers throughout the country ORNL by 1998, continues to be supported. This that work together on the same complex technical year the President's budget calls for $22 million to problem, doing the job of a supercomputer (see the support the design of and related R&D work on the sidebar on p. 24). ANS. This amount is less than we hoped for. We

18 Oak Ridge National Laboratory REVIEW are still working vigorously to persuade DOE to make the ANS a line item for fiscal year 1994. The Holifield Heavy Ion Research Facility, which had been identified as a candidate for closing by DOE, will be temporarily shut down for development of a radioactive ion beam capability. Its new ability to produce exotic beams will make it a unique facility for studies of astrophysical phenomena, providing a strong rationale for the accelerator's continued operation. We have been making plans for some time to relocate Barry Burks (left) of ORNL's Robotics and Process Systems Division and David Jacoboski and Dennis Nixon, both of the Westinghouse ORNL's Biology Environmental Management Company of Ohio, test the ORNL-developed Division from the Oak automated surface-mapping system. It is being used here for the Fernald Ridge Y-12 Plant to the Environmental Management Project to obtain accurate data on the contour west end of the X -1 0 of waste surfaces. Such information was used to plan the cost-effective site. Relocation requires deposition of bentonite clay caps over the surface of radon-emitting uranium a new building, called ore wasteforms. the Center for Biological Sciences, which would cost around $100 it is necessary to have a good proposal, but that it million. Because it takes a concerted effort to is never sufficient. What scientists and engineers persuade people in the government to make such a often don't see is the amount of competition commitment, we have made a new biology building involved in developing budgets. We probably at ORNL one of our higher-priority activities. This underappreciate the friendly bureaucrats in is one of the goals on which the R&D Strategic Washington who engage in the full contact sport Planning Committee will focus. It never works to of the budget battle-fighting for a budget and have as many as 20 "first-priority" activities. We getting it through the internal departmental must get behind and really push one or two projects process, fighting with the Office of Management that are at the top of the list. and Budget, and fighting with the Congress, which sometimes does-and sometimes doesn't­ help secure funding for programs of importance to Closing Observations ORNL. I would like to close with some observations that At times it seems that we at this end are a little may seem a little unusual. Over the years, I have contemptuous of their efforts and don't appreciate written and evaluated many proposals. I know that them. It doesn't hurt to say thanks to people who

Number Two, 1992 19 This ship is nearing the completion of its voyage to Antarctica, carrying ORNL researchers who have been assessing the environmental effects of the U.S. Antarctic Research Program. This computer­ generated drawing shows the reactor assembly for the proposed Advanced Neutron Source reactor.

The Holifield Heavy lon Research Facility has a new mission. It will reopen in 1994 with a radioactive ion beam capability that will contribute to astrophysics research.

21 STATE OF THE LABORATORY-1991: STRENGTHENING R&D

employees. But after our proposals are sent in, we do need them. It is important to keep that in mind. I am pleased that our relationship has improved with our DOE field office, and I think it is only fair to give Joe La Grone, Oak Ridge Field Office manager, a good deal of credit for that. I think I probably have a better understanding than most of field office problems because of my experience in the Department of Energy. The past year has not been easy for DOE field offices or the department. We need to show more understanding of their situation as we try to improve our situation in regard to doing research. I think that 1991 was a tough year for Clyde Hopkins, Energy Systems president. The Laboratory causes him problems from time to time. I do appreciate the fact that Trivelpiece congratulates Charlie Kuykendall, director of the he treats us with a good sense of Laboratory Protection Division, on the success of the division. It humor, and we appreciate his received a 1991 Director's Award for having been ORNL's best friendship and support in this, the service division. Trivelpiece recognized it "for addressing all Year of the Frog. activities effectively and efficiently, in a manner consistent with the Laboratory's values, and with a special emphasis on friendliness." Director's Awards Each year I give Director's A wards to outstanding divisions. In work in our behalf. I think that we have turned the 1991, I started giving one award to the best comer in our relationship with the DOE Oak service division and the other to the best research Ridge Field Office. Without their cooperation and division or program for the year. I will do the assistance, we wouldn't achieve some of the same this year. things we need to do. Now, relations are Because of the extra security required at ORNL sometimes strained, and there is a tendency to during the Persian Gulf War and other important point fingers at each other for things that should security activities, the group that deserves the have been done and weren't or shouldn't have most recognition is the Laboratory Protection been done and were. But I believe that most of the Division, headed by Charlie Kuykendall. The federal employees really want to do a good job, award citation recognizes this division "for and we should take that into account. Probably we addressing all activities effectively and efficiently, collectively suffer from a little hubris. I hope that in a manner consistent with the Laboratory's doesn't come as a shock. Sometimes we probably values, and with a special emphasis on believe we don't need the help of federal friendliness."

22 Oak Ridge National Laboratory REVIEW Roger Carlsmith, manager of ORNL's Conservation and Renewable Energy Program, received the 1991 Director's Award for the best research division.

The Director's Award for a research program conservation technology. The program includes goes to the Conservation and Renewable Energy research performed at DOE user facilities at Program, the largest program at ORNL. Funded at ORNL, especially the High Temperature $60 million, it is the largest conservation program Materials Laboratory and the Roof Research at any of the national laboratories. The person Center. The program was responsible for the first who built it as an outgrowth of an NSF program instances of technology transfer from ORNL that started at ORNL in 1970 is Roger Carlsmith. He used CRADAs. Industrial partners have conceived the idea for the program and obtained collaborated extensively with program researchers support for it over the years from the NSF, through subcontracting and joint efforts. The ERDA, and DOE. Its successes include the Conservation and Renewable Energy Program is development of high-efficiency heat pumps, high­ really a great model for a successful energy temperature superconductors, and advanced program. The award citation recognizes this materials for heat engines. Policy studies done by outstanding program for "its contribution to program participants have influenced electric increased energy efficiency and its responsiveness utilities and legislation dealing with the use of to industry's needs." IC!J

Number Two, 1992 23 Laboratory · Ltn ing Many Computers To Do 1991 a Supercomputer's Job

! anks to new computer PVM functions in a $250,000 has resulted in programs co-developed at computer network computing speeds rivaling ORNL, researchers something like a police those of $20 million throughout the world can officer directing traffic. The supercomputers. The use the combined power of software monitors the package has been used to "By using PVM to many desktop computers to informational traffic moving operate as many as 105 link many solve complex technical among the various workstations problems that once could computers in the network workstations simultaneously. "By using be addressed only by a and ensures that it flows as PVM to link many together, researchers supercomputer. The efficiently as possible. workstations together," get the best computer supercomputing capability PVM can increase the Geist says, "researchers performance for the is now available to cost effectiveness of get the best computer price." researchers through a research operations by performance for the price." software package called harnessing computer For those with the the parallel virtual machine workstations when their resources, PVM can also (PVM). users do not need them. be used to connect Created by a team from During off hours, several supercomputers. "It has ORNL, the University of workstations linked by PVM been used to link multiple Tennessee, and Emory can solve problems that supercomputers around the University, PVM is one of normally would be world to achieve the very the first software systems submitted to a more high computational to enable computers powerful mainframe performance needed to varying greatly in computer. In addition, the solve problems such as architecture and data software is publicly weather modeling and format to work together at available through an ORNL materials design," says the same time on a single electronic mail network. Geist. 'The amount of work computational task, such According to AI Geist, a achieved is limited only by as a complex calculation. co-developer of the the number and power of Linked together by a software and a researcher the computers accessed." network, these computers in the Engineering Physics PVM, which has been form a "virtual machine," a and Mathematics Division, dubbed the "poor man's configuration having the use of the PVM system to supercomputer," will be power of a multi-million- tap the aggregate power of particularly beneficial to dollar parallel super- workstations having a universities that have not computer. combined cost of roughly been able to offer courses

24 Oak Ridge National Laboratory REVIEW Heterogeneous Distributed Computing

in super­ the key to computing solving so-called because of the "computational high cost of the Grand hardware. "Thanks to Challenges," such PVM," Geist notes, as modeling the "students can now be global climate, taught how to write parallel groundwater programs that apply to transport of supercomputing, even "Individuals and The PVM package is hazardous waste, and the though their university businesses who have a small (requiring only 400 structure of super­ could never afford an need for this type of kilobytes of memory) and conductors. "At this time," actual supercomputer." In application and who have easy to install. A single Geist says, "these the fall of 1991, five access to an electronic installation on each problems can't be solved universities used PVM in mail network can also machine in a network by any one of the large this way. They were Emory obtain PVM through the provides accessibility to all serial computers because University, Florida State Laboratory," Geist said. To users, each of whom can they lack the power as a University, the University of obtain the PVM User's create his or her own virtual result of their physical Maine, the University of Guide and source code, supercomputer, which limitations. Thus, parallel Tennessee,andthe send e-mail to overlaps with other users' computers will be required University of Utah. [email protected] with this virtual supercomputers. to solve these problems." Use of the program is message: "send index from Parallel computing using -Wayne Scarbrough not limited to scientists. PVM." the PVM system may be

Number Two, 1992 25 Laboratory ORNL's Vehicle Weigh-in-Motion System: 1991 Things That Go Whump in The Night

W ump, whump! To the discriminating motorist this sound usually means one of two things-either Mr.

Possum zigged when he BEFORE DUR ING AFTER should have zagged, or one of those anonymous ' "Even though the traffic monitoring devices UNCOMPAESSEO COMPRESSED UNCOMPAESSED ORNL system was has counted another vehicle. Thanks to Jeff built from the ground TIME Muhs of ORNL's Applied up in nine months, it Technology Divison, we ~lllilliilll~~~~=-11111111111111 BEFORE COMPR ESSION outperformed the can add another potential SILICONE-RUBBER l competition in Army source of whumps in the OPTICAL FIBER ~-- lllllllllllllllillllilliii.IIIIIIIIB DURING COMP RESS ION Corps of Engineers road-the fiber-optic tests." weigh-in-motion (WIM) 'allllllllllllillllllilllllllllllll AFTER COMPRESSION system. The portable, lightweight The weigh-in-motion system uses an array of fiber-optic WIM system uses an array sensors mounted on the road to determine a vehicle's of fiber-optic sensors and weight. When a vehicle rolls across the system, it compresses the fibers, reducing the amount of light they contact switches mounted transmit. The greater the weight of the vehicle, the less light on the road to determine a is transmitted. vehicle's weight, speed, acceleration, number of axles, and several other one of the system's the vehicle, and data for all characteristics. transducers, it compresses wheels are summed to The system consists of optical fibers in the determine gross vehicle eight contact switches, two transducers, reducing the weight. In addition, each fiber-optic transducers (one amount of light they transducer is paired with a for each side of the transmit. The greater the set of four contact switches vehicle), an interface that weight of the vehicle, the that measure the time it converts optical signals to less light is transmitted. takes for the vehicle to pass electronic data, a battery The light that passes over the system, its lateral pack, and a computer through the compressed position in the roadway, and control system. When a fibers is translated into a other parameters to vehicle's tire rolls across weight for each wheel of determine other vehicle

26 produced readings accurate to within 3% of the known weight of the vehicles. Currently, the system is limited to vehicles moving at less than 16 kph (1 0 mph), but Muhs says he sees no practical limit to the system's speed range if money is available for further development. Several private companies have also expressed an interest in the WIM system for speeding up the process of weighing trucks on the highway and Members of ORNL's Applied Technology Division (shown here) developed a portable, assessing use fees for lightweight, accurate system for weighing vehicles in motion. The highly accurate system, vehicles hauling waste to which is based on fiber-optic technology, can provide weight measurements for moving landfills. vehicles (ranging from lightweight vans to large cranes) that deviate by only 3% from the known weights of static vehicles. Muhs sees applications for the WIM systems in the traffic control systems of the near future. "The system characteristics, such as developed by the Texas monitoring traffic moving in could be used to assess tolls speed and acceleration. Transportation Institute. and out of military on vehicles without requiring To convince potential Even though the ORNL installations and regulating them to stop," says Muhs. "It sponsors of the system's system was built from the the loading of ships and would also provide a more capabilities, Muhs and his ground up in nine months, transport planes. The WIM equitable assessment of colleagues took the system it outperformed the has also been proposed as tolls, based on vehicle to an Army Corps of competition. As a result, a method of ensuring weight." Other potential uses Engineers test facility in further d&velopment is now proper weight distribution in include characterizing traffic Vicksburg, Mississippi, for being funded by the aircraft taxiing for takeoff. by speed or type of vehicle a head-to-head competition Department of Defense, In tests with loads or detecting commercial with an established which is interested in the ranging from a light van to truck traffic trying to avoid piezoelectric system . WIM as a method of a 60-ton crane, the system weigh stations.-Jim Pearce

27 n Eye on Reactor and Computer Control

By Jack Schryver and Bill Knee

nuclear power plant operator stared computers. Other applications include controlling at the computer screen and yawned. camera positions on robots and guiding an A As the end of a long shift artificial intelligence system in recognizing approached, he was feeling very tired as he enemy targets. looked at icons of pumps, pipes, and turbines. At ORNL computer software has been Even so, it was still early in the reactor startup developed to make possible an improved eye­ sequence. When an indication that the reactor had gaze measurement technology. Such an gone critical appeared on the screen, the operator innovation could be the basis for advanced eye­ tried to rouse himself. There was no need for him gaze systems that may have applications such as or anyone else to be alarmed, however. Based on those mentioned above. the way the operator looked at the screen, the Eye-gaze computer had already sensed that he was tiring The Problem of measurement and had begun to assist the operator in reactor Reactor Control technology control. The computer zoomed in on the displays the operator needed to monitor reactivity and The nuclear power plant, like many other improved by highlighted the important data. It would even be process control environments, is an extremely ORNL capable of assuming partial reactor control if complex system. Control rooms of conventional necessary. nuclear power plants reflect the complexity of the software may At a research laboratory, a cognitive scientist systems they control. Visitors are usually have put a diskette in her computer and studied the overwhelmed by the hundreds of meters, gauges, fascinating screen. The data indicated that a reactor operator and switches that are arranged on vast control had been glancing at a number of widely scattered panels. Even a trained operator fmds it difficult to uses. points in a short time on the computer screen in be totally aware of all the information available in the reactor control room. "All these eye the control room and to make decisions about movements," said the scientist, "tell me the plant operation under time pressure. Thus, it is operator is experiencing excessive mental work not surprising that human error in the control of load. It seems that several displays associated nuclear power plants is often implicated in with reactor control must be redesigned to make it incident reports concerning a compromise of easier for the operator to understand quickly plant safety or unnecessary plant shutdown. what's going on." The physical functions of the nuclear power A teenager who lost the use of both hands as a plant are relatively well understood by designers. result of an automobile accident had found a way However, little is understood about mental tasks to write again. His father bought him an "eye performed by operators and the associated types typewriter"-a computer that displays and prints of cognitive error. Furthermore, little is known letters from a display of the alphabet on the screen about the types of information actually required in the order in which they are stared at. The boy to perform these cognitive operations and about enjoyed his ability to control a computer simply the form in which they should be represented to by looking at it. support the operator's mental model of the plant. These ·futuristic scenarios suggest that A central concern is how to provide critical information on eye gazes-the way people look at cognitive support to the operator to ease the an object-can be put to use to determine a effects of excessive mental work load, which can person's mental work load and level of fatigue, to lead to human error. These concerns are also guide the design of computer displays to speed important for other complex human-machine human processing of information, and to control systems, including teleoperated systems,

28 Oak Ridge National Laboratory REVIEW chemical processing plants, spacecraft, airplanes, question after the display was removed, they still and other transportation vehicles. One approach to fixated on the same position in space where the reducing operator error is the use of advanced drawing of the car had been located. These results eye-gaze measurement technology. suggest that eye fixations play an important organizational or place-keeping role in cognition. A Window to In ORNL's Engineering Physics and Mathematics Division, the Cognitive Systems and the Mind Human Factors Group is now using eye-gaze data It has been said that you can sometimes tell to increase our understanding of how operators what a person is thinking "by the look in his eye." view and use data shown in information displays The look, or eye gaze, can be measured by an for complex systems. Eye-gaze data are enabling eyetracker, an unobtrusive device that can us to gain a better understanding of how determine the spot on a computer monitor at which a person is looking. Eyetrackers can measure eye-gaze direction 30 times per second. Cognitive psychologists have been using eye-gaze measurement methods for over 15 years to capture "direct" snapshots of mental processes, including how people read. According to the "eye-mind hypothesis," the eye fixates on the symbols currently being processed by the brain. Several experiments have demonstrated that the eye can be a window to the mind. In a typical experiment, human subjects were shown a small array of simple drawings of common objects. When the Jack Schryver works with the Eyegaze™ Development System, which subjects were asked, "What consists of a standard VGA color monitor (upper left), eye-image television monitor (lower left), personal computer with frame-grabber makes of car can you board (not shown), and an infrared-sensitive CCTV camera with an name?", they tended to look infrared light-emitting-diode source positioned over the camera lens. The at the drawing of a car camera is mounted under a Sun Workstation. A serial port connection while responding. permits tracking of the eye movements of a user at the workstation as Furthermore, if the subjects well as storage of eye-gaze data on disks for future analysis. were asked the same Photographs in this article by Tom Cerniglia

Number Two, 1992 29 AN EYE ON REACTOR AND COMPUTER CONTROL

reports are biased toward the expectations of the questioner, or what the respondent believes are questioner expectations. Answers often conform to textbook statements of written procedures. Verbal explanations usually reveal the tip of the iceberg, but a vast store of tacit knowledge often remains hidden during the fast pace of events. On the other hand, eye-gaze data are quantitative and can be treated as any other quantitative data. The scan path the eye traces over a display is objective and unbiased. Finally, eye movements can occur rapidly and keep pace with high-speed cognitive processes.

The Eye-gaze System Eyetracking technology has undergone a slow evolution over the past 20 years. The new eye­ The eye-image monitor shows the human eye as it gaze system marketed by LC Technologies of scans a stimulus display. The eye-gaze system Fairfax, Virginia, offers state-of-the-art grabs 30 frames per second for image processing eyetracking. Most of the hardware is off the shelf. and computes eye-gaze direction based on the Eyetracking is done with a standard personal "When the relationship between pupil center and corneal glint. computer equipped with a video frame-grabber human eye is board. An infrared-sensitive high-speed camera is focused in mounted under a standard high-resolution the camera information should be presented so that it can be computer screen. A small light-emitting diode easily understood and used. (LED) is positioned at the center of the 75-mm lens, infrared Curiously, the operator is the only control camera lens. light from element in the plant whose behavior cannot be When the human eye is focused in the camera described in terms of a known set of equations, lens, infrared light from the LED is reflected off the LED is because little is known about the cognitive the eye. A simple algorithm takes advantage of reflected off activity of operators. Because the cognitive two optical phenomena resulting from infrared the eye." activity of the brain cannot be observed directly, illumination. One of these effects is the bright-eye little attempt was made for many years to effect, an illumination of the pupil similar to the understand what operators were actually thinking red-eye effect that photographers try to avoid. The while controlling the plant. System designers other is a bright spot created on the surface of the most likely assumed that a plant could be operated cornea, known as corneal glint. lf the vector safely and efficiently if operators were trained to relationship between the pupil center and corneal follow procedures and that, consequently, it was glint can be determined, then the direction of the not necessary to understand the mental processes eye gaze can be calculated. Furthermore, if of the operator. someone is calibrated to a particular display An obvious alternative approach in the study of screen (a simple procedure involving fixating on a cognitive behavior is to ask operators what they series of circles presented on the screen), then the are thinking and use their answers to suggest ways point being looked at can also be calculated. to better support cognitive tasks. Verbal protocol This simple method of determining eye gaze analysis techniques have been used with some was discovered by Tom Hutchinson of the success, but they suffer from several weaknesses. University of Virginia in the early 1980s, and it Psychological research has shown that verbal was licensed for commercial production to LC

30 Oak Ridge National Laboratory REVIEW Technologies in 1988. LC Technologies number of line segments visible in the drawing is developed some very efficient image-processing also user-selectable to avoid excessive clutter on software to locate the pupil center and corneal the monitor for long protocols. When the trace glint in real time. Tills software is able to reaches the maximum length, old gazepoints and discriminate these phenomena from extraneous line segments are erased and replaced by new effects, such as reflections from spectacles and gazepoints and segments. other bright spots on the eyeball surface. Using the trace playback tool, the analyst may test a new graphical user interface and Application Software immediately view the trace laid over the screen. It is possible to see successive fixations at the Developed at ORNL desired speed and correlate the trace with At ORNL we have developed application meaningful objects in the underlying display. This software for the eye-gaze system to fulfill two tool can help the analyst build intuitions about broad purposes. First, we want to provide the connections between eye-gaze activity and researcher with a visualization tool to immediately graphical user interfaces. It is also useful for show the scan path taken by the operator's eyes quickly evaluating displays for human factors while inspecting a display screen "for process engineering. control. The trace playback software displays the Second, we are also building a library of graphical interface, and a drawing of connected quantitative tools for analysis of eye-gaze line segments is overlaid on the monitor. Each protocols. The data analysis tools use an output new point in the connected line drawing file containing records of successive gazepoints represents a new gaze point in the protocol. collected while the operator inspects a graphical Playback speed is user-selectable and the user-interface. These tools can be used off-line to playback may be paused at any point. The total analyze multiple data sets. We have identified at

A simplistic operator interface to a fictitious nuclear A playback over the operator interface of the scan power plant. The operator scans the data displays path of the eyes of a user performing a validation while performing a task such as diagnosis or task. prediction.

Number Two, 1992 31 AN EYE ON REACTOR AND COMPUTER CONTROL

least three layers in eye-gaze protocols to reduce determine whether the complexity of transitions the large number of data that must be analyzed. among several areas of interest, based on eye­ The gaze point-the spot on the screen where the fixation data, is related to the mental work load of user is looking-is the lowest level of data; it is inspecting a graphical user interface. sampled at a rate of 30 Hz by the eye-gaze system. At this rate of sampling, 1800 gaze points Cognitive Engineering will be determined for every minute of data Experiments Planned collection. An intermediate level of analysis is the We are preparing to conduct cognitive "The eye fixation-a sequence of gaze points within a engineering experiments using a UNIX scan path small area that occurs over a short time. Eye workstation at ORNL. We selected a UNIX fixations are closely related to detailed visual platform to separate the development platform reveals the processing of objects in the scene, and they occur from the eye-gaze system. The goal of much of order in in the foveal or central region. Virtually every our development work on the UNIX workstation object is recognized when the eye fixates on it, has been to create experimental tasks for which which the and not while the eye is engaged in rapid, or eye-gaze data can be captured. In addition, we pilot fixates saccadic, movement. The fixation lasts from want to store keyboard strokes and mouse clicks on the 200 ms to several seconds. Even while the eye is to correlate with eye-gaze protocols. Some of our fixated, gaze-point activity is characterized by original graphical user-interfaces were created instruments." slight jitters and perhaps some drift. New using the X Window System on the UNIX fixations are characterized by sudden movement. platform to ensure portability of the software. At ORNL we have developed a fixation post­ Controlled experiments are needed to processing routine to analyze raw data on gaze standardize procedures for collecting eye-gaze points and identify the location and duration of protocols. In the standard experimental setup, a fixations. This procedure reduces the number of volunteer is seated at the workstation and an data by up to an order of magnitude. infrared-sensitive camera, calibrated to the The highest level of analysis is the area of monitor, is mounted underneath. A series of interest, which corresponds to a meaningful graphical user interfaces to various human­ region in the graphical user interface. For machine systems are presented to the volunteer example, if the display shows a plant schematic, subject, who is charged with a specific task or the area of interest might correspond to a region responsibility. In a prediction task, for example, containing drawings of valves, pumps, or turbines each volunteer is shown initial conditions of a as well as connections such as pipes. Eye-fixation transient event, such as loss of a primary pump, protocols can be analyzed to determine how much and a candidate outcome state, such as elevation scan time is given to each area of interest. This of coolant temperature, is displayed in another measure indicates the relative depth of cognitive window. The subject's task is to verify the processing given each area on the display. plausibility of the outcome state. We can also study the transfer of attention from A related task is diagnosis. Each volunteer is one area of interest to another by assembling an shown an outcome state and is asked to choose area-of-interest transition matrix. This matrix among alternative initiating events that could lead shows the number of fixations between each area­ to this state. In this example, to get the right of-interest pair, indicating that the user is answer, the subject must select "loss of power to combining information from several areas of pump" instead of "turbine trip" or "feed water interest before making a decision. The complexity valve fails to open." In fault detection, a normal of the scan path is reflected in the number of transient is depicted. The subject monitors the successive fixations between areas of interest as transient and is asked to respond appropriately to compared with the number of successive fixations the fault when it is detected. In this example, the within areas of interest. We are trying to subject first notices the temperature change or

32 Oak Ridge National Laboratory REVIEW pump coastdown. For implausibility detection a ought to minimize opportunities for cognitive subject views a display showing dynamic data error. from a simulated system and attempts to determine the validity of the data. Prediction of Mental Work Load Evaluation of Displays The complexity of control rooms of Scan path traces from early eyetracking conventional nuclear power plants is well­ instruments in human-machine systems were first documented. The need to integrate diverse used to analyze the arrangement of displays. The information simultaneously can produce periods "We believe aviation industry used eyetracking in the cockpit of peak overload for the operator. Therefore, it is that eye-gaze because each pilot is faced with a cluttered important to be able to predict those situations arrangement of displays on an instrument panel. that may result in excessive mental work load for data reflect When monitoring the status of the aircraft, the individual operators. During the onset of an not only the pilot views the displays in a relatively fixed accident such as loss of coolant, the operator degree of order. If the pilot is required to repeatedly scan would be inundated by a large number of alarms back and forth across the panel to locate and read and annunciators. Identifying the relevant alarms effectiveness instruments, monitoring becomes quite is a difficult pattern-recognition problem that may of interfaces cumbersome. This situation will be reflected in induce high work load and stress. an extended and convoluted scan path. The eye Indications of mental work load can be found in but also task scan path reveals the order in which the pilot eye-gaze protocols as operators extract complexity." fixates on the instruments. From this information from displays showing relevant data information, instruments that are fixated on in about plant status. Psychologists have long known succession can be grouped to simplify scan paths that pupil diameter is related to cognitive arousal during monitoring. or the need for information, and hence, the degree Scan paths can reveal more than the best way of mental work load. Scan path complexity is to arrange instrument displays. The eye-mind another estimator of mental work load. We have hypothesis suggests that stages of an operator's performed pilot testing with problems in mental cognitive processing can be inferred while this multiplication of numbers. Our results indicate individual inspects graphical user interfaces. The that difficult problems tend to generate longer and actual stages of processing inferred from the data more complex scan paths. We believe that eye­ can then be compared with an ideal cognitive gaze data reflect not only the degree of model to determine how actual processing effectiveness of interfaces but also task departs from the intended use of the display. This complexity. comparison provides the analyst with a powerful A correlation may exist between mental work basis upon which to evaluate the effectiveness of load and scanning strategies employed for advanced interface concepts. different tasks. We suspect that low-work-load In addition, types of cognitive error and their activity such as passive monitoring leaves a frequency will be observable in eye-gaze distinct eye-gaze signature. Eye movements protocols. Such errors may include reading a during passive monitoring are referred to as open­ display incorrectly, forgetting to perform an loop scanning; the next fixation does not depend action, and reaching the wrong conclusion. on the information content of the present fixation. Models of cognitive error during inspection of Displays may be scanned according to a simple operator interfaces offer a powerful new predetermined sequence. On the other hand, fault dimension of evaluation. Eye-gaze protocols diagnosis is probably characterized by closed­ both suggest and validate sources of cognitive loop scanning, in which the location of the next error. We believe that "natural" interfaces that fixation is not determined until cognitive conform to the mental model of the operator processing of the present fixation is completed. If

Number Two, 1992 33 AN EYE ON REACTOR AND COMPUTER CONTROL

this hypothesis is true, closed-loop scanning of the monitor. A special "key" is used to delete should be detectable in the correlations between mistaken picks. One problem with eye input is eye fixations and the information content of the so-called "Midas touch" situation. When the displays. user is searching an area for a particular letter, As suggested in the introduction, a possible many false positives can be created: such items future appucation of eye-gaze measurement are evaluated and then rejected. The incidence of technology is determining when reactor operators false positives can be lowered by increasing the are too fatigued to do their jobs effectively. In dwell threshold for selection, but the trade-off for such cases, detection of excessive mental work increased accuracy is decreased processing speed. load by a computer could activate it to assist the Teleoperated vehicles and robots that have "The human operator in reactor control. many degrees of freedom that may be manually Intelligent interfaces could guide the operator's controlled may benefit from eye input. For eye may also attention to relevant displays by highlighting, example, a legged vehicle under manual control be used to blinking, or zooming in on the appropriate while climbing stairs may require both hands of control a information. Real-time expert systems could the teleoperator to control leg motions. Eye input present the operator with an estimate of current could be used to control additional degrees of computer." plant status together with an explanation of what freedom, such as video camera position. happened. Many other kinds of cognitive We are now engaged in a proof-of-principle assistance are possible under conditions of peak project that will demonstrate eye-gaze control of work load. the perspective view of a 3-D interactive graphical interface. The new interface is "natural" Telerobotics and because object rotation responds to the user's Human-in-the-Loop active search for information. When the user shifts the eyes to ee hidden parts around the edge Target Recognition of an object such as an airplane or robot arm, it The human eye may also be used to control a automatically rotates toward the user and reveals computer. In this case, eye-gaze measurements the areas of interest. can be entered into the computer as a substitute Data on human eye gazes may also enhance for keystrokes and mouse clicks. An individual computer vision, one of the most difficult facing a graphical user interface can issue a problem areas in robotics and automatic target specific command to the computer merely by recognition (ATR). ATR systems have not looking at a specific region on the monitor. achieved the reliability and robustness required Controlling a computer by looking at it promotes for this difficult task. The human visual system is a feeling of power in the user. It is almost as if the highly advanced and able to use the parallel user commands the computer directly with the architecture of the brain to perform visual tasks mind. The interface, if properly designed, can unequaled by computer systems. Human-assisted become so natural that the user forgets it is ATR may be able to improve the performance of present, leaving the impression of mind control. such systems. LC Technologies has produced several For example, if a simplistic ATR computer is impressive appucations for the disabled. One of asked to search for enemy tanks, it may scan the the most useful programs is an eye typewriter. A entire scene, including the sky, for such objects. graphical keyboard is presented to the user who A human would look at the ground, not the sky, types by focusing, or "dwelling," on the region for such targets. In human-assisted ATR, real­ containing the next letter of text to be generated. time eye-gaze data taken as a person surveys the When dwell time exceeds the user-selected scene would be used to guide the ATR in threshold, the letter appears in the text at the top identifying regions of that scene where targets

34 Oak Ridge National Laboratory REVIEW most likely will be located. As a result, computing time is saved because the A TR can avoid scanning regions not considered likely to have potential targets.

Future Directions for Eye-gaze Systems A limiting feature of the eye-gaze system is intolerance to head motion. The head must be kept stationary within a tight volume to keep the eye focused in the center of the camera lens. It is possible to mount a camera on specially constructed headgear to ensure that the eye is always in focus. But this sort of gear is obtrusive and can provide eye-gaze direction relative only to the head. It is difficult to correlate the eye-gaze data to the spatial coordinates of a display. Some Biographical Sketches systems have a headtracker that allows the camera to follow the eye as the head moves through a Jack C. Schryver is a research staff larger volume of space. The camera remains fixed member of the Cognitive Systems and in its mounted position, but a motorized rotating Human Factors Group in the Intelligent mirror and motorized focus ring track the eye to Systems Section of ORNL's Engineering keep it in focus. Image processing, ultrasound, Physics and Mathematics Division. He and a second camera can all be used to predict the has a B. A. degree from the University of direction of head movement to control the California at Los Angeles and a Ph.D. motorized mirror. Such systems are in various degree in cognitive and experimental stages of development, but none, as yet, are very psychology from the University of reliable. California at Irvine. His research interests The headtracker described above operates in an include experimental cognitive science, environment comparable to the volume occupied cognitive modeling, simulation, and by a user seated before a workstation monitor. human-computer interaction and Future eye-gaze systems will be able to perform visualization. unobtrusive computation of head position and Helmut E. (BiD) Knee is leader of the eye-gaze direction in a small control room. Cognitive Systems and Human Factors Because future systems will simultaneously Group. He has an M.S. degree in nuclear calibrate several displays, it will then be possible engineering from UCLA and an M.S. to collect eye-gaze data from an entire control degree in business administration from room crew while using multiple displays to the University of Tennessee. His research control a complex system. As eye-gaze systems interests include human performance and evolve from the laboratory to real-life situations, visualization in complex control they will become valuable tools for understanding environments, human and system human-machine systems, improving reliability, and behavioral and cognitive communication of information, and easing the modeling. mental work loads of operators of process systems, including nuclear power plants. 1:!]

Number Two, 1992 35

mountain stream, a beating heart, a irregular phenomena. These summarize empirical smallpox epidemic, and a column experience-that is, measured data- in some A of rising smoke are all examples of convenient form , usually guided by general dynamic phenomena that sometimes seem to physical constraints or relationships. In cases behave randomly. In actuality, such processes where only gross or average behavior patterns are exhibit a special order that scientists and important, these descriptions have often been engineers are only just beginning to understand. useful. The development of aircraft design This special order is "deterministic chaos," or correlations from wind tunnel measurements is a chaos, for short. good example of empirical engineering. Today chaos theory is employed to monitor and Unfortunately, empirical engineering can be control the interaction between particulates and costly and inefficient. Numerous trial-and-error gases in the turbulent flow of a fluidized bed, thus experiments must be performed to generate improving its performance and reducing correlations relevant to situations of interest. emissions of gaseous pollutants. In the future Correlations are also only valid for the parameter chaos theory may be used to smooth airplane ranges tested; extrapolation to untested situations flight and reduce fuel consumption. Heart is risky at best. pacemakers may someday be tuned to issue More recently, engineers have attempted to go ORNL is warnings when they detect undesirable heartbeat beyond empiricism by developing computer applying patterns that signal a heart attack days or weeks models that simulate physical laws and details to away. a high degree of precision. This approach has chaos As a researcher in ORNL's Engineering been made possible by the increasing availability theory to Technology Division, I am particularly interested of high-speed, large-memory computers. in applying the new discipline of chaos theory to Although successful in some cases, such engmeerzng engineeri ng. Chaos theory seems to be especially "number-crunching" approaches are often costly problems suited fo r dealing with a major difficulty that has and complicated, may contain many untestable such as puzzled engineers for centuries: how to describe assumptions, and frequently yield Little processes that are governed by explicit laws of improvement in fundamental understanding. fluidized cause and effect but seem to behave almost Another important problem with detailed beds. randomly in practice. computer models is that they are sometimes Turbulent fl uid flow, as in fl uidized beds used "linearized" to make them more tractable. In in industry, is a good example of such an unruly other words, all physical influences are assumed process. Even though the governing physical laws to be directly additive; that is, if a given are known, under many conditions-such as in a magnitude of cause A produces X units of effect mountain stream or near the wi ng of an airplane­ B, then twice the previous magnitude of A the mathematics of fl uid flow becomes extremely produces 2X units of B. Nonlinear relationships complicated, and the actual behavior becomes so are not so straightforward. For example, doubling erratic that making detailed predictions is A might cause B to increase fourfold. We now impossible. Attempts to understand this problem know that nonlinearities are often essential to the have prompted some of the deepest questions in behavior of many systems and that their removal modem physics. can completely change the resulting dynamics. To make at least some headway in practical Chaos theory offers a new approach for situations, engineers have traditionally relied on explaining and dealing with complicated statistical descriptions or "correlations" of behavior. As more engineering problems are

Stuart Daw (left) and Ke Nguyen of the University of Tennessee examine a fl uidized-bed column whose pressure differences are displayed on the oscilloscope (see photo on p. 45). The researchers are studying chaotic fluctuations in fluidized-bed pressures.

Number Two, 1992 37 SEEKING ORDER IN CHAOS

considered in light of this theory, it is becoming known as sensitivity to initial conditions. This is a increasingly apparent that irregularity is often a technical form of the more common notion that key to understanding the fundamental nature of sometimes even very slight changes in starting dynamic systems. Apparent randomness can result conditions can result in drastic changes to the final not just from unknown physical parameters, outcome. A familiar example of this notion is the measurement error, and outside noise, but also saying: "For want of a nail the shoe was lost, for from simple, nonlinear deterministic components. want of a shoe the horse was lost, for want of a "The word In fact, many systems appear to be dominated by horse the rider was lost, for want of a rider the deterministic randomness. chaos was battle was lost," and so on. When dynamic systems exhibit sensitivity to coined by Chaos vs Randomness initial conditions, our ability to predict what will happen next decreases exponentially over time. early Deterministic chaos should not be confused Even if we know the deterministic law relating the with the common notion of total disorder. In a investigators states at time t and time t+ 1, we will never be able sense, deterministic chaos is the opposite of to know the starting state at time t with infinite because the disorder because it actually refers to highly precision. We may be able to predict the next state structure can structured behavior. The word chaos was coined with acceptable accuracy, but as we extrapolate by early investigators because the structure can be be invisible to farther into the future, the effect of the initial invisible to the casual observer, thus giving the uncertainty grows so rapidly that it soon dominates the casual impression of randomness. our result. Before long we have no hope of making As the adjective deterministic implies, this type observer, thus an accurate prediction. To a casual observer it can of chaos arises in physical processes or systems appear that the system is being perturbed by some giving the that follow explicit rules of cause and effect. random influence. impression of Thus, in practice we can model the current state of The most common cause of sensitivity to initial a deterministic system as a unique function of its randomness." conditions is the presence of nonlinearities in the previous state. Typically, the relationship between governing relationship between sequential states in past and future is expressed in terms of finite time. As described previously, nonlinearities are difference or differential equations. characterized by nonproportional changes in the The motion of a satellite around the earth is a result for a given change in input. For example, the familiar deterministic system. Given an initial equation y = :i2 is a nonlinear relationship between satellite position and velocity, the laws of x andy. Doubling x quadruples y. The equation Newtonian mechanics make possible construction y = 2x , on the other hand, is linear. The first of a model that unambiguously predicts the equation can be linearized by assuming that, for satellite's position and velocity at the next cases of interest, x is nearly constant at some value moment. By contrast, in processes such as the k and rewriting the relationship as y = kx. In effect, decay of an atomic nucleus or the motion of an this change forces the equation to be linear. The electron in an atom, the governing laws of importance of nonlinearities was almost completely quantum physics allow predictions only of the unrecognized by the scientific and engineering probabilities of succeeding states. In these latter communities until within the past two years or so. cases an unambiguous relationship no longer Before that time nonlinearities were basically exists between conditions at one instant in time ignored because they were mathematically and the next. "messy." Most models that contained nonlinearities What Causes Chaos? were linearized so that they could be solved in analytical form. At first glance, the idea that irregularity can With the advent of modem computers, it became arise from deterministic behavior would seem to possible to observe the results of nonlinearities be a contradiction. In mathematical terms, directly without the need to resort to analytical deterministic irregularity is related to a property solutions. As a result, a few key researchers

38 Oak Ridge National Laboratory REVIEW quickly began to realize that science had been systematically excluding 30 .------~------. (albeit unknowingly) a major reality in CASE 1 : X(0)=.0598574 the behavior of the natural world. 20 Surprisingly, this realization has been slow to take hold in the technical 10 community as a whole. Scientists and engineers still have a strong tendency X 0 to linearize models, even though they may be solving those models using a "Anyone -10 computer. We are still strongly who has influenced by a legacy of linear -20 thinking. CASE 2 : X(0)=.0598600 driven on a

-30 +------.------.------.------,------1 hot desert Chaotic Structure 0 2 3 5 road during TIME (S) in Thermal Convection the day has To better understand how the seen the inherent order in chaos can be Two time series plots of flow from the Lorenz model of visualized, it is helpful to consider thermal convection illustrating the rapid divergence in dancing another simple example. Anyone who behavior resulting from slight changes in the initial condition. mzrages has driven on a hot desert road during produced by the day has seen the dancing mirages produced by the air as it rises from the heated We could be content to just observe the the air as it surface. The motion of the air in this case is a variation of flow and temperature patterns rises from form of natural thermal convection, induced by individually over time, but a much more useful the air's lowered density as it warms near the approach is to plot the flow and temperature the heated road. This same basic process produces the variables against each other as in the figure on surface." thermals exploited by birds and hang glider pilots. p. 40. Recall that X represents flow; Y and Z A simplified mathematical model of this process represent horizontal and vertical temperature was developed about 30 years ago by Professor variations. At each moment in time, the Lorenz Edward Lorenz of the Massachusetts Institute of model produces values for X, Y, and Z that Technology. Mathematically, the model consists represent a complete description of the of three ordinary differential equations that dynamical state of the convecting air layer. describe how the global patterns of air flow and When continously plotted, the XYZ combinations temperature change over time. Nonlinearities are produce a "map," or "trajectory," of the patterns prominent in two of the equations. produced over time. Such plots are termed state­ Integrating the model over time produces a space or phase-space trajectories. simulation of the patterns that would be observed As we see in the figure on p. 40, the XYZ in the layer of air. The figure on this page is a patterns produced by the Lorenz model vary depiction of the Lorenz variable representing the continually over time, never settling down to a air flow (designated by convention as X) plotted single point and never exactly repeating. against time. The figures show two different Nevertheless, over relatively long periods of traces, each representing the behavior that would time the Lorenz phase-space trajectory begins to occur for slightly different starting conditions. fill in a distinctive shape called the attractor. Note the rapid divergence in similarity between Magnifying this structure reveals an endless the two traces after an initial period during which level of repeating detail that can be described in they remain close together. terms of a new mathematical tool called fractal

Number Two, 1992 39 SEEKING ORDER IN CHAOS

Chaotic Time

80 Series Analysis About three years ago I began collaborating with three other ORNL colleagues in applying chaos theory to z engineering systems. Our principal interests were (and still are) to determine if particular systems are, in fact, deterministically chaotic, to visualize and quantify the chaotic

10 patterns if they exist, and to use the resulting information in practical ways such as improved design and control. "Fourier After considering various approaches, we decided that the best approach analysis is 30 clearly would be to focus on the analysis of time series measurements. appropriate Time series measurements are when the Graphical representation of the simultaneous variations in flow sequential records of physical (X), horizontal temperature gradient (Y), and vertical variables such as velocity, governing temperature gradient (Z) produced by the Lorenz model of temperature, or pressure that are relationships thermal convection. Deterministic chaos causes these collected for some period of time from and resulting variables to oscillate in a pattern that never exactly repeats. a process or system. Typically, such mea urements are depicted graphically patterns are as time traces like the Lorenz X linear, but it geometry. Fractal geometry is a universal variable in the figure on p. 39. Other familiar characteristic of chaotic proces es involving examples of such data are stock price , is inadequate friction, which are of primary interest to temperature and rainfall records, and the speed of when the engineers. Nonchaotic systems al so have a car's engine. attractors, but their attractors are not fractals. data being The analysis of nonchaotic time series is highly To distinguish chaotic attractors from developed and relatively routine. One common analyzed are ordinary ones, the former are called strange technique used by engineers is Fourier analysis, a chaotic." attractors. Attractors provide a unique way of mathematical procedure that models variations defining and comparing the structure of over time as combinations of sine waves (that is, different chaotic processes. In effect, it is regular waves of constant amplitude and possible to use the attractor as a kind of frequency). Fourier analysis is clearly appropriate dynamic "fingerprint." Not only do attractors when the governing relationships and resulting allow us to more conveniently picture the patterns are linear, but it is inadequate when the underlying patterns, they can be mathematically data being analyzed are chaotic. analyzed to obtain numerical descriptions. Even In evaluating chaotic time series measurements slight changes in the chaotic behavior (when the from engineering systems, we have found that the system parameters, operating conditions, or most productive approach is to construct phase­ inputs are changed, for example) are readily space trajectories analogous to those shown in the detectable as changes in the attractor figure on the opposite page. Because it is usually characteristics. Much of chaos theory focuses not possible to measure all of the dynamic on the proper methods for visualizing and variables in a system, trajectories mu t typically describing attractors. be constructed from a small set of selected time

40 Oak Ridge National Laboratory REVIEW series measurements. Construction is accomplished using a mathematical technique called embedding. The embedding technique is, in fact, so powerful that it is theoretically possible to construct a representation of the :, ~ ~\ r1 tv\llfit behavior of all of the dynamical t ----'? variables of a system from measurements of a single variable. TIME DOMAIN Thus, for example, it is possible to reconstruct the contributions of Y and Z in the Lorenz model (and thus a dynamically equivalent facsimile of the figure at left) from measurements of the X variable alone! l The final result of the embedding X2 procedure is a transformation of the original time series data into a reconstructed phase-space trajectory as shown in the figure at right. Once this reconstruction has been accomplished, Xl the resulting patterns can be analyzed in X3 detail to determine whether or not the system is chaotic, linear, or purely random. If it is chaotic, the distinctive measures of the attractor can be used to PHASE SPACE uniquely define the underlying structure and compare it to other systems, conditions, or models. To analyze chaotic time series, the original data are Dynamical systems often have more transformed into a "reconstructed" phase space. The phase­ than three important components, and space reconstruction represents a kind of "fingerprint" of the the resulting phase-space can be dynamical patterns in the data. difficult to visualize directly becau~e it requires more than the three dimensions solids and fluids (either liquids or gases). Briefly, encountered in everyday experience. One approach they consist of vertical chambers containing to this problem is to make projections of the "beds" of solids through which fluid flows trajectory in two or three dimensions. upward. The fluid flow is sufficiently high to Mathematically, however, the analytical procedures suspend the solids, which swirl about the chamber are identical, and no serious problems occur in in turbulent patterns reminiscent of thermal making quantitative descriptions of trajectories in convection. Commercially important processes more than three dimensions. using fluidized beds include refining petroleum and minerals and fluidized combustion of waste Specific Applications and high-sulfur coal. The turbulent flow of fluid and solids in We initially selected fluidized beds as a trial fluidized beds is one of the most desirable engineering system for applying chaotic time series characteristics for mixing, but it is also the source analysis. Fluidized beds are widely used in industry of much complexity and engineering uncertainty. to promote intimate mixing between particulate Although fluidized beds have been prominent in

Number Two, 1992 41 SEEKING ORDER IN CHAOS

the chemical and petroleum industries

Dimensionless velocity = l1 for several decades, their design and control is still largely empirical. It is still common to fmd large multimillion­ dollar facilities initially constructed for specific performance specifications (such as yield of a particular chemical product or degree of sulfur removal) only to discover after startup that expensive testing and trial-and-error equipment modifications must be made ~+------~ to meet the original design goals. -5 10 Our approach in applying chaos Principal Component 1 theory to fluidized beds has been to analyze the experimental chaotic time Dimensionless velocity = 4.9 series of pressure and voidage measurements taken from several different test facilities here and at other collaborating DOE laboratories and universities. From past experience we know that pressure and voidage fluctuations are good indicators of the fluidization state. The results to date clearly demonstrate the presence of deterministic chaos and suggest the -5+------~ -5 10 possible ranges of chaotic behavior that Principal Component 1 can be expected in commercial fluidized beds. The figure at left illustrates three examples of chaotic attractors constructed from fluidized-bed pressure Dimensionless velocity =8.4 signals. Note that the plots shown are two-dimensional projections of five­ dimensional trajectories. <= ~ Our experience with fluidized beds &. E demonstrates that chaotic time series 8 &. analysis is a much more discriminating : ~ method for characterizing and ct monitoring fluidization state than conventional methods such as Fourier analysis. Thus, it should be possible to -6+------~ -6 12 use chaotic measures to design and Principal Component 1 control fluidized beds more effectively than in the past. Phase-space patterns reconstructed from fluidized-bed One control application that has pressure measurements. Each pattern is a two-dimensional already been developed is a fluidization projection of a five-dimensional trajectory. Note the significant control module now being incorporated pattern changes that occur as a result of changes in into uranium processing facilities at the fluidization state. Oak Ridge Y-12 Plant. An essential

42 Oak Ridge National Laboratory REVIEW component in the Y-12 control scheme is a device that reconstructs the fluidized bed's attractor from pressure measurements and continually analyzes its key features. 10 When the attractor structure begins to deviate significantly from optimum values, a control signal is sent to correct the bed operation, making it ...>­ operate more efficiently than was u 0 previously possible. .J w While continuing to work with > fluidized beds, we have expanded our scope of potential chaos applications into other areas such as pulsed 2 combustion, motor current signature analysis, nuclear reactor monitoring, and internal combustion engine diagnostics. Results from preliminary investigations in several of these areas are very encouraging. For example, using simplified computer models, we and collaborators from DOE's Phase-space trajectory of a thermally pulsed combustor illustrating chaotic fluctuations in combustion temperature and Morgantown Energy Technology pressure. Center have demonstrated that chaos can result from interactions among the basic heat, mass, and momentum balances in time series analysis on systems of interest to pulsed combustion (see the figure at right). Because detect subtle changes in their attractors that these same basic balances are present in most indicate the onset of undesirable performance flames, we believe that chaos may affect many or imminent failure of critical components. types of combustion. It is known that fluctuations Beyond providing improved diagnostics, we of flow, concentration, and temperature in flames anticipate that chaos theory will contribute to are often major factors in the production of the development of radically new control pollutants such as nitrogen oxides and unburned strategies. For example, chaos theory may be hydrocarbons. If such fluctuations are the product combined with pattern-recognition techniques, of deterministic chaos, it should be possible to use parallel computers, and high-speed algorithms chaos theory and chaotic time series analysis to for extremely rapid "on-line" decision making. develop totally new methods for reducing Sufficient data processing speed would allow undesirable combustion emissions from automobile the introduction of real-time control changes to engines, power plants, and waste incinerators. force the system to behave in a particular fashion. An example of an application of this Future Plans and idea would be in the development of "smart" monitors for automobile engines. Such Possibilities monitors could evaluate an attractor We plan to continue exploring the use of chaos representing engine performance and determine theory as a basis for engineering diagnostics. As if the pattern meets certain criteria (e.g., less described previously, we will attempt to use chaotic than some allowable maximum for production

Number Two, 1992 43 SEEKING ORDER IN CHAOS

of nitrogen oxide, an air pollutant). If the desired In summary, because it is appropriate for many performance criteria are not met, some technical disciplines and applications, use of appropriate parameter adjustment would be made chaotic time series analysis as a basic research (e.g., increasing the spark advance). Such tool and engineering methodology will likely adjustments, or "perturbations," could be made expand widely over the next few years. 11!:11 almost continuously to effectively mold the engine's attractor into its optimum form.

Suggested Reading The following short list of references is recommended for those interested in learning more about chaos:

James Gleick, Chaos: Making a New Science, Viking Pre s, New York. Nontechnical but very readable review of major developments and players.

Ian Stewart, Does God Play Dice?, Basil Blackwell, Cambridge, Massachusetts. Very readable introduction to the basic concepts and philosophy behind chaos theory.

G. L. Baker and J.P. Gollub, Chaotic Dynamics: An Introduction, Cambridge University Press, New York. Technical presentation of chaos at the undergraduate and first-year graduate student level.

Francis Moon, Chaotic Vibrations, John Wiley and Sons, New York. Technical introduction to chaos for engineers and applied scientists.

J.P. Eckmann and D. Ruelle, "Ergodic theory of chaos and strange attractors," Rev. Mod. Phys., Vol. 57, No.3, Part l, pp. 617--656. Highly technical discussion suitable for those familiar with chaos theory but not specifically acquainted with chaotic time series analysis.

44 Oak Ridge National Laboratory REVIEW Biographical Sketch

Stuart Daw (on left) is a development staff ORNL's Engineering Physics and Mathematics member in ORNL's Engineering Technology Division and Instrumentation and Controls Division. He holds a Ph.D. degree in Division to develop chaotic time series analysis chemical engineering from the University of as a generic research tool. As a result of this Tennessee. He served as a research and collaboration, Daw was a co-winner of a 1991 development engineer at E. I. du Pont de Technical Achievement Award from Martin Nemours and Company before coming to Marietta Energy Systems, Inc. He is a member ORNL in 1979. Three years ago, he became of the ORNL Graduate Fellow Selection Panel, interested in using chaos theory to describe the Board of Advisors of the Central States behavior in fluidized-bed reactors. Since then Section of the Combustion Institute, and the he has collaborated with researchers from American Flame Research Committee.

Number Two, 1992 45

------~~--

atteries are a familiar part of everyday which is watt-hours divided by battery volume in life. Many of us depend on heavy liters, and specific energy, which is watt-hours lead-acid batteries to start our cars; a divided by battery weight in kilograms. Although Bvariety of dry cells to operate cameras, toys, and a lead-acid battery in a car can produce a large portable sound systems; small lithium-iodine amount of energy, its energy density and specific batteries to power cardiac pacemakers; and tiny energy are low. On the other hand, lithium­ lithium- magnesium oxide coin cells to run manganese oxide coin cells in watches cannot watches. supply the same amount of energy, but their Packing more power into batteries while energy density and specific energy are much reducing their size and weight has become a goal higher. for researchers because of growing interest in At ORNL a group led by John Bates of the ORNL has smaller, lighter batteries for a variety of purposes. Solid State Division has developed a thin-film Tiny batteries smaller than a button are needed to lithium microbattery for computer memory chips developed a provide electrical energy for computer memory that is much thinner than plastic wrap. "The thin-film chips, medical implant devices, and purpose of these batteries is to hold the memory lithium radiofrequency transmitters in car key sets to until the power comes back," says Bates. If such prevent car theft. Medium-size batteries are useful a battery could be scaled up to propel electric microbattery for consumer electronics, such as laptop vehicles, he calculates it would be an for computer computers and cellular phones. Large-scale, improvement over the lead-acid battery by a lightweight batteries are needed to power electric factor of 8 in energy density and a factor of 10 in memory cars. specific energy. chips. A major issue in the development of new The main goal of the ORNL work, however, is batteries is the materials used. Many household to fmd ways to develop microbatteries for batteries contain lead, cadmium, and mercury-all microelectronics. Integrated circuits on silicon toxic materials. New Jersey now has a law that chips have made possible the reduction of requires manufacturers to eliminate mercury from computer size. As a result, modem appliances batteries by the end of 1995 and mandates that and cars are now controlled by microprocessors. collection programs be set up for certain batteries However, partly because of differences in the containing mercury, lead, or cadmium. levels of research activity and money, reduction The focus of research is to create batteries that in the sizes of batteries has not kept pace with the contain fewer toxic materials, are rechargeable, reduction in the sizes of electronic devices. and are able to pack in more energy per unit For example, consider nonvolatile computer weight and volume. Batteries using lithium have memory chips. They have nonrechargeable yielded promising results. batteries as backup so that the information stored The size and weight of a battery are generally as electronic charges is not lost in case of a thought to be related to the amount of energy it power failure. However, each lithium battery is stores. Hence, the larger a battery, the more many times larger than the chip using it. ORNL's electrical energy it can supply. Electrical energy is development of thin-film lithium batteries offers expressed in watt-hours-the product of the the means to scale down the sizes of batteries to current, voltage, and discharge time when the more closely match the sizes of microelectronic battery is in use. However, more important figures components. The ORNL work may result in the of merit for a battery are the energy density, first practical rechargeable microbattery.

John Bates examines a thin-film lithium battery in the light of the nitrogen glow discharge in the vacuum deposition chamber used to produce microbatteries at ORNL's Solid State Division. The nitrogen gas reacts with lithium orthophosphate to form a new battery electrolyte film discovered at ORNL. Photographs in this article by Bill Norris.

Number Two, 1992 47 THIN FILMS FOR ADVANCED BATTERIES

Battery on a Chip Greg Gruzalski, and Chris Luck, is to make thin­ film batteries that can be deposited directly either Solid-state processes for depositing thin films on the reverse side of a computer memory chip or on a substrate are being used at ORNL and onto the chip's protective ceramic package. "The elsewhere to increase the amount of energy that idea," he says, "is to incorporate the battery into can be stored in a battery per unit weight and the integrated circuits of computer memory chips volume. ORNL's Ceramic Thin Films Group in during their manufacture. This approach would the Solid State Division has made a number of eliminate the manufacturing step of oldering thin-film lithium microbatteries that have large batteries onto circuit boards." remarkably high specific energies and energy Bates believes that these solid-state thin-ftlm densities. The cells have open circuit voltages at batteries will also offer these advantages over full charge of 3.7 to 3.8 volts, the highest competitive technologies: achieved to date in a thin-film battery. This success has attracted the attention of the Eveready • They are rechargeable. Battery Company, which has also been • They have high power and energy densities. developing thin-film batteries. In March 1992, • They can be fabricated to virtually any size onto ORNL and Eveready signed a cooperative a variety of substrate materials, such as research and development agreement (CRADA) semiconductors, ceramics, and plastics. to facilitate the commercialization of thin-film batteries (see the section on "CRADA with • They can be fabricated using standard deposition Eveready" on p. 53 and the item in "Technology techniques and mild deposition conditions. Transfer" on p. 154). • They can operate over a wide temperature range, According to Bates, the current goal of the even at temperatures near the melting point of ORNL group, which includes Nancy Dudney, lithium; ORNL cells have·been operated between -l5°C and 150°C. • They contain no liquid components and produce no gases.

"Our thin-film battery," Bates says, "can be deposited onto any substrate that can withstand a Chris Luck shows temperature of 50°C, including a variety of a display model of a thin-film lithium polymers. In addition, the shape of the battery can battery that he conform to the shape of the support. For example, fabricated. The it could be fabricated on a cylinder. Our battery 3.7-V battery can can be made as small as any multilayer device or power the as large as the deposition equipment allows. For attached digital example, a thin-film battery could be deposited watch. On the onto an entire sheet of window glass." computer screen Bates and his colleagues have been searching is a schematic of for the right combination of materials to make the thin-film battery. reliable backup power sources for computer memory chips based on complementary metal oxide semiconductor (CMOS) technology. Currently, standby power for computer memory chips is supplied by nonrechargeable lithium­ manganese oxide or other lithium batteries, which are soldered to circuit boards or incorporated into a self-contained package. These batteries are

48 Oak Ridge National Laboratory REVIEW larger than the chips for which they provide required an extra layer of lithium iodide to protect backup energy. Someday they may be replaced by the electrolyte from attack by lithium. At ORNL smaller thin-fiJm lithium batteries based on the Bates' group has developed an even better cell ones developed at ORNL using a newly using an oxynitride-based electrolyte, which is discovered material for the electrolyte. stable with a lithium anode. The ORNL group is also adapting this microbattery technology for use in miniature Building a radiofrequency transmitters expected to be commercially available someday. The group Better Battery hopes to contribute to the development of scaled­ The ORNL research program began in up batteries for consumer electronics and electric November 1986 at a Materials Research Society cars (see sidebar on p. 56). meeting when Jim Roberto, director of the Solid State Division, heard a talk on microbatteries by Why Thin-Film Minko Balkanski of the Universiti Pierre et Marie Curie in Paris, France. There Roberto discussed Lithium Cells? with Bates the possibility of ORNL conducting Why did Bates and his colleagues choose to research in support of microbattery development. investigate thin-film lithium cells? First, they were In Apri I 1987, Bates and Dudney submitted a seed attracted to lithium's advantages. Because lithium money proposal entitled "Micropower Sources" has a small atomic mass and the highest and obtained internal funding from ORNL. By electrochemical potential for a metal, it makes a November 1987, they had their first vacuum good reactant for a battery that must have high chamber for film deposition. In June 1988, Bates cell voltage and high specific power. They chose and Dudney submitted a proposal on "Microionics: thin films for batteries because they make an Materials and Devices" and received support for effective cell which can be manufactured by the fiscal year 1989 from the Director's R&D Fund at same processes used by the electronics industry. ORNL. In November 1988 Bates' group fabricated Battery cell components can be prepared as thin the first vanadium oxide cell ever made at ORNL (-lJ..Lm) sheets built up as layers. The area and and possibly anywhere else. It marked the thickness of the sheets determine battery capacity. beginning of a series of successes for the group in Deposition of thin films increases the contact microbattery development. area of the ceiJ components, resulting in a high "Our work started from scratch," Bates says. fraction of reactants. Thin films result in higher "We had no deposition equipment and no current densities and cell efficiencies because the experience in thin films. We began our electrolyte transport of ions is easier and faster through thin­ studies using a lithium phosphosilicate system." film layers than in bulk materials. The electrodes of the ORNL thin-film battery The major challenge to the development of the are lithium (Li) and noncrystalline vanadium oxide lithium cells was to find an electrolyte that (Y20J Vanadium oxide was selected as the satisfactorily conducted ions and was stable in cathode because it is an intercalation compound contact with lithium. In the fall of 1991, groups at that permits a lithium ion to move into and out of a Eveready and the University of Montpellier in framework without causing more than a small France reported the development of solid-state expansion or contraction of the structure. Lithium rechargeable thin-film cells with lithium anodes. ions move into the vp5 structure during discharge The French group's cells had low current densities of the cell and are forced out of the structure and short lifetimes, but the Eveready cells had during recharge. The amorphous material is excellent current densities and were charged and preferred over the crystalline form because three discharged hundreds of times. The Eveready cells times more lithium ions can be inserted into the use a titanium sulfide cathode and an oxysuJfide­ amorphous cathode, thus making a battery that has based electrolyte. In both cases, however, the cells a higher capacity.

Number Two, 1992 49 A battery is one of two electrodes, and the reaction in which electrons kinds of electrochemical saltwater was the are released to an external devices that convert the electrolyte. circuit through the anode. energy released in a Familiar batteries of Simultaneously, a reduction "The first electric chemical reaction directly today are the flashlight (or reaction removes electrons battery may have into electrical energy. dry cell) battery, which from the external circuit In a battery, the uses manganese oxide and through the cathode. The been made in ancient reactants are stored close zinc for the electrodes and electrolyte functions to Egypt, but historians together within the battery a paste as an electrolyte, "control" the rate of reaction often credit Italian itself, whereas in a fuel cell and the lead-acid car between the anode and physicist Alessandro the reactants are stored battery, which uses lead cathode by forcing electrons Volta, who in 1800 externally. This conversion and lead oxide for the to move through external of chemical energy to electrodes and sulfuric acid circuits, producing energy. assembled a series of electrical energy is for the electrolyte. The However, the electrodes silver and zinc disks potentially 100% efficient, lead-acid battery, which must not touch each other to that sandwiched whereas the conversion of was invented in 1860, is avoid internal short circuits. cardboard disks chemical energy to unsurpassed for vehicle (See the examples of battery soaked in saltwater." mechanical energy via a uses because it can deliver reactions shown in the thermal conversion (e.g., a large current. schematic.) internal combustion of The electrodes are the Some cells operate as gasoline in cars) always positively charged pole two independent half cells in results in heat transfer (cathode) and the which reactions occur by ion losses limiting the intrinsic negatively charged pole exchange with the cell efficiency. (anode) of a storage electrolyte. For others, a net The first electric battery battery. The electrolyte is a cell reaction results in the may have been made in chemical compound that formation of a new ancient Egypt, but separates the electrodes compound such as lithium historians often credit and conducts ions released iodide or sodium sulfide. Italian physicist Alessandro during discharge. The Such a reaction requires the Volta, who in 1800 electrolyte forces the transport of an ion through assembled a series of electrons to flow in the the electrolyte from one silver and zinc disks that device's external circuits. electrode to the other. sandwiched cardboard Chemical energy is Among the important disks soaked in saltwater. converted into electrical characteristics of battery The disks served as energy by an oxidation cells are

50 Oak Ridge National Laboratory REVIEW Lead-acid battery RL e-- AAA I rvv l Uquid electrolyte H2S04 Anode Pb saturated Pb02 Pb Cathode with PbS04

Anode: Pb ---! Pb2+ + e 2 Cathode: Pb02 + 4H3o+ + 2e ---! Pb + + 6H20 2 Net: Oxidize and reduce Pb: Pb02 + Pb + 4H3o+ -l 2Pb + + 6H20

• Cell voltage-ideal or Alkaline manganese-dioxide battery open circuit voltage, which RL e HA is higher than the actual I -- rHv I cell voltage when the Paste electrolyte current flows through the NH4 CI Anode + c Cathode cell (cell efficiency is Zn Cl2 + determined by the ratio of H20 actual voltage to the ideal Anode: Zn ---! zn2+ + 2e voltage) Cathode: 2Mn02 + 2 H30+ +2e -l Mn2 0 3 + 3H20 2 • Power output-the Net oxidize Zn, reduce Mn: Zn + 2Mn02 + 2H3o+ -l Zn + + Mn20 3 +3H20 magnitude of the current Lithium-iodine battery that can be delivered at a RL e-- AAAi given voltage 'IVVV • Power density-power I I output per weight or Solid electrolyte Lii volume of the battery Anode Li I2 Cathode system, which includes the cell materials, reactants, Anode: u ---! u + + e and necessary packaging Cathode: u+ + 112 ~ + e -l Li I Net: Formation of Li I : 2Li = ~ -l 2Li I • Capacity-the amount of chemical reactants that can The schematic shows the chemical reactions in three different batteries that produce be stored and effectively electrical current. RL represents the resistance of the external circuit. used in the battery. Batteries rarely can be used until fully discharged, so that one of its reactants Batteries are designed the memory chips during is totally consumed differently for various electronic fabrication. For • Shelf life-the amount of applications. "For computer vehicle applications, the time a battery can retain its memory backup power," battery should offer high original properties when Bates says, "the battery energy density, large not in use should have the current output, full • Rechargeability-the appropriate cell voltage, a rechargeability, rapid ability of the battery to be long shelf life, recharge, safety, and a restored to a useful rechargeability, and the reasonable cost." condition. ability to be integrat~ with -Carolyn Krause

Number Two, 1992 51 THIN FILMS FOR ADVANCED BATTERIES

conductivity of amorphous lithium phosphate having the composition 9 0.6Lip:0.4Pp5 is 10 times as high as that of crystalline lithium

). orthophosphate (Lil04 To avoid the need for a layer of Nancy Dudney lithium iodide to protect the examines a thin­ electrolyte from being attacked by film lithium battery lithium, Bates consulted the in the protective literature for some clues. "I learned atmosphere of a that adding nitrogen to sodium glove box. metaphosphate glasses improves their durability in contact with air and water vapor. So we decided to sputter the lithium orthophosphate in nitrogen rather than the standard gas mixture of argon and oxygen. The resulting film was an oxynitride that contained about 3 at. % nitrogen. It seems that nature much prefers oxygen to nitrogen in compounds such as these, but the presence of this small amount of nitrogen greatly improves the performance of the electrolyte." Currently, the electrolyte used exclusively in ORNL's thin-film lithium batteries is Lithium phosphorus oxynitride (LiPON), the first film of which was grown In a thin-film lithium cell (see the schematic at ORNL in February 1991. The LiPON electrolyte, diagram of its operation on p. 53), lithium ions which is deposited over the cathode, outperforms leave the anode, diffuse through the electrolyte competitive electrolytes, such as the oxysulfide \ film, and reach the Vp5 cathode. At the same electrolytes employed by Eveready. time, electrons travel through the external circuit To analyze the composition of the electrolyte, the to power a device and then to the cathode to group has relied on resonance ion backscattering "combine" with the Li+ ions so that the compound performed by Ray Zuhr of the Solid State Division, retains a net neutral charge. The cell reaction can electron spectroscopy for chemical analysis and be represented as Auger electron spectroscopy carried out by Ashok Choudhury of the Metals and Ceramics Division, and proton-induced gamma emission analysis conducted by their collaborator, Dave Robertson, of In their effort to develop an improved the University of Kentucky at Lexington. electrolyte, the ORNL scientists took into account "Tests show that the nitrogen-containing the fact that many inorganic compounds are better electrolyte has 30 times the lithium ion conductivity ionic conductors in the amorphous state than in of a film of pure amorphous lithium ortho­ the crystalline form. For example, the phosphate," Bates says. "This is important because

52 Oak Ridge National Laboratory REVIEW every battery has an internal resistance to ion transport. Our "ATOMIC" SCALE BATTERY goal is to overcome this resistance by increasing the ion 0 0 0 0 conductivity of the electrolyte. The result will be a better battery." 0 0 0 0 Li Anode How Film Is

Deposited 0 0 0 The thin-filin lithium cell is 0 Li Electrolyte fabricated at ORNL by (Li3 P04) depositing successive layers of the cathode, electrolyte, and anode using direct-current and radiofrequency magnetron ' ------· ·~'-- p sputtering and thermal : :i : : 0 evaporation. The battery is only 6 microns thick, or one-third the thickness of plastic wrap (a · ·~ · ~·· · ···· o~ micron is a millionth of a meter), and cells have been deposited on • V 20s Cathode alumina or glass substrates. Magnetron sputtering is done in a vacuum chamber at near room temperature in pure argon, oxygen, and nitrogen gases. A thin 2.5-cm-diam disk of a target How ORNL's thin-film lithium battery works is shown here material is loaded into a schematically on an atomic scale. The lithium oxidizes, diffuses commercial magnetron sputter through the electrolyte as an ion, and intercalates (inserts itself) source. The targets are vanadium into the reduced vps cathode.

metal for the cathode and Lil04 for the electrolyte. A high voltage is applied to the target material. At low "Currently, the deposition rates are quite low gas pressures, the voltage generates a plasma because pushing for a more rapid rate of film discharge. The positively charged ions in the growth would sacrifice the film's uniformity and plasma are accelerated to the target material quality," Bates says. "But tltis production problem because of its negative charge, and upon should be considerably reduced when larger bombardment, some of the target atoms are sputter sources are employed." ejected, or sputtered. The final cell layer, the lithium anode, is The sputtered atoms then condense on the deposited by thermal evaporation under vacuum. battery substrate positioned about 5 em from the sputter target. Permanent magnets positioned CRADA with Eveready beneath the target enhance the sputtering efficiency by confining the electrons in the plasma The ORNL group has apparently solved the close to the target surface, thereby increasing the problem of lithium attack on the thin-film ionization of the atoms in the sputtering gas. electrolyte. However, a remaining problem that

Number Two, 1992 53 THIN FILMS FOR ADVANCED BATTERIES

allows researchers to try out ORNL's ideas rapidly. The deposition rechargeable thin­ li I VOx Rechargeable Thin-Film Battery system at Eveready is much film lithium­ vanadium oxide larger because it is designed for battery is small production runs, not fabricated by research. deposition of three "We will work with Eveready layers on the on determining which material vanadium current could best seal up the battery collector-the without altering the properties of cathode our films," Bates says. "We are (amorphous vanadium oxide, testing the results of depositing a ), variety of materials onto the or Vp5 the electrolyte (lithium lithium as a sealant film." phosphorus Bates predicts the group will oxynitride, or 2 develop a self-contained thin­ UPON), and the film battery of more than 3.5 Vanadium geometry anode (lithium, volts during 1992. Then he hopes or Li). the group may become involved in research on scaling up thin­ film batteries for use as lightweight, energy-efficient sources of power for electric cars (see sidebar "From Chips to Cars").

Future of Thin-Film Battery Research

3 4 The use of LiPON in thin-film batteries will make possible Li+ electrolyte I VOx I V Li I Li + electrolyte I VOx I V higher voltage cells based on lithium cobalt oxide (LiCo0 ) or 2 lithium manganese oxide (Li 2 M~04). Raising the voltage must be addressed is protecting the lithium from of these cells is important because it increases corrosion in air. Currently, thin-film batteries their energy density. must be stored in a protective argon atmosphere. Another goal of the ORNL research is to "We must find a way to seal up the battery and enhance the current density and pulse capability make it self-contained," says Bates. of the thin-film cells. One problem in the ORNL The researchers are now working on a project cell is that the current appears to be limited by to package thin-film batteries under a CRADA lithium ion transport in the vanadium oxide signed in March 1992 between Energy Systems cathode. and the Eveready Battery Company. Eveready The discovery of lithium phosphorus had approached ORNL about a cooperative oxynitride and its excellent properties as an research effort because the company had not electrolyte has opened up a new area of research found a packaging solution and because the for thin-film materials, which will be explored in smaller-scale deposition equipment at ORNL a Basic Energy Sciences program of the

54 Oak Ridge National Laboratory REVIEW Dudney, Bates, and Luck examine the digital watch powered by the thin-film lithium battery they developed. The electrometer shows that the battery voltage is 3.35 Vwhile powering the watch.

Department of Energy. In addition, the new field In conclusion, the program started by Bates, of microionics could become a major target of Dudney, and others could expand to scale up research at ORNL. microbatteries being developed for computer "We hope to continue to focus our basic chips into macrobatteries that could be useful in research on improving battery technology," Bates many ways, including powering electric vehicles. says. "Our work in microbatteries and our work Use of thin films for batteries to power everything with other groups on microelectronics could be from chips to cars may someday be seen as a extended to development of, for example, classic example of getting more from less. mJ miniature radiofrequency transmitters and remote microsensors for environmental or biomedical applications."

Number Two, 1992 55 Thin Films for Advanced

I n the fall of 1991 , the make the United States sulfide (Li/FeS) batteries. U.S. government gave a more competitive in battery The lithium-iron sulfide jump start to the nation's research and electric battery has higher specific battery research by vehicle development; energy and energy density combining its resources nations taking the lead in than the other two.. with those of the Big Three these areas are Great However, according to automakers in Detroit. Britain, Germany, Japan, Bates, a scaled-up thin-film Because of renewed and Canada. lithium battery would be an "DOE has concerns about air pollution ORNL is expected to be improvement over the established an and future oil shortages, named a lead laboratory for lithium-iron sulfide battery Advanced Battery there has been a DOE and the consortium in by a factor of about 4 for Consortium in which resurgence of interest in at least one area of electric specific energy and by a national laboratories, electric cars. But to be vehicle development: factor of about 5 for energy acceptable to the public, lightweight body materials. density (see table). universities, and such vehicles will need ORNL may also play a role "Improved power density other companies will batteries that are low in in the development of is achieved by using a collaborate on cost and able to keep the electric vehicle battery lithium battery," Bates says. battery research with vehicle operating for many materials. "By making a thin-film Ford, Chrysler, and miles before a recharge is The potential competitors battery, we hope to needed. In addition, the for electric vehicle increase the maximum General Motors." time to recharge the battery propulsion include lead­ discharge current and should be short. acid (Pb/acid) batteries, decrease the time required DOE has established an sodium-sulfur (Na/S) to recharge the battery." Advanced Battery batteries, and lithium-iron Consortium in which national laboratories, universities, and other companies will collaborate on battery research with Ford, Chrysler, and General Motors. The latter company is already developing electric vehicles that would use lead-acid batteries. One reason for this move by DOE is to

56 Oak Ridge National Laboratory REVIEW Waste R&D At ORNL

By Diedre Falter

n the past few years efforts to clean up • Robotics--developing robotic systems and hazardous waste at sites across the remote technology to characterize and clean up I country, including Department of Energy waste without exposing workers to a hazardous facilities, have increased dramatically. Vast environment; economic and personnel resources are being devoted to environmental restoration. Sometimes • D&D---decontamination and decommissioning problems can be solved quickly using available of metals and concrete to assist in disassembling techniques; however, solving many old old facilities and in replacing several major environmental problems requires new methods and facilities in the Defense Programs technologies. Creating these new approaches is the Reconfiguration; task of the Office of Technology Development (OTD) within DOE's Office of Environmental • Transportation-performing evaluations of Restoration and Waste Management. transportation needs for on-site and off-site The success of this task depends to a transfer of hazardous and mixed waste (hazardous considerable degree on maintaining open lines of and radioactive waste combined); and communication between OTD and its counterparts, the Office of Environmental Restoration and the • Technology transfer-promoting the transfer of Office of Waste Operations. These organizations technologies developed at ORNL that potentially ORNL is are involved in the nuts and bolts work of could improve program effectiveness, reduce restoration, remediation, and waste management, costs, and save time for federal agencies, industry, developing often responding to crisis situations. During the academia, and the international community. innovative course of this work, some areas are found to have environmental cleanup and waste management needs that cannot AU these activities involve developing new be met with existing technologies. OTD's mission remediation and waste management methods or restoration is to be attentive to these areas, seek out possible modifying existing techniques to create cost­ and waste solutions, and nurture their development so they effective, energy-efficient waste-minimization can be implemented in the field. technologies. management At ORNL, innovative environmental restoration technologies. and waste management techniques for OTD are Characterization in being developed the following areas: Finding more economical ways to clean up soil and groundwater contaminated by radioactive and • Characterization--developing advanced models, hazardous chemicals is a priority in environmental field measurement and sensing methods, and data restoration and waste management. The fust step acquisition and analysis systems for mapping and toward reducing the cost of cleaning up sites is determining the contents of a waste site; reducing the cost of collecting and analyzing soil and groundwater samples. The process of • Bioremediation---developing microorganisms to collecting and analyzing samples is not only "eat" or otherwise stabilize selected organic costly, but it also delays cleanup efforts because contaminants, such as trichloroethylene (TCE) and of the time required to obtain results. The Office polychlorinated biphenyls (PCB), and inorganic of Technology Development is currently species, such as uranium and lead, in situ (in place) supporting a number of projects at ORNL or in process; addressing these problems. For example, ORNL researchers Marcus Wi se, • Treatability--developing methods for treating Cyril Thompson, and Mike Guerin, all of the soils contaminated with volatile organic Analytical Chemistry Division, have developed a compounds and low levels of radioactive portable, real-time, direct-sampling ion-trap mass substances; spectrometer that can detect hazardous organic

Number Two, 1992 57 WASTE R&D AT ORNL

Meanwhile, nondestructive assay and nondestructive Cyril Thompson examination methods operates the using a Linear Analytical accelerator have been Chemistry developed for Division's portable characterizing remote­ direct sampling handled transuranic ion-trap mass (RH-TRU) waste by spectrometer, Fred Schultz of the which can detect Office of hazardous organic Environmental and compounds at Health Protection extremely low Compliance. concentrations, Tuan Vo-Dinh of reducing sample the Health and Safety processing time Research Division is by half. developing a luminescence spot test for rapid screening of soils to find out if they contain PCBs. In this technique, the presence and concentration of PCBs adsorbed on compounds at extremely low concentrations. This chemically treated filter paper and exposed to device reduces sample processing time to less than light are determined by detecting and measuring half that required using conventional analytical their resultant luminescence. Advantages of the methods (see sidebar on p. 80). technique are that the simple instrumentation can The improved Derivative Ultraviolet be easily set up and used in the field and that it Absorption Spectrometer (DUV AS) system can analyze samples more rapidly and at a lower developed by John Haas of the Health and Safety cost than conventional methods. Re earch Division measures groundwater Some effort at ORNL has been devoted to contamination directly and, as a result, is able to developing technologies for analyzing air, water, more accurately characterize any such and soil in place, thus reducing considerably the contamination. The system may have additional cost, time, and hazards associated with extracting, applications in the monitoring of manufacturing transferring, and analyzing contaminated samples. discharges and chemical process streams (see Haas has been building a fiber-optic probe and sidebar on p. 83). monitoring system using DUV AS to provide fast, The colloidal borescope previously developed cost-effective in situ sampling of groundwater to by Tom Cronk and Pete Kearl, both of ORNL's identify its contaminants. At the same time, Roger Grand Junction, Colorado, office, is being adapted Jenkins of the Analytical Chemistry Division is to measuring the velocity of groundwater flow. developing an arrayed multisorbent sampler- an This instrument offers the potential for improved array of tubes packed with layers of various site characterization, design of faster and more materials that adsorb volatile organics- for in situ cost-effective remediation strategies, and collection of volatile species at depths up to 38 m improved monitoring of the remediation process. ( 125 ft). An example of such an organic pollutant

58 Oak Ridge National Laboratory REVIEW is TCE, a solvent that had been widely used to remove grease from metal. The samplers will provide temporally and spatially resolved chemical information concerning the impact, effectiveness, and zone of influence of candidate remediation technologies. Considerable time and money can be saved by identifying the technologies ''Considerable already available and establishing procedures for time and their use. Wayne Griest, Gary money can Sega, and Bob Schenley, all of the Analytical Chemistry be saved by Division, are adapting identifying analytical methods already the approved by regulatory By detecting and measuring the concentration of groundwater agencies to the contaminants directly, rather than by "sniffing" the air above the water, technologies characterization of mixed the DUVAS system, displayed here by John Haas of the Health and already wastes and radioactive Safety Research Division, is able to more accurately characterize environmental samples. groundwater contamination. available and Bioremediation establishing A number of hard-to-degrade volatile organic Two types of contaminants, perchloroethylene procedures compounds, uch as TCE, have been identified as (PCE) and PCB, are effectively nondegradable for their groundwater and soil contaminants at DOE sites. under aerobic (oxygen-rich) conditions, but they use. " These contaminants are of particular concern not may be broken down into harmless substances in only because of their potential toxicity but al so an anaerobic (oxygen-free) environment. At least because of their movement through oils as two OTD projects at ORNL are focused on vapors and in water. New technologies are developing techniques to break down these needed to remove these contaminants from chemicals in anaerobic environments. For instance, groundwater and soil and to safely dispose of Terry Donaldson, Thomas Klasson, and Betty them. Evans, all of the Chemical Technology Division , For example, the popular method of air are working to identify and cultivate naturally stripping results either in the discharge of TCE to occurring anaerobic bacteria that break down PCB the atmosphere or its capture on activated carbon, molecules by eating and digesting them (see which itself must then be disposed of. In either sidebar on p. 65 ). Likewise, Steve Herbes and case, the TCE is not actually destroyed. A more Mike Morissey, both of the Environmental viable solution seems to be bioremediation, which Sciences Division, are exploring methods to assist is based on the use of organisms to destroy the cleanup at the Savannah River Site by contaminant at the site, thus avoiding the risks to anaerobically degrading PCE and other organic worker safety of handling, transporting, treating, compounds resistant to biological treatment using or storing contaminated residuals. existing commercial processes.

Number Two, 1992 59 WASTE R&D AT ORNL

soil and water deep underground at the Savannah River Site. Remediation of TeE­ Treatability contaminated water using Waste retrieval and bioreactors, such waste processing .as that being currently constitute the operated by largest segment of the Chemical mission of DOE's Office Technology of Environmental Division engineers Hal Jennings and Restoration and Waste Andrew Lucero, Management. Current relies on the use technologies for treating of naturally contaminated materials to occurring eliminate their toxicity or organisms to removing them from sites destroy the and processing them into contaminant at a suitable form for the site, shipping or disposal are el iminating the need for handling, often inadequate and transporting, expensive. In situ treating, or storing vitrification is one contaminated promising technology residuals. that instantly destroys many hazardous components and immobilizes the remainder by trapping them in a block of glass Because bioremediation approaches that exploit or slag with minimal personnel exposure. Gary existing bacteria or green plants are more socially Jacobs and Brian Spalding, both of the acceptable than using engineered microbes, Environmental Sciences Division, successfully Barbara Walton and Nelson Edwards, both of the demonstrated this technique on a trench Environmental Sciences Division, are studying the containing radioactive materials (see a effects of vegetation on the bioremediation of description of this demonstration on p. 78 of the soils contaminated with TCE and PCE. In Number Two, 1991, issue of the Review). particular, they will determine whether certain A Chemical Technology Division team plant species and fertilizers speed up the rates at consisting of Lloyd Youngblood, Jr., Zane Egan, which TCE and PCE decompose in soil. Klassen, and Donaldson is adapting previously Meanwhile, Tony Palumbo of the same division is developed techniques for the chemical coordinating a soil bioremediation team including destruction of PCB-contaminated cooling oils scientists from both the University of Tennessee and electrical transformer oils to the treatment of and the University of Minnesota. They are using DOE's mixed wastes. Youngblood is also innovative methods of monitoring microbial addressing the concern about the integrity of activity in the soil to measure the effectiveness of aging tanks containing mixed wastes by trying to bioremediation of TCE- and PCE-contaminated determine the best method for removing the

60 Oak Ridge National Laboratory REVIEW sludge from these tanks before they begin to leak. The ORNL team seeks to develop robotic Mixed wastes offer plenty of tough problems for technology for applications involving underground researchers to solve. For instance. many aqueous storage tanks, buried wastes, waste minimizati on, mixed waste streams contain concentrations of contaminant analysis automation, waste facility nitrate that exceed drinking water standards. AI operations. and decontaminati on and Mattus of the Chemical Technology Division is decommissioning associated with DOE facilities. searching for ways to chemically reduce the Research efforts in the characteri zation and nitrates contained in these mixed waste streams, remediati on of underground storage tanks are led producing gaseous ammonia and achieving by Barry Burks ofORNL's Robotics and Process acceptable nitrate levels. At the same time, Chet Systems Division. Recentl y. a team led by Burks Francis of the Environmental Sciences Division is achieved tremendous success in appl yi ng hot on the trail of a method for selectively computer-based laser imaging techniques to removing uranium from soils containing high mapping the surface topology of radon-emitting concentrations of silt or clay. Selectively removing uranium ore residue stored in silos at what used to the uranium would be much less costly than be the Fernald Feed Materials Production Center in transporting. storing, and monitoring of tons of Ohio. The accuracy of the surface maps has contaminated earth. enabled workers to precisely apply a foot-thick contaminant barrier of low-permeability clay over Robotics the waste to reduce radon emissions. saving DOE millions of dollars in remedial acti on costs (see In the movies, robots are literally able to " boldly sidebar on p. 86). go where no one has gone before" and save human ORNL 's efforts in remote characterization of adventurers from ri sking life and limb. Real-life buried waste sites are being led by Brad robots are being developed at ORNL and elsewhere Ri chardson and Mark Noakes. both of the Robotics to help reduce or eliminate the risks of exposing and Process Systems Division. Previous personnel to radioactive or hazardous wastes. coll aborative work with the U.S. Army is now Researchers are applying the principles of robotics being extended toward development of a special to develop servomechanical devices that low-ferromagnetic signature vehicle that will incorporate sensors, computer control, and human­ signi ficantl y improve the performance of machine interfaces for efficient remote operations subsurface mapping sensors. and a new ORNL­ under hazardous conditions and for improvements Army collaboration is seeking to adapt a military in productivity. Typically, a robot possesses backhoe to remote excavation of buried waste sufficient autonomous control capability to perform trenches and contaminated soil s. many of its functions automatically, but more Members of Hamel's team are working on difficult tasks are supervised and guided by a robotics projects with researchers at other DOE human operator who is remotely located--out of sites who are supported by the Robotics harm's way. Technology Development Program. These ORNL researchers are focusing on developing a collaborations are ex pected to resul t in sign ifi cant practical robotics technology to reduce the hazards progress in applying robotics and remote and costs of cleaning up DOE sites. The work is technology to the cleanup of DOE sites. being carried out by a research team headed by Bill Hamel, who also serves as one of the National Technology Transfer Robotics Program coordinators. This team forms an important part of the Robotics Technology The need to make the world a healthier, cleaner. Development Program in OTP. This national and safer pl ace to live in has motivated people robotics effort is addressing needs at many DOE everywhere to join together to solve a common laboratories and weapons and materials production problem--cleaning up the environment. Tom sites. Gagnier, coordinator of the Office of Technology

Number Two, 1992 61 Researchers are developing robotic devices that incorporate sensors, computer control, and human-machine interfaces to characterize waste under hazardous conditions.

Development environmental technology transfer putting together a cooperative research and efforts at ORNL, plays a key role in thi effort by development agreement (CRADA) with a U.S. promoting the sharing of technologies among firm to develop biosorbent technology for other federal agencies, industries, educational remediation of 14 German sites where uranium facilities, and international communities to mining and milling operations were carried out improve efficiency, reduce costs, and save time in from 1949 until they were clo ed in 1990. The environmental cleanup. technology employed may also be customized for Tom Mayfield of the Office of Technology use at other sites, including those in the United Transfer of Martin Marietta Energy Systems, [nc., States. is already heavily involved in at least two projects The technical exchange goes both ways. ORNL at ORNL that do just that. For instance, ORNL has entered into a collaborative agreement with a scientists led by Brenda Faison of the Chemical laboratory in Germany and several other DOE Technology Division have identified facilities in which ORNL personnel led by Robert biosorbents-biological tissue that will bind Siegrist will have the opportunity to study unique metal, removing it from solution-that technologies developed at the University of significantly reduce levels of uranium, strontium, Karlsruhe in Germany, including a groundwater cesium, lead, silver, iron, cadmium, and copper in well system used to manipulate and treat contaminated process fluids. The team is now contaminated soil and groundwater and an in situ

62 Oak Ridge National Laboratory REVIEW biotechnology treatment system. In addition, the complex. In addition, someone must make sure parties involved will study other approaches and that the research being conducted at ORNL is technologies that have potential applications in actually implemented in the field. These tasks all both countries. fall under the jurisdiction of the Office of Waste Research and Development Programs, directed by Integration Tony Malinauskas with the aid of Norm Cutshall and Jan Pruett. The goal of this office is to ensure Somehow, all of these diverse activities have to that ORNL becomes a valuable source of model be brought together. To make sure that important technologies for improving the economics and information does not fall through the cracks, the effectiveness of DOE's waste management and ORNL team must interact not only with our environmental restoration efforts. a counterparts at the other Energy Systems sites but also with our colleagues throughout the DOE

Biographical Sketch Diedre Falter is completing a year-long assignment in the Waste Research and Development Program Office at ORNL, where one of her first assignments was to write this article for the Review. After working as a laboratory supervisor at Transducer Research, Inc., of Naperville, Illinois, and receiving her B.S. degree in engineering physics from Murray State University in 1986, she joined ORNL's Instrumentation and Controls (I&C) Division. There she helped develop detectors for use in radiation detection, genome sequencing, radiometry, and high­ temperature thermometry. She was project leader of a team that received a 1990 Martin Marietta Energy Systems Technical Achievement Award for development of a microminiature infrared transmitter. As a result of that work, she was awarded her first patent. She has spent several years coordinating precollege (K-12) activities and internships for the I&C Division. Her husband is an engineer in the I&C Division.

Number Two, 1992 63 New Waste Technologies By Jim Pearce

A growing national concern over contamination of the soil, the water supply, and even the air we breathe is one of the driving forces behind current efforts by government and industry to more aggressively address the problems associated with hazardous waste management.

Several factors have contributed to this increased concern over environmental contamination. Recent studies have shown that many commonly used compounds, previously thought to be harmless, are powerful pathogens, mutagens, and carcinogens. Also, as more is learned about the effects of chemical pollutants on the environment, researchers are finding that levels of contamination previously considered insignificant can have serious environmental consequences. These findings both reveal a threat and present a challenge. The threat is obvious. We are inexorably tied to the environment-we cannot afford to kill it. The challenge is to stem the tide of waste and to develop ways of cleansing and reclaiming areas that have already been fouled. To meet this challenge, ORNL researchers in a range of disciplines are developing the tools needed to determine the type and extent of environmental contamination, to remove those contaminants from the environment, and to monitor potential waste sources to prevent further releases. A number of these projects are described in the following pages.

64 Oak Ridge National Laboratory REVIEW Foryears, poly- also the properties that to add oxygen atoms to the chlorinated biphenyls make them so long-lasting congeners. Oxidation of (PCBs) were considered in the environment. Until these congeners breaks ideal insulating fluids for recently, conventional them down into carbon transformers and other wisdom was that PCBs dioxide and water. electrical equipment were impossible to degrade "The more chlorine because they are biologically. However, in atoms a molecule has, the "Ironically, the same nonconductive, inert, and the last decade, research more difficult it is to properties that make chemically stable. has shown that certain oxidize," says Terry PCBs good After years of microbes can break down Donaldson of the Chemical insulators--their widespread use, these PCBs into harmless Technology Division (CTD). stability and lack of chemicals were determined substances, but only slowly "Molecules with more than to be potential carcinogens, and selectively. four or five chlorine atoms reactivity--are also and their production was PCBs are a large class are very difficult to oxidize." the properties that banned in 1977. By that of chlorinated (chlorine- The inability of aerobic make them so long- time, PCB contamination of containing) biphenyl organisms to degrade lasting in the soil and water from the chemicals, known as these highly chlorinated environment." deterioration of discarded congeners, that differ molecules may be partly equipment and discharges primarily in the number of the result of "steric from manufacturing chlorine atoms they hindrance"-the presence processes had become an contain. As a result, PCB of so many chlorine atoms environmental concern. contamination may involve prevents the microbial Further evidence of the several different enzymes from getting close serious nature of the congeners, each of which enough to the biphenyl problem is DOE's is treated differently by backbone of the molecule $350-million phased plan different microbes. to oxidize it. to clean up PCB How Microbes Degrade Fortunately, researchers contamination at the K-25 PCBs. There are two have found that certain Site in Oak Ridge and pathways for microbial PCB anaerobic microbes- uranium enrichment plants degradation. In an aerobic, organisms that exist in an in Paducah, Kentucky, and or oxygen-containing, oxygen-free environment- Portsmouth, Ohio. environment, congeners can remove chlorine atoms Ironically, the properties containing fewer than five from highly chlorinated that make PCBs good or six chlorine atoms can molecules. Once the insulators-their stability be degraded by aerobic molecules have been and lack of reactivity-are microbes that use enzymes stripped down to fewer than

Number Two, 1992 65 Technologies

The dechlorinating properties of anaerobic microbes are studied by placing the microbes in a soil-water slurry in 1-liter bioreactors, which are then spiked with a particular type of PCB. Periodic sampling allows researchers to measure the amount of dechlorination that takes place.

four or five chlorine atoms, "Looking for these microbes can probably they can be oxidized by organisms in PCB- degrade a wider range of aerobic organisms. contaminated areas is a PCB compounds." "Figuring out how to For the past several good strategy," says To obtain optimum manipulate years, Mark Reeves and Donaldson. "The performance from these metabolism is an Betty Evans, also of CTD, microorganisms at microorganisms, Reeves art." have been working in the contaminated sites have and Evans studied the laboratory to isolate had time to adapt to the effects of various nutrients microorganisms that can presence of PCBs and are on microbial metabolism by degrade a broader range of more likely to have the varying their diet. As in congeners more efficiently biological qualities we're humans, the type and and to find ways of looking for." amount of nutrients enhancing their The microbial cultures microbes receive affect performance. They have found on the ORR consist their metabolic behavior. searched PCB- of several types of Most microbes require contaminated soil on the organisms, but no attempt nitrogen, potassium , Oak Ridge Reservation has yet been made to phosphorus, and trace (ORR) for microorganisms culture a pure strain of levels of minerals, metals, with a particular talent for microbe. "The advantage of vitamins, and other degrading PCBs and have using a mixed culture," nutrients. "Figuring out how found several likely Donaldson says, "is that a to manipulate metabolism candidates. mixed population of is an art," says Donaldson.

66 Oak Ridge National Laboratory REVIEW ORNL researchers are using anaerobic microbes to break CI CI CICI Cl down highly chlorinated Cl -0--C:>- Cl c1-0-b PCBs into molecules having CARBON DIOXIDE AEROBIC only three or four chlorine Cl ANAEROBIC WATER + MICROBES atoms. These less­ Cl Cl Cl Cl + MICROBES CICI CHLORIDE chlorinated molecules can CI<>--0-CI CI -0--0-CI then be degraded further by aerobic microbes, leaving HIGHLY CHLOR INATED 3- AND 4-CHLORINE PCB MOLECULES PCB MOLECULES only carbon dioxide (C02), water (H20), and chloride (CI).

"The goal of this "The relationships between amount of dechlorination remediation techniques are microbe metabolism and that has taken place. "The likely to be site-specific," research is to diet are not very well degradation process is says Donaldson. "One accelerate the understood." slow," Donaldson says. "An approach to treatment development and Working toward field experiment may take six to would be to place the testing of new tests. Before field testing nine months." However, contaminated soil in a tank technologies for the begins at ORNL, small­ results from recent tests along with water, nutrients, scale bioreactor tests of indicate it may be possible and the microbial culture. biodegradation of remediation techniques are to accelerate the This approach would let us PCBs to meet Martin being used to investigate degradation rate. control conditions closely, Marietta Energy the dechlorinating effect of The goal of this research but it's cost-intensive. As Systems cleanup anaerobic microbes. The is to accelerate the we gain experience with standards." bioreactors are 1-L glass development and testing of the process, we want to be containers filled with a soil new technologies for the able to treat the soil in slurry-a mixture of soil, biodegradation of PCBs to place." water, and microbes. meet Martin Marietta These containers are Energy Systems cleanup generally spiked with a standards, which are as particular PCB congener, low as 2 parts per million in and samples are taken and solid materials. analyzed every two to four "When we get this weeks to measure the technology into the field,

Number Two, 1992 67 Technologies

I n 1944, the U.S. Army decomposition (BCD) recycling old transformers. drove the Japanese from process. The CRADA combines this Kwajalein Atoll in the South The BCD process is experience with ORNL's Pacific. Nearly fifty years currently being developed chemical engineering later, the Army is fighting a under a set of agreements expertise and ability to different kind of battle on among ORNL; S. D. Myers, select and conduct the Kwajalein-against Inc.; DOE's Hazardous development activities "Conventional potential environmental Waste Remedial Actions necessary to design a BCD technologies can contamination resulting Program (HAZWRAP); and system. After the decontaminate oils from its decades-long the Environmental technology has been presence on the island. Protection Agency (EPA). successfully demonstrated with PCB One of several Cliff Brown and Lloyd on Kwajalein, S.D. Myers concentrations of a environmental concerns is Youngblood, both of will be able to market it in few thousand parts a collection of 1 00 electrical ORNL's Chemical the private sector. Several per million or less. transformers at the U.S. Technology Division, are organizations have already The BCD process can Army Kwajalein Atoll. This working under a expressed interest in a cooperative research and system capable of treating potentially handle equipment is filled with about 15,000 gal of development agreement oils containing high levels oils containing askarel, an insulating oil (CRADA) between Martin of PCBs. concentrations of containing high levels of Marietta Energy Systems, DOE also has a vested 100,000 parts per polychlorinated biphenyls Inc., and S. D. Myers to interest in seeing BCD million or greater." (PCBs). refine the process so it can technology through to its The Army is considering be scaled up and moved fruition because of its several options for out of the laboratory. "Our potential for treating the destroying the goal," says Brown, "is to large quantities of PCB- contaminated oil, including get this technology in the contaminated mixed waste shipping it back to the field and demonstrate it on (containing both radioactive mainland for destruction in Kwajalein." and hazardous chemical a specially designed S. D. Myers' staff have a wastes) sludges, soils, and incinerator, bringing a wealth of experience in oils stored at Oak Ridge portable incinerator to building and operating and other DOE sites. Kwajalein, or using a transformer oil The BCD process was noncombustion chemical decontamination systems, originally developed by the technology, such as the and they specialize in EPA at its Risk Reduction base-catalyzed decontaminating and Engineering Laboratory in

68 Oak Ridge National Laboratory REVIEW Cincinnati, Ohio. In this process the PCB­ contaminated oil; an uncontaminated "donor" oil, used as a source of hydrogen atoms; sodium hydroxide; and a carbon Researchers are currently conducting bench-scale catalyst are reacted studies of the effects of together at high changes in temperature, temperature. "As a result," reaction time, mixing, and says Youngblood, other BCD process variables. "hydrogen atoms from the donor oil take the place of the chlorine atoms on the PCB molecules, leaving PCB concentrations of a solution to its PCB problem environmentally few thousand parts per are the efficiency of the manageable biphenyl million or less. The BCD process and its cost of molecules. The sodium process, on the other hand, implementation. then reacts with the can potentially handle oils Current research at displaced chlorine atoms to containing concentrations ORNL involves bench­ form salt." Plans are for of 100,000 parts per million scale studies of the effects waste oil from the process or greater. of changes in temperature, to be recycled and burned The most obvious reaction time, mixing, and to provide the heat advantage to using the other process variables. (approximately 300°C) BCD process is that the "Once these variables are required to sustain the destruction of the PCBs understood," says reaction. can be accomplished on­ Youngblood, "the next step BCD processing site, avoiding the risk will be to optimize the potentially extends the involved in shipping chemistry of the process range of noncombustive thousands of gallons of and work out the details of PCB decontamination hazardous material 6900 transferring the process technologies by several kilometers (4300 miles) to from the laboratory to the orders of magnitude. the mainland. Other factors field." Conventional technologies to be considered by the can decontaminate oils with Army before choosing a

Number Two, 1992 69 Technologies

Trichloroethylene (TCE), discontinued in the United TCE is now one of the most a potential carcinogen, was States by the early 1980s. commonly found "In a process known widely used as an Up to that point, most groundwater contaminants as co-metabolism, industrial degreaser for TCE was disposed of in a in the United States. It is digestive enzymes cleaning metals and as a fairly haphazard manner. also found at most DOE dry-cleaning agent until it "For years," says Steve sites, including the Oak produced by certain . . was classified as a Herbes of the Ridge K-25 Site. mzcroorganzsms are hazardous waste by the Environmental Sciences Researchers in ORNL's applied to the task of Resource Conservation Division, "practically every Environmental Sciences and degrading and Recovery Act (RCRA) metal machining shop, Chemical Technology contaminants, such of 1976. automotive repair shop, and divisions are testing two Because RCRA dry cleaner in the country innovative biological as TCE." regulations greatly used TCE, and many of techniques for removing increased the costs of them disposed of it TCE from groundwater. In a disposing of TCE, most improperly when they were process known as co­ uses of the chemical were done with it." As a result, metabolism, digestive enzymes produced by certain microorganisms are applied to the task of degrading contaminants, such as TCE. "Under natural anaerobic (oxygen-free) conditions, such as those found in groundwater, TCE degrades to vinyl chloride, an even more toxic compound," says Herbes. "Our goal for co­ Bench-scale bioreactors were used to demonstrate metabolic remediation is to the feasibility of co­ encourage degradation of metabolism as a TCE along pathways that remediation technique and to evaluate various result in less harmful methanotrophs gathered products. " from groundwater Two basic groups of contaminated with TCE at the Oak Ridge K-25 Site and microorganisms are involved DOE's Kansas City Plant. in co-metabolism of

70 Oak Ridge National Laboratory REVIEW A co-metabolism demonstration project is currently under way at the Oak Ridge K-25 Site using a specially modified bioreactor on loan from the U. S. Air Force Civil Engineering Support Agency. The goal of the project is to treat seepage from a series of pits used in the 1980s for the disposal of a variety of organic compounds, including TCE.

groundwater contaminants. To prove the usefulness 2.13 m (7 ft) tall and 40 em project. Before the water The first is methano- of this technology, the (16 in.) in diameter and are can be pumped into the trophs-bacteria that live project team is filled with polypropylene bioreactor, however, it must on methane. The enzymes demonstrating the co- support material for the pass through an air these bacteria produce to metabolism process at the cultures to grow on. A oxidation system to digest methane can also K-25 Site with the support control system is mounted decrease its iron content metabolize TCE. When of DOE's Environmental with the columns on a because the high level of methane and TCE- Restoration and Waste portable platform, which is iron in the seepage would contaminated water are Management Program's housed in a trailer at the eventually fou l the added to a bioreactor Office of Technology K-25 Site. The goal of the bioreattor system. As the containing methanotrophic Development. The heart of project is to treat seepage seepage passes through bacteria, their digestive the project is a specially from a series of pits used in and out of the bioreactor, it enzymes break down both modified bioreactor, on the 1980s for the disposal is collected in a storage the methane and the TCE. loan from the U. S. Air of a variety of organic tank that is periodically The TCE is first broken Force Civil Engineering compounds, including TCE. emptied at K-25's Central down into TCE epoxide and Support Agency, that The drainage from these Neutralization Facility. then into other products houses methanotrophic pits amounts to several Bench-scale bioreactors, that can be further bacteria cultures. The liters per minute, a fraction developed by Terry degraded by normal bioreactor consists of two of which is diverted for use Donaldson and Jerry biological processes. reactor columns that are in the demonstration Strandberg of ORNL's

Number Two, 1992 71 Technologies

Chemical Technology bacteria that consume containing a mixture of Division, were first used to toluene or phenol. Herbes organic contaminants similar demonstrate the feasibility and his project team have to that at the K-25 Site. of this technology and to been working closely with a A field test of this evaluate various private biotechnology firm technology is planned for methanotrophs. The to develop a culturing and the K-25 Site for the "In initial bench- cultures selected for use in bioreactor system for summer of 1992. "At the end scale tests, this the K-25 demonstration determining the feasibility of this test," says Herbes, process removed up project were evaluated on of employing these bacteria "we will have data that to 80% of the TCE the basis of their stability in a bioremediation system. provide a head-to-head and level of activity over Like their methanotrophic comparison of the two most from simulated time. Of the three cultures cousins, these bacteria promising techniques for the groundwater." finally selected, one was produce enzymes that bioremediation of TCE in from groundwater at the metabolize TCE as a side- groundwater. There are K-25 Site and two were effect of their normal many possible applications from DOE's Kansas City metabolic processes. within the DOE system for Plant. In initial bench-scale this technology. It could be The second group of tests, this process removed scaled up and used as the microorganisms involved in up to 80% of the TCE from treatment of choice at K-25 co-metabolic research is simulated groundwater or other DOE sites."

72 Oak Ridge National Laboratory REVIEW Bioluminescent Bacteria: Another Bright Idea·

S ince petroleum-eating up environmental contam­ researchers at ORNL and microbes were used to help ination. the University of scour the beaches of But do you ever wonder Tennessee are addressing Alaska's Prince William if there's a way to tell if as they develop a new Sound in the aftermath of these critters are eating or technology to monitor the the Exxon Valdez oil spill, not? Or if they're efficiency of micro­ "ORNL researchers the world has gotten used undernourished? Or too hot organisms in cleaning up have been developing to the idea of using to work? These are some soil and groundwater. microscopic "bugs" to clean of the questions that In a project originally bioluminescent sponsored by the sensor technology to Laboratory Director's monitor bacteria as Research and they digest soil and Development Fund, ORNL groundwater researchers have been developing bioluminescent contaminants." sensor technology to monitor bacteria as they digest soil and groundwater contaminants, converting them to relatively harmless substances, such as water and carbon dioxide. Bioluminescent sensor technology is a method for detecting the light emitted in the visible range by To determine the optimum genetically engineered diet for a colony of bioluminescent bacteria, bacteria that luminesce nutrients are added or taken during metabolism of away, based on the colony's certain types of chemicals. light level-the more light Robert Burlage of the given off, the more nutrients the bacteria are Environmental Sciences metabolizing. This Division (ESD) started luminescence, which is too experimenting with the dim to be seen in normal room light, is measured by bioluminescent, or "lux," precision light-sensing genes while working with equipment.

Number Two, 1992 73 Technologies

Gary Sayler in the lightning bugs and other Palumbo. "Depending on the University of Tennessee's insects. light level, we add or Microbiology Department, Once the lux gene was withhold nutrients as where most of the initial isolated, researchers necessary." To respond to "Researchers are work on the gene was incorporated it into genes the bacterial culture's also developing done. Burlage and his from common soil and specific nutritional needs, collaborator Tony Palumbo, water bacteria that are researchers are also strains of bacteria also of ESD, continue to activated in the presence of developing strains of that light up when the collaborate with the toluene, a component of bacteria that light up when culture is lacking a university group with whom gasoline and other the culture is lacking a particular nutrient." they share "constructs"- solvents, and use it to particular nutrient, such as combinations of the lux indicate degradation of nitrogen or phosphorus. genes. trichloroethylene (TCE), Almost all DOE sites have The lux genes were a common industrial problems with toluene, TCE, originally taken from degreaser. This or other types of bioluminescent bacteria combination of genes contamination resulting from that live symbiotically with causes the genetically disposal or spills of gasoline several species of deep- altered bacteria to light up and various chemicals used sea fish. It is theorized that, when they metabolize in research labs. A variety of because the bacteria are toluene or TCE. As a result, bacteria will be needed to also a food source for researchers can monitor metabolize the potpourri of smaller fish, they are used the rate at which the chemical wastes at some by the larger fish as a sort bacteria are metabolizing sites because each strain of of "bait" to lure the small the TCE by measuring the bacteria eats on ly certain fish into attack range. This amount of light they give types of waste. Because type of bioluminescence is off. these bacteria light up similar to that found in "It also gives us a way to selectively, they can also be control their activity," says used to identify the types of

74 Oak Ridge National Laboratory REVIEW contamination present at "To determine the containment system that the site. optimum conditions for a will enable researchers to "When we look at a site bacterial culture," says lower a bioluminescent we ask two questions," Palumbo, "you can either bacteria culture into a well Burlage says. "Does it have take all the nutrients away to monitor groundwater. To bacteria that can handle and add them back one at prevent release of bioremediation? The a time until you see an genetically engineered answer is usually yes. improvement or you can bacteria into the Once the lux gene is added look at the soil chemistry environment, the system to these bacteria, the next and add things that you will include a container that "The culture's question is, 'Are the genes think are missing." The admits groundwater without response ts that control the digestion of culture's response is letting the bacteria escape. contaminants turned on?'" determined by its light This type of apparatus determined by its If the genes are not turned level-the more light, the would be used primarily as light level-the more on, causing them to turn on more the bacteria are a continuous monitor for light, the more the may be as simple as metabolizing. This waterborne contaminants; bacteria are adding nutrients or as luminescence, too dim to however, some of the same metabolizing." difficult as identifying other be seen in normal room technology also could be environmental factors that light, is measured by used for soil sampling. They adversely affect the precision light-sensing expect to have a prototype bacteria. For example, one equipment. system working by the end of the current challenges Palumbo and Burlage's of the summer of 1992. facing Palumbo and latest refinement of the "The applications of this Burlage is developing a system is a cooperative technology are construct that remains effort with Tuan Vo-Dinh of widespread," says Burlage. active above 37°C, the the Health and Safety "The only things that limit us temperature at which the Research Division to are our imagination and current construct turns off. develop a fiber-optic knowledge."

Number Two, 1992 75 Technologies creentng e o pee s Search for Waste Eaters

S o many bacteria and his colleagues spent about purple may result-the so little time. That was the three months developing more contaminant that is problem faced by and testing a new metabolized, the deeper researchers in ORNL's procedure for rapidly the color. A "control" group Environmental Sciences identifying waste-eating of plates is incubated in Division (ESD) when asked bacteria. ordinary air to ensure that to evaluate the ability of The procedure uses any changes in the "This increase in thousands of bacteria palm-size plates containing experimental plates are efficiency has samples to metabolize 96 em-deep cells that are caused solely by the enabledESD environmental filled with bacteria, water, contaminants. contaminants common to and a dye that is sensitive When the incubation is researchers to many DOE sites. to the bacteria's metabolic complete, the plates are evaluate 10 times as At the time, standard processes. The plates, placed in a spectra- many samples as diagnostic tests involved along with a beaker of a photometer that shines a would have been culturing each strain of contaminant-usually light through each cell, possible using bacteria in a separate toluene, xylene, or carbon measuring its depth of container, adding a tetrachloride-are place in color, or optical standard methods." contaminant, and a dessicator and allowed to absorbance. These measuring the breakdown incubate for 24 to 48 hours. readings are then of the contaminant with a The contaminant translated into computer gas chromatograph. This evaporates into the air data. Only the bacterial process was time- insid~ the dessicator and is strains in those cell consuming and produced a eventually absorbed by the showing high levels of fairly large amount of waste water in the cells. metabolic activity are requiring special handling As the contaminant is required to undergo more and disposal. absorbed, those bacteria definitive gas "The volume of testing that are able to metabolize chromatography (GC) requested by DOE's it remove carbon from its testing. "With the old Subsurface Science atomic structure. This method, every strain would Program was more than we action frees hydrogen undergo GC testing," says could handle using atoms, which react with the Palumbo. "Using the standard methods," says dye, changing its color from screening procedure, only ESD researcher T any clear to purple. Because one in 50 is tested." This Palumbo. So-necessity not all bacteria metabolize increase in efficiency has being the mother of the contaminant equally enabled ESD researchers invention-Palumbo and well, many shades of to evaluate 10 times as

76 Oak Ridge National Laboratory REVIEW A spectrophotometer is used to screen contaminant· enriched bacterial cultures. Only one in every 50 cultures exhibits enough metabolic activity to require more definitive gas chromatography testing.

many samples as would known as agar, which many of the same have been possible using provides the general types techniques. This work, standard methods. Also, of nutrients needed to keep funded by DOE's Office of the amount of waste bacterial colonies alive. To Technology Development, generated by the screening increase the chances of involves finding bacteria process is 10 to 50 times isolating useful organisms, that metabolize chelators- less than that produced by the ORNL bacteria are compounds that attach standard methods. cultured in a contaminant- themselves to Palumbo and his group enriched environment, radionuclides, preventing are using this technique to enabling contaminant- them from reacting with study bacteria gathered degrading organisms to other elements in the through DOE's Subsurface thrive. "We're getting very environment and allowing Science Program from good results using this them to move more freely contaminated areas at the process," Palumbo says. through soil and Savannah River Site, Idaho Palumbo indicates that groundwater. Because National Engineering the Subsurface Science chelators are used to clean Laboratory (INEL), and Program may be sampling radionuclide-contaminated Pacific Northwest National bacteria sometime this year equipment, they have often Laboratory, as well as from ORNL's Melton been disposed of along bacteria gathered at ORNL Branch area as part of its with radionuclides. by ESD researchers. The ongoing study of diversity Chelator-metabolizing bacteria received from the in bacterial communities. bacteria would be useful in Subsurface Science ESD researchers are slowing or stopping the Program are cultured on also working with INEL on migration of radioactive the surface of a substance a related project using contaminants.

Number Two, 1992 77 Technologies as e- 1g 1ng onsor 1um o Bacteria Found in Amoebas

Researchers in ORNL's knack tor bioremediation of metabolizes the methanol, Health and Safety hazardous wastes. making formic acid, and so Research Division "The well was primarily on. Most significantly, the (HASRD) spend a fair contaminated with the consortia can be maintained amount of time studying the industrial solvent on mineral salts in a effect of amoebas living in trichloroethylene (TCE)" methane and carbon dioxide ORNL's cooling towers and says Arpad Vass of atmospher~an other warm water systems HASRD, "so we looked tor environment that will not While studying around the Lab. organisms in the well that support most of the bacteria amoebas from a well The reason tor all this could metabolize TCE. individually." on the Oak Ridge attention is simpl~n their Because we knew that In addition to the TCE- Reservation, travels, amoebas pick up a some methanotrophic degrading bacteria, lot of bacterial hitchhikers, researchers have bacteria-those that live on researchers have also which can cause illnesses methan~egrade TCE, identified bacteria that found groups of in humans ranging from we took amoebas from the produce biodispersants microorganisms with minor infections to well and put them in a (compounds that break up oil a knackfor tuberculosis and methane atmosphere. In and other organic bioremediation of Legionnaires disease. this environment, 20 contaminants) as well as These bacteria are hazardous wastes. different bacteria were others that metabolize particularly hard to isolated from within the creosote and trinitrotoluene eliminate because they live amoebas, one of which was (TNT). inside the amoebas, an able to degrade TCE. This A number of applications arrangement known as a is one of the most, it not the have been proposed tor consortium, giving the most, complex microbial members of this unusually bacteria an extra layer of consortium known in the versatile group of defense against world." microorganisms. The first environmental stresses, Vass says no one is sure field test tor the such as toxic compounds why these consortia occur, biodispersants will come this and changes in water but a high degree of summer at DOE's Savannah temperature or pH. interdependence River Site (SRS) where a While studying amoebas apparently exists among large amount of creosote- found in a well on the Oak the organisms. "The theory contaminated lumber has Ridge Reservation , is," says Vass, "that one of been stockpiled over the researchers have found the organisms metabolizes years. Because creosote, a consortia made up of methane making methanol. wood preservative used on microorganisms with a In turn, another railroad ties, telephone

78 Oak Ridge National Laboratory REVIEW poles, etc., is both a toxin and a mutagen, SRS Both of these test tubes personnel have been contain gasoline and water. searching for an Biodispersants break up environmentally acceptable solvents, such as gasoline, Into tiny droplets, known as way to dispose of it. The a mlcroernulsion (in the ability of biodispersants to container on the right). This remove contaminants from process dramatically Increases the surface area substrates like wood, rock, of the solvents, allowing or soil prior to biode­ them to be more easily gradation makes them ideal metabolized by bacteria. candidates for this job. When mixed in relatively eating bacteria from both Another combination of says Vass, "but since we low concentrations (1-2%) ORNL and SRS. It is hoped biodispersant and bacteria found this consortium, with compounds such as that the results of these has developed a taste for we've been broadening our creosote, oil, or solvents, experiments will confirm TNT, first removing the interests and, at the same the biodispersant breaks laboratory results supporting explosive from its soil or time, helping the these substances into tiny the effectiveness of water substrate and then environment." droplets, known as a bioremediation of creosote breaking it down into microemulsion, dramatically contamination. harmless components. This increasing their surface Other applications for process has shown a area. Once a compound is biodispersantlbacteria potential for removing soil separated from its substrate combinations include and water contamination in this manner, it can be secondary oil recovery. around munitions plants more efficiently degraded by When an oil well has been and storage facilities-so other microorganisms. Also, pumped "dry" using much potential, in fact, that using microemulsions of conventional methods, it is it has been licensed to Oak solvents for various often abandoned because Ridge-based EODT industrial processes could of the high cost of retrieving Services, a company potentially decrease the the residual oil. It is specializing in cleaning up amount of solvent needed, hypothesized that pumping sites contaminated with reducing the amount of biodispersant-laden water explosives-related waste. waste produced. into these wells could "Historically, our interest Biodispersant-producing loosen the oil from its rock in amoebas has been bacteria will be field tested substrate and allow it to be pathogenic-related to its in conjunction with creosote- economically recovered. ability to transmit disease,"

Number Two, 1992 79 New Waste Technologies Waste Identification: Building a Better Ion Trap

N ormally, when soil, resulted in its use for for analyzing samples. (For water, or air sampling is several other purposes, more information on this done in the field, samples including "sniffing" air technique, see Review, are taken back to the lab, samples to detect organic No. 4 , 1991, p. 54.) processed, and analyzed. contaminants; detecting "People are primarily Hours or even days later, semivolatile pollutants, interested in the speed of toxins contained in the such as pesticides; and the system and the ability to '"Its immediate uses samples are identified. If directly analyzing body do the analysis in the field," are screening for the other work depends on fluids for commonly used says Guerin. With this presence or absence these test results, it waits, drugs, such as cocaine, system, checking a soil of certain chemicals too. codeine, and nicotine. sample for carcinogenic in the environment- Obviously, this is a "This technique is not solvents such as benzene is problem begging for a cost- expected to replace as simple as mixing the soil this avoids having to effective solution-a existing Environmental with distilled water, bubbling send samples off to system that can be used in Protection Agency helium through the mixture be analyzed at $500 a the field to provide rapid methods," says ACD's to remove the solvent, and shot-and repetitive identification of specific Mike Guerin. "Its routing the solvent- monitoring of specific toxins. immediate uses are containing off-gases into the Enter ORNL's Analytical screening for the presence ion trap for analysis. All of pollutants. Chemistry Division (ACD). or absence of certain this is accomplished in a ACD researchers have chemicals in the matter of a few minutes. developed a portable mass environment-this avoids Work on the system was spectrometry system for having to send samples off originally funded by the identifying organic toxins in to be analyzed at $500 a Department of Defense as a air, water, and soil samples shot-and repetitive method of quantifying in the field. It consistently monitoring of specific organic compounds used as outperforms conventional pollutants, as is done in nerve gases. "During the analytical methods, remedial action programs." course of this work, we quantifying toxins in as little Starting with a observed that this as two minutes down to the commercially available ion technology might be parts-per-billion level. trap mass spectrometer, applicable to environmental The system was Guerin and his group have studies," says Guerin. originally developed to developed a system to Further research proved the detect volatile organic introduce samples directly system's environmental solvents in soil and water, into the ion-trap and applications, and the cost of but its versatility has standardized procedures its continued development

80 Oak Ridge National Laboratory REVIEW is now underwritten by both DOE's Office of Technology Development and the U.S. Army's Toxic and Hazardous Materials Agency. In September 1991, the The direct-sampling ion trap first field trial for the system mass spectrometer's portability allows was held at DOE's Volatile researchers to detect the Organic Compounds in presence or absence of Non-arid Soils Integrated certain chemicals in the field. Both time and money Demonstration test site at are saved by eliminating the the Savannah River Site, a need to send samples to a proving ground that has laboratory for analysis. horizontal well setups to demonstrate gas extraction and bioremediation As a result of their calibrating the system using at ORNL when their field technologies. The trial was success at the test site, pure compounds to monitor indicated a high highly successful and led to Guerin's group has received determine its sensitivity and level of organic a second trial in March. funding from DOE's Office durability. The current contaminants. They also During the March trial, of Technology Development system is about the size of noticed a strong odor and a Marc Wise and Cyril to build another system for a two-drawer filing cabinet hole in the bottom of the Thompson, both of ACD, the Savannah River Site and is mounted on a shock- tank. used a more portable and train their people to use absorbing base, so up to "They brought us some version of the system to it. "We want to know two of the units can be air and soil samples to monitor volatile organic whether people who have transported into the field in analyze," Guerin recalls, chemicals in the not been involved in the a van. Also, an even "and we had preliminary headspace of a development of this smaller version of the results for them within groundwater well and in the technology can be trained to system is in the works. minutes-even before they waste stream of a soil use it," says Guerin. "We Guerin is encouraged by were back in their office. remediation process known also want to see what kind the success of a recent They were pleased with as steam stripping. Also, of problems the system will unplanned test of the that kind of response. groundwater samples were encounter if it is used system. In March 1992, an Typically emergency analyzed in the field at a intensively." environmental remediation response in this business rate of 20 samples per Guerin and his group are group was pulling a tank takes from several hours to hour. in the process of testing and out of a waste burial ground as much as a day."

Number Two, 1992 81 New Waste Technologies Fiber-Optic Probe Sheds New Light on Groundwater Contaminants

O ne of the problems equipment that "sniffs" the the accessibility problem facing researchers air in the well to identify the and a few more problems interested in measuring substances dissolved in the besides. "To my knowledge," groundwater contamination water. says Haas, "this is the first is a lack of accessibility. The new and improved fiber -optic spectroscopic Groundwater is usually Derivative Ultraviolet device designed to identify "To my knowledge," sampled by either lowering Absorption Spectrometer and measure volatile says Haas, "this is a collection device down a (DUVAS ) system, aromatic compounds directly the first fiber-optic well, taking a sample, and developed by John Haas of in the groundwater." spectroscopic device pulling it back up for the Health and Safety Why direct sampling? analysis or by using Research Division, solves By detecting and measuring designed to identify the concentration of and measure volatile groundwater contaminants aromatic compounds directly, rather than by directly in the "sniffing" the air above the groundwater." water, the DUVAS system is able to more accurately BENZENE characterize groundwater contamination and avoid problems posed by air sampling. "For example," says Haas, "because some chlorinated hydrocarbons are heavier than water, they could go undetected by air The DUVAS system sampling above deep measures the amount of aquifers." light absorbed by the sample across a range of Direct sampling also wavelengths, producing an JET FUEL enables researchers to use absorption spectrum. a technique known as depth Individual compounds can profiling-analyzing be identified by their characteristic spectra. In groundwater samples from this example, the spectra for various depths. Depth benzene and toluene, the 230 260 290 profiling provides a more primary components of jet WAVELENGTH (nm) fuel, are combined in Its accurate assessment of absorption spectrum. contamination by

82 Oak Ridge National Laboratory REVIEW considering the possibility from imported oil with coal- sensitivity to these of varying concentrations and shale-based chemicals makes it at different depths, rather alternatives. DUVAS was especially adept at than relying on a single designed to "sniff" air detecting the first signs of measurement. samples at synthetic fuel groundwater Other advantages of production plants to detect contamination. using the DUVAS system carcinogenic vapors. The The system is well suited for groundwater analysis technology is now being for several applications, are that it offers applied to the detection of including monitoring • Rapid analysis of aromatic hydrocarbons in groundwater around "DUVAS was groundwater groundwater. underground fuel storage designed to 'sniff' air contaminants in the field. Aromatic compounds are tanks or disposal areas The system conducts a a particularly important where solvents, such as samples at synthetic complete spectral analysis class of chemicals because benzene, are buried; fuel production in less than a minute. of their presence in fuels monitoring manufacturing plants to detect • Increased safety. (benzene and toluene) and discharges or chemical carcinogenic Because groundwater their use in the spills in surface water; and vapors." samples are not removed manufacture of paper monitoring reagent from the well, workers are (phenol) and insulators concentrations in chemical not exposed to chemical (polychlorinated biphenyls, process streams. and radioactive or PCBs). They are also Over the past three contamination. widely used as solvents, years, Haas has received • No chain of custody for dyes, and explosives. funding to update the samples and no storage Topping the list of organic DUVAS system and to concerns. chemicals most commonly develop a new fiber-optic • Direct measurement of found at DOE sites, sampling probe. The groundwater including ORNL, are updated system is contamination, making volatile aromatics, such as computer controlled, possible continuous benzene and toluene, battery powered, and, at monitoring. which are among the most about 9 kg (20 lb), it is New applications. migratory components of completely portable. DUVAS was originally fuels contaminating Now that this phase of developed in the early groundwater. As a result, his research is complete, 1980sin responsetothe they are usually found Haas is field testing the push in the United States farthest from the source of system at Lawrence to replace fuels refined contamination. DUVAS' Livermore National

83 New Waste Technologies

ORNL-DWG 92M-7971

Laboratory's technology that enters the sample and demonstration site where the light that passes about 68,000 L (17,000 gal) through can be measured. of gasoline have been That difference is attributed spilled. There DUVAS will to absorbed light. be used to monitor the Measuring the amount of effectiveness of a absorbed light at many remediation process known different wavelengths as dynamic underground produces an absorption stripping. This technique spectrum. Because uses a combination of individual compounds Probe components include steam injection and absorb light at an optical fiber (A), a garden hose used as a sheath for electrodes to heat characteristic wavelengths, the fiber (B), an adjustable contaminated soil, turning the presence of each chuck to hold and position water in the soil to steam chemical is indicated by its the fiber (C), a lens to focus light Into the detector (D), a that drives out volatile absorption spectrum. sampling region where the contaminants. The ability of The system operates by sample Is collected (E), a the DUVAS system to generating ultraviolet light quartz window between the provide continuous in the range from 230 nm sample and the detector (F), a photodlode detector (G), monitoring of the process in to 350 nm and transmitting and a cable to provide underground wells at the that light through an optical power to the detector and site will help researchers fiber to a submerged carry data to the computer (H). determine the effectiveness probe. Ultraviolet light is of the process and used because it is optimum conditions for absorbed well by aromatic "steam cleaning" gasoline compounds. contamination out of the When the light reaches soil. the probe, it is focused How it works. DUVAS is through the groundwater a spectroscopic technique sample onto the detector. based on the principle that The probe is fitted with a_ virtually all molecules pump and a filter to ensure absorb light. When light is that water samples are free shone on a groundwater of dirt and other particulate sample, the difference matter. Because ultraviolet between the amount of light light is not conducted well

84 Oak Ridge National Laboratory REVIEW ... C:, ..

. . <:> . · ~ ·. :o ·o .·

Typically, the DUVAS fiber­ optic probe is lowered down a well, where It collects and analyzes a groundwater sample and transmits the resulting information to a computer on the surface.

by optical fiber, Haas such as benzene, can be system to accommodate incorporated a detector into measured to as low as 100 analysis of contaminant the probe and added an parts per billion. Strong vapors in subsurface soil electronic feedback loop, absorbers, such as gas is also being rather than using an optical polynuclear aromatics, considered. fiber to transmit light from some of which are potent the probe back to a carcinogens, can be detector on the surface. As detected at parts-per-trillion a result, the required length levels. The system's of the optic fiber is reduced analysis of contaminant by half, allowing the probe concentrations is typically to be used in wells as deep accurate to within 1%. as 50 m. The information Future enhancements of gathered by the detector is the DUVAS system include then transmitted back to coupling the probe with a the surface where it is camera to examine analyzed by a laptop phenomena such as high­ computer. velocity contaminant jets Concentrations of entering a well through chemicals that absorb small cracks in the well ultraviolet light weakly, casing. Modifying the

Number Two, 1992 85 Technologies aser ystem tzes p erna Waste Problem

D OE's Fernald Feed 1995 as part of the Fernald range cameras to map Materials Production Environmental Management three-dimensional robot Center had a problem. In Project. Until then DOE and environments saw that this 1951 , four domed storage EPA agreed to suppress technology could be used silos were built, and two of radon emissions by putting to build a three-dimensional them were filled with foot-thick bentonite clay surface map of the waste radium-rich uranium ore caps over the waste in the before and after the residue, a by-product of two silos. These caps bentonite was applied . A uranium processing at the contain the radioactive gas comparison of these The highly accurate site. until it decays into non- measurements would verify data on the waste's The ore was originally gaseous elements that are that the bentonite seal was surface features stored in the four-story-tall trapped in the bentonite. at least a foot thick. Having saved 15 to 25 silos for use in commercial The deadline for putting the accurate information about million dollars. processes, such as cap in place was December the surface of the waste producing luminous paint 1991. would also keep the for watch and instrument In December 1990, Barry amount of bentonite used dials. However, before the Burks of ORNL's Robotics to a minimum. This was radium could be recovered, and Process Systems especially desirable given its health hazards were Division attended a meeting that the contents of the discovered, and the ore at Fernald on how robotic silos, both the ore residue was reclassified as waste. technology could be used to and the bentonite, would be Four decades later, this help meet remediation removed and treated prior material is still sitting in needs at the site. During a to permanent storage, aging silos 20 m (60 ft) coffee break, Burks talked beginning in 1995. above the largest aquifer in with a representative from Burks suggested the the Midwest, and the Parsons Engineering, one surface-mapping technique decaying radium continued of the contractors to the group, and in to generate large amounts remediating the site. January 1991 , this of radioactive radon gas. Parsons was looking for a approach was officially Under terms of a 1990 way to ensure that the clay adopted. Only 9 months agreement between DOE cap they were preparing to were left for the system to and the Environmental install was at least a foot be developed, tested, and Protection Agency (EPA), thick over the entire surface used to map the surface of the ore residue is of the waste. the wasteforms before the scheduled to be removed ORNL engineers who clay seal was scheduled to from the silos beginning in had previously used laser be applied in October. "By the time we figured out what eq·uipment we needed and began detailed design, it was May," says Burks, "and we had to have the system working by the end of July, so we could test it The storage silos at DOE's Fernald Feed Materials at Fernald in August." Production Center were built Several ORNL groups in 1951 to temporarily store helped Burks' group meet radium-rich uranium ore. the deadline. "The Plant Discovery of the health hazards associated with and Equipment Division radium prolonged this stay helped us when we by several decades. urgently needed fabrication work done," says Burks, wearing respiratory Dinkins conducted a cold "and the Finance and equipment and three pairs test (a test in a Materials Division gave us of gloves, before entering nonradioactive a warehouse where we the restricted area around environment) of the roped off an area 24 m the silo. This kind of field system's performance in an (80 ft) in diameter to use as work was a new experience empty silo at Fernald. It a mock storage silo. Then for many of us who were performed beyond we set our equipment up used to laboratory requirements, measuring on stands to simulate conditions," says Burks. the height of a 0.3-m conditions at Fernald." Other trying conditions (1-ft) tall calibration target Despite all the included evacuations of the to within 0.64 em (0.25 in.) simulations, conditions at area several times a day of its actual height with a Fernald were not what because of high radon variation of less than Burks and his group were concentrations, poor 0.25 em (0.1 0 in.) between used to. Protective clothing weather, and high winds repeated measurements. was required, even in the that prevented workers Also during the cold test, control area, and when from reaching the access an alignment and repairs had to be made, the doors, called "manways," calibration scheme was task fell to the ORNL located on top of the silos. developed that was a major researchers. "One of our In August 1991 , Burks factor in the success of the guys had to dress out and colleagues John Rowe, measurements. "The tests completely, including Fred DePiero, and Marion demonstrated the superior

Number Two, 1992 87 New Waste Technologies

was a backup) and rotated them among the silo's manways to obtain a complete surface map. Maps were built up a section at a time using an infrared laser equipped with Workers installing the system In the silo access a cylindrical lens to project doors used protective a line on the surface of the clothing and respiratory waste. A high-resolution, equipment to guard against high concentrations of black-and-white video radon gas in and aroun~ the camera was used to record storage silos. ... an image of the line. "In one image, you can accuracy and reliability of data. In response, the get up to 50 to 60 data the measurement system," group developed a piece of points on the surface being says Burks. "Practicing menu-driven software scanned, each several installing the system in an which enabled the user to inches apart," says Burks. empty silo also helped us calculate, set, and change "Thousands of images determine the tools we system parameters as were acquired and needed to do the job. When often as necessary. "This analyzed to map each silo." you're working in a cut down on the time it took an image-processing contaminated environment, to gather data," says Burks. system digitized each you don't want to stop "It also allowed us to image and fed it into a halfway through the specify a series of lines for computer that performed installation and go get a the system to scan and high-speed geometric tool." then leave the computer to transformations on the Before the cold test, the run the system at night or processed image to project team had focused when high radon levels determine the location of on system function and forced evacuation of the the line in space. The accuracy. The test control area." results of these calculations successfully demonstrated To map the large, were then fed to a the system's performance, irregular waste surfaces workstation where they but it also highlighted the inside the silos, Burks and were displayed for the need to increase its rate of his group used three operator. From the gathering and processing camera-laser units (one workstation, the operator

88 Oak Ridge National Laboratory REVIEW could control system the new software and because it eliminated the parameters, such as the techniques developed over need to buy and apply starting and ending points the course of their work at thousands of extra cubic of regions to be scanned Fernald, Burks' group feet of bentonite. It also and various image analysis scanned the final silo in made it unnecessary to parameters. only 47 hours, enabling retrieve and treat the Mapping the entire them to finish taking data excess radon-contaminated surface of the waste on October 11--one day clay that would have been required that it be surveyed ahead of schedule. The applied if Burks' surface from several different bentonite caps were data had not been perspectives. Each silo has applied by Thanksgiving, available. "It cost about five manways, one in the and mapping of those $700,000 to develop the center of the dome and four surfaces was finished in system and about around the perimeter; data late December. $300,000 to put it in place," were gathered using the "The people at Fernald says Burks, "The savings measurement unit in the were happy to get the have been estimated at center manway in results," Burks says. "The 15 to 25 million dollars. conjunction with units surface features of the That's a good return on an located in each of the waste were different from investment by any perimeter manways. A what they expected, and measure." frame of reference was that made a big difference established by placing in the amount of bentonite lights in sounding ports they applied and how they along the edges of the applied it. Various domes, several feet above scenarios called for the the waste. As a result, application of up to maps of surface features 3000 m3 (80,000 ft3) of the before and after the clay sealant. Using our application of the bentonite data on surface features, could be compared, they met DOE-EPA verifying that the entire requirements using only waste surface had been about 900m3 (24,000 ft3). " covered to the required The highly accurate data depth. on the waste's surface The cold-test silo took features resulted in two weeks to scan. Using considerable cost savings

Number Two, 1992 89 New Waste Technologies Microwaves Chip Away at Contaminated Concrete Problem

W y. you might ask, concrete tainted with contamination in the would anyone want to contaminants, such as concrete must be reduced "We expect the develop new ways to clean uranium or polychlorinated to safe levels. process to be faster concrete? biphenyls, is a common Using a microwave than conventional Well, for starters, there problem at nearly every generator originally are over 200 acres of DOE laboratory or developed for fusion technologies when it radiation- and hazardous production plant. Before energy research , Terry is fully developed." waste-contaminated these areas can be used White of the Fusion Energy concrete under roof at the for other purposes or Division has developed a Oak Ridge K-25 Site, and demolished, the method of decontamination

Microwave heating of concrete avoids many of the problems of conventional decontamination methods. It creates chips that are small enough to be removed by a vacuum system, but too large to create an airborne contamination hazard; it is a dry process, eliminating problems with soluble contaminants; and, because no external impacts are required to remove the surface, contamination is not driven farther into the concrete.

90 Oak Ridge National Laboratory REVIEW Phase ll Mobile Microwave Concrete Decontamination Prototype

CONTROLS AND POWER SUPPLIES

480 v 3q, 100 kVA 76 Umin WATER MICROWAVE TUBE WAVEGUIDE SYSTEM A more powerful mobile 100 FT. CABLES VACUUM SYSTEM version of the microwave DRIVE SYSTEM decontamination system is expected to be completed by the end of this year. The ' .., system will be designed to remove concrete faster and in thinner layers. Testing of the new system is scheduled to begin in 1993.

that uses microwaves to surface is an effective form contamination, such as rapidly heat concrete of decontamination. uranyl nitrate, to soak into surfaces. The heat causes Several methods are the concrete. Also, the water present in the currently used to remove impact of the chisel can concrete to turn into steam, contamination from drive contamination farther generating internal concrete surfaces, but they into the concrete. pressure. This pressure all have shortcomings. High-pressure water can combines with the thermal Pneumatic chisels are used be used to blast stresses produced by rapid to chip away contaminated contamination tree, but the microwave heating to break surfaces, but this approach waste water must be the surface layer of generates a lot of dust, treated afterward to concrete into small chips. creating an airborne remove contaminants. Because the vast majority contamination hazard. The High-pressure water of contamination is dust can be minimized by cleaning also causes confined to the top several working on a wet surface, soluble contaminants to millimeters of the concrete, but the water causes penetrate farther into the removing the concrete's soluble forms of concrete.

Number Two, 1992 91 New Waste Technologies

40 I

35 t- -

30 t- - damage the system. 25 - During the course of the ~ r ~ experiments, detectors 1- ....___ :X: 20 - C) measure forward power, UJ ~ the amount of microwave 15 t- power applied to the Removal of contaminated 10 t- concrete; transmitted concrete using microwave power, the power passing heating solves the problem 5t- - through the concrete; and of airborne contamination. scattered power, power Less than 1% of the debris I ow that escapes around the created by this process is 0.1 10 small enough to pose an CONCRETE PARTICLE SIZE (mm) applicator. airborne contamination White's experimental hazard. setup consists of a stationary microwave generator, a waveguide A third approach has contamination hazard. As a system and applicator to been steel shot blasting, a result, the surface can be channel the microwaves surface-finishing kept dry, eliminating from the generator to the technology that creates a problems with soluble concrete, a concrete slab uniform finish by removing contaminants. This mounted on a roller and compacting surface approach also avoids the system used to slide it material. Its shortcomings problem of driving along beneath the as a decontamination contamination farther into waveguide applicator, and method are that it creates a the concrete because no a vacuum system to lot of dust, it is relatively external impacts are remove debris generated slow, and it also tends to required to remove the by the heating process. pound contaminants back surface. Two different into the concrete. In his initial research, microwave generators Microwave heating, on White simulated a mobile have been used in White's the other hand, solves the microwave heating system research-a dust problem by creating by sliding a concrete slab 6-kW, 2.45-GHz generator chips small enough to be under a stationary and a 10-kW, 10.6-GHz removed by a vacuum applicator. The applicator is generator-allowing him to system, but generally too designed to minimize control the depth of large to create an airborne reflected power so as not to concrete removal by

92 Oak Ridge National Laboratory REVIEW varying the frequency of thinner layers of concrete the microwave source. more efficiently. The Higher frequencies increases in frequency and concentrate more of their power, combined with energy near the surface of improvements in the the concrete and remove a applicator design to spread thinner layer of material. the microwaves over a Lower frequencies are larger area, are expected to absorbed deeper in the result in considerably concrete and, therefore, higher removal rates. remove a thicker layer. "A "We expect the process lot of microwave design is to be faster than based on intuition, conventional technologies experience, and trial and when it is fully developed," error," White says. "There says White. A mobile aren't many standards in microwave heating this kind of work." prototype is expected to be The next step will be to completed by the end of construct a 15-kW, 18-GHz this year, and testing will system designed to remove begin in 1993.

Number Two, 1992 93 License Renewal for Commercial Nuclear Power Plants

By Claud E. Pugh

ince the 1973 oil embargo, demand plants have offered several environmental for electricity in the United States has advantages over plants fired by fossil fuels, increased at a slower rate than historic­ including the absence of emissions of carbon demandS projections would have predicted for the dioxide (one of the greenhouse gases), sulfur economic growth of the past 18 years. dioxide (a possible cause of acid rain), and Nonetheless, the demand has increased by 60% nitrogen oxides (contributors to urban smog and over this time. Commercial nuclear power plants, acid rain). some of which have been operating since the Although nuclear energy has played an 1960s, have met a significant portion of this important role over the past three decades, it is increased demand. Today nuclear generating approaching a crossroads. One decision must be capacity in the United States totals over 100 made concerning the feasibility of building future gigawatts, representing over 20% of the nation's nuclear plants, and another must be made total capacity for generating electricity. In concerning the need to extend the operating life of addition to their energy contribution, U.S. nuclear existing nuclear plants. Although the most recent order for a commercial nuclear power plant in the United States Claud Pugh examines one of was placed in 1978, the many large­ the plants ordered scale vessels that before that year the Heavy-Section have continued to Steel Technology be completed and Program connected to the overpressurized nation's electrical until they grid. Today five fractured. These plants remain to be tests were done It by ORNL for the completed. is federal recognized that government to electric utilities confirm that the probably will not margins between order additional allowable nuclear plants operating unless regulatory conditions and requirements are conditions that restructured to could lead to pressure vessel reduce their fracture were complexity and the sufficiently large. time required for license approval and

94 Oak Ridge National Laboratory REVIEW construction. Progress is being made; however, DOE, the electric utility industry, the Nuclear Regulatory The capacity of Commission (NRC), and the Congress nuclear power §"" 100 are taking major steps toward e. plants to generate establishing designs, regulatory ui electricity in the ::) processes, and a legal framework for :!: United States has future nuclear plants. For example, in > 80 reached its u1- late May 1992 the U.S. House of ~ maximum and will c.. <[ decrease Representatives passed legislation u 60 a: dramatically after similar to a previously passed Senate ~ UJ ...J the year 2010 bill and similar to new NRC u :::> unless the procedures that will permit one-step z 40 0 licenses for these UJ licensing of nuclear power plants. ...J plants are ...J Concurrently, the industry and DOE ~ renewed. !ii 20 are working on designs for passive­ :!: water reactors and advanced reactor concepts to be certified by the NRC. Because licenses of the existing 1980 1990 2000 2010 2020 2030 plants are for 40 years, they will begin CALENDAR YEAR to expire at the end of the century, before the advanced nuclear plants can be available, even under the license- reform rules. Nonetheless, the United States is on will apply for license renewal. In addition to the verge of a significant increase in nuclear helping meet demand for electricity, renewal of power production capability, an increase that will licenses can lead to major economic savings. For be vital until advanced plants take their place in example, it has been estimated that if the licenses power generation. This increase is to come from were renewed for 20 years for all of the existing the renewal of the operating licenses for the nuclear plants, a savings of up to $200 billion existing nuclear plants. Instead of permanently could be realized. The principal reason is that the shutting down dozens of nuclear plants and utilities have amortized the capital cost of the removing an important source of electricity, the plants over the initial 40-year license period. NRC and utilities may extend their operating life Increased operating and maintenance costs for an 20 years. License renewal is the second most aging plant during a renewal period will be much important decision that must be made at the less than the capital investment required to build nuclear energy crossroads. new plants, nuclear or fossil. Additionally, the The figure here shows the rapid loss of nuclear economic infrastructure of the utility industry generating capacity that will occur after the year would experience significant relief if replacement 2010 if no additional plants are built or licenses of these plants were deferred by up to 20 years. extended. However, it is anticipated that up to Current federal regulations permit license 75% of the 112 existing plants, or some 80 plants, renewal, but they do not give guidance on the

Number Two, 1992 95 LICENSE RENEWAL FOR COMMERCIAL NUCLEAR POWER PLANTS

requirements. Anticipating that nuclear utilities • establish a program that can identify and would request renewal of plant licenses, the NRC monitor age-related degradation of SSCs began several years ago to establish regulatory throughout the renewal period; and policies, technical bases, and procedures • establish a program to demonstrate that the appropriate to license renewal. The NRC is now plant is in compliance with the CLB completing that process, and the regulatory bases throughout the renewal period. to approve these renewals and to oversee the plants during the renewal period are essentially all The CLB is composed of the original in place. For this effort, the NRC has drawn licensing requirements (e.g., codes, standards, heavily on ORNL to conduct supporting research. regulatory guides) plus requirements that have The regulatory requirements for license been added for the plant during its current renewal fall into two categories-technical and license period. Compliance with the CLB environmental. The NRC places such ensures that at least the current margins of safety requirements in the U.S. Code of Federal are maintained throughout the renewal period. Regulations. Plants seeking license renewal must One major emphasis for the NRC has been to satisfy review requirements both at the time identify exactly which parts of the plant should renewal is granted and during the renewal period. be required in the SSCs to avoid or mitigate the As in earlier phases of developing nuclear power, consequences of hypothetical accidents. ORNL has contributed significantly to both areas ORNL has been a major participant in by supplying data, analysis, and technical conducting research on the age-related interpretations to the NRC. The NRC require­ degradation of many of these structures and ments and some ofORNL's contributions are components. This work has included identifying presented below. degradation mechanisms, developing methods for monitoring degradation, evaluating Technical Requirements approaches (rules, criteria, and limits) for mitigating the effects of degradation, and The technical requirements for license renewal establishing technical bases for rules limiting the are based on two key principles: (1) the existing effects of aging. In particular, ORNL researchers current licensing basis (CLB) for each operating have addressed concrete structures, pressure reactor provides an acceptable level of safety for vessels, and engineered safety systems operation during the renewal term, and (2) each components. plant's licensing basis must be maintained during the renewal period, using existing or new Concrete Structures programs that focus on the management of age­ related degradation of plant systems, structures, Studied at ORNL and components (SSCs). Evaluators of a renewal The containment building and the basemat, on application will determine if the applicant has which the reactor sits, are the two most taken the required steps to important concrete structures in a nuclear power • document the CLB for that plant-that is, state plant in terms of safety. Material and structural all the codes, standards, and regulatory guides degradation resulting from aging and that apply to that specific plant; environmental influences must be understood and managed to ensure the integrity of these • identify the SSCs-safety equipment plus those components and the associated defense against components that may affect the performance of release of radiation to the environment. safety equipment; ORNL addresses concrete structures in the • complete an assessment of the plant to verify NRC-sponsored Structural Aging Program, led that it complies with the CLB at the beginning by Dan Naus and Barry Oland, both of the of the renewal period; Engineering Technology Division. The

96 Oak Ridge National Laboratory REVIEW program's chief goal is to establish technical bases for regulatory criteria, which will identify for license reviewers and licensees potential LARGE FL SPf"CIMEN structural safety issues and provide PRESSUf\'E TENSILE Sf INCREASE , John Merkle of acceptance criteria. WITH II\ ORNL researchers are studying the TEMPI the Engineering Technology aging and environmental influences on Division describes the properties of both concrete and to former NRC steel-reinforcing materials, potential Chairman Admiral degradation mechanisms, structural Kenneth Carr inspection and monitoring techniques, some of the repair methods, and procedures for ORNL material structural evaluations, especially of the specimen studies containment building and basemat. that have provided the The ORNL group has compiled bases for many of extensive information from domestic the ru les and and international sources for nuclear criteria for reactor and non-nuclear civil structures and pressure vessel research activities. The information is safety being compiled into comprehensive assessment. data bases on long-term material properties, concrete aging mechanisms, inspection, repair, and structural integrity experience. One important part of this effort is ORNL's development of a Structural Materials Information Center, which makes these data bases available in handbook and electronic formats. It will be an important Section Steel Technology (HSST) Program, has resource for assessing concrete structures during been the lead laboratory for this research for more license renewal evaluation. than 25 years. The principal factors of concern are Other developments include (1) an aging that vessels are subjected to active aging assessment methodology, which can be used to mechanisms, such as increasing embrittlement rank concrete structures in terms of safety caused by neutron radiation; can be potentially significance and resistance to environmental exposed to stresses, such as sudden decreases in damage, and (2) a methodology to assess the temperatures and pressures, under accident current condition and predict the lifetime reliability conditions; contain fabrication flaws; and cannot of concrete structures. Other guidelines on be easily replaced to extend the plant's life. inspection and repair will be issued by ORNL. Before the creation of the NRC, the Atomic Energy Commission (AEC) initiated research to Reactor Pressure Vessel obtain data and develop methods to ensure that adequate margins of safety existed for the thick­ Research at ORNL wall pressure vessels in commercial nuclear Reactor pressure vessel (RPV) research power plants. In 1966 ORNL was chosen to be the continues to receive high priority from the NRC lead laboratory for that research and has provided because of its importance to safe plant operation continuous support to the AEC and NRC. The and other factors. ORNL, through the Heavy- work has produced many of the methods that are

Number Two, 1992 97

William Pennell observes the interior of a full-size commercial reactor pressure vessel whose walls are 20 em (8 in.) thick.

incorporated in codes and standards used by the nuclear industry and the NRC, such as the reference fracture toughness procedures in the American Society of Mechanical Engineers (ASME) code and the NRC Regulatory Guide 1.154, which gives guidelines for evaluating RPV integrity under pressurized thermal-shock (PTS) scenarios in which a hot, pressurized, irradiated vessel is suddenly chilled by the introduction of cooling water. Current work on RPVs at ORNL consists of three programs: the HSST Program, managed by Bill Pennell of the Engineering Technology Division; the Heavy-Section Steel Irradiation (HSSI) Program, managed by Bill Corwin of the Metals and Ceramics Division; and the Surveillance Data Bases, Analysis, and Standardization Program, managed by Frank Kam of the Computing and Telecommunications Division. ORNL's leadership in these areas is recognized worldwide, and the ORNL staff maintain strong relationships with their counterparts in many countries and at the International Atomic Energy Agency.

Don Casada examines a worn gate valve similar to valves used in nuclear power plants.

99 LICENSE RENEWAL FOR COMMERCIAL NUCLEAR POWER PLANTS

The Yankee Rowe Plant was the oldest operating commercial nuclear power plant in the United States, and its license was scheduled to expire in the year 2000. This plant, which has a pressurized-water reactor, has an electric generating capacity of 167 MW. It was to be the first to apply for license renewal, but the utility recently retired the plant for economic reasons.

The fust sidebar to this article addresses the prescribed conditions. In this area, ORNL has HSST Program and some of the issues it developed a series of advanced data bases and examines. The HSST goal is to provide the NRC computer codes for use in making fracture with the best available technology to ensure predictions. margins of safety against fracture of the RPV ORNL researchers are continuing to conduct under hypothetical scenarios. The PTS scenario advanced studies of the fracture characteristics of has gained the most attention because it combines the materials, fracture behavior of structures, and the elements of fracture-prevention analysis, analytical methods applicable to complex material properties, fabrication factors, and aging structures. Careful performance of many large­ effects resulting from irradiation. scale fracture experiments and their supporting Mechanisms responsible for age-related analyses have defmed the validity of and margins degradation of pressure vessels include prolonged for the current RPV assessment methods. These radiation exposure, sustained pressure and thermal efforts now include a focus on conditions that loadings, and transient pressure and thermal would exist beyond the initial license period. loadings. Understanding these mechanisms and RPV life is based not exclusively on time, but the materials making up vessels is the key to rather mostly on the embrittlement of the RPV ensuring that a vessel will not rupture under steels, which depends on the amount, rate, and

100 Oak Ridge National Laboratory REVIEW temperature of neutron radiation. In other words, Material damage caused by thermal and mechanical the life-limiting conditions for a vessel depend on stress cycles over time results in degradation that the neutron exposure and the conditions under must be factored into the allowable life which it is accumulated. Of course, during the assessments. By knowing the plant's operating approved period of extended operation, the history, the owner can compute accumulated accumulated radiation exposure will be greater than damage resulting from thermal aging, fatigue, and for the plant's initial 40 years. Current limits on other factors to determine the remaining allowable allowable embrittlement are expected to apply in life for the vessel, as defined by the code criteria in principle during renewal periods, and the current the CLB. Thus, accurate records of a plant's research is aimed at verifying that these limits will operating and maintenance histories are recognized not be exceeded during a 20-year extension. With by utilities as important for license renewal. respect to monitoring RPV aging, one key need is Nanstad's group also continues to study the aging in-reactor surveillance programs that give accurate of these steels under long-term thermal exposure data on the neutron exposure and vessel conditions. embrittlement during operation. Frank Kam and his project team are working closely with the NRC to Engineered Safety Systems "ORNL improve surveillance programs by combining the researchers best available dosimetry techniques with the Components Studied at 0 RNL periodic testing of tensile and fracture specimens ORNL researchers are studying aging of nuclear are studying made of the RPV steel and weld materials that are reactor plant components, such as valves, pumps, aging of exposed to actual reactor operation. They also steam generators, and vessel internals. Because the maintain for the NRC a carefully documented condition of these aging SSCs must be considered nuclear national surveillance data base on which regulatory throughout license renewal periods, the research is reactor plant guidance for embrittlement assessments is based. focused on (1) developing guidelines for assessing components, If the calculated embrittlement for the vessel in a the condition of components at the end of the specific plant reaches the allowable limit, current license period, (2) devising methods for such as regulations permit the owner to thermally anneal the monitoring age-related degradation during the valves, vessel to remove a portion of the accumulated license renewal period, and (3) where possible, embrittlement. In work for the HSSI program, Bill identifying approaches to mitigate age-related pumps, Corwin and Randy Nanstad are verifying the correct degradation effects. steam times and temperatures for annealing to achieve For the past eight years, ORNL has been a lead generators, acceptable levels of recovery for vessel steel and laboratory for the NRC in this area and has made welds that may be more than 20 em some major breakthroughs, especially in developing and vessel (8 in.) thick. Their experiments on welds removed techniques for nonintrusive monitoring of valves. internals." from the vessel of the cancelled Midland Nuclear This work has led to patented techniques and Plant Unit No. 2 will determine the degree of substantial technology transfer to industry. Don recovery from annealing and reembrittlement rates Casada, the manager of this research, describes during subsequent radiations for prototypically these developments in the second sidebar to this thick welds. The HSSI Program staff are carefully article on p. 95. The research at ORNL is part of the combining these results with those from earlier and NRC's overall Nuclear Plant Aging Research smaller specimen studies to provide the NRC with Program. the best available basis for establishing annealing standards. The NRC is completing development of Environmental Effects a regulatory guide to permit utilities to anneal their RPVs and to continue operation after annealing A proposed NRC rule will cover environmental even under license renewal. effects that should be addressed during the process Radiation-induced embrittlement is not the only of license renewal. Over the past few years, a age-related degradation mechanism affecting RPVs. multidisciplinary team led by Rich McLean, Lance

Number Two, 1992 101 LICENSE RENEWAL FOR COMMERCIAL NUCLEAR POWER PLANTS

McCold, and Johnnie Cannon, all of the Energy The first application to renew a license for a Division, has intensively studied the potential boiling-water reactor is expected to come from environmental impacts of extended nuclear plant the Northern States Power Company (NSPC) for operation (see the interview on p. 114). The its Monticello Nuclear Power Plant, whose study identified more than 100 issues, made license is scheduled to expire in 2010. Both of detailed assessments of potential environmental these plants have in recent years been the focus impacts, and examined the relationships of the of advanced studies by DOE and the Electric issues to the National Environmental Policy Act Power Research Institute to assess the issues of (NEPA). The final goal was to identify the many aging and potential procedures for license issues that can be treated on a generic basis and renewal. The NSPC is expected to submit its the remaining few that must be handled on a application for license renewal in early 1993. plant-by-plant basis. The lead time between submittal of a renewal The results of the study were published for application and expiration of the initial license public comment in late 1991. The public­ period is expected to be about 15 years. About comment period recently ended, and ORNL is 5 years will be required to obtain approval for helping the NRC formulate responses. After the all aspects of the application, and the other NRC makes its fmal responses, this part of the 10 years are allowed for the plant owner to license extension rule will be complete. The provide an alternative source of electricity NRC will document the final rule as a should the application be denied or if the owner modification to Part 51 of Element 10 of the decides not to extend the plant's operation. The U.S. Code of Federal Regulations (10 CFR 51). license renewal is to become active when the approval is granted and to extend through the Implementing the renewal period. For example, if the renewal is approved 10 years before expiration of the initial License Renewal Process 40-year license, the renewal will cover the Upon completion of the generic remaining 10 years plus the approved renewal environmental impact statement for extending period. nuclear plant operation, all the regulatory In conclusion, meeting the growth in demand instruments will be in place to allow for electricity in the next several decades in the applications for license renewal. The first United States can be easier and less costly if the license renewal application was expected to be operating licenses of existing nuclear power for the pressurized-water reactor of the Yankee plants are renewed for another 20 years. ORNL Atomic Electric Company's (Y AEC) Yankee has played an important role by providing the Nuclear Power Station in Rowe, Massachusetts NRC with technical expertise, data, and analyses (see photo on p. 88). Commonly called Yankee on which to base regulatory criteria and Rowe, it was the oldest operating nuclear power guidelines for license renewal. The development plant in the United States, and its license was of the regulatory procedures is now essentially scheduled to expire in 2000. However, Y AEC complete. It is expected that ORNL will recently decided to retire this plant because of continue to contribute to the development of economic considerations, including the cost of nuclear power technologies, including the the extensive efforts that would have been advanced reactors that will be certified by the required to qualify its embrittled reactor vessel NRC for the next generation of nuclear power for continued service. plants.

102 Oak Ridge National Laboratory REVIEW Biographical Sketch

Claud E. Pugh has been director of the A native of North Carolina, he received his Nuclear Regulatory Commission (NRC) Ph.D. degree in engineering mechanics from Programs Office ofORNL since 1989. North Carolina State University. He has Since joining the ORNL staff in 1968, he served on that university's faculty and as a has spent most of his career with the part-time professor of engineering science Engineering Technology Division, where he and mechanics at the University of had served as head of the Pressure Vessel Tennessee. Pugh is a fellow of the Technology Section (1986--1989), manager American Society of Mechanical Engineers of the NRC Heavy-Section Steel and a member of the American Nuclear Technology Program (1982-1987), and Society. He is the U.S. member on the manager of Structural Design Technology International Atomic Energy Agency's in DOE's Liquid Metal Fast Breeder International Working Group on Life Reactor Materials and Structures Management of Nuclear Power Plants and Technology Management Center (1978- coordinates activities with the Fracture 1982). The chief focus of his technical work Assessment Group of the Committee on has been structural materials technology for Safety of Nuclear Installations within the nuclear and non-nuclear applications. His Nuclear Energy Agency of the Organization models of the behavior of inelastic for Economic and Cooperative structural materials have influenced the Development in Europe. analysis of high-temperature structural designs in Europe, Japan, and the United States.

Number Two, 1992 103 Nuclear Plant Life

"The rate of embrittlement in each reactor vessel is monitored with the aid of surveillance programs, and limits are imposed by NRC regulations and regulatory guides that ORNL has helped to establish." Reactor pressure the fuel, the walls tend to vessels in nuclear power lose their ductility. This plants must remain tendency is greater for structurally sound to those vessels that have prevent loss of water used relatively high for cooling the nuclear fuel. concentrations of copper Overheated fuel could (an impurity) and nickel (an result in localized melting of alloying element). Such the vessel wall and thus in radiation-induced the escape of radioactivity embrittlement can occur in into the containment older pressurized-water building. reactors and, to a lesser The thick steel walls of extent, in boiling-water new reactor pressure reactors. vessels possess sufficient Embrittlement and strength and ductility-the thermal shock. Radiation­ ability to accommodate induced damage, or stresses and strains embrittlement, is the aging caused by pressurization, mechanism of dominant heating, and cooling-to concern in reactor pressure prevent vessel failure. Over vessels. Long-term many years, however, as exposure of vessel walls to the vessel interior is neutron radiation causes bombarded by neutrons dislocations of atoms in the from nuclear reactions in steel's crystalline structure,

At the K-25 Site, Bill Pennell inspects the full-size reactor pressure vessel that ORNL obtained from Combustion Engineering 5 years ago for research purposes. ORNL and Pacific Northwest Laboratory are planning to use ultrasound to nondestructively detect tiny flaws introduced Into the steel wall plates of the vessel during manufacturing. Such vessels are no longer being built in the United States. Nuclear Plant Life

increasing its strength but as pressurized thermal shielding between the decreasing its ductility and shock (PTS). nuclear core and the vessel fracture toughness. For older nuclear power walls. During manufacture of plants, radiation-induced A potential method for steel plates for vessel embrittlement is clearly an restoring ductility and walls, crack-like flaws may aging-related issue that "Nuclear plant toughness to an embrittled develop. Welding of the must be addressed if plant vessel is a heat treatment operators can reduce plates and forgings is operating licenses are to be called thermal annealing. the embrittlement another potential source of renewed. ORNL is The technique has never rates of their reactor flaws. As the walls become providing guidance to the been used on a commercial pressure vessels by embrittled, these flaws Nuclear Regulatory U.S. nuclear power plant, could propagate under Commission on this issue but American researchers minimizing neutron severe loading conditions. by estimating the probability have conducted irradiation- bombardment of the One such condition is of failure for reactor vessels annealing-reirradiation vessel." thermal shock, which may as a function of operating experiments to establish occur when the hot walls of time. The rate of the necessary data base a vessel are suddenly embrittlement in each and have studied Soviet subjected to cold water as reactor vessel is monitored experience in annealing a result of loss of pressure with the aid of surveillance nine of their reactor and the operation of safety programs, and limits are pressure vessels. The injection systems to cool imposed by NRC annealing procedure the nuclear fuel. In the regulations and regulatory involves heating the 1980s, ORNL researchers guides that ORNL has embrittled portion of the demonstrated that thermal helped to establish. vessel to a temperature shock, combined with Nuclear plant operators substantially above the repressurization (which can can reduce the operating temperature result from activation of the embrittlement rates of their (288°C) for about one safety injection system), reactor pressure vessels by week. A partial anneal is could (for postulated minimizing neutron achieved at 343°C (the severe conditions) drive a bombardment of the vessel. maximum temperature crack through the vessel Recommended approaches permitted when water is in wall, which could result in a include (1) rearranging the the vessel) , and a "full" loss of essential core nuclear fuel core so that anneal is achieved at cooling water. This used nuclear fuel 454°C (using electric combination of thermal and assemblies are nearest to heaters on a vessel after pressure loading is known vessel walls and (2) adding the water has been

106 Oak Ridge National Laboratory REVIEW removed) to raise the containing sharp-edged that is, pressure and temperature of the vessel cracks to sustain stress. temperature changes that beltline weld metal to Fracture-prevention could drive a crack through 454°C for about six days. margins will progressively an embrittled vessel wall. Soviet vessels differ, decrease as the vessel For normal operation, however, from those in the material absorbs increasing the regulatory requirements United States in that their amounts of radiation- call for plant technical welds run in one rather induced damage specifications to be than two directions. This throughout its operating periodically adjusted to difference permits them to life. preclude operating avoid introducing high, Limits to such damage conditions that could potentially damaging are set to maintain required reduce the fracture- temperature gradients in fracture-prevention margins prevention margins below "ORNL has long the nozzle region of the throughout a nuclear acceptable levels. For been at the forefront vessel during annealing. plant's licensed operating accident loading, they set of developing and These temperature period. Regulatory regulatory limits on the gradients may be requirements are based on acceptable level of validating technology unavoidable during the fractu re-m echan ics radiation-induced damage for assessing annealing of a U.S. reactor technology and use in the vessel material. They fracture-prevention . . . vessel. materials-aging data also define the scope and margms m agmg Fracture-prevention gathered from test reactors acceptance criteria tor reactor pressure margins. ORNL and from mandatory fracture margin researchers calculate surveillance programs for assessments, which must vessels." fracture-prevention margins operating power reactors. be performed to support for reactor pressure The surveillance programs any proposal for continued vessels for the NRC and use steel specimens placed operation of the plant once compare them with the in the reactor pressure the regulatory limits on margins required vessel, which are radiation-induced damage throughout the vessel's withdrawn and inspected have been exceeded. operating life. Fracture- for radiation-induced HSST Program. ORNL prevention margins are damage and the extent of has long been at the calculated using fracture- embrittlement. These forefront of developing and mechanics technology in requirements address both validating technology for conjunction with fracture normal operation of the assessing fracture- toughness, a measure of reactor system and prevention margins in aging the ability of a material potential accident loading- reactor pressure vessels.

Number Two, 1992 107 Nuclear Plant Life

Research that enabled assessments of vessel flawed pressure vessels development of this fracture margins. until they leaked or technology has been In the 1970s ORNL ruptured. They found that performed in the Heavy- researchers focused on the vessels failed only after Section Steel Technology validating the newly being subjected to "In the 1970s ORNL (HSST) Program in ORNL's developed fracture margin pressures about three researchers focused Engineering Technology assessment technology. times the design pressure on validating the Division. The HSST They ran large-scale even when large flaws newly developed Program at ORNL has experiments to verify were present. They fracture margin been supported by the U.S. fracture margin predictions concluded that flaws too Nuclear Regulatory for a broad range of small to be detected would assessment Commission and its pressure vessel loading not pose a safety problem technology. " predecessor, the Atomic and operating conditions. under normal operating Energy Commission , tor Large, thick-walled conditions and that the more than 25 years. pressure vessels fracture-mechanics-based In the late 1960s the containing cracks were fracture margin HSST Program initiated the pressurized to destruction assessment technology development of the fracture in these tests, sometimes provided an adequately toughness data base for with spectacular results. conservative assessment reactor vessel materials, These tests involved a of pressure vessel integrity. which is essential to all broad spectrum of past and In 1978 an incident at fracture margin present ORNL personnel the Rancho Seco nuclear assessments for reactor under the leadership of power plant in California pressure vessels. Large senior scientists and focused attention on PTS. plates of thick reactor engineers such as Richard In 1981 the NRC declared pressure vessel steel were Bass, Bob Bryan, John PTS an unresolved safety purchased and used by Bryson, Dick Cheverton, issue. An ORNL team was HSST researchers to Bill Corwin, Shaffih charged with developing fabricate test specimens, lskander, John Merkle, and testing technology for some of which weighed Randy Nanstad, Claud assessing the ability of over a ton. John Merkle of Pugh, Grover Robinson, aging reactor pressure ORNL played a leading role and Grady Whitman. vessels to withstand PTS in developing the fracture- The researchers proved events without failure. mechanics technology the vessels are safe by Results from their work required to interpret and overpressurizing several were later used as the apply the test results to scaled-down, deliberately basis for regulatory

108 Oak Ridge National Laboratory REVIEW Biographical Sketch requirements that assess a shallow-flaw data base the suitability for service of and developing technology William E. Pennell has aging reactor pressure to apply this data base to vessels. the analysis of reactor been manager of The recent decision by vessel response to PTS ORNL's Heavy-Section the operating utility to retire events. They are modeling Steel Technology the Yankee Rowe nuclear the distribution of stresses Program since shortly plant in Massachusetts was in vessel walls during PTS based partly on results events and trying to after joining the generated using ORNL's determine their impact on Laboratory staff in 1987. technology for analyzing a fracture toughness. ORNL He has an M.Sc. degree vessel's ability to survive researchers are also trying PTS. A preliminary ORNL to better understand the in mechanical report concluded that, factors that start and stop engineering from the based on such factors as crack growth in vessel Cranfield Institute of Technology in England. He uncertainty about the walls. has 29 years of reactor engineering experience, amounts of copper in the The need for these vessel welds, the developments becomes much of it gained at Westinghouse Electric probability of vessel failure acute as operating reactor Corporation's Advanced Reactors Division, where exceeded the NRC's pressure vessels approach he was manager of Reactor Engineering for the acceptance guideline. their currently authorized Current research in the limit for radiation-induced Clinch River Breeder Reactor Project. In 1986 when HSST Program (managed embrittlement and as the U.S. fast breeder reactor development program by William E. Pennell) is managers of older nuclear was cancelled, he joined the Tennessee Valley focused on resolving issues power plants exercise the Authority (TVA) for one year as manager of identified in earlier research option of applying for a programs and refining the license renewal. The HSST Engineering and Technical Services in the nuclear fracture margin Program at ORNL intends power recovery program. At TVA he was assessment process. For to continue the tradition responsible for a staff of 1700 engineers, example, in light of established over the past University of Kansas 25 years of providing the managers, and branch chiefs providing engineering studies of enhanced NRC with research results support to TVA's four active nuclear power sites. fracture toughness for that enable it to address He holds nine U.S. patents in fast breeder reactor shallow flaws in two new challenges as they technology. structural steels, ORNL arise.-William E. Pennell researchers are generating

Number Two, 1992 109 Nuclear Plant Life Component Aging Research

"ORNL researchers have identified improved monitoring techniques that detect early signs of age­ related degradation in power plant components."

In 1985 several check valves failed during operation of the San Onofre nuclear power plant in California (shown here), which was permanently closed in 1992. Since this incident, check valves and other power plant components have received increased attention from the NRC and the nuclear power industry, and ORNL has developed nonintrusive methods for monitoring age-related degradation in valves.

In 1985 several check attention from the Nuclear time, these stressors lead valves failed during Regulatory Commission to degradation and, in operation of the San Onofre (NRC) and the nuclear some cases, failure. nuclear power plant in power industry, and ORNL Safety-related components California, resulting in has helped develop affected by aging include extensive, costly damage to technologies to address valves, valve operators, valves and pipes. these concerns. pipes, pumps, The valves failed as a Check valves and other instrumentation , motors, result of service-induced components of nuclear turbines, diesel generators, wear, or aging. Since then power plants are subject to and heat exchangers. check valves and other age-related stressors, These and other power plant components including wear, corrosion , components have been the have received increased oxidation, and fatigue. Over objects of study by ORNL

11 0 Oak Ridge National Laboratory REVIEW and other national laboratories since the mid- 1980s under the NRC's Nuclear Plant Aging Research (NPAR) . program. The NPAR ' program was chartered to identify and address safety issues related to aging of electrical and mechanical components in commercial nuclear power plants. Howard Haynes (left) and Don casada observe the The program goal calls performance of a check for the NRC, its valve installed in a test loop contractors, and utility in the Engineering Technology Division using licensees to better methods ORNL developed understand the effects of to unintrusively monitor aging on nuclear power valve performance and degradation. A prototypical plants and to identify ways magnetic field concentrator to manage and mitigate device is located on top of these effects. Although the the valve. results of current studies apply to plants during their initial license periods, the program, especially broad spectrum of insights acquired are through studies of electrical equipment and systems, especially important to and mechanical including centrifugal extended plant operation components and safety pumps, motor-operated under license renewal. systems. The local program valves, air-operated valves, ORNL's Engineering was initiated under the check valves, solenoid­ Technology and management of David operated valves, relief Instrumentation and Eissenberg, who retired valves, safety-related Controls divisions and the last year; Don Casada is pump turbine governors, Engineering Division of the current manager of the heat exchangers, auxiliary Martin Marietta Energy program. The NPAR feedwater systems, control Systems, Inc., have played program has begun or rod drive systems, a key role in the NPAR completed studies on a instrumentation and control

Number Two, 1992 111 Nuclear Plant Life

systems, and other internal monitoring appropriate even if codes and parts of reactors. parameters over time (to standards were optimized. The ORNL studies look for trends), the motor In several such cases, identify the causes of age- can be replaced or rebuilt ORNL researchers have related degradation, failure before it fails to work as invented new monitoring mechanisms and modes, designed. techniques. historical operating By participating in For example, after "These studies experience, and existing industry standards and recognizing that it was not provide the inspection and surveillance code groups, such as the possible to adequately information needed techniques for each American Society of diagnose the condition of motor-operated valves to understand aging component or system. Mechanical Engineers and These studies provide the the Institute of Electrical without taking them apart, problems." information needed to and Electronics Engineers, Howard Haynes and David understand aging ORNL researchers can Eissenberg, both of the problems. help ensure that the aging Engineering Technology For some of the of nuclear plant Division, invented a motor- components and systems components and systems current signature analysis studied, the current is properly managed by technique. Motor currents, monitoring techniques were using improved monitoring which can be measured found to be unable to practices. The results of during motor operation, detect or adequately NPAR program research at carry characteristic characterize some sources ORNL have influenced the signatures; when a motor is of age-related degradation. development of several in- operating normally, the To help solve this problem, service testing codes and signature is different from ORNL researchers have standards, ensuring that that of a motor operating identified improved age-related degradation abnormally. By monitoring monitoring techniques that mechanisms will be motor currents and detect early signs of age- recognized and addressed. comparing new signatures related degradation in In some cases, however, with known ones, abnormal power plant components in the NPAR program studies motor operation can be time to take corrective have identified potential identified. Haynes and Bob actions to manage the age-related failure Kryter, both of whom have aging. For example, if mechanisms that could not played important roles in degradation of a valve's be identified by existing ORNL's NPAR program, motor is recognized by monitoring techniques, have successfully

112 Oak Ridge National Laboratory REVIEW demonstrated the ability of monitored for changes in this nonintrusive technique field strength resulting from Biographical Sketch to detect a variety of age­ changes in the internal related degradations in position of the valve's Don Casada is manager of ORNL's Nuclear motor -operated valves and obturator-the part that Plant Aging Research program and leader of the other motorized equipment. blocks or permits flow of A patent on this invention water in power plants. Reactor Research Group in the Engineering has been issued to Martin Patent applications for Technology Division. He manages aging Marietta Energy Systems, these techniques have research performed for the Nuclear Regu latory Inc., and the process has been filed by Energy Commission. A native of Bryson City, North been licensed for use by Systems, which has Performance licensed these techniques Carolina, he holds an M.S. degree in mechanical Technologies, Inc., to MOVATS, Inc., and engineering from North Carolina State Spectrum Technologies Valvision, Inc. University. He came to ORNL in 1988 from USA, and Predictive ORNL has played a vital Maintenance Inspection, role in supporting the Carolina Power & Light Company. Since then he Inc. Additional licenses are NPAR program, whose has worked for the Engineering Technology anticipated. results are being used in Division, studying auxiliary feedwater systems, In much the same way, the license renewal rule­ valve-body erosion, and low-flow degradation of Haynes, Eissenberg, and making process and its Casada identified implementation. ORNL pumps in nuclear power plants and managing deficiencies in check valve researchers have also research. He is co- inventor of nonintrusive monitoring methods and developed novel monitoring methods for check valves and is conceived of improved techniques that will be secretary of the American Society of Mechanical methods. Under the useful to electric utility auspices of ORNL's personnel for routine Engineers Working Group on Check Valves. Advanced Diagnostics monitoring of equipment for Engineering Center, we age-related degradation. developed nonintrusive These contributions will techniques for determining help ensure that the aging the position and condition of nuclear power plant of the internal parts of components is not only well valves. In these understood but also techniques, a magnetic managed so that plants can field is applied externally to continue to operate the valve and electronically sately.-Donald A. Casada

Number Two, 1992 113 Nuclear Plant Life

An interview with Rich Mclean by Carolyn Krause

Extending the operating Rich Mclean of the evaluate the environmental life of most of the 118 Energy Division and socioeconomic impacts nuclear power plants spearheaded the of extending nuclear plant "We identified the operating or expected to be preparation of the operation. The utility issues that utilities operating in the United document, which involved industry will be affected individually must States when their 40-year researchers, editors, and financially because the licenses expire is more cost secretaries from six ORNL NRC will require it to alter address for each of effective than replacing divisions-Energy, Health the power plants to meet the 118 reactors at these facilities with plants and Safety Research, the criteria for license 74 different sites that operate on coal, Environmental Sciences, renewal. My feeling is that across the United biomass, or some other Engineering Technology, the utilities are most States." fuel. This was one Research Reactors, and concerned about conclusion of the Draft Engineering Physics and economics-the costs of Generic Environmental Mathematics divisions- refurbishment and the Impact Statement that a and the Publications financial benefits of team of 25 ORNL Division of Energy extending a nuclear power researchers prepared in Systems. In the following plant's operating life. The 199D-91 for the Nuclear interview with the Review public will be affected by Regulatory Commission editor, he discusses the the environmental and (NRC). document. socioeconomic effects of The 1500-page, two- refurbishing these facilities volume document What are the purposes of as well as the impacts of examines the the generic operating them for another environmental and environmental impact 20 years. socioeconomic impacts of statement (GElS)? refurbishing and relicensing How did the ORNL effort aging nuclear power plants One purpose of the contribute to this final for continued operation for document is to help the rule on renewing licenses another 20 years. It was NRC make informed of nuclear power plants released by the NRC in decisions about renewing that the NRC is expected August 1991 for comments the licenses of commercial to issue later this year? by the electric utilities, nuclear power plants. The government, regulatory and NRC will use the document In addition to drafting the resource agencies, special when writing regulations GElS, we participated in a interest groups, and pertaining to relicensing. public workshop on it members of the public. Another purpose is to November 4 and 5, 1991 ,

114 Oak Ridge National Laboratory REVIEW This West Indian manatee and her calf enjoy the in Washington, D. C. The environment at Homosassa purpose of the workshop Springs State Wildlife Park was to help the public and in South Florida. Manatees industry make more are rare and endangered marine mammals for whom informed comments on the nuclear power plants make document by reviewing all good neighbors. In the the issues and subject winter, many manatees seek out and thrive in the heated matter. The comment water discharged from the period, which began in Crystal River nuclear power August, lasted for 90 days, plant, which is 12 miles from and the workshop was held the state park. Photograph by Doug Perrine. midway through this period. About 200 people from state and federal agencies at 74 different sites across and rivers. Issues were and utilities as well as a the United States. These categorized as aesthetic few members of the public recommendations are to be effects, human health attended. In general, the codified in a license impacts, socioeconomic document was well renewal rule that the NRC impacts, ecological effects, received and, as expected, is to issue. Effectively, the and accidents in which the utilities wanted even NRC will tell each utility radionuclides are released. more issues dismissed, the which issues it should We identified a number state governments address and which ones do of plant-specific issues that expressed concern about not need attention at need to be addressed. For on-site waste issues, and particular plants. Those example, water heated up the public urged a more issues that are dismissed in the process of cooling a vigorous pursuit of by this rule cannot easily nuclear reactor is alternatives to nuclear be challenged during the discharged to a river and power. license renewal process. may adversely affect a In this document, we fishery. The release of made recommendations on What are some examples thermal effluent by another the level of analysis that of issues? plant may restrict the should be performed for recreational use of a 104 issues. We identified An issue is a potential cooling impoundment. At the issues that utilities impact, such as the effects another site, power lines individually must address of nuclear power plants on from a nuclear power plant for each of the 118 reactors fish and other life in lakes could kill an unacceptable

Number Two, 1992 115 Nuclear Plant Life

number of birds. The data employs many people in consequences may be have not been definitive on the community, and unacceptable. However, the issue of electromagnetic provides a tax base that the risk associated with the results in good schools and "Another human field effects around accident may be low. To transmission lines, so we public services, then many illustrate this point, if you health impact not addressed the issue by people in the community assume that you will be hit usually mentioned is summarizing these data. may say, "I like the looks of by a car when crossing the the possibility of the Another more general that plant." The document street, you would consider growth of disease issue was that license addresses these types of that situation unacceptable issues. organisms in the renewal for another 20 because you will probably years could result in greater die. But if you couple the warm water of impacts when the plant is What are the most likelihood of death from an cooling ponds at decommissioned than if it important human health accident with the probability power plants." ceases to operate and is issues of extending the that an accident will decommissioned at the end operating life of 4D-year- happen, then you will say of the original 40-year old nuclear power that crossing the street license. plants? when a car is approaching at a distance is an What are the aesthetic The normal releases acceptable risk. If you look issues? from the currently operating at the risk of a nuclear nuclear power plants will power plant accident Aesthetic issues go not change. We know of no coupled with the probability beyond the color of the studies that show that of a death from it, the risk is paint on the nuclear power these plants pose usually within society's plant. They have to do with unacceptable human health acceptable range. perceptions of the nuclear risks from normal Another human health power plant. Some people operation. Evaluations impact not usually look at the plant in terms of have been done by the mentioned is the possibility its potential to hurt them. NRC on the probability of of the growth of disease They worry about an an accident occurring at organisms in the warm accident that would each plant. This accident water of cooling ponds at endanger their families. The probability is assumed to power plants. These plant may arouse feelings be the same during the organisms, which are found of fear or distress. If the license renewal period. If naturally in shallow ponds plant is a good neighbor you assume that an and lakes that get quite with no hint of an accident, accident will happen, the warm during the summer,

116 Oak Ridge National Laboratory REVIEW pose a small risk to people require about 1000 on-site could be significant at workers, equipment, and who may use cooling workers. At the same time, some sites. plant components during ponds for recreational plant refueling and a year of plant purposes. maintenance activities How would the refurbishment. The other requiring as many as 800 environmental impacts of is the effect of the What are some additional workers will be a relicensed nuclear nuclear power station on socioeconomic issues undertaken to prepare for power plant differ from rare and endangered associated with continued plant operation those of the original species. Could you give preparing a nuclear during the license renewal plant? more details on the power plant for license term. The question that second issue? renewal? must be addressed is The relicensed plants whether the presence of may be safer or at least no Rare and endangered To be relicensed, a these 1800 workers would less safe because of the species are important for nuclear power plant have unacceptable refurbishment of the plant many reasons, one of probably needs to be socioeconomic impacts on and replacement of the wh ich is that it is a legal refurbished. Its worn-out the community. Although parts. New environmental issue. Each time a federal components would be the workers will bring in impacts wou ld come from action is taken , the effect replaced with new ones. In money to spend on the additional waste on rare and endangered our analysis, we assumed consumer goods and will storage on-site and species must be that refurbishment will be pay local taxes, the construction to provide tor addressed. A species at a accomplished in a series of community will have the it. But, for the most part, plant site may have been 3- or 4-month outages burden of providing the environmental impacts declared threatened or starting about 8 years transportation and public of the relicensed, endangered, or a new before expiration of the services, such as education refurbished plant would be species, such as the bald original license. Near the and police and fire pretty much the same as eagle, may move into the time of license renewal, protection, for inmoving those of the original facility. area of a nuclear power each plant would have a workers and their families. plant. 9-month outage so that the Based on past The Draft Generic For the most part, utility can replace or repair experiences, host Environmental Impact nuclear facilities have pressure vessels, pumps, communities will be able to Statement says that two proved to be good valves, controls, turbines, absorb additional project- issues must be neighbors to rare and and other system induced demands tor most considered at every endangered species. In components and refurbish public services. However, reactor site. One is the south Florida, the the facility. demands for housing and impact on the community manatee-a rare and The final 9-month impacts on local of the daily endangered marine refurbishment outage could transportation networks transportation of mammal-is found at the

Number Two, 1992 117 Nuclear Plant Life

Crystal River nuclear power being rel icensed. An groundwater use and quality plant (see photograph on example of such a category (four issues dealing with p. 115). The manatees 1 issue is the need for power plant use of reside at the plant in the generating capacity. groundwater that could wintertime because of the Studies show that nuclear conflict with agricu ltural use heated water discharged power will be needed by during droughts), use of "It is more cost from it. For the same the turn of the century terrestrial resources, human effective to relicense reason, the Turkey Point regardless of increases in health concerns (two issues, nuclear power plant near the use of renewable including disease organisms a nuclear power Miami has become a home energy and conservation. in cooling ponds), socio- plant than to build a for the endangered Most of the surface water, economics (two issues) , and new coal plant." crocodile. hydrology, aquatic ecology, solid waste management A negative impact of and water use issues were (two issues). nuclear power plants on category 1. Category 3 issues include endangered species is the We identified 22 issues rare and endangered destruction of sea turtles, in category 2. These species and transportation which drown after being issues, which must be during plant refurbishment. trapped by the water intake addressed at every reactor Because we cou ldn't reach screens. The NRC works site to determine if the a generic conclusion on with utilities to minimize impacts fall within these issues, we such impacts. acceptable bounds defined recommended that the NRC in the GElS, involve small, and utilities examine them What other issues must moderate, or large impacts on a site-specific basis. be addressed by nuclear that may require mitigation. power plants? An example in the aquatic In what ways is ecology area is entrainment relicensing nuclear power We categorized the and impingement. Two plants more cost effective issues as 1, 2, or 3. Of the other aquatic ecology than building a new coal 104 issues we looked at, issues that must be plant or developing some we defined 80 as too addressed deal with other energy source? Can insignificant to have to be discharge from plants using you give specific cost addressed for each site at either once-through cooling comparisons? the time of relicensing. water or cooling ponds. These issues were not of Other category 2 issues It is more cost effective to sufficient importance to include the cost-benefit relicense a nuclear power keep any of the plants from ratio, conflicting water use, plant than to build a new

118 Oak Ridge National Laboratory REVIEW coal plant because the relicensed nuclear plant of the generating capacity need to pay the large are expected to be very expected to be provided by capital cost for a new similar to those of a new new fossil-fired power facility is avoided or at least coal plant. In terms of plants. delayed. Other existing capital costs, relicensing a energy sources may cost nuclear plant would cost less than relicensing more than a conventional nuclear plants in specific oil-fired or gas-fired plant cases. However, sufficient but would have significantly cost-effective alternatives lower fuel costs. In general, are not currently available of the traditional to displace existing nuclear technologies used to Biographical plants as well as supply the generate electricity, only Sketch additional energy that will coal and nuclear energy be required in the future. would have the long-term Richard McLean is program manager for the Therefore, a cost-effective fuel resources to be viable National Environmental mix of energy sources must sources of baseload Policy Act (NEPA) include relicensed nuclear generation. projects in the Integrated plants. Many energy Analysis and Assessment Section of ORNL's Energy We have developed technologies are being Division. He joined the ORNL research staff in 1974, many specific cost studied at ORNL and shortly before receiving his Ph.D. degree in marine estimates comparing the elsewhere to determine biology from Florida State University. His work has centered on environmental. impact assessment for relicensing of nuclear their potential for energy-related technologies, and he is helping to plants with other commercialization. They transfer this approach to Third World countries. He was alternatives for producing include wind, solar, and chairman ofthe NEPA Working Group of the National electricity. We found that geothermal generation, as Association of Environmental Professionals (NAEP) the capital cost of well as coal gasification, and represents NAEP to the President's Council of Environmental Quality in a national awards program for refurbishing a nuclear plant combined cycle, and fossil­ NEPA excellence. He was recently elected a member of so that it can legally powered fuel cells. The the NAEP's board of directors. He is a founding operate another 20 years costs of some of these new member of the International Design for Extreme may be only about $600/ technologies will tend to Environments Association, which addresses engineering kW of capacity compared decrease as they become and environmental problems in polar regions, the deep with the capital cost of commercialized. However, sea, mines, and space. about $1500/kW for a new except in the very long coal plant. The fuel and term, they are not nonfuel operating costs of a projected to replace much

Number Two, 1992 119 I ~13: Pick A Number What Edwin Abbott Did Not Know about Flatland

By Al an D. Solomon s

magine living in a world of two, d\ others, breaking them up into little rather than three, dimensions. Edwin C.. ~ pieces. Moreover, the Flatland I Abbott (1838-1926}--a prominent U 3 government was highly intolerant of schoolmaster, scholar, and theologian who dissenting opinions, jailing the hero lived in England-anonymously published a of the story for believing that the bpok on this fantasy in 1880.1t's called 2 universe was not really flat. Flatland, A Romance of Many Dimensions. Thanks to insights by the Dutch From our three-dimensional perspective, mathematician, physicist, and the inhabitants of Flatland appear in a astronomer Christian Huygens variety of flat geometric shapes, including (1629-1695), however, we may triangles, circles, and squares. Viewed better understand the intolerance from their perspective, Flatland was 9 and difficult personalities of populated by lines of varying lengths Flatland's people. In a series of and points for very slender people. The works, Huygens showed that book focuses on the impact of a major sound waves in our three­ event in Flatland's history in which a dimensional world move three-dimensional sphere slowly "sharply" through space and passes through the country, first time. That is, if we are standing at driving the Flatlanders away a distance from the source of a from its expanding circular gunshot, for a time we hear intersection with their nothing. Then we hear a rapid world, then slowly report followed again by silence. retreating back to a Not so in Flatland. Here there point, and finally would also be silence until the disappearing. The sound of the shot reached us. But Flatlanders would forever after that time, we view this event as would continue to hear sound time-related. arising from the shot-a kind Abbott seeks to of eternal reverberation. broaden our Because our world is full of conception of time sound, the result would be a by using this constant background noise of physical analogy. varying volume- perhaps According to Abbott, resembling the world of a Flatland was a difficult and dangerous place in parent who has bought a very powerful stereo which to live. Some of its inhabitants were so thin system for his or her teenager- and lasting that, when angry, they could actually run through forever!

120 Oak Ridge National Laboratory REVIEW Abbott's Flatland was published in paperback in its fifth edition by Barnes & Noble Books in 1983.

Further support for the assertion that sound dimensions will find many more interesting things propagation is not "sharp" in two dimensions, as it to tell us. is in three, arises from the analysis of a particular Abbott's Flatland was published in paperback partial differential equation, the so-called "wave in its fifth edition by Barnes & Noble Books in equation," by a number of applied mathematicians 1983. Those interested in learning more about over the past 300 years. More generally, for spaces Huygens' Principle, or sound propagation in having an even number of dimensions (2, 4, 6, ... ) general, can tum to the book Methods of sound propagation would not be sharp, while in Mathematical Physics, Vol. II, by R. Courant and spaces having an odd number of dimensions (1, 3, D. Hilbert (lnterscience Publishers, 1962) or to 5, ... ), it would be. Knowing this, perhaps a future me for more information. ICID visitor to an "Evenland" of an even number of

Number Two, 1992 121 Awards & Appointments

Stan David has been Owen Hoffman has (STIG) for robotics and appointed a corporate fellow received a letter of artificial intelligence. by Martin Marietta Energy commendation from the Bob Lauf, Barbara Systems, Inc. He has also been Colorado Department of Hoftbeins, Igor Alexeff named an honorary member of Health for his ongoing (ORNL consultant), V. K. the American Welding Society contributions to the national Sikka, and D. 0. Hobson and the recipient of its 1993 Health Advisory Panel were inducted into the Comfort A. Adams Lecture overseeing the Rocky Flats International Hall of Fame of Award. Toxicologic Review and Dose the Inventors Clubs of Jim Stiegler, former Reconstruction study. America. director of the Metals and John Hayter, J. N. Allen Croff has been Ceramics Division, has been Leboeuf, and Steve appointed to the newly named ORNL associate Pennycook have been elected formed National Academy of director for Nuclear fellows of the American Sciences/National Research Stan David Technologies, replacing Alex Physical Society. Council Panel on Separations Zucker, who has been named The Carbon Dioxide Technology and special advisor to Martin Information Analysis Transmutation Systems. Marietta Energy Systems, Inc., Center has been named the John McCarthy has been president Clyde Hopkins. Data Archive for the appointed to the Scientific Douglas F. Craig has been Atmospheric Radiation Advisory Committee of the named director of the Metals Measurernent(ARM) United Nations and Ceramics Division. program, DOE's premier Environmental Program 's Vince Mei was one of 27 global change research effort. (UNEP) Marine Mammal international energy experts to Thomas J. Wilbanks was Action Program. participate in a national invited to serve on the Anthony Palumbo development seminar in Geography Task Force of the coordinated a short course at Taiwan to improve the National Council on the 92d general meeting of country's power plants, energy Education Standards and the American Society for conservation technology, Testing. Microbiology. Everett Bloom transportation, . Donald Lee has been Steve Lindberg was communications, housing, appointed chairman of the Air elected a fellow of the social security, and health and Radiation Management American Association for the benefits. Committee of the Advancement of Science and Everett E. Bloom has been Envirorunental Engineering appointed associate editor of elected a fellow of the Division of the American Environmental Reviews, a American Nuclear Society. Society of Civil Engineers. publication of the National Annetta Watson was Tom Ashwood has been Research Council. presented with the invited to serve on a Local J. C. Holloway, Donna "Outstanding Leader and Government Oversight Griffith, Marilyn Brown, Advocate Award" by the East Committee to provide local Ingrid Busch, Patricia Hu, Tennessee Chapter of the input to programs relating to Barbara Hoftbeins, Association for Women in DOE Operations on the Oak Claudette McKamey, Joan Science. Ridge Reservation. Muecke, Elizabeth Dagley, Virginia Dale has been Joseph Herndon has been and Katie Vandergriff were named an associate editor of named DOE's Office of selected as corporate Environmental Reviews, a Space representative to the honorees in the Knoxville John Hayter journal of the National Space Technology YWCA's 1991 YWCA Research Council of Canada. Interdependency Group Tribute to Women.

122 Oak Ridge National Laboratory REVIEW Robert Compton was William Painter has joined Todd A. Anderson received awarded the Jesse W. Beams the Office of Guest and User a Student Presentation Award Medal by the American Interactions to facilitate and from the Society of Physical Society. support the cooperative Environmental Toxicology and Gloria Mei was named a research and development Chemistry for his presentation diplomate of the American agreement (CRADA) process. entitled "Bioremediation of Board of Health Physics. Stephen G. Hildebrand Surface Soils: A Novel Use of Fran Sharples was named has been appointed associate Vegetation." head of the Environmental director of the Environmental Tuan Vo-Dinh has been Analyses Section of ORNL's Sciences Division. invited to serve as an associate Environmental Sciences E. Ward Plummer, an editor of ANALUSIS, an Division. internationally known international journal of ORNL's Graphite Reactor physicist and professor of analytical chemistry. He was was recognized as a Nuclear physics at the University of also selected to chair an Historic Landmark by the Pennsylvania, will be the fust international conference in Fran Sharples American Nuclear Society. In Visiting Distinguished Berlin that addressed toxic 1966, it was recognized as a Scientist at ORNL and will chemical monitoring and the Registered National Historic collaborate with researchers in human health effects of human Landmark. the Solid State Division. exposure to toxic chemicals. Emily Copenhaver, Scott Mark Reeves has accepted Keith F. Eckerman has Taylor, and Janet a two-year appointment as been appointed co-chairman of Westbrook have received manager of the Laboratory- Scientific Committee 57 on the TR-3 awards from DOE's Directed Research and Dosimetry and Metabolism of Training Resources and Data Development Program. Radionuclides for the National Exchange (TRADE), an Eric Hirst has been Council on Radiation organization dedicated to appointed to two committees Protection and Measurements. promoting training techniques. dealing with energy matters: Larry Hawk has been Norman H. Cutshall has the Technical Advisory presented the International Hall been appointed deputy Committee to the Demand- of Fame's Advanced director of ORNL's Office of Side Management Training Technology award by the Norman Cutshall Waste Research and Institute and the Committee Inventors Clubs of America for Development Programs on Energy Statistics of the his and co-worker Joe Turner's (OWRDP) and manager of the American Statistical invention of the Direct Braille OWRDP's Office of Association. Slate, a writing tool for the Technology Development Patrick J. Mulholland blind. Programs. received ORNL's 1991 Mary U ziel has been Richard McLean has been Scientific Achievement presented a Distinguished designated a founding Award for his research on the Service Award by the East member of the International ecology of streams. He has Tennessee Chapter of the Design for Extreme also been appointed by the American Society for Environment Association. National Science Foundation Information Science. Robert Young and Po- to serve on its Special Martin L. Grossbeck has Yung Lu have received a Advisory Panel for Long- been elected a fellow of the letter of commendation from Term Ecosystem Research. American Nuclear Society. the U.S. Air Force for their Barbara T. Walton was Jacqueline M. Grebmeier work on the U. S. Air Force elected secretary of the has been appointed to serve as Steve Hi ldebrand Installation Restoration American Board of a member of the Division of Program Toxicology Guide. Toxicology. Polar Programs Advisory

Number Two, 1992 123 AWARDS & APPOINTMENTS

Committee of the National Arvid E. Pasto has been Organization (NATO) Science Foundation. promoted to leader of the workshop on the "Use of Gerald A. Tuskan has Ceramics Processing Group in Biomarkers in Assessing been named guest editor for a the Metals and Ceramics Health and Impacts of special issue of the Canadian Division. Chemical Pollutants. " Journal of Forest Research, Lynn A. Boatner, Brian C. dedicated to the use of Sales, and Brian Chakou- Seven Energy Systems molecular markers in forest makos won a second-place entries received awards in the tree breeding research. award in the optical 1992 International JohnS. Wassom has been micrographs category at the Publications Competition of appointed to a special task 94th Annual Meeting of the the Society for Technical group of the International American Ceramic Society. Communication (STC). David Commission for Protection Donald R. Stallions has Feldman and his colleagues Against Environmental been appointed manager of the from the University of Patrick Mu lholland Mutagens and Carcinogens, Emergency Management Tennessee received an award which will draft a document Department of the Laboratory of merit in the category of on genetic toxicology risk Protection Division. whole periodicals for Forum assessment guidelines. Tammy Prandini for Applied Research and Loucas G. Christophorou McKenzie has been presented Public Policy; S. Marshall and Lal A. Pinnaduwage with the 1991 Environmental Adams and James E. Beck have been presented the Sciences Division received an award of Excellence in Research award Distinguished Achievement distinction in the category of by the Health and Safety Award for Administrative scholarly/professional articles Research Division for their Support. for "Methods for Fish electron attachment research. Scott McLuckey was Biology-Chapter 12. Robert L. Atchley has named head of the Analytical Bioenergetics"; Virginia Dale been appointed manager of Spectroscopy Section of the received an award of merit in Fire Protection Operations. Analytical Chemistry Division. the category of trade/news A preliminary report from F. Owen HotTman has been articles for "Revegetation of the U. S. Environmental elected to the National Council Mount St. Helens Debris Wilbur Shults Protection Agency gives high on Radiation Protection and Avalanche 10 Years ratings to the Environmental Measurement. Posteruptive"; Elizabeth S. Sciences Division's James C. Nook has been Martin, Larry H. Bohanan, Toxicology Laboratory for appointed head of the Research John Waggoner, Melanie D. the quality of its toxicity data. Services East Department Conger, Mike A. Darnell, Wilbur D. Shults has been within the Plant and Ray M. Evans, and Ed appointed by University of Equipment Division. Aebischer received an award Tennessee Dean Larry Ratner Steve Sims has been named of excellence in the category to the Board of Visitors in the director of ORNL' s Office of of mechanical illustration, line university's College of Arts Radiation Protection. art, black and white, for 3-D and Sciences. Helga Van Miegroet has Map of the Oak Ridge William C. McWhorter received the 1992 National Laboratory Facility; and Richard E. Ziegler have Distinguished Scientific Anna Fraser, Bert been promoted to associate Achievement Award from the Longmire, and Jan Hickman division director and manager East Tennessee Chapter of received an award of of program development, American Women in Science. achievement in the category respectively, in ORNL's Curtis Travis directed a of design graphics, posters, Applied Technology Division. North Atlantic Treaty for K-25 Tiger Team

124 Oak Ridge National Laboratory REVIEW Activities; Robert James Adams, Dami Rich, and Graphics Staff; in scholarly Smith, Darcus Johnson, Zerby and Charles Douglas Robert T. Russell; award of and professional journals, Cynthia Southmayd, Evelyn Hochanadel received an merit, Gay Marie Logsdon, award of distinction, Carver, Cindy Johnson, award of achievement in the Waltina L. Lyons, Tina M. S. Marshall Adams and Margaret Eckerd, Judy category of design graphics, Thomas, Joe Rich, John James E. Breck; award of Neely, Jane Parrott, and presentations, for the Martin Holbrook, Dami Rich, and merit, Barbara T. Walton Phyllis Sumner; award of Marietta Energy Systems, Rosemary Adams; in house and Todd A. Anderson; achievement, Laura M. Yost, Inc., Back School slide organs, award of merit, Judy award of achievement, Anne E. Adamson, Human presentation; and Richard Wyrick, Gloria Caton, Charles D. Scott, John E. Genome Management Booker and Mitchell Ceramic Technology for Mrochek, Martha G. Information System; in Williamson received an Advanced Heat Engines Stewart, Timothy C. Scott, mechanical illustration, line award of achievement in the Program Staff, Tim Ellege, Gordon E. Michaels, Eugene art, black and white, award of category of design graphics, and Marilyn E. Langston; in Newman, and Milicia Petek; distinction, Elizabeth S. exhibits/displays, for promotional materials, award in trade/news articles, award Martin, Larry H. Bohanan, Environmental Sciences of excellence, Wanda G. of distinction, Virginia H. John Waggoner, Melanie D. Division Monolith. Jackson, Berta Swain, Dale; award of excellence, Conger, Mike A. Darnell, Robert A. Eldridge, and Janet H. Cushman, Lynn Ray M. Evans, and Ed Numerous ORNL Lynn Freeny; award of merit, Wright, and Linda K. Shaw; Aebischer; in interpretive publications won awards in Michael R. Aaron, Regina award of merit, Jon illustration, line art, color, the Technical Publications and Stinnett, and Larry W. Jefferson, Deborah Barnes, award of achievement, Mark Art Competition sponsored by Davis; in periodic activity Vickie Conner, Richard B. Robbins and M. B. Lewis; STC's East Tennessee reports, award of excellence, Gammage, Carolyn Krause, interpretative illustration, tone Chapter. In brochures, an AmyL. Harkey, MarshaK. Michael R. Aaron, and art, color, award of award of merit was given to Savage, Lydia S. Corrill, Cindy Robinson; in books, achievement, Mitchell Wanda Jackson and Mark Gay Marie Logsdon, Delores award of excellence, Williamson and Michael Spann; in newsletters, award H. Ogle, Karen N. Gibson, S. Marshall Adams; in Farrell; in design graphics, of excellence, Charles Jon Jefferson, Deborah technical reports, award of brochures, award of merit, Reeves, Jr., Susan E. Barnes, and Vickie Conner; distinction, Robert S. Sandra M. Schwartz; in Hughes, Linda E. Battle, award of merit, Wanda G. Turner, Robert B. Cook, design graphics, covers, color, Allyn Zerby, and Frances Jackson, WalterS. Helga Van Miegroet, Dale award of excellence, Vickie Littleton; award of merit, Bill Konsinski, Jr., Larry W. W. Johnson, Jerry W. Conner, Wanda G. Jackson, Cabage; award of Davis, Vicky Rolfe, Sandi Elwood, Owen P. Bricker, and Beverly Wilkes; award of achievement, Carbon Lyttle, Darrell C. West, Ann Steven E. Lindberg, George achievement, Sandra Dioxide Information Center, Wilson, Deborah Counce- Hornberger, David S. Schwartz and Ken S. Davis; Frederick M. O'Hara, Jr., Brown, Ronald A. Evans, Shriner, Samuel B. in design graphics, posters, Frederick W. Stoss, David Steve Goodpasture, Richard McLaughlin, Margaret K. award of distinction, Anna Fields, Marilyn E. Langston, Grant, Toni G. Jett, Frank Lyday, W. W. Heck, D. W. Fraser, Bert Longmire, and Information Technology Kornegay, Gary W. Snyder, Johnson, J.D. Joslin, C. E. Jan Hickman; award of Group, Cheryl A. Koski, Mark F. Tardiff, Linda Peterson, and P. M. Irving; merit, Sandra R. Schwartz; Ken Davis, Gloria Glandon, Jeffers, Sandi Lyttle, James award of excellence, Larry award of achievement, Anne E. Freels, Shelia E. Mason, Nancy Smith, Dresner, Sandra Vaughn, Sandra R. Schwartz; in Poligone, Margaret L. Thomas Tallant, Vickie ET/FE Publications Office, design graphics, presentations, Givens, and Sandra R. Conner, Carol Hodge, Jamie Brenda Smith, Margaret award of excellence, Robert Schwartz; in organization Payne, and Leon Smith; in Boone Nestor, Judy Neely, James Zerby and Charles manuals, award of distinction, whole periodicals, award of Phyllis Sumner, and Cindy Douglas Hochanadel; award Laura J. Morris, Gay Marie distinction, David L. Johnson; award of merit, of achievement, Mitchell Logsdon, Linda S. Cooper, Feldman; award of merit, D. K. M. Shum, ET/FE Williamson and Uegang Wu; John Holbrook, Rosemary ORNL Editing and Publications Office, Brenda in design graphics, exhibits/

Number Two, 1992 125 A WARDS & APPOINTMENTS

displays, award of distinction, Night, held May 29, 1992, in Military Airlift Command in Richard Booker and MitcheU Knoxville. Two ORNL Operations Desert Shield and Williamson. employees singled out for top Desert Storm in what has been awards who later received the called the largest airlift in The following ORNL Jefferson Cup A ward at history. researchers were honored for Martin Marietta Honors Night receiving patents for their Ceremonies were Inventor of The following ORNL innovative developments: the Year Tuan Vo-Dinh, for employees received a C. V. Thompson (first patent), inventing "the Surface­ Technical Achievement T. N. Tiegs, T. B. Lindemer, Enhanced Raman Optical A ward for excellence of C. D. Scott (fifteenth patent), Data Storage System that technical contributions C. A. Woodward, C. H. offers 100 times greater involving research, Byers, T. L. White (first storage density than current development, engineering, patent), R. A. Hawsey (frrst compact disk technology and publication, or invention Tuan Vo-Dinh patent), T. Vo-Dinh, M. R. has wide-ranging application including a development that Cates, C. T. Liu, V. K. Sikka, in the fields of computing, makes a significant L. Maya, K. H. Valentine health care, government, contribution to a mainstream (tenth patent), D. D. Falter banking, finances, and activity of the company; an (frrst patent), K. G. Falter entertainment"; and Author of invention with realized or (first patent), T. N. Tiegs, the Year Steve Pennycook, potential value to Energy G. F. Dorsey, V. K. Sikka, for detailing "the first Systems, the government, or T. N. Tiegs, T. B. Lindemer, comprehensive analysis of other commercial clients; and T. L. Ferrell (frrst patent), Z-contrast electron a significant contribution as R. J. Warmack (first patent), microscope imaging the author of a publication R. N. Compton, L. Maya conditions which appearing in periodicals, (fifth patent), R. T. Jubin, demonstrates that 'incoherent' proceedings, or books: J.D. Randolph (frrst patent), imaging conditions can be Barbara R. Beatty, for M. R. Cates, M. A. Janney, obtained by using a high­ notable contributions to the 0. 0. Omatete (first patent), angle detector." development of one of the Steve Pennycook C. C. Tsai (first patent), S. M. most efficient and productive Gorbatkin (first patent), The top team award went to transgenic research facilities L. A. Berry (first patent), leader Ronald D. Kraemer in the world; Henry D. W. D. Arnold, Jr., W. D. and team members Ingrid K. Cochran, for developing a Bond, R. J. Lauf (fifth Busch, Susan W. Diegel, fundamental theoretical patent), R. L. Beatty (tenth Kahra G. Gilley, lvor Glen understanding of the structure patent), D. P. Stinton, J. C. Harrison, Michael R. and properties of solutions in McLaughlin (first patent), Hilliard, Alton Huntley, supercritical fluids and R. A. Lowden, C. W. Ronald W. Lee, Cheng Liu, creating useful models; Brian Forsberg, and J. W. T. Stephen Margie, Irene R. Davison and James E. Dabbs. Moisson, Angela K. Sexton, Thompson, for innovative Rajendra S. Solanki, research leading to the Numerous ORNL Cynthia L. Terry, and Ed P. development of the biparticle employees were honored for Tinnel, for outstanding fluidized-bed bioreactor; outstanding accomplishments performance in developing Lawrence Dresner, for in research, management, and the Airlift Deployment sustained contributions as a operational support activities Analysis System (ADANS), leading theorist in applied at the annual Martin Marietta which became the exclusive superconductivity with Energy Systems Awards scheduling system used by the emphasis on the stability of

126 Oak Ridge National Laboratory REVIEW superconductors, protection of McMillan, R. H. Miles, support of the Active/Passive magnets, and development of Robert N. Nodine, Paul Neutron Examination and cable-in-conduit Rathke, Marc L. Simpson, Assay system; Lal A. superconductors; Brendlyn D. David H. Thompson, Dale A. Pinnaduwage and Loucas G. Faison and Susan N. Lewis, Treece, John C. Turner, and Christophorou, for for publication of direction­ Kenneth S. Weaver, for developing a method for setting research in the development of a modular, studying and observing the biotreatment of waste on-line web quality inspection first photoenhanced electron containing low-level radiation system capable of assessing attachment to short-lived and heavy metals by a novel color registration, color excited electronic states of sorption technique; G. A. fidelity, presence and size of molecules; Dan Shapira, J. Geist and Jack J. Dongarra, flaws, image registration, print Gomez del Campo and Hee for development of the width, and web width; Kim, for developing new parallel virtual machine Herbert Mook, Jr., Bryan C. techniques to determine the (PVM), a software package Chakoumakos, John A. lifetime and volume of the Ron Kraemer that enables distributed Harvey, Mark Mostoller, nuclear source of particle computing across and Brian C. Sales, for emission during nuclear heterogeneous networks; observing phonon softening in reactions; Vinod K. Sikka, Virginia L. Godfrey, Eugene a high-temperature for outstanding effort in the Rinchik, and Liane B. superconductor through the development of nickel and Russell, for demonstrating the innovative use of neutron iron aluminides and in the role of the thymus in resonant absorption identification of commercial "educating" T lymphocytes spectroscopy; Pedro J. applications for them; and providing a genetic mouse Otaduy, C. R. Brittain, N. B. Warren G. Sisson, for model for autoimmune Gove, and Luis Rovere, for exceptional service in the diseases; John A. Harvey, for development of an expert design, fabrication, and leading the team that system-based automatic implementation of four critical measured the first non-zero control system that allows a experiments while serving as value for the electric single operator to manage a section quality assurance polarizability of the neutron; three-reactor power block of officer in exemplary fashion; Michael G. Jenkins, Matt the Advanced Liquid Metal Audrey Stevens and Frank Ferber, and Ted Nolan, for Reactor; Steven H. Larimer, for cloning and significant materials Overbury, Charles C. sequencing the gene for a characterization and analysis Havener, Fred W. Meyer, growth-regulating enzyme and contributions to the and David M. Zehner, for demonstrating that its integrity development and explaining the extremely fast is essential for normal cell commercialization of a high­ neutralization that is observed growth; Tuan Vo-Dinh, for performance silicon nitride when highly charged ions inventing the Surface­ ceramic; L. Curt Maxey, for interact with a solid surface; Enhanced Raman Optical developing a novel technique Steven J. Pennycook and Data Storage System, offering for aligning off-axis D. E. Jesson, for establishing wide-ranging applications in paraboloid mirrors that the incoherent nature of areas demanding greatly dramatically reduces optical atomic resolution Z-contrast enhanced storage capabilities; component test costs; Jim A. electron microscope images, Angela B. Walker, for McEvers, Hugh M. Costello, thus ensuring direct, superior initiative, Karen F. Cutshaw, Shaun S. interference-free structure independence, and technical Gleason, James S. Goddard determinations; Larry A. skills in evaluating ORNL Jr., Paul H. Hight, David E. Pierce, for superior technical environmental restoration and

Number Two, 1992 127 AWARDS & APPOINTMENTS

waste management needs; R. Strayer, and Kibbee D. enhancing career development constraints, meeting or Jack L. Yarber, for technical Streetman, for development opportunities for a diverse exceeding schedules, support through outstanding, of the Saturday Academy of staff; Mary Anne Sedlmeier, attaining mission goals, sustained contributions to the Computing and Mathematics; for outstanding administrative training and motivating operation of plasma- Elizabeth L. Dagley, Linda implementation of the new people, and demonstrating confinement experiments. Amburn, Charlene M. DOE order on occurrence support for company values; Horak, and Alan Scott reporting; Randy M. Walker, or specific accomplishments ORNL employees who Icenhour, for superlative for achieving a turnaround in during the award period or received an Operations and leadership in interpreting, the effectiveness of the ORNL over a long period: Robert I. Support Award, which developing, and implementing transportation and packaging Van Hook, for exemplary recognizes significant an effective self-assessment function for radioactive waste achievements in leading improvements to efficiency, program at Oak Ridge and other hazardous materials; ORNL's Environmental major cost avoidance or cost- National Laboratory; Nancy Allison Baldwin, Charles R. Sciences Division in research reduction efforts, innovations Dailey, J. Ken Greer Jr., and Boston, Johnnie B. Cannon, and operations activities; and that enhance programmatic David D. Skipper, for Tina C. Curry, Charles W. Colin D. West, for operations, and extraordinary ignificant achievement in the Hagan, Anthony B. exceptional service as personal effort in support of preparation of Resource Hopwood, and Carolyn H. manager of the Advanced major projects and goals, are Conservation and Recovery Krause, for significant Neutron Source Project. Robert L. Atchley, for Act permit applications and contributions in the innovative leadership closure plans; Norma Jean preparation of the proposal to A Community Service resulting in the most cost- Hensley, for superior site Complex 21 on the Oak A ward, which recognizes effective fire department with performance as section Ridge Reservation; Paula F. outstanding and noteworthy the lowest fire loss ratio in secretary and for promoting Wright, for administrative performance in voluntary Energy Systems; Virginia M. continuity of section business support and dedication to activities of benefit to the Cannon, for unsurpassed voluntarily during her Research Reactors Division community and involving expertise in Energy Systems' supervisor's absence; Robert staff and to the division's considerable personal time, policies relating to hiring, Mason, Thomas H. Monk, missions and goals; S. D. demonstrated dedication and termination, and internal Mark R. Peet, Sharon M. Wright, for excellence in continuous long-term service, payroll status changes; Robinson, Gil W. Sherrill, administrative support for significant contribution to Aurelia Carter, for Warren T. Thompson, and ORNL and the Analytical quality of life in the distinguished service to the John R. Trabalka, for Chemistry Division. community, demonstrated staff of the Metals and exceptional commitment in and recognized leadership Ceramics Division through preparing for application of The following ORNL abilities or considerable enthusiastic cooperation and Federal Facilities Agreement managers received a creativity in the initiation and assistance in division requirements to the active Management Achievement implementation community financial planning, internal Liquid Low-Level Waste Award for contributions projects, was given to G. C. timekeeping, and cost System at ORNL; Donald R. characterized by exemplary Robinson, Jr., for leadership reporting; Edward D. Miller, for innovative performance in leadership, in community service that has Aebischer, Syd Ball, leadership in greatly planning, organization, opened the doors for many Christopher Bottcher, John increasing the quality and staffmg and control functions; children and families to Bownds, Bob Dory, David efficiency of Instrumentation achievements in dealing experience a more Giles, K. Bruce Jacobson, and Controls Division effectively with resource meaningful life. Ill G. Malcolm Stocks, Michael maintenance at ORNL and in limitations and other

128 Oak Ridge National Laboratory REVIEW User Facilities ORNL's SMAC Facility: IIDproving on Mother Nature

ature provides us with materials of Ion implantation doping is the process of varying hardness, durability, firing charged atoms, or ions, of carefully selected conductivity, and a range of other masses and energies at a target, with the goal of traits.N When these materials don't meet our needs, embedding these ions in the near-surface layers of we can take advantage of natural chemical the target material. The higher the energy of the interactions to create substances with more ions, the deeper they penetrate, disrupting the desirable characteristics. However, some normal structure of the target material. specialized technical applications require materials Implantation research at SMAC has resulted in having combinations of characteristics that don't a number of beneficial developments, including a occur naturally and can't be created using standard method of increasing the durability of the wear chemical techniques. surface of a titanium alloy artificial hip joint. Researchers at ORNL's Surface Modification Nitrogen-doping of the wear surfaces of the "/on-beam and Characterization Collaborative Research Center prosthetic joint reduced corrosion and abrasion by processing is (SMAC) specialize in circumventing these a factor of 1000, extending its life and presumably calculated to limitations by firing beams of ions into or onto the reducing the likelihood of subsequent hip surfaces of a range of targets, altering their physical replacement operations. One project this produce or properties and creating materials that Mother technique is currently being used for is a study of enhance Nature never imagined. the structural and electrical properties of Ion-beam processing is calculated to produce or implanted diamond, a material which may have particular enhance particular surface characteristics of applications as a thin-film semiconductor. surface materials, such as hardness, conductivity, adhesion, Ion beam deposition provides a means of characteristics or optical properties. "SMAC is concerned with building up layers of isotopically pure thin ftlms surface modifications, not bulk properties" says on selected surfaces. These films can be used as of Steve Withrow of the Solid State Division. "This research samples to study, for example, the materials." type of research enables us to determine which migration of one isotope into another during combination of ion species and target material to heating. These layered ftlms may ultimately find use to tailor a surface having a particular set of applications in X-ray optics, semiconductors, and characteristics." materials requiring high thermal conductivity. "For instance," says Withrow, "we might want to Ion beam mixing involves bombarding a thin investigate ways to prevent unwanted chemical film of material deposited on a substrate with ions reactions, such as corrosion, or improve the ability that deposit most of their energy near the interface of a material to speed up a chemical reaction, between the two materials, causing them to mix. known as catalysis. Because corrosion and catalysis This results in an intermediate layer of material occur on the surface of materials, they can be possessing new and often desirable properties. influenced by ion-beam processing. Similarly, we This technique may be used, for instance, to could try to reduce the friction between a metal ball attach a thin metallic film to a semiconducting or bearing and a race (the track the bearing rides in) ceramic substrate. Mixing the two materials at because friction depends on the surface their interface improves their adherence to one characteristics of the bearing and the race. These another. Such films could be used for electrical are the kinds of problems we can attack." contacts, wear protection, etc. SMAC researchers rely on a variety of Ion beam annealing may be used in techniques to achieve surface and near-surface conjunction with ion implantation doping to undo modification of materials. Several of these are structural damage in irradiated materials. described here. Annealing is achieved by heating the sample with

Number Two, 1992 129 Darrell Thomas attaches an electrical connector to the target chamber of SMAC's newest accelerator. ion­ beam processing conducted at SMAC enables researchers to tailor surface characteristics of materials, such as hardness, conductivity, adhesion, or optical properties, to meet specific needs.

a beam of energetic ions, thereby allowing Positive ion channeling, the steering of internal stresses built up by the implantation charged particles between rows of atoms in a process to be released. crystalline solid, can be used to gauge the Developing surface modification techniques, perfection of crystal structure, determine the however, is only half of SMAC's mission. The extent of damage to crystal lattice structure other half is the analysis of modified surfaces. caused by ion implantation, locate impurities, and The results of ion-beam processing done at provide a number of other types of information SMAC or of other processes that produce near­ about crystalline samples. surface changes in materials can be studied at Surface analysis techniques employed at SMAC using a range of ion beam and surface SMAC include several varieties of electron analytical techniques. spectroscopy, including low energy electron Ion scattering analysis provides a diffraction and Auger electron spectroscopy. nondestructive, depth-sensitive method of These techniques are primarily used for studying determining the near-surface composition of reordered surfaces and crystal growth and for materials. This technique involves firing hydrogen monitoring surface cleanliness. or helium ions at a target and precisely measuring Computer analysis is also employed to model the angles and energies at which they collide and ion beam interactions with materials, simulate ion scatter. The information gained from these scattering, and predict other particle-solid collisions enables researchers to construct a interactions. picture of the distribution of elements in the Withrow encourages outside users, including surface layer before ion-beam processing and to industrial, academic, government, or foreign measure changes in these distributions as a result researchers interested in pursuing projects at the of processing. SMAC/RC facility to submit research proposals Nuclear reaction analysis is another ion­ describing the scientific problem to be addressed scattering technique used at SMAC. By selecting and estimating the time and support they would an ion species that will undergo a nuclear require. Nonproprietary use of the facility is free resonance or possibly a nuclear reaction as a of charge. result of a near-head-on collision with an atom in "The SMAC facility is highly versatile," says the target, researchers can greatly increase the Withrow. "We can implant ions of just about amount of information gathered from the ion every element on the periodic table at energies scattering. This technique is useful when normal from 10 ke V to 1 MeV or higher. If there's an scattering techniques do not provide enough element you want to implant, we can probably do quantitative information about a particular it." component of the target because, for example, its Mother would be so proud. II concentration is small.

130 Oak Ridge National Laboratory REVIEW I:~ 3= Educational Activities ORNL and ORAU: Partners in Education ~;!:~tiveness of the country's The long-standing educationalA system is regularly science education being called into question, the partnership Oak Ridge area is emerging as a between ORNL proving ground for innovative and Oak Ridge educational strategies and Associated Universities has programs. One of the driving helped establish forces behind this educational the Oak Ridge renaissance is the long-standing area as a proving partnership between ORNL and ground for Oak Ridge Associated innovative Universities (ORAU), which educational operates the Oak Ridge Institute strategies and for Science and Education programs. (ORISE). This partnership can claim a share of the credit for developing in Oak Ridge the largest set of educational programs at a DOE site. handle the recruitment and processing of program The relationship between these two participants. ORNL is a laboratory, so its staff organizations dates back to thel946 debate over handles anything related to research. Our staff what to do with the Clinton Engineering works with Ed Aebischer's staff in ORNL's Laboratories (the forerunner of ORNL), which Office of Science Education on a daily basis. was built in Oak Ridge for the Manhattan Project. When Ed and I go to Washington to make A result of this debate was the formation of the presentations to DOE's Office of University and Oak Ridge Institute of Nuclear Studies (ORINS), Science Education, we represent a seamless a consortium of colleges and universities that was organization-it's not just two groups showing up to become Oak Ridge Associated Universities. at the same place and the same time." This consortium was formed to promote access to "This arrangement is unique in the DOE the unique research facilities at Clinton system," says Aebischer. "We work hard with Engineering Laboratories for students and faculty ORISE to minimize any appearance to partners or of universities in the region. participants that we are two different organi­ Seamless organization. Nearly 50 years later, zations." this ongoing relationship provides a uniquely rich The success achieved by this close cooperation environment for the development of educational has paid off for Oak Ridge as a whole. DOE programs; however, maintaining this environment contractors in Oak Ridge have the largest set of requires a high level of cooperation between the educational programs at any DOE site. "What's two organizations. happening here is happening throughout DOE," "Communication is the key to the says Chester R. Richmond, director of ORNL's relationship," says Wayne Stevenson of ORISE's Office of Science Education and External Science/Engineering Education Division. Relations. "Secretary of Energy Watkins has "Because ORAU is a university consortium, we provided strong support for educational activities

Number Two, 1992 131 EDUCATIONAL ASSISTANCE

and has emphasized education as a primary through high school. "We 're doing a lot more at mission of the department. The reason DOE has the beginning stages of the pipeline that ultimately looked to Oak Ridge is the combination of produces scientists and engineers," says resources at ORNL and ORISE and the links that Aebischer. "We have more programs at the exist between these organizations and other elementary and secondary levels, both for students regional institutions, such as the University of and for teachers." Some of these programs are Tennessee and the Tennessee Valley Authority." described below. The partnership between ORNL and ORAU has • The Science and Mathematics Action for produced thousands of undergraduate, graduate, Revitalized Teaching (SMART) program was "The ORNL postgraduate, and faculty research appointments implemented to combine the resources of and internships at ORNL over the years and has ORNL, ORAU, and schools in Chattanooga, research greatly enhanced the research base of colleges and Roane County, and Harriman to enhance divisions universities throughout both the region and the science and mathematics education. These nation. "ORAU is an avenue into the lab largely have school systems represent very different urban because of its extensive network into the academic and rural environments and diverse student strongly world," says AI Wohlpart, head of ORISE's populations. supported Science/Engineering Education Division. Established in 1989, the SMART program DOE's multilevel University-Laboratory brings teachers together with scientists and the growth Cooperative Science Education Program and two technical specialists from ORNL to develop and newer national initiatives, the Science and new instructional materials and implement Engineering Research Semester and the Teacher development new teaching strategies. To maximize the Research Associates Program, are mainstays of impact of teacher development activities, a of all these DOE's educational effort in Oak Ridge. More communication network has been established, educational recently, increasing emphasis has been placed on linking teacher liaisons at each school with the wide range of undergraduate and graduate programs." each other and with program administrators at internship opportunities and on development of a ORAU and ORNL. Meetings for teachers in new ORNL Postgraduate Research Program each system are held on a regular basis to designed to strengthen the vital contribution that allow them to share information and stay postdoctoral appointments make at ORNL. These informed about SMART activities. varied programs provide research and training Over 200 teachers have participated in opportunities at ORNL in disciplines ranging from SMART workshops and training to assess the environmental science to analytical chemistry to needs of their education programs over the two genetics research. "The ORNL research divisions years of the program's existence. This ongoing have strongly supported the growth and involvement has resulted in system-wide development of all these educational programs," improvements in science and mathematics says Aebischer. "The things we do in this office programs in participating school districts. could not happen without the cooperation of the divisions in matching the research interests of the • Like SMART, the Teachers Research participants with the research needs of the Lab." Associates Program, formerly known as These programs give participants the type of STRIVE, emphasizes helping teachers develop research experience that's not available on innovative methods of communicating the campus, providing them access to state-of-the-art importance of scientific research to their equipment and enabling them to collaborate with students. This program gives junior and senior world-class researchers. high teachers the opportunity to spend part of Joint projects. The latest trend in joint ORNL­ their summers as members of research teams at ORAU educational projects has been to broaden ORNL, ORISE, or one of six other DOE their scope to include programs for precollege research facilities. A portion of each week is students and their teachers-from kindergarten spent exploring ways to incorporate their

132 Oak Ridge National Laboratory REVIEW research experiences into their teaching Supercomputing" (AiS), is being offered by activities. ORNL; Ames Laboratory, Ames, Iowa; and • The Minority Challenge Program promotes Sandia National Laboratories, Albuquerque, interest in science and engineering among New Mexico. junior high and high school students in five Richard Hicks, AiS coordinator for ORNL, counties surrounding Oak Ridge. The program said that the response to the program in includes career awareness workshops, visits to Tennessee has been tremendous. "We had more college and university campuses, summer than 40 schools across the state apply," Hicks internships, and a summer science camp where said. "I was pleased with the enthusiasm that all students participate in classes and laboratory of the teachers expressed about the need for this experiments. type of program in Tennessee." A committee composed of Tennessee state officials, educators, • Last year's East Tennessee Regional Science and ORNL personnel selected seven high Bowl, cosponsored by ORNL, ORAU, and schools from the applicant pool. Pellissippi State Technical Community AiS is based on a teaching curriculum first College, drew 26 high school teams from developed and tested in Alabama schools. In this Tennessee and Georgia to vie for the privilege successful program, high school students of competing in the National Science Bowl in produced computer simulations to study Washington, D.C. heredity, the aerodynamics of a wind tunnel, the • Area high school students joined hundreds of progression of the AIDS virus in a human body, college students and faculty members at the and the thought patterns of a schizophrenic third annual Women in Science and person. Technology Conference. The conference Under the AiS program, participating schools highlighted expanding scientific career received free loans from DOE of four Macintosh opportunities for women in government, computers, which are networked to a medicine, academia, and private industry supercomputer manufactured by nCUBE through lectures and discussions. Corporation. The nCUBE supercomputer, which These programs and a host of others are a sign is a multiple-processor, massively parallel of the continually expanding commitment on the supercomputer, is being loaned by nCUBE part of DOE, ORNL, and ORAU to meet the Corporation of Foster City, California, at no cost challenge of providing today's students with the to ORNL to implement the AiS program. Bobbi kind of high-quality science education that will Hazard, vice president of sales for nCUBE allow them to compete and succeed in the world Corporation, stressed nCUBE's commitment to of tomorrow.-Jim Pearce education. "Today's students are the researchers and engineers of tomorrow," Hazard said. "Exposing "Adventures in Supercomputing" students to leading-edge technology, which Program at ORNL normally is available only to the elite in scientific research and commercial industries, DOE has funded a program to introduce will significantly improve the students' supercomputing concepts into the high school education, and in the long term, the computer classroom in Tennessee, Iowa, and New Mexico. industry as a whole."-Anne E. Armstrong r:!l The new program, "Adventures in

Number Two, 1992 133 R&D Updates Laser Technique Detects Pollutants in Fish

"The scales of a fish have annual growth regions like tree rings," says Arakawa. "Thus, we can determine in which seasons and in which years it was exposed to certain pollutants, such as pesticides, mercury and other heavy metals, and PCBs. Samuel McKenzie, "Because we know the local a physicist in the striped bass spend the summer in the Health and Safety Clinch River and the winter in Watts Research Division, Bar Reservoir and because we can inspects a fish pinpoint when the fish were exposed scale before to certain pollutants, we should be inserting it in the able to determine where contaminants sample chamber are most concentrated. The fish scales for pollutant we examined indicated that the fish analysis using two lasers. were exposed to less pollution in the Clinch River than in the Watts Bar Reservoir." The technique includes the use of laser ablation to vaporize different regions of a fish scale, which is composed of calcium and magnesium. An ultraviolet light from an excimer laser knocks off a few atoms from the fish scale and removes electrons from these atoms, making them positively charged ions. These ions form a beam that is pulled by an electric field into a time-of­ flight mass spectrometer. sing a laser and a mass spectrometer, Because of the different masses of the ions, they ORNL researchers can detect trace slow down at different rates and are detected at pollutants in fish and determine when different times, permitting identification of the Uand where the fish were most exposed to these different elements in the fish scale. One of the pollutants. The technique permits scientists to "peaks" on the mass spectrometer readouts for map sources of contamination inexpensively and recent ORNL experiments indicated the strong determine the contamination history of a fish presence of chlorine. The source of the chlorine, without harming it. Arakawa says, is probably PCBs. ORNL researchers led by Ed Arakawa, leader Chuck Coutant, an expert on the effects of water of the Physics of Solids and Macromolecules temperature on fish, proposed the idea of applying Group in the Health and Safety Research the technique to detecting pollutants in the scales of Division, have demonstrated the technique using local fish. Coutant and Marshall Adams, both of the fish scales from striped bass. They believe they Environmental Sciences Division, remove a few have detected polychlorinated biphenyls (PCBs) scales from striped bass, which are then returned in the scales of fish three years old or younger. alive to the river, and supply them to Arakawa's

134 Oak Ridge National Laboratory REVIEW group for study. The original analysis was done by produce fuels and chemicals from fossil materials Ida Lee, a postdoctoral scientist; physicist Samuel and renewable feedstocks, including recycled McKenzie; and Arakawa. waste material such as paper. Researchers also If additional funding can be obtained, will develop bioprocessing systems to remove and McKenzie and his colleagues will use two degrade pollutants. ultraviolet lasers to extend the technique to Funding for the center comes from the detecting pesticides and heavy metals and Department of Energy. Other government measuring pollutant concentrations in fish scales. agencies benefiting from ORNL's contributions "Transferring To determine the accuracy of their technique, they will include the Department of Defense and the will compare their measurements of pollutants in Environmental Protection Agency, which need bioprocessing the outer edge of scales of dead fish from the advanced techniques for environmental control technologies Savannah River Site with the results of analyses technology and waste recycling; the National to industry of the total content of each fish.-Carolyn Krause Institutes of Health, which can use advanced processing techniques to produce therapeutic will be the agents; and the Department of Agriculture, which ultimate goal New Bioprocessing seeks processes for the small-scale conversion of of most of R&D Center at ORNL surplus and waste agricultural products. ORNL has established an interlaboratory our research A Bioprocessing Research and Development initiative for bioprocessing research and and Center has been established at ORNL in development with Argonne National Laboratory recognition of the increasing importance of in Argonne, Illinois; the Idaho National development biotechnology to the nation's long-term security Engineering Laboratory in Idaho Falls, Idaho; and work." and economic prosperity. Bioprocessing uses the National Renewable Energy Laboratory in living organisms to produce new products. Results Golden, Colorado. Laboratory scientists will also from ORNL's expanded bioprocessing research collaborate with several university laboratories, and development effort will be transferred to the including the Center for Environmental industrial sector to help make the United States Biotechnology at the University of Tennessee in more competitive in the marketplace. Knoxville. Under the new initiative, scientists from ORNL's achievements in biotechnology over ORNL's Chemical Technology Division, the years include (1) creating advanced techniques supported by the Biology and Environmental for producing liquid and gaseous biofuels to Sciences divisions, will develop bioprocesses for provide alternatives for meeting future energy energy-related programs and environmental demands, (2) developing bioreactor systems for control and will produce a variety of commodity producing ethanol and other chemicals, (3) and specialty chemicals. removing nitrates and phenols from industrial "The hallmark of our efforts, supported by wastewaters using microorganisms, and (4) using some 25 years of past experience in bioprocessing biological agents to remove hazardous material research, will be to expand interactions with from polluted soil and groundwater. academia, other national laboratories, and Funding for programs within the Bioprocessing industry," says Chuck Scott, senior corporate Research and Development Center is being fellow and newly appointed director of the center. provided by several DOE offices, including the "Transferring bioprocessing technologies to Office of Energy Research, the Office of industry will be the ultimate goal of most of our Technical Coordination, the Office of Fossil research and development work." Energy, and the Office of Industrial ORNL scientists will concentrate on Technologies.-Brian Daly bioprocessing systems that can economically

Number Two, 1992 135 R&D UPDATES

"ORNL's wall probe can also be used for inspection of building foundations, concrete walls, bridge pillars, and road surfaces." The portable microwave wall probe (shown here mounted on a mock wall section) provides a nondestructive method of locating irregularities in walls, such as cracks or variations in internal structures.

to NDE, but their drawbacks are low resolution Off-the-Wall Idea and high cost. for Structural When a group at the Oak Ridge Y-12 Plant began looking for an NDE technique to examine Evaluation the condition of the hollow clay tile block walls of some of Y -1 2' s older buildings, Don Bible, Carl Nondestructive evaluation (NDE) of structures, Sohns, Richard Crutcher, and Randal Maddox, all such as walls, bridges, and overpasses, is used to of ORNL 's Instrumentation and Controls determine how much they deteriorate as they age. Division, came up with the idea of using a low­ Traditionally, techniques such as ultrasonics or power microwave probe to do the job. radiography have been employed for NDE; "DOE officials were concerned about the however, the limitations of these techniques make potential effect of an earthquake on these walls," them unsuitable for many situations. Bible says. "They knew how the walls were Ultrasonic systems can measure the depth or supposed to have been built, and they knew they thickness of some materials with high precision, weren't always built that way. They needed a but they require a smooth surface through which nondestructive way of getting an internal picture to pass sound waves. Radiography using of the walls to locate irregularities. As a result, we X rays or isotope sources is slow, requires the began to develop a portable microwave diagnostic structure to be unoccupied, and requires access to probe. both sides of the wall. Infrared thermography and "At first, we tested mockup walls with ground-penetrating radar have also been applied sophisticated lab equipment and various

136 Oak Ridge National Laboratory REVIEW microwave frequencies. Then we came up with detectors. Bible expects that this inexpensive, the idea of transmitting a simple reference signal easy-to-use probe would benefit agencies charged into the wall at an angle and comparing the wave with inspecting and maintaining the nation's characteristics of the signal going in with those of infrastructure, allowing limited funds to be used the reflected signal coming out." on structures most in need of repair. The microwave signal transmitted into the -Jim Pearce structure is partially reflected by different layers of materials or irregularities, giving a composite reflection that contains information about each Studying Snails and internal layer. This composite signal is Stream Health considered the "signature" of the structure under test. "Standard" signatures are obtained from A type of snail that is abundant in most streams structures of known composition that are in good in east Tennessee is noticeably absent in condition. contaminated Oak Ridge streams, indicating a When the signature of the test structure significant level of pollution. Such a snail could matches the standard signature, the structure is serve as a sensitive indicator of and contributor to considered normal. A test signature that differs improved water quality in Oak Ridge streams as significantly from the standard may indicate remediation programs take effect. irregularities in composition or it may be a sign These are two conclusions of a recent study by "Elimia of structural deterioration. By varying system Walter Hill, a research associate in the University parameters, such as the frequency of the of Tennessee's Graduate Program in Ecology, and snails have microwaves or the separation between Arthur Stewart of ORNL's Environmental probably transmitting and receiving horns, the system can Sciences Division. These stream ecologists have been be customized for a wide variety of structures. focused on snails of the family Pleuroceridae and A more rigorous challenge for the microwave of the genus Elimia, which are present in large eliminated probe was a test wall built at the K-25 Site. "The numbers in freshwater habitats. Such snails are from Oak K-25 wall incorporated a lot of irregularities," particularly useful as indicators of the presence of Bible says. "They filled some blocks with mortar contamination. Ridge and stuffed paper or rubber gloves into others­ Elimia snail studies have been funded by Oak streams anything they could think of that workers might Ridge biological monitoring and abatement because of have done while building the walls at Y-12. programs set up to assess the impacts of pollutants That's when we decided to use a computer to on stream life. These programs are required by the pollutants." compare test signatures with an entire set of National Pollution Discharge Elimination System standard signatures representing a range of permits issued to Department of Energy facilities, possible wall characteristics." including those on the Oak Ridge Reservation. Once tuned for a particular structure, the In their paper "Grazers, Periphyton and simple readout eliminates problems of Toxicant Movement in Streams," Hill and Stewart interpretation and allows large areas of a report that Elimia have probably been eliminated structure to be rapidly examined. Eventually, from Oak Ridge streams because of pollutants Bible hopes to incorporate the entire system into such as polychlorinated biphenyls (PCBs), heavy a simple, hand-held unit that can be used by metals (mercury, cadmium, and chromium), individuals with a minimum of training and will chlorinated drinking water, and once-through display the results of its analysis on a liquid cooling water discharges. The absence of Elimia, crystal display screen. the scientists add, not only makes it difficult to The probe can also be used for inspection of study the indirect biological effects of building foundations, concrete walls, bridge contamination but may also lead to an increased pillars, and road surfaces and for the location of accumulation of contaminants in fish and other hidden polyvinylchloride pipes that elude metal animals higher in the food web.

Number Two, 1992 137 R&D UPDATES

In addition to helping scientists monitor stream health, the snail also may help preserve it. Elimia feed mainly on masses of algae, "In addition bacteria, and other organic material to helping that form a slimy film called scientists periphyton. High populations of the snail graze periphyton down to a monitor thin layer, preventing nuisance stream blooms. Other invertebrate species do not control algal biomass as well health, the as this snail. snail also "By feeding on periphyton," Hill may help says, "the snails increase the movement of toxic substances preserve it." downstream. If ·periphyton is allowed to flourish, the sticky film will take up many toxicants, slowing their net movement Elimia are individually tagged for mark-release-recapture studies. downstream. As a result, biologically available concentrations of toxicants in The ecologists have used Elimia to study growth streams with low populations of Elimia snails can rates in three streams near ORNL and plan to remain high, and the toxicants enter the food web transfer individually tagged snails to polluted more easily." ORNL streams to determine whether A recent study showed that the concentrations decontamination efforts have been successful. of mercury, cadmium, and chromium in East Fork "Elimia is the dominant invertebrate in many Poplar Creek are many times higher in the creek's uncontaminated streams in eastern Tennessee," periphyton than in the water itself. The creek says Hill. "Several thousand snails can be found receives discharges from the Y-12 Plant, a nuclear per square meter. This snail owes its dominance weapons production facility in Oak Ridge. partly to its thick shell, which protects it from "The absence of this snail in Oak Ridge scouring floods and predators such as crayfish and streams," Hill says, "probably increases the fish." movement of toxicants into stream food webs. This type of snail, Stewart says, is well suited for This effect results from the expansion of the studying the biological effects of toxic materials in periphyton biomass, which accumulates streams. It can live in a stream as long as 10 years, contaminants in greater quantities the more it permitting extended studies of aquatic conditions. grows. Soft-bodied grazers that feed on periphyton It is sensitive to various toxic substances, and its become more abundant and further concentrate the response can be measured. For example, it pollutants, which move into the food web because responds to toxicants by eating less (reduced these species make a good food for fish." feeding rate) and by dispersing in a certain pattern. Hill and Stewart see the Elimia snail as an "Elimia tend to move upstream when water example of a sensitive key species whose removal quality is good," Stewart says, "and downstream will amplify pollution effects. "As when water quality is degraded. Because of the ecotoxicologists," Hill says, "our challenge is to large size of the snail, we can determine its rate and understand and predict the ecological direction of movement remotely with a video time­ consequences of both direct and indirect effects of lapse recording." pollution. "-Carolyn Krause

138 Oak Ridge National Laboratory REVIEW Fish and Wildlife Service, the U.S. Geological ORNL Contributes to Survey, and the Environmental Protection Agency Wetland Management agreed on a standardized classification scheme for defining categories of land cover. To help the nation monitor gains and losses in its For each area being monitored, current and wetlands, ORNL is playing an important role in earlier satellite scenes must be selected, and designing a program to measure changes in coastal careful attention must be given to cloud cover, land cover-marshes, swamps, forests, farms, and tidal stage, and vegetative season. Training urban areas-and to provide reliable data on these samples containing areas of known land cover are changes. Two researchers in the Computing and selected with the help of wetlands ecologists and Telecommunications Division at ORNL are regional specialists and are then matched with working with the National Marine Fisheries patterns of light reflected from the known area, as Service to develop the CoastWatch Change identified through remote sensing by satellites. "To help the Analysis Program (C-CAP). Since the early 1980s Satellite images consist of 30-m2 rectangles Jerome Dobson, a senior research staff member, called pixels; data for each pixel indicate the nation and Edward Bright, a geographic information amounts and wavelengths of light reflected from monitor its analyst, have been developing the program, which the surface. The type of land cover in each pixel wetlands, is supported by the National Oceanic and can be determined through statistical analysis Atmospheric Administration (NOAA). comparing unknown pixels with the training ORNL is A recent proposal to change federal policy to samples, Dobson said. "This way we can detect, helping to open once-protected wetlands to development for example, whether we're looking at an urban angered some environmentalists. The controversy area or an agricultural area." He explained that design a hinged on questions on the definition of wetlands, multiple samples of each area are selected to program to the role they play in the environment, and the represent each land-cover classification. Then the measure wetland area lo s~ to development or natural classified land cover is graphically overlaid on a changes. map. changes in Wetlands are those areas of the landscape where After initial classifications have been made, the coastal land land and water meet. They help to control flooding, researchers begin tests for reasonableness and purify water, and provide an important habitat for consistency. These are accomplished by comparing cover and to fish and wildlife. selected areas with other wetlands data sources and provide "The pressure to protect wetlands has been by investigating the appearance of unlikely pixels, reliable data growing in concert with the environmental such as urban pixels showing up in areas where movement," Dobson said. "As a result, several cities are not known to exist, he explained. "Once on these agencies are supporting a national effort to map we're satisfied with the results for each current changes." land cover and detect wetland gains and losses." scene, we add adjacent scenes to create a single Mapping will be done with the aid of geographic regional data base," Dobson said. "Then we repeat information systems, satellite and aerial data, and the entire process fer the earlier time period based various ground-based data bases. on the same ground control points." He said the Dobson said the greatest chaJJenge lies in the process of detecting changes between the two sheer size of the effort. "Detecting changes in small scenes consists of a pixel-by-pixel comparison and areas can be accomplished by maldng image-to­ the creation of a matrix for recording the changes. image comparisons, but detecting changes for areas Dobson said no literature previously existed on that cover hundreds or thousands of square how to assess error levels for changes from one kilometers is more difficult," he said. To obtain time period to another. "We brought in the top accurate comparisons, C-CAP researchers first had error-estimation specialists, who came up with a to develop a consistent method of categorizing land new and clever solution that involved focusing cover (e.g., agree where marshes end and first on the area and then on the classification," he grasslands begin). In September, NOAA, the U.S. said.

Number Two, 1992 139 R&D UPDATES

Although national in scope, C-CAP will be Until recently, wireless communication in large­ administered as a series of regional efforts with volume hot cells had been considered impossible help from state governments and universities. because the metal walls of the cell cause Candidates include Chesapeake Bay, Galveston electromagnetic echoes, or reflections, that confuse Bay, Tampa Bay, coastal South Carolina, North robots. The new method employs directional radio Carolina, and Rhode Island. "Selected regions waves of very high frequency to reduce the will be monitored every five years, except for reflections to an acceptable level. It also eliminates areas that have experienced environmental damaged and tangled robot wires. disasters or rapid population growth," he said. ORNL engineers have tested the new concept by "Those will be monitored more frequently. " constructing a Transportable Reflecting Dobson believes the methods and technology Environment Communication System (TRECS). developed for C-CAP are the same as those The radio computer system sends signals to the needed for global environmental monitoring and robot's computer, enabling it to perform duties modeling. "The same protocols developed for C­ within a cell about the size of a football field. CAP TRECS' electronics are designed to withstand and the care taken in its development are needed temperatures up to 60°C (1 40°F) and doses of for monitoring such problems as deforestation and gamma radiation up to one million rads (200 rads is desertification. The consistent land-cover considered lethal to humans). Although relatively classifications are especially important to global maintenance-free, the system is designed monitoring, where we encounter very subtle modularly to facilitate any needed remote gradients from temperate to tropical vegetative maintenance. species," Dobson said. "Also, if sea levels begin Use of this system will eliminate the large cable to rise, the most sensitive indication of these bundles that would otherwise be required between changes will be differences in coastal vegetation." the walls of the cells and the operating robots. Accuracy assessments for C-CAP will soon be "TRECS has been fu!ly developed and tested and is completed, and Dobson said initial results have ready for commercialization," says Steve Schrock been encouraging. "If the results are as good as of ORNL's Robotics and Process Systems we expect them to be, C-CAP will provide more Division. "We expect the system could be adopted than just an effective measurement of changes in for use in hot cells toward the end of this decade." coastal wetlands. It will also be an effective tool As part of a DOE cooperative agreement with for analyzing public policy and practices to ensure the French Commissariat a I 'Energie Atomique valuable U.S. wetlands are protected, and it could (CEA), French researchers recently tested the provide environmental analysts with the means to TRECS on robotic equipment installed in metal­ monitor changes in global environmental lined facilities in France. Shrock said the testing conditions."-Karen Bowdle was "very successful."-Brian Daly Wireless Robots ORNL Produces in Hot Cells a New Batch Robots can now move freely in a highly of Research Isotopes radioactive environment too hazardous for humans, thanks to a new method of wireless A campaign to produce isotopes of transuranic communication developed at ORNL. With this elements for use in research at DOE laboratories invention, engineers in ORNL's Instrumentation and at other scientific facilities has been and Controls Division have made it possible for successfully completed at ORNL's Radiochemical untethered robots to operate freely in hot cells Engineering Development Center (REDC). This used for reprocessing nuclear fuel. was the first group of such target isotopes

140 Oak Ridge National Laboratory REVIEW processed since operations resumed in early 1990 at the Laboratory's High Flux Isotope Reactor (HFIR) following a three-year shutdown for procedural reviews. The REDC is the production, By manipulating storage, and distribution center telerobotic arms in for DOE's heavy-element a hot cell, Ben research program. "It is the Smith remotely world's premier facility for such works on work and the only outlet for separating many of the heavy elements," transuranium said Bob Wham, REDC manager. elements, such as "To continue advancing our berkelium, californium, knowledge of heavy elements, einsteinium, and there must be basic research. And fermium. this center is the ground floor for that basic research." Transuranic elements, which are called heavy elements because of their high isotope can be used for the simultaneous detection atomic weight, do not occur naturally on the earth. in food of toxic heavy metals, such as arsenic or They are artificially produced by bombarding the mercury. nuclei of elements such as americium and curium Californium is also part of a technique now with neutrons. At ORNL, such radioactive isotopes being used at several major airports in the United are produced in the HFIR. States and Europe to detect hidden explosives in air "We have an abundance of requests from the passengers' luggage. Because it fissions research community for these ORNL-produced spontaneously and emits neutrons, californium is elements," Wham said, adding that the temporary used by universities as a "substitute reactor." shutdown of the HFIR had created somewhat of a Wham said that students using the element learn backlog. "Laboratories and other facilities that how to develop reactor instrumentation and to depend on us to supply the material for their analyze the spectrum associated with fission research were anxious for us to be back in without requiring an actual nuclear reactor. business." The REDC is operated for production 24 hours a However, the interim period of the HFIR day by members of ORNL's Chemical Technology shutdown was not a time of idleness for the REDC, Division and support personnel from other according to Wham. "The HFIR shutdown actually divisions.-Wayne Scarbrough allowed us time to upgrade our system and to hone our operation so that we can continue to accomplish the goals of our campaigns safely and Global C02 Emissions in compliance with regulations." Rise at a Lower Rate Uses for the heavy elements produced during the

) latest ORNL campaign range from studies in Global carbon dioxide (C02 emissions from nuclear physics to cancer research. One transuranic industrial sources continue to rise but at a lower element that has multiple applications is growth rate than in recent years. According to a californium. The Food and Drug Administration special issue of CDIAC Communications proposes using califomium-252 for determining the commemorating the lOth anniversary of ORNL's presence and concentration of sodium in food. The Carbon Dioxide Information and Analysis Center

Number Two, 1992 141 R&D UPDATES

(CDIAC), the 1989 estimate for global emissions light degrades optical performance. Researchers of carbon represents a 1.2% growth over the 1988 minimize this light by using optically black value, "a notable drop from growth rates of the (nonreflective) surfaces, such as liners, baffles, past several years." and beam stops. Unfortunately, the most common methods of creating optically black surfaces­ The 1989 value for global C02 emissions from fossil-fuel consumption, cement manufacturing, etching, coating, and anodization (an and gas flaring is 5.97 gigatons (thousand million electrochemical process that produces a layer of metric tons), compared with 5.90 gigatons for oxide on metal surfaces)-all have shortcomings 1988. Emissions from the use of natural gas and that restrict their usefulness. other gas fuels and from cement production Etching decreases reflectivity, but only if the contributed less than 4% to the total carbon wavelength of the light is smaller than the etched emissions for 1989, which was the sixth surface features. Anodized and coated materials

consecutive year that global C02 emissions have are also effective optical absorbers, but their light­ "Issues in increased. absorbing surfaces are easily damaged. Anodized In commenting on CDIAC's lOth anniversary, beryllium, among the most widely used material data Mike Farrell, former director of the center, writes for optical absorbers, is too reflective to be used at management that, in 1982, he believed that "climate change certain wavelengths, and because beryllium can be research was going to be highly theoretical and an toxic, precautions increase processing costs. are now area that would never draw much attention from To get around these shortcomings, Bob Lauf of recognized the public." Ten years later, Farrell notes, "global ORNL's Metals and Ceramics (M&C) Division as equally change is the environmental problem of the 1990s and Roland Seals of the Oak Ridge Y -12 Plant's and beyond." In fact, Farrell, Paul Kanciruk, and Development Division became interested in important in David Reichle, all of ORNL, presented papers at creating an absorber that would perform over a understanding the world's largest conference, the United Nations broad band of wavelengths and be durable enough global Conference on Environment and Development to withstand normal handling. (the so-called Earth Summit) in June 1992 in Rio They decided to study the feasibility of creating change as de Janeiro, Brazil. such a broadband absorber using a composite the research CDIAC is a data management and distribution material known as carbon-bonded carbon fiber center. It develops, collates, and provides (CBCF). CBCF, used commercially as a high­ that extensive quality-assurance audits on data bases temperature furnace insulator, has also been produces the that are critical to understanding global change. manufactured by other M&C personnel for use as data." Future initiatives include developing interactive thermal insulation for radioisotope thermoelectric data-analysis systems using a network of generators aboard the National Aeronautics and computers dispersed throughout the world. Space Administration's space probe, Ulysses. The According to Farrell, recent statements by material is made by mixing a water-based slurry Allan Bromley, President Bush's science advisor, of chopped carbon fibers and a resin binder. The and the establishment of the Interagency Working slurry is vacuum-molded, dried, and then heated Group on Data Management for Global Change slowly to melt the resin and bind the fibers under the Committee on Earth and Environmental together. Finally, the resin is converted to carbon Sciences umbrella suggest that issues in data at high temperatures, and the component is management are now "recognized as equally machined to its final shape. important in understanding global change as the Lauf and Seals persuaded Clyde Hamby of the research that produces the data."-Carolyn M&C Division to formulate several batches of Krause CBFC with less fiber and more binder, hoping to create a material that was more rugged than standard CBFC. After some tinkering with the Broadband Absorber recipe, Lauf and Seals found what they were Leaves Optical Systems looking for. The resulting material is uniquely well suited in the Dark for use as an optical absorber for a variety of reasons. First, because CBCF is a bulk material In precision optical systems, such as telescopes, rather than a surface enhancement or coating, it is camera lenses, and test equipment, stray reflected optically black throughout, making it immune to

142 Oak Ridge National Laboratory REVIEW surface damage. Another M&C co-worker, AI Akerman, demonstrated that CBFC can be sanded and machined without losing its light-absorbing properties. It Bob Lauf is unaffected by small examines a variations in processing, variety of CBCF components. unlike anodized or vapor­ Because CBCF is deposited coatings, which optically black are highly sensitive to throughout, it is process variables. In immune to addition, it absorbs light surface damage over a much wider spectrum and can be than many standard optical sanded or absorbers-up to at least 50 machined into microns, compared with 10 almost any shape while still retaining microns for etched its absorbing beryllium. Also, it is properties. lightweight, easily fabricated into almost any shape, and, because of its low atomic weight, it is highly resistant to radiation and thermal damage. testing of optical equipment. The compound is 'This is an amazing material," says Lauf. "You ideally suited for use in standards and other can make a big billet of CBCF, machine it to any components that must be handled frequently shape you want, and it's automatically optically because its optical properties are not affected by black. It's much more robust than any of the surface contact. competing products. You can cut it, file it, or even For applications in which greater structural machine shapes into its surface. Also, because it's strength is needed, CBCF can easily be bonded to carbon, it's not toxic. And it's pretty cheap as a dense graphite backing. Or, if a combination of high-tech materials go." reflection and absorption is needed, such as in CBCF can be used wherever low reflectivity is advanced annular baffle systems used to minimize needed over a wide range of optical wavelengths. unwanted light in telescopes, it can be attached to Examples include liners and baffles for telescopes sheets of reflective metal. and beam stops for laser equipment. In addition, "We'd like to develop other spin-offs of this CBCF can be coated with metal and used as a technology," says Lauf. "Using CBCF as an diffuse-reflectivity standard for calibration and optical absorber is only the frrst." -JimPearce l:m

Number Two, 1992 143 Technical Highlights Weld Analysis Advance at the HFIR

Members of the research team are Camden Hubbard, Stan David, and Tad "The Dodson, all of ORNL's stresses Metals and Ceramics Division; Steve Spooner of formed in a the Solid State Division; and complex three researchers from Chalk River Nuclear multipass Laboratories-J. H. Root, weld as a J. M. Holdens, and result of the J. Schroder. The team used a specially modified welding spectrometer system at the process have High Flux Isotope Reactor (HFIR), built cooperatively been by the Solid State and mapped for Metals and Ceramics the first time divisions. "We have shown that the by a team of HFIR is a valuable tool for scientists understanding the magnitude and distribution of residual uszng stresses in a weldment," says neutron Steve Spooner (left), Stan David, and Cam Hubbard observe a Hubbard. "This knowledge scattering at welded sample whose residual stresses were characterized using is important because large neutron beam scattering. The arrows show the direction in which the tensile residual stresses may ORNL." neutron beam was passed. These ORNL researchers were members lead to catastrophic failure of a team that was first to measure residual stresses in a multipass of a weld in service. Because weld, using a neutron beam from ORNL's High Flux Isotope Reactor. ORNL has a special X-ray facility, the steady-state neutron source offered by e stresses formed in a complex the HFIR, and plans for an Advanced Neutron ultipass weld as a result of the welding Source, ORNL has the capability of becoming a p ocess have been mapped for the first 'residual stress center' that can nondestructively timeT: by a team of scientists using neutron determine whether various materials have scattering at ORNL. A multipass weld is a weld unacceptable levels of residual stress." formed by passing a welding instrument several The stresses were mapped by studying how times and adding filler metal between two metallic the neutrons from the HFIR were scattered from plates to completely join them together. the atoms in a solid weld metal. The mapping Residual stresses are stresses remaining in an was performed on a 30-cm (12-in.) square object when no external force is applied. welded plate of ferritic steel. The sample Knowled{e of residual stresses is very important consisted of two 1.27 em (1/2-in.)-thick steel because when the combination of residual stress plates welded together using a matching ferritic and applied stress exceeds the yield stress of a steel wire and gas tungsten arc welding process. material, the object will likely deform or fail. This multipass weld required about 12 welding

144 Oak Ridge National Laboratory REVIEW passes to completely join the two plates of steel and out into the steel plate where the stresses together. eventually became compressive. Using neutron scattering, the researchers "We found that the tensile stresses approach obtained a three-dimensional map of strains in a the yield stress of the material and may nearly series of "volume elements" in the weld, the heat­ exceed this stress in the weld zone," Hubbard affected zone, and the base metal of the steel says. "If these stresses are not minimized, such plate. Each volume element was several cubic welds could show signs of cracking after millimeters. From the measurements of the exposure to applied loads. These residual strains (which extend along the length, width, and stresses can be reduced in the weld by post-weld, height of each volume element), the researchers stress-relief heat treatments. Our ability to map calculated the residual stresses in each of the residual stresses in welds will allow us to three principal directions. evaluate the effectiveness of such treatments." Stresses (or forces) on a crystalline material Multipass welds are commonly used in many "The HFIR cause lattice strains. The size of a strain can be industries. "Our data," says Hubbard, "will be determined by measuring the distance between useful in predicting the properties of multipass instrument the planes of atoms in the material. In a welds in ferritic plates and will provide a basis could also be crystalline material containing residual stresses, for modeling multipass welds." Hubbard adds used to map compressive stresses cause these distances to that the HFIR instrument could also be used to decrease, and tensile stresses cause them to map residual stresses in industrial objects such as residual increase in comparison with lattice spacings in a ceramic-coated turbine blades or oil well stresses in stress-free material. casings.--Carolyn Krause The scientists irradiated the welded sample industrial with a neutron beam having a ftxed wavelength Book Presents Integrated objects such of 1.65 angstroms, selected to make the scattering as ceramlc­ angle 90° for a stress-free ferritic steel sample. However, when residual stresses exist, the Forest Study Results coated separation between the atomic planes is smaller A landmark book edited by an ORNL scientist turbine or larger than the separation in the stress-free part and a former ORNL staff member contains blades or oil of the sample, so the neutrons are scattered at valuable information for researchers and slightly different angles. From the observed environmental managers. The new book well diffraction angles, the lattice spacings and, examines the effects of atmospheric pollutants casmgs.. " therefore, the strains are determined. on forests and their implications for forest By changing the sample position and using a management and pollution control. One of its special detector to accurately count the neutrons surprising findings suggests that some American scattered at various angles, the researchers forests in the Southeast may be more vulnerable obtained a detailed map of residual stresses in the than those in the Northeast to acidity from the weld sample. The key to their success was the atmosphere. computer-controlled sample stage, beam The book Atmospheric Deposition and collimators, and detector attachment added to the Nutrient Cycling in Forests (Springer-Verlag existing triple-axis neutron spectrometer at the Publishers, New York, 1992) was edited by HFIR. These modifications and this study were Dale W. Johnson, a former ORNL soil scientist made possible by support from the ORNL now with the Desert Research Institute of the Director's R&D Fund. University of Nevada, and by Steven E. In the experiment on the ferritic steel weld Lindberg, leader of the Atmospheric and sample, the researchers found large tensile Geochemical Processes Group of ORNL's stresses parallel to the weld line in the weld metal Environmental Sciences Division (ESD).

Number Two, 1992 145 TECHNICAL HIGHLIGHTS

data obtained make A view of the red possible far-reaching spruce research conclusions, the editors site from the 30-m say, because all sites meteorological were monitored over tower at an the same period, using elevation of comparable instruments 1740 min Great and standardized Smoky Mountains protocols. National Park. The For the first time, the picture was taken following a winter IFS accurately cloud immersion measured the total event, which deposition on forests of bathed the trees in both wet and dry frozen cloudwater pollutants from the known to contain atmosphere. The IFS elevated measurements were concentrations of made using a number of acidity, sulfur, and remote, automated nitrogen. collectors and sensors, some of which were developed at ORNL, that took samples either during precipitation or after it stopped; in this Lindberg was recently elected a fellow of the way, some of the samplers collected rain, snow, American Association for the Advancement of and cloudwater and the others collected only dry Science, which cited him "for outstanding pollutants. According to Lindberg, "The IFS research elucidating mechanisms, pathways, and estimates of the total atmospheric deposition of interactions of atmospheric pollutants in forests acidity far exceed those of the National and for unique creativity in developing techniques Atmospheric Deposition Program, which used only to quantify their biogeochemical cycles." He was rain samplers to collect wet deposition for the the first ORNL scientist specializing in National Acidic Precipitation Assessment atmospheric and hydrospheric sciences to be Program." named an AAAS fellow. The primary goal of the IFS was to determine The book is a detailed synthesis of the recently the effects of atmospheric deposition of sulfur and completed Integrated Forest Study (IFS), which nitrogen oxides, acidity, and ozone on the was begun in 1985 and was an interdisciplinary movements and availability of nutrients that trees project involving experts in the atmospheric, take up from forest soils. These nutrients include ecological, and soil sciences. IFS studies were nitrogen, phosphorus, sulfur, potassium, calcium, carried out at 17 forest research sites in Canada, and magnesium. Norway, and the United States-specifically, in Ions of some of these nutrients can be replaced Tennessee, North Carolina, Georgia, Florida, at their soil sites by ions from deposited Maine, New York, and Washington. ORNL atmospheric acids, making these leached nutrients scientists designed the project, obtained the unavailable to trees as they are washed away in funding, and managed the work of more than soil water. Another element of interest is 50 scientists representing 25 institutions and aluminum, a toxic metal found in the soil. It can be universities in North America and Europe. The made available for uptake by trees if the soil

146 Oak Ridge National Laboratory REVIEW becomes acidified by the deposition of sulfate and aluminum in soil solution, decline of the loblolly nitrate. pine forest around Oak Ridge is deemed unlikely. "The IFS findings," says Johnson, "could One of the outside reviewers who praised the improve the accuracy of forecasts of nutrient book said, "This synthesis has provided deficiencies in forests that may result from convincing evidence of many issues in atmospheric deposition or harvesting." atmospheric deposition, and it will be an important text for years." Among the important findings of the IFS study Although completed in 1989, the IFS has are these: resulted in spin-off research projects at ORNL and elsewhere. Sandy McLaughlin of ESD built on • Atmospheric deposition of acidity, sulfate, and IFS findings in his proposal of continued studies nitrate was greatest at the high-elevation sites of the effects of aluminum and calcium on the affected by cloudwater. It was higher in the physiology of spruce trees in the Smoky southeastern United States (e.g., Smoky Mountains. Helga Van Miegroet and Chuck Mountains) than in the Northeast (e.g., Garten have received ORNL seed money to use Whiteface Mountain in New Hampshire). This nitrogen isotopes to determine the critical sources "Clearly, the finding is unexpected and could not have been and sinks for atmospheric and soil nitrogen in IFS results revealed by traditional bulk collector Smoky Mountain forests. Supported by the U.S. measurements. Forest Service and the National Park Service, continue to Lindberg and Jim Owens have designed and influence • Except perhaps for mountain forests, acidic conducted a study of sulfur deposition on forests deposition combined with ozone exposure is at different elevations on Clingmans Dome. future unlikely to cause tree leaves to lose significant "Because of the IFS findings in the Smokies," research on amounts of their nutrients. says Lindberg, "the National Park Service has the effects of committed to establishing a long-term air • Deposition of sulfate and nitrate has increased pollution, water quality, and forest health air pollution the rate of nutrient leaching from most of the monitoring study near the IFS site on Clingmans on forests." forest soils at IFS sites by 20 to 60%, making Dome. Clearly, the IFS results continue to these nutrients unavailable for use by trees and influence future research on the effects of air forest vegetation. Levels of potentially toxic pollution on forests ."--Carolyn Krause aluminum rose in the most acidic soils.

• Atmospheric deposition may have contributed to New Electron Microscope the declining health of some red spruce stands in the Smoky Mountains, particularly Clingmans Images Show How Dome, by increasing the leaching of both nitrate Superconductors Grow and aluminum from the soil. As a result, nitrate l.evels increase in streams and aluminum High-temperature superconductors can be made becomes more available for uptake by trees (in by using lasers to deposit films on a substrate, one preference to the nutrient calcium) and for atomic layer at a time. But the ability of the transport to streams, where it can harm fish. superconductor to carry useful amounts of electrical current depends on its structure, and According to the IFS, an Oak Ridge loblolly achieving the best microstructure could require pine site is considered vulnerable to total nutrient some fine-tuning of the film deposition process. leaching by deposited acids because its highly Steve Pennycook ofORNL's Solid State weathered soils are low in minerals that could Division has developed an imaging process using neutralize these acids. However, because of the an electron microscope that can reveal in detail high tolerance of loblolly pine to leached how the individual atomic layers of

Number Two, 1992 147 TECHNICAL HIGHLIGHTS

islands. Knowing the details of how these films grow helps us determine and control the microstructure to improve the ability of the film to carry current." The films are actually "superlattices," alternate layers of superconducting and insulating materials on a magnesium oxide substrate, which serves as a template to properly align the first layer of deposited atoms to obtain the desired microstructure. The superconducting layers are made of an oxide of yttrium, barium, and copper (YBCO). The insulating layer is composed of an oxide of This micrograph made by Z-contrast electron microscopy provides barium, copper, and the rare details on how the individual atomic layers of superconducting and earth praseodymium. insulating material actually grow. Such information is crucial for Pennycook says that an researchers trying to make superconducting films that have an improved island of YBCO is six atomic ability to carry current. Shown here in the outlined darker area is a layers high, the height of the superconducting layer made of an oxide of yttrium, barium, and copper smallest possible amount of (YBCO) sandwiched between two insulating layers, composed of an YBCO, known as one unit oxide of barium, copper, and the rare earth praseodymium (PBCO). The cell. The typical island is 50 interface shows the remarkable roughness, on the scale of the individual unit cells (vertical stripes), that developed as a result of rapid deposition. unit cells long. "This material likes to be flat," he says, "and most of its energy is directed superconducting and insulating material actually toward spreading it out." grow. This information is crucial for researchers Pennycook's special imaging process uses a 100- trying to make superconducting films that have an kilovolt scanning transmission electron microscope improved ability to carry current. (STEM) and a ring-shaped detector to detect Pennycook says his imaging process is the only electrons scattered at large angles after they electron microscopy technique that reveals "the penetrate the sample (rather than those passing fossil record" of the growth process by which straight through it). This "Z-contrast" imaging superconducting films are formed. It enabled him process, which images atoms directly, is so named to discover that the deposited material forms because atoms having the highest atomic number "islands" that eventually combine into a smooth (number of protons, or Z) scatter more electrons layer upon which new islands form to make the and, therefore, are seen as bright, whereas the next layer, and so on. Pennycook reported his lighter atoms are shown as gray or black. findings in an invited talk at the 1992 spring "Z-contrast electron microscopy gives a direct meeting of the Materials Research Society in San view of materials on an atomic scale," Penny cook Francisco. says. "It reveals previously unknown atomic "Our technique," he says, "is the only one that arrangements, and the relative brightness of each shows the size, shape, and rate of growth of the atomic column indicates composition. It gives us

148 Oak Ridge National Laboratory REVIEW snapshots of each superconducting layer and can With the new capability, Pennycook will obtain reveal problems in layer structure, such as surface sharp images not only of the barium atoms but also roughness_." of the yttrium and copper atoms in YBCO. He Because barium atoms are the heaviest in plans also to extend these studies of growth YBCO, they are bright white in Z-contrast mechanisms to other materials, including micrographs; however, in images of both the semiconductors, metals, and ceramics.--Carolyn insulating and superconducting layers, Krause praseodymium is the brightest of all imaged atoms because it is the heaviest element present. In some ofPennycook's images, the barium atoms resemble ORNL Researchers the vertebrae in an X ray of part of a human spinal column. Other images show steps between layers Cultivate Biomass of YBCO unit cells, a record of the presence of Energy Program islands at that stage of the film 's growth. The details of film growth obtained by For thousands of years, trees and grasses have Pennycook help Douglas Lowndes and his Solid been burned to produce heat. But only recently "With the State Division associates determine how to alter have scientists recognized that large-scale laser ablation to obtain superconducting films that cultivation of trees and grasses could meet a new can carry useful amounts of electrical current. significant portion of the country's future energy capability, Laser ablation is a technique in which bits of needs. superconducting material are evaporated and Growing concern over increased levels of carbon Pennycook deposited in a controlled way as a layered film on a dioxide in the atmosphere, resulting from burning will obtain substrate. fossil fuels, and their effect on global warming has sharp images Pennycook's images indicate whether they aroused considerable interest in biomass crops. should consider changing the oxygen pressure, 1anet Cushman, a staff member of ORNL' s not only of temperature, and rate of film deposition to improve Environmental Sciences Division and manager of the barium the film microstructure. "If the material is DOE's Biofuels Feedstock Development Program, deposited too fast, there is less time to form islands, said when biomass crops are burned for energy, the atoms but and the growth mode changes," Pennycook says. carbon dioxide produced is merely the recycled also of the "Increased surface roughness may result, causing carbon dioxide removed from the atmosphere yttrium and short circuits in device structures." during plant photosynthesis, "a vast improvement One of the results of the collaboration between over emitting carbon dioxide from fossil stores as copper Lowndes and Pennycook was the discovery that you do when coal and oil are burned." atoms in making a "superlanice" by depositing two layers Cushman said biomass is an especially promising YBCO. " (instead of one) of a superconducting material option for reducing carbon dioxide emissions from between each pair of insulating layers results in a transportation systems because it is the only film that is better able to carry electrical current renewable energy source that can produce liquid without losing its superconductivity. fuels, such as methanol and ethanol, for vehicles. Pennycook's imaging capability will improve "All the others- hydroelectricity, direct solar, dramatically later this year with the installation of a geothermal, and wind-produce only electricity or newly built 300-kilovolt STEM. This technology heat," she said. The main obstacle to the will allow him to achieve a resolution of widespread use of biomass-derived fuels has been 1.3 angstroms, the highest direct resolution in the their cost. However, by developing more world. With his current microscope, he can easily productive crops and by continuing to decrease image a YBCO unit cell, which is 12 angstroms production and conversion costs, ORNL high, and a layer of barium atoms, about researchers believe biomass-derived ethanol costs 2 angstroms high. An angstrom is about one could be lowered to 60 to 70 cents per gallon millionth the diameter of a human hair. within the next 5 to 10 years, a price competitive

Number Two, i 992 149 TECHNICAL HIGHLIGHTS

Helga Van Miegroet, a soil scientist in ORNL's Environmental Sciences Division, samples soil water for nutrients on the Oak Ridge Reservation. She is evaluating four different nitrogen fertilization regimes in a short­ rotation sycamore planting to identify the regime that produces the best tree growth.

with $25-per-barrel oil. In this way, biomass fuels Lynn Wright, deputy manager of the Biofuels could reduce U.S. dependence on unreliable Feedstock Development Program, said that supplies of foreign oil. considerable information about the procedures Biomass research was first sponsored by DOE needed for successful tree farming-site after the oil crises of the early 1970s. The original selection and preparation and a variety of weed­ goal of the research was to increase the control measures--<:ame from this silvicultural productivity and lower the cost of growing and research on about 25 species. ORNL has also harvesting woody plants for energy uses. In 1978, supported successful research in genetic DOE's Biofuels Feedstock Development Program improvement and tissue culture. "In fact," began working with universities and agricultural Cushman said, "essentially all the facilities across the country to identify the tree noncommercial hardwood tissue culture research species most appropriate for biomass fuel crops being done in the United States now is funded and to select the types of land most suitable to through this program." cultivate those crops. Of 140 tree species screened In 1984 DOE expanded the scope of its energy by 1986, six were targeted as models-poplar, crop research to include nonwoody, herbaceous eucalyptus, black locust, sycamore, sweetgum, and plants that could supplement woody crops. silver maple. Cushman said the original idea was to compare

150 Oak Ridge National Laboratory REVIEW nonwoody species and to select the best for Wright said it is also important to have a strong development. However, the researchers soon scientific understanding of the environmental realized that different non woody species are best issues related to biomass crop development. "Of for different situations. "A suitable grass crop can course, environmental issues depend on who be developed for any kind of land that becomes you' re talking to. If you're from an agricultural available for energy feedstock production," she said background, you want to know that soil "and grass crops can also be grown and harvested productivity can be maintained," she said, noting with standard farm equipment, which lowers the that some people looking at biomass from an cost for interested farmers." Annual crops can be environmental standpoint consider the habitat and used in rotation with conventional agricultural biodiversity issues to be most critical. "Some crops. Perennial crops form dense stands that can groups are concerned that if new markets are "If we can protect erosion-prone soils. Legumes can fix created for agricultural products, additional nitrogen, reducing fertilizer use. All of these types cropland might be cleared, encroaching into develop fuel of crops could have a place in energy production. sensitive habitats, like wetlands or stream crops that After National Energy Strategy activities in 1991 , buffers," she said. To address those issues, such produce an DOE proposed an aggressive biofuels initiative groups as the U.S. Environmental Protection with a goal of having a proven technology for Agency and the Audubon Society are assessing average of producing ethanol from plants' cellulosic policy options that would encourage /0 dry tons materials- not just the starchy parts of the grain environmentally acceptable, large-scale biomass now being used-by the year 2000. energy systems. per acre, we Cushman believes that to arrive at this target, Wright said another environmental concern is could several pilot-scale facilities that process between 40 the chemicals needed for energy crops, even ultimately and I 00 tons per day, 300 days per year for 2 years though they require fewer chemicals than will be needed, so the facilities must be operational traditional food crops. "The trend is to use fewer supply half no later than 1998. "And if genetically improved chemicals," she said. "We're learning when and the country's trees are to be a part of the project, they must be how to apply chemicals conservatively-in planted by 1992, since in most parts of the country narrow strips, for example, rather than broadcast transportation it takes six years to grow a tree," she said. over the entire site." fuel needs on "We've received several calls from people Wright believes the amount of readily available 125 million interested in biofuels crops. In California there is cropland will continue to increase. "Given interest in putting together a consortium of farmers predictions that in the future more crops will be acres." and industries. And in Minnesota, several groups produced on less land and that export demands have already been thinking about what it would will decline, then less land will be needed for food take to get dedicated energy crop production crops," Wright said. " If we can develop fuel crops facilities going," Cushman said. Enthusiasm is that produce an average of 10 dry tons per acre, clearly building. The next step is to develop the we could ultimately supply half the country's needed support. transportation fuel needs on 125 million acres. Besides the environmental value of carbon Although these goals are very optimistic, research dioxide recycling, Wright reported that biomass could make them achievable within 30 to 40 crops offer other benefits. "A lot of cropland is years." easily eroded. If we could plant perennial grasses or ORNL researchers make a point of keeping all trees on that land, it would reduce soil loss and at the groups involved in this research talking to the same time offer an economically viable crop for each other. Cushman believes this is one reason farmers," Wright said. Biomass crops also offer the program has been so successful. "Even though economic benefits to the United States by reducing most of the crop development research takes place dependence on foreign oil and by providing at different universities and agricultural facilities, alternative crops that could boost the nation's farm we feel it's crucial to have a strong central economy. organization that keeps people talking and that

Number Two, 1992 151 TECHNICAL HIGHLIGHTS

cuts across state, regional, and institutional on the ATF and magnetic fusion research at boundaries," she said. As an example of fruitful ORNL, see the Number Four, 1987, issue of the interaction, researchers from ORNL and the Review. ) National Renewable Energy Laboratory of Since it started operation in January 1988, the Golden, Colorado, are working together on a ATF has had a distinguished history. The ATF ' s project to examine the chemical changes that take unique design allowed creation of a wide range of place in biomass crops during storage and how plasma configurations for study of fundamental these changes might affect the quality of the physics issues relevant to both tokamaks and alcohol produced. stellarators. "The ATF America's farmlands have long been considered During the first year, A TF researchers studied a researchers the breadbasket of the world. And within the next regime of plasma operation that has the potential few years, if ORNL researchers are successful, for confiDing plasma having more energy content have also these farmlands may also become known as an for a longer time at a given magnetic field strength. made important energy resource for the nation.-Karen An unexpected magnetic field perturbation had Bowdle allowed access to this "second-stability" regime at significant much lower power than had been otherwise contributions ATF Experiment needed. to After compensating for this field perturbation, Under Repair ATF researchers studied other basic confmement understanding physics issues including the "bootstrap current," an confinement ORNL's Advanced Toroidal Facility (ATF), internal self-generated current in toroidal plasmas the world's largest fusion experiment of its type, that must be maximized in tokamaks and in toroidal ceased experiments on November 15, 1991, after minimized in stellarators for optimum plasmas." nearly four years of operation (and over 20,000 performance. The ATF group found that its "plasma shots"). The $20-million ATF is a experimental measurements of this current agreed stellarator, which, along with the better-known with theoretically predicted values, giving tokamak, belongs to the family of toroidal confidence that the bootstrap current can be used (doughnut-shaped) confmement devices that for optimizing future tokamak and stellarator dominate modem controlled fusion research. designs. Fusion energy is produced by fusing high­ The ATF researchers have also made significant energy nuclei of hydrogen isotopes. Magnetic contributions to understanding confmement in fields can be used to confme these nuclei in a hot toroidal plasmas. Comparison of measured ionized gas, or plasma. In this way, loss of plasma fluctuations in the edge-plasma parameters in the energy to the vessel wall is substantially reduced. A TF and in a comparably sized tokamak allowed It is predicted that an improved toroidal device researchers to gain a better understanding of the that effectively confines a fusion plasma could role of these fluctuations in causing deterioration lead to a practical source of electricity by the in plasma confinement. These studies have been middle of the next century. extended to the plasma core in the A TF in a The ATF stellarator (shown in the figure) uses collaborative experiment between ORNL scientists helical windings to create the magnetic field that and researchers from the Institute of General contains and stabilizes the plasma used in Physics in Moscow. Results of preliminary experiments; the circular coils position and shape analyses show evidence of a particular plasma the plasma. By contrast, for plasma confmement instability that was sought in this experiment. the t~amak requires a plasma current that must Throughout its history, the A TF program has be driven for steady-state operation. Other featured collaborations of this type with U.S. comparably sized stellarators operate in Germany, universities and fusion laboratories in Japan, Spain, Japan, and Ukraine. (For background information Russia, Ukraine, and Germany.

152 Oak Ridge National Laboratory REVIEW OUTER VF COILS

VACUUM VESSEL PORTS

1 Schematic of the ) Advanced Toroidal Facility.

SUPPORT COLUMNS

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• BASE DIAGNOSTIC AND UTILITY PENETRATIONS :-==~7F :-=-= -==-~ L ~ Advanc:ed Toroidal Facilit y Oak Ridge Nat100at Lat:>Oramry

Although the A TF was developed as an operation to the long-pulse, steady-state regime experiment to test optimization principles and for which the device was designed. Whether this steady-state operation, budget restrictions have restart occurs depends on a review of the U.S. prevented the ORNL stellarator from reaching its fusion program strategy now under way. full potential. A DOE decision in late 1990 to Encouraging support from the U.S. fusion focus on tokamaks altered the A TF research community and from DOE gives reason for program and resulted in operation of the A TF at a optimism that the A TF program will restart in reduced level in fiscal year 1991 and a plan to 1993.-James F. Lyon, ORNL' s Fusion Energy mothball it in fiscal year 1992. Division At the end of May 1991, an electrical short caused extensive damage to part of one of the large helical windings shown in the schematic ORNL Wins Four above. A limited repair was implemented, and the R&D 100 Awards ATF resumed operation on September 25 , making it possible for the ATF group to accomplish most In the fall of 1992, four ORNL developments of the goals planned for the summer of 1991. received R&D 100 Awards from Research & The ATF is currently being repaired to preserve Development magazine. The magazine's editors the option of restarting the A TF program. In selected these developments to be on their list of addition, the A TF group hopes to double the the top 100 new technology advances in the plasma heating on the A TF and to extend world.

Number Two, 1992 153 TECHNICAL HIGHLIGHTS

The winning entries were ion implantation to molecules by firing new atoms in the form of produce hard-surfaced polymers, a method of positive ions into the polymer's molecular matrix. accurately blending new compounds with ozone­ The new structures created through this process depleting chlorofluorocarbons (CFCs) in air couldn't be achieved using traditional polymer conditioners and refrigeration units to cut down on processing techniques because they don't rely on the use of CFCs, the surface-enhanced Raman normal chemical reactions; instead, the ions are optical data storage system, and a computer wedged into the polymers' molecular structure by technology for identifying the genes in sequences sheer force. "The ability to create new materials of genetic information. that cannot be synthesized by conventional Since 1967 when the Laboratory first entered the chemical means," says Mansur, "opens up entirely competition, ORNL has received 69 R&D 100 new areas of materials science and engineering." Awards (originally called I•R 100 Awards) and This violent union produces new materials, Energy Systems has received 79, placing Oak often having physical properties far different from Ridge first among DOE sites in this competition. those of the original polymers. "Part of our work is looking at the atomic and molecular basis of the John Henry could have been a polymer­ changes in the properties of these materials," says drivin' man. According to song and story, Lee. "Another part is applying what we've America's hammer-swinging, spike-pounding learned." railroad builder, John Henry, was a "steel-drivin' During the studies, polymers are implanted with man." Of course, that's only because he didn't boron, carbon, silicon, and iron ions by the TIF have the benefit of recent developments at facility's three accelerators using either single ORNL's Triple Ion Irradiation Facility (TIF). If he beams or two or three beams simultaneously. The had, he might have traded in his steel spikes for a use of multiple beams produces reactions not only set made of ion-implanted Kapton, a light, durable between the beams and the target, but also polymer with a surface that is three times as hard between the ion species of the beams themselves. as stainless steel. This approach yields different, and in some cases Created using TIF's three accelerators, this better, results than using the three beams potentially revolutionary material, along with other separate Iy. "hard-surfaced" polymers, is the brainchild of Eal To determine the effect of the ion treatments, Lee, Monty Lewis, and Lou Mansur, researchers in the implanted materials are analyzed using a ORNL's Metals and Ceramic~ Division. Polymers number of techniques, including microscopic are chemical "strings," or linear combinations of methods, hardness and wear testing, X-ray repeating molecules used in a variety of products, analysis, and Raman spectroscopy. from soft drink bottles to machine gears. The primary effect of high-energy ion-beam Most ion-beam surface modification research has processing on polymers is to produce materials been aimed at improving the physical having an increased number of interconnections characteristics of semiconductors, metals and between molecules in all three dimensions. This ceramics to broaden their applications. The use of increased molecular interaction often results in polymers in severe environments has been limited several enhanced surface features, such as by their inherent softness and poor resistance to wear, abrasion, and other factors. Researchers hope Hardness. Depending on the type of ion beams to overcome these traditional weaknesses by using used, ion implantation studies at ORNL have ion implantation to combine the most useful produced polymers that are 13 to 41 times as hard features of polymers, such as light weight, as their untreated counterparts. flexibility, and corrosion resistance, with the hardness of metals and ceramics. Wear resistance. Improvement of wear resistance To accomplish this, ORNL researchers are varies with the polymer-ion beam combination trying to increase the number of bonds between used. The most impressive increase in wear

154 Oak Ridge National Laboratory REVIEW Eal Lee peers into the Triple Jon Irradiation Facility's target chamber where as many as three ion beams are simultaneously focused on a polymer target. This process inserts new atoms into the polymer's molecular matrix, creating materials that cannot be made using conventional chemical means.

resistance resulted when samples of Kapton were much material to oxidation as ion-beam-treated treated with single or multiple beams of boron, Kapton. nitrogen, and carbon ions. These samples showed no signs of wear in abrasion tests with a nylon Chemical resistance. Untreated samples of ball; tests with a chromium-steel ball produced a Lexan and polystyrene dissolve in benzene, but high degree of wear on the ball and scratches on treated samples do not. the polymer surface. Conductivity. Implanting certain polymers with Surface smoothness. Ion-beam treatment metal ions increased their electrical conductivity generally produced a much smoother surface when by a factor of 10 10• compared optically with an untreated surface. Wear-resistant polymers could be used to Oxidation resistance. When exposed to an manufacture high-speed moving parts and oxygen plasma, untreated Kapton lost six times as lightweight, load-bearing components. Polymer

Number Two, 1992 155 TECHNICAL HIGHLIGHTS

films can be applied to any surface and ion-beam linked to a variety of ailments, including skin treated, producing hard, wear-resistant protective cancer. coatings. Ion beam processing also improves To combat the problem of ozone depletion, resistance to oxidation and chemical attack, beginning in 1993, the use and production of suggesting that hard-surfaced polymers may be CFCs in the U.S. will be drastically curtailed. The useful in low-earth orbit, where atomic oxygen good news is that researchers have found ozone­ severely erodes traditional polymers. safe substitutes for CFCs. The bad news is that An important ftnding of the project is that the these chlorine-free replacement gases, called degree of molecular interaction of the treated hydrofluorocarbons (HFCs), aren't compatible polymers is closely correlated with their hardness, with the existing systems, so they can be used indicating that ion implantation has increased the only in new ones. carbon content of the backbones of the polymer So, what can be done with existing systems molecules, producing a more rigid structure. when they need to be recharged with refrigerant? Spectrographic analysis of the samples conftrrned Well, the good news is that several mixtures of that ion-beam treatment increases the number of HFCs and CFCs have been developed that are new bonds between molecules. Because the both easier on the ozone than CFCs alone and degree of hardness is dependent upon the type of compatible with existing systems. Since CFC/ ions implanted, new types of bonding, not present HFC blends are being developed for use in in the untreated material, are thought to play an automobile air conditioners over the next few important role in increasing hardness. years, it will become increasingly important to Currently, ion-implanted polymers are still identify the kinds of refrigerant used because considered high-tech materials, and their cost of charging these devices with the wrong kind of production is too high for the mass market. This refrigerant could cause irreversible damage. Also, will limit initial applications to high-value-added the refrigerants must be mixed at specific ratios to products and critical components; however, costs function effectively. Unfortunately, some could come down as demand increases. compounds in the mixture are more likely to leak Other technologies, such as oxide coating and from the system than others. So, the bad news is mineral treatments have been used in the past to that, in order to get the correct mixture, either the improve the surface properties of polymers, and ratio of gases present in the system must be more recently, ultraviolet-cured, scratch-resistant known before it is recharged, or the refrigerant polymers have come onto the market. However, must be replaced entirely. no commercially available product comes close to Traditional methods of determining this ratio the hardness achieved by ion-beam processing at include analyzing a sample of the system's ORNL. contents in a gas chromatograph or an infrared spectrometer. However, the high cost of this Now, just imagine what Paul Bunyan could equipment and the need for specially trained have done with a hard-surfaced polymer axe .... operators rule these options out for most air conditioning or refrigeration repair contractors. To CFC/HFC ratiometer eases move to ozone­ make this capability more widely accessible, Fang friendly coolants. Chlorofluorocarbons, or CFCs, Chen of ORNL's Energy Division and Steve are gaseous compounds commonly used in Allman and Winston Chen, both of the Health and automotive, industrial, and residential air Safety Research Division, have developed a CFC/ conditioning and refrigeration systems. When HFC ratiometer, which is capable of identifying CFCs are released or leak from these systems, the refrigerants present in a given sample and some of them eventually make their way into the determining the concentration of each component upper atmosphere, where they break down the when mixtures are used. layer of ozone that screens out sunlight's This instrument takes advantage of differences ultraviolet rays. Overexposure to these rays is in the electron drift velocities of different gas

156 Oak Ridge National Laboratory REVIEW mixtures in an electric field. That is, under certain conditions electrons travel much more rapidly through some gases than others-at a characteristic rate for each gas. To determine the Fang Chen drift rate for a particular demonstrates the mixture of gases, a sample CFC/HCF is drawn into the ratiometer, a ratiometer, where an device which may electric field is applied to ease the transition the mixture. Then a flash from the ozone­ from an ultraviolet light depleting chloroflurocarbons source causes a beryllium used in most air plate to produce low­ conditioning and energy electrons to drift a refrigeration units known distance across an to environmentally electric field. safer coolant "Depending on the blend blends. of materials," says Chen, "the speed of the electrons will be retarded by a given amount compared to electrons moving through air." The ratiometer then compares these data to that gathered from analyses of known gas mixtures to determine the composition of the sample. principle that the enhanced light-emitting "We envision that the fmal product will be a properties of certain molecules embedded in an briefcase-sized device that is lightweight, optical medium can be altered at the molecular relatively inexpensive-about $1000- and easily level to store information. used by an auto mechanic or refrigeration The SERODS system can achieve l terabyte technician," says Chen. "And because this (1012 bytes) of storage capacity in a 12-in. disk, instrument is designed specifically for thus achieving about I 00 times greater storage refrigerants, results can be obtained immediately capacity than other conventional optical storage without complex data analysis." systems. For example, a 12-inch SERODS disk could store 18,000 sets of the Encyclopedia SERODS could hold 18,000 encyclopedias on Britannica, or 450 million pages of text. a CD. The surface-enhanced Raman optical data Several organizations in both government and storage (SERODS) technology, which was private industry have expressed interest and are developed by Tuan Vo-Dinh of ORNL's Health pursuing licensing agreements for using SERODS and Safety Research Division and David L. technology for supercomputer memories, health Stokes, a University of Tennessee graduate care (e.g., medical data banks for hospitals and student, may have large computer memory medical imaging), space satellite data storage for applications. It is based on the recently discovered global environmental studies, integrated data

Number Two, 1992 157 TECHNICAL HIGHLIGHTS

optical disk or a three-dimensional multilayer optical storage medium. A sample SERODS optical disk contains a plastic or glass substrate The surface­ covered with silver-coated polystyrene enhanced Raman optical data microspheres and an optical layer containing storage light-emitting molecules. When they are close to (SERODS) such a surface, molecules in the optical layer system, developed interact with its microstructures, causing the by Tuan Vo-Dinh molecules to scatter more and emit what is known (left) and David L. as surface-enhanced Raman light. Stokes, achieves A writing laser is used to encode bit about 100 times information by altering the light-emitting the storage properties of specific clusters of molecules on the capacity of conventional disk while leaving other molecules intact. A optical storage reading laser excites all the molecules in the systems. A 12- optical layer, inducing specific microregions of inch SERODS the disk to produce altered light signals and disk can store 450 unaltered signals that correspond with "one" bits million pages of and "zero" bits, respectively. A photometric text. detector tuned to the frequency of the Raman emissions is used to retrieve the stored information (for details, see "Technical Highlights," ORNL Review, Vol. 23 , No. I, 1990, p. 85).

storage systems for "paperless" navy ships, and GRAIL separates genetic wheat from chaff. entertainment (optical disks for movie rental ln ancient times, kernels of wheat for making companies). flour were gathered by hand-a slow and "The ORNL system could be used for virtually inefficient process. Then, an innovative approach any activity requiring large-memory data was developed. First, the grain was crushed to storage," Vo-Dinh said. "Examples are archive loosen the kernels of wheat from their husks, or storage for the insurance industry, data banks for chaff. Then this mixture of wheat and chaff was financial firms and banks, global data storage for thrown into the air. The slightest breeze would the proposed U.S. orbiting space laboratory of the blow the light chaff to the side, and the heavier National Aeronautics and Space Administration, wheat would fall down in a pile. optical archives for the Library of Congress, and Genetic researchers face a similar dilemma as DNA information storage for the Human Genome they try to separate areas of biologically relevant Project." information from the rest of the sequence of DNA SERODS is the only system available that bases that makes up the human genome. What offers three-dimensional data storage for makes their job even more difficult is that about replacing conventional two-dimensional disk 95% of the genetic information they look at is surfaces, thus greatly increasing data storage chaff. Only 3-5% of the DNA bases contain capacity. It also provides protection for sensitive instructions for manufacturing proteins, the and proprietary information because such data can molecules that govern the chemical processes be accessed only if the frequency of the vibrating necessary for life. molecules used for the optical layer is known. Not surprisingly, developing the technology to The SERODS system uses a writing laser, a locate genes in DNA sequences is a primary goal reading laser, a photometric detector, and an of DOE's Human Genome Project. This challenge

158 Oak Ridge National Laboratory REVIEW has been largely met by ORNL researchers through the construction Richard Mural and of the Gene Recognition Ed Uberbacher work at a GRAIL and Analysis Internet terminal. The Link (GRAIL) system. system employs Ed Uberbacher, Reinhold neural networks to Mann, and Ralph simulate the Einstein of the function of neurons Engineering Physics and in the brain as it Mathematics Division "learns" to and Richard Mural and recognize the Xiaojun Guan of the characteristics of genes in a DNA Biology Division have sequence. integrated biological insight about genes and the proteins they code for into this state-of-the-art, computer-based artificial intelligence system. Using neural networks, which simulate the function of neurons in the brain, and other intelligent machine principles being developed at ORNL's Center for prenatal diagnosis of the disease. The degree to Engineering Systems Advanced Research, GRAIL which these relevant portions of the genome can "learns" to recognize the characteristics of genes be identified and understood will largely in a DNA sequence. Combining the information it determine whether knowledge of the human gathers from examining known genes with genome can be applied to problems in biological knowledge provided to it, GRAIL biotechnology, gene therapy, and the development develops principles that it uses to locate new of pharmaceuticals-technologies which are genes. Each party contributes expertise in this based on the manipulation of genes and their partnership between human and machine, protein products. resulting in new insights into the problem of gene About 400 biotechnology companies and recognition. research laboratories currently use GRAIL to The system is already being used to analyze the analyze DNA sequences, primarily to locate genes DNA sequence for the genes responsible for that may play a role in human disease or have Huntington's chorea, various muscular applications in medicine, biotechnology, or dystrophies, and a number of other genetic pharmaceuticals. In the long term, it is likely that diseases. Once the gene or genes responsible for a gene therapies or cures for some of the thousands particular disease have been located and analyzed, of genetic diseases that affect humans will be the potential exists for the development of genetic developed from genetic insights provided by screening tests for prospective parents and GRAIL. 1!11

Number Two, 1992 159 Technology Transfer ORNL Expertise Used in 30 CRADAs

(SF }-an insulating gas used in Maureen Baker 6 counts the number circuit breakers, transformers, of Chinese switchgear, and underground hamster ovary electrical transmission lines-is cells that survived being studied under a CRADA exposure to involving ORNL, the National sparked sulfur Institute of Standards and ), hexafluoride (SF6 a commonly used Technology (NIST), and Ontario insulating gas. By Hydro (a Canadian electric power combining utility). biological testing The compound, disulfur with chemical ) , decafluoride (S2F 10 was found to be analysis, ORNL toxic in cell cultures grown at researchers ORNL, was shown to cause lung determined that damage in animals, and is believed disulfur decafluoride, to cause lung damage in humans. which is formed in Exposure to decomposed SF6 can be , hazardous to human health, as sparked SF6 is responsible for indicated in the September-October the toxicity of the 1991 issue of Electrical Review. In sparked gas. an article entitled "JET Workers Lucky To Be Alive," it was reported n the two years since August 1990, that two men who had been exposed to

Energy Systems has entered into 37 decomposed SF6 at the Joint European Torus, a cooperative research and development fusion research facility in England, developed I pulmonary edema. The compound or compounds agreements (CRADAs). Of these, 30 take advantage of ORNL expertise. responsible for this effect were not unequivocally CRADAs are designed to foster cooperative identified. research between industry and government ORNL research participants in the CRADA are laboratories by offering private firms Isidor Sauers and Guy Griffin, both of the Health advantageous rights to patents and other and Safety Research Division, and Randy James, intellectual property from the joint research, who is providing technical program management trade-secret-like protection of joint data, and through the Power Systems Technology Program in streamlined government approval of the the Energy Division. Sauers, who was the first to

agreement. measure the amount of Sl10 produced in a given volume of SF , will develop a sensitive method Several of the CRADAs not previously 6 highlighted in the Review are described on the employing cryogenic enrichment-gas following pages. chromatography techniques for detecting low • levels of the toxic compound in SF6 (Sauers has Study of toxic by-product in insulating gas. also collaborated with NIST in developing another The significance of the presence of an extremely sensitive technique, using gas chromatography­ toxic by-product in an electrical insulating gas, mass spectrometry, that measures constituents of which was first revealed by ORNL studies, is the gases at parts-per-billion levels.) Griffin, the first to

subject of a CRADA signed by Energy Systems in show that the toxicity of sparked SF6 was chiefly a , October 1991 . The toxic compound formed by result of the presence of S2F 10 will further study electrical decomposition in sulfur hexafluoride the gaseous by-product's toxicity.

160 Oak Ridge National Laboratory REVIEW "Although S2F 10 has been found in the laboratory, we do not know if it exists in actual power equipment," James says. "Utilities, government agencies, and manufacturers are interested in the results of this CRADA because the safe operation and maintenance of circuit breakers and other electrical equipment using SF 6 are important to them." In a recent talk, Griffin said, "Our biological testing led us to discover the presence of in "Although Sl10 SF • In 1980 I exposed Chinese hamster lung cells 6 S F has and Chinese hamster ovary cells to sparked SF 2 10 6 and found that 86% of them died. Then I exposed been found them to SF6 alone and known by-products of in the electrical discharges in SF , such as SOF , SOF , 6 2 4 laboratory, , , ... S02F2 and S02 and discovered that none of these products singly or in combination with the others we do not was as toxic as sparked SF • 6 know if it "This fmding suggested that an unknown by­ product was responsible for the toxicity. So in In the control experiment (left), most Chinese exists in 1985- 86 Isidor Sauers worked on identifying the hamster ovary cells survived exposure to sulfur actual power hexafluoride, but virtually none survived exposure toxic product. When we found that heating a to disulfur decafluoride, a decomposition product equipment." sample of sparked SF eliminated its toxicity, we 6 of sparked sulfur hexafluoride. had indirect evidence of the presence of S F 2 10 because S2F 10 decomposes upon heating, whereas most of the other breakdown products of SF are gas is withdrawn from electrical equipment during 6 stable at temperatures below about 300'C. repairs; and (5) disseminate information and "Using the techniques of gas chromatography," transfer relevant technology. OSHA has delayed

Griffin added, "Sauers detected a significant enforcement of the 10-part s-per-billion Sl10 amount of S2F 10- about 260 parts per million- in ceiling limit until a suitable detection method is • developed, tested, and approved. a sample of sparked SF6 Our later biological studies showed that S2F 10 is orders of magnitude The CRADA project will receive $1.8 million more toxic than the other by-products in sparked over three years from the DOE Office of Energy ." SF6 Management, the Electric Power Research The goals of the CRADA are to (1) study the Institute, Ontario Hydro, Empire State Electric formation and destruction mechanisms of S F , its Energy Research Corporation, and the Canadian 2 10 stability, thermal and chemical properties, and its Electrical Association. The Bonneville Power toxicity under a variety of conditions; (2) develop Administration and the Tennessee Valley sensitive techniques to detect the toxic compound Authority will also contribute funds, although they in amounts as small as 10 parts per billion, the were not signatories to the CRADA. maximum permitted by the Occupational Safety and Health Administration (OSHA), in a large Packaging for thin-film batteries. Under a ; amount of SF6 (3) review gas-handling CRADA, ORNL and the Eveready Battery techniques and perform field sampling; (4) if Company of Westlake, Ohio, are developing a necessary, develop an absorbent or some other method for packaging rechargeable thin-fllm lithium batteries. These batteries, which are as way to remove S2F 10 from SF6 when the insulating

Number Two, 1992 161 TECHNOLOGY TRANSFER

small as shirt buttons and thinner than plastic positively charged electrode, or cathode. The wrap, must be sealed to protect them from air. second layer is the electrolyte, a new material Eveready has been developing a 2.5-V solid­ discovered by the group in 1991 and called state, thin-film rechargeable lithium battery, and lithium phosphorous oxynitride. The electrolyte recently ORNL developed its own rechargeable conducts lithium ions and separates the electrodes 3.7-V thin-film lithium battery. The ORNL and between which electrons flow in an external Eveready batteries have several potential circuit, providing needed electrical energy. The applications as miniature power supplies for third and top layer deposited is lithium, which microelectronics, including miniature sensors and forms the negatively charged electrode, or anode. "Eventually, micromotors. (For details on the ORNL The ORNL group will work with the Eveready development, see the article "Thin Films for Battery Company, which uses lithium for the thin-film Advanced Batteries" on p. 46 in this issue.) anode but different materials for the cathode and technology "Our goal is to develop a microbattery that electrolyte. The researchers will deposit protective could be fabricated directly onto a computer layers on test cells supplied by Eveready. The will make memory chip to preserve information in the event procedure will allow the battery to be sealed in possible the of a power failure," says John Bates, principal place on, for example, a carrier for a computer development investigator for the CRADA and leader of the memory chip. Ceramic Thin Films Group of ORNL's Solid "We will work with Eveready on determining of batteries State Division. "But before the thin-film battery is which thin-film material or combination of as small as ready for commercialization, we must develop a materials could best seal up the battery without protective thin-film coating." altering the properties of the films," Bates says. the period at Under a CRADA signed in March 1992 by He predicts the group will develop a self­ the end of Eveready and Martin Marietta Energy Systems, contained thin-film battery of more than 3.5 volts this Inc., the two organizations will develop a thin­ during 1992. "Eventually," he says, "thin-film film technique to seal the batteries and protect technology will make possible the development of sentence." them from exposure to air. Currently, the batteries batteries as small as the period at the end of this must be stored in a protective argon atmosphere sentence." to prevent corrosion of the lithium film. A successful packaging technology will make Computer images and geographic data for possible the rapid commercialization of the characterizing environmental conditions. ORNL and Eveready thin-film batteries. ORNL researchers are working under a CRADA Bates and his colleagues-Nancy Dudney, with staff from the Vitro Corporation of Silver Greg Gruzalski, and Chris Luck, researchers in Spring, Maryland, on the application of ORNL­ the Solid State Division-have been developing a developed computer software to the remediation rechargeable thin-film battery that could be of environmental problems. The CRADA partners fabricated directly onto a chip or its package. will use commercial systems and Geographic Currently, nonrechargeable batteries much larger Information Systems (GIS) software developed at than the chips are used to prevent loss of data ORNL to aid in site characterization and during power failures and must be added to remediation studies. The long-term goal is to circuits as separate components. A thin-film design, construct, and apply advanced GIS battery could be incorporated directly into the technology to support environmental assessment integrated circuit of a computer memory chip and restoration. during its manufacture. GIS software is a computer tool to aid in the To Wake its thin-film batteries, the ORNL management, analysis, and display of geographic group uses special equipment to deposit one layer and environmental data. Environmental of material at a time on a ceramic or glass surface, measurement data (e.g., concentrations of called a substrate. The first layer, made of groundwater contaminantsYare combined with noncrystalline vanadium oxide, forms the spatial information provided by maps of land

162 Oak Ridge National Laboratory REVIEW surface and subsurface features, aerial photography, and remotely sensed imagery to help assess the geographic extent, characteristics, and distribution of waste material. For example, a study of groundwater contaminant plumes, surface hydrology and drainage, and thermal imagery for seeps and springs may reveal potential pathways by which pollutants might migrate into nearby streams and "The long­ rivers. Results can be presented as two­ term goal is or three-dimensional displays to help to design, develop insights and remedy construct, environmental problems and to provide managers with decision and apply support tools to help justify and plan advanced remediation actions. The principal investigators for the CRADA at Richard Durfee uses Geographic Information Systems GIS software developed at ORNL to examine data on groundwater ORNL are Richard Durfee and Jerry contamination and movement to characterize subsurface technology Dobson, both of the Computing and conditions within hazardous waste areas. to support Telecommunications Division, in cooperation with the Environmental environmental Sciences Division. DOE funds in the partnership Oak Ridge Y -12 Plant will be used for sintering assessment are being provided by the Environmental the capacitors' tantalum anodes under various Restoration and Waste Management Program. conditions. The goal is to heat powdered tantalum and Vitro Corporation, which is owned by Penn to a rigid yet porous state. restoration." Central Corporation, provides software The expected results of the CRADA partnership engineering and systems integration support at are improvements in the quality and reliability of various military installations. The frrst phase of tantalum capacitors, which are desired by the A VX the GIS effort will focus on site characterization Tantalum Corporation, and a demonstration that for a Navy facility in Washington state. Later microwave sintering can have industrial phases will develop and test advanced GIS applications, which is important for the technology concepts in a network-based architecture. Such transfer efforts of ORNL and the Y -12 Plant. GIS technologies will be important in guiding the A VX Tantalum Corporation manufactures cleanup of hundreds of military sites, at a cost as tantalum capacitors by conventional vacuum high as $200 billion, by early in the next century. sintering. Microwave sintering is being tested to determine if it can surpass the conventional Microwave sintering of capacitors. ORNL technique by removing surface impurities from the and A VX Tantalum Corporation of Biddeford, tantalum particles, thereby improving the quality Maine, are collaborating under a CRApA in of the dielectric film, reducing cycle time, developing a method for manufacturing tantalum tightening process control, and increasing total capacitors--electrical components used in cardiac capacitance. pacemakers, electronic devices for the U.S. armed Research is under way at ORNL to identify and forces, and other applications requiring very high explain the physical changes in materials as they reliability. Microwave furnaces at ORNL and the are heated by microwaves. Observations of the

Number Two, 1992 163 TECHNOLOGY TRANSFER

A Foamseal technician constructs a polyurethane­ adhered roof assembly for thermal testing in ORNL's Large­ Scale Climate Simulator.

surface chemistry and morphology of processed effectively prevent heat from escaping houses in tantalum capacitors may give ORNL researchers winter and from entering them in summer. The fundamental insights into the actual mechanisms CRADA will help DOE's Building Thermal by which microwave sintering alters a material's Envelope Systems and Materials Program meet its properties. The principal investigator of the goals and increase industrial use of the Roof CRADA at ORNL is Robert Lauf of the Metals Research Center. and Ceramics Division. Two test ceiling panels were constructed by attaching dry wall to ceiling joists. One panel used Thermal performance of ceiling panels. mechanical fasteners, and the other used ORNL's Energy Division and the Urethane Foamseal's polyurethane adhesive for the Technology Division of Foamseal, Inc., are attachment. These two panels were tested at three working together under a CRADA to measure the different temperature conditions in the Large-Scale thermal performance of ceiling panels used in the Climate Simulator. construction of manufactured housing. The The heat flow measured on the panel using panels, which use a polyurethane adhesive urethane foam was about 10.5% lower than that manufactured by Foamseal, were tested in the measured on the panel using conventional Large-Scale Climate Simulator of the Roof mechanical fasteners. The measured thermal Research Center, a DOE user facility at ORNL. resistance of the panel using urethane foam was The goal of the CRADA is to help Foamseal 13.3± 0.4% higher than that measured on the panel improve its ceiling panels so that they more using mechanical fasteners.

164 Oak Ridge National Laboratory REVIEW "The foam adhesive offers an insulating benefit," to improve the design of condenser-absorbers for says Jeff Christian of the Energy Division, one of generating electricity using a Kalina power cycle. the principal investigators for the CRADA. The Kalina power cycles, which use working fluid other ORNL investigators are Ken Wilkes and Phil mixtures such as ammonia and water, will be Childs, both of the Energy Division. more efficient than conventional steam power systems and can be used with a variety of energy Thermal performance of roof insulation. sources, such as fossil, nuclear, solar, and ORNL's Energy Division, the Society of the geothermal energy. Plastics Industry, and the Polyisocyanurate "The Kalina power cycle system is like a Insulation Manufacturers Association are refrigerator working in reverse," says Fang Chen, collaborating under a CRADA. Their goal is to ORNL's principal investigator for the CRADA determine the thermal performance of experimental and a member of the Energy Division. "Instead foam insulation boardstock produced by U.S. of using electricity to make it work as a insulation manufacturers. refrigerator, the device uses a refrigerant for ORNL's Roof Research Center is being used to converting heat into electricity in the same way conduct thermal testing and determine the relative as water is used to make steam to drive a turbine. aging characteristics of ozone-safe roof insulation. The Kalina power cycle is more efficient than the The foam contains hydrochlorofluorocarbons steam power cycle because the working fluid (HCFCs), which do not persist nearly as long in the boils and condenses at a variable temperature stratosphere as chlorofluorocarbons (CFCs). whereas water in a steam cycle boils and One outcome of this work may be an improved condenses at a constant temperature." HCFC-blown roofing insulation that is nearly as ORNL researchers from the Energy and efficient in its thermal performance as CFC Engineering Technology divisions are insulation. As a result, it may be possible to conducting heat transfer tests of ammonia-water accelerate the elimination of CFC insulation for mixtures under various conditions of a Kalina roofs and help preserve the stratospheric ozone power cycle. They use condenser-absorber tubes layer that protects humans from hazardous solar supplied by Exergy for the condensing heat radiation. transfer tests. A second major outcome is the development of a The researchers will determine the effects of procedure to accelerate the thermal aging process ammonia-water film condensation at various of these foams so that the long-term resistance to thicknesses on the heat transfer of tube surfaces heat flow (R value) of these HFC-blown closed-cell under various conditions of the Kalina power foam insulations can be predicted. These foams cycle. The results of the tests will be used to lose some of their thermal resistance as a result of develop an engineering design data base to the diffusion of air into the foam and the diffusion improve the design and development of cost­ of the blowing agent out of the foam. An accurate effective condenser-absorbers for Kalina power estimation of the lifetime R-value of these foam cycle systems. This project is a part ofthe insulations will provide a benchmark for Thermal Sciences Program of DOE's Office of developing even better insulations. Industrial Technologies. The principal investigators from ORNL for this CRADA are Ron Graves of the Metals and Development ofradiation detector. ORNL Ceramics Division and Jeff Christian, George and Pellissippi International, Inc. (PI), of Courville, and Randy Linkous, all of the Energy Knoxville have signed a CRADA to develop a Division. new type of radiation detector. ORNL scientists will conduct research and Heat transfer studies of Kalina power cycle design studies for a dosimeter that, for the first systems. ORNL and Exergy, Inc., of Hayward, time, could detect neutrons through optical California, are working together under a CRADA imaging of charged-particle tracks in a gas. As

Number Two, 1992 165 TECHNOLOGY TRANSFER

part of an anticipated two-year joint effort, PI will machining, developed from manufacturing develop a prototype optical detector chamber to components for nuclear weapons, and ORNL's which ORNL will have access for research. expertise in advanced materials. These Neutron measurements are required for capabilities are being combined in the recently personnel protection at facilities where this established Ceramic Manufacturability Center "ORNL radiation occurs. An improved radiation detector jointly funded by DOE's Conservation and scientists employing this latest technique could monitor Renewable Energy and Defense Programs neutron radiation levels more accurately and offices. will conduct provide additional information beyond existing "This collaboration in the field of precision research and capabilities. If successful, the new cooperative machining of ceramics parts is in the middle of research also could open new avenues of research one of our fields of expertise," Carpenter said. design in radiation physics. "That a large manufacturer of diesel engines is studies for a James E. Turner and Robert N. Harnm, both of willing to collaborate with us in this field is a dosimeter ORNL's Health and Safety Research Division, testament of great value to us. We intend to use developed the optical detector in collaboration our expertise to assist Detroit Diesel in its that, for the with former staff members Scott R. Hunter, G. commercial quests. We both can benefit greatly." first time, Samuel Hurst, and Harvel A. Wright. For the idea, Objectives of the project include improving the group was awarded a patent, which has been the accuracy and consistency of critical could detect assigned to PI. The work there is being coordinated dimensions on ceramic components such as neutrons by Hunter and PI's president, William A. Gibson. diesel engine fire decks, cam roller followers, through The research is being sponsored by DOE's engine valves, injector components, and other Office of Health and Environmental Research and similar parts. Manufacturability issues will be optical the National Cancer Institute. addressed using techniques such as component imaging of thermal analysis, finite element modeling, and CRADA with Detroit fluid flow analysis. charged­ The project will support DOE's Defense particle Diesel on Ceramic Programs and Conservation and Renewable tracks in a Energy technical needs in manufacturing hard Engine Parts materials and will enable U.S. industry to gas." maintain a position of leadership in the structural Energy Systems and Detroit Diesel Corporation ceramics field. have signed a CRADA for developing advanced Under this three-year agreement, costs of the technology and manufacturing practices to cooperative research effort will be equally shared machine and inspect ceramic components used in by Detroit Diesel Corporation and DOE (through heavy-duty diesel engines. Detroit Diesel has Martin Marietta Energy Systems) at a total cost become a leading manufacturer of such engines of $2.4 million. and has been responsible for such innovations as Operations will be conducted in a Ceramic the electronically-timed unit fuel injector. Manufacturability Center now being established The CRADA was signed in Detroit Diesel at ORNL's High Temperature Materials Corporation's headquarters by Roger Penske, Laboratory (HTML) under a cooperative chairman and chief executive officer of Detroit program for Precision Machining of Cost­ Diesel, and William W. Carpenter, Energy Effective Ceramics Components. Location of the Systems vice president for Technology Transfer. center in the HTML enables Detroit Diesel The signing was witnessed by Richard A. Claytor, Corporation and other industrial participants in Assistant Secretary for Defense Programs, U.S. the program to take advantage of the world-class Department of Energy. materials capabilities available at the HTML. The research effort will rely on the expertise of Ceramics are an attractive material for use in DOE's Oak Ridge Y-12 Plant in precision engines. They are stronger and lighter than steel

166 Oak Ridge National Laboratory REVIEW and can tolerate much higher temperatures. Because engines are more efficient when operated at higher temperatures, ceramics have long been envisioned for use in advanced engines. Materials research funded by DOE has led to the development of several promising ceramics compounds for industrial applications, but the Carl Burtis shows development of machining and quality inspection the Abaxis techniques necessary to mass produce cost­ disposable rotor effective ceramics has not kept pace with the that will be used to development of the materials. monitor patient The lack of precision machining is considered health. to be a principal barrier to the use of ceramics in engines. Precision machining technologies for ceramics and other hard materials have been developed at the Y-12 Plant as part of manufacturing nuclear weapons components. ORNL's Blood Rotor Licensed to Abaxis A new medical device, about the size of a small toaster, that can analyze a single drop of blood will be available next year to help physicians Abaxis plans initially to produce different types assess the health of their patients. This is the hope of rotors, each of which will be designed to of Abaxis Corporation of Mount View, California, monitor a specific health function. For example, which is completing the development of this some of the first rotors available will be used for product based on an ORNL technology. Abaxis general health monitoring, and others will be will be marketing the medical analyzer throughout used to assess the health status of specific organs the world in 1993 under a recent licensing such as the liver or heart. agreement with Energy Systems. The new device will analyze blood for The Abaxis device is a miniaturized and cholesterol, glucose, total protein, and other computerized version of a centrifugal analyzer, an chemicals that indicate whether a patient's heart, instrument invented in 1967 at ORNL by Norman liver, kidneys, and metabolism are functioning Anderson and his associates. The unique feature properly. For example, elevated levels of certain of the Abaxis analyzer is a sophisticated proteins called enzymes can indicate organ disposable rotor, a clear plastic disk that fits in the malfunction. palm of your hand. It is based on a rotor To begin an analysis, a technician first developed by Carl Burtis of ORNL's Chemical removes a rotor from its foil package and Technology Division and two retired employees­ introduces a drop of a patient's blood onto the Wayne Johnson, formerly of the Instrumentation rotor's loading port. Capillary tubes in the rotor and Controls Division, and Bill Walker, formerly draw the blood into a central mixing chamber of the Plant and Equipment Division. where it is diluted. The rotor is then placed into Each rotor in the analyzer contains the chemical the analyzer and alternately spun and stopped to agents and processing chambers needed to remove blood cells from the plasma in the automatically process and analyze a single drop of sample. The plasma, which contains the whole blood for substances of medical interest. chemicals of interest, is radially moved from the

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central chamber to the rotor periphery, where DOE Labs and portions of it are mixed with reagents present in the individual reaction chambers. Utilities Interact The reagents react with specific components of the blood to form chemical compounds. The rates ORNL is one of several DOE laboratories "The unique of individual chemical reactions and the involved in the Optical Sensing Manufacturers/ feature of the concentrations of the newly formed light­ Utilities Group (OPSM/UG), an organization formed in 1991 to match the needs of electric Abaxis absorbing compounds can be determined by passing light into the chambers and measuring the utilities with technology for new optical sensing analyzer is a emerging light signals. Light signals are applications. The group also encourages its sophisticated transmitted and measured by a stationary optical members to jointly develop, test, and demonstrate system within the analyzer. new technologies. disposable The amount of light transmitted through a For the utilities, sensors using advanced optical rotor, a clear chamber indicates the level of a particular body detection technologies will play a key role in plastic disk chemical in the blood. Variation in light intensity addressing increasingly complex issues in over time indicates reaction rate and, thus, the environmental monitoring, power generation, that fits in levels of other chemicals. power distribution, and load control. the palm of The system's software converts the measured Eric Wachter, a research staff member in light-transmission signals into units of ORNL's Health and Safety Research Division, your hand." concentration or activity (reaction rates) and said DOE will benefit from its involvement. prints or stores this information, which is later "Much of the technology that DOE is committed uploaded to a larger computer. From this to develop, such as that needed for environmental information, physicians can diagnose disease and monitoring, can be used by private industry," organ malfunction or pronounce the patient to be Wachter said. "By working with utilities and in good health. optical sensing manufacturers, we will be able to develop joint approaches to sensing applications." OPSM/UG's fLrst meeting, held April 15, 1992, was hosted by Southern California Edison at its research center in Irwindale, California, and was timed to coincide with the Expo Sensors West exposition in nearby Anaheim. 11!:!1

168 Oak Ridge National Laboratory REVIEW

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