Partner
UNT Libraries Government Documents Department
13,590
Oklahoma Historical Society
1,640
UNT Libraries Special Collections
807
UNT Libraries
523
Rosenberg Library
197
UT San Antonio Libraries Special Collections
166
Abilene Library Consortium
121
Sterling Municipal Library
98
Abilene Public Library
51
Denton Public Library
44
232 More
Collection
Office of Scientific & Technical Information Technical Reports
12,964
Texas Digital Newspaper Program
2,696
Oklahoma Digital Newspaper Program
1,699
Tocker Foundation Grant
1,058
KXAS-NBC 5 News Collection
692
Abilene Library Consortium
283
Defense Base Closure and Realignment Commission
180
Congressional Research Service Reports
180
Texas Cultures Online
168
Harris and Eliza Kempner
154
584 More
Degree Department
Degree Discipline
Degree Level
Country
States
Decade
Month
Day
Language
19,464 Matching Results
Results open in a new window/tab.
Mechanism for Diffusion Induced Grain Boundary Migration
Grain boundaries are found to migrate under certain conditions when solute atoms are diffused along them. This phenomenon, termed diffusion induced grain boundary migration (DIGM), has now been found in six systems. The observed phenomenon and empirical data are used to discard certain concepts for the driving force and the mechanism. A mechanism is proposed in which differences in the diffusion coefficients of the diffusing species along the grain boundary cause a self-sustaining climb of grain boundary dislocations and motion of their associated grain boundary steps.
Date:
August 1, 1980
Creator:
Balluffi, R. W. & Cahn, J. W.
Object Type:
Report
System:
The UNT Digital Library
Radioactivities of Long Duration Exposure Facility (LDEF) materials: Baggage and bonanzas
Radioactivities in materials onboard the returned Long Duration Exposure Facility (LDEF) satellite have been studied by a variety of techniques. Among the most powerful is low-background Ge-semiconductor detector gamma-ray spectrometry, illustrated here by results obtained at the Lawrence Berkeley Laboratory's (LBL) Low Bakground Facilities, in a multi-laboratory collaboration coordinated by Dr. Thomas Parnell's team at the Marshall Spacecraft Center, Huntsville, Alabama.
Date:
August 1, 1991
Creator:
Smith, A. R. & Hurley, D. L.
Object Type:
Article
System:
The UNT Digital Library
Pu-238 fuel form activities, February 1-28, 1985
The Plutonium Fuel Form Facility (for producing /sup 238/PuO/sub 2/ for RTG's) remains in a production readiness mode of operation. (DLC)
Date:
August 1, 1985
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Inelastic processes in seismic wave generation by underground explosions
Theories, computer calculations, and measurements of spherical stress waves from explosions are described and compared, with emphasis on the transition from inelastic to almost-elastic relations between stress and strain. Two aspects of nonspherical explosion geometry are considered: tectonic strain release and surface spall. Tectonic strain release affects the generation of surface waves; spall closure may also. The reduced-displacement potential is a common solution (the equivalent elastic source) of the forward and inverse problems, assuming a spherical source. Measured reduced-displacement potentials are compared with potentials calculated as solutions of the direct and inverse problems; there are significant differences between the results of the two types of calculations and between calculations and measurements. The simple spherical model of an explosion is not sufficient to account for observations of explosions over wide ranges of depth and yield. The explosion environment can have a large effect on explosion detection and yield estimation. The best sets of seismic observations for use in developing discrimination techniques are for high-magnitude high-yield explosions; the identification problem is most difficult for low-magnitude low-yield explosions. Most of the presently available explosion data (time, medium, depth, yield, etc.) are for explosions in a few media at the Nevada Test Site; some …
Date:
August 1, 1980
Creator:
Rodean, H.C.
Object Type:
Report
System:
The UNT Digital Library
Glossary: Carbon dioxide and climate
This Glossary contains definitions of selected CO{sub 2}-related terms as well as tables containing information related to CO{sub 2} and climate. Each term is defined with an emphasis on its relationship to CO{sub 2} and climate. Many of the definitions are then followed by a more detailed description of the term and its use. References to the literature from which the definitions were taken are listed at the end of the Glossary.
Date:
August 1, 1990
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
SIZE ANALYSIS OF PARTICULATES FOUND IN AIR AT HANFORD PLUTONIUM FABRICATION FACILITIES
A study was made on the characteristics of radioactively contaminated air at Hanford work locations. One of the main objectives in this study is to define the size of particular air contamination in plutonium handling facilities. In addition to characterizing the particulate contamination, it is desirable to know the normal background particle size distribution. Data are summarized on general particle size distribution and radioactive particle distribution at two Hanford plutonium fabrication facilities. (auth)
Date:
August 1, 1962
Creator:
Selby, J.M.
Object Type:
Report
System:
The UNT Digital Library
Geology, hydrothermal petrology, stable isotope geochemistry, and fluid inclusion geothermometry of LASL geothermal test well C/T-1 (Mesa 31-1), East Mesa, Imperial Valley, California, USA
Borehole Mesa 31-1 (LASL C/T-1) is an 1899-m (6231-ft) deep well located in the northwestern part of the East Mesa Geothermal Field. Mesa 31-1 is the first Calibration/Test Well (C/T-1) in the Los Alamos Scientific Laboratory (LASL), Geothermal Log Interpretation Program. The purpose of this study is to provide a compilation of drillhole data, drill cuttings, well lithology, and formation petrology that will serve to support the use of well LASL C/T-1 as a calibration/test well for geothermal logging. In addition, reviews of fluid chemistry, stable isotope studies, isotopic and fluid inclusion geothermometry, and the temperature log data are presented. This study provides the basic data on the geology and hydrothermal alteration of the rocks in LASL C/T-1 as background for the interpretation of wireline logs.
Date:
August 1, 1980
Creator:
Miller, K. R. & Elders, W. A.
Object Type:
Report
System:
The UNT Digital Library
Fuel temperature determination for ICF microspheres
The common heuristic expression for estimating thermonuclear burn in ICF microspheres far from bootstrap heating is often used for inversion to obtain peak temperatures from experimental data. It contains an ad hoc or fitted parameter and lacks some parameters of obvious influence in actual systems. We present an alternative expression, which may be usefully inverted and does not suffer these defects.
Date:
August 1, 1980
Creator:
Henderson, D.B. & Giovanielli, D.V.
Object Type:
Report
System:
The UNT Digital Library
Geochemical orientation survey of stream sediment, stream water, and ground water near uranium prospects, Monticello area, New York. National Uranium Resource Evaluation Program
A detailed geochemical test survey has been conducted in a 570 sq km area around six small copper-uranium prospects in sandstones of the Devonian Catskill Formation near Monticello in southern New York state. This report summarizes and interprets the data for about 500 stream sediment samples, 500 stream water samples, and 500 ground water samples, each analyzed for 40 to 50 elements. The groundwater samples furnish distinctive anomalies for uranium, helium, radon, and copper near the mineralized localities, but the samples must be segregated into aquifers in order to obtain continuous well-defined anomalies. Two zones of uranium-rich water (1 to 16 parts per billion) can be recognized on cross sections; the upper zone extends through the known occurrences. The anomalies in uranium and helium are strongest in the deeper parts of the aquifers and are diluted in samples from shallow wells. In stream water, copper and uranium are slightly anomalous, as in an ore factor derived from factor analysis. Ratios of copper, uranium, and zinc to conductivity improve the resolution of anomalies. In stream sediment, extractable uranium, copper, niobium, vanadium, and an ore factor furnish weak anomalies, and ratios of uranium and copper to zinc improve the definition of anomalies. …
Date:
August 1, 1982
Creator:
Rose, A. W.; Smith, A. T. & Wesolowski, D.
Object Type:
Report
System:
The UNT Digital Library
Theoretical understanding of charm decays
A detailed description of charm decays has emerged. The various concepts involved are sketched. Although this description is quite successful in reproducing the data the chapter on heavy flavour decays is far from closed. Relevant questions like on th real strength of weak annihilation, Penguin operators, etc. are still unanswered. Important directions in future work, both on the experimental and theoretical side are identified.
Date:
August 1, 1986
Creator:
Bigi, I. I.
Object Type:
Article
System:
The UNT Digital Library
Suppression of superheavy magnetic monopoles in grand unified theories
The superheavy magnetic monopoles predicted by grand unified theories would not be produced in significant numbers if electromagnetic gauge invariance is spontaneously broken when the temperature T is greater than T/sub c/ >approx. 1 TeV.
Date:
August 1, 1980
Creator:
Pi, S.Y.
Object Type:
Article
System:
The UNT Digital Library
Study of rock-water-nuclear waste interactions in the Pasco Basin, Washington: Part II. Preliminary equilibrium-step simulations of basalt diagenesis
Interactions between a large number of complex chemical and physical processes have resulted in significant changes in the Pasco Basin hydrochemical system since emplacement of the first basalt flow. In order to perform preliminary simulations of the chemical evolution of this system, certain simplifying assumptions and procedures were adopted and a computer model which operates on the principal of local equilibrium was used for the mass transfer calculations. Significant uncertainties exist in both the thermodynamic and reaction rate data which were input to the computer model. In addition, the compositional characteristics of the evolving hydrochemical system remain largely unknown, especially as a function of distance along the flow path. Given these uncertainties, it remains difficult to assess the applicability of the equilibrium-step approach even though reasonable matches between observed and simulated hydrochemical data were obtained. Given the uncertainties mentioned, the predictive abilities of EQ6 are difficult, if not impossible to evaluate; our simulations produced, at best, only qualitative agreement with observed product mineral assemblages and sequences, and fluid compositions.
Date:
August 1, 1980
Creator:
Benson, L. V.; Carnahan, C. L. & Che, M.
Object Type:
Report
System:
The UNT Digital Library
CALCULATIONS OF THE DOPPLER COEFFICIENT OF LARGE CERAMIC-FUELED FAST REACTORS
ABS>Calculations of the Doppler coefficient of large, ceramicfueled fast reactors containing plutonium were made by means of the ELMOE program to provide accurate flux calculations. The temperature-dependent cross sections of P. Greebler et al., for U/sup 238/ and Pu/sup 239/ were used. Doppler coefficients of the order of 10/sup -5/ ntermediate tem k/ C were obtained, in agreement with Greebler's results. Coefficients of carbide fueled reactors are about 0.7 of those of oxide-fueled reactors at the same fuel enrichment. Effective coarse- group elastic-removal cross sections for light elements are tabulated. It appears that, with tabulations of this sort as a guide, coarse-group sets of cross sections can be constructed to give adequate accuracy in calculations of Doppler coefficients without use of ELMOE. (auth)
Date:
August 1, 1962
Creator:
Bhide, M.G. & Hummel, H.H.
Object Type:
Report
System:
The UNT Digital Library
Terrestrial perturbation experiments as an environmental assessment tool
The National Environmental Policy Act of 1969 (NEPA) was initially interpreted as requiring full disclosure of the environmental impacts of a federal action. Because of the limitations of time, money, and manpower, this requirement that all impacts be considered has led to superficial analysis of many important impacts. The President's Council on Environmental Quality (CEQ) has provided a solution to this problem by reinterpreting NEPA as requiring analysis of those impacts which have significant bearing on decision making. Because assessment resources can now be concentrated on a few critical issues, it should be possible to perform field perturbation experiments to provide direct evidence of the effects of a specific mixture of pollutants or physical disturbances on the specific receiving ecosystem. Techniques are described for field simulation of gaseous and particulate air pollution, soil pollutants, disturbance of the earth's surface, and disturbance of wildlife. These techniques are discussed in terms of their realism, cost, and the restrictions which they place on the measurement of ecological parameters.
Date:
August 1, 1980
Creator:
Suter, G. W. II
Object Type:
Report
System:
The UNT Digital Library
Techniques for analyzing the impacts of certain electric-utility ratemaking and regulatory-policy concepts. Regulatory laws and policies. [State by state]
This report is a legal study prepared to provide a review of the substantive and procedural laws of each regulatory jurisdiction that may affect implementation of the PURPA standards, and to summarize the current state of consideration and implementation of policies and rate designs similar or identical to the PURPA standards by state regulatory agencies and nonregulated utilities. This report is divided into three sections. The first section, the Introduction, summarizes the standards promulgated by PURPA and the results of the legal study. The second section, State Regulatory Law and Procedure, summarizes for each state or other ratemaking jurisdiction: (1) general constitutional and statutory provisions affecting utility rates and conditions of service; (2) specific laws or decisions affecting policy or rate design issues covered by PURPA standards; and (3) statutes and decisions governing administrative procedures, including judicial review. A chart showing actions taken on the policy and rate design issues addressed by PURPA is also included for each jurisdiction, and citations to relevant authorities are presented for each standard. State statutes or decisions that specifically define a state standard similar or identical to a PURPA standard, or that refer to one of the three PURPA objectives, are noted. The third …
Date:
August 1, 1980
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
F/H Area ETF effluent (H-016 outfall), ceriodaphnia survival/reproduction test, test date: March 21, 1991
This toxicity test was conducted to determine if the effluent from the F/H area at Savannah River Plant affects the survival or reproduction of the test organisms during a seven day period. The test involved exposing the test organisms to a series of dilutions of the effluent. At each dilution the survival and reproduction of ten test organisms was recorded. Each effluent dilution was compared to a control set of test organisms. Survival data were analyzed by Fisher's Exact Test and the Trimmed Spearman-Karber test to determine the effluent concentration necessary to cause statistically significant (p = 0.05) mortality. Reproduction data was analyzed for normality, homogeneity of variance and equality of replicates among dilutions to determine the appropriate statistical test for analysis of statistical differences in reproduction among dilutions. Results are summarized.
Date:
August 1, 1991
Creator:
Specht, Winona L.
Object Type:
Report
System:
The UNT Digital Library
Production and decay of heavy top quarks
Experimental evidence indicates that the top quark exists and has a mass between 50 and 200 GeV/c{sup 2}. The decays of a top quark with a mass in this range are studied with emphasis placed on the mass region near the threshold for production of real W bosons. Topics discussed are: (1) possible enhancement of strange quark production when M{sub W} + m{sub s} < m{sub t} < M{sub W} + m{sub b}; (2) exclusive decays of T mesons to B and B{asterisk} mesons using the non-relativistic quark model; (3) polarization of intermediate W's in top quark decay as a source of information on the top quark mass. The production of heavy top quarks in an e{sup +}e{sup {minus}} collider with a center-of-mass energy of 2 TeV is studied. The effective-boson approximation for photons, Z{sup 0}'s and W's is reviewed and an analogous approximation for interfaces between photons and Z{sup 0}'s is developed. The cross sections for top quark pair production from photon-photon, photon-Z{sup 0}, Z{sup 0}Z{sup 0}, and W{sup +}W{sup {minus}} fusion are calculated using the effective-boson approximation. Production of top quarks along with anti-bottom quarks via {gamma}W{sup +} and Z{sup 0}W{sup +} fusion is studied. An exact calculation …
Date:
August 1, 1989
Creator:
Kauffman, R.P.
Object Type:
Report
System:
The UNT Digital Library
Quantum electrodynamics with complex fermion mass
The quantum electrodynamics (QED) with a complex fermion mass -- that is, a fermion mass with a chiral phase -- is restudied, together with its chirally rotated version. We show how fake electric dipole moment can be obtained and how to avoid it. 10 refs.
Date:
August 1, 1991
Creator:
McKellar, B. J. H. & Wu, D. D.
Object Type:
Report
System:
The UNT Digital Library
Three-dimensional free electron laser dispersion relation including betatron oscillations
We have developed a 3-D FEL theory based upon the Maxwell-Vlasov equations including the effects of the energy spread and emittance of the electron beam, and of betatron oscillations. The radiation field is expressed in terms of the Green's function of the inhomogeneous wave equation and the distribution function of the electron beam. The distribution function is expanded in terms of a set of orthogonal functions determined by the unperturbed particle distribution. The coupled Maxwell-Vlasov equations are then reduced to a matrix equation, from which a dispersion relation for the eigenvalues is derived. In the limit of small betatron oscillation frequency, the present dispersion relation reduces to the well-known cubic equation of the one-dimensional theory in the limit of large beam size, and it gives the correct gain in the limit of small beam size. Comparisons of our numerical results with other approaches show good agreement. We present a handy empirical formula for the FEL gain of a 3-D Gaussian beam, as a function of the scaled parameters, that can be used for a quick estimate of the grain. 5 refs., 2 figs.
Date:
August 1, 1991
Creator:
Chin, Y. H.; Kim, K. J. & Xie, M.
Object Type:
Article
System:
The UNT Digital Library
Silicon ingot casting: Heat Exchanger Method (HEM)/multi-wire slicing: Fixed Abrasive Slicing Technique (FAST), Phase IV. Quarterly progress report No. 2, April 1, 1980-June 30, 1980
Silicon ingot size cast by HEM has been extended to 34 cm x 34 cm x 10 cm. A 20 kg ingot has been solidified at 3 kg/hr with no crucible attachment or ingot cracking problems. Another ingot of 26 kg weight has also been solidified. The heat treatment used to develop a graded structure caused cracking on the inside surface of the first large crucibles. The thermal conditions were altered to minimize high gradients and the cracking was eliminated. A high degree of single crystallinity has been maintained as the size of the ingots has been increased. A graphite retainer made out of flat plates was used to produce an ingot with flat sides and rounded curves. It is now possible to electroplate diamonds only on the cutting edge of the wire. The advantages associated with diamonds on the cutting edge only are lower kerf, improved accuracy by improved seating in the support rollers, and less degradation of the rollers. This has resulted in less wander of wires and will reduce costs by using less diamonds and less degradation of rollers. The main failure mechanism of wires - diamond pullout - has been minimized by using filler diamonds to …
Date:
August 1, 1980
Creator:
Schmid, F.; Khattak, C.P. & Basaran, M.
Object Type:
Report
System:
The UNT Digital Library
Radiological survey of the radioactive sands and residues at Lowman, Idaho
No uranium ore milling was performed at the Lowman site, which is located approximately 0.8 km northeast of the town of Lowman, Idaho. Nevertheless, approximately 80,000 metric tons of radioactive sands and residues from upgrading of heavy minerals by physical processing methods remain on the site grounds. Measurements of external gamma radiation 1 m above the surface showed exposure rates up to 2.4 mR/hr on site, but the exposure rate off site quickly dropped to the background level in all directions. Analysis of surface soil and sediment samples for /sup 226/Ra and /sup 232/Th indicated a limited spread of radioactive material.
Date:
August 1, 1980
Creator:
Haywood, F. F.; Burden, J. E.; Ellis, B. S.; Loy, E. T. & Shinpaugh, W. H.
Object Type:
Report
System:
The UNT Digital Library
Advanced materials for geothermal energy processes
The primary goal of the geothermal materials program is to ensure that the private sector development of geothermal energy resources is not constrained by the availability of technologically and economically viable materials of construction. This requires the performance of long-term high risk GHTD-sponsored materials R and D. Ongoing programs described include high temperature elastomers for dynamic sealing applications, advanced materials for lost circulation control, waste utilization and disposal, corrosion resistant elastomeric liners for well casing, and non-metallic heat exchangers. 9 refs.
Date:
August 1, 1985
Creator:
Kukacka, L. E.
Object Type:
Article
System:
The UNT Digital Library
Optimal Linfinity estimates for some Galerkin methods for the Dirichlet problem
Optimal L/sup infinity/ error estimates are established for a few different finite-element-type methods for the Dirichlet problem in a bounded domain. The methods are selected so as to avoid the necessity of imposing boundary conditions on the trial functions, usually difficult in practice. Three specific methods are treated. These are the method of interpolated boundary conditions and two methods of Nitsche. The trial spaces, S/sup h/, consist of continuous piecewise polynomials of degree less than or equal to K-1 with K greater than 2. The model problem treated is -..delta.. ..-->.. u = f in ..cap omega.., u = 0 on delta..cap omega.., ..cap omega.. contained in R/sup 2/. For each method, an approximate solution, u/sup h/, is constructed for h sufficiently small. The main result of this report states that the following error estimate holds for each method: norm (u--u/sup h/)/sub L/sup infinity/(..cap omega..)/ less than or equal to Ch/sup K/norm(u)/sub W/sub infinity//sup K/(..cap omega..)/.
Date:
August 1, 1977
Creator:
Goldstein, C I & Scott, R
Object Type:
Report
System:
The UNT Digital Library
Studies of heavy ion reactions and transuranic nuclei. Progress report, June 1, 1976--August 31, 1977. [Summaries of research activities at University of Rochester]
Separate abstracts were prepared for the 12 papers. (JFP)
Date:
August 1, 1977
Creator:
Huizenga, J. R.
Object Type:
Report
System:
The UNT Digital Library