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Some Comments on the La Primavera Geothermal Field, Mexico
The La Primavera geothermal field is located about 20 km west of the city of Guadalajara, Jalisco, in the western part of the Mexican Neovolcanic Axis. Initial results of five deep exploration wells (down to 2000 m depth) were very promising; measured downhole temperatures exceed 300/sup 0/C. During production, however, downhole temperatures dropped, and the chemistry of the fluids changed. The analysis of geologic, mineralogic, geochemical, and well completion data indicate that colder fluids flow down the wellbore from shallower aquifers cooling the upper zones of the geothermal reservoir. This problem is attributed to inadequate well completions. Doubts have arisen about continuing the exploration of the field because of the somewhat disappointing drilling results. However, a more thorough analysis of all available data indicates that a good geothermal prospect might exist below 3000 m, and that it could be successfully developed with appropriately located and completed wells.
Date:
December 1, 1983
Creator:
A., B. Dominguez & Lippmann, M. J.
Object Type:
Article
System:
The UNT Digital Library
Mexican-American Cooperative Program at the Cerro Prieto Geothermal Field: Recent Results of the Well-Drilling Program at Cerro Prieto
The results of the 1980 and 1981 well drilling activities at the Cerro Prieto geothermal field are summarized. Details are given on the new series of deeper wells completed in the western (older) part of the field (Cerro Prieto I), and on the development and step-out wells drilled in the eastern part of the field (Cerro Prieto II and III). Production characteristics of on-line and standby wells are discussed. Recent changes in well completion procedures are also described.
Date:
December 1, 1981
Creator:
A., B. Dominguez; Lippmann, M. J. & M., Francisco Bermejo
Object Type:
Report
System:
The UNT Digital Library
Some Comments on the La Primavera Geothermal Field, Mexico
The La Primavera geothermal field is located about 20 km west of the city of Guadalajara, Jalisco, in the western part of the Mexican Neovolcanic Axis. Initial results of five deep exploration wells (down to 2000 m depth) were very promising; measured downhole temperatures exceed 300{degrees}C. During production, however, downhole temperatures dropped, and the chemistry of the fluids changed. The analysis of geologic, mineralogic, geochemical, and well completion data indicate that colder fluids flow down the wellbore from shallower aqifers cooling the upper zones of the gothermal reservoir. This problem is attributed to inadequate well completions. Doubts have arisen about continuing the exploration of the field because of the somewhat disappointing drilling results. However, a more thorough analysis of all available data indicates that a good geothermal prospect might exist below 3000 m, and that it could be successfully developed with appropriately located and completed wells.
Date:
December 15, 1983
Creator:
A., Bernardo Dominguez & Lippmann, Marcelo J.
Object Type:
Article
System:
The UNT Digital Library
[Document with Handwritten Notes: AIDS ARMS Network]
A summary of caseload statistics from the AIDS ARMS Network listing out the number of clients and information about those clients. This document is followed by a map.
Date:
December 1, 1986
Creator:
AIDS ARMS Network
Object Type:
Text
System:
The UNT Digital Library
[Sub-contractors monthly service report, December 1988]
A monthly service report for the AIDS ARMS Network, Inc's sub-contractors dated December 1988 and revised February 20, 1989.
Date:
December 1988
Creator:
AIDS ARMS Network, Inc.
Object Type:
Report
System:
The UNT Digital Library
[The Gift]
A summary of the AIDS Interfaith Network's first year of expanding the operation and helping persons with AIDS in the North Texas region.
Date:
December 1989
Creator:
AIDS Interfaith Network
Object Type:
Text
System:
The UNT Digital Library
AIDS Update, Volume 3, Number 12, December 1988
Monthly newsletter describing news and events related to the AIDS Resource Center in Dallas, Texas as well as articles, letters, advice columns, and advertisements of interest to subscribers.
Date:
December 1988
Creator:
AIDS Resource Center (Dallas, Tex.)
Object Type:
Journal/Magazine/Newsletter
System:
The UNT Digital Library
AIDS Update, Volume 4, Number 11, December 1989
Monthly newsletter describing news and events related to the AIDS Resource Center in Dallas, Texas as well as articles, letters, advice columns, and advertisements of interest to subscribers.
Date:
December 1989
Creator:
AIDS Resource Center (Dallas, Tex.)
Object Type:
Journal/Magazine/Newsletter
System:
The UNT Digital Library
DIFFUSION IN VERY CHAOTIC HAMILTONIAN SYSTEMS
We study nonintegrable Hamiltonian dynamics: H(I,{theta}}) = H{sub 0}(I)+kH{sub 1}(I,{theta}) for large k; that is, far from integrability. An integral representation is given for the conditional probability P(I,{theta},t|I{sub 0},{theta}{sub 0},t{sub 0}) that the system is at I,{theta} at t, given it was at I{sub 0},{theta}{sub 0} at t{sub 0}. By discretizing time into steps of size {epsilon}, we show how to evatuate physical observables for large k, fixed {epsilon}. An explicit calculation of a diffusion coefficient in a two degree of freedom problem is reported. Passage to {epsilon} = 0, the original Hamiltonian flow, discussed.
Date:
December 1, 1980
Creator:
Abarbanel, Henry D.I. & Crawford, John David
Object Type:
Article
System:
The UNT Digital Library
STRONG COUPLING EXPANSIONS FOR NON-INTEGRABLE HAMILTONIAN SYSTEMS
We present a method for studying nonintegrable Hamiltonian systems H(I,{theta})=H{sub 0}(I)+kH{sub 1}(I,{theta}) (I,{theta} are action-angle variables) in the reg1me of large k. Our central tool is the conditional probability P(I,{theta},t|I{sub 0},{theta}{sub 0},t{sub 0}) that the system is at I,{theta} at time t given that it resided at I{sub 0},{theta}{sub 0} at t{sub 0}. An integral representation is given for this conditional probability. By discretizing the Hamiltonian equations of motion in small time steps, {epsilon}, we arrive at a phase volume preserving mapping which replaces the actual flow. When the motion on the energy surface E=H(I,{theta}) is bounded we are able to evaluate physical quantities of interest for large k and fixed {epsilon}. We also discuss the representation of P(I,{theta},t|I{sub 0},{theta}{sub 0},t{sub 0}) when an external random forcing is added in order to smooth the singular functions associated with the deterministic flow. Explicit calculations of a "diffusion" coefficient are given for a non-integrable system with two degrees of freedom. The limit {epsilon}{approaches}0 , which returns us to the actual flow, is subtle and is discussed.
Date:
December 1, 1980
Creator:
Abarbanel, Henry D.I. & Crawford, John David
Object Type:
Article
System:
The UNT Digital Library
Water supply and demand in an energy supply model
This report describes a tool for water and energy-related policy analysis, the development of a water supply and demand sector in a linear programming model of energy supply in the United States. The model allows adjustments in the input mix and plant siting in response to water scarcity. Thus, on the demand side energy conversion facilities can substitute more costly dry cooling systems for conventional evaporative systems. On the supply side groundwater and water purchased from irrigators are available as more costly alternatives to unappropriated surface water. Water supply data is developed for 30 regions in 10 Western states. Preliminary results for a 1990 energy demand scenario suggest that, at this level of spatial analysis, water availability plays a minor role in plant siting. Future policy applications of the modeling system are discussed including the evaluation of alternative patterns of synthetic fuels development.
Date:
December 1, 1980
Creator:
Abbey, D & Loose, V
Object Type:
Report
System:
The UNT Digital Library
Theoretical Atomic Physics code development IV: LINES, A code for computing atomic line spectra
A new computer program, LINES, has been developed for simulating atomic line emission and absorption spectra using the accurate fine structure energy levels and transition strengths calculated by the (CATS) Cowan Atomic Structure code. Population distributions for the ion stages are obtained in LINES by using the Local Thermodynamic Equilibrium (LTE) model. LINES is also useful for displaying the pertinent atomic data generated by CATS. This report describes the use of LINES. Both CATS and LINES are part of the Theoretical Atomic PhysicS (TAPS) code development effort at Los Alamos. 11 refs., 9 figs., 1 tab.
Date:
December 1, 1988
Creator:
Abdallah, J. Jr. & Clark, R.E.H.
Object Type:
Report
System:
The UNT Digital Library
Theoretical atomic physics code development I: CATS: Cowan Atomic Structure Code
An adaptation of R.D. Cowan's Atomic Structure program, CATS, has been developed as part of the Theoretical Atomic Physics (TAPS) code development effort at Los Alamos. CATS has been designed to be easy to run and to produce data files that can interface with other programs easily. The CATS produced data files currently include wave functions, energy levels, oscillator strengths, plane-wave-Born electron-ion collision strengths, photoionization cross sections, and a variety of other quantities. This paper describes the use of CATS. 10 refs.
Date:
December 1, 1988
Creator:
Abdallah, J. Jr.; Clark, R.E.H. & Cowan, R.D.
Object Type:
Report
System:
The UNT Digital Library
A Comparison of the Reporting of International News in Two Algerian and Two United States Daily Newspapers
This study was concerned with determining how the Algerian dailies, El Moudjahid, and El Djomhouria, and the United States dailies, The New York Times and The Christian Science Monitor, which function in two different press systems, compare in reporting international news in terms of type and tension. This study concludes that the four dailies are similar in type of news; they report more news than editorials, more straight news than in-depth reports, more news of elites than common people, and more news from the Third World than from the Western World or the socialist bloc, and they differ in tension in that the tension within international news was higher in the two United States dailies than in the two Algerian dailies.
Date:
December 1980
Creator:
Abderrahmane, Azzi
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Crustal Rock Fracture Mechanics for Design and Control of Artificial Subsurface Cracks in Geothermal Energy Extraction Engineering ({Gamma}-Project)
Recently a significant role of artificial and/or natural cracks in the geothermal reservoir has been demonstrated in the literatures (Abe, H., et al., 1983, Nielson, D.L. and Hullen, J.B., 1983), where the cracks behave as fluid paths and/or heat exchanging surfaces. Until now, however, there are several problems such as a design procedure of hydraulic fracturing, and a quantitative estimate of fluid and heat transfer for reservoir design. In order to develop a design methodology of geothermal reservoir cracks, a special distinguished research project, named as ''{Lambda}-Project'', started at Tohoku University (5 years project, 1983-1988). In this project a basic fracture mechanics model of geothermal reservoir cracks is being demonstrated and its validation is being discussed both theoretically and experimentally. This paper descibes an outline of ''{Lambda}-Project''.
Date:
December 15, 1983
Creator:
Abe, Hiroyuki & Takahashi, Hideaki
Object Type:
Article
System:
The UNT Digital Library
Behaviors of Crack-Like Reservoirs by Means of Fracturing at Nigorikawa and Kakkonda Geothermal Fields
A basic concept of the geothermal reservoir as a set of cracks is first presented. Extensions of subsurface cracks during well stimulation treatments at Nigorikawa(Mori) and closure operations of production well-head valves at Kakkonda are analysed and their behaviors are demonstrated based on results of long-distance AE Measurements.
Date:
December 15, 1983
Creator:
Abe, Hiroyuki; Takahashi, Hideaki; Nakatsuka, Katsuto; Niitsuma, Hiroaki & Takanohashi, Morihiko
Object Type:
Article
System:
The UNT Digital Library
Locus of Control and Adjustment to Retirement
Locus of desired control and participation in a retirement preparation program was investigated in relation to retirement attitudes and adjustment. Fifty-nine subjects, consisting of older workers and retirees from a large southwestern corporation, comprised the sample. An experimental group, consisting of 12 subjects, completed questionnaires prior to and following their participation in the retirement preparation program. A control group, consisting of 15 subjects, completed the same questionnaires at approximately the same times as did the experimental group, but did not receive retirement preparation. A third group, consisting of 20 retirees who had a previous retirement preparation experience and 12 retirees who had not had such a retirement preparation experience, completed similar questionnaires.
Date:
December 1982
Creator:
Abel, Bruce Jules
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
[RE: Exhibition Space at Regional Institute Team Meeting February 1 - 4, 1990, Chattanooga, Tennessee]
A memo from Julie Abel, program associate for the Getty Center for Education in the Arts, to Jack Davis and William McCarter, co-directors of North Texas Institute for Educators on the Visual Arts. The memo is in regards to reserved exhibition space in the Bessie Smith room at the Radisson Read House, where reach regional institute can display any materials or information on their consortium.
Date:
December 19, 1989
Creator:
Abel, Julie
Object Type:
Letter
System:
The UNT Digital Library
Exchange of bonded hydrogen in amorphous silicon by deuterium
We show that bonded hydrogen in a-Si:H is readily exchanged by atomic deuterium when exposed to a deuterium plasma discharge. The effective diffusion coefficient for the D,H exchange 10/sup -14/ cm/sup 2//sec at 160/sup 0/C, is comparable to that of interstitial hydrogen in c-Si.
Date:
December 1, 1986
Creator:
Abeles, B.; Yang, L.; Leta, D.P. & Majkrzak, C.F.
Object Type:
Article
System:
The UNT Digital Library
Abilene Philharmonic Playbill: December 16, 1989
Program for an Abilene Philharmonic concert that ran on December 16th during the 40th season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date:
December 1989
Creator:
Abilene Philharmonic
Object Type:
Pamphlet
System:
The Portal to Texas History
A novel approach to highly dispersing catalytic materials in coal for gasification. First quarterly report, October 1, 1989--December 31, 1989
This project seeks to develop a technique, based on coal surface properties, for highly dispersing catalysts in coal for gasification and to investigate the potential of using potassium carbonate and calcium acetate mixtures as catalysts for coal gasification. The lower cost and high catalytic activity of the latter compound will produce economic benefits by reducing the amount of K{sub 2}CO{sub 3} required for high coal char reactivities. The work is focused on the elucidation of coal-catalyst precursor interactions in solution and the variables which control the adsorption and dispersion of coal gasification metal catalysts. In order to optimize coal-metal ion interactions and hence maximize catalyst activity, the study examines the surface electrochemistry of a lignite, a subbituminous, and a bituminous coals and their demineralized and oxidized derivatives prior to loading with the catalytic materials. The surface electrical properties of the coals are investigated with the aid of electrophoresis, while the effects of the surface charge on the adsorption of K{sup +} and Ca{sup 2+} are studied by agitating the coals with aqueous solutions of potassium and calcium. A zeta meter, a tube furnace, and other equipment required for the investigation have been acquired and installed. Preliminary work shows that the …
Date:
December 31, 1989
Creator:
Abotsi, G. M. K. & Bota, K. B.
Object Type:
Report
System:
The UNT Digital Library
Sequence dependent structure and thermodynamics of DNA oligonucleotides and polynucleotides: uv melting and NMR (nuclear magnetic resonance) studies
Thermodynamic parameters for double strand formation have been measured for the twenty-five DNA double helices made by mixing deoxyoligonucleotides of the sequence dCA/sub 3/XA/sub 3/G with the complement dCT/sub 3/YT/sub 3/G. Each of the bases A, C, G, T, and I (I = hypoxanthine) have been substituted at the positions labeled X and Y. The results are analyzed in terms of nearest neighbors. At higher temperatures the sequences containing a G)centerreverse arrowdot)C base pair become more stable than those containing only A)centerreverse arrowdot)T. All molecules containing mismatcher are destabilized with respect to those with only Watson-Crick pairing, but there is a wide range of destabilization. Large neighboring base effects upon stability were observed. For example, when (X, Y) = (I, A), the duplex is eightfold more stable than when (X, Y) = (A, I). Independent of sequence effects the order of stabilities is: I)centerreverse arrowdot)C )succ) I)centerreverse arrowdot) A)succ) I)centerreverse arrowdot)T approx. I)centerreverse arrowdot)G. All of these results are discussed within the context of models for sequence dependent DNA secondary structure, replication fidelity and mechanisms of mismatch repair, and implications for probe design. The duplex deoxyoligonucleotide d(GGATGGGAG))centerreverse arrowdot)d(CTCCCATCC) is a portion of the gene recognition sequence of the protein transcription …
Date:
December 1, 1987
Creator:
Aboul-ela, F. M.
Object Type:
Report
System:
The UNT Digital Library
Transport and Reaction Kinetics at the Glass:Solution Interface Region: Results of Repository-Oriented Leaching Experiments
Repository-oriented leaching experiments involving Savannah River Laboratory (SRL) 165 type glass under a {gamma}-radiation field (1 = 0.2 x 10{sup 4} R/h) have been performed by the Nevada Nuclear Waste Storage Investigations (NNWSI) project. In this communication, we discuss glass surface analyses obtained by SEM, nuclear resonance profiling, and SIMS together with leachate solution data in relation to a mechanism that couples diffusion, hydrolysis (etching and gelation), and precipitation to qualitatively describe the release of different glass components to the leachant solutions. The release of mobile (e.g., Li) and partly mobile (e.g., B) species is controlled primarily by interdiffusion with water species across the interdiffusion zone. Glass components that are immobile in the interdiffusion zone are released to the solution by etching. For prediction of long-term steady-state concentrations of glass components with low solubility, the relative rates of release from the glass and secondary mineral precipitation must be taken into account.
Date:
December 31, 1986
Creator:
Abrajano, T. A., Jr. & Bates, J. K.
Object Type:
Report
System:
The UNT Digital Library
The development of a selective ruthenium catalyst. Technical progress report, January 1, 1988--March 31, 1988
A new ruthenium modifier has been identified which improves the catalyst`s stability. The modified catalyst with 2.8% Ru achieved 80% conversion at 150 gas hourly space velocity and is expected to have at least 1 year catalyst life with no more tan 6.6% C{sub 1}{minus}C{sub 4} selectivity. Activity increase is identified to be the future catalyst developmental need. Work during the next quarter will focus on writing the final report for the program.
Date:
December 31, 1988
Creator:
Abrevaya, H.
Object Type:
Report
System:
The UNT Digital Library