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Pediatric nuclear medicine

Description: This symposium presented the latest techniques and approaches to the proper medical application of radionuclides in pediatrics. An expert faculty, comprised of specialists in the field of pediatric nuclear medicine, discussed the major indications as well as the advantages and potential hazards of nuclear medicine procedures compared to other diagnostic modalities. In recent years, newer radiopharmaceuticals labeled with technetium-99m and other short-lived radionuclides with relatively favorable radiation characteristics have permitted a variety of diagnostic studies that are very useful clinically and carry a substantially lower radiation burden then many comparable X-ray studies. This new battery of nuclear medicine procedures is now widely available for diagnosis and management of pediatric patients. Many recent research studies in children have yielded data concerning the effacacy of these procedures, and current recommendations will be presented by those involved in conducting such studies. Individual papers are processed separately for the Energy Data Base.
Date: January 1, 1986
Partner: UNT Libraries Government Documents Department

Proceedings of clinical SPECT (single photon emission computed tomography) symposium

Description: It has been five years since the last in-depth American College of Nuclear Physicians/Society of Nuclear Medicine Symposium on the subject of single photon emission computed tomography (SPECT) was held. Because this subject was nominated as the single most desired topic we have selected SPECT imaging as the basis for this year's program. The objectives of this symposium are to survey the progress of SPECT clinical applications that have taken place over the last five years and to provide practical and timely guidelines to users of SPECT so that this exciting imaging modality can be fully integrated into the evaluation of pathologic processes. The first half was devoted to a consideration of technical factors important in SPECT acquisition and the second half was devoted to those organ systems about which sufficient clinical SPECT imaging data are available. With respect to the technical aspect of the program we have selected the key areas which demand awareness and attention in order to make SPECT operational in clinical practice. These include selection of equipment, details of uniformity correction, utilization of phantoms for equipment acceptance and quality assurance, the major aspect of algorithms, an understanding of filtered back projection and appropriate choice of filters and an awareness of the most commonly generated artifacts and how to recognize them. With respect to the acquisition and interpretation of organ images, the faculty will present information on the major aspects of hepatic, brain, cardiac, skeletal, and immunologic imaging techniques. Individual papers are processed separately for the data base. (TEM)
Date: September 1, 1986
Partner: UNT Libraries Government Documents Department

Application of synchrotron radiation to x-ray fluorescence analysis of trace elements

Description: The development of synchrotron radiation x-ray sources has provided the means to greatly extend the capabilities of x-ray fluorescence analysis for determinations of trace element concentrations. A brief description of synchrotron radiation properties provides a background for a discussion of the improved detection limits compared to existing x-ray fluorescence techniques. Calculated detection limits for x-ray microprobes with micrometer spatial resolutions are described and compared with experimental results beginning to appear from a number of laboratories. The current activities and future plans for a dedicated x-ray microprobe beam line at the National Synchrotron Light Source (NSLS) of Brookhaven National Laboratory are presented.
Date: August 1, 1986
Creator: Gordon, B.M.; Jones, K.W. & Hanson, A.L.
Partner: UNT Libraries Government Documents Department

Micro-tomography using synchrotron radiation

Description: This paper discusses the results of recent experiments at Stanford Synchrotron Radiation Laboratory (SSRL) and Hamburger Synchrotronstrahlungslabor (HASYLAB) which were designed to explore the feasibility of using synchrotron radiation in high-resolution, computerized, critical-absorption tomography. The results demonstrate that it is possible, using absorption-edge differencing, to identify adjacent elements in the periodic table with high sensitivity. Furthermore, by using the fine structure in the absorption spectra, it is possible to distinguish between regions of different chemical states. Methods of using synchrotron radiation for high-resolution, three-dimensional chemical-state mapping in small samples are discussed.
Date: April 9, 1986
Creator: Johnson, Q.C.; Kinney, J.H.; Bonse, U.; Nichols, M.C.; Nusshardt, R. & Brase, J.M.
Partner: UNT Libraries Government Documents Department

FORPS: a FORTH-based production system and its application to a real-time robot control problem

Description: A simple yet very powerful system has been developed that merges the artificial intelligence qualities of a production system with the real-time control capabilities of FORTH. FORPS (FORTH-based Production System) offers the advantages of intelligent, rule-based control in a small package offering high speed, extensibility, and simplicity. A practical example of the system is presented in the development of an obstacle avoidance program to aid in controlling an overhead manipulator transport system. Several other potential applications to the area of control are discussed.
Date: January 1, 1986
Creator: Matheus, C.J. & Martin, H.L.
Partner: UNT Libraries Government Documents Department

Superlattice optical elements

Description: The performance of state-of-the-art Layered Synthetic Microstructures (LSM) or superlattices at x-ray energies even exceeding the soft x- ray domain is a promising sign that systems of this type may play an important role as x-ray optical elements in the energy region of interest to 6-GeV users. As will be discussed in this paper, they are particularly attractive because of their large energy bandpass compared to crystals such as Si of Ge. In fact, they have been suggested recently as elements in high throughput large bandpass x- ray monochromators tunable in the interval of 5-30 keV. For high flux applications, the hope is that LSM will prove to be stable in intense photon beams enabling them to filter out most of the heat load that will reach narrow bandpass crystal optical elements. A concurrent requirement is that their reflectivity in the x-ray region be large enough so that the gain in the bandpass will not be offset by and overall loss in flux. The effectiveness of these devices as optical elements will depend on optimization of the reflectivities of LSM through adequate design optimization modeling and fabrication techniques.
Date: March 1, 1986
Creator: Viccaro, P.J. & Ziegler, E.
Partner: UNT Libraries Government Documents Department

Applications of the MEVVA high current metal ion source

Description: A new kind of ion source has been developed in which a metal vapor vacuum arc (MEVVA) is used to produce the plasma from which the ion beam is extracted. The novel and exciting feature of this source is the very high metal ion beam current attainable. A total ion beam current of over 1 Ampere has been extracted from the embodiment of the concept that we're presently using, and this is not a limit of the method. The source was developed to upgrade the uranium ion beam intensity of the Bevatron, LBL's heavy ion synchrotron, for basic nuclear physics research. Other important applications include its use within the Heavy Ion Fusion research effort; for ion implantation; and for other basic research uses. In this paper the source is described briefly, its performance outlined, and its poential and limitations for a variety of applications is discussed.
Date: August 1, 1986
Creator: Brown, I.G.
Partner: UNT Libraries Government Documents Department

Physics of antimatter-matter reactions for interstellar propulsion

Description: At the stage of the antiproton-nucleon annihilation chain of events relevant to propulsion the annihilation produces energetic charged pions and gamma rays. If annihilation occurs in a complex nucleus, protons, neutrons, and other nuclear fragments are also produced. The charge, number, and energy of the annihilation products are such that annihilation rocket engine concepts involving relatively low specific impulse (I/sub sp/ approx. = 1000 to 2000 s) and very high I/sub sp/ (3 x 10/sup 7/ s) appear feasible and have efficiencies on the order of 50% for annihilation energy to propulsion energy conversion. At I/sub sp/'s of around 15,000 s, however, it may be that only the kinetic energy of the charged nuclear fragments can be utilized for propulsion in engines of ordinary size. An estimate of this kinetic energy was made from known pieces of experimental and theoretical information. Its value is about 10% of the annihilation energy. Control over the mean penetration depth of protons into matter prior to annihilation is necessary so that annihilation occurs in the proper region within the engine. Control is possible by varying the antiproton kinetic energy to obtain a suitable annihilation cross section. The annihilation cross section at low energies is on the order of or larger than atomic areas due to a rearrangement reaction, but it is very low at high energy where its value is closer to nuclear areas.
Date: August 22, 1986
Creator: Morgan, D.L. Jr.
Partner: UNT Libraries Government Documents Department

Fiber optics applications in hostile environments

Description: This Conference focuses on applications of optical fibers in hostile environments. As the introductory paper in this Conference, this communication will trace the evolution of applications of fibers in hostile environments and explore some of the motivations for these applications. A few key examples will be used.
Date: January 1, 1986
Creator: Lyons, P.B.
Partner: UNT Libraries Government Documents Department

Long-pulse excimer lasers for materials processing and medical applications

Description: Present day commercial excimer lasers with the exception of the Helionetics device are inherently short pulse ultraviolet sources. The pulses are short due to the inherent instability of the avalanche discharge with electronegative elements in the gas mix. The utilization of an initial fast voltage risetime allows one to overcome this difficulty and a number of long-pulse lasers are built using this technique. While the initial lasers of this form used a series rail-gap to achieve the fast voltage risetime, subsequent schemes using magnetic pulse compression and a fast prepulse have greatly improved the viability of the technique as a commercial device. Presently, however, these devices are generally rather bulky. This report discusses a passive stabilization technique that not only allows long pulse laser operation, but allows for a much slower charging circuit as well as a factor of 10 gain in pulse repetition rate per given gas flow compared with more conventional excimer laser systems. The slower charging circuit greatly eases the stress on the pulse power components such as thyratrons and capacitors and should be an important factor contributing to dependable industrial excimer laser systems. The gain of a factor of 10 in pulse repetition rate per unit gas flow results in extremely high pulse repetition rate laser systems in a very compact package; such lasers should find a place in a number of industrial and medical applications. 10 figs.
Date: January 1, 1986
Creator: Sze, R.C.
Partner: UNT Libraries Government Documents Department

Application of robotics in nuclear facilities

Description: Industrial robots and other robotic systems have been successfully applied at the Savannah River nuclear site. These applications, new robotic systems presently under development, general techniques for the employment of robots in nuclear facilities, and future systems are discussed.
Date: January 1, 1986
Creator: Byrd, J S & Fisher, J J
Partner: UNT Libraries Government Documents Department

Application of supercomputers to 3-D mantle convection

Description: Current generation vector machines are providing for the first time the computing power needed to treat planetary mantle convection in a fully three-dimensional fashion. A numerical technique known as multigrid has been implemented in spherical geometry using a hierarchy of meshes constructed from the regular icosahedron to yield a highly efficient three-dimensional compressible Eulerian finite element hydrodynamics formulation. The paper describes the numerical method and presents convection solutions for the mantles of both the earth and the Moon. In the case of the Earth, the convection pattern is characterized by upwelling in narrow circular plumes originating at the core-mantle boundary and by downwelling in sheets or slabs derived from the cold upper boundary layer. The preferred number of plumes appears to be on the order of six or seven. For the Moon, the numerical results indicate that development of a predominately L = 2 pattern in later lunar history is a plausible explanation for the present large second-degree non-hydrostatic component in the lunar figure.
Date: January 1, 1986
Creator: Baumgardner, J.R.
Partner: UNT Libraries Government Documents Department

HPRR operating experience and applications

Description: The Health Physics Research Reactor (HPRR) is a small, unmoderated fast pulse reactor located at the Oak Ridge National Laboratory (ORNL). The HPRR is the principal research tool of ORNL's Dosimetry Applications Research (DOSAR) Group. The reactor is described, its operating experience is presented, and its major applications are discussed.
Date: January 1, 1986
Creator: Bailiff, E.G.; Sims, C.S. & Swaja, R.E.
Partner: UNT Libraries Government Documents Department

Potentials for fuel cells in refineries and chlor-alkali plants

Description: The market potentials for fuel cell cogeneration systems in petroleum refineries and chlor-alkali plants were evaluated. the most promising application appears to be in chlor-alkali plants where the production process is electricity intensive. Future anticipated changes in the production process are favorable to the use of fuel cells. The energy use in refineries is steam intensive with the required steam pressures ranging from approximately 15 to 650 psig. The near-term use of fuel cell cogeneration in refineries is not as attractive as in chlor-alkali plants. The phosphoric acid fuel cell is the most developed and the most competitive, but its use is limited by its being able to produce only low-pressure steam. Over the longer term, the molten carbonate and the solid oxide fuel cell both of which operate at significantly higher temperatures, are technically very attractive. However, they do not appear to be cost competitive with conventional systems.
Date: January 1, 1986
Creator: Altseimer, J.H. & Roach, F.
Partner: UNT Libraries Government Documents Department

Some applications of AI (Artificial Intelligence) to the problems of accelerator physics

Description: Failure of orbit correction schemes to recognize betatron oscillation patterns obvious to any machine operator is a good problem with which to analyze the uses of Artificial Intelligence and the roles and relationships of operators, control systems and machines. Because such error modes are very common, their generalization could provide an efficient machine optimization and control strategy. A set of first-order, unitary transformations connecting canonical variables through measured results are defined which can either be compared to design for commissioning or to past results for 'golden orbit' operation. Because these relate directly to hardware variables, the method is simple, fast and direct. It has implications for machine design, controls, monitoring and feedback. Chronological analysis of such machine signatures can predict or provide a variety of information such as mean time to failure, failure modes and fast feedback or feedforward for optimizing figures of merit such as luminosity or current transmission. The use of theoretical and empirical scaling relations for such problems is discussed in terms of various figures of merit, the variables on which they depend as well as their functional dependences.
Date: September 1, 1986
Creator: Higo, T.; Shoaee, H. & Spencer, J.E.
Partner: UNT Libraries Government Documents Department

Space nuclear safety program. Progress report, September 1984

Description: This technical monthly report covers studies related to the use of /sup 238/PuO/sub 2/ in radioisotope power systems conducted for the Office of Special Nuclear Projects of the US Department of Energy by Los Alamos National Laboratory. Most of the studies discussed are ongoing; the results and conclusions described may change as the work progresses. 15 figs.
Date: February 1, 1986
Creator: George, T.G. (comp.)
Partner: UNT Libraries Government Documents Department

Analysis of FEL optical systems with grazing incidence mirrors

Description: The use of grazing incidence optics in resonators alleviates the problem of damage to the optical elements and permits higher powers in cavities of reasonable dimensions for a free electron laser (FEL). The design and manufacture of a grazing incidence beam expander for the Los Alamos FEL mock-up has been completed. In this paper, we describe the analysis of a bare cavity, grazing incidence optical beam expander for an FEL system. Since the existing geometrical and physical optics codes were inadequate for such an analysis, the GLAD code was modified to include global coordinates, exact conic representation, raytracing, and exact aberration features to determine the alignment sensitivities of laser resonators. A resonator cavity has been manufactured and experimentally setup in the Optical Evaluation Laboratory at Los Alamos. Calculated performance is compared with the laboratory measurements obtained so far.
Date: January 1, 1986
Creator: Knapp, C.E.; Viswanathan, V.K.; Bender, S.C.; Appert, Q.D.; Lawrence, G. & Barnard, C.
Partner: UNT Libraries Government Documents Department

Analysis of inelastic neutron scattering spectra from a time-of-flight spectrometer with filter detector

Description: Inelastic neutron scattering spectra obtained from time-of-flight spectrometers with filter detector suffer in energy resolution from a long time-of-flight tail in the filter response function. A mathematical method is described which removes this tail in measured spectra. The energy resolution can thereby be adapted for each part of the spectrum. Applications of the method to data taken at the LANSCE pulsed spallation source are presented.
Date: January 1, 1986
Creator: Vorderwisch, P.; Mezei, F.; Eckert, J. & Goldstone, J.A.
Partner: UNT Libraries Government Documents Department

Evolution of free-electron laser development

Description: Recent experimental demonstrations of free-electron laser oscillators and amplifiers have verified the feasibility of these broadly tunable photon sources. We review the current status and their continuing evolution toward ever higher output power and shorter wavelengths. 46 refs.
Date: January 1, 1986
Creator: Newman, B.E.
Partner: UNT Libraries Government Documents Department

Economic assessment of coal-burning locomotives: Topical report

Description: The General Electric Company embarked upon a study to evaluate various alternatives for the design and manufacture a coal fired locomotive considering various prime movers, but retaining the electric drive transmission. The initial study was supported by the Burlington-Northern and Norfolk-Southern railroads, and included the following alternatives: coal fired diesel locomotive; direct fired gas turbine locomotives; direct fired gas turbine locomotive with steam injection; raw coal gasifier gas turbine locomotive; and raw coal fluid bed steam turbine locomotive. All alternatives use the electric drive transmission and were selected for final evaluation. The first three would use a coal water slurry as a fuel, which must be produced by new processing plants. Therefore, use of a slurry would require a significant plant capital investment. The last two would use classified run-of-the-mine (ROM) coal with much less capital expenditure. Coal fueling stations would be required but are significantly lower in capital cost than a coal slurry plant. For any coal fired locomotive to be commercially viable, it must pass the following criteria: be technically feasible and environmentally acceptable; meet railroads' financial expectations; and offer an attractive return to the locomotive manufacturer. These three criteria are reviewed in the report.
Date: February 1, 1986
Partner: UNT Libraries Government Documents Department

Induction linacs as radiation processors

Description: Experiments at the Lawrence Livermore National Laboratory (LLNL), University of California, in conjunction with the University of California at Davis have shown induction linear accelerators (linacs) to be suitable for radiation processing of food. Here we describe how it might be possible to optimize this technology developded for the Department of Defense to serve in radiation processing. The possible advantages of accelerator-produced radiation over the use of radioisotopes include a tailor-made energy spectrum that can provide much deeper penetration and thereby better dose uniformity.
Date: April 14, 1986
Creator: Birx, D.L.
Partner: UNT Libraries Government Documents Department

Simple, compact, high brightness source for x-ray lithography and x-ray radiography

Description: A simple, compact, high brightness x-ray source has recently been built. This source utilizes a commercially available, cylindrical geometry electron beam evaporator, which has been modified to enhance the thermal cooling to the anode. Cooling is accomplished by using standard, low-conductivity laboratory water, with an inlet pressure of less than 50 psi, and a flow rate of approx.0.3 gal/min. The anode is an inverted cone geometry for efficient cooling. The x-ray source has a measured sub-millimeter spot size (FWHM). The anode has been operated at 1 KW e-beam power (10 KV, 100 ma). Higher operating levels will be investigated. A variety of different x-ray lines can be obtained by the simple interchange of anodes of different materials. Typical anodes are made from easily machined metals, or materials which are vacuum deposited onto a copper anode. Typically, a few microns of material is sufficient to stop 10 KV electrons without significantly decreasing the thermal conductivity through the anode. The small size and high brightness of this source make it useful for step and repeat exposures over several square centimeter areas, especially in a research laboratory environment. For an aluminum anode, the estimated Al-K x-ray flux at 10 cms from the source is 70 ..mu..W/cm/sup 2/.
Date: February 19, 1986
Creator: Hawryluk, A.M.
Partner: UNT Libraries Government Documents Department

New cholescintigraphic agent: ruthenium-97-DISIDA

Description: These studies demonstrate the first application of Ru-97-DISIDA in human subjects. High quality images were obtained. Scintigraphic findings in patients with hepatobiliary disorders were consistent with the biodistribution data obtained in experinmental animals and with other imaging procedures and clinical findings. Administration of Ru-97-DISIDA I.V. and of a solid test meal labeled with Tc-99m-Sulfur Colloid allowed simulateneous detection and quantification of deodenogastric reflux and determination of the gastric emptying rate. This represents an advantage as compared to the currently used techniques which necessitate two separate studies if a solid meal is used, or would mandate a liquid meal for a simultaneous study. The excellent nuclear decay characteristics of Ru-97 (tl/2 69.6 h, gamma 216 keV, 86%, no betas) permit delayed study of the hepatobiliary system with considerably less radiation exposure than I-131 Rose Bengal and with a marked improvement in image quality. 5 refs., 3 figs., 3 tabs.
Date: June 1, 1986
Creator: Zanzi, I.; Srivastava, S.C.; Meinken, G,E.; Robeson, W.; Mausner, L.F.; Fairchild, R.G. et al.
Partner: UNT Libraries Government Documents Department

Third international workshop on ice storage for cooling applications

Description: The third international workshop on ice storage for cooling applications which was informal and interactive in nature, was open to persons interested in all ice-growing technologies and in ice storage, both seasonal and diurnal. Presentations were made on some 20 topics, ranging from freezers in Alaska to ice cooling of commercial jet aircraft. Workshop tours included visits to ice-storage systems at Commonwealth Edison's facilities in Bolingbrook and Des Plaines Valley, the A.C. Neilsen builing in Northbrook, and the new State of Illinois Center in Chicago. The first workshop in the present series considered the future of ice storage and predicted applications in the agricultural sector, desalinization, and commercial ice production. Progress has been rapid in the intervening two years, and an important topic at the third workshop was the possible use of ''warm ices'' (clathrate hydrates) for energy storage. This report consists primarily of abstracts of presentations made at the workshop. Persons wishing to obtain further information about particular papers should contact the speakers directly; speakers' addresses and telephone numbers are listed in this report.
Date: April 1, 1986
Creator: Gorski, A.J. (comp.)
Partner: UNT Libraries Government Documents Department