Resource Type

Application of microfabrication technology to thermionic energy conversion. Progress report 4, 1 May 1980 to 31 July 1980 (open access)

Application of microfabrication technology to thermionic energy conversion. Progress report 4, 1 May 1980 to 31 July 1980

Two applications of microfabrication technology to thermionic converters have been investigated theoretically. The first is a novel method of maintaining micron or submicron spacings over large areas (>1 cm/sup 2/), using metals of different expansion coefficients to eliminate the shear stresses on the insulating pillars separating the electrodes. The second uses low-voltage field-emission sources to create ions in a large (approx. 1 mm) interelectrode gap for space charge neutralization. The theoretical results for both these approaches are highly encouraging.
Date: September 5, 1980
Creator: Brodie, I.
System: The UNT Digital Library
A Search for New Leptons with Heavy Neutrinos in e/sup +/e/sup -/ Annihilation at. sqrt. s = 29 GeV. [None] (open access)

A Search for New Leptons with Heavy Neutrinos in e/sup +/e/sup -/ Annihilation at. sqrt. s = 29 GeV. [None]

This thesis describes the results of a search for new leptons with associated heavy neutrinos. The search uses 68.1 pb/sup /minus/1/ of data taken with the TPC2..gamma.. detector at the PEP storage ring. New lepton pairs with charged lepton masses m/sub L/ < 12 GeV and mass differences in the approximate range 0.4 GeV < m/sub L/ /minus/ m/sub/nu/L/ < 2.5 GeV are excluded at the 99% confidence level. Results are also given of a study of search techniques for the region m/sub L/ < 12 GeV, m/sub L/ /minus/ m/sub ..nu..L/ < 0.4 GeV.
Date: May 5, 1988
Creator: Mathis, L. G.
System: The UNT Digital Library
Physical characterization of magmatic liquids. [Ultrasonic and Brillouin Scattering Studies of Natural and Synthetic Silicates and Oxides] (open access)

Physical characterization of magmatic liquids. [Ultrasonic and Brillouin Scattering Studies of Natural and Synthetic Silicates and Oxides]

This report describes a research project that was conducted from August 15, 1985 to February 28, 1992. The project was based on the ultrasonic studies of natural and synthetic silicate melts, and the study of Brillouin scattering of synthetic silicates and oxides. Measurements of the compressional wave velocity and attenuation can be established using the ultrasonic methods. Temperature dependences of silicates can be established by the Brillouin scattering. (MB)
Date: June 5, 1992
Creator: Manghnani, M.H.
System: The UNT Digital Library
Development and testing of shingle-type solar cell modules. Quarterly report No. 2 (open access)

Development and testing of shingle-type solar cell modules. Quarterly report No. 2

The details of a shingle module design which produces in excess of 97 watts/m/sup 2/ of module area at 1 kW/m/sup 2/ insolation and at 60/sup 0/C are reported. This selected design employs a tempered glass coverplate to provide the primary solar cell structural support. The use of the B.F. Goodrich FLEXSEAL roofing system as the outer skin of the shingle substrate provides a high confidence of achieving the 15 year service life goal. The fabrication and testing of a preproduction module of this design has demonstrated that this selected approach will meet the environmental testing requirements imposed by the contract. Attempts to fabricate a preproduction module of an alternative design, which embeds the solar cell assembly within a methyl methacrylate casting, proved unsuccessful.
Date: January 5, 1978
Creator: Shepard, N.F.
System: The UNT Digital Library
H4LM Graphite (open access)

H4LM Graphite

A commercial graphite useful in nuclear reactor construction is described. A survey of all currently available sources on chemical and physical properties was made and the information listed. Some data on cost and available sizes are also included. (auth)
Date: July 5, 1962
Creator: Merryman, R. G.; Wagner, P. & MacMillan, D. P.
System: The UNT Digital Library
High beta and second stability region transport and stability analysis (open access)

High beta and second stability region transport and stability analysis

This document describes ideal and resistive MHD studies of high-beta plasmas and of the second stability region. Significant progress is reported on the resistive stability properties of high beta poloidal supershot'' discharges. For these studies initial profiles were taken from the TRANSP code which is used extensively to analyze experimental data. When an ad hoc method of removing the finite pressure stabilization of tearing modes is implemented it is shown that there is substantial agreement between MHD stability computation and experiment. In particular, the mode structures observed experimentally are consistent with the predictions of the resistive MHD model. We also report on resistive stability near the transition to the second region in TFTR. Tearing modes associated with a nearby infernal mode may explain the increase in MHD activity seen in high beta supershots and which impede the realization of Q{approximately}1. We also report on a collaborative study with PPPL involving sawtooth stabilization with ICRF.
Date: September 5, 1991
Creator: unknown
System: The UNT Digital Library
Literature review of the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on OTEC heat exchangers (open access)

Literature review of the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on OTEC heat exchangers

An investigation of available data on the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on Ocean Thermal Energy Conversion (OTEC) heat exchangers has been carried out. Pertinent oceanographic data is lacking at or near potential OTEC sites for the calculation of the degree of saturation of seawater with respect to calcium carbonate. Consequently, only ''extrapolated'' saturation values can be used. These indicate that near surface seawater is probably supersaturated, with respect to the calcium carbonate phases calcite and aragonite, at all potential OTEC sites. The deep seawater that would be brought to the surface at the potential Atlantic Ocean sites is also likely to be supersaturated with respect to calcium carbonate. The deep seawater at the potential Pacific Ocean sites may be slightly undersaturated. The fact that OTEC heat exchangers will be operating in seawater, which is supersaturated with respect to calcium carbonate, means that if nucleation of calcite or aragonite occurs on the heat exchanger surfaces, significant growth rates of calcium carbonate scale may be expected. The potential for calcium carbonate nucleation is highest at cathodic metal surface locations, which are produced as the result of aluminum corrosion in seawater. …
Date: April 5, 1978
Creator: Morse, J. W.; de Kanel, J. & Craig, Jr., H. L.
System: The UNT Digital Library
Detection and measurement of Post-Rosenbluth convective instability in MFTF with a hybrid CO/sub 2/ laser--heterodyne diagnostic system (open access)

Detection and measurement of Post-Rosenbluth convective instability in MFTF with a hybrid CO/sub 2/ laser--heterodyne diagnostic system

To measure and classify the Post-Rosenbluth convective loss-cone instability in MFTF, we propose to use a CO/sub 2/ laser consisting of a TEA-pulsed section and a low pressure CW section, together with a light mixing receiver. Calculations show that this system offers sufficient power and sensitivity to detect instability throughout the range from strong coherent light scattering to weak incoherent scattering when the instability is eliminated.
Date: October 5, 1977
Creator: Peratt, A.L.
System: The UNT Digital Library
Shawnee test program: TVA Shawnee Test Facility. Technical progress report, April 6-May 6, 1981 (open access)

Shawnee test program: TVA Shawnee Test Facility. Technical progress report, April 6-May 6, 1981

The test obtective for April was to evaluate sodium thiosulfate in limestone scrubber slurry as inhibitor of sulfite oxidation. The resulting effect on saturation levels of calcium sulfate (CaSO/sub 4/.2 H/sub 2/O; gypsum) and scaling in the system was of prime importance. As an antioxidant, S/sub 2/O/sub 3//sup =/ functions as a scale inhibitor by reducing SO/sub 4//sup =/, a known scale former. To meet the test objective, the scrubber was operated in a scaling mode as a base case; finally, the changes resulting from addition of sodium thiosulfate were evaluated. Train 100 was operated at two pH levels and with low and high sulfur coal in April. Because of several delays explained below, only base cases were completed in April.
Date: November 5, 1981
Creator: unknown
System: The UNT Digital Library
In-Home Performance of Exempt Pellet Stoves in Medford, Oregon. (open access)

In-Home Performance of Exempt Pellet Stoves in Medford, Oregon.

Pellet stoves that are considered exempt'' operate at an air-to-fuel ratio in excess of 35:1. They therefore qualify for exemption from the emissions certification process. A primary goal of this project was to determine how a sample of such stoves, operated in homes, would perform compared to their certified cousins,'' which were evaluated the previous year. In-home performance data documenting emissions from exempt stoves and net delivered efficiencies was particularly desired. This project evaluated six pellet stoves representing three major brands in Medford, Oregon. There were three Breckwell model P24FS, one Horizon Eclipse, one Horizon Destiny, and one Earth Stove TP40. The stoves were monitored for four week-long intervals in January and February 1991, for a total of 24 tests. Evaluations were conducted for particulate, CO (carbon monoxide) and PAH (polycyclic aromatic hydrocarbon) emissions and net efficiency. Monitoring was conducted using the AWES (automated woodstove emissions sampler) sampling system. A new data logger, developed for this project, was used to control the AWES and record real time data. 22 refs., 17 figs., 6 tabs.
Date: July 5, 1991
Creator: Barnett, Stockton G. & Fields, Paula G.
System: The UNT Digital Library
Preliminary examination of the Linear Free-Electron Laser (open access)

Preliminary examination of the Linear Free-Electron Laser

The Linear Free Electron Laser is numerically analyzed in the one dimensional limit by following an average (resonant) particle. Several different wiggler schemes are presented, and electron beam current density requirements are discussed. A variable phase angle buncher is also proposed.
Date: February 5, 1979
Creator: Prosnitz, D. & Szoke, A.
System: The UNT Digital Library
Chief financial officer's task force on rationing feasibility, cost and schedule. Final report (open access)

Chief financial officer's task force on rationing feasibility, cost and schedule. Final report

The purpose of this memorandum is to report our realistic assessment of the feasibility, cost, and time frame for bringing a rationing program to 90-day readiness. The basic aspects of the nature of the rationing plan are discussed. The plan has been changed in several respects in response to comments from the Congress, the general public and the ECC, since the previous version was rejected by the Congress in May 1979. Three changes in particular impact the preimplementation process: The range of entities accorded status as priority firms has increased to cover such groups as telecommunications firms and for-hire delivery firms; All firms (not just priority users) are alloted rights for a percentage of their historical gasoline usage; States have more influence on the division of the total state supply between state reserves and vehicle allotments. The rationing plan, is described on a chart depicting the interaction of the principal components is included. The rationing process starts when checks for coupons are sent to owners of registered vehicles. The biggest single problem area appears to be delivering these checks into the hands of the vehicle registrants who are entitled to them. (DMC)
Date: March 5, 1980
Creator: unknown
System: The UNT Digital Library
Improving the performance of brine wells at Gulf Coast strategic petroleum reserve sites (open access)

Improving the performance of brine wells at Gulf Coast strategic petroleum reserve sites

At the request of the Department of Energy, field techniques were developed to evaluate and improve the injection of brine into wells at Strategic Petroleum Reserve (SPR) sites. These wells are necessary for the disposal of saturated brine removed from salt domes where oil is being stored. The wells, which were accepting brine at 50 percent or less of their initial design rates, were impaired by saturated brine containing particulates that deposited on the sand face and in the geologic formation next to the wellbore. Corrosion of the brine-disposal pipelines and injection wells contributed to the impairment by adding significant amounts of particulates in the form of corrosion products. When tests were implemented at the SPR sites, it was found that the poor quality of injected brines was the primary cause of impaired injection; that granular-media filtration, when used with chemical pretreatment, is an effective method for removing particulates from hypersaline brine; that satisfactory injection-well performance can be attained with prefiltered brines; and that corrosion rates can be substantially reduced by oxygen-scavenging.
Date: November 5, 1979
Creator: Owen, L.B. & Quong, R. (eds.)
System: The UNT Digital Library
Investigation of photovoltaic mechanisms in polycrystalline thin-film solar cells. Interim technical report, November 1, 1980-July 31, 1981 (open access)

Investigation of photovoltaic mechanisms in polycrystalline thin-film solar cells. Interim technical report, November 1, 1980-July 31, 1981

Effort is reported on measurement technique development to assess the utility of Deep-Level Transient Spectroscopy (DLTS) methods in characterizing polycrystalline silicon that was deliberately doped with Ti during growth. Difficulties encountered with lateral DLTS measurements are discussed. In this approach, modulation of the grain boundary, double-depletion region produces the entire DLTS signal. Major effort has been applied in grain boundary characterization and control. The most significant accomplishments to date have involved laser scanning of slices of Wacker SILSO polysilicon having nearly identical grain structure. By using various kinds of treatments and by comparing treated and untreated substrates having nearly identical grain structure, control of grain boundary photocurrent suppression (..delta..I/sub ph/) over the range 1% less than or equal to ..delta..I/sub ph/ less than or equal to 40% was demonstrated.
Date: March 5, 1982
Creator: Temofonte, T. A.; Szedon, J. R. & O'Keeffe, T. W.
System: The UNT Digital Library
Investigation of Clean Water Test Sites for Prototype Turbomachinery (open access)

Investigation of Clean Water Test Sites for Prototype Turbomachinery

Expanded development of total-flow expander technology in order to obtain efficient energy extraction from the liquid flow component of the geothermal well flow, in addition to steam enthalpy conversion, has been undertaken by the University of California, Lawrence Livermore Laboratory (LLL). The flow conditions necessary for this type of complete system performance characterization are beyond the capabilities of the test facility utilized in the preliminary tests at the LLL hot-water test facility. As an alternative to increasing the existing facility to meet the expanded test requirements, test facilities in the industrial California community are being surveyed to assess their capability in supporting future tests of the LLL expander. Biphase Engines, Inc. of Santa Monica, California was contracted by LLL to perform this survey. The goal of the Biphase Engines survey is to identify organizations with, first, an interest in supporting the LLL turbine test program and, second, to review their test capabilities with respect to the turbine test requirements. The results of the survey are described in the following sections which includes a listing of all organizations contacted. The responses to all inquiries are given. The affirmative responses to the test-support requirement are detailed with a description of the test …
Date: January 5, 1978
Creator: Cerini, Donald J.
System: The UNT Digital Library
ARM tropical pacific experiment (ATPEX): Role of cloud, water vapor and convection feedbacks in the coupled ocean/atmosphere system (open access)

ARM tropical pacific experiment (ATPEX): Role of cloud, water vapor and convection feedbacks in the coupled ocean/atmosphere system

We have initiated studies that include radiation model validation, improved treatment of the three-dimensional structure of cloud-radiation interactions, and sensitivity runs that will unravel the role of cloud-convection-radiation interactions in the Pacific Sear Surface Temperatures and the overlying Walker and Hadley circulation. The research program is divided into three phases: (1) radiation, (2) cloud parameterization issues; (3) feedback and ocean-atmosphere interactions.
Date: March 5, 1992
Creator: Ramanathan, V. & Barnett, T.P.
System: The UNT Digital Library
Readily implemented enhanced sinusoid detection in noise (open access)

Readily implemented enhanced sinusoid detection in noise

Significant efforts have been devoted, spanning many years, to the problem of sinusoid detection in noise. Many of these efforts have produced superb, yet complex, algorithms which may be difficult to use for a wide segment of the Digital Signal Processing (DSP) community. This paper presents a simple, easily implemented and high effective method which solves this problem. This method severely degrades non-sinusoidal noise while leaving the embedded sinusoid(s) relatively undisturbed. The algorithm, simply put, exploits the difference between the net effect of integration and differentiation of sinusoids versus the effect of these operations on random noise and other signal sequences. The cross-correlation of sine wave with its differentiated (and/or integrated) self is quite high. Conversely, the cross-reduction of a noise sequence with its differentiated (and/or integrated) self is much lower. Therefore, it is reasonable to assume that for sequences consisting of a sinusoid in noise, significant signal-to-noise-ratios (SNRs) in the correlation results are achievable using a combination of differentiation (and/or integration) and cross-correlation operations on such sequences. This technique has been applied to actual Doppler radar data, as well as to synthesized data, with excellent improvement in signal detection capability. 4 refs.
Date: March 5, 1992
Creator: Lindsay, K.V.
System: The UNT Digital Library
Cultural noise in EM prospecting for geothermal resources. Final report (open access)

Cultural noise in EM prospecting for geothermal resources. Final report

Numerical analysis tools are used to characterize the fields reradiated by cultural scatterers like powerlines, pipelines and fences. These fields are then compared to the returns expected from deeply buried targets and suggestions are made for methods to identify and remove cultural noise from survey data.
Date: February 5, 1981
Creator: Merewether, D.E.; Cox, R.W. & Pate, R.C.
System: The UNT Digital Library
Powerplant Productivity. Improvement Study: current practices in Illinois utilities towards powerplant productivity. Final report, Project 1, Task 1 (open access)

Powerplant Productivity. Improvement Study: current practices in Illinois utilities towards powerplant productivity. Final report, Project 1, Task 1

Efforts of this task indicate that powerplant productivity is a complex issue that has to take into account economic factors, equipment limitations, and system-loading characteristics as well as external constraints such as regulatory requirements. Among the specific findings are: (1) utilities in Illinois use the industry-wide measures of performance such as capacity factor, availability factor, forced outage rates etc.; equivalent availability as a measure is not in common practice; (2) several unit performance statistics are collected on a routine basis such as the daily unit status, component outage data, monthly production figures etc.; (3) identifying major causes of lost productivity appears to be a relatively simple task, but finding economically and technically acceptable corrective actions are generally more difficult; (4) selection of improvement projects, as well as evaluating their future impacts, is mostly based on operating experience and engineering judgement, with no use of formal analytical/statistical models; (5) there generally is a group in every utility - typically called the power production department - with routine responsibilities for upkeep of unit productivity; and (6) recently the Commonwealth Edison Co. has developed a procedure for utilizing the Edison Electric Institute outage data base for analyzing productivity-related questions at nuclear plants; this …
Date: April 5, 1979
Creator: unknown
System: The UNT Digital Library
EDOT: a code to calculate charge particle slowing down in a plasma (open access)

EDOT: a code to calculate charge particle slowing down in a plasma

EDOT is a code that calculates the slowing down of a test particle in a Maxwellian plasma utilizing continuous slowing down theory. Both nuclear scattering and reactions are included. The output includes slowing down parameters as well as spectra of knock-on ions and in-flight reaction probabilities. The theory, input, and output for the code are described.
Date: August 5, 1977
Creator: Perkins, S. T.
System: The UNT Digital Library
Development of low level liquid waste treatment systems: April-September 1981 (open access)

Development of low level liquid waste treatment systems: April-September 1981

The pilot plant reverse osmosis system was demonstrated to be effective in removing large percentages of cobalt-60, iodine-125, and a mixture of cesium-137, cobalt-60, and iodine-125 from two types of aqueous streams. The effectiveness of three membrane porosities, 0, 50, and 97% salt rejection, were explored with each isotope. The 97% salt rejection membrane was the most effective in each experiment. Removals as high as 97.5% of the cobalt, 92.9% of the iodine and 95.1% of the combined isotopes were achieved. The effect of possibly interfering factors on the adsorbence of cobalt-60 and iodine-129 on selected ion exchange resins were investigated. The factors thought to affect cobalt-60 adsorption were (OH/sup -/), (NH/sub 4//sup +/), and (SO/sub 3//sup =/). None of the seven factors investigated had any effect on iodine-129 adsorption. Cesium-137 was removed from a 4600-gal aqueous waste containing a large amount of sodium hydroxide by treatment with sodium tetraphenyl boron. The cesium concentration of the supernatant portion was reduced from 570 to 4 counts/min/ml.
Date: March 5, 1982
Creator: Williams, M.K.; Colvin, C.M. & Bond, W.H.
System: The UNT Digital Library
Ductile-Brittle Transition Temperature testing of tungsten using the three-point bend test (open access)

Ductile-Brittle Transition Temperature testing of tungsten using the three-point bend test

Three-point bend tests were performed to determine the Ductile-Brittle Transition Temperatures (DBTTs) of forged and chemical vapor deposition (CVD) tungsten. Testing was performed under quasi-static conditions at temperatures between 23{degrees}C and 450{degrees}C using a forced-air environmental chamber. Load-displacement data from the three-point bend tests indicated that the constitutive behavior of the materials tested varied considerably. Finite element modeling of the three-point bend test was performed to investigate plastic strains induced in the samples during testing as a function of constitutive behavior. The modeling assumed plane stress conditions in the sample and simple bi-linear elastic-plastic constitutive behavior of the test material. The strains induced in the samples were found to be functions of both the yield stress and work hardening behavior of the materials. The use of the three-point bend test to determine DBTT, and the DBTTs reported for the test materials, are discussed relative to the modeling results. It is concluded that the three-point bend test has some utility in the determination of DBTTs if some caution is used in the selection of test parameters and fixture geometries. However, the three-point bed test does not provide a complete picture of the nature of the ductile-brittle transition. 12 refs., 9 figs.
Date: March 5, 1991
Creator: Lassila, D.H.; Magness, F. & Freeman, D.
System: The UNT Digital Library
Design of the Target Fabrication Tritium Laboratory (open access)

Design of the Target Fabrication Tritium Laboratory

The design of the Target Fabrication Tritium Laboratory for deuterium-tritium fuel processing for laser fusion targets has been accomplished with the intent of providing redundant safeguard systems. The design of the tritium laboratory is based on a combination of tritium handling techniques that are currently used by experienced laboratories. A description of the laboratory in terms of its interrelated processing systems is presented to provide an understanding of the design features for safe operation.
Date: May 5, 1982
Creator: Sherohman, J. W.; Roberts, D. H. & Levine, B. H.
System: The UNT Digital Library
Effect of electrical potential on scale formation in Salton Sea brine (open access)

Effect of electrical potential on scale formation in Salton Sea brine

None
Date: November 5, 1975
Creator: Schock, R. N. & Duba, A.
System: The UNT Digital Library