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Lack of immediate effects from the 1979-80 Imperial and Victoria earthquakes on the exploited Cerro Prieto geothermal reservoir (open access)

Lack of immediate effects from the 1979-80 Imperial and Victoria earthquakes on the exploited Cerro Prieto geothermal reservoir

In 1979-1980 two large earthquakes of local magnitude (M/sub L/) greater than 6.0 occurred near the Cerro Prieto geothermal field. It has been suggested that related to these seismic events there was an abrupt temperature increase in the wells completed in the shallow (alpha) reservoir. A careful study of the geochemistry of the produced fluids, as well as a cursory reservoir engineering analysis, cannot confirm either the data or the hypothesis of a massive influx of hot water into the system related to those events. Our study shows that the cold water recharge of the alpha reservoir in response to the production-induced drawdown continued, unaffected by the two earthquakes.
Date: June 1, 1986
Creator: Truesdell, A.H. & Lippmann, M.J.
Object Type: Article
System: The UNT Digital Library
Effect of irradiation-induced defects on fusion reactor ceramics (open access)

Effect of irradiation-induced defects on fusion reactor ceramics

Structural, thermal, and electrical properties critical to performance of ceramics in a fusion environment can be profoundly altered by irradiation effects. Neutron damage may cause swelling, reduction of thermal conductivity, increase in dielectric loss, and either reduction or enhancement of strength depending on the crystal structure and defect content of the material. Absorption of ionizing energy inevitably leads to degradation of insulating properties, but these changes can be reduced by alterations in structural or compositional makeup. Assessment of the irradiation response of candidate ceramics Al/sub 2/O/sub 3/, MgAl/sub 2/O/sub 4/, SiC and Si/sub 3/N/sub 4/ shows that each may find use in advanced fusion devices. The present understanding of irradiation-induced defects in ceramics, while far from complete, nevertheless points the way to methods for developing improved materials for fusion applications.
Date: January 1, 1986
Creator: Clinard, F.W. Jr.
Object Type: Article
System: The UNT Digital Library
Steady-state and transient radionuclide transport through penetrations in nuclear waste containers (open access)

Steady-state and transient radionuclide transport through penetrations in nuclear waste containers

The transport of radionuclides through penetrations in wastes containers is analyzed. Penetrations may result from corrosion or cracks and may occur in the original container material, in degraded or corroded material, or in deposits of corrosion products. In this report we do not consider how these penetrations occur or the characteristics of expected penetrations in waste containers. We are concerned here only with the analytical formulation and solutions of equations to predict rates of mass transfer through penetrations of specified size and geometry. Expressions for the diffusive mass transfer rates through apertures are presented in Chapter 2, and numerical illustrations are presented in Chapter 3. The calculations show that mass transfer through small penetrations in thin-wall containers can be great enough that the penetrated container is no longer an effective barrier for radionuclide release. Use of this theory to calculate mass transfer through thick-wall containers is the subject of a later report. 3 refs., 9 figs.
Date: July 1, 1986
Creator: Chambre, P. L.; Lee, W. W. L.; Kim, C. L. & Pigford, T. H.
Object Type: Report
System: The UNT Digital Library
Development of superconductors for applications in high-field, high-current-density magnets for fusion research (open access)

Development of superconductors for applications in high-field, high-current-density magnets for fusion research

The development of large-bore, high-field magnets for fusion energy applications requires a system approach to both magnet and conductor design. At Lawrence Livermore National Laboratory (LLNL), the criteria used to choose superconductors include: strain tolerance, radiation tolerance, heat removal, stability, fabricability, and cost. We report on the performance of industrially produced, prototype, Ti-modified Nb/sub 3/Sn wires developed with LLNL support. Wire performance characteristics evaluated include critical current as a function of magnetic field, temperature, and applied strain. Tests were performed to determine how this performance translates to the performance of a cable-in-conduit conductor system using this wire. An alternative to Nb/sub 3/Sn superconductors is NbN, which is strain and radiation insensitive. We report preliminary efforts to produce multifilamentary NbN conductors by liquid-metal infiltration of NbN-coated, high-strength fibers. In addition, we discuss the fabrication of multifilamentary NbN conductors and their possible impact on magnet design.
Date: September 26, 1986
Creator: Summers, L. T. & Miller, J. R.
Object Type: Article
System: The UNT Digital Library
Resonance ionization mass spectrometry at Los Alamos National Laboratory (open access)

Resonance ionization mass spectrometry at Los Alamos National Laboratory

Two approaches to RIMS will be discussed here. The first is the use of continuous-wave (cw) dye lasers as the ionization source. Continuous excitation effectively matches the ionization to the evaporation of sample from a resistively heated filament, providing for efficient use of the sample. In addition, cw ionization permits pulse counting detection, necessary for the measurement of large isotope ratios on small samples. In the cases of lutetium and technetium discussed below, average ionization rates with cw ionization are much larger than with pulsed ionization. The second approach to RIMS is the use of multiphoton resonances in the pulsed laser excitation of atoms. The potential advantages derived from the use of n-photon resonances (n greater than or equal to 2) include minimal laser hardware, since the fundamental output of a single dye laser is sufficient to effect ionization in a large number of elements. The possibility also exists for Doppler-free excitation, which could be used to increase the selectivity of the ionization process. Experiments with 2 + 1 (photons to resonance plus photons to ionize) RIMS schemes for several elements will be discussed. 5 refs., 2 figs., 1 tab.
Date: January 1, 1986
Creator: Miller, C. M.; Nogar, N. S.; Apel, E. C. & Downey, S. W.
Object Type: Article
System: The UNT Digital Library
Temperature control system for liquid-fed ceramic melters (open access)

Temperature control system for liquid-fed ceramic melters

A temperature-feedback system has been developed for controlling electrical power to liquid-fed ceramic melters (LFCM). Software, written for a microcomputer-based data acquisition and process monitoring system, compares glass temperatures with a temperature setpoint and adjusts the electrical power accordingly. Included in the control algorithm are steps to reject failed thermocouples, spatially average the glass temperatures, smooth the averaged temperatures over time using a digital filter, and detect foaming in the glass. The temperature control system has proved effective during all phases of melter operation including startup, steady operation, loss of feed, and shutdown. This system replaces current, power, and resistance feedback control systems used previously in controlling the LFCM process.
Date: October 1, 1986
Creator: Westsik, J. H. Jr.
Object Type: Report
System: The UNT Digital Library
Numerical studies of gravity effects in two-phase reservoirs (open access)

Numerical studies of gravity effects in two-phase reservoirs

Numerical studies are performed to investigate the effects of localized feed zones on the pressure transients in two-phase reservoirs. It is shown that gravity effects can significantly affect the pressure transients, because of the large difference in the density of liquid water and vapor. Pressure transients for shallow and deep feed zones and the resulting fluid flow patterns are discussed.
Date: June 1, 1986
Creator: Bodvarsson, G.S. & Cox, B.L.
Object Type: Article
System: The UNT Digital Library
Conventional magnet storage rings for x-ray lithography (open access)

Conventional magnet storage rings for x-ray lithography

A first pass at the design of a conventional magnet storage ring for x-ray lithogrphy is presented. Electron beam size and power specifications are given, followed by a first pass at a lattice - a 4-fold symmetric, gradient FODO cell lattice using B = 1.6 Tesla C-magnets. (LEW)
Date: October 1, 1986
Creator: Bassetti, M.; Batchelor, K.; Galayda, J.; Halama, H.; Heese, R.; Hsieh, H. et al.
Object Type: Report
System: The UNT Digital Library
Spectroscopic analysis of low Z impurities in the Tandem Mirror Experiment-upgrade (open access)

Spectroscopic analysis of low Z impurities in the Tandem Mirror Experiment-upgrade

Two absolutely calibrated EUV instruments have been used to study the impurity characteristics in the Tandem Mirror Experiment-Upgrade (TMX-U). One instrument is a normal incidence spectrograph that measures the time histories of several impurity emission lines (300 to 1800 A) in a single shot; radial scans can be obtained on a shot-by-shot basis. The other instrument is a monochromator that measures time-resolved radial profiles of a given impurity emission line in a single shot. The common intrinsic impurities measured in TMX-U are C,N,O and Ti. It has been shown that large fractions of the oxygen and nitrogen in the plasma are associated with the neutral beams while the main source of carbon is the plasma wall. In general, the concentration of each of the impurities is low (<1%), and the power radiated by them is less than 10 kW, which is a small portion of the total input power to the plasma. The concentrations of the impurities can be reduced substantially blow discharge cleaning and titanium gettering. No significant accumulation of impurity ions in the thermal barrier region has been observed.
Date: September 1, 1986
Creator: Yu, T.L.
Object Type: Report
System: The UNT Digital Library
Low cost hydrogen/novel membrane technology for hydrogen separation from synthesis gas, Phase 1. [Polyetherimide, cellulose acetate and ethylcellulose] (open access)

Low cost hydrogen/novel membrane technology for hydrogen separation from synthesis gas, Phase 1. [Polyetherimide, cellulose acetate and ethylcellulose]

The goal of this program is to develop polymer membranes useful in the preparation of hydrogen from coal-derived synthesis gas. During this quarter the first experiment were aimed at developing high performance composite membranes for the separation of hydrogen from nitrogen and carbon monoxide. Three polymers have been selected as materials for these membranes: polyetherimide cellulose acetate and ethylcellulose. This quarter the investigators worked on polyetherimide and cellulose acetate membranes. The overall structure of these membranes is shown schematically in Figure 1. As shown, a microporous support membrane is first coated with a high flux intermediate layer then with an ultrathin permselective layer and finally, if necessary, a thin protective high flux layer. 1 fig., 4 tabs.
Date: January 1, 1986
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Atlas of atomic spectral lines of plutonium emitted by an inductively coupled plasma (open access)

Atlas of atomic spectral lines of plutonium emitted by an inductively coupled plasma

Optical emission spectra from high-purity Pu-242 were generated with a glovebox-enclosed inductively coupled plasma (ICP) source. Spectra covering the 2280 to 7008 Angstrom wavelength range are presented along with general commentary on ICP-Pu spectroscopy.
Date: September 1, 1986
Creator: Edelson, M. C.; DeKalb, E. L.; Winge, R. K. & Fassel, V. A.
Object Type: Report
System: The UNT Digital Library
Analytical model for the dynamic resistivity of electrically-exploded conductors (open access)

Analytical model for the dynamic resistivity of electrically-exploded conductors

A detailed model for the dynamic resistivity of an exploding conductor presents many difficulties. An electrically-exploded conductor undergoes significant hydrodynamic expansion as it is heated. Resistivity is a function of both the temperature and density of a conductor and realistic models for resistivity over the range of parameter space experienced by an exploding conductor are quite complex. See for example, the model of Lee and More (1984). Calculation of the hydrodynamic expansion of the conductor during and subsequent to the explosion is likewise dependent on detailed knowledge of the equation of state for the conductor in a range where few experimental data exist. A further complication is the strong magnetic field which couples the hydrodynamic expansion to the currents flowing in the expanding material. In spite of the difficulties, progress is being made on detailed modeling of fuses and exploding conductors (Lidemuth and co-workers, 1985). A simpler approach has proved to be quite useful for modeling the electrical behavior of exploding bridgewire and slapper detonators and for modeling the explosionss of large conductors exploded with large capacitor banks. In the work described here, a simple, empirical model was developed which can be expressed as a closed-form algebraic expression involving four …
Date: October 10, 1986
Creator: Lee, R. S.
Object Type: Article
System: The UNT Digital Library
Fermilab Tevatron and Pbar source status report (open access)

Fermilab Tevatron and Pbar source status report

The antiproton production cycle is enumerated, and the commissioning of the antiproton source is described, giving milestones and major obstacles. The Tevatron collider operation is described, including procedure to load the Tevatron with three bunches of protons and three bunches of antiprotons. Commissioning of the Main Ring and Tevatron for collider operation is described. Development and accelerator studies in four areas were necessary: main ring RF manipulations; controls and applications software support; Tevatron storage and low-beta squeeze sequence; and study of various beam transfers, storage steps, and sequences. Final tests are described. A long range upgrade program is presently under evaluation to accomplish these goals: luminosity increase to 5 x 10/sup 31/ cm/sup -2/sec/sup -1/, production rates up to 4 x 10/sup 11/ antiprotons/hr, and intensity increase for fixed target operation. Beam quality is to be improved by the injector and main ring upgrades, and the luminosity goal is addressed by the Collider upgrade. (LEW)
Date: August 1, 1986
Creator: Edwards, H.
Object Type: Article
System: The UNT Digital Library
Radiographic detection of 100 A thickness variations in 1-. mu. m-thick coatings applied to submillimeter-diameter laser fusion targets (open access)

Radiographic detection of 100 A thickness variations in 1-. mu. m-thick coatings applied to submillimeter-diameter laser fusion targets

We have developed x-ray radiography to measure thickness variations of coatings on laser fusion targets. Our technique is based on measuring the variation in x-ray transmission through the targets. The simplest targets are hollow glass microshells or microballoons 100 to 500 ..mu..m in diameter, that have several layers of metals or plastics, 1 to 100 ..mu..m thick. Our goal is to examine these opaque coatings for thickness variations as small as 1% or 0.1%, depending on the type of defect. Using contact radiography we have obtained the desired sensitivity for concentric and elliptical defects of 1%. This percentage corresponds to thickness variations as small as 100 A in a 1-..mu..m-thick coating. For warts and dimples, the desired sensitivity is a function of the area of the defect, and we are developing a system to detect 0.1% thickness variations that cover an area 10 ..mu..m by 10 ..mu..m. We must use computer analysis of contact radiographs to measure 1% thickness variations in either concentricity or ellipticity. Because this analysis takes so long on our minicomputer, we preselect the radiographs by looking for defects at the 10% level on a video image analysis system.
Date: January 1, 1986
Creator: Stupin, D.M.
Object Type: Article
System: The UNT Digital Library
Experiments and prospects for induction linac drivers (open access)

Experiments and prospects for induction linac drivers

In the last three years, the US program in Heavy Ion Fusion has concentrated on understanding the induction linac approach to a power-plant driver. In this method it is important that the beam current be maximized throughout the accelerator. Consequently, it is crucial to understand the space-charge limit in the AG transport system in the linac and, also, to achieve current amplification during acceleration to keep pace with the kinematical increase of this limit with energy. Experimental results on both these matters and also on the use of multiple beams (inside the same accelerating structure) will be described. A new examination of the most attractive properties of the induction linac for a fusion driver has clearly pointed to the advantage of using heavy ions with a charge-state greater than unity - perhaps q = 3 may be an optimum. This development places even greater importance on understanding space-charge limits and mechanisms for emittance growth; also, it will require a new emphasis on the development of a suitable ion source.
Date: May 1, 1986
Creator: D., Keefe
Object Type: Article
System: The UNT Digital Library
FY 1987 current fiscal year work plan (open access)

FY 1987 current fiscal year work plan

This Current Year Work Plan presents a detailed description of the activities to be performed by the Joint Integration Office during FY87. It breaks down the activities into two major work areas: Program Management and Program Analysis. Program Management is performed by the JIO by providing technical planning and guidance for the development of advanced TRU waste management capabilities. This includes equipment/facility design, engineering, construction, and operations. These functions are integrated to allow transition from interim storage to final disposition. JIO tasks include program requirements identification, long-range technical planning, budget development, program planning document preparation, task guidance, task monitoring, information gathering and task reporting to DOE, interfacing with other agencies and DOE lead programs, integrating public involvement with program efforts, and preparation of program status reports for DOE. Program Analysis is performed by the JIO to support identification and assessment of alternatives, and development of long-term TRU waste program capabilities. This work plan includes: system analyses, requirements analyses, interim and procedure development, legislative and regulatory analyses, dispatch and traffic analyses, and data bases.
Date: December 1, 1986
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Physicochemical basis of the Na-K-Ca geothermometer (open access)

Physicochemical basis of the Na-K-Ca geothermometer

Regular changes in solution composition were observed experimentally during granite reaction with dilute NaCl (+CaCl/sub 2/) solutions; these changes closely follow the empirical Na-K-Ca geothermometer relationship. Initial minerals forming the granite (quartz, plagioclase, K-feldspar, and biotite) were etched by the reactions. Alteration phases formed include calcium-zeolite at <300/sup 0/C, feldspar overgrowths at >300/sup 0/C, and minor amounts of clay and calcsilicate at all temperatures. Amphibole overgrowths were also found at 340/sup 0/C. Quartz is near saturation in all experiments, and preliminary calculations of aqueous species distributions and mineral affinities indicate that the solutions achieve super-saturation with feldspars as the temperature increase. A consistent variation attributable to pH differences was observed in the empirical geothermometer relationship for all experimental data. At 340/sup 0/C, the experimental solutions appear to have deviated slightly from the empirical Na-K-Ca relationship. Such deviations may also be found in natural systems that attain such temperatures.
Date: August 1, 1986
Creator: Janecky, D. R.; Charles, R. W.; Bayhurst, Gregory K. & Benjamin, T. M.
Object Type: Report
System: The UNT Digital Library
Convective heat transport in geothermal systems (open access)

Convective heat transport in geothermal systems

Most geothermal systems under exploitation for direct use or electrical power production are of the hydrothermal type, where heat is transferred essentially by convection in the reservoir, conduction being secondary. In geothermal systems, buoyancy effects are generally important, but often the fluid and heat flow patterns are largely controlled by geologic features (e.g., faults, fractures, continuity of layers) and location of recharge and discharge zones. During exploitation, these flow patterns can drastically change in response to pressure and temperature declines, and changes in recharge/discharge patterns. Convective circulation models of several geothermal systems, before and after start of fluid production, are described, with emphasis on different characteristics of the systems and the effects of exploitation on their evolution. Convective heat transport in geothermal fields is discussed, taking into consideration (1) major geologic features; (2) temperature-dependent rock and fluid properties; (3) fracture- versus porous-medium characteristics; (4) single- versus two-phase reservoir systems; and (5) the presence of noncondensible gases.
Date: August 1, 1986
Creator: Lippmann, M.J. & Bodvarsson, G.S.
Object Type: Article
System: The UNT Digital Library
Evaluation of the geological relationships to gas hydrate formation and stability (open access)

Evaluation of the geological relationships to gas hydrate formation and stability

Although there are many publications pertaining to gas hydrates, their formation and stability in various geological conditions are poorly known. Therefore, for the same reasons and because of the very broad scope of our research, limited amount and extremely dispersed information, the study regions are very large. Moreover, almost without exception the geological environments controlling gas hydrates formation and stability of the studied regions are very complex. The regions studied (completed and partially completed - total 17 locations) during the reporting period, particularly the Gulf of Mexico and the Middle America Trench, are the most important in this entire research project. In the past, both of these regions have been extensively studied, the presence of gas hydrates confirmed and samples recovered. In our investigation it was necessary not only to review all previous data and interpretations, but to do a thorough analysis of the basins, and a critical evaluation of an previously reported and publicly available but not published information.
Date: January 1, 1986
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Reconnaissance of intertidal and subtidal zones of Back Island, Behm Canal, Southeast Alaska (open access)

Reconnaissance of intertidal and subtidal zones of Back Island, Behm Canal, Southeast Alaska

A diver reconnaissance of the intertidal and subtidal zones of Back Island, Southeast Alaska, was performed May 20-22, 1986. The specific objectives were to catalog potentially vulnerable shellfish, other invertebrates, and plant resources, and to identify potential herring spawning sites. This effort was designed to supplement the existing ecological data base for Back Island that would be used during the National Environmental Policy Act (NEPA) documentation process. A NEPA document will be prepared that describes the site environment and assesses impacts from the proposed construction and operation of the Southeast Alaska Acoustic Measurement Facility (SEAFAC). Nine diver transects were established around Back Island. Particular attention was devoted to proposed locations for the pier and float facilities and range-operations and shore-power cable run-ups.
Date: September 1, 1986
Creator: Strand, J. A. & Young, J. S.
Object Type: Report
System: The UNT Digital Library
Gaugino masses in superstring inspired models (open access)

Gaugino masses in superstring inspired models

Contributions to the masses of the gauginos in models arising as low energy limits of superstring theories are considered.
Date: August 1, 1986
Creator: Dawson, S.
Object Type: Article
System: The UNT Digital Library
Low temperature, sulfur tolerant homogeneous catalysts for the water-gas shift reaction (open access)

Low temperature, sulfur tolerant homogeneous catalysts for the water-gas shift reaction

The purpose of this report is to update and reorganize our recent review on homogeneous catalysis of the water-gas shift reaction (WGSR) based on recent literature publications and patents. This updated version will serve as a means of selecting 10 candidate catalyst systems for use in developing effective, sulfur-tolerant, low temperature WGSR catalysts. This report discusses the variations possible in the basic chemistry associated with WGSR catalytic cycles, including basic, acidic, and neutral conditions. Then individual mechanism for specific WGSR catalyst systems are discussed. Finally, on the basis of the literature reports, a list is presented of candidate catalysts and basic systems we have chosen for study in Task 3.
Date: January 20, 1986
Creator: Laine, R. M.
Object Type: Report
System: The UNT Digital Library
Neutron star formation in theoretical supernovae. Low mass stars and white dwarfs (open access)

Neutron star formation in theoretical supernovae. Low mass stars and white dwarfs

The presupernova evolution of stars that form semi-degenerate or strongly degenerate O + Ne + Mg cores is discussed. For the 10 to 13 Msub solar stars, behavior of off-center neon flashes is crucial. The 8 to 10 m/sub solar stars do not ignite neon and eventually collapse due to electron captures. Properties of supernova explosions and neutron stars expected from these low mass progenitors are compared with the Crab nebula. The conditions for which neutron stars form from accretion-induced collapse of white dwarfs in clsoe binary systems is also examined.
Date: January 1, 1986
Creator: Nomoto, K.
Object Type: Article
System: The UNT Digital Library
Numerical models for the evaluation of geothermal systems (open access)

Numerical models for the evaluation of geothermal systems

We have carried out detailed simulations of various fields in the USA (Bada, New Mexico; Heber, California); Mexico (Cerro Prieto); Iceland (Krafla); and Kenya (Olkaria). These simulation studies have illustrated the usefulness of numerical models for the overall evaluation of geothermal systems. The methodology for modeling the behavior of geothermal systems, different approaches to geothermal reservoir modeling and how they can be applied in comprehensive evaluation work are discussed.
Date: August 1, 1986
Creator: Bodvarsson, G.S.; Pruess, K. & Lippmann, M.J.
Object Type: Article
System: The UNT Digital Library