Resource Type

Generalized emittance measurements in a beam transport line (open access)

Generalized emittance measurements in a beam transport line

Motivated by the need to commission 3 beam transport lines for the new AGS Booster project, we have developed a generalized emittance-measurement program; beam line specifics are entirely resident in data tables, not in program code. For instrumentation, the program requires one or more multi-wire profile monitors; one or multiple profiles are acquired from each monitor, corresponding to one or multiple tunes of the transport line. Emittances and Twiss parameters are calculated using generalized algorithms. The required matix descriptions of the beam optics are constructed by an on-line general beam modeling program. Design of the program, its algorithms, and initial experience with it will be described. 4 refs., 2 figs., 1 tab.
Date: January 1, 1991
Creator: Skelly, J.; Gardner, C.; Luccio, A.; Kponou, A. & Reece, K.
System: The UNT Digital Library
Indium dopant/defect complexes in lightly-doped ceria (open access)

Indium dopant/defect complexes in lightly-doped ceria

Four well-defined indium-dopant/lattice-defect complexes and the non-complexed substitutional indium dopant have been observed by perturbed angular correlation (PAC) spectroscopy in cerium oxide. PAC is a nuclear hyperfine experimental method that detects interactions between a radioactive probe nucleus and nearby atoms. The magnitude and symmetry of those interactions provide a signature for the electromagnetic fields at the probe nucleus. These fields are produced by the arrangement of charges and magnetic moments in the near environment of the probe, so they provide a means of identifying defect structures.
Date: January 1, 1991
Creator: Wang, Ruiping; Gardner, J.A. (Oregon State Univ., Corvallis, OR (United States). Dept. of Physics); Evenson, W.E. (Brigham Young Univ., Provo, UT (United States). Dept. of Physics) & Sommers, J.A. (Teledyne-Wah Chang, Albany, OR (United States))
System: The UNT Digital Library
Three-dimensional calculations of fields and loading for loop and folded waveguide ICRF antennas (open access)

Three-dimensional calculations of fields and loading for loop and folded waveguide ICRF antennas

The ANT and ORION codes have been combined and used to study the loading of various antenna geometries with simple three-dimensional (3-D) effects. Both codes use a slab model with periodic Fourier analysis for modeling the toroidal and poloidal directions. The ANT code is used to prescribe current sets in a vacuum region where the field solutions are obtained analytically of each Fourier mode and matching conditions are used at poloidal/toroidal current sheet locations. Multiple current sheets are permitted and various feeder options are available to model the radial antenna currents. Current elements maybe oriented at arbitrary angles to the static magnetic field and may be independently phased in time. The fields at the plasma surface are prescribed by an impedance matrix for each Fourier mode. The ORION code solves for the fields in the plasma region using finite difference techniques, a plasma dispersion relation that retains the lowest-order finite gyroradius effects, and all three electric field components. Results are presented for a folded waveguide mock-up and for a loop antenna design under identical plasma conditions.
Date: January 1, 1991
Creator: Carter, M. D.; Baity, F. W.; Batchelor, D. B.; Hoffman, D. J.; Jaeger, E. F.; Swain, D. W. et al.
System: The UNT Digital Library
On preferential flow and its measurement (open access)

On preferential flow and its measurement

Preferential flow is a useful generic term for describing the process whereby water movement through a porous medium follows favored routes bypassing other parts of the medium. This term does not give any indication of the pore scales involved. Sometimes macropore flow is used to describe preferential flow and this term implies that large pores of some sort are conductive. There is no consensus definition of what constitutes a macropore so one needs to carefully determine what is meant when that term is used. The main focus of this report is on the measurement and characterization of preferential flow through structured soils, however, preferred path flow also occurs in sandy soils. Fingering flow in soils, a result of wetting front instability, is a third type of preferential flow that occurs in porous media with more or less random pore arrangement. There may not be any physically defined channels in the soil to account for this type of flow. A larger scale flow described as funnel flow by Kung et al. (1990) results from profile heterogeneity. Low permeability layers or coarse lenses in a profile may restrict vertical drainage redirecting flow laterally through specific regions of the profile (like a funnel). …
Date: January 1, 1991
Creator: Luxmoore, R. J.
System: The UNT Digital Library
Proceedings of the 10th international workshop on ECR ion sources (open access)

Proceedings of the 10th international workshop on ECR ion sources

This report contains papers on the following topics: Recent Developments and Future Projects on ECR Ion Sources; Operation of the New KVI ECR Ion Source at 10 GHz; Operational Experience and Status of the INS SF-ECR Ion Source; Results of the New ECR4'' 14.5 GHz ECRIS; Preliminary Performance of the AECR; Experimental Study of the Parallel and Perpendicular Particle Losses from an ECRIS Plasma; Plasma Instability in Electron Cyclotron Resonance Heated Ion Sources; The Hyperbolic Energy Analyzer; Status of ECR Source Development; The New 10 GHz CAPRICE Source; First Operation of the Texas A M ECR Ion Source; Recent Developments of the RIKEN ECR Ion Sources; The 14 GHz CAPRICE Source; Characteristics and Potential Applications of an ORNL Microwave ECR Multicusp Plasma Ion Source; ECRIPAC: The Production and Acceleration of Multiply Charged Ions Using an ECR Plasma; ECR Source for the HHIRF Tandem Accelerator; Feasibility Studies for an ECR-Generated Plasma Stripper; Production of Ion Beams by using the ECR Plasmas Cathode; A Single Stage ECR Source for Efficient Production of Radioactive Ion Beams; The Single Staged ECR Source at the TRIUMF Isotope Separator TISOL; The Continuous Wave, Optically Pumped H{sup {minus}} Source; The H{sup +} ECR Source for the LAMPF …
Date: January 1, 1991
Creator: Meyer, F W & Kirkpatrick, M I
System: The UNT Digital Library
Fabrication of oxide dispersion strengthened ferritic clad fuel pins (open access)

Fabrication of oxide dispersion strengthened ferritic clad fuel pins

A resistance butt welding procedure was developed and qualified for joining ferritic fuel pin cladding to end caps. The cladding are INCO MA957 and PNC ODS lots 63DSA and 1DK1, ferritic stainless steels strengthened by oxide dispersion, while the end caps are HT9 a martensitic stainless steel. With adequate parameter control the weld is formed without a residual melt phase and its strength approaches that of the cladding. This welding process required a new design for fuel pin end cap and weld joint. Summaries of the development, characterization, and fabrication processes are given for these fuel pins. 13 refs., 6 figs., 1 tab.
Date: January 1, 1991
Creator: Zirker, L.R. (Argonne National Lab., Idaho Falls, ID (United States)); Bottcher, J.H. (Argonne National Lab., IL (United States)); Shikakura, S. (Power Reactor and Nuclear Fuel Development Corp., Oarai (Japan)); Tsai, C.L. (Ohio State Univ., Columbus, OH (United States). Dept. of Welding Engineering) & Hamilton, M.L. (Pacific Northwest Lab., Richland, WA (United States))
System: The UNT Digital Library
Nuclear models relevant to evaluation (open access)

Nuclear models relevant to evaluation

The widespread use of nuclear models continues in the creation of data evaluations. The reasons include extension of data evaluations to higher energies, creation of data libraries for isotopic components of natural materials, and production of evaluations for radiative target species. In these cases, experimental data are often sparse or nonexistent. As this trend continues, the nuclear models employed in evaluation work move towards more microscopically-based theoretical methods, prompted in part by the availability of increasingly powerful computational resources. Advances in nuclear models applicable to evaluation will be reviewed. These include advances in optical model theory, microscopic and phenomenological state and level density theory, unified models that consistently describe both equilibrium and nonequilibrium reaction mechanism, and improved methodologies for calculation of prompt radiation from fission. 84 refs., 8 figs.
Date: January 1, 1991
Creator: Arthur, E. D.; Chadwick, M. B.; Hale, G. M. & Young, P. G.
System: The UNT Digital Library
History of the youngest members of the Valles Rhyolite, Valles caldera, New Mexico using ESR dating method (open access)

History of the youngest members of the Valles Rhyolite, Valles caldera, New Mexico using ESR dating method

The cooling history of the Valles caldera was studied by the electron spin resonance (ESR) dating method using Al and Ti centers in quartz grains which were separated from the youngest units of the Valles Rhyolite. The ESR apparent ages are much younger than fission track ages and {sup 39}Ar- {sup 40}Ar ages. Three possibilities are suggested, the first is that the ESR ages are real, the second is that ESR method did not work for these samples, and the third is that about 10--40 ka, the signal intensity was partially reduced by a thermal event such as proposed by Harrison et al. (1986). Research on the first and second possibilities is continuing. The third possibility might explain the difference between ESR ages and those by other methods (fission track and {sup 39}Ar- {sup 40}Ar). ESR dating has produced new insights regarding the history of the Valles caldera.
Date: January 1, 1991
Creator: Ogoh, K.; Toyoda, S.; Ikeda, S.; Ikeya, M. (Osaka Univ., Toyonaka (Japan). Dept. of Physics) & Goff, F. (Los Alamos National Lab., NM (United States))
System: The UNT Digital Library
Quantification and reduction of the uncertainty in mass balance models by Monte Carlo analysis of prior data (open access)

Quantification and reduction of the uncertainty in mass balance models by Monte Carlo analysis of prior data

The general objective of this workshop is to investigate and discuss methods by which uncertainties in mass balance models for toxics in the Great Lakes may be reduced. As described by the workshop prospectus, this paper is focused on problems of reducing (and quantifying) uncertainty as they relate to in situ field observations/system response measurements for the establishment of initial conditions, boundary conditions, calibration/confirmation data sets, and model post-audit data sets.'' I have taken this description to refer not only to the evaluation of uncertainty in the field observations themselves, but also to the uncertainty associated the analyses of in situ observations as they interact in the overall modeling process. Thus, I will be concerned here with quantification and reduction of uncertainty both (1) as they may be applied to descriptions of the system that is being modeled and (2) as they may be associated with model simulations.
Date: January 1, 1991
Creator: Lesht, B.M.
System: The UNT Digital Library
Advances in downhole sampling of high temperature solutions (open access)

Advances in downhole sampling of high temperature solutions

A fluid sampler capable of sampling hot and/or deep wells has been developed at Los Alamos National Laboratory. In collaboration with Leutert Instruments, an off-the-shelf sampler design was modified to meet gas-tight and minimal chemical reactivity/contamination specifications for use in geothermal wells and deep ocean drillholes. This downhole sampler has been routinely used at temperatures up to 300{degrees}C and hole depths of greater than 5 km. We have tested this sampler in various continental wells, including Valles Caldera VC-2a and VC-2b, German KTB, Cajon Pass, and Yellowstone Y-10. Both the standard commercial and enhanced samplers have also been used to obtain samples from a range of depths in the Ocean Drilling Project's hole 504B and during recent mid-ocean ridge drilling efforts. The sampler has made it possible to collect samples at temperatures and conditions beyond the limits of other tools with the added advantage of chemical corrosion resistance.
Date: January 1, 1991
Creator: Bayhurst, Gregory K. & Janecky, D. R.
System: The UNT Digital Library
A re-evaluation of the Moyuta geothermal system, Southern Guatemala (open access)

A re-evaluation of the Moyuta geothermal system, Southern Guatemala

Chemical and isotopic data from four fumarole sites combined with prefeasibility assessments obtained in the 1970s have resulted in a re-evaluation of the Moyuta geothermal system. Moyuta consists of an east-west trending complex of Quaternary andesite/dacite domes and flows cut by north-trending faults. Areas of fumaroles, acid springs, and bicarbonate-rich thermal springs flank the north and south sides of the volcanic complex. Chloride-rich thermal springs discharge along rivers at lower elevations around the Moyuta highland. The distribution of thermal features indicates that deep reservoir fluid rises convectively near the axis of volcanism. Geochemical data suggest that there are two subsystems having temperatures of about 210{degrees}C (north flank) and 170{degrees}C (south flank). Exploration wells sited near the most northerly fumarole (Azulco) achieved temperatures of {le}113{degrees}C at 1004 m depth. We suggest the fumaroles occur above hydrothermal outflow plumes confined to vertical, fault-controlled conduits. Better drilling sites occur closer to the intersections of the north trending faults and the Quaternary volcanic axis. 21 refs., 7 figs., 2 tabs.
Date: January 1, 1991
Creator: Goff, F.; Adams, A.; Trujillo, P. E.; Counce, D.; Janik, C.; Fahlquist, L. et al.
System: The UNT Digital Library
Phase control in a two-element folded waveguide array (open access)

Phase control in a two-element folded waveguide array

A pair of folded waveguides have been used to determine the mutual coupling and to measure the field distributions for the magnetic field components for single units and for a pair. The phase difference controls the field distribution and the Fourier spectrum. 3 refs., 4 figs.
Date: January 1, 1991
Creator: Haste, G.R.
System: The UNT Digital Library
Conceptual geologic model and native state model of the Roosevelt Hot Springs hydrothermal system (open access)

Conceptual geologic model and native state model of the Roosevelt Hot Springs hydrothermal system

A conceptual geologic model of the Roosevelt Hot Springs hydrothermal system was developed by a review of the available literature. The hydrothermal system consists of a meteoric recharge area in the Mineral Mountains, fluid circulation paths to depth, a heat source, and an outflow plume. A conceptual model based on the available data can be simulated in the native state using parameters that fall within observed ranges. The model temperatures, recharge rates, and fluid travel times are sensitive to the permeability in the Mineral Mountains. The simulation results suggests the presence of a magma chamber at depth as the likely heat source. A two-dimensional study of the hydrothermal system can be used to establish boundary conditions for further study of the geothermal reservoir.
Date: January 1, 1991
Creator: Faulder, D. D.
System: The UNT Digital Library
Conceptual geologic model and native state model of the Roosevelt Hot Springs hydrothermal system (open access)

Conceptual geologic model and native state model of the Roosevelt Hot Springs hydrothermal system

A conceptual geologic model of the Roosevelt Hot Springs hydrothermal system was developed by a review of the available literature. The hydrothermal system consists of a meteoric recharge area in the Mineral Mountains, fluid circulation paths to depth, a heat source, and an outflow plume. A conceptual model based on the available data can be simulated in the native state using parameters that fall within observed ranges. The model temperatures, recharge rates, and fluid travel times are sensitive to the permeability in the Mineral Mountains. The simulation results suggests the presence of a magma chamber at depth as the likely heat source. A two-dimensional study of the hydrothermal system can be used to establish boundary conditions for further study of the geothermal reservoir. 33 refs., 9 figs.
Date: January 1, 1991
Creator: Faulder, D. D.
System: The UNT Digital Library
Nucleon Radiative Capture and the Inverse Reaction at Intermediate Energies (open access)

Nucleon Radiative Capture and the Inverse Reaction at Intermediate Energies

The processes which can lead to the radiative capture of fast nucleons include direct transitions in the nuclear potential, transitions in which coherent multipole resonances are excited, transitions by nucleons which are excited in early intranuclear collisions, bremsstrahlung from nucleon-nucleon collisions and photon evaporation'' from a thermally equilibrated nucleus. Corresponding processes occur when an energetic photon ejects fast nucleons from a nucleus. As experimental information from capture and photoreactions has become more detailed, inconsistencies and uncertainties have appeared which reflect difficulties in identifying and separating the responsible processes. This has led to more sophisticated and more complicated theoretical treatments which in turn have promoted new and more demanding experiments. 38 refs. 10 figs.
Date: January 1, 1991
Creator: Halpern, I.
System: The UNT Digital Library
Characterization and utilization of hydrotreated products produced from the Whiterocks (Utah) tar sand bitumen-derived liquid (open access)

Characterization and utilization of hydrotreated products produced from the Whiterocks (Utah) tar sand bitumen-derived liquid

The bitumen-derived liquid produced in a 4-inch diameter fluidized-bed reactor from the mined and crushed ore from the Whiterocks tar sand deposit has been hydrotreated in a fixed-bed reactor. The purpose was to determine the extent of upgrading as a function of process operating variable. A sulfided nickel-molybendum on alumina hydrodenitrogenation catalyst was used in all experiments. Moderately severe operating conditions were employed; that is, high reaction temperature (617--680 K) high reactor pressure (11.0--17.1 MPa) and low liquid feed rate (0.18--0.77 HSV); to achieve the desired reduction in heteroatom content. Detailed chemical structures of the bitumen-derived liquid feedstock and the hydrotreated total liquid products were determined by high resolution gas chromatography - mass spectrometry analyses. The compounds identified in the native bitumen included isoprenoids; bicyclic, tricycle, and tetracyclic terpenoids; steranes; hopanes; and perhydro-{beta}-carotenes. In addition, normal and branched alkanes and alkenes and partially dehydrogenated hydroaromatics were identified in the bitumen-derived liquid. The dominant pyrolysis reactions were: (1) the dealkylation of long alkyl side chains to form {alpha} - and isoolefins; and (2) the cleavage of alkyl chains linking aromatic and hydroaromatic clusters. Olefinic bonds were not observed in the hydrotreated product and monoaromatic hydrocarbons were the predominant aromatic species. The …
Date: January 1, 1991
Creator: Tsai, C. H.; Longstaff, D. C.; Deo, M. D.; Hanson, F. V. & Oblad, A. G.
System: The UNT Digital Library
National conference on integrated resource planning: Proceedings (open access)

National conference on integrated resource planning: Proceedings

Until recently, state regulators have focused most of their attention on the development of least-cost or integrated resource planning (IRP) processes for electric utilities. A number of commissions are beginning to scrutinize the planning processes of local gas distribution companies (LDCs) because of the increased control that LDCs have over their purchased gas costs (as well as the associated risks) and because of questions surrounding the role and potential of gas end-use efficiency options. Traditionally, resource planning (LDCs) has concentrated on options for purchasing and storing gas. Integrated resource planning involves the creation of a process in which supply-side and demand-side options are integrated to create a resource mix that reliably satisfies customers' short-term and long-term energy service needs at the lowest cost. As applied to gas utilities, an integrated resource plan seeks to balance cost and reliability, and should not be interpreted simply as the search for lowest commodity costs. The National Association of Regulatory Utility Commissioners' (NARUC) Energy Conservation committee asked Lawrence Berkeley Laboratory (LBL) to survey state PUCs to determine the extent to which they have undertaken least cost planning for gas utilities. The survey included the following topics: status of state PUC least-cost planning regulations and …
Date: January 1, 1991
Creator: unknown
System: The UNT Digital Library
Proceedings of the sixteenth biennial low-rank fuels symposium (open access)

Proceedings of the sixteenth biennial low-rank fuels symposium

Low-rank coals represent a major energy resource for the world. The Low-Rank Fuels Symposium, building on the traditions established by the Lignite Symposium, focuses on the key opportunities for this resource. This conference offers a forum for leaders from industry, government, and academia to gather to share current information on the opportunities represented by low-rank coals. In the United States and throughout the world, the utility industry is the primary user of low-rank coals. As such, current experiences and future opportunities for new technologies in this industry were the primary focuses of the symposium.
Date: January 1, 1991
Creator: unknown
System: The UNT Digital Library