Oak Ridge National Laboratory ~ w~rvo~ Oak Ridge National Laboratory W~[VO~W VOLUME 15 NUMBER 4 FALL 1982

2 Silver Recovery from ORNL Wastes By CAROLYN KRAUSE

THE COVER: Electrochemists Franz Posey (front) and Al Palko have developed highly efficient methods of rewvering silver from ORNL's photographic and photowpier waste 9 UNISOR: The First Decade liquids. See the article on page two. By RUSS MANNING

Editor BARBARA LYON 18 Minerals in the Wilderness Staff Writer How Important Are They? CAROLYN KRAUSE By JON JEFFERSON Consulting Editor ALEX ZUCKER Design BILL CLARK Departments Editorial 1 Take a Number 8 Books: 15 Polywater Resaurces and Development Publication Staff: Technical Editing/Lydia Readers Comments 17 Corrill, Ralph Sharpe, Jenny Vinson; Ty­ Information Meeting Highlights 24 pography/Composition Unit; Makeup/Betty Flywheel Evaluation Jo Williams; ORNL Photography and Repro­ Coal vs Nuclear Costs duction Departments. Tokarrw,ks: Results and Plans ELMO Bumw Torus: An Update Mechanisms of Metal Fracture Laser Annealing and Melting The Review is pu bli shed quarterly and dis­ Superconductivity and Magnetism tributed to employees and others associated Awards and Appointments 28 with the Oak Ridge National Laboratory. The editorial office is in Bui lding 4500-North, Oak Ridge National Laboratory. P.O. Box X, Oak Ridge, Ten nessee 37830. Telephone: Internal 4-7183; commercial (615) 574-7183; FTS 624 -7183. OAK RIDGE NATIONAL LABORATORY ISSN 0048-1262 OPERATED BY UNION CARBIDE CORPORATION · FOR THE DEPARTMENT OF ENERGY EDITORIAL

A Valedictory

This issue of the Review is the last one that will have my name on the masthead. By the end of September this year, I will have shifted gears, so to speak, and be launching into a new life-style. To have been associated with both this magazine and the Laboratory which it celebrates for 15 years has been a singular treat. The Review has come into a number of blessings in that time, a few of which are significant enough to mention here. Not the smal­ lest of these blessings was the magazine's inception at the hands of Dave Sundberg. Dave, who had earlier designed and started The Atom at Los Alamos, was brought here from the editorship of Nuclear News in 1966 by Alvin Weinberg. Dave's assignment was to design an ORNL journal along the lines of the CERN Courier, published by the Conseil Europeenne pour la Recherche Nucleaire in Geneva. The extent to which the ORNL Review never entirely measured up to those standards rests squarely on my shoulders, because Dave almost immediately moved on to directorship of the Office of Public Information and I then inherited the ORNL Review, which I have not relinquished till now. In 1973, when the Laboratory underwent the gravest reversals in its history, Acting Director Floyd Culler personally saved the Review from falling as did many of the larger, crumbling programs. In 1975, shortly after taking office, the new director, Herman Postma, instructed the Review to supplant the Laboratory's annual report, an honor which we have since tried to live up to by offering in any four-issue series a broad cross section of Laboratory pro­ grams and research for the year covered. In that same year, Director Postma also gave his imprimatur to the acquisition for the Review staff of the leading science journalist in the area-Carolyn Krause. Carolyn, who, with Jon Jefferson, will take over the magazine from me, can claim principal responsibility for the international prizes that the magazine has since received. Not the least of the blessings was the assigning, back in 1967, of artist Bill Clark to sole responsibility for the design of the publication. I am lucky to have had a chance to work with someone of his talents and discerning eye, and, with every issue, I have learned from him. He, too, has garnered many prizes for the Review. Because no Laboratory director can afford the time to monitor the contents of the magazine's every issue, a mentor was assigned from the beginning to represent Laboratory management. First to critique and support the selection of manuscripts was Art Snell, who since has retired but who is, happily, in occasional residence. He guided with a light hand and infrequent mild demurral-an early supervision for which I will always be grateful. At his departure, we were again fortunate in the assignment as his replacement of Alex Zucker, a man of equally high scientific and literary standards. He has served as the magazine's severest critic and staunchest protector and will continue to ensure its high quality, as will the others remaining on the staff. So, this slight alteration in the masthead marks no great change. The magazine will prevail. The loss is only mine.- B. L.

FALL 1982 1 J. R. Junes inspects a Hazardous Waste sticker an one of the 176 210-L (55-gal} drums in which photocopier waste liquids containing silver are stored. It is hoped that up to 23,000 L (6000 gal) of this effluent wiU be run through the pilot plant to recover its silver.

Tom Oakes shows a silver ingot recently made of recovered silver from photocopier waste.

Silver Recovery from ORNL wastes

By CAROLYN KRAUSE ~ here is a silver lining to the ing a higher percentage of the processes, their primary motivation lJ. cloudy liquid wastes generated silver content has been kindled was to remove a potential environ­ by ORNL's photographic and photo­ recently because of new environ­ mental hazard; to recover wealth copying equipment. Nearly 107,000 mental regulations forbidding from waste was secondary. L (30,000 gal) of waste liquids pro­ discharges of high concentrations of The wastes generated by ORNL's duced each year at ORNL contain toxic metals. Photography and Reproduction silver, which had a market value of ORNL chemists have now departments contain silver ions in $10 per troy ounce in 1981 and as developed two processes for highly concentrations ranging from about high as $40 in 1979. The precious efficient recovery of silver from 0.5 to 20,000 mg/L. These wastes metal has been recovered electrolyt­ Laboratory wastes. Unlike hun­ must be treated before they can be ically from ORNL waste liquids dreds of other researchers who legally discharged to the environ­ since 1968, but interest in recover- have developed silver-recovery ment or to secondary sewage-

2 OAK RIDGE NATIONAL LABORATORY Review Gary Westmoreland inspects the silver ingot treatment facilities. Tennessee law toxic. Silver ions can destroy the 11UUle lYy meUing dcnun silver extracted from specifies that the acceptable bacteria used at secondary sewage­ ORNL wastes. On the left is a jar of cloudy photocopier solution that awaits treatment in discharge level to the environment treatment plants to treat liquid the pilot plant behind him. At right is a jar of for silver ions is 0.05 mg/L. wastes. treated waste clean erwugh to meet legal lim­ The state law is so stiff that elec­ Because ORNL's photocopier, or its for discharge into the environment. trolytic silver-recovery processes photoreproduction, wastes contain developed by private industry high concentrations of silver, they (including Eastman Kodak Com­ have been stored in 208-L (55-gal), pany in Rochester, New York) can­ plastic-lined metal drums and plas­ not meet Tennessee's environmental tic carboys. Now, however, these standards for photographic wastes are being treated in a pilot effluents, even though the best elec­ plant in ORNL's Chemistry Divi­ trolytic processes can recover 98% sion. The pilot plant promises to of the silver. ORNL's new processes, save money in the long run because however, which are 99.99% (1) the cost of chemicals used may efficient, can yield liquid wastes be less than the current market clean enough to dump down the value of the silver recovered and (2) drain. ORNL will no longer have to spend There is a good reason for an estimated $40,000 per year for Tennessee's stringent law: besides disposal expenses, plus container being a precious metal, silver is costs and shiJ!ment fees.

FALL 1982 3 Sharon Robifl80n checks the temperature of the 110-L (S(}.gal) reaction 1Je88el used for testing the hypochlqrite-hydrazin£ proce88 of recovering Bilver.

Gary Westmoreland preparea to install afilJ,er The pilot plant uses sodium Franz POBel/ ruJ,jugts the vent tube at the tup in the croB8-f/,ow filtration 81JBtem used to of the 760-L (f()().gal) stainless Bteelve88el t dithionite in a new silver-recovery filJ,er out Bilver in hardr~treat wastes .ftwn which i8 part of the Bilver recovery pilot plant process developed by Franz Posey the storage area Mar Building 7()()(). Looking in Josh Johfl80n:, laboratory in the Chemi8try and AI Palko of the Chemistry on i8 Mike Eisenlwwer. Division. Division. (Palko is now retired.) found that the content of the cost of disposing of a huge volume Both men are electrochemists who effluent sample exceeded the of liquid wastes, which contain col­ developed various electrolytic maximum level permitted by the loidal silver from developer rinses methods for removing toxic metals EPA, Oakes banned the release of and high concentrations of dis­ from waste streams in the 1970s for photoreproduction wastes to solved silver in fixer solutions. the National Science Foundation's streams and ordered that these In early 1980, Brian Kelly from Environmental Program at ORNL. wastes be held in drums and Oakes' group was discussing the Ironically, they found they had to carboys for subsequent shipment to photographic waste problem with abandon the electrolytic approach a landfill or other approved dispo­ electrochemist Al Palko, an ama­ and turn to traditional chemistry to sal site. teur photographer who develops find a practical, cost-effective, and Photographic wastes are less of a film in his darkroom at home. Dur­ highly efficient process for silver problem. Since 1978 the ing the conversation, Palko pointed recovery. Photography Department has out that he and Posey had tried Trial and Error recovered silver electrolytically electrolytic methods of cleansing from fixing solutions used to waste streams of silver, mercury, The story of how ORNL research­ develop black and white photo­ lead, and other toxic metals as part ers became involved in extracting graphs, papers, and films, including of the Environmental Program. silver from wastes began in 1979 x-ray films. The department Kelly encouraged Palko and Posey when ORNL's environmental coor­ employs a metallic replacement to try developing a highly efficient dinator, Tom Oakes, became con­ method to recover silver from electrolytic separation scheme for cerned that the Laboratory's bleach-fix solutions used in develop­ silver-bearing wastes. effluents were violating Tennessee ing color photographs. Abandoning their corrosion stu­ and the Environmental Protection Meanwhile, Oakes and Stewart dies temporarily, Posey and Palko Agency's limits for silver. Oakes discussed the need for ORNL to set out to test a silver separation asked Joe Stewart and Marion Fer­ develop an efficient treatment pro­ scheme that they thought would guson of the Analytical Chemistry cess for silver-bearing photorepro­ work well. Using porous graphite Division to analyze photoreproduc­ duction wastes to meet environmen­ electrodes, they ran a process that tion wastes for silver. When they tal constraints and save ORNL the recovered most of the silver but

4 OAK RIDGE NATIONAL LABORATORY Review was impractical because it re­ lysis only to find that the process light, a fixer is used to remove the released the silver ions within a had two limitations. First, the large amount of unreacted silver short time. silver thiosulfate complex at the halide so that it will not react electrode surface reacted with further with light. Typically, more More Silver Through Chemistry adsorbed hydrogen (an intermediate than two-thirds of the silver in the in a side reaction) to form silver emulsion comes out in the effluent, Searching the literature, Posey sulfide, which plugged the pores of which contains 5 to 6.5 giL of and Stewart discovered approxi­ the graphite electrodes; because the silver. mately 10,000 papers, articles, and electrodes became plugged quickly, Posey and Palko decided to patent disclosures that relate to they were no longer useful for experiment with the electrolytic silver-recovery procedures. Those removing silver from effluents. solution to search for chemical which appeared to be efficient Second, the silver sulfide sludge reactions that prevent the forma­ enough to meet today's environmen­ was itself a disposal problem. Of tion of silver sulfide. They investi­ tal limits for wastewater discharges course, silver could be recovered gated methods of decomplexing the presented other problems, such as from this sludge, but only by using silver or converting the thiosulfate formation of colloidal precipitates an expensive process. to another chemical form. They or sludges that are difficult to filter The source of the silver sulfide used electrochemical techniques to and may pose an additional problem is the thiosulfate follow reactions in the photographic disposal problem. fixer-usually sodium thiosulfate or solutions involving oxidation In their reading, they found that ammonium thiosulfate-used to (removing electrons) and reduction many silver-recovery processes use make a photographic image per­ (donating electrons). electrolysis, which normally manent. Although a developer is At one point, Posey suggested removes 80 to 90% of the silver, not used to convert to silver metal the that they use sodium hypochlorite enough to meet EPA standards. tiny amount of the film's silver to get rid of the thiosulfate. He had Posey and Palko had tried electro- halide that has been activated by read that hypochlorite had been

FALL 1982 5 used in other silver-recovery solution, which then coagulated into analytical services and continuing processes for removing the thiosul­ an easily filterable precipitate of encouragement provided by Joe fate. His idea, however, was to oxi­ pure silver metal. The principle of Stewart and his colleagues." dize the thiosulfate by drawing the constructive bumbling works. Some­ A Better Technique photographic solution into a reser­ times it's better to be lucky than voir of hypochlorite rather than by smart." In late 1981, when environmental the commonly used reverse method Posey and Palko tried the new managers at ORNL became con­ of adding the hypochlorite to the process on spent fixer from ORNL's cerned about the possibility of silver effluent. By adding the fixer Photography Department. They ran Laboratory pilot-plant operators to the hypochlorite, he was able to the fixer into a reservoir of hypo­ being exposed to the toxic chemical maintain oxidizing conditions; this chlorite and allowed the silver hydrazine, Posey decided to try ensured that the silver liberated by chloride precipitate to remain in another chemical mentioned in the oxidation of the thiosulfate reacted the pot for a day "to let Doctor literature which has the advantages with chloride (reduction product of Time work on it," as Posey puts it. of being safer than hydrazine and hypochlorite) to precipitate silver Then they added hydrazine and cheaper than hypochlorite. The chloride, rather than the silver sul­ watched as the strong reducing chemical, a powerful reducing agent fide that precipitates under reduc­ agent converted the silver chloride used by the textile industry, is ing conditions. The reaction was to pure silver. Analysis by Stewart sodium dithionite; it had been tried followed by monitoring the showed that hypochlorite-hydrazine by others before in silver-recovery oxidation-reduction potential of an treatment of the effluent signifi­ processes but always produced what inert electrode in solution. cantly reduced its silver content, Posey did not want-silver sulfide. "In most processes," says biological oxygen demand, and Posey thought that, if the chemi­ Stewart, "the silver-bearing chemical oxygen demand. Once the cal were used under the right con­ material is treated with hypochlor­ silver was filtered out, the ditions, it might recover nearly all ite, which turns the material into a remaining solution was clean of the silver without making silver black colloidal precipitate of silver enough to pour down the drain. The sulfide. Sure enough, he found that sulfide, which is very difficult to recovered silver, according to his goal could be achieved by prop­ filter. What Posey did was to Stewart's x-ray fluorescence erly controlling pH, adding reverse the process and run the analysis, was 99.9% pure, with just reagents slowly, and using an argon fixer solution into the hypochlorite a trace of iron, magnesium, and or nitrogen blanket to prevent the and add a few drops of a 'magic bromine. sodium dithionite from reacting ingredient' to get the silver out in Palko then attacked the problem with oxygen from the atmosphere. the form of a greyish spongy mass of recovering silver from the Subsequently, Posey and Palko of agglomerated silver particles developer and developer rinse used showed that sodium dithionite can that can be filtered easily." in the Reproduction Department. also act in the same manner as Silver in photoreproduction hydrazine for precipitation of silver "Constructive Bumbling" developer eludes recovery because it from developer and developer rinse. is predominantly in the form of a This new process allows very effi­ The magic ingredient was hydra­ colloid-a suspension of finely cient recovery of silver without the zine, a powerful reducing compound divided particles that tend not to toxicity hazard associated with the of hydrogen and nitrogen used, in settle out of solution and resist use of hydrazine. Earlier this year the anhydrous state, as a fuel in being filtered. Palko found he could they developed a thionite process the United States space shuttle. precipitate the silver in filterable for silver recovery from spent x-ray Posey came upon hydrazine while form by using hydrazine. Hydra­ fixer. This modified process over­ experimenting with a number of zine apparently causes the silver came the problem of the high alum reducing agents, doing what he ions to come out of solution and content of x-ray fixer; alum inter­ calls "slopjar chemistry." When he serve as nuclei for the agglomera­ feres with the process used for tried diluted hydrazine on a fixer tion of the colloidal silver, which silver recovery from photographic solution that had been treated with resembles black cottage cheese. fixer. Finally, they developed a hypochlorite, it worked beautifully. "The successful development of process for treatment of a mixed Says Posey: "We found that only a these silver-recovery processes," photoreproduction effluent contain­ few drops of hydrazine were suffi­ says Posey, "would have been diffi­ ing the developer, developer rinse, cient to form a silver colloid in cult without the coordination of activator, and activator rinse.

6 OAK RIDGE NATIONAL LABORATORY Review processes. Consisting of a 760-L Recovery of Precloua lletllle (200-gal) vat and cross-flow filtra­ tion equipment to filter out silver Recovery of precious metals such as silver, gold, platinum, and iridium from the liquid wastes, the pilot has been performed at ORNL for 15 years. By recovering these metals from plant is conveniently located in wastes and either selling or recycling them for further use, ORNL saved Building 4500S, where photorepro­ $1,804,409 in 1981 alone, according to Bill Graves, head of the Materials duction wastes are generated, thus Department in the Finance and Materials Division. Most of the savings saving labor and money in getting (slightly more than $1 million) resulted from recovery of iridium. the wastes to the silver-recovery As for silver, ORNL saved $16,635 in 1981 by selling scrap x-ray film, plant. silver-bearing scrap, and discarded hypo solution used in processing x-ray, Preliminary results indicate that black-and-white, and color film. Silver was recovered from solution by all but 0.2 to 0.5 mg/L (0.5 ppm) of electrolytic, metallic displacement equipment located in ORNL's Photography silver can be recovered from pho­ Department. Discarded hypo solutions are collected from 13 locations in the toreproduction wastes in the new Laboratory and delivered to the processing system. Arrangements for the pilot plant. Discharge into the sani­ transfer are made by Bill Longaker, field engineer in ORNL's Plant and tary sewer system dilutes the Equipment Division. remaining silver concentration well Other film wastes are collected in silver-recovery cartridges, which are below EPA and Tennessee limits. delivered to the Materials Department for sale on a bid contract arranged by "This meets EPA and Tennessee's the Purchasing Division. limits for allowable silver in Now that ORNL has a new silver-recovery process that is being tested in discharges of wastewater," says a pilot plant, there is hope that even more silver can be recovered for sale, Mike Eisenhower of Oakes' environ­ not only from photographic film wastes, but also from 23,000 L (6000 gal) of mental management group. photocopier wastes currently being stored in drums. Eisenhower has the responsibility of seeing that ORNL's treated discharges of silver-bearing wastes do not exceed environmental limits. Posey and Palko's new silver­ Chemical Technology Division to For each 570-L (150-gal) batch of recovery "recipe" for mixed pho­ test these processes for ORNL photoreproduction waste run toreproduction effluent addresses effluents on an engineering scale through the pilot plant, about 400 g the problem of the effluent's aci­ and to evaluate the economics of of silver is recovered. Silver was dity. "Sodium dithionite will not treating ORNL waste, both the worth only about $7 per troy ounce work properly in neutral or acidic backlog and that currently gen­ this past summer, but this value solutions," Posey says, "so we had erated. A small plant for treating constantly changes and is likely to to raise the pH and make the solu­ 95-L (25-gal) batches, using the rise in the near future. Use of the tion basic." This was accomplished hypochlorite-hydrazine and sodium new silver recovery process will by adding water and ammonium dithionite processes, was assembled save ORNL approximately $80,000 hydroxide (ammonia) to the in January. The plant, operated by in disposal and shipping costs. At effluent to attain the proper dilu­ Sharon Robinson, demonstrates the current values, recovered silver tion and pH. Ammonia also helps feasibility of scaling up the process. could be worth up to $25,000 annually. achieve agglomeration of the silver. A subsequent engineering study ORNL has been concerned with After bubbling argon through the determined that it would not be the value of silver since the late solution to protect sodium dithion­ economically feasible to process 1960s when the precious metal ite from exposure to atmospheric batches on a small scale and that recovery program began and when oxygen, Posey added the sodium existing equipment could be used the last 67 of 14,700 tons of silver dithionite and heated and stirred for process scaleup. once used in the electromagnetic the mixture. All the silver was A decision was made to assemble isotope separators was returned to removed in pure form. a full-scale pilot plant using exist­ the U.S. Treasury Department. ing equipment in one of the labora­ Now, however, the value of silver is Pilot Plant tories of Josh Johnson in the Chem­ of interest because it not only saves istry Division. The pilot plant, ORNL money but also may permit Enthusiastic about the processes operated by technician Gary West­ ORNL to solve an environmental developed by Posey and Palko, moreland, is now being used and legal problem in a cost­ Stewart and Oakes asked the exclusively to test sodium dithionite effective way. a

FALL 1982 7 7

ea mber

By V. R. R. Uppuluri

When a standard cubic die is rolled dice: None of the totals that may or equal to 10. The probability of once, either one, two, three, four, appear on the top faces in a single this event is 1/2. five, or six dots appear on the top roll can be neglected, and the two face. When the die is not loaded, players have an equal number of In general (unless we add complex­ each of these six events occurs choices. It is interesting to note ity to the rules), when we roll an with probability 1 I 6. that, under these rules, no such fair even number of dice once, no fair game between players A and B is game with even chances between One can make a fair game between possible when two dice are rolled two players is possible; whereas two players A and B, where, in a once and the total number of dots when we roll an odd number of dice single roll, player A wins if the on the top faces determines the once, such a game is possible. number of dots appearing on the winner. top face of the die is either 1, 2, or 3 and player B wins if 4, 5, or 6 Once again, when three dice are In a plane, let A, B, and C denote dots appear. Thus, with one die and rolled once and the total number of the three vertices of a triangle and one roll one can have a fair game in dots on the top faces determines let a denote side BC, b denote side which the chance of either player the winner, a fair game (50:50 CA, and c denote side AB. If angle winning is 50:50. odds) between players A and B is B is twice angle A, then b2 = a2 possible. More specifically, player A + Let us generalize the conditions ~c . The converse of this statement can opt to win if the total number of used for a single die into rules for a is also true: if b2 = a2 + ac, then dots on the three faces is less than simple game with any number of B = 2A.

8 OAK RIDGE NATIONAL LABORATORY Review Ran Mlekodaj of the UNISOR Btciff lowers the focal plane, whick has slits fqr selecting 11Ul88-separated bea17!8 fqr study.

UNI~OR: The First Decade By RUSS MANNING

[\I\ ost of what physicists know about the structure Several rather successful nuclear structure models, Ll\7}1and behavior of the atomic nucleus has come such as the shell model and the collective model, were from experimental work with stable or nearly stable partially based on this strong correlation between pro­ nuclei. These stable nuclei exhibit characteristic neu­ ton and neutron numbers of the stable nuclei. To further tron-proton configurations, or ratios, which make them test the validity of these models, many physicists stable, placing them in what is called the "valley of sta­ believed it necessary to study nuclei with proton and bility." neutron numbers different from the stable and near­ stable nuclei (i.e., unstable, or short-lived, nuclei). Russ Manning is a former ORNL employee who left the That was the purpose of establishing the University Chemical Tech7wlogy Division in 1976 to pursue a writing Isotope Separator at Oak Ridge in 1971, an isotope career. Since then his articles on science, travel, and the separator on-line to the Oak Ridge Isochronous Cyclo­ crutdoors have appeared in numerous periodicals across tron at ORNL. The higher energies and heavy-ion beams the ccruntry. His writing has won awards frmn the East available at ORIC made it possible to produce nuclear Tennessee Chapter of the Society for Technical Cmnmuni­ reactions yielding isotopes far from stability, those with cation and the Tennessee Outdoor Writers Association. He half-lives of less than 100 seconds. is currently a science writer and editor for ORA U An isotope separator was needed, explains Gene Photographs for this article were taken by ORA U photo­ Spejewski, director of UNISOR, "because all the pro­ grapher John M Richards, Jr. cesses we know about for making unstable isotopes pro-

FALL 1982 9 duce not just the specific nuclide for study, but a whole family of nuclides. To do any kind of reasonable experi­ ment, we had to make a separation of some kind." UNISOR was formed as a user group to involve researchers from various institutions. Several universi­ ties joined the project, and the State of Tennessee pro­ vided funds for the separator. Oak Ridge Associated Universities agreed to act as the fiscal agent, and so UNISOR became a division of ORAU. Over the years, DOE has supplied most of the funds for operating expenses. Ten universities renewed their UNISOR participa­ tion in 1981. Investigators from these and other research institutions are supported by the UNISOR staff, which is responsible for development and mainte­ nance. Ron Mlekodaj and Ken Carter have worked with Spejewski since the early years; Georg Leander recently joined the staff as a theoretician. An executive committee made up of one representa­ tive from each member institution oversees UNISOR. The committee currently is headed by Lee Reidinger, acting chairman of the Physics Department of The University of Tennessee, Knoxville. Once a research beta decay to more stable configurations of protons and proposal is accepted by the program advisory committee neutrons, which places them back in the valley of stabil­ of the ORNL Holifield Heavy Ion Research Facility, all ity.) It was first necessary to get the product nuclei into UNISOR member institutions are invited to participate an ion source. in the approved experiment. Because of the large linear momentum of the heavy Facility Development ions, the product nuclei recoil out of the target and are trapped in a catcher, usually graphite felt mounted in A formidable task during the first ten years of the wall of an ion source. To get the product nuclei UNISOR has been the development of the facility, con­ to diffuse out of the graphite and into the source, the necting all the major components-the accelerator, the UNISOR staff designed the ion sources to reach high isotope separator, the collection and measurement temperatures of 1000-1800°C. Current development of devices-and developing the capability to produce and sophisticated ion sources that can attain higher tem­ study nuclei that appear interesting. peratures of 2500-3000°C makes it possible to study "Physicists have known for a long time how to more isotopes, especially the difficult lead, bismuth, and make unstable nuclei," says Spejewski, "and we've gold isotopes and the rare earths. known how to make mass separations. But with most Once the product nuclei have vaporized into the ion such projects, the problems are in the interfaces, in con­ source, they are ionized (usually by an electrical necting the pieces together." discharge), extracted by means of an electric field, and To produce nuclei far from stability, a target accelerated down a second beam tube to the isotope material is bombarded by a heavy-ion beam which trav­ separator. els down an evacuated tube from the isochronous cyclo­ An alternative method is a recently developed tron at energies of 50 to 200 MeV. The heavy ions avail­ helium-gas jet system in which the product nuclei are able from ORIC include those of carbon, nitrogen, oxy­ stopped in the helium and pumped into an ion source, gen, and neon. With the recent addition of the 25-MV eliminating the need for a catcher. This new project is tandem accelerator at HHIRF, beams of higher energy coordinated by Dennis Moltz of the ORNL Physics Divi­ and higher mass are now possible. sion, with pieces of the system constructed by several The product nuclei that result from the collision of member universities. Although not as efficient as the the heavy ions with the target are highly excited and standard technique, it eliminates the time necessary for spew out neutrons to make unstable neutron-deficient vaporization, an important factor when studying iso­ nuclei. An initial interface problem was how to get these topes that are very unstable and thus very short-lived. product nuclei from the target to the isotope separator Once in the isotope separator, the product nuclei are before decay is complete. (The nuclei eventually undergo electromagnetically separated according to mass. Defin-

10 OAK RIDGE NATIONAL LABORATORY Reyiew intrinsic angular momentum of the nuclei. Emitted gamma rays will form a pattern as a function of angle around the aligned direction of nuclear spin, which will allow the researchers to deduce the spins and parities of nuclei. A fourth mass-separated beam line is directed to a newly installed laser optical spectroscopy system which can be used to precisely determine the hyperfine struc­ ture of atomic levels that result from the interaction of the nucleus with the atomic electrons. These measure­ ments enable the researchers to independently measure certain ground-state properties, in particular the ground-state spins of odd-mass nuclei. The new laser system contains a dye laser in which the molecules of an organic dye absorb the light of an argon pump laser and become excited. In making the transition down to the ground state, the molecules emit light in a continuum. The dye laser can then be tuned to pick out a particular frequency, which is used to excite the hyperfine structure in the atoms or ions. Ken Carter of the UNISOR staff and Carrol Bing­ ham of UT have done much of the work with the laser system. "While the fundamental principles of hyperfine Dennis Moltz adjusts the new heliu:m·ga8 jet system, which when cou­ structure and isotopic shifts have been known for more pled to an ion saurce, wiU eliminate the need for a graphite catcher and, thus, the time necessary for vaporization. Moltz wmpleted post-doctoral than 40 years," says Carter, "the use of dye lasers has work at ORNL arul recently became a research associate with the made it possible for researchers to apply these princi­ University of Sauth Carolina, assigned to the ORNL Physics Division. ples to nuclei with very short half-lives and of very small quantities." ing slits then select mass-separated beams of individual isotopes for study. Nuclear Physics Another interface problem was the collection of the Of the approximately 5000 isotopes thought possi­ mass-separated nuclei and delivery to the measuring ble, UNISOR during its first decade has characterized devices which monitor the decay process to determine, over 50 new ones, establishing half-lives, energies and for example, isotope decay rates and energy losses via intensities of gamma rays, and alpha decay energies, emissions. At first, aluminum-coated mylar tape trans­ and determining masses using positron-endpoint ener­ port systems powered by three motors were used. More gies. recently, the UNISOR staff developed a simplified sys­ During this work one of the important contributions tem using a continuous loop of common 8-track record­ of UNISOR has been the study of nuclear shape. ing tape mounted on a single reel and driven by a single "Nuclear physicists like to study various aspects of motor. nuclei," says Reidinger of UT, "but a recurring theme is Two of the mass-separated beams travel down beam shape. Once that's understood we can then go on and tubes and are focused onto these transport tapes. A understand the finer details of nuclear structure." third beam is collected at the separator. The tapes carry UNISOR made its reputation studying the the deposited nuclei to detectors. mercury-thallium region. "Many new things turned up Because the UNISOR facility is designed mainly for there that we had never seen before," says UNISOR's decay-spectroscopy measurements, various detectors are Mlekodaj. One of these was shape coexistence in even­ used (germanium, silicon, sodium iodide, and plastic) for mass mercury isotopes. In the early 1970s, measure­ energy spectra and timing measurements of gamma ments of the root-mean-square radius of mercury iso­ rays, x rays, conversion electrons, and alpha and beta topes at the European Organization for Nuclear particles. Computer-based systems are used for data Research in Geneva indicated a sudden change in shape acquisition, analysis, and control of the experiments. between the heavier and lighter isotopes, from To aid in the analysis, a nuclear orientation facility mercury-187 to -185. The researchers at UNISOR began has been proposed which will use a magnetic field and looking at many different states of isotopes in this an extremely cold temperature (15 mK) to align the region, first in mercury-188, and then by 1976 with Joe

FALL 1982 11 Hamilton and the Vanderbilt University group, they had moved out to mercury-186 and -184. From these studies, UNISOR accumulated evidence for the coexistence of a nearly spherical shape and a prolate, or football, shape at slightly different energies in each of several mercury isotopes. They had observed crossing spectral bands built on different nuclear shapes. "We were able to see the band members (nuclear energy states) belonging to a given shape both above and below the crossing point in both bands," explains Spejewski. "This was the first clear demonstration that there really was that kind of structure- two states with rotational bands built on them, with different kinds of deformations for the states." All of this was quite unexpected at the time because mercury is close to lead, which has a closed nuclear pro­ ton shell. It was thought that there could not be deformed shapes near closed shells, so finding deformed shapes this close to lead's "magic" proton number was surprising. In their work with odd-mass, neutron-deficient gold, mercury, and thallium isotopes, the UNISOR group with the help of Ed Zganzar of Louisiana State University found, in addition to the near-spherical and prolate Barry Ritchie (left), a 1979 Ph.D. student with the University of Smdh shapes, a nonaxially symmetric (triaxial) deformed Carolina, and Jerry Cole set up a coincidence system which takes shape- something like a flattened football. Finding it in measurements with pairs of detecturs. all three of these elements demonstrated that triaxiality Recently, work with old UNISOR data on the struc­ is a general feature of nuclei in this region. ture of odd-mass gold isotopes has supported the idea of The researchers also found that they could success­ supersymmetry in nature, which is incorporated into fully apply a simple model that described an odd-mass one of the more recent nuclear models, the Interacting nucleus as a single nucleon coupled to a core of tightly Boson-Fermion Approximation. In this model, paired bound pairs of neutrons and of protons. The single par­ nucleons, bosons, interact with an odd fermion, a single ticle in a sense acts as a probe of the structure of the nucleon. Supersymmetry is the case when these parti­ rest of the nucleus and in particular can tell something cles, having quite different properties, behave similarly. about the shape. The model fit the UNISOR data so well John Wood of the Georgia Institute of Technology has that it was used to describe the shape of nuclei and to demonstrated that the supersymmetric scheme of the predict the different kinds of deformations and cou­ IBF A explains much of the systematics of gold-193. plings in the gold-thallium region. In addition, Ken Toth of the ORNL Physics Division Studies with the odd-mass thallium isotopes also has been making a systematic investigation of alpha­ demonstrated that problems existed in the classical particle decay in neutron-deficient isotopes between tin shell model description of nuclei. The researchers and lead. In contrast to the mass region above lead, observed energy states, which should have been up in alpha decay in this region is rarely observed; although the next-higher shell in the shell model, moving down most nuclei between tin and lead are alpha-particle and intruding into the next-lower major energy shell. If unstable, their decay energies are small enough to make a simplified view of the classic shell model were correct, their alpha decays difficult to observe. As these nuclei these states could not have existed at such a low energy. become more neutron-deficient, however, their decay This was an experimental demonstration that the shell energies increase and alpha decay begins to be observ­ model and magic numbers depend on the position of the able. "Measuring an alpha-particle energy gives us a valley of stability. If the region of stability had hap­ handle on the mass of the nucleus we're looking at," pened to extend through a different group of nuclei, it says Toth, "which is something that gamma-ray studies might not have been so easy to recognize a pattern of don't normally provide. Alpha-decay energies therefore magic numbers to formulate a nuclear shell model. In give us an excellent way to test predictions of mass in fact, the magic numbers are not magic far from stabil­ nuclei far from stability. I should also add that alpha ity. decay is an extremely convenient way to identify new

12 OAK RIDGE NATIONAL LABORATORY Review 128

1- -

112 1- - Neutron Rich 1- - Neutron 96 1- Deficient / / ..... / / - z / / ... / C1l / .0 80 1- / - E / :I / / 1- / z / / c: / 0 / ... / ... 641- / - :I / C1l / / z / 1- / - / "1.­ /~ ~ 48 1- / - / / ... . / 1- .. : . // - .. :·· // :·· // 32 1- ... / - . :=:-:/:/ .. " / 1- .. : / .. : ./ -

16 1- -

1- Gene Spejewski, director of UNISOR, and Ken Carter of the UNISOR stall discuss an experimental run at the isotope separator control con­ 0 . ~. l I I I I I sole. 0 16 32 48 64 80 96 isotopes whose properties can then be examined in more Proton Number Z detail by using other techniques." The proton and neutron numbers of the stable nuclei define the valley of stability. To one side of this stability line, unstable nuclei are neutron Moltz of ORNL has been involved in positron end rich; to the other side, neutron deficient. Exotic nuclei to either side point energy studies, which determine mass differences decay by beta emission, each, in effect, becaming a different chemical following positron decay. A positron spectrometer for element, until they reach a proton-neutron e

FALL 1982 13 shown that every time we're able to expand the region beams from reactors, some nuclear reactions with heavy so that we can make more experimental measurements, ions produce nuclei that are neutron rich. So far, how­ we find something different and interesting." ever, UNISOR researchers have been unsuccessful in The higher-energy beams from the tandem accelera­ producing any. With the heavier ion beams from the tor will make it possible to extend the mercury studies tandem accelerator, they will try again. to the lighter 182 and 180 isotopes. And the heavier cal­ "We'll continue to increase the capabilities of the cium beams can be used to produce the 184 and 186 iso­ facility," says Spejewski, "so that we will be able to look topes of lead. in any new directions that appear important in the light In addition to the Z = 82 region of lead, the Z = 50 of new ideas or experimental results. By developing the region of tin should also be rich in nuclear structure technology, we hope to be able to take advantage of the information. Theoretical calculations show that another possibilities of finding new and interesting physics." interesting area contains the neutron-deficient cerium "A major accomplishment of UNISOR in its first nuclei. Positron end point energy measurements, alpha­ decade," says Paul Stelson, director of the ORNL Phys­ decay measurements, and laser hyperfine structure ics Division, "has been to bring together nuclear physi­ measurements will continue. The helium-gas jet system cists from the ten or so universities which were some­ will be used to try to discover new nuclei farther from what isolated and lacked the facilities to do interesting stability. experiments. By coming together, they were able to The UNISOR group would also like to produce nu­ build up a set of equipment and techniques that is com­ clei with a neutron excess-all they have studied thus petitive on a worldwide basis. UNISOR transformed the far have been neutron-deficient nuclei. Although neu­ way nuclear physics is done in this part of the country. I tron-excess nuclei are usually produced using neutron see a bright future." c:ll

GLOSSARY NUCLEAR SPIN- Because neutrons and protons behave as though they are spinning, nuclear spin is the result of the spins of the neutrons and protons of which the BET A DECAY -An unstable nucleus decays by nucleus is composed and is represented by either an undergoing spontaneous transmutation involving integral or a half-integral number. The spinning nucleus transformation of a nucleon and beta emission; depending possesses an angular momentum. on whether the nuclide is neutron rich or neutron deficient, either (1) a neutron within the nucleus decays NUCLEONS- The constituents of the nucleus, the to a proton by emitting an electron and an antineutrino or protons and the neutrons, are referred to by the general (2) a proton within the nucleus decays to a neutron by term, nucleon. emitting a positron and a neutrino. PARITY-Only in wave mechanics can a system of CLOSED SHELL-In the nuclear shell model, a shell is particles possess parity, which describes how the mirror filled, or closed, for nuclei near stability when the number image of a system behaves; parity is positive if the mirror of neutrons or protons equals a magic number (see image is the same; negative if it is different. MAGIC NUMBERS). POSITRON END POINT ENERGY -Because the total GROUND STATE-Atoms or nuclei in excited states tend energy released in beta decay is shared by the two to return to the ground state, the lowest possible energy emitted particles, the energies of the positrons are not state of the system. distinct but form a continous spectrum. The maximum is the end-point energy and represents the total energy HYPERFINE STRUCTURE- The interaction of the atomic released in decay. nucleus with the atomic electrons causes a shifting, or splitting, of the atomic energy levels and is seen under ROTATIONAL BAND- A deformed, or nonspherical, high resolution as a hyperfine structure of the atomic nucleus can rotate about its nonsymmetrical axes, energy spectrum. causing a flopping motion; the allowed energy states of such rotations cause a distinct pattern, a rotational MAGIC NUMBERS-The binding energies of a nucleus pattern, in the energy spectrum of the nucleus. are unusually large if the number of neutrons, protons, or both is one of the magic numbers 2, 4, 8, 20, 50, 82, or z-The symbol Z is used to denote atomic number, that 126. is, the number of protons in the nucleus.

14 OAK RIDGE NATIONAL LABORATORY Review The author of Polywater is Felix temperature of the liquid, that is, Franks, well known to chemists and which would not return heat to a others as the editor of a thermometer (or a finger) at a multivolume treatise on water. The slightly lower temperature when dust jacket notes that he is known immersed in the liquid. in the trade as "Water Franks," An apparent bit of irony trips up and in the text he admits to having the author at another point. In BOOKS acquired the label of water expert. discussing Ellis Lippincott, the As far as I can tell, Franks has spectroscopist whose paper brought the history straight. Further, he polywater fever to the United provides information not easily States, he lists Lippincott's Polywater, fly Felix Franks, available otherwise on unpublished credentials, including the fact that MIT Press (1981). 208 pp., $15.00. activity by the British in the field. he had been awarded the Reviewed fly EUistm Taylor, However, be careful what you "Hildebrand" medal. "This turned consultant to the Chemistry DivisWn. believe. Many of his explanations out to be particularly ironic because for the nonscientist and other items Joel Hildebrand, one of America's ~ bout ten years ago, the short, of information are completely premier chemists, was to take a a==llsilly life of polywater came to wrong. quite uncompromising stand an end, not with a single clean shot, After a prologue, Franks begins against all his fellow scientists who but with the steady accumulation of with an introduction to the had been naive enough to take evidence that everybody's samples properties of ordinary water, one of Deryagin seriously." The real irony of supposed polywater were simply them being the specific heat. Here is that Lippincott's medal was the samples of water contaminated he propounds a rule:"... and yet "Hillebrand" medal, named for with salt, silica, sweat, or what another rule states that the specific William Francis Hillebrand, the have you. heat of a solid is higher than that famous analytical chemist at the In case you've forgotten, of the same substance in the liquid National Bureau of Standards a "polywater" was one name given to state." None of my chemist friends generation ago. Given by the a supposed new form of liquid has ever heard of this rule, and a Washington, D.C., Section of the water thought to be discovered in casual search turned up 17 American Chemical Society, it is a Russia in the early 1960s. N. N. inorganic compounds that follow natural for a prominent chemist at Fedyakin started it with a paper, the "rule" and 54 that do the the University of Maryland. "Changes in Structure of Water reverse. With organic compounds, Franks ridicules the American Condensed in Capillaries." He and the score was 0 for and 5 against. press for playing up American vs his research moved almost at once Some rule! It is true that water Russian contributions, but he from Kostroma to the Moscow shows a wider difference than most chooses an unfortunate example. He Laboratory of B. V. Deryagin, a substances, but it is merely an says, "The more subtle way of surface chemist of wide fame who extreme example of the usual searching for a non-Russian became the chief protagonist of behavior, not an exception to any originator of polywater is what they called "modified water." rule. exemplified by an in-depth account In June 1969 a group led by Ellis Franks gets into even worse of polywater in the Saturday R. Lippincott of the University of trouble when he tries to explain the Review of September 6, 1969. Here Maryland published infrared and high specific heat of water. He we are told about an American Raman spectra of a similar points out correctly that the chemist, Walter Patrick.... One of material and proposed both a specific heat of ice is about half Patrick's students, a Russian polymeric structure and the name that of liquid water, and then says, immigrant named J. L. "polywater." For a few months, "... when energy is supplied to Shereshefsky... found that water polywater attracted the attention of liquid water, only half of it is used in capillaries had an even lower such publications as the New York to raise the temperature; the vapor pressure than that predicted Times and the Wall Street Journal, remainder is stored away in the from its curvature by the Kelvin but within about a year, it was bulk of the liquid." He seems to equation .... This manner of shown to be ordinary water having believe that there are certain tracing developments back to their dissolved impurities-just a brief degrees of freedom in water ("the true origin is fairly aberration of science, quickly bulk of the liquid") which can pointless .... Quite apart from this, discovered by the usual process of somehow absorb heat but do not Fedyakin, working on his own in repetition. participate in exhibiting the faraway Kostroma, must have been

FALL 1982 15 completely unaware of the prevailing in faraway Kostroma. uncovering error. And, on the existence, let alone the work, of one I have not discussed the more subject of polywater, self-righteous Walter Patrick." The fact is that general aspects of the book. is what I am, according to Franks, the first reference in Fedyakins's Perhaps I should have ignored the in my article "The Great Polywater first paper is to Shereshefsky. So mistakes, but nothing is more fun Doodle," ORNL Review, Winter much for the presumed ignorance for the self-righteous than 1971.

Resources and Development, Peter Dorner and Mahmoud ElrShafie, pertinent and may be particularly eds., The University of Wisconsin Press (1980) , 506 pp, $25.00. Reviewed by A. useful to staff members having D. Kelmers, Chemical Technology Division. interests in the strategic materials/resource recovery areas. Two aspects of the minerals and (5(5 ~ mong the features often or two decades. The authors com­ metals industry mentioned are par­ ~ observed in areas of shrink­ pare the experience of the past ticularly relevant. Although no ing resource production are per­ decade with the predictions of such resource limits exist, there is a sistent unemployment, uneven models. Experience showed some­ maldistribution on the earth's sur­ economic response (even to sharply thing quite different: Exploration face. For example, the world increasing prices), frequent year­ for minerals and even for oil has chromium supply is concentrated in to-year instability in production, outraced consumption. Not only has South Africa, cobalt in Zaire, plati­ and technological stagnation." consumption not increased exponen­ num in the Soviet Union, and coal When I opened this book on the tially, the rate of increase for most in the United States. Maintaining New Book Shelf in ORNL's Central resources has actually decreased. easy world access to the resources Research Library, this quote caught For many minerals and metals, the is a political problem and is not my eye. Nothing could better long-term trend is toward amenable to a technological fix. characterize the domestic minerals decreased per capita consumption Also, the authors state, there are and metals industry. Resources and in the United States. Thus, no " ... two main categories of techno­ Development is a compilation of limiting resource crises exist. logical change of interest in contributions to a seminar on The authors accept that all non­ mineral production: (1) industry­ Natural Resource Policies held at renewable resources are finite. specific advances that increase the University of Wisconsin in However, they point out that resource availability or lower costs 1977-1978. The presentation is attempts over the past 30 years to or both [and] (2) application to unusually lucid, and the book con­ predict when limits might occur mineral production of general tech­ tains a new and perceptive view of have been so poor (nearly all pre­ nological advances .... Only the long-range aspects of resource dictions have been wrong, some first kind of technological change availability. dramatically so) that the best that might be stimulated by increased The seminar took a new approach can be said at this time is that we market prices for mineral raw to problems of resource develop­ do not know how to make such materials. Unless (or until) raw ment, and the chapters contain predictions. For example, over the materials and energy constitute a many new and exciting ideas-some last decade not only has the amount much larger fraction of the total of which may be relevant to of copper in proven reserves cost of final products, it is wishful ORNL's Strategic Materials/ increased, but even the grade of thinking to suppose that increased Resource Recovery activities. The copper ore has improved. Also, difficulties in mineral production "Club of Rome" impending-crisis despite a doubling of crude oil con­ will by themselves bring about approach to future resource and sumption each decade, proven broad-front technological change of demand limits, which was in vogue reserves have continued to expand the second type." in the early 1970s, is refuted. Based more rapidly than consumption. In Subsequent chapters discuss on the existing information on the uranium industry, consumption market structure, economic and known reserves (for minerals, fuels, in the 1980s and 1990s will be much social development, food and popu­ or foods) and an exponential lower than predicted, making pro­ lation, international order and law, increase in consumption, this ven reserves of uranium ores now and socioeconomic-resource model­ approach showed that, for most appear adequate to last until well ing studies. The final chapter resources, a supply-availability into the next century. addresses the question of "Resource crisis which would limit future Chapter 2, "Availability of and Developmental Policies." The growth would develop in only one Mineral Resources," is especially authors recognize that rapid popu-

16 OAK RIDGE NATIONAL LABORATORY Review lation growth and the desire of new use and consumption). They suggest seminar was cosponsored by the nations for more rapid economic joint action and international Organization of Arab Petroleum growth and development have cooperation-some sort of "global Exporting Countries, the Arab brought a fundamental change in compact" to administer power and Fund for Economic and Social resource use and availability. They eliminate resource-development Development, and the Kuwait Fund suggest that novel policies will be abuse. Research on policy questions for Arab Economic Development. required to deal with resource is vital to a determination of Nonetheless, developing nations are issues and that free trade can no developmental strategies and poli­ in a position to make their voices longer be expected to do an accept­ cies in the public interest. heard in the future on resource pol­ able job (i.e., price cannot be the To some extent these conclusions icy, and it would be to our advan­ only agent for determining resource may be seen as self-serving. The tage to be aware of their views.

Books in Print Scientific Basis for Nuclear Waste Defects in Semiconductors, J. The following books now in print Management, Vol 3, John G. Moore, Narayan and T. Y. Tan, eds. have been written or edited ed. Plenum Press, New York (1982). North-Holland, New York (1982). primarily by ORNL staff members: Introduction to Nuclear Reactions, Analytical Chemistry in Nuclear Laser and Electron-Beam G. R. Satchler. John Wiley & TechnoWgy, W. S.Lyon,ed. Ann Interactions with Solids, B. R. Sons, New York (1982). Arbor Science Publishers, Inc., Ann Arbor, Mich. (1982). Appleton and G. K. Cellar, eds. Advances in Molten Salt Chemistry, North-Holland, New York (1982). Vol 4, Gleb Mamantov and J. Proceedings of the Second Histological Atlas of the Laboratory Braunstein, eds. Plenum Press, New International Symposium on Molten Mouse, William D. Gude, Gerald E. York (1982). Salts, Jerry Braunstein and J. Cosgrove, and Gerald P. Hirsch. Robert Selman, eds. The Plenum Press, New York (1982). Water Chlorination: Environmental Electrochemical Society, Inc., Impact and Health Effects, Vol 3, Pennington, N.J. (1981 ). Light Water Reactor Nuclear Fuel Robert Jolley, William A. Brungs, Cycle, Raymond G. Wymer and and Robert B. Cumming, eds. Ann Mechanisms in Respiratory Benedict L. Vondra, eds. CRC Press, Arbor Science Publishers, Inc., Ann ToxicoWgy, Vol II, Hanspeter Boca Raton, La. (1982). Arbor, Mich. (1982). Witschi and Paul Nettesheim. CRC Press, Boca Raton, La. (1981).

On the matter of the cigarette lighter, there is no readers' comments problem with a flywheel-containing system. Just as one can have high acceleration rates, one can have any size lighter one wishes up to a multihorsepower plasma torch, as long as there is a healthy time interval between To the editor: smokes. The problem comes from such persistent John Googin's article on the flywheeled automobiles energy-consuming devices as headlights and high­ and the high mileages obtainable (Fall 1961) was powered speakers for the radios and tape players. These dynamic and good reading. However, one question arose could considerably reduce the mileage and the cruising in my mind: does such a car have a cigarette lighter? speed. The human element enters; the mileage achievable might The car of the future should have a minimum of depend upon whether or not the driver is a smoker. efficient lights and a maximum of reflectors. It should have individual headsets for the music system and no A. H. Snell, consultant regular speakers. Physics Division With good insulation and double windows there should be no problem with heating, but there is a cooling Author Googin replies: problem. Perhaps the comfort problem in hot weather will Art Snell's comment on the implications of the low be solved by using the small amount of waste heat from energy requirements of the possible future car is most the power plant to supply dry air to allow full use of the stimulating. occupants' personal cooling systems.

FALL 1982 17 An oil company's drilling rig, rising against a backdrop of Wyoming mountains, embodies the tension between resource development and wilderness preservation. This rig is next to a 'JIT'U.P08€(l wilderness tract; the U.S. Farest Ser­ vice recommends allowing explqratqry drilling within the tract itself. (Photograph by Chip Rawlins.)

i era i I r • how important are they? • •

by JON JEFFERSON

I'F))icture yourself overseeing mil­ several of the smaller eastern hunting, and other recreational .!r"'lions of hectares of federal states combined. opportunities. It harbors deposits of land in the western United States. The land currently provides graz­ oil and gas, uranium, and coal. And It's your job to plan the uses for ing range for cattle and sheep. It some of the land embodies the qual­ the land in a district larger than yields timber. It offers camping, ities Congress had in mind when, in

18 OAK RIDGE NATIONAL LABORATORY Review Ed Oakes, center, and Al Voelker, far right, discuss preliminary resource evaluations with Bureau of Land Management sto!f in Moab, Utah. BLM staff, from left, are geologist Jim Piani, land manager Pete Christensen, and wilderness ooardinator Diana Webb.

have testified on some of their find­ ings to a congressional subcommit­ tee investigating the desirability of opening wilderness to mineral development-a move proposed by Interior Secretary James Watt but later dropped. Although, as consultants, Voelker and Oakes are not directly respon­ sible for land-use decisions, they 1964, it created the National Wil­ your recommendations, they will have experienced firsthand some of derness Preservation System. certainly take you to task-maybe the tensions involved. They told the The Wilderness System now to court. Capitol Hill subcommittee, for includes about 30 million ha (80 Such is life in the western dis­ example, that there is little reason million acres) of protected land. trict offices of the Bureau of Land to open existing wilderness areas to During the next decade, up to Management, the Department of development, since these areas con­ another 10 million ha (24 million the Interior's steward of more than tain only an estimated 3% of the acres) may be added. The possible 160 million ha (400 million acres) of nation's undiscovered oil and gas additions include nearly a thousand government-owned land in the resources. That testimony, which Wilderness Study Areas, which western states and Alaska. countered the figures quoted by range in size from a few hundred to ORNL/SAI Method Evaluation would-be energy developers, made a few hundred thousand hectares. the head of a national mining­ In reviewing the thirty WSAs in To assist in the large, complex, industry group "so mad at us he your district, you must consider the and sometimes controversial job of won't even return a call," says potential uses of each one and deciding which WSAs should be Voelker. determine whether the area is most preserved, a technique developed by The ORNL/SAI project dates suitable for wilderness or for other, ORNL and Science Applications, back to 1978, when the U.S. Forest less restricted uses. Inc., is being used. The technique, a Service was surveying large road­ The task is somewhat akin to way of evaluating an area's less areas of its lands for possible walking a barbed-wire fence. On energy-resource potential, was inclusion in the Wilderness System. the one hand, you must consider developed mainly by AI Voelker of The Forest Service, like BLM, must the importance of the wilderness ORNL's Energy Division and Ed consider energy and mineral attributes of the tract: its scenery, Oakes of SAL resources in its land-use decisions. wildlife, and opportunities for soli­ The ORNL/SAI Resource Evalua­ The Department of Energy became tude or primitive recreation. On the tion Method has already been involved because one of DOE's main other, you must weigh the value of applied to more than 3 million ha functions is to encourage the or­ keeping the land available for graz­ (7 million acres): Bureau of Land derly development of U.S. energy ing or lumbering, recreational vehi­ Management tracts, U.S. Forest resources; DOE is mandated to cles, or-often most controversial in Service lands, and areas along comment on all federal programs the mineral-rich West-mining and rivers being considered for the and actions that may reduce the drilling. National Wild and Scenic Rivers availability of publicly owned Scrutinizing your decisions and Preservation System. BLM has energy resources. DOE's Office of recommendations about the WSAs recently adopted the method in a Resource Applications asked ORNL are enthusiastic-sometimes proposed assessment guidebook for to develop a method for evaluating rabid-people from both sides of its geologists. Voelker and Oakes the energy resources of these poten­ the fence: preservationists and have described the method to a tial wilderness areas. In 1979, prospectors, wilderness groups and National Academy of Sciences com­ when the Forest Service completed oil companies. If they disagree with mittee on resource assessment and all its wilderness reviews, BLM

FALL 1982 19 The energy-rich regions shaded on this map include many Wilderness Stwly Areas. An ORNL/SAI stwly recommends accelerated stwlies of these WSAs.

became the main user and a co­ sponsor of the project. A Realistic Alternative The most important feature of the ORNL/SAI Resource Evalua­ tion Method, say Voelker and Oakes, is that it's geared directly to the needs of the typical land D OILANDGAS ~ COAL manager, who often has to make ~ URANIUM fast decisions about the fate of IIL~-~1 GEOTHERMAL large tracts of land. Ideally, land-use decisions that money are short. It's also a good affect mineral resources should be way of identifying areas where based on detailed field explorations. more detailed studies would be In wilderness planning, however, worthwhile. reality is most often a pressing Resource Ratings schedule and a tight budget. For example, the Department of the The heart of an ORNL/SAI Interior legally has until 1991 to evaluation is a set of simple numer­ complete its wilderness reviews, but ical ratings that indicate at a Secretary James Watt wants the glance the importance of an area's reviews finished within two years, resources, separately and as a even though no extra money is whole. The ratings allow immedi­ available to speed up the schedule. ate comparison of the resource What's more, thorough exploration value of different areas, even if the requires the drilling of numerous kinds of resources are not the same. test holes, which can compromise Besides the ratings, the evaluation the very qualities valued most in provides several levels of referenced wilderness. technical data-a "pyramid of By contrast, the ORNL/SAI information" whose top is clear and method is fast, inexpensive, and useful to a nontechnical manager nondestructive. The method relies and whose base is credible to a pro­ on existing geologic data instead of fessional geologist. Lynn Jackson, field exploration. "We wanted to the staff geologist for BLM's Moab find a way of doing credible work District (in southeastern Utah); interpreting, and summarizing the within the budget and time con­ calls the rating system "a straight­ geologic data. A core team of two straints that land managers operate forward way of relaying informa­ or three resource geologists is under," says Oakes. "Field assess­ tion to a nontechnical person, one organized at the start of each ments take two to three years per that's helped our management quite evaluation, with additional consul­ district and cost about $12 an acre; a bit. Having tried to write some of tants or part-time staff added our method takes about six months these resource assessments earlier whenever needed. ORNL and SAl and costs about twenty cents an myself, I was quite impressed with have provided the core team in all acre." Although the evaluation their method. I wish I'd had some­ resource assessments so far. "We're results are not as definitive as field thing like it to guide me." not particularly interested in doing exploration, the method is a realis­ The method uses a highly sys­ one after another," says Oakes, "but tic alternative when time and tematic approach to gathering, it gives us a foundation for improv-

20 OAK RIDGE NATIONAL LABORATORY Review Time and weather have uncovered uranium­ bearing ure (dark bands) in this jcn-mation within a proposed wilderness area in Capitol Reef National Park, Utah. The road is excluded from the proposed wilderness area.

back and see things in a regional or national context. Besides, it's easy to get carried away by the euphoria of a discovery or by the weight of someone's opinion unless you have some way of checking yourself." Once familiar with the geology of the region, the core team character­ izes the district itself in terms of its past and present production and, by looking at analogous areas else­ where in the world, its potential for the future. The team plots resource occurrences on overlay maps, out­ lining favorable geology to show areas of promise within the district. Then it locates and studies the available information about the characteristics of each WSA, such as size, location, water resources, accessibility, and terrain. The team works together closely, so that its members will share a common understanding of the area's geology. Consensus is one of the method's cornerstones: "The test of our work is whether we've presented an understanding of an area, one that most geologists fa­ miliar with the area would agree with," says Voelker. The team then discusses its preliminary conclu­ sions with the BLM district staff members. The final evaluation may be adjuste.d to reflect their judg­ ments, because they will have to ing the method. That's the way we Starting with broad, regional­ defend any recommendations that test our design and our understand­ scale references such as U.S. Geo­ are challenged. ing. We're brought back to reality logical Survey maps and reports, After the team has gathered and by it sometimes." the team gradually narrows its interpreted the data (sometimes Besides Voelker and Oakes, the focus to data about the individual from as many as a hundred sources core team includes Helmuth WSAs. This approach ensures a for a single WSA), it develops the Wedow, a Knoxville geologist on broad perspective. "The BLM people numerical ratings. subcontract to the project; others are busy policing the district," says helping with the evaluations are Oakes. "They deal with individual Measures of Importance Robert Poling, an SAl geologist, companies, individual drill holes, and Paul Intemann, a geologist in and individual permits, so it's The method provides dual ratings ORNL's Energy Division. sometimes hard for them to step for individual resources: oil and

FALL 1982 21 (jqunty officials in Moab, Utah, had this lndldozer cut a swath into a proposed Wilder­ ness Study Area, hqpi'TIQ to furce its removal jrum the BLM study. (Photograph IXlUrtesy of Moab Times-Independent.)

According to the ORNLI SAl evaluation, some of the Moab WSAs-including Negro Bill Csnyon-have fairly high potential for oil and gas; some may contain large uranium deposits and a good bit of potash. The coordi­ A Bulldozer for Emphasis: nator of the Moab District's wilderness reviews, Diana 11 Webb, explains how such resource potential complicates The stakes are really high" BLM's job: "We have a very polarized public out here. Half the people are wildly in favor of designating as much wilder­ One of the current proving grounds for the ORNLI SAl ness as possible; the other half are wildly in favor of Resource Evaluation Method is Utah, which is divided into designating no wilderness, and of removing national parks five Bureau of Land Management districts. Utah's excep­ as well. tional scenic beauty and large undisturbed areas make it "A lot of people here make their living looking for one of BLM's high-priority areas for wilderness review. minerals. If they can't go in and stake claims, they see a The study of the Utah Wilderness Study Areas is to be potential loss of income. On the other hand, if uranium is completed next spring. found on their claim, they can make a million dollars over­ The Moab District (named for the small, eastern Utah night. The stakes are really high; that's why people feel town where it's headquartered) contains 2.5 million ha so strongly." (6.5 million acres) of BLM lands-an area nearly one­ The ORNL/SAI Resource Evaluation Method may help fourth the size of Tennessee. The district's thirty one ease some of the tensions, according to Webb. "We WSAs contain about twice the land in the Great Smoky have a difference between the perceived mineral values Mountains National Park. and the actual mineral values. We hear a lot of 'Every­ One of the proposed Moab WSAs, Negro Bill Canyon, body knows that area is full of uranium (oil, gas).' Having has become a local cause celebre in the conflict between an outside study gives us a way to counter those percep­ preservationists and would-be developers. In 1979, when tions." BLM was deciding what areas were suitable as WSAs, Why an outside study? "Out here, people on both local officials had part of the Negro Bill Canyon area sides distrust BLM. So having an outside agency come in bulldozed, hoping to render it ineligible for consideration. lends some credibility to our recommendations. It also The tactic didn't work, but BLM later decided that state­ gives us a fresh perspective." owned land in the canyon would make it unsuitable as There is yet another reason why good resource federal wilderness; however, a Sierra Club suit to the evaluations are important to Webb and her colleagues: Department of the Interior's Board of Land Appeals won when BLM's evaluations of mineral resources and other the restoration of most of the area to the wilderness factors indicate that an area is suitable as wilderness, study this spring. the U.S. Geological Survey and the Bureau of Mines must The local county commission, unhappy with the res­ then make a detailed mineral assessment of the area. As toration, charges that BLM is refusing to acknowledge Webb notes, "Obviously we don't want to be in the posi­ the existence of a road in the area. According to the tion of having said 'This area doesn't contain any impor­ Moab Time9-lndependent, the commission has threatened tant resources' and then have USGS or BM say 'Yes it to grade the road "to emphasize its existence." does."'

22 OAK RIDGE NATIONAL LABORATORY Review gas, coal, uranium, geothermal such as accessibility, economics, uranium (f3/c2), and potash (f3/c3). energy, and hydropower, plus any environmental constraints, and Less important are copper and other minerals thought to be national needs and priorities. manganese (each f2/cl). Coal and important in the area. To understand the need for the geothermal are each rated fi/c4. The first part of each rating indi­ OIR, consider the task facing the Narrative sections justifying each cates the area's favorability for the land manager who must evaluate rating in detail follow. The report resource: high, moderate, low, or the resources of thirty WSAs. If concludes with a listing of the most none (f4, f3, £2, or fi, respectively). each of those areas has dual ratings useful references on the area's The second part indicates the for five resources, the manager resources-for Negro Bill Canyon, degree of certainty that the must in effect assimilate and bal­ the report lists 46-and maps show­ resource actually exists (or not) in ance 300 ratings before having a ing the favorable zones for each or near the tract: from highly good understanding of the region's resource and the location of mines, certain (c4) to uncertain (cl). The relative resource potential. The OIR oil and gas wells, and other best resource rating for a WSA is simplifies the task considerably. resource-related features. therefore f4/c4, a rating that indi­ Because it reflects many factors, Besides Negro Bill Canyon, there cates a high geologic favorability some of which defy numerical are thirty other WSAs in the Moab and high certainty. The worst is weighting, the OIR is necessarily District. Each WSA is the subject fi/c4, a very unfavorable rating more subjective than the individual of a similarly structured report. about which there is little doubt. ratings. Deriving the OIR Some of the reports, especially (An f4/cl rating, high favorability mathematically was a tempting those on neighboring WSAs, may but very low certainty, suggests alternative but, say Voelker and contain much the same informa­ that a more detailed study might be Oakes, the available data are too tion, but each report is written so worthwhile.) limited and often too unreliable to that it can stand alone; that feature The criteria for favorability and justify such a rigid approach. The makes it easier to focus discussion certainty ratings are defined as method is meant not as a cookbook, on WSAs of particular uncertainty, objectively as possible for each but as an aid to judgment. Like the controversy, or interest-like Negro resource. An f4 rating for oil and favorability and certainty ratings, Bill Canyon (see box). gas, for example, requires geologic the OIR is derived with the aid of ''You never know everything" evidence that suggests the area con­ carefully defined rating criteria. tains more than 8 million m3 (50 Theoretically, the OIR could be The reports on Negro Bill Canyon million bbl) of oil or more than 8.5 affected by biases and mispercep­ and the other Wilderness Study billion m3 (300 billion ft3) of gas. A tions. In practice, though, the Areas are not, Voelker and Oakes c4 certainty rating for oil and gas is method's systematic criteria, its stress, definitive evaluations. used only when there is abundant emphasis on consensus, and its pro­ Rather, they are attempts to syn­ direct evidence of occurrence (e.g., visions for external review serve as thesize and present, as clearly as productive wells, oil seeps, and tar safeguards against bias. possible, the available data. "We've sands) or nonoccurrence (e.g., dry never said that ten years from now, test holes). Similar objective cri­ An Example what we've said will still be right," teria guide the ratings for the other Consider the evaluation report says Oakes. "But you get the best resources. Because these criteria for one Wilderness Study Area: information you can right up to the are central to the success of the Negro Bill Canyon, in Utah's Moab decision point, then you make the method, most of the development District. The report first identifies decision and stand by it. Later, if time in the project has been the tract and gives its location and your information or needs change, devoted to perfecting them. size. Then it describes the geologic you can reevaluate these decisions. After reaching a consensus on features of the tract and the sur­ "Most other resource-assessment the individual resource ratings, the rounding area. Next come the methods are very data oriented. core team rates the overall impor­ resource ratings. They say, 'Don't make a decision tance of the area, also on a high­ Negro Bill Canyon has an unless you know everything.' Of to-low scale of 4 to 1. The overall­ overall-importance rating of 3 course, you never know everything. importance rating (OIR) syn­ minus: fairly high, but less so than Our method is different in its sensi­ thesizes the individual favorability other 3-rated areas because of its tivity to the needs of the land and certainty ratings, as might be limited size and accessibility. Con­ manager, who has to make-and expected, but also reflects other tributing to the fairly high OIR are defend-decisions on the basis of factors not previously considered, the ratings for oil and gas (f3/c2), the available information." m:!l

FALL 1982 23 because of indirect costs and interest rates. However, Delane and his associates found that this cost difference is offset in the East information meeting highlights by the fact that nuclear fuel Is more econom­ ical than coal, natural gas, or oil. Says Delane: "Nuclear fuel is the economic choice over coal for baseload because of flaws such as unwanted vibra­ l:ngln-rlng Technology, electric power generation at the eastern tions, lack of balance, material failure, and March 25-H location, and coal is the economic choice at premature cracking. the western location. At both locations, Flywheel lvaluatlon In some cases, ORFEL results have baseload power generation by either natural guided flywheel developers in redesigning gas or oil is more expensive than either In the age of declining oil supplies, the flywheels whose flaws showed up only after nuclear- or coal-fired generation. • search Is on for innovative ways to make high-level testing in that facility. For example, automobiles fuel efficient. One of the Steele was able to detect relative motion approaches supported by the Department of between the disk and hub of the GE Fusion l:nergv Dlv181on, Energy been the development of light­ April has flywheel. The elastorneric joint between 5-e weight flywheels. devices store These these parts has now been redesigned using energy during periods of excess supply by the data and suggestions offered by his test Tokamaka: Reeulb and Plan• increasing the kinetic energy of a spinning engineers. Concludes Steele: "Flywheel H doughnut-shaped fusion reactors using wheel. H effective transmission systems are development has been speeded by ORFEL's magnetic confinement are to be cost effec­ developed, flywheels should be able to store commitment to the performance of energy when the car is slowed or stopped tive as a source of electricity, they must be comprehensive tests that produce high­ return as much as 90% of that energy able to attain high beta. Beta is the ratio of and quality, quantitative results. • when that vehicle is subsequently the reacting plasma pressure to the mag­ accelerated. netic pressure. Recent results from ORNL's Flywheel systems using metallic rotors Which 18 Cheaper: Coal or NuciNrf Fusion Energy Division are encouraging the have been built, but tests show that they belief that betas at a reactor-relevant level generally are unsafe, too heavy, and not par­ H you were an executive of an American may be achieved soon in the tokamak pro­ ticularly economical. Several industries are electric utility company and had been asked gram. now developing lightweight flywheels made to decide whether to order a nuclear-, coal-, For the past two years, a substantial of fibers held together with epoxy. It is oil-, or gas-fired power plant next year for theoretical and experimental effort on the believed that some of these composite startup in 1995, which choice would you Impurity Studies Experiment (ISX-B) has flywheels have the potential to be safe, to consider to be the most economic? been directed toward explaining an apparent store sufficient energy without an overriding H you consulted Jerry Delane, an ORNL saturation in beta. Previously, it was thought weight penalty, and to be cost effective over engineering economist, he would tell you this: that beta would rise linearly with increased the lifetime of the automobile. Avoid oil- and gas-fired plants because future neutral-beam power used for heating the To find out which flywheel designs are supplies are precarious and prices will con­ plasma (a superhot gas composed of hydro­ likely to meet these criteria, Union tinue to rise. Go with nuclear power if your gen nuclei and electrons). ISX-B data in Carbide-Nuclear Division engineers led by utility Is in the eastern United States. H you 1981, however, indicated that beta trails off Robert S. Steele have tested a variety of are located in the Rocky Mountains states, instead of rising proportionately with beam composite wheels in the Oak Ridge Flywheel choose coal. Delane, however, would power. Evaluation Laboratory, which was developed emphasize that social, political, and financial Among the possible causes of the degra­ by DOE's mechanical energy storage pro­ factors may change the decision. dation of plasma confinement are resistive gram for this specifiC task. The flywheels In an ongoing study, Delane and his col­ instabilities of the plasma-magnetic field sys­ are tested to failure, to determine their max­ leagues have kept an eye on the ever­ tem, which can increase heat conduction to imum speed or the maximum number of changing picture of capital investment costs, the wall. A theoretical study, involving per­ cycles attainable between two speeds. operation and maintenance costs, coal sonnel from the Computer Sciences Division Changes in flywheel dimensions, shape, prices, and nuclear fuel costs in two and collaboration with the University of structure, stability, and temperature are areas-Boston and Denver. Their data indi­ Texas, has led to the development of a for­ recorded for detailed analysis following the cate that coal prices vary widely from region mula for an enhanced thermal diffusion rate destructive testing. Recording devices to region and even within a given geographic which results from instability-generated fluc­ include x-y plotters, tape recorders, high­ region. High-suHur eastern coal is currently tuating magnetic fields. Experimentally, simi­ resolution television cameras, and computer­ more expensive in the East than low-suHur lar fluctuations are seen and the measured ized data-acquisition equipment. western coal is in the West. Coal-fired sys­ diffusion coefficients agree well with theoreti­ ORFEL tests showed that the flywheels tems in both regions require installation of cal predictions. The encouraging feature of designed by Garrett AiResearch Corporation costly flue-gas desuHurization equipment to this result is that the problem should be and General Electric Company have the keep pollutant emissions within legal bounds. alleviated in more powerful tokamaks which potential of meeting the desired criteria; thus The capital cost of nuclear power plants use stronger magnetic fields and higher tem­ these are being studied during this fiscal was found to exceed that of coal plants, as peratures. Both the magnetic system and the year. Other flywheel designs were rejected well as other types of plants, principally heating system in ISX-B are being increased

24 OAK RIDGE NATIONAL LABORATORY Review Murray Rosenthal, ORNL A880Ciate Directm far Advanced Energy Systems, explains a model of the Large Coil Test Facility to (from left) Sen. Hcrward Baker, Tennessee Gover­ nor La'TIUlr Alexander, and Robert J. Hart, 'TIUlruJDer of Oak Ridge Operations. Roger Hibbs, President of Uni

The $36-million Large Coil Test Facility, which Is designed to test superconducting magnetic coils similar to those needed to confine plasmas economically in large tokamaks, is 60% completed. Construction will be completed next year, and tests of all six coils-from U.S. industry and Japan, Switzerland, and the European Com­ munity-will begin in 1984.

T: An Updtlte

The Elmo Bumpy Torus Proof-of-Principle facility (EBT-P) is being designed and will be built by McDonnell Douglas Astronautics Company for ORNL in the Oak Ridge Valley to permit the achievement of a better operat­ In other developments in ORNL's tokamak Industrial Park. Principal subcontractors ing region. program, the pellet fueling project demon­ include General Dynamics Corporation and In the U.S. toroidal confinement program, strated thet a prototypical centrifugal injector Gilbert Associates, Inc. The device is which includes tokamaks and stellarators, a can produce 150 pellets per second and sig­ estimated to cost $86 million and is slated to part of the effort is devoted to advancing the nificantly increase the density of the ISX-8 go into operation as early as May 1985, but toroidal concept. A stellarator differs from a plasma. current budget projections leave these cost tokamak in thet it uses an external coil sys­ Studies of the effects of injecting two neu­ and schedule estimates open to question. tem to produce a helical magnetic field to tral beams of hydrogen atoms in the same EBT -P is a toroidal device having 36 contain the plasma. Because a transformer­ direction relative to the plasma current modules, each with a superconducting mag­ driven plasma current is not needed, a stel­ (co-injection) or in the opposite direction netic coil made of niobium-titanium. The mag­ larator may operate at steady state. Among (counter-injection) in ISX-8 indicate that co­ nets are designed to confine a steady-state the many types of stellarators, the torsatron injection has the advantage of inhibiting hydrogen plasma within a stainless steel has continuous helical coils carrying current accumulation of impurities in the plasma inte­ toroidal vessel. Two developmental magnetic in the same direction. ORNL theorists, rior, whereas counter-injection tends to coils for the EBT-P have already been fabri­ experimentalists, and engineers are now enhance impurity buildup. cated and successfully tested at ORNL. studying various kinds of stellarator Because the wall of a tokamak reactor ORNL research In support of EBT ..P configurations to find those which, theoreti­ will be constantly bombarded by hig~nergy includes development of gyrotrons in co­ cally, have good confinement and beta capa­ neutrons from the plasma, studies are under operation with industry and development of bilities and are also attractive from an way to determine the relative resistance of components for distributing microwave power engineering standpoint. This work was materials to neutron radiation damage, from the gyrotrons to heat the EBT plasmas. undertaken here because of OANL's recog­ including swelling and changes in mechanical The objectives of EBT-P will be to demon­ nized expertise in this area; recent encourag­ properties. OANL's Metals and Ceramics strate that EBT plasmas of intermediate ing results from Japan and West Germany Division is conducting tests on austenitic values of beta can be stably confined and have also stimulated interest in stellarators. stainless steel and ferritic steels, which are that a power-producing EBT is a viable con­ The results of the ORNL studies should candidates for the Fusion Engineering De­ cept. lead to the construction of the Advanced vice. Long-ranged-ordered alloys developed On the experimental side of the EBT pro­ Toroidal Facility (ATF-1), which will replace at OANL and vanadium alloys will also be gram, a core electron temperature of 1 keV ISX-8 in the mid-19808. An ATF configura­ investigated, and studies of the relationships (as measured by soft x-ray emission) was tion has been developed which has not between the microstructure and properties of attained by microwave heating in EBT-5, only the desirable characteristica of the materials will be continued to identify ways OANL's experimental device. Electron tem­ torsatron-type device but also modular coils. of tailoring alloys to minimize radiation­ peratures appear to rise proportionately with It is called the Symmotron (symmetric modu­ induced swelling in fusion reactors. an increase in microwave power. Radio­ lar torsatron). frequency power similar to that employed in

FALL 1982 25 short-wave radio broadcasting is being used stress. Dislocations are slippages of rows of erated at the crack tip tend to move through in ion cyclotron heating experiments to heat atoms several atomic spaces relative to the dislocation-free zone and join other dislo­ the ions of the EBT-s plasma. Results indi­ other planes of atoms. cations in the plastic zone, with the max­ cate that ion heating is obtained at high har­ One of the objectives of these studies by imum density of dislocations being near the monics of the ion cyclotron frequency. Dou­ Mike Ohr, Joe Horton, and S. Chang of the crack tip in what we call an inverse pileup. bling of beta of the electron rings (which Solid State Division is to understand why Fracture occurs by propagation of the crack help stabilize EBT plasmas) was also seen structural materials, which are normally into the dislocation-free zone, which moves at the highest levels of ion cyclotron heating. tough, fracture in a brittle manner in harsh just ahead of the growing crack. • Neither observation is understood, but theor­ environments at relatively low stresses. In Ohr and his colleagues also made the ists are currently trying to interpret these the cases of high-temperature energy sys­ interesting discovery that the dislocations effects. tems such as breeder reactors or coal move away from the crack tip as the speci­ Using laser-induced resonance fluores­ Uquefaction facilities, structural materials men is stressed and return to the crack tip cence spectroscopy, ORNL's Solid State must endure radiation or corrosive environ­ and disappear as the stress is reduced Division in collaboration with KFA ..Uiich in ments in addition to applied stresses. under cyclic loading conditions. West Germany measured the density and Structural materials such as stainless Ohr, Horton, and Chang have studied distribution function of aluminum impurities in steels are normally tough because, if any several different metals, including aluminum, EBT-S plasmas. In this technique, concen­ tiny cracks exist in the steel, the crack-tip molybdenum, copper, and tungsten. By trated light of the proper frequency is area is deformed plastically by emitting dislo­ counting the number of dislocations in front beamed from a pulsed dye laser into the cations and moving them through the of a crack in each material under stress, plasma; aluminum in the hydrogen plasma is material. That is, when the material is under they have determined the degree of difficulty excited by the laser light and then decays stress, the crack tends not to grow because in generating dislocations at the crack tip. by emitting photons. By measuring the inten­ the energy is dissipated through the move­ This critical stress intensity factor for dislo­ sity of this fluorescence, the density of ment of dislocations from the crack tip. As cation generation determines how long the aluminum was determined for distances of the dislocations move to accommodate the metal can resist cracking or breaking under between 5 and 14 em from the vessel wall. prolonged or repeated stress, the material prolonged or repeated stress. Such informa­ The technique will be applied in ISX-B and undergoes a permanent change in shape, or tion may prove useful to designers of energy EBT-s to detect and measure neutral hydro­ plastic deformation. systems, airplanes, and building structures. gen and other wall-generated impurities that Mike Ohr and his colleagues got an inside tend to cause energy losses in the plasma. look at the atomic behavior of metals when lleltlng ObHrved In they captured on videotape the movements Luer-Ann.. led Silicon Solid St.te Dlvlelon, of dislocations in a notched piece of metal Aprtl21-22 that was stretched in an electron In the late 1970s ORNL solid-state physi­ llech8nlama of lleta Fracture microscope in a tensile specimen holder cists developed the technique of laser designed by Horton. Transmission electron annealing for removing damage in silicon The tragic DC-10 crash at Chicago's microscopy at a magnification of 300,000X caused by ion implantation of dopants. They O'Hare International Airport in May 1979 shows the actual movement of dislocations used the laser-annealed, ion-implanted silicon was caused by the failure of a pylon which from the crack tip through the material. for making experimental solar-electric cells connects an engine to the airplane's wing. Observations in the electron microscope of potentially high effiCiency. Metal fatigue in bolts was believed to be show that, for each metal studied, a limited Since then, solid-state scientists have partly responsible for the collapse of the number of dislocations are generated at the been speculating about what structural and walkway at the Hyatt Regency Hotel in Kan­ crack tip in response to an externally applied phase changes may be occurring in the sas City, Missouri, during a July 1981 tea stress. The number of dislocations is an indi­ semiconductor material during the annealing dance. In each accident, more than 100 cation of the fracture toughness, or resis­ process. Two theoretical models have been people were killed. tance to cracking, of the material. proposed. One theory is that the pulses of As these incidents show, the failure of For example, copper was found to have laser light cause the crystalline surface of metal parts under prolonged stress can have 100 times as many dislocations generated the silicon to convert momentarily to a "cool devastating effects. They suggest the need as tungsten, indicating 100 times the frac­ plasma-fluid" no warmer than 400°C. The to be able to predict how long various ture toughness of tungsten-that is, it can other theory holds that the silicon surface materials can hold up under stress and to be bent or stretched much longer before melts, losing its crystalline structure tem­ understand why some metals crack under a breaking. Ohr explains that dislocations relax porarily as its temperature reaches the melt­ given stress while others do not. the stress on a material and prevent or slow ing point of 1410°C. ORNL's basic studies of the mechanisms the growth of small cracks. During 1981 ORNL solid-state physicists of metal fracture using a high-resolution elec­ What determines the extent of plastic using synchrotron x rays have shown that tron microscope have offered the first direct deformation at the crack tip? Says Ohr: laser annealing causes significant heating of experimental confirmation of the theory of "Careful examinations of the crack-tip defor­ pure silicon and induces melting in boron­ fracture proposed by British scientists B. A. mation of various metals and alloys under implanted silicon. Their findings were Bilby, A. H. Cottrell, and K. H. Swinden. One stress in an electron microscope have shown reported in the February 1, 1982, issue of dramatic result of these studies is a video that there is a zone near the crack tip which Physical Review Letters. recording that captures the movement of is devoid of dislocations. We call this area Ben Larson, Woody White, and Tom Nog­ dislocations near cracks in metals under the dislocation-free zone. Dislocations gen- gle of the Solid State Division and Dennis

26 OAK RIDGE NATIONAL LABORATORY Review Aluminum When applied stresses are removed from a metal that is starting to crack, dislocation8 100 nm (area resembling a black crook) can return to tM crack tip.

not expect to find superconductivity and fer­ romagnetism in the same material. Nevertheless, research at ORNL's High Flux Isotope Reactor and elsewhere has turned up evidence for the coexistence of superconductivity and ferromagnetism in two materials containing rare earths. Using neu­ tron diffraction and bulk resistivity measure­ ments, Herbert Mook of ORNL's Solid State Division in collaboration with David Hinks, Sunil K. Sinha, and George W. Crabtree of Argonne National Laboratory found that a 17 24 31 single crystal of erbium rhodium boride can accommodate both superconducting and fer­ romagnetic regions when cooled to a tem­ Mills of Cornell University carried out time­ the surface of the silicon had attained a non­ perature between 0. 7 and 1 K. A modulated resolved studies of silicon samples at the crystalline molten state. As the silicon cooled magnetic moment component is also found in Cornell High Energy Synchrotron Source dur­ after a laser pulse, the melted layer this temperature range. Below 0. 71 K the ing annealing by a pulsed laser (shipped by recrystallized rapidly. modulated magnetic moment disappears sud­ truck from ORNL to Cornell). Produced by a "Our synchrotron radiation studies, • says denly, with loss of superconductivity and a single "bunch" of electrons as they whirl Larson, "show that the melting model transition to a normal ferromagnetic state. around a circular racetrack every 2.5 correctly explains the effect of laser anneal­ Previous studies on powders of erbium microseconds, synchrotron x-ray beams are ing on silicon. In addition, synchrotron x rays rhodium boride at Brookhaven National 100,000 times as intense as the radiation have provided the first real-time structural Laboratory suggested that there might be a emitted from the largest x-ray tube. Because information on crystal growth at high (meters coexistence state, but the ORNL study on a the annealing of silicon occurs in 100 to 200 per second) solidification rates. And they crystal pinned down the coexistence state to nanoseconds following the firing of the laser have given us a sensitive probe of thermal a narrow temperature range and determined pulse, synchrotron radiation pulses are the expansion of the lattice as a function of the properties of the modulated component only source of x rays intense enough over a depth-below the crystal surface-during of the moment. Mook attributed the success very short time (0. 1 nanosecond) to follow the annealing process. of the ORNL study partly to the fact that laser-induced structural and phase changes. "These studies have provided fundamental Hinks was able to grow, for the first time, a In these experiments, silicon is a self­ information on the laser annealing process, • crystal of erbium rhodium boride at Argonne. thermometer; that is, its lattice expands as it Larson said. "What may even be more It is the only such crystal in existence. becomes hotter, just as mercury expands important is that this work has demonstrated Another material in which ferromagnetism and rises up a tube in a room thermometer. that diffraction measurements can be made and superconductivity may coexist is hol­ To determine the extent to which silicon in billionths of a second, thus facilitating the mium molybdenum sulfide. This discovery heats up during laser annealing, the ORNL study of fast-transient phenomena in solids.· was made at the University of Geneva in physicists measured the amount of silicon Switzerland in the early 1970s. Holmium lattice expansion by x-ray diffraction. Their Superconductivity •nd molybdenum sulfide and erbium rhodium first experiments with pure silicon showed llllgnetlsm In Cold 1118tter boride are similar in that they each contain a that, during laser annealing, it had expanded rare earth, which forms an ordered lattice of 0.75%, which indicates that it was heated to In a number of materials chilled to a few magnetic ions within the crystal, and a tran­ 1150°C before cooling. This finding casts degrees above absolute zero, one may find sition metal, which acts as a superconductor doubt on the validity of the cool-plasma one of two properties: (1) ferromagnetism, in at low temperature. theory, but it did not fully substantiate the which the electron spins are simultaneously Mook and his associates are continuing melting theory. aligned in parallel, or (2) superconductivity, their experiments to test their hypothesis When the physicists looked at laser in which electrons flow freely through a that coexistence of the superconducting and annealed, boron-implanted silicon, they found material without resistance because the elec­ ferromagnetic phases over a finite tempera­ that the silicon lattice expanded by an trons form pairs in which the spins are in ~ re range suggests the existence of "a amount consistent with the melting point tem­ antiparallel alignment. Because electron spins remarkabla new pseudophase, namely a perature of 1410°C. At one point, no are in opposing directions, these two com­ mosaic of microscopic superconductlng and scattering of x rays was observed from the peting forms of long-range order tend to ferromagnetic regions with a characteristic boron-implanted region; this indicated that annihilate each other. Therefore, one would length of 2000 A. •

FALL 1982 27 contributing editor to Communications, a publication of the American Ceramic Society, for awards and appointments a two-year period. ORNL's outstanding safety record of 15 months without a lost-time No less than six IR-100 awards Stan David has been honored with accident has earned it a succession were the ORNL harvest in this the American Welding Society's of awards. Union Carbide Corpora­ year's competition. The winners James F. Lincoln Gold Medal tion has selected the Laboratory for were: The in-core temperature, den­ Award, presented annually for a its Outstanding Safety Performance sity, and level measurement system, single-author paper published in Gold Award, the first individual developed by G. N. Miller, R. L. the society's publication, Welding UCC-operated facility to be so Anderson, and S. C. Rogers; the Journal He also served as General honored. The National Safety Coun­ inductively coupled plasma spec­ Chairman of the 1982 International cil has given its Award of Honor to trometer, developed by J. H. Conference on Welding Technology, the Laboratory for the seventh con­ Stewart Jr.; dispersed-metal­ sponsored by the American Weld­ secutive year. In addition, the NSC toughened ceramics, developed by ing Society, Northeast Tennessee cited ORNL for Best Record for Chester Morgan and Arthur Section, and the American Society Research and Development Labora­ Moorhead, shared with ORNL­ for Metals, Joining Division. tories in 1981 and awarded it first Ceramics containing metallic pre­ M. B. Herskovitz has been named place in the Chemical Section cipitates, developed by J. Narayan a fellow in the Instrument Society Safety Contest, Division 1, Group 1, and Y. Chen; GraphNOL, developed in a field of 40 major chemical of America. by Walt Eatherly and Ray Ken­ research and production facilities. nedy; ORNL-Super 9 Cr-1 Mo alloy, Among the officers elected to the developed by V. K. Sikka, R. E. Central Region Chapter of the R. E. Barker has been named McDonald, J. F. King, and Pete Institute of Nuclear Materials chairman-elect of the local chapter Patriarca; and the monazite process Management are H. C. Austin, of the American Institute of Chemi­ for stabilization of high-level chairman, and John Wachter, cal Engineers. He has also been radioactive waste, developed by treasurer. appointed to the Physical Lynn Boatner and Marvin Abra­ Properties Committee of the Susan Whatley has been nom­ ham. ASPEN Users Group. inated to the Executive Committee Walt Eatherly has been elected of the Society of Women Engineers J. R. Hightower was named chairman of Committee C-5 on for the 1982-1983 term. In this Engineer of the Year by the Manufactured Carbon and Graphite capacity she will be responsible for Knoxville-Oak Ridge Section of Products of the American Society all committees involved with the AIChE for 1982. for Testing and Materials. student sections of SWE and will be W. W. Pitt has been selected to the Executive Committee Director John Ridley, Jim Kolb, and Mike serve on the ASTM-D34 Committee for Student Affairs. Karnitz were recipients of a Certifi­ on Waste Disposal and the cate for Creative Excellence from James Barker has returned to Research and Program Committees the U.S. Industrial Film Festival ORNL to assume the responsibili­ for the Water Pollution Control for their work on the film "An ties of director of the Employee Federation. Energy Opportunity" on the subject Relations Division, replacing Joe Ray Wymer has accepted a second of district heating. Vogt. three-year appointment on the Sub­ Bob Jolley has been elected chair­ Michael Kania was selected to committee on Nuclear and man of the Division of Environmen­ receive the Borchers Medal from Radiochemistry of the Commission tal Chemistry of the American the Rhine-Westphalia Technical on Physical Sciences, Mathematics, Chemical Society for a two-year University of Aachen, Federal and Resources of the National term. Republic of Germany. Research Council in the National Elizabeth Johnson, Betty Jack Lackey has been named Academy of Sciences. Maskewitz, and Enzo Ricci have secretary of the Nuclear Division of Lorraine Abbott was named Out­ been named fellows of the Ameri­ the American Ceramic Society for standing Member of the Year by can Nuclear Society. 1982-1983. He was also appointed the Oak Ridge/Knoxville Section of

28 OAK RIDGE NATIONAL LABORATORY Review the American Nuclear Society Precious Metals Institute, its W. S. Lyon has been appointed (1981-1982). highest personal award. editor of Analytical Chemistry in Nuclear Technology, the proceedings David Bartine was awarded the Jack Cunningham was appointed of the Twenty-Fifth Conference on Certificate of Governance by the chairman of the Advisory Technical Analytical Chemistry in Energy Board of Directors of the American Awareness Council of the American Technology, Gatlinburg, October Nuclear Society. Society for Metals for one year. 6-8. R. B. Perez, Gerard de Saussure, J. H. Smith was elected a director­ Tom Row has been elected first and J. Barhen, with J. Munoz­ at-large of the American Society vice-chairman and chairman-elect Cobos and R. Q. Wright, won the for Nondestructive Testing. of the Power Division of the Best Paper Award at the 1981 David Braski placed third in American Nuclear Society. Winter Meeting of the American Category A (electron or ion beam Nuclear Society, Reactor Physics Carl Burtis has been elected to two techniques) in the 1981 Division. international panels in clinical METASERV International Metal­ chemistry. He is a new member of C. V. Dodd served on the Organiz­ lography Competition sponsored by the Commission of Automation and ing Committee for the Fifth Inter­ The Institution of Metallurgists for Clinical Chemical Technology of the national Conference on Quantitative his TEM investigation of helium International Union of Pure and Nondestructive Evaluation in the implanted in an Fe/Cr/Ni alloy. Applied Chemistry and also of the Nuclear Industry, 1982, sponsored Joseph Carpenter received a DOE Expert Panel on Instrumentation of by the American Society for Metals Letter of Commendation for his the International Federation of in cooperation with the American "outstanding performance" in Clinical Chemistry.D Nuclear Society, the American directing the Materials Project Society for Nondestructive Testing, component of the Energy Conver­ First place in the Industrial and the French Society for Nondes­ sion and Utilization Technologies Category and the Seal of Approval tructive Testing. Program. from the Professional Photographers of America went to Gerald Slaughter was elected David Fahey for his photograph chairman of the American Society David P. Edmonds was appointed entitled "Laser Inspection of Fusion for Testing and Materials­ a member of the Subgroup on American Society of Mechanical Strength in the Ferrous Alloys of Mirrors" at the Southeastern Engineers-Metal Properties Council the Boiler and Pressure Vesse! Professional Photographers' Association Exhibition of 1982. The (ASTM-ASME-MPC) Joint Commit­ Committee of the American Society tee on the Effect of Temperature on of Mechanical Engineers for a five­ photograph also was accepted for the Properties of Metals. year term. inclusion in the General Exhibit of PP A's 91st International Exposition James Weir, Jr., received a Certifi­ Barbara Walton was selected by of Professional Photography this cate of Appreciation from the Oak the Environmental Sciences Divi­ year in Las Vegas. Ridge Chapter of the American sion for its second Annual Scien­ Society for Metals. tific Achievement Award. In addi­ tion, she was chosen to be a Diplo­ Everett Bloom, H. H. Haselton, mate of the American Board of J. T. Hogan, Jim Lyon, Y-K. M. Toxicology. Peng, John Sheffield, and T. E. Shannon received DOE Certificates R. E. Dial was re-elected National of Appreciation for their contribu­ Secretary of the American Society tions to the Fusion Engineering of Certified Engineering Techni­ Device. cians. Charles Yust was elected vice­ J. A. Carter has been appointed to chairman of the Nuclear Division of a three-year term on the editorial the American Ceramic Society for board of Analytical Chemistry. 1982-1983. W. D. Shults has been elected Chain T. Liu received the Plati­ program chairman and president­ num Membership (honorary life elect of the local chapter of Sigma membership) to the International Xi. OAK RIDGE NATIONAL LABORATORY REVIEW U.S. Postage P.O. Box X, Oak Ridge, Tennessee 37830 PAID BULK RATE Oak Ridge, Tenn. Permit No.3

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A butte typical of the wilderness areas in Utah under controversy between the developers and the preservationists. See article on page 18.