Partner
UNT Libraries Government Documents Department
3,422
Texas Historical Commission
1,576
Oklahoma Historical Society
219
UNT Libraries Special Collections
123
Abilene Christian University Library
13
Oklahoma State Firefighters Museum
11
Sterling Municipal Library
11
Carl Albert Congressional Research and Studies Center
10
Cooke County Library
10
UNT Music Library
9
75 More
Collection
Office of Scientific & Technical Information Technical Reports
3,380
THC National Register Collection
1,575
Texas Digital Newspaper Program
173
Oklahoma Publishing Company Photography Collection
138
Oklahoma Digital Newspaper Program
104
KXAS-NBC 5 News Collection
96
Tocker Foundation Grant
79
Texas Attorney General Opinions
15
Texas State Publications
14
Chickasha Newspaper Collection
13
116 More
Degree Department
Degree Discipline
Degree Level
Country
Year
Month
Day
Design analysis and optimization of self-cooled lithium blankets and shields
A study of self-cooled lithium blankets was carried out to define the performance of these blankets and to determine the potential to operate at the maximum possible values of the performance parameters. The main design parameters considered during the course of the study were the tritium breeding ratio, the blanket energy multiplication factor, the energy fraction lost to the shield, the total blanket thickness, the reflector material selection, and the compositions of the different blanket zones. Another study was carried out to determine materials, compositions, arrangements, and thickness of the shield zone for the reference blanket. Helium and water-cooled shields were optimized for the inboard and outboard sections of the reactor. Based on the above two studies, the reference blanket and shield configurations were developed for the ANL Tokamak Power Systems Study. The helium-cooled shield was selected for use with liquid metal blankets to reduce safety concerns related to lithium-water reactivity. This helium-cooled shield provides shielding characteristics similar to a conventional water-cooled shield. The analyses and results from these studies are the subject of this paper. 12 refs., 4 figs., 2 tabs.
Date:
February 1, 1988
Creator:
Gohar, Y.
Object Type:
Article
System:
The UNT Digital Library
Experimental and analytical studies of passive shutdown heat removal from advanced LMRs (liquid metal reactors)
A facility designed and constructed to demonstrate the viability of natural convection passive heat removal systems as a key feature of innovative LMR Shutdown Heat Removal (SHR) systems is in operation at Argonne National Laboratory (ANL). This Natural Convection Shutdown Heat Removal Test Facility (NSTF) has investigated the heat transfer performance of the GE/PRISM passive design. This initial series of experiments simulates the air-side geometry of the PRISM Radiant Reactor Vessel Auxiliary Cooling System (RVACS). The NSTF operates in either a uniform heat flux mode and a uniform temperature mode at the air/guard vessel interface. Analysis of the RVACS performance data indicates excellent agreement with pretest analytical predictions. Correlation analysis presents the heat transfer data in a form suitable for use in LMR design and verification of analytical studies.
Date:
January 1, 1988
Creator:
Pedersen, D.; Heineman, J.; Stewart, R.; Anderson, T.; Lottes, P. & Tessier, J.
Object Type:
Article
System:
The UNT Digital Library
Two-photon (VUV + visible) resonance ionization spectroscopy of molecular hydrogen
Two-photon transitions have been examined in molecular hydrogen using coherent vacuum ultraviolet (VUV) photons at a fixed wavelength of 118 nm and a tunable photon from a dye laser. Though the VUV intensity is very weak (/approximately/100 nJ per pulse) it was utilized very efficiently since most VUV photons in the ionoization region were absorbed. This is the first time that coherent VUV light has been employed with tunable visible light for the production of two-photon spectra and the measurement of two-photon rates. A new parameter is proposed for direct comparison of the data from various two-photon experiments. 4 refs., 2 figs., 1 tab.
Date:
April 1, 1988
Creator:
McCann, M.P.; Chen, C.H. & Payne, M.G.
Object Type:
Article
System:
The UNT Digital Library
An outdoor test facility for the large-scale production of microalgae
The goal of the US Department of EnergySolar Energy Research Institute's Aquatic Species Program is to develop the technology base to produce liquid fuels from microalgae. This technology is being initially developed for the desert Southwest. As part of this program an outdoor test facility has been designed and constructed in Roswell, New Mexico. The site has a large existing infrastructure, a suitable climate, and abundant saline groundwater. This facility will be used to evaluate productivity of microalgae strains and conduct large-scale experiments to increase biomass productivity while decreasing production costs. Six 3-m/sup 2/ fiberglass raceways were constructed. Several microalgae strains were screened for growth, one of which had a short-term productivity rate of greater than 50 g dry wt m/sup /minus/2/ d/sup /minus/1/. Two large-scale, 0.1-ha raceways have also been built. These are being used to evaluate the performance trade-offs between low-cost earthen liners and higher cost plastic liners. A series of hydraulic measurements is also being carried out to evaluate future improved pond designs. Future plans include a 0.5-ha pond, which will be built in approximately 2 years to test a scaled-up system. This unique facility will be available to other researchers and industry for studies on microalgae …
Date:
March 1, 1988
Creator:
Johnson, D.A.; Weissman, J. & Goebel, R.
Object Type:
Article
System:
The UNT Digital Library
Performance of the Los Alamos expanding telescope
An expanding telescope can produce a very low divergence particle beam, provided that the beam optics have sufficient quality in order not to introduce large aberrations. Even as late as two years ago there were no theoretical beamline codes, and little experimental work that could describe the third-order aberrations introduced by an expanding telescope. A project was undertaken at Los Alamos National Laboratory to perform these calculations, and to build a telescope to confirm the predictions. It was installed at Argonne National Laboratory during the summer of 1987 and tested in a 50 MeV H/sup /-// beam. The telescope consisted of a singlet eyepiece and triplet objective lens with a twenty times magnification. It performed to the design specifications of twenty-five micro-radians beam divergence with a parallel beam focus. The measured geometric aberrations were found to be in agreement with the computer calculations.
Date:
January 1, 1988
Creator:
Dombeck, T.W.
Object Type:
Article
System:
The UNT Digital Library
Development of mild gasification process
Under a previous contract with Morgantown Energy Technology Center (METC), Department of Energy (DOE) Contract No. AC21-84MC21108, UCC Research Corporation (UCCRC) built and tested a 1500 lb/day Mild Gasification Process Development Unit (MGU). The MGU, as tested under the previous contract, is shown in Figure 1. Testing completed under the previous contract showed that good quality hydrocarbon liquids and good quality char can be produced in the MGU. However, the MGU is not optimized. The primary objectives of the current project are to optimize the MGU and determine the suitability of char for several commercial applications. The program consists of four tasks; Task 1 -- Test Plan; Task 2 -- Optimization of Mild Gasification Process; Task 3 -- Evaluation of Char and Char/Coal Blends as a Boiler/Blast Furnace Fuel; and Task 4 -- Analysis of Data and Preparation of Final Report. Task 1 has been completed while work continued on Task 2.
Date:
July 1, 1988
Creator:
Chu, C. I. C. & Derting, T. M.
Object Type:
Report
System:
The UNT Digital Library
ACE: AMY CDC (Central Drift Chamber) Fast Track Finder
The central drift chamber (CDC) of the AMY detector at the TRISTAN e/sup /+//e/sup /-// collider features its fine granularity and multi-band structure. The tracking software named ACE which makes the most of these features shows an excellent performance for reconstruction of high multiplicity events with highly collimated jets. The obtained reconstruction efficiency is 97% for the particles coming from within 5 cm of the primary vertex with p/sub t/ /approx gt/ 500 MeVc in the simulated hadronic events. The processing time is on average less than 300 ms per hadronic event (simulated or real) on a FACOM M-382 computer. 3 refs., 5 figs.
Date:
January 1, 1988
Creator:
Mori, T.
Object Type:
Article
System:
The UNT Digital Library
Application of artificial intelligence to melter control: Realtime process advisor for the scale melter facility
The Defense Waste Processing Facility (DWPF) at the Savannah River Plant (SRP) is currently under construction and when completed will process high-level radioactive waste into a borosilicate glass wasteform. This facility will consist of numerous batch chemical processing steps as well as the continuous operation of a joule-heated melter and its off-gas treatment system. A realtime process advisor system based on Artificial Intelligence (AI) techniques has been developed and is currently in use at the semiworks facility, which is operating a 2/3 scale of the DWPF joule-heated melter. The melter advisor system interfaces to the existing data collection and control system and monitors current operations of this facility. The advisor then provides advice to operators and engineers when it identifies process problems. The current system is capable of identifying process problems such as feed system pluggages and thermocouple failures and providing recommended actions. The system also provides facilities normally with distributed control systems. These include the ability to display process flowsheets, monitor alarm conditions, and check the status of process interlocks. 7 figs.
Date:
January 1, 1988
Creator:
Edwards, Jr, R E
Object Type:
Article
System:
The UNT Digital Library
Covariance analysis of n + 7Li data for ENDF/B-VI
A new covariance analysis of n/plus//sup 7/Li experimental data has been completed for Version VI of ENDFB. The analysis basically updates our 1981 work for ENDFB-V.2 to include new data that has become available since that time and to incorporate cross correlations between different experiments. The bulk of the new measured data consists of some 10 new (or newly revised) tritium-production measurements involving about 70 new data points. The new analysis results in only small changes in the previous evaluation of the tritium-production cross section but significantly reduces the magnitudes of uncertainties due to the more extensive and accurate data base that was used.
Date:
January 1, 1988
Creator:
Young, P.G.
Object Type:
Article
System:
The UNT Digital Library
Environmental surveillance at Los Alamos during 1987
This report describes the environmental surveillance program conducted by Los Alamos National Laboratory during 1987. Routine monitoring for radiation and radioactive or chemical materials is conducted on the Laboratory site as well as in the surrounding region. Monitoring results are used to determine compliance with appropriate standards and to permit early identification of potentially undesirable trends. Results and interpretation of data for 1987 cover: external penetrating radiation; quantities of airborne emissions and liquid effluents; concentrations of chemicals and radionuclides in ambient air, surface and ground waters, municipal water supply, soils and sediments, and foodstuffs; and environmental compliance. Comparisons with appropriate standards, regulations, and background levels provide the basis for concluding that environmental effects from Laboratory operations are insignificant and do not pose a threat to the public, Laboratory employees, or the environment. 113 refs., 33 figs., 120 tabs.
Date:
May 1, 1988
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
A theoretical prediction of critical heat flux in forced convection boiling during power transients
In this paper, a theoretical prediction of critical heat flux (CHF) during power transients in forced convective boiling is presented. The analysis is restricted to the departure from nucleate boiling (DNB) type of CHF at low qualities. The developed theory is compared with the experimental data available in the literature. The agreement is favorable. The results are discussed in terms of the various parameters affecting the transient CHF. This new model also is compared with the semi-empirical transient CHF model in the literature.
Date:
January 1, 1988
Creator:
Pasamehmetoglu, K.O.; Nelson, R.A. & Gunnerson, F.S.
Object Type:
Article
System:
The UNT Digital Library
Solar thermal bowl concepts and economic comparisons for electricity generation
This study is aimed at providing a relative comparison of the thermodynamic and economic performance in electric applications for fixed mirror distributed focus (FMDF) solar thermal concepts which have been studied and developed in the DOE solar thermal program. Following the completion of earlier systems comparison studies in the late 1970's there have been a number of years of progress in solar thermal technology. This progress includes developing new solar components, improving component and system design details, constructing working systems, and collecting operating data on the systems. This study povides an update of the expected performance and cost of the major components, and an overall system energy cost for the FMDDF concepts evaluated. The projections in this study are for the late 1990's and are based on the potential capabilities that might be achieved with further technology development.
Date:
April 1, 1988
Creator:
Williams, T. A.; Dirks, J. A.; Brown, D. R.; Antoniak, Z. I.; Allemann, R. T.; Coomes, E. P. et al.
Object Type:
Report
System:
The UNT Digital Library
Nuclear-data evaluation based on direct and indirect measurements with general correlations
Optimum procedures for the statistical improvement, or updating, of an existing nuclear-data evaluation are reviewed and redeveloped from first principles, consistently employing a minimum-variance viewpoint. A set of equations is derived which provides improved values of the data and their covariances, taking into account information from supplementary measurements and allowing for general correlations among all measurements. The minimum-variance solutions thus obtained, which we call the method of ''partitioned least squares,'' are found to be equivalent to a method suggested by Yu. V. Linnik and applied by a number of authors to the analysis of fission-reactor integral experiments; however, up to now, the partitioned-least-squares formulae have not found widespread use in the field of basic data evaluation. This approach is shown to give the same results as the more commonly applied Normal equations, but with reduced matrix inversion requirements. Examples are provided to indicate potential areas of application. 10 refs.
Date:
January 1, 1988
Creator:
Muir, D.W.
Object Type:
Article
System:
The UNT Digital Library
Radioactive Waste Isolation in Salt: A Method for Evaluating the Effectiveness of Site Characterization Measurements
The approach presumes that measurements are undertaken to support performance predictions. A quantitative performance objective like groundwater travel time is compared with performance predictions. The approach recognizes that such predictions are uncertain because the measurements upon which they are based are uncertain. The effectiveness of measurement activities is quantified by an index, ..beta.., that reflects the number of standard deviations separating the best estimate of performance from the performance objective. Measurements that reduce the uncertainty in predictions lead to increased values of ..beta... Evaluating ..beta.. for a particular measurement scheme requires identifying the measured quantities that significantly affect prediction uncertainty. Sources of uncertainty are spatial variation, noise, estimation error, and measurement bias. Changing the measurement scheme to increase ..beta.. increases the likelihood of a performance objective being achieved or exceeded. The application of the ..beta..-index method to the Richton dome site in Mississippi focuses on uncertainties in hydraulic conductivity data in relation to groundwater travel time predictions. The ..beta.. values for four different measurement schemes for hydraulic conductivity are determined. 44 refs., 14 figs., 15 tabs.
Date:
March 1, 1988
Creator:
Ditmars, J. D.; Baecher, G. B.; Edgar, D. E. & Dowding, C. H.
Object Type:
Report
System:
The UNT Digital Library
Beauty physics at Fermilab fixed target energies
The very high luminosities (>>10/sup 32/cm/sup /minus/2/sec/sup /minus/1/) available in the Fermilab fixed target experimental areas offer immediate opportunities for producing large samples (>10/sup 8/ of B hadrons in individual experiments. The possibilities of accumulating large samples of B decays are limited by experimental techniques and trigger strategies and not by available luminosity. At the present time one experiment, E771, is approved to begin B physics experimentation and several other experimental possibilities are being discussed. Some of the problems and the potential of B experiments at fixed target energies as B factories are discussed.
Date:
April 1, 1988
Creator:
Cox, B.
Object Type:
Report
System:
The UNT Digital Library
Electron-positron physics at 1 TeV
We discuss the motivation for TeV e/sup +/ e/sup )minus/) linear colliders, some aspects of their design, and the experimental consequences that follow from the design. After a brief discussion of the general physics environment, we consider the discovery potential of these colliders by examining three sample processes: the detection of new heavy leptons, standard Higgs bosons, and charged Higgs bosons. 13 refs., 22 figs., 5 tabs.
Date:
March 1, 1988
Creator:
Feldman, G. J.
Object Type:
Article
System:
The UNT Digital Library
Root cause analysis at the Savannah River Plant
Events (or near misses) provide important information about ways to improve plant performance. Any particular event may have several /open quotes/root causes/close quotes/ that need correcting to prevent recurrence of the event and, thereby, improve the safety of the plant. Also, by reviewing a large number of events, one can identify cause trends or /open quotes/generic concerns./close quotes/ A method has been developed at Savannah River Plant (SRP) to systematically evaluate events, identify their root causes, record the root causes, and analyze the root cause trends. By providing a systematic method to identify correctable root causes, the system helps the event investigator ask the right questions during the investigation. It also provides an independent safety analysis group and management with statistics indicating existing and developing trouble spots. 3 refs., 4 figs.
Date:
January 1, 1988
Creator:
Paradies, M & Busch, D
Object Type:
Article
System:
The UNT Digital Library
A proposal for a precision test of the standard model by neutrino-electron scattering (Large /hacek C/erenkov Detector Project)
A precision measurement of neutrino-electron elastic scattering from a beam stop neutrino source at LAMPF is proposed. The total error in sin/sup 2/theta/sub W/ is estimated to be +-0.89/percent/. The experiment also will be sensitive to neutrino oscillations and supernova-neutrino bursts, and should set improved limits on the neutrino-charge radius and magnetic-dipole moment. The detector consists of a 2.5-million-gallon tank of water with approximately 14,000 photomultiplier tubes lining the surfaces of the tank. Neutrino-electron scattering events will be observed from the /hacek C/erenkov radiation emitted by the electrons in the water. 19 refs.
Date:
April 1, 1988
Creator:
Allen, R. C.; Lu, X.-Q.; Gollwitzer, K.; Igo, G. J.; Gulmez, E.; Whitten, C. et al.
Object Type:
Report
System:
The UNT Digital Library
Sperm-head morphology study in B6C3F1 mice following inhalation exposure to 1,3-butadiene: Final technical report
The present report describes the results of a study of the morphology of epididymal sperm heads of B6C3F1 mice that were exposed to varying concentrations of 1,3-butadiene. During the fifth post-exposure week, the animals were killed and examined for gross lesions of the reproductive tract; suspensions of the epididymal sperm were prepared for morphologic evaluations. No mortality was observed in any of the inhalation exposure groups. Transient toxic signs, including piloerection and dyspnea, were evident during a 20- to 30-minute period following exposure to 5000 ppM. Mean values for body weights and weight gains of the mice exposed to 1,3-butadiene were not significantly different from control values. A concentration-related increase in the incidence of sperm-head abnormalities was evident and the percentage of sperm heads that were morphologically abnormal was significantly higher in mice exposed to 1000 and 5000 ppM than in the controls. 23 refs., 2 figs., 6 tabs.
Date:
April 1, 1988
Creator:
Hackett, P. L.; McClanahan, B. J.; Brown, M. G.; Buschbom, R. L.; Clark, M. L.; Decker, J. R. et al.
Object Type:
Report
System:
The UNT Digital Library
A subregion block iteration to 3-D finite element modeling of subsurface flow
A subregion block iteration (SBI) technique has been developed in conjunction with finite element approximations of saturated-unsaturated flow equations. The proposed SBI technique is implemented in a three-dimensional finite element saturated-unsaturated flow model. The model is verified with a nonlinear diffusion equation having an analytical solution. It is then applied to a burial trench problem. It is not possible to solve this field problem using the direct elimination finite element method. The SBI technique provides significant improvement over models based on direct band solution methods in both central processing unit (CPU) storage and CPU time. 5 refs., 2 figs.
Date:
January 1, 1988
Creator:
Yeh, G.T.
Object Type:
Article
System:
The UNT Digital Library
Development of biomass gasification to produce substitute fuels
The development of an efficient pressurized, medium-Btu steam-oxygen-blown fluidized-bed biomass gasification process was conducted. The overall program included initial stages of design-support research before the 12-ton-per-day (TPD) process research unit (PRU) was built. These stages involved the characterization of test-specific biomass species and the characteristics and limits of fluidization control. Also obtained for the design of the adiabatic PRU was information from studies with bench-scale equipment on the rapid rates of biomass devolatilization and on kinetics of the rate-controlling step of biomass char and steam gasification. The development program culminated with the sucessful operation of the PRU through 19 parametric-variation tests and extended steady-state process-proving tests. the program investigated the effect of gasifier temperature, pressure, biomass throughput rate, steam-to-biomass ratio, type of feedstock, feedstock moisture, and fludized-bed height on gasification performance. A long-duration gasification test of 3 days steady-state operation was conducted with the whole tree chips to indentify long-term effects of fluidized process conditions; to establish gasifier material and energy balances; to determine the possible breakthrough of low concentration organic species; and to evaluate the mechanical performance of the system components. Results indicate that the pressurized fludizied-bed process, can achieve carbon conversions of about 95% with cold gas thermal …
Date:
March 1, 1988
Creator:
Evans, R. J.; Knight, R. A.; Onischak, M. & Babu, S. P.
Object Type:
Report
System:
The UNT Digital Library
Microscopy and Elemental Analysis in Tissue Samples Using Computed Microtomography With Synchrotron X-Rays
The initial development shows that CMT using synchrotron x-rays can be developed to ..mu..m spatial resolution and perhaps even better. This creates a new microscopy technique which is of special interest in morphological studies of tissues, since no chemical preparation or slicing of the sample is necessary. The combination of CMT with spatial resolution in the ..mu..m range and elemental mapping with sensitivity in the ppM range results in a new tool for elemental mapping at the cellular level. 7 refs., 1 fig.
Date:
January 1, 1988
Creator:
Spanne, P. & Rivers, M. L.
Object Type:
Article
System:
The UNT Digital Library
Costs of nuclear waste glassmaking at Savannah River
Recently developed reference schedules for processing high-level nuclear wastes into solid glass froms at Savannah River provide bases for economic evaluations of potential improvements of glass melter design and operation. Greater melter output is achieved through increases in capacity and attainment and possible higher glass waste loadings. The economic evaluation indicates only minor beneficial impacts on total waste disposal costs for melter outputs greater than current reference values. In contrast, cost impacts are detrimentally large for outputs less than reference values, providing important incentives for development to ensure the reference output. The limits on cost benefits for greater-than-reference output are not intrinsic to on melter feed specified to control radiation and heat loads of the product glass waste form. 14 ref., 3 figs., 1 tab.
Date:
January 1, 1988
Creator:
McDonell, W R; Thomas, S D & Goodlett, C B
Object Type:
Article
System:
The UNT Digital Library
Some fundamental aspects of the optical potential for the interaction of fast neutrons with cobalt
Differential elastic- and inelastic-scattering cross sections, measured from approx.1.5 to 10.0 MeV, are interpreted in terms of spherical-optical-statistical (OM) and coupled-channels models. A successful description of the differential elastic scattering below 10 MeV and the total cross section to 20.0 MeV is achieved using the spherical OM with energy-dependent strengths and geometries. These energy dependencies are large below approx.7.0 MeV, but become smaller and similar to those reported for /open quotes/global/close quotes/ potentials at higher energies. This change in the energy dependence of the parameters probably marks the onset of the Fermi surface anomaly approx.19 MeV above the Fermi energy. Inelastic scattering to the levels below 1.8 MeV displays a forward-peaked behavior. This nonstatistical component is interpreted using the weak-coupling model in which the f/sub 7/2 proton hole is coupled to the 2/sup /plus// state in /sup 60/Ni. This model provides an explanation of the unusual energy dependence and relatively small radius found for the imaginary OM potential. The coupling also contributes to the large value of this potential. The real spherical OM potential derived from the neutron-scattering results is extrapolated to bound energies by using the dispersion relationship and the method of moments. The resulting real-potential strength and radius …
Date:
January 1, 1988
Creator:
Smith, A. B. & Lawson, R. D.
Object Type:
Article
System:
The UNT Digital Library