2, Pulse-mode expansions and refractive indices in plane-wave propagation (open access)

2, Pulse-mode expansions and refractive indices in plane-wave propagation

This memo presents basic background theory for treating simultaneous propagation of electromagnetic pulses of various colors, directed along a common ray, through a molecular vapor. The memo discusses some techniques for expanding the positive frequency part of the transverse electric field into pulse modes, characterized by carrier frequencies within a modulated envelope. We discuss, in the approximation of plane waves with slowly varying envelopes, a set of uncoupled envelope equations in which a polarization mode-envelope acts as a source for an electric-field envelope. These equations, when taken with a prescription for the polarization field, are the basic equations of plane-wave pulse propagation through a molecular medium. We discuss two ways of treating dispersive media, one based upon expansions in the frequency domain and the other based in the time domain. In both cases we find envelope equations that involve group velocities. This memo represents a portion of a more extensive treatment of propagation to be presented separately. Many of the equations presented here have been described in various books and articles. They are collected and described here as a summary and review of contemporary theory.
Date: June 20, 1987
Creator: Shore, B. W.; Sacks, R.; Karr, T.; Morris, J. & Paisner, J. A.
Object Type: Report
System: The UNT Digital Library
3-D computer simulations of EM field sin the APS vacuum chamber. Part 2: Time-domain analysis (open access)

3-D computer simulations of EM field sin the APS vacuum chamber. Part 2: Time-domain analysis

Our simulations suggest that the strong peak around 4 GHz in the narrow gap observed in the measurements is generated by TE modes. Therefore, one should not worry about this peak insofar as the coupling impedance is concerned. On the other hand, some discrepancies between our simulations and the measurements are noticed and remain to be resolved.
Date: January 20, 1989
Creator: Chou, W.
Object Type: Report
System: The UNT Digital Library
Abortion, 1980-1981: Public of Opinion (open access)

Abortion, 1980-1981: Public of Opinion

This report
Date: March 20, 1981
Creator: Crocker, Royce
Object Type: Report
System: The UNT Digital Library
Acceleration of polarized protons in AHF (Advanced Hadron Facility) (open access)

Acceleration of polarized protons in AHF (Advanced Hadron Facility)

In this paper an analysis of the depolarization expected during acceleration from 0.8 to 45.0 GeV kinetic energy in the Advanced Hadron Facility (AHF) accelerators is performed.
Date: March 20, 1987
Creator: Colton, E. P.
Object Type: Article
System: The UNT Digital Library
Active Seismics to Determine Reservoir Characteristics of a Hot Dry Rock Geothermal System (open access)

Active Seismics to Determine Reservoir Characteristics of a Hot Dry Rock Geothermal System

Since 1981 three wells have been drilled to depths of between 2.0 and 2.6 km in the Carnmenellis granite, Cornwall, England in order to create a HDR geothermal system. These wells are separated by between 150 and 300 m and have been hydraulically connected by massive injections of both water and viscous gel (50 cpoise). Passive microseismic monitoring of the hydraulic stimulation and circulation experiments has been used since 1982 to determine the size and structure of the reservoir, and monitor its growth. The active seismic survey techniques of cross-hole seismics and vertical seismic profiling (VSP) have been introduced to complement the passive microseismic monitoring in characterizing the reservoir. The cross-hole seismic surveys indicate that the microseismicity defines the area of joint dilation. The attenuation of high frequencies in the region of microseismicity suggests that the reservoir is composed of a complex zone of cracks rather than a single large fracture. VSP surveys also show a good agreement between the microseismically defined reservoir and seismic signal attenuation. Recent improvements in hardware, computer processing and interpretation indicate that active seismics will play an increasingly important part in mapping and understanding geothermal reservoirs. 11 figs., 10 refs.
Date: January 20, 1987
Creator: Green, A.S.P. & Baria, R.
Object Type: Article
System: The UNT Digital Library
Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program: Topical report I, selection of candidate alloys. Volume 3. Selection of surface coating/substrate systems for screening creep and structural stability studies (open access)

Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program: Topical report I, selection of candidate alloys. Volume 3. Selection of surface coating/substrate systems for screening creep and structural stability studies

Considering the high temperature, low O/sub 2/, high C environment of operation in the Very High Temperature Reactor (VHTR) Systems, the utilization of coatings is envisaged to hold potential for extending component lifetimes through the formation of stable and continuous oxide films with enhanced resistance to C diffusion. A survey of the current state of technology for high temperature coatings has been performed. The usefulness of these coatings on the Mo, Ni, and Fe base alloys is discussed. Specifically, no coating substitute was identified for TZM other than the well known W-3 (pack silicide) and Al/sub 2/O/sub 3/ forming coatings were recommended for the Fe and Ni base structural materials. Recommendations as to coating types and processng have been made based on the predicted VHTR component size, shape, base metal and operational environment. Four tests designed to evaluate the effects of selected combinations of coatings and substrate matrices are recommended for consideration.
Date: June 20, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advanced Selenide Thermoelectric Development Program. Final Report (open access)

Advanced Selenide Thermoelectric Development Program. Final Report

The primary objective of this work was to demonstrate that copper silver selenide and TAGS could be segmented. The hot junction temperature was planned to be 725/sup 0/C with the segmentation temperature at 400/sup 0/C, both temperatures were selected to prevent excessive sublimation from the hot ends of the segments, respectively. The program was planned as a cooperative effort between General Atomic company and Teledyne Energy Systems. Accordingly, General Atomic synthesized the CuAgSe that was used to fabricate the test hardware that was ultimately delivered to General Atomic for testing. Both the CuAgSe and TAGS were hot pressed in an argon atmosphere then the segments were furnace-bonded to each other. A secondary objective was to produce CuAgSe powder by rapid solidification.
Date: July 20, 1981
Creator: Seetoo, W. R.
Object Type: Report
System: The UNT Digital Library
Advances in Tandem Mirror fusion power reactors (open access)

Advances in Tandem Mirror fusion power reactors

The Tandem Mirror exhibits several distinctive features which make the reactor embodiment of the principle very attractive: Simple low-technology linear central cell; steady-state operation; high-..beta.. operation; no driven current or disruptions; divertorless operation; direction conversion of end-loss power; low-surface heat loads; and advanced fusion fuel capability. In this paper, we examine these features in connection with two tandem mirror reactor designs, MARS and MINIMARS, and several advanced reactor concepts including the wall-stabilized reactor and the field-reversed mirror. With a novel compact end plug scheme employing octopole stabilization, MINIMARS is expressly designed for short construction times, factory-built modules, and a small (600 MWe) but economic reactor size. We have also configured the design for low radioactive afterheat and inherent/passive safety under LOCA/LOFA conditions, thereby obviating the need for expensive engineered safety systems. In contrast to the complex and expensive double-quadrupole end-cell of the MARS reactor, the compact octopole end-cell of MINIMARS enables ignition to be achieved with much shorter central cell lengths and considerably improves the economy of scale for small (approx.250 to 600 MWe) tandem mirror reactors. Finally, we examine the prospects for realizing the ultimate potential of the tandem mirror with regard to both innovative configurations and novel neutron …
Date: May 20, 1986
Creator: Perkins, L. J. & Logan, B. G.
Object Type: Article
System: The UNT Digital Library
Advective-diffusive/dispersive transport of chemically reacting species in hydrothermal systems. Final report, FY83-85 (open access)

Advective-diffusive/dispersive transport of chemically reacting species in hydrothermal systems. Final report, FY83-85

A general formulation of multi-phase fluid flow coupled to chemical reactions was developed based on a continuum description of porous media. A preliminary version of the computer code MCCTM was constructed which implemented the general equations for a single phase fluid. The computer code MCCTM incorporates mass transport by advection-diffusion/dispersion in a one-dimensional porous medium coupled to reversible and irreversible, homogeneous and heterogeneous chemical reactions. These reactions include aqueous complexing, oxidation/reduction reactions, ion exchange, and hydrolysis reactions of stoichiometric minerals. The code MCCTM uses a fully implicit finite difference algorithm. The code was tested against analytical calculations. Applications of the code included investigation of the propagation of sharp chemical reaction fronts, metasomatic alteration of microcline at elevated temperatures and pressures, and ion-exchange in a porous column. Finally numerical calculations describing fluid flow in crystalline rock in the presence of a temperature gradient were compared with experimental results for quartzite.
Date: June 20, 1986
Creator: Lichtner, P. C. & Helgeson, H. C.
Object Type: Report
System: The UNT Digital Library
AGS-Booster Orbit and Resonance Correction (open access)

AGS-Booster Orbit and Resonance Correction

None
Date: March 20, 1989
Creator: Milutinovic, J.; Ruggiero, A. G.; Tepikian, S. & Weng, W. T.
Object Type: Report
System: The UNT Digital Library
Alpha-particle-driven instability of alfven waves in a tandem mirror. Final summary report, 21 February-20 May 1985 (open access)

Alpha-particle-driven instability of alfven waves in a tandem mirror. Final summary report, 21 February-20 May 1985

Alpha particles born at D-T fusion are mirror confined in the tandem mirror due to their relatively high energy. Therefore, they have a loss-cone type distribution in the velocity space. This anisotropy is susceptible to microinstability. The objective of this work is to study the possible instability that can be driven by the alpha loss-cone. The low frequency (at the order of the ion cyclotron frequency) wave spectrum is studied to seek the waves that can be destabilized by the alphas. The radial mode structure is found for the growth rate calculation. The alpha particle distribution with a loss-cone is obtained from a Legendre function expansion and a diffusion front method. The growth rate of the instability is formulated from linear stability theory and computed numerically. A marginal stability boundary in the ion density and temperature parameters is calculated.
Date: August 20, 1985
Creator: Ho, S. K.
Object Type: Report
System: The UNT Digital Library
Alternative connections for the large MFTF-B solenoids (open access)

Alternative connections for the large MFTF-B solenoids

The MFTF-B central-cell solenoids are a set of twelve closely coupled, large superconducting magnets with similar but not exactly equal currents. Alternative methods of connecting them to their power supplies and dump resistors are investigated. The circuits are evaluated for operating conditions and fault conditions. The factors considered are the voltage to ground during a dump, short circuits, open circuits, quenches, and failure of the protection system to detect a quench. Of particular interest are the current induced in coils that remain superconducting when one or more coils quench. The alternative connections include separate power supplies, combined power supplies, individual dump resistors, series dump resistors and combinations of these. A new circuit that contains coupling resistors is proposed. The coupling resistors do not affect normal fast dumps but reduce the peak induced currents while also reducing the energy rating of the dump resistors. Another novel circuit, the series circuit with diodes, is discussed in detail.
Date: May 20, 1983
Creator: Owen, E. W.; Shimer, D. W. & Wang, S. T.
Object Type: Report
System: The UNT Digital Library
Amorphous thin films for solar-cell applications. Technical progress report, 11 October 1980 to 15 January 1981 (open access)

Amorphous thin films for solar-cell applications. Technical progress report, 11 October 1980 to 15 January 1981

Progress has been ahead of planned expectations in three instances: (a) achievement of 4 mA/cm/sup 2/, short circuit current density in a MIS structure solar cell under AM1 illumination; (b) fabrication of large area (4 cm/sup 2/) MIS cells with external J/sub sc/ > 3 mA/cm/sup 2/; and (c) deposition of p/sup +/ layers by B/sub 2/H/sub 6/ gas phase doping. A program status table is included. Reproducible n layers are now routinely deposited by sputtering in Ar, H/sub 2/, and PH/sub 3/ gases. The major remaining obstacle to the goal of a 3.5% cell is the deposition of a quality i-layer. Although information deduced from infrared absorption and Raman data indicates that most of the hydrogen is bonded in the SiH configuration, the photoconductivity of the intrinsic material requires marked improvement. Two forms of magnetron sputtering, planar and cylindrical, are being exploited. The planar deposition system has the advantage that experimental costs are low; the cylindrical system is easily scalable to large product throughput. Schematic illustrations of the two systems and descriptions of apparatus modifications incorporated are included.
Date: February 20, 1981
Creator: Jonath, A. D.; Anderson, W. W.; Crowley, J. L.; MacMillan H. F., Jr. & Thornton, J. A.
Object Type: Report
System: The UNT Digital Library
Analysis of Injection-Backflow Tracer Tests in Fractured Geothermal Reservoirs (open access)

Analysis of Injection-Backflow Tracer Tests in Fractured Geothermal Reservoirs

Tracer tests have been an important technique for determining the flow and reservoir characteristics in various rock matrix systems. While the interwell tracer tests are aimed at the characterization of the regions between the wells, single-well injection-backflow tracer tests may be useful tools of preliminary evaluation, before implementing long term interwell tracer tests. This work is concerned with the quantitative evaluation of the tracer return profiles obtained from single well injection-backflow tracer tests. First, two mathematical models of tracer transport through fractures, have been reviewed. These two models are based on two different principles: Taylor Dispersion along the fracture and simultaneous diffusion in and out of the adjacent matrix. Then the governing equations for the transport during the injection-backflow tests have been solved. Finally the results were applied to field data obtained from Raft River and East Mesa geothermal fields. In order to determine the values of the parameters of the models that define the transport mechanisms through fractures a non-linear optimization technique was employed. 26 refs., 10 figs.
Date: January 20, 1987
Creator: Kocabas, I. & Horne, R.N.
Object Type: Article
System: The UNT Digital Library
Analysis of quench-vent pressures for present design of ITER (International Thermonuclear Experimental Reactor) TF (toroidal field) coils (open access)

Analysis of quench-vent pressures for present design of ITER (International Thermonuclear Experimental Reactor) TF (toroidal field) coils

The International Thermonuclear Experimental Reactor (ITER) is a new tokamak design project with joint participation from Japan, the European Community, the Union of the Soviet Union, and the United States. This paper examines the effects of a quench within the toroidal field (TF) coils based on current ITER design. It is a preliminary, rough analysis. Its intent is to assist ITER designers while more accurate computer codes are being developed and to provide a check against these more rigorous solutions. Rigorous solutions to the quench problem are very complex involving three- dimensional heat transfer, extreme changes in heat capacities and copper resistivity, and varying flow dynamics within the conductors. This analysis addresses all these factors in an approximate way. The result is much less accurate than a rigorous analysis. Results here could be in error as much as 30 to 40 percent. However, it is believed that this paper can still be very useful to the coil designer. Coil pressures and temperatures vs time into a quench are presented. Rate of helium vent, energy deposition in the coil, and depletion of magnetic stored energy are also presented. Peak pressures are high (about 43 MPa). This is due to the very …
Date: September 20, 1989
Creator: Slack, D.S.
Object Type: Article
System: The UNT Digital Library
Analysis of the impact of decentralized solar technology on electric utilities: comparison and synthesis of models. Progress report (open access)

Analysis of the impact of decentralized solar technology on electric utilities: comparison and synthesis of models. Progress report

The validation of the physical submodels of three solar-electric utility interface models is described. The validation problem is divided into two components, the accuracy of the submodels themselves and the accuracy of the data typically used to run these models. The data set required to study these problems with respect to utility requirements is discussed and its collection in the Philadelphia Metropolitan area described. The instrumentation employed in the gathering of the data is covered. Error statistics of data and submodel accuracy are presented and the current status of the study is presented.
Date: November 20, 1980
Creator: Feldman, S. & Blair, P.
Object Type: Report
System: The UNT Digital Library
Analysis of the obstacles to financing geothermal hydrothermal commercialization projects and the government programs designed to remove them (open access)

Analysis of the obstacles to financing geothermal hydrothermal commercialization projects and the government programs designed to remove them

The risks associated with geothermal hydrothermal commercialization are broken down into five categories: resource risk; technological risk; regulatory risk; investment parity risks; and institutional risk aversion. The impact of each risk upon geothermal financing is assessed. The federal government's programs to provide financial incentives for geothermal development are presented as follows: tax incentives; indirect financial incentives programs; direct grant/cost-sharing programs; and attempts at reducing regulatory risk through the enactment of legal and institutional reforms. (MHR)
Date: March 20, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Analysis of Thermally Induced Permeability Enhancement in Geothermal Injection Wells (open access)

Analysis of Thermally Induced Permeability Enhancement in Geothermal Injection Wells

Reinjection of spent geothermal brine is a common means of disposing of geothermal effluents and maintaining reservoir pressures. Contrary to the predictions of two-fluid models (two-viscosity) of nonisothermal injection, an increase of injectivity, with continued injection, is often observed. Injectivity enhancement and thermally-affected pressure transients are particularly apparent in short-term injection tests at the Los Azufres Geothermal Field, Mexico. During an injection test, it is not uncommon to observe that after an initial pressure increase, the pressure decreases with time. As this typically occurs far below the pressure at which hydraulic fracturing is expected, some other mechanism for increasing the near-bore permeability must explain the observed behavior. This paper focuses on calculating the magnitude of the near-bore permeability changes observed in several nonisothermal injection tests conducted at the Los Azufres Geothermal Field. In order to evaluate the pressure transient data and calculate the magnitude of the thermally induced permeability changes, a new analytic solution for calculating pressure transients with time-varying sandface flowrates and temperatures has been developed. The effects of temperature-dependent fluid and rock properties, as well as a moving thermal front, are explicitly included in the calculations. Based on this new solution, a technique is developed for calculating the …
Date: January 20, 1987
Creator: Benson, S. M.; Daggett, J. S.; Iglesias, E.; Arellano, V. & Ortiz-Ramirez, J.
Object Type: Article
System: The UNT Digital Library
Analysis of Transient Pressure Tests for Olkaria Exploration Wells (open access)

Analysis of Transient Pressure Tests for Olkaria Exploration Wells

Analysis of transient pressure tests for Olkaria West wells shows that both infinite acting and double porosity models can be used to analyze the well behaviour and infer reservoir properties from fall-off steps of long enough duration, in wells where no significant thermal recovery occurs. The double porosity model gives better estimates of reservoir properties than the infinite acting model, for long fall-off steps in wells intercepting fractures. Semilog methods give fairly good estimates of reservoir transmissivity for the long fall-off steps but are highly inaccurate when used independently, especially for the short fall-off steps conducted in most of the wells. Double porosity models can also be used for recovery test analyses where two phase transients are not significant. 6 refs., 11 figs., 8 tabs.
Date: January 20, 1987
Creator: Haukwa, Charles B.
Object Type: Article
System: The UNT Digital Library
Angular distributions of target fragments from the reactions of 292 MeV - 25. 2 GeV /sup 12/C with /sup 197/Au and /sup 238/U (open access)

Angular distributions of target fragments from the reactions of 292 MeV - 25. 2 GeV /sup 12/C with /sup 197/Au and /sup 238/U

Angular distributions of target fragments from the reactions of /sup 12/C with /sup 197/Au and /sup 238/U were measured at projectile energies of 292 MeV, 1.0 GeV, 3.0 GeV, 12.0 GeV and 25.2 GeV. The angular distributions of the /sup 197/Au target fragments were all forwardly peaked. Extensively forward peaked angular distributions were observed at the non-relativistic projectile energies (292 MeV, 1.0 GeV). No obvious differences were observed in the angular distributions at the different relativistic projectile energies of 3.0 GeV, 12.0 GeV and 25.2 GeV. The characteristic angular distribution pattern from the relativistic projectile energy experiments was also observed in the non-relativistic energy experiments. Maximum degree of forward-peaking in the angular distributions at each projectile energy was observed at the product mass number (A) around 190 from the 292 MeV projectile energy, at A=180 from 1.0 GeV and at A=175 from 3.0 GeV and 12.0 GeV. In general, two different types of angular distributions were observed in the relativistic projectile energy experiments with the /sup 238/U target. Isotropic angular distributions were observed for the fission product nuclides. The angular distributions of the fission products at the intermediate (292 MeV) energy showed slightly forward- peaked angular distributions. Because of the …
Date: May 20, 1983
Creator: Morita, Y.
Object Type: Report
System: The UNT Digital Library
Anomalous isotopic composition of cosmic rays (open access)

Anomalous isotopic composition of cosmic rays

Recent measurements of nonsolar isotopic patterns for the elements neon and (perhaps) magnesium in cosmic rays are interpreted within current models of stellar nucleosynthesis. One possible explanation is that the stars currently responsible for cosmic-ray synthesis in the Galaxy are typically super-metal-rich by a factor of two to three. Other possibilities include the selective acceleration of certain zones or masses of supernovas or the enhancement of /sup 22/Ne in the interstellar medium by mass loss from red giant stars and planetary nebulas. Measurements of critical isotopic ratios are suggested to aid in distinguishing among the various possibilities. Some of these explanations place significant constraints on the fraction of cosmic ray nuclei that must be fresh supernova debris and the masses of the supernovas involved. 1 figure, 3 tables.
Date: June 20, 1980
Creator: Woosley, S. E. & Weaver, T. A.
Object Type: Article
System: The UNT Digital Library
Application of FRAMIS to K/sub D/ data (open access)

Application of FRAMIS to K/sub D/ data

This report documents an application of the FRAMIS relational data base management system. A geochemical data base of ion exchange distribution coefficients (K/sub D/) is created and maintained by using very simple commands. Reports are automatically generated. Familiarity with the LLL Octopus Time-Sharing System and FRAMIS is assumed.
Date: March 20, 1980
Creator: Storch, N.
Object Type: Report
System: The UNT Digital Library
Application of Weibull Criterion to failure prediction in compsites (open access)

Application of Weibull Criterion to failure prediction in compsites

Fiber-reinforced composite materials are being widely used in engineered structures. This report examines how the general form of the Weibull Criterion, including the evaluation of the parameters and the scaling of the parameter values, can be used for the prediction of component failure.
Date: April 20, 1981
Creator: Cain, W. D. & Knight, Jr., C. E.
Object Type: Report
System: The UNT Digital Library
Applying Flowrate Type Curves to Geysers Steam Wells (open access)

Applying Flowrate Type Curves to Geysers Steam Wells

Dimensionless flowrate type curves were applied to steam wells at The Geysers in an attempt to quantify reservoir properties and to predict flowrate decline. Although data scatter was a problem, the flowrate data was smoothed by a normalization routine based on the back-pressure equation and the wells were modeled by dimensionless functions for a radial system with a infinite or finite outer boundary and a constant pressure inner boundary (composite analytical-empirical type curve). The “match” resulted in a unique D{sub i} value for use in Arps’ equation and a permeability-thickness product (kh) comparable to kh values obtained from pressure buildup analysis. Finally, it was shown that at least four years of data is required to obtain a unique b value. 2 tabs., 12 refs., 12 figs.
Date: January 20, 1987
Creator: Enedy, Steve
Object Type: Article
System: The UNT Digital Library